BACKGROUND OF THE INVENTION
1. Field of the Invention
[0001] The present invention relates generally to the field of fine powder processing, and
particularly to the metered transport of fine powders. More particularly, the present
invention relates to systems, apparatus and methods for filling receptacles with unit
dosages of non-flowable but dispersible fine powdered medicaments, particularly for
subsequent inhalation by a patient
[0002] Effective delivery to a patient is a critical aspect of any successful drug therapy.
Various routes of delivery exist, and each has its own advantages and disadvantages.
Oral drug delivery of tablets, capsules, elixirs, and the like, is perhaps the most
convenient method, but many drugs have disagreeable flavors, and the size of the tablets
makes them difficult to swallow. Moreover, such medicaments are often degraded in
the digestive tract before they can be absorbed. Such degradation is a particular
problem with modern protein drugs which are rapidly degraded by proteolytic enzymes
in the digestive tract. Subcutaneous injection is frequently an effective route for
systemic drug delivery, including the delivery of proteins, but has a low patient
acceptance and produces sharp waste items, e.g. needles, which are difficult to dispose.
Since the need to inject drugs on a frequent schedule such as insulin one or more
times a day, can be a source of poor patient compliance, a variety of alternative
routes of administration have been developed, including transdermal, intranasal, intrarectal,
intravaginal, and pulmonary delivery.
[0003] Of particular interest to the present invention are pulmonary drug delivery procedures
which rely on inhalation of a drug dispersion or aerosol by the patient so that the
active drug within the dispersion can reach the distal (alveolar) regions of the lung.
It has been found that certain drugs are readily absorbed through the alveolar region
directly into blood circulation. Pulmonary delivery is particularly promising for
the delivery of proteins and polypeptides which are difficult to deliver by other
routes of administration. Such pulmonary delivery can be effective both for systemic
delivery and for localized delivery to treat diseases of the lungs.
[0004] Pulmonary drug delivery (including both systemic and local) can itself be achieved
by different approaches, including liquid nebulizers, metered dose inhalers (MDI's)
and dry powder dispersion devices. Dry powder dispersion devices are particularly
promising for delivering protein and polypeptide drugs which may be readily formulated
as dry powders. Many otherwise labile proteins and polypeptides may be stably stored
as lyophilized or spray-dried powders by themselves or in combination with suitable
powder carriers. A further advantage is that dry powders have a much higher concentration
than medicaments in liquid form.
[0005] The ability to deliver proteins and polypeptides as dry powders, however, is problematic
in certain respects. The dosage of many protein and polypeptide drugs is often critical
so it is necessary that any dry powder delivery system be able to accurately, precisely
and repeatably deliver the intended amount of drug. Moreover, many proteins and polypeptides
are quite expensive, typically being many times more costly than conventional drugs
on a per-dose basis. Thus, the ability to efficiently deliver the dry powders to the
target region of the lung with a minimal loss of drug is critical.
[0006] For some applications, fine powder medicaments are supplied to dry powder dispersion
devices in small unit dose receptacles, often having a puncturable lid or other access
surface (commonly referred to as blister packs). For example, the dispersion devices
described in
U.S. Patent Nos. 5,785,049 and
5,740,794 are constructed to receive such a receptacle. Upon placement of the receptacle in
the device, a multi-flow ejector assembly having a feed tube is penetrated through
the lid of the receptacle to provide access to the powdered medicament therein. The
multi-flow ejector assembly also creates vent holes in the lid to allow the flow of
air through the receptacle to entrain and evacuate the medicament. Driving this process
is a high velocity air stream which is flowed past a portion of the tube, such as
an outlet end, to draw powder from the receptacle, through the tube, and into the
flowing air stream to form an aerosol for inhalation by the patient. The high velocity
air stream transports the powder from the receptacle in a partially de-agglomerated
form, and the final complete de-agglomeration takes place in the mixing volume just
downstream of the high velocity air inlets.
[0007] Of particular interest to the present invention are the physical characteristics
of poorly flowing powders. Poorly flowing powders are those powders having physical
characteristics, such as flowability, which are dominated by cohesive forces between
the individual units or particles (hereinafter "individual particles") which constitute
the powder. In such cases, the powder does not flow well because the individual particles
cannot easily move independently with respect to each other, but instead move as clumps
of many particles. When such powders are subjected to low forces, the powders will
tend not to flow at all. However, as the forces acting upon the powder are increased
to exceed the forces of cohesion, the powder will move in large agglomerated "chunks"
of the individual particles. When the powder comes to rest, the large agglomerations
remain, resulting in a non-uniform powder density due to voids and low density areas
between the large agglomerations and areas of local compression.
[0008] This type of behavior tends to increase as the size of the individual particles becomes
smaller. This is most likely because, as the particles become smaller, the cohesive
forces, such as Van Der Waals, electrostatic, friction, and other forces, become large
with respect to the gravitational and inertial forces which may be applied to the
individual particles due to their small mass. This is relevant to the present invention
since gravity and inertial forces produced by acceleration, as well as other effected
motivators, are commonly used to process, move and meter powders.
[0009] For example, when metering the fine powders prior to placement in the unit dose receptacle,
the powders often agglomerates inconsistently, creating voids and excessive density
variation, thereby reducing the accuracy of the volumetric metering processes which
are commonly used to meter in high throughput production. Such inconsistent agglomeration
is further undesirable in that the powder agglomerates need to be broken down to the
individual particles, i.e. made to be dispersible, for pulmonary delivery. Such de-agglomeration
often occurs in dispersion devices by shear forces created by the air stream used
to extract the medicament from the unit dose receptacle or other containment, or by
other mechanical energy transfer mechanisms (e.g., ultrasonic, fan/impeller, and the
like). However, if the small powder agglomerates are too compacted, the shear forces
provided by the air stream or other dispersing mechanisms will be insufficient to
effectively disperse the medicament to the individual particles.
[0010] Some attempts to prevent agglomeration of the individual particles are to create
blends of multi-phase powders (typically a carrier or diluent) where larger particles
(sometimes of multiple size ranges), e.g. approximately 50 µm, are combined with smaller
drug particles, e.g. 1 µm to 5 µm. In this case, the smaller particles attach to the
larger particles so that under processing and filling the powder will have the characteristics
of a 50 µm powder. Such a powder is able to more easily flow and meter. One disadvantage
of such a powder, however, is that removal of the smaller particles from the larger
particles is difficult, and the resulting powder formulation is made up largely of
the bulky flowing agent component which can end up in the device, or the patient's
throat.
[0011] Current methods for filling unit dose receptacles with powdered medicaments include
a direct pouring method where a granular powder is directly poured via gravity (sometimes
in combination with stirring or "bulk" agitation) into a metering chamber. When the
chamber is filled to the desired level, the medicament is then expelled from the chamber
and into the receptacle. In such a direct pouring process, variations in density can
occur in the metering chamber, thereby reducing the effectiveness of the metering
chamber in accurately measuring a unit dose amount of the medicament. Moreover, the
powder is in a granular state which can be undesirable for many applications.
[0012] Some attempts have been made to minimize density variations by compacting the powder
within, or prior to depositing it in the metering chamber. However, such compaction
is undesirable, especially for powders made up of only fine particles, in that it
decreases the dispersibility of the powder, i.e. reduces the chance for the compacted
powder to be broken down to the individual particles during pulmonary delivery with
a dispersion device.
[0013] It would therefore be desirable to provide systems and methods for the processing
of fine powders which would overcome or greatly reduce these and other problems. Such
systems and methods should allow for accurate and precise metering of the fine powder
when divided into unit doses for placement in unit dose receptacles, particularly
for low mass fills. The systems and methods should further ensure that the fine powder
remains sufficiently dispersible during processing so that the fine powder may be
used with existing inhalation devices which require the powder to be broken down to
the individual particles before pulmonary delivery. Further, the systems and methods
should provide for the rapid processing of the fine powders so that large numbers
of unit dose receptacles can rapidly be filled with unit dosages of fine powder medicaments
in order to reduce cost.
2. Description of the Background Art
[0014] U.S. Patent No. 5,765,607 describes a machine to meter products into containers and includes a metering unit
to supply the product into containers.
[0015] U.S. Patent No. 4,640,322 describes a machine which applies sub-atmospheric pressure through a filter to pull
material directly from a hopper and laterally into a non-rotatable chamber.
[0016] U.S. Patent 4,509,568 describes a granular material processing apparatus employing a rotating paddle to
stir the granular material.
[0017] U.S. Patent No. 2,540,059 describes a powder filling apparatus having a rotating wire loop stirrer for stirring
powder in a hopper before directly pouring the powder into a metering chamber by gravity.
[0019] Product brochure, "E-1300 Powder Filler" describes a powder filler available from
Perry Industries, Corona, CA.
[0020] U.S. Patent No. 3,874,431 describes a machine for filling capsules with powder. The machine employs coring
tubes that are held on a rotatable turret.
[0021] British Patent No. 1,420,364 describes a membrane assembly for use in a metering cavity employed to measure quantities
of dry powders.
[0022] British Patent No. 1,309,424 describes a powder filling apparatus having a measuring chamber with a piston head
used to create a negative pressure in the chamber.
[0023] Canadian Patent No. 949,786 describes a powder filling machine having measuring chambers that are dipped into
the powder. A vacuum is then employed to fill the chamber with powder.
[0024] US Patent No. 5,377,727 describes an apparatus for measuring out and delivering particulate or granular material,
employing a container conveyor, a feed roller with axially-spaced measuring pockets,
a hopper disposed above the feed roller and a filling chute disposed between the conveyor
and the feed roller. A blocking preventing agitating bar is provided inside the hopper.
SUMMARY OF THE INVENTION
[0025] According to a first aspect of the present invention, there is provided a method
for transporting a fine powder as claimed in claim 1.
[0026] According to a second aspect of the present invention, there is provided an apparatus
for transporting a fine powder as claimed in claim 19.
[0027] The invention provides systems, apparatus and methods for the metered transport of
fine powders into unit dose receptacles. In one exemplary method, such fine powders
are transported by first agitating the fine powders with a vibrating element, and
then capturing at least a portion of the fine powder. The captured fine powder is
then transferred to a receptacle, with the transferred powder being sufficiently uncompacted
so that it can be substantially dispersed upon removal from the receptacle. Usually,
the fine powder will comprise a medicament with the individual particles having a
mean size that is less than about 100 µm, usually less than about 10 µm, and more
usually in the range from about 1 µm to 5 µm.
[0028] The fine powder will preferably be placed into a hopper having an opening at a bottom
end. The element is vibrated to agitate the fine powder. Vibration of the powder in
the vicinity of the opening assists in the transfer of a portion of the fine powder
through the opening where it may be captured into a chamber. Vibration of the element
also assists in de-agglomerating powder within the metering chamber so that the metering
chamber may more uniformly be filled.
[0029] The vibratable element is vibrated in an up and down, i.e. vertical, motion relative
to the powder in the hopper. In one aspect, an ultrasonic horn is employed to vertically
vibrate the element. In one aspect, the rod is operably attached to a piezoelectric
motor which vibrates the rod. The element is vertically vibrated at a frequency in
the range from about 1,000 Hz to about 180,000 Hz, and more preferably from about
10,000 Hz to about 40,000 Hz, and most preferably from about 15,000 Hz to about 25,000
Hz.
[0030] In another aspect, the element has a distal end which is placed near the opening.
Further, the distal end has an end member which is vibrated over the chamber to assist
in transfer of the fine powder from the hopper to the chamber. The end member preferably
projects laterally outward from the element. In one aspect, the end member comprises
a cylinder when the element is vibrated vertically. In another aspect, the end member
comprises a cross-member when the rod is laterally vibrated. Preferably, the end-member
is vertically spaced apart from the chamber by a distance in the range from about
0.01 mm to about 10 mm, and more preferably from about 0.5 mm to about 3.0 mm. Such
a distance assists in keeping the powder uncompacted when transferred to the chamber.
[0031] In still another aspect, the element is preferably moved across the opening while
being vibrated. For instance, the element may be translated along the opening at a
rate that is preferably less than about 100 cm/s. However, the particular rate of
translation will typically depend on the vibrational frequency of the element. In
this way, the element is swept across the chamber while being vibrated.
[0032] Movement of the element along the opening is particularly preferable when multiple
chambers are aligned with the opening. In this way, the element may be employed to
assist in the transfer of fine powder from the hopper into each of the chambers. Optionally,
a plurality of elements or rods may be vibrated within the hopper in the vicinity
of the openings. Preferably, the rods will be aligned with each other and will be
translated along the opening while being vibrated, although in some cases the rods
or elements may remain stationary over each chamber.
[0033] To assist in the capture of the fine powder in the chamber, air is preferably drawn
through the chamber bottom to draw the fine powder into the chamber. Following capture
of the fine powder, the powder is preferably transferred to a receptacle. Transferring
of the fine powder is preferably accomplished by introducing a compressed gas into
the chamber to expel the captured powder into the receptacle.
[0034] In another aspect of the method, the powder in the hopper is periodically levelled.
As one example, the powder may be levelled by placing a projecting member above the
distal end of the vibratable element. In this way, the projecting member vibrates
along with the vibratable element. As the element is translated along the hopper,
the projecting member tends to level the powder in the hopper. In one aspect, transfer
of the powder is performed in a moisture controlled environment.
[0035] In still another aspect, the powder captured by the chamber is adjusted to be a unit
dose amount. This may be accomplished by placing a thin plate (or doctor sheet) between
the hopper and the chamber. The plate has an aperture to allow for the transfer of
the powder from the hopper and into the chamber. The chamber is then moved relative
to the plate, with the plate scraping any excess powder from the chamber. Alternatively,
a doctor blade may be employed to scrape any excess powder from the chamber as the
chamber is rotated.
[0036] In one particular aspect, the powder is transferred to the hopper from a secondary
hopper. Preferably, the secondary hopper is vibrated to transfer the powder onto a
chute where it passes into the primary hopper. In still yet another aspect, the chamber
is periodically removed and replaced with a chamber of a different size to adjust
the volume of the chamber. In this way, different unit dosages may be produced by
the invention.
[0037] The invention further provides an exemplary apparatus for transporting a fine powder.
The apparatus comprises a hopper for holding the fine powder. The apparatus further
includes at least one chamber which is moveable to allow the chamber to be placed
in close proximity to an opening in the hopper. A vibratable element is also provided
having a proximal end and a distal end, with the element being placed within the hopper
such that the distal end is near the opening. A vibrator is provided to vibrate the
element when within the fine powder. In this way, the element may be vibrated to agitate
the fine powder to assist in its transfer from the hopper to the chamber. Preferably,
the vibrator comprises an ultrasonic horn which vibrates the element in an up and
down or vertical motion.
[0038] In one exemplary aspect, the apparatus further includes a mechanism for translating
the vibratable element or rod over the chamber as the element is vibrated. Such a
mechanism is particularly advantageous when a plurality of chambers are provided in
a rotatable member which is rotated to align the chambers with the opening. The translating
mechanism may then be employed to translate the element over the rotatable member
so that the vibrating element passes over each chamber to assist in the filling of
each with powder. The translating mechanism preferably comprises a linear drive mechanism
which translates the rod along the opening at a rate that is less than about 100 cm/s.
[0039] The vibrator is configured to vibrate the element in an up and down motion at a frequency
in the range from about 1,000 Hz to about 180,000 Hz, and more preferably in the range
from about 10,000 Hz to about 40,000 Hz, and most preferably in the range from about
15,000 Hz to about 25,000 Hz. When vibrated up and down, the vibratable element preferably
comprises a cylindrical shaft having a diameter in the range from about 1.0 mm to
about 10 mm.
[0040] An end-member is preferably operably attached to the distal end of the vibratable
element to assist in agitation of the fine powder. The end-member is preferably vertically
spaced apart from the chamber by a distance in the range from about 0.01 mm to about
10 mm, and more preferably from about 0.5 mm to about 3.0 mm. In one alternative,
the apparatus is provided with a plurality of vibratable elements so that multiple
elements may be vibrated within the fine powder.
[0041] In still another aspect, the chamber is disposed within a rotatable member which
is placed in a first position having the chamber aligned with the opening in the hopper,
and a second position having the chamber aligned with a receptacle. In this way, the
chamber may be filled with powder when in the first position. The rotatable member
is then rotated to the second position to allow the powder to be expelled from the
chamber and into the receptacle. The chamber preferably includes a port which is in
communication with a vacuum source to assist in drawing the fine powder from the hopper
and into the chamber. A filter is preferably disposed across the port to assist in
capturing the powder. A source of compressed gas is preferably also in communication
with the port to eject the captured powder from the chamber and into the receptacle.
A controller may be provided for controlling actuation of the gas source, the vacuum
source and operation of the vibrator.
[0042] The apparatus may also include a mechanism for adjusting the amount of captured powder
in the chamber due to the chamber volume. In this way, the captured amount will be
a unit dose amount. Such an adjustment mechanism may comprise an edge for removing
fine powder extending above the chamber. In one embodiment, the adjustment mechanism
comprises a thin plate having an aperture which may be aligned with the chamber during
filling. As the rotatable member is rotated, the edge of the aperture scrapes the
excess powder from the chamber.
[0043] In one particular aspect, the vibratable element includes a projecting member which
is spaced above the distal end. The projecting member serves as a leveller to level
powder within the hopper as the vibratable element is translated along the hopper.
[0044] In another aspect, a secondary hopper is provided to store the powder until delivered
to the primary hopper. A shaking mechanism is provided to vibrate the secondary hopper
when powder is to be transferred to the primary hopper. Preferably, the powder passes
down a chute so that the powder may be transferred without interfering with the translation
of the vibratable member along the primary hopper.
[0045] In still another aspect, the chamber is formed in a change tool. In this way, the
size of the chamber may be varied simply by attaching a change tool with a different
sized chamber to the rotatable member.
BRIEF DESCRIPTION OF THE DRAWINGS
[0046]
Fig. 1 is a cross-sectional side view of an apparatus for transporting fine powders.
This is outside the scope of the claimed invention.
Fig. 2 is an end view of the apparatus of Fig. 1. This is outside the scope of the
claimed invention.
Fig. 3 is a more detailed view of a chamber of the apparatus of Fig. 1 showing a vibrating
rod being translated over the chamber. This is outside the scope of the claimed invention.
Fig. 4 is a left front perspective view of an exemplary system for transporting powder.
This is outside the scope of the claimed invention.
Fig. 5 is a right front perspective view of the system of Fig. 4. This is outside
the scope of the claimed invention.
Fig. 6 is a cross-sectional view of the system of Fig. 4. This is outside the scope
of the claimed invention.
Fig. 7 is a schematic view of an alternative apparatus for transporting fine powders
This is outside the scope of the claimed invention.
Fig. 8 is a schematic view of still another alternative apparatus for transporting
fine powders. This is outside the scope of the claimed invention.
Fig. 9 is a schematic view of still another alternative apparatus for transporting
fine powders. This is outside the scope of the claimed invention.
Fig. 10 is a perspective view of an embodiment of an apparatus for transporting fine
powders according to the invention.
Fig. 11 is a cross-sectional, view of the apparatus of Fig. 10 taken along lines 11-11
Fig. 12 is a cross-sectional view of the apparatus of Fig. 10 taken along lines 12-12.
Fig. 13 is an exploded view of a rotatable member of the apparatus of Fig. 10.
Fig. 14A is a schematic view of a scraping mechanism for scraping excess powder from
a chamber of a rotatable member.
Fig. 14B is an end view of the scraping mechanism of Fig. 14A as mounted above the
rotatable member.
Fig. 14C is a perspective view of an alternative mechanism for scraping excess powder
from a chamber of a rotatable member according to the invention.
Fig. 15 is a perspective view of a particularly preferable system for transporting
powders according to the invention.
DETAILED DESCRIPTION OF THE SPECIFIC EMBODIMENTS
[0047] The invention provides methods and apparatus for the metered transport of fine powders
into receptacles. The fine powders are very fine, usually having a mean size in the
range that is less than about 20 µm, usually less than about 10 µm, and more usually
from about 1 µm to 5 µm, although the invention may in some cases be useful with larger
particles, e.g., up to about 50 µm or more. The fine powder may be composed of a variety
of constituents and will preferably comprise a medicament such as proteins, nucleic
acids, carbohydrates, buffer salts, peptides, other small biomolecules, and the like.
The receptacles intended to receive the fine powder preferably comprise unit dose
receptacles. The receptacles are employed to store the unit dosage of the medicament
until needed for pulmonary delivery. To extract the medicament from the receptacles,
an inhalation device, such as those described in
U.S. Patent Nos. 5,785,049 and
5,740,794 may be employed. However, the methods of the invention are also useful in preparing
powders to be used with other inhalation devices which rely on the dispersement of
the fine powder.
[0048] The receptacles are preferably each filled with a precise amount of the fine powder
to ensure that a patient will be given the correct dosage. When metering and transporting
the fine powders, the fine powders will be delicately handled and not compressed,
so that the unit dosage amount delivered to the receptacle is sufficiently dispersible
to be useful when used with existing inhalation devices. The fine powders prepared
by the invention will be especially useful with, although not limited to, "low energy"
inhalation devices which rely on manual operation or solely upon inhalation to disperse
the powder. With such inhalation devices, the powder will preferably be at least 20%
(by weight) dispersible or extractable into a flowing air stream, more preferably
be at least 60% dispersible, and most preferably at least 90% dispersible as defined
in
U.S. Patent No. 5,785,049. Since the cost of producing the fine powder medicaments are usually quite expensive,
the medicament will preferably be metered and transported into the receptacles with
minimal wastage. Preferably, the receptacles will be rapidly filled with the unit
dosage amounts so that large numbers of receptacles containing the metered medicament
can economically be produced.
[0049] According to the invention, the fine particles are captured in a metering chamber
(which is preferably sized to define a unit dosage volume). A preferable method of
capturing is by drawing air through the chamber so that the drag force of the air
will act upon the small agglomerates or individual particles as described in
U.S. Patent No. 5,775,320. In this way, the fluidized fine powder fills the chamber without substantial compaction
and without substantial formation of voids. Further, capturing in this manner allows
the fine powder to be accurately and repeatably metered without unduly decreasing
the dispersibility of the fine powder. The flow of air through the chamber may be
varied in order to control the density of the captured powder.
[0050] After the fine powder is metered, the fine powder is ejected into the receptacle
in a unit dosage amount, with the ejected fine powder being sufficiently dispersible
so that it may be entrained and aerosolized in the turbulent air flow created by an
inhalation or dispersion device. Such an ejection process is described in
U.S. Patent No. 5,775,320.
[0051] Agitation of the fine powders is preferably accomplished by vibrating a vibratable
member within the fine powder in the vicinity just above the capture chamber. The
element is vibrated in an up and down, i.e., vertical, motion. A variety of mechanisms
may be employed to vibrate the elements including an ultrasonic horn.
[0052] Referring to Figs. 1 and 2, a specific apparatus 10 for metering and transporting
unit dosages of a fine powder medicament will be described. This is outside the scope
of the claimed invention. Apparatus 10 comprises a trough or hopper 12 having a top
end 14 and a bottom end 16. At bottom end 16 is an opening 18. Held within hopper
12 is a bed of fine powder 20. Positioned below hopper 12 is a rotatable member 22
having a plurality of chambers 24 about its periphery. Rotatable member 22 may be
rotated to align chambers 24 with opening 18 to allow powder 20 to be transferred
from hopper 12 and into chambers 24.
[0053] Positioned above hopper 12 is piezoelectric bending motor 26 having a rod 28 attached
thereto. Piezoelectric motor 26 is positioned above hopper 12 such that a distal end
29 of rod 28 is placed within the fine powder bed 20 while being spaced apart from
rotatable member 22. Bottom end 16 of hopper 12 is positioned just above rotatable
member 22 so that powder held within hopper 12 will not escape between bottom end
16 and rotatable member 22. At distal end 29 of rod 28 is a cross-member 30 which
is generally perpendicular to rod 28. Cross-member 30 will preferably be at least
as long as the top diameters of chambers 24 to assist in agitating fine powder into
the chambers as described in greater detail hereinafter.
[0054] As best illustrated in Fig. 1, upon actuation of. piezoelectric bending motor 26,
rod 28 is caused to vibrate back and forth as indicated by arrows 32. Further, as
illustrated by arrow 34, piezoelectric bending motor 26 is translatable along the
length of rotatable member 22 to allow cross-member 30 to be vibrated over each of
the chambers 24.
[0055] Referring now to Fig. 3, the transfer of powder from hopper 12 (see Fig. 1) to chamber
24 will be described in greater detail. Disposed within chamber 24 is a top filter
36 and a back-up filter 38. Top filter 36 is disposed in rotatable member 22 such
that it is at a known distance relative to the top of chamber 24. A line 40 is in
communication with chamber 24 to provide suction within chamber 24 during filling
and compressed gas when expelling the powder from chamber 24 in a manner similar to
that described in copending
U.S. Patent Application Serial No. 08/638,515.
[0056] When ready for filling, a vacuum is created within line 40 to draw air through chamber
24. Further, rod 28 is vibrated as shown by arrows 32 when positioned above chamber
24 to assist in agitating powder bed 20. Such a process assists in transferring the
powder from bed 20 and into chamber 24. While vibrating, rod 28 is translated over
chamber 24 as indicated by arrow 34. In this way, agitation of the powder bed 20 will
occur over substantially the entire opening of the chamber 24. Further, translation
of rod 28 will also move rod 28 over other chambers so that they may be filled in
a similar manner.
[0057] As illustrated by arrows 42, rod 28 will preferably be vertically spaced from rotatable
member 22 by a distance in the range from about 0.01 mm to about 10 mm, and more preferably
from about 0.1 mm to about 0.5 mm. Such vertical spacing is preferred to ensure that
the powder immediately above the cavity is fluidized and can be drawn into the chamber
24. Referring now to Figs. 4-6, a specific powder transferring and metering system
44 will be described. This is outside the scope of the claimed invention. System 44
is patterned after the principles previously set forth in connection with apparatus
10 of Figs. 1-3. System 44 comprises a base 46 and a frame 48 for rotatably holding
a rotatable member 50. Rotatable member 50 includes a plurality of chambers 52 (see
Fig. 6). Rotatable member 50, including chambers 52, will preferably be provided with
vacuum and compression lines similar to that previously described in copending
U.S. Patent Application Serial No. 08/638,515. In brief, a vacuum is created to assist in drawing powder into chambers 52. Upon
filling of chambers 52, rotatable member 50 is rotated until chambers 52 are facing
downward. At that point, compressed gas is forced through chambers 52 to eject the
captured powder into receptacles, such as blister packages as are commonly used in
the art.
[0058] Positioned above rotatable member 50 is a hopper 54 having an elongate opening 56
(see Fig. 6). Operably mounted to frame 48 are a plurality of piezoelectric bending
motors 58. Attached to each of piezoelectric bending motors 58 is a rod 60. An exemplary
piezoelectric bending motor is commercially available from Piezo Systems, Inc., Cambridge,
Massachusetts. Such bending motors comprise two layers of a piezoceramic, each having
an outer electrode. An electric field is applied across the two outer electrodes to
cause one layer to expand while the other contracts.
[0059] Rod 60 will preferably comprise a stainless steel wire rod having a diameter in the
range from about 0.02 mm (0.005 inch) to about 0.40 mm (0.10 inch), and more preferably
from about 0.08 mn (0.02 inch) to about 0.16 mm (0.04 inch).
[0060] However, it will be appreciated that other materials and geometries may be used when
constructing rod 60. For example, a variety of rigid materials may be employed, including
other metals and alloys, a steel music wire, a carbon fiber, plastics, and the like.
The shape of rod 60 may also be non-circular and/or non-uniform in cross section,
with an important feature being the ability to agitate the powder near the distal
end of the rod to fluidize the powder. A perpendicular cross-member 62 (see Fig. 6)
will preferably be attached to the distal end of rod 60. One or more cross-members
may optionally be positioned above the distal cross-member to help collapse any trenches
created in the powder bed during operation. When actuated, rods 60 will preferably
be vibrated at a frequency in the range from about 5 Hz to about 50,000 Hz, and more
preferably in the range from about 50 Hz to about 5,000 Hz, and most preferably in
the range from about 50 Hz to about 1,000 Hz.
[0061] Piezoelectric bending motors 58 are attached to translation mechanism 64 which translates
rods 60 along hopper 54. When translated, cross-member 62 will preferably be vertically
spaced above chambers 52 by a distance in the range from about 0.01 mm to about 10
mm, and more preferably from about 0.1 mm to about 0.5 mm. Translation mechanism 64
comprises a rotary drive pulley 66 which rotates a belt 68, which in turn is attached
to a platform 70. Piezoelectric bending motors 58 are attached to platform 70 which
is translated over a shaft 72 when pulley 66 is actuated. In this way, rods 60 may
be translated back and forth within hopper 54 so that rods 60 will be vibrated over
each of the chambers 52. Translation mechanism 64 may be employed to pass rod 60 over
chambers 52 as many times as desired when filling chambers 52. Preferably, rod 60
will be translated at a speed that is less than about 200cm/s, and more preferably
less than about 100 cm/s. Rod 60 will preferably pass over each chamber at least one
time, with two passes being preferred.
[0062] In operation, hopper 54 is filled with fine powder that is to be transferred into
chambers 52. A vacuum is then drawn through each of chambers 52 while they are aligned
with opening 56. At the same time, piezoelectric bending motors 58 are actuated to
vibrate rods 60. Translation mechanism 64 is actuated to translate rods 60 back and
forth within hopper 54 while rods 60 are vibrating. Vibration of rods 60 agitates
the fine powder to assist in its transfer into chambers 52. When chambers 52 are sufficiently
filled, rotatable member 50 is rotated 180° to place chambers 52 in a downward position.
As rotatable member 50 is rotated, a blade at the bottom edge of hopper 54 scrapes
off any excess powder to ensure that each chamber contains only a unit dose amount
of fine powder.
[0063] When in the downward position, a compressed gas is forced through each of chambers
52 to eject the fine powder into receptacles (not shown). In this way, a convenient
method is provided for transferring fine powder from a hopper into receptacles in
a metered amount.
[0064] Referring now to Fig. 7, an alternative apparatus 74 for transferring metered doses
of fine powder will be described. This is outside the scope of the claimed invention.
Apparatus 74 comprises a housing 76 and a piezo substrate 78 operably attached to
housing 76. piezo substrate 78 includes a plurality of holes 80 (or a screen). Positioned
above substrate 78 is a hopper 82 having a bed of fine powder 84. Attached to substrate
78 is a pair of electrical leads 86 for actuation of piezo substrate 78. When electrical
current is alternately supplied to leads 86, substrate 78 is caused to expand and
contract to produce a vibration mode as illustrated by arrow 88. In turn, holes 80
are caused to vibrate to assist in agitating powder bed 84 to more effectively allow
the powder to fall through holes 80 and into a chamber. A rotatable member having
chambers in communication with a vacuum source and a pressure source as described
in previous embodiments may also be used in connection with apparatus 74 to assist
in capturing the fine powder and expelling the captured powder into receptacles.
[0065] A further apparatus 100 for transferring metered doses of fine powder is illustrated
in Fig. 8. This is outside the scope of the claimed invention. Apparatus 100 operates
similar to apparatus 10 as previously described, except that the piezoelectric bending
motor has been replaced with a motor 102 having a crank 104 which drives a linkage
shaft 106. As shaft 106 is reciprocated, a rod 108 is vibrated within a hopper 110
that is filled with powder 112. The agitated powder is then captured in a chamber
114 in a manner similar to that previously described. Further, rod 108 may be translated
over chamber 114 during vibration in a manner similar to that previously described
with other embodiments.
[0066] Another apparatus 120 for transferring metered doses of fine powder is illustrated
in Fig. 9. This is outside the scope of the claimed invention. Apparatus 120 comprises
a motor 122 which rotates a wire loop 124. As shown, wire loop 124 is disposed within
a bed of fine powder 126 just above a chamber 128. In this way, when wire loop 124
is rotated, the powder will be fluidized and drawn into chamber 128 in a manner similar
to previous apparatus. Further, loop 124 may be translated over chamber 128 during
its rotation in a manner similar to that previously described with other apparatus.
[0067] Referring now to Fig. 10, an embodiment of an apparatus 200 for transporting fine
powders will be described. Apparatus 200 operates in a manner similar to the others
as previously described in that powder is transferred from a hopper into metering
chambers of a rotatable member. From the rotatable member, the powder is expelled
into receptacles in unit dosage amounts.
[0068] Apparatus 200 comprises a frame 202 which holds a rotatable member 204 such that
rotatable member 204 may be rotated by a motor (not shown) held on frame 202. Frame
202 also holds a trough or primary hopper 206 above rotatable member 204. Positioned
above hopper 206 is a vibrator 208. As shown in Figs. 11 and 12, a vibratable element
210 is coupled to vibrator 208. Vibrator 208 is coupled to an arm 212 by a clamp 214.
Arm 212 in turn is coupled to a translation stage 216. A screw motor 217 is employed
to translate stage 216 back and forth relative to frame 202. In this way, vibratable
element 210 may be translated back and forth within hopper 206.
[0069] Referring also now to Figs. 11 and 12, apparatus 200 further includes a secondary
hopper 218 disposed above primary hopper 206. Conveniently, hopper 218 includes wings
219 to allow it to be removably coupled to frame 202 by inserting wings 219 into slots
220. Hopper 218 comprises a housing 222 and a tubular section 224 for storing powder.
A chute 226 extends from housing 222 and into hopper 206 when hopper 218 is attached
to frame 202. Tubular section 224 includes an opening 228 to allow powder to flow
from tubular section 224 and down chute 226. A screen 230 is disposed over opening
228 to generally prevent the flow of powder down chute 226 until housing 222 is shaken
or vibrated.
[0070] Conveniently, a latch 232 is employed to secure secondary hopper 218 to frame 202.
To remove secondary hopper 218, latch 232 is disengaged from hopper 218 and hopper
218 is lifted from slots 220. In this way, hopper 218 may be conveniently removed
for refilling, cleaning, replacement, or the like.
[0071] To transfer powder from hopper 218, an arm 234 is placed into contact with housing
222 and is shaken or vibrated to vibrate housing 222. A motor (not shown) is employed
to shake or vibrate arm 234. As shown in Fig. 12, housing 222 may optionally include
an internal opening 236 containing a block 238. As housing 222 is shaken, block 238
vibrates within opening 236. As block 238 engages the walls of housing 222, it sends
shock waves through housing 222 to assist in transferring the powder from tubular
section 224, through opening 228, and through screen 230. The powder then slides down
chute 226 until it falls within hopper 206. Use of chute 226 is also advantageous
in that it allows tubular section 224 to be laterally offset from vibrator 208 so
that it will not interfere with the motion of vibrator 208. One particular advantage
of including block 238 within opening 236 is that any particulate generated as block
238 is vibrated will be maintained within opening 236 and will not contaminate any
of the powder.
[0072] Vibrator 208 is configured to vibrate element 210 in an up and down or vertical motion.
Vibrator 208 preferably comprises any one of a variety of commercially available ultrasonic
horns, such as a Branson TWI ultrasonic horn. Vibratable element 210 is vibrated at
a frequency and range from about 1,000 Hz to about 180,000 Hz, and preferably from
about 10,000 Hz to about 40,000 Hz, and most preferably from about 15,000 Hz to about
25,000 Hz.
[0073] As best shown in Fig. 12, vibratable element 210 includes an end member 240 which
is appropriately shaped to optimize agitation of the fine powder during vibration
of element 210. As shown, end member 240 has an outer periphery which is greater than
that of element 210. Element 210 is preferably cylindrical in geometry and preferably
has a diameter in the range from about 0.5 mm to about 10 mm. As shown, end member
240 is also cylindrical in geometry and preferably has a diameter in the range from
about 1.0 mm to about 10 mm. However, it will be appreciated that vibratable element
210 and end member 240 may be constructed to have a variety of shapes and sizes. For
example, vibratable element 210 may be tapered. End member 240 may also have a reduced
profile to minimize the lateral movement of powder as vibrator 208 is translated through
hopper 206. Preferably, end member 240 is vertically spaced above rotatable member
204 by a distance in the range from about 0.01 mm to about 10 mm, and more preferably
from about 0.5 mm to about 3.0 mm.
[0074] Vibrator 208 is employed to assist in the transfer of powder into metering chambers
242 of rotatable member 204 in a manner similar to that described with previous embodiments.
More specifically, motor 217 is employed to translate stage 216 so that vibratable
element 210 may be translated laterally back and forth along hopper 206. At the same
time, vibratable element 210 is vibrated in an up and down motion, i.e., radial to
rotatable member 204, as it passes over each of metering chambers 242. Preferably,
vibrator 208 is laterally translated along hopper 206 at a rate that is less than
about 500 cm per second, and more preferably less than about 100 cm per second.
[0075] As vibratable element'210 is moved laterally within hopper 206, there may be a tendency
for vibratable element 210 to push or plow some of the powder towards the ends of
hopper 206. Such movement of the powder is mitigated by providing a radiating surface
or projecting member 244 on vibratable element 210 just above an average powder depth
within the hopper. In this way, accumulated powder that is higher than the average
depth is preferentially mobilized and moved to areas in the hopper having a smaller
powder depth.
Preferably, projecting member 244 is spaced apart from end member 240 by a distance
in the range from about 2 mm to about 25 mm, and more preferably from about 5 mm to
about 10 mm. As an alternative, various plowing mechanisms, such as rakes, may be
attached to vibrator 208 (or be separately articulatable) so that they will drag over
the top of the powder to assist in leveling the powder as vibrator 208 is translated
along the hopper. As another alternative, an elongate vibratory element, such as a
screen, may be disposed within the powder bed to assist in levelling the powder.
[0076] As shown in Figs. 11 and 12, rotatable member 204 is in a filling position where
metering chambers 242 are aligned with hopper 206. As with the other embodiments described
herein, once metering chambers 242 are filled, rotatable member 204 is rotated 180°
where the powder is ejected from metering chambers 242 into receptacles. A Klöckner
packaging machine is preferably employed to supply apparatus 200 with a sheet containing
the receptacles.
[0077] Referring now to Fig. 13, construction of rotatable member 204 will be described
in greater detail. Rotatable member 204 comprises a drum 246 having a front end 248
and a back end 250. Bearings 252 and 254 are insertable over ends 248 and 250 to allow
drum 246 to rotate when attached to frame 202. Rotatable member 204 further includes
a collar 256, a rear slip ring 258 and a front slip ring 259 which are fitted with
gas tight seals. Air inlets 260 and 261 are provided in collar 256. Air inlet 260
is in fluid communication with a pair 242a of metering chambers 242 while inlet 261
is in fluid communication with a pair 242b of metering chambers 242. In this way,
pressurized air or a vacuum may be produced in either pair of chambers 242a or 242b.
[0078] More specifically, air from inlet 260 passes through slip ring 258, through a hole
264 in a gasket 270 and into a hole 265 in a manifold 262. The air then passes through
manifold 262 and exits manifold 262 through a pair of holes 265a and 265b. Holes 265c
and 265d in bracket 270 then route the air into chambers 242a. In a similar manner,
air from inlet 261 passes through slip ring 259, through a hole 266 in gasket 270
and into a hole (not shown) in manifold 262. The air is routed through various holes
in manifold 262 and gasket 270 in a manner similar to that previously described with
inlet 260 until passing through chambers 242b. In this manner, two separate air circuits
are provided.
Alternatively, it will be appreciated that one of the air inlets could be eliminated
so that a vacuum or pressurized gas may be simultaneously provided to all of metering
chambers 242.
[0079] Also disposed above manifold 262 is a change tool 274. Metering chambers 242 are
formed in change tool 274, and filters 276 are disposed between change tool 274 and
air bracket 272 to form a bottom end of metering chambers 242. Air may be drawn into
chambers 242 by attaching a vacuum to air inlets 260 or 261. Similarly, a compressed
gas may be forced through metering chambers 242 by coupling a source of compressed
gas to air inlets 260 or 261. As with other embodiments described herein, a vacuum
is drawn through metering chambers 242 to assist in drawing the powder into metering
chambers 242. After drum 246 is rotated 180°, a compressed gas is forced through metering
chambers 242 to expel the powder from metering chambers 242.
[0080] Drum 246 includes an aperture 278 into which manifold 262, gasket 270, air bracket
272 and change tool 274 are inserted. A cam 280 is also provided and is insertable
into aperture 278. Cam 280 is rotated within aperture 278 to secure the various components
within drum 246. When loosened, it is possible to slide change tool 274 from aperture
278. In this way, change tool 274 may easily be replaced with another change tool
having different sized metering chambers. In this manner, apparatus 200 may be provided
with a wide assortment of change tools which allows a user to easily change the size
of the metering chambers simply by inserting a new change tool 274.
[0081] Apparatus 200 further includes a mechanism for doctoring any excess powder from metering
chambers 242. Such a doctoring mechanism 282 is illustrated in Figs. 14A and 14B and
is also referred to as a doctoring sheet. For convenience of illustration, doctoring
mechanism 282 has been omitted from the drawings of Figs. 10-12. In Figs. 14A and
14B, rotatable member 204 is shown in schematic view. Doctoring mechanism 282 comprises
a thin plate 284 having apertures 286 which are aligned with metering chambers 242
when rotatable member 204 is in the filling position. Apertures 286 preferably have
a diameter that is slightly larger than the diameter of metering chambers 242. In
this way, apertures 286 will not interfere with the filling of metering chambers 242.
Plate 284 is preferably constructed of brass and has a diameter of approximately 0.01
mm (0.003 inches). Plate 284 is sprung against rotatable member 204 so that it is
generally flush against the outer periphery. In this way, plate 284 is generally sealed
against rotatable member 204 to prevent excess powder from escaping between plate
284 and rotatable member 204. Plate 284 is attached to frame 202 and remains stationary
while rotatable member 204 rotates. In this way, after powder has been transferred
to metering chambers 242, rotatable member 204 is rotated toward the dispensing position.
During rotation, the edges of apertures 286 scrape any excess powder from metering
chambers 242 so that only a unit dose amount remains in metering chambers 242. Configuration
of doctoring mechanism 282 is advantageous in that it reduces the amount of movable
parts, thereby reducing the build up of static electricity. Further, the removed powder
remains within hopper 206 where it will be available for transfer into metering chambers
242 after they have been emptied.
[0082] Illustrated in Fig. 14C is an alternative mechanism for scraping or doctoring excess
powder from metering chambers 242. The mechanism comprises a pair of doctoring blades
290 and 292 which are coupled to hopper 206, it being appreciated that only one blade
may be needed depending on the direction of rotation of rotatable member 204. Blades
290 and 292 are preferably constructed of a thin sheet material, such as 0.02 mn (0.005
inch) brass, and are sprung lightly against rotatable member 204. The edges of blades
290 and 292 coincide approximately with the edges of the opening in hopper 206. After
metering chambers 242 are filled, rotatable member 204 is rotated, with blades 290
or 292 (depending on the direction of rotation) scraping any excess powder from metering
chambers 242.
[0083] Referring back now to Figs. 10-12, operation of apparatus 200 to fill receptacles
with unit dosages of fine powder will be described. Initially, the fine powder is
placed into tubular section 224 of secondary hopper 218. Conveniently, hopper 218
may be removed from frame 202 during filling. Housing 222 is then shaken or vibrated
for a time sufficient to transfer a desired amount of powder through opening 228,
through screen 230 and down chute 226 where it falls into primary hopper 206. Rotatable
member 204 is placed in the filling position where metering chambers 242 are aligned
with hopper 206. A vacuum is then applied to air inlets 260 and 261 (see Fig. 13)
to draw air through metering chambers 242. Under the influence of gravity, and with
the assistance of the vacuum, the powder tumbles into the metering chambers 242 and
generally fills metering chambers 242. Vibrator 208 is then actuated to vibrate element
210. At the same time, motor 217 is operated to translate vibratable element 210 back
and forth within chamber 206. As element 210 is vibrated, end member 240 creates a
pattern of air flow at the bottom of hopper 206 to agitate the powder. As end member
240 passes over each metering chamber 242, an aerosol cloud is produced that is drawn
into the metering chamber 242 by vacuum and by gravity. As end member 242 passes over
metering chambers 242, ultrasonic energy radiates down into metering chambers 242
to agitate the powder already inside the metering chamber. This in turn allows flow
within the cavity to even out any irregularities in density that may exist during
previous filling. Such a feature is particularly advantageous in that agglomerates
or chunks of powder which may create voids in the metering chamber may be broken down
to more evenly fill the metering chamber.
[0084] After passing one or more times over each of the metering chambers 242, rotatable
member 204 is rotated 180° to a dispensing position where metering chambers 242 are
aligned with receptacles (not shown). As rotatable member 204 rotates, any excess
powder is scraped from metering chambers 242 as previously described. When in the
dispensing position, a compressed gas is supplied through air inlets 260 and 261 to
expel unit dosages of powder from metering chambers 242 and into the receptacles.
[0085] The invention also provides a way to adjust fill weights by modulating the ultrasonic
power supplied to vibrator 210 as it passes over metering chambers 242. In this way,
fill weights for the various metering chambers may be adjusted to compensate for powder
weight discrepancies that may periodically occur. As one example, if the fourth metering
chamber was consistently producing a dosage amount that was too low in weight, the
power to vibrator 208 could be increased slightly each time it passed over the fourth
metering chamber. In conjunction with an automated (or manual) weighing system and
a controller, such an arrangement may be used to make an automated (or manual) closed-loop
weight control system to adjust the power level of the vibrator for each of the metering
chambers to provide more accurate fill weights.
[0086] Referring now to Fig. 15, an exemplary embodiment of a system 300 for metering and
transporting a fine powder will be described. System 300 operates in a manner similar
to apparatus 200 but includes multiple vibrators and multiple hoppers for simultaneously
filling a plurality of receptacles with unit dosages of fine powder. System 300 comprises
a frame 302 to which are rotatably coupled a plurality of rotatable members 304. Rotatable
members 304 may be constructed similar to rotatable member 204 and include a plurality
of metering chambers (not shown) for receiving powder. The number of rotatable members
and metering chambers may be varied according to the particular application.
Disposed above each rotatable member 304 is a primary hopper 306 which holds the powder
above rotatable members 304. A vibrator 308 is disposed above each hopper 306 and
includes a vibratable element 310 to agitate the powder within hopper 306 in a manner
similar to that described in connection with apparatus 200. Although not shown for
convenience of illustration, a secondary hopper which is similar to secondary hopper
218 of apparatus 200 will be disposed above each of primary hoppers 306 to transfer
powder into hoppers 306 in a manner similar to that described in connection with apparatus
200.
[0087] A motor 312 (only one being shown for convenience of illustration) is coupled to
each of rotatable members 304 to rotate rotatable members 304 between a filling position
and a dispensing position similar to apparatus 200.
[0088] Each vibrator 308 is coupled to an arm 314 by a clamp 316. Arms 314 are in turn coupled
to a common stage 318 which having slides 319 which are translatable over tracks 321
by a screw 320 of a screw motor 322. In this way, the vibratable elements 310 may
simultaneously be moved back and forth in hoppers 306 by operation of screw motor
322. Alternatively, each of vibrators could be coupled to a separate motor so that
each vibrator may independently be translated.
[0089] Frame 302 is coupled to a base 324 which includes a plurality of elongate grooves
326. Grooves 326 are adapted to receive bottom ends of a plurality of receptacles
328 which are formed in a sheet 330. Sheet 330 is preferably supplied from a blister
maker, such as a commercially available Uhlmann Packaging Machine, Model No. 1040.
Rotatable members 304 preferably include a number of metering chambers that correspond
to the number of receptacles in each row of sheets 330. In this way, four rows of
receptacles may be filled during each cycle of operation. Once four of the rows are
filled, the metering chambers are again refilled and sheet 330 is advanced to align
four new rows of receptacles with hoppers 306.
[0090] One particular advantage of system 300 is that it may be fully automated. For example,
a controller may be coupled to the packaging machine, vacuum and pressurized gas sources,
motors 312, motor 322 and vibrators 308. By use of such a controller, sheet 330 may
automatically be advanced to the proper position whereupon motors 312 are actuated
to align the metering chambers with hoppers 306. A vacuum source is then actuated
to draw a vacuum through the metering chambers while vibrators 308 are actuated and
motor 322 is employed to translate vibrators 308. Once the metering chambers are filled,
the controller is employed to actuate motors 312 to rotate rotatable members 304 until
they are aligned with receptacles 328. The controller then sends a signal to send
a pressurized gas through the metering chambers to expel the metered powder into receptacles
328. Once filled, the controller causes the packaging machine to advance the sheet
330 and to repeat the cycle. When needed, the controller may be employed to actuate
motors (not shown) to vibrate the secondary hoppers to transfer powder into primary
hoppers 306 as previously described.
[0091] Although shown with vibrators which comprise ultrasonic horns, it will be appreciated
that other types of vibrators and vibratable elements may be employed, including those
previously described herein. Further, it will be appreciated that the number of vibrators
and size of the troughs may be varied according to the particular need.
[0092] Although the foregoing invention has been described in some detail by way of illustration
and example, for purposes of clarity of understanding, it will be obvious that certain
changes and modifications may be practiced within the scope of the appended claims.
1. A method for transporting a fine powder (20) comprising:
placing the fine powder (20) into a hopper (12) having an opening (18) therein;
vibrating a vibratable element (28) within the fine powder (20) in the vicinity of
the opening (18);
vibrating the vibratable element (28) in an up and down motion relative to the powder
(20) in the hopper (12);
wherein the vibratable element (28, 210) is vibrated at a frequency in the range from
about 1,000 Hz to about 180,000 Hz; and
capturing at least a portion of the fine powder (20) exiting the opening (18) within
a chamber (24), wherein the captured powder (20) is sufficiently uncompacted so that
it may be dispersed upon removal from the chamber (24).
2. A method as in claim 1, wherein the vibratable element (28, 210) is coupled to an
ultrasonic horn, and wherein the vibrating step comprises actuating the ultrasonic
horn.
3. A method as in claim 1, wherein the vibratable element (28) has a distal end (29)
which is placed near the opening (18), and wherein the distal end (29) has an end-member
(240) attached thereto which is vibrated over the chamber (24).
4. A method as in claim 3, wherein the end-member (240) is vertically spaced apart from
the chamber (24) by a distance in the range from about 0.01 mm to about 10 mm.
5. A method as in claim 1, further comprising moving the element (28) across the opening
(18) while vibrating the element.
6. A method as in claim 5, further comprising translating the element (28, 210) along
the opening (18) at a rate that is less than about 100 cm/s.
7. A method as in claim 1, further comprising periodically levelling the powder (20)
within the hopper (12).
8. A method as in claim 7, wherein the levelling step comprises placing a projecting
member (30, 244) on the vibratable element (28, 210) at a location spaced apart from
a distal end (29) of the vibratable element (28, 210).
9. A method as in claim 1, wherein multiple chambers (24, 52) are aligned with the opening
(18, 56), and further comprising moving the vibratable element (28, 60) along the
opening (18, 56) to pass over each chamber (24, 52).
10. A method as in claim 1, wherein the fine powder (20) comprises a medicament composed
of individual particles having a means size in the range from about 1 µm to 100 µm.
11. A method as in claim 1, wherein the capturing step further comprises drawing air through
the chamber (24, 52) which is positioned below the opening (18, 56), wherein the drawn
air assists in drawing the fine powder (20) into the chamber (24, 52).
12. A method as in claim 1, further comprising transferring the captured powder (20) from
the chamber (24, 52) to a receptacle.
13. A method as in claim 12, wherein the transferring step comprises introducing a compressed
gas into the chamber (24, 52) to expel the captured powder (20) into the receptacle.
14. A method as in claim 1, further comprising adjusting the amount of captured powder
(20) to be a unit dosage amount.
15. A method as in claim 14, wherein the adjusting step comprises providing a thin plate
(284) below the hopper (12), with the plate (284) having an aperture (286) that is
aligned with the chamber (24, 242), and further comprising moving the chamber (24,
242) relative to the plate (284) to scrape the excess powder (20) from the chamber
(24, 242).
16. A method as in claim 1, wherein the hopper (12) is a primary hopper (206, 306), and
wherein the placing step comprises transferring the powder (20) from a secondary hopper
(218) to the primary hopper (206, 306).
17. A method as in claim 16, further comprising vibrating the secondary hopper (218) to
transfer the powder (20) to the primary hopper (206, 306).
18. A method as in claim 1, further comprising dispensing the powder (20) from the chamber
(242) and changing the size of the chamber (242).
19. Apparatus (200) for transporting a fine powder (20), comprising:
a hopper (12) having an opening (18) therein, the hopper (12) being adapted to receive
the fine powder (20);
at least one chamber (242) which is movable to allow the chamber (242) to be placed
in close proximity to the opening (18);
a vibratable member (210) having a proximal end and a distal end (29), the vibratable
member (210) being positionable within the hopper (12) such that the distal end (29)
is near the opening (18); and
a vibrator motor (208) to vibrate the vibratable member (210) when within the fine
powder (20),
wherein the vibrator motor (208) is adapted to vibrate the vibratable member (210)
in an up and down motion relative to the powder (20); and
wherein the vibrator motor (208) is adapted to vibrate the vibratable member (210)
at a frequency in the range from about 1,000 Hz to about 180,000 Hz.
20. An apparatus as in claim 19, further comprising a mechanism (216, 217) for translating
the vibratable member (210) over the chamber (242).
21. An apparatus (200) as in claim 20, further comprising a rotatable member (204) having
a plurality of chambers (242) about its periphery which are alignable with the opening
(18, 56), and wherein the translating mechanism (216, 217), is configured to translate
the vibratable member (210) along the opening (18, 56) so that the vibratable member
(210) passes over each chamber (242).
22. An apparatus (200) as in claim 20, wherein the translating mechanism (216, 217) comprises
a linear drive mechanism which translates the vibratable member (210) along the opening
at a rate that is less than about 100 cm/s.
23. An apparatus (200) as in claim 19, wherein the vibrator comprises an ultrasonic horn
which vibrates the element in said up and down motion relative to the powder (20).
24. An apparatus (200) as in claim 23, wherein the vibratable element is cylindrical in
geometry and has a diameter in the range from about 1.0 mm to about 10 mm.
25. An apparatus (200) as in claim 24, further comprising an end member (240) at the distal
end (29) of the vibratable member (210).
26. An apparatus (200) as in claim 25, wherein the end member (240) radially extends from
the vibratable element.
27. An apparatus (200) as in claim 25, further comprising a powder levelling member (244)
spaced about the end member (240).
28. An apparatus (200) as in claim 19, wherein the chamber (242) is disposed within a
rotatable member (304) which is placed in a first position having the chamber (242)
aligned with the opening, and a second position having the chamber (242) aligned with
a receptacle (328).
29. An apparatus (200) as in claim 19, further comprising a port in the bottom of the
chamber (242), and a vacuum source in communication with the port to assist in drawing
the fine powder (20) from the hopper (306) and into the chamber (242).
30. An apparatus (200) as in claim 29, further comprising a filter (276) disposed across
the port.
31. An apparatus (200) as in claim 29, further comprising a source of compressed gas in
communication with the port to eject the captured powder (20) from the chamber (242)
and into the receptacle (328).
32. An apparatus (200) as in claim 31, further comprising a controller for controlling
actuation of the gas source and the vacuum source.
33. An apparatus (200) as in claim 28, further comprising a plurality of hoppers disposed
above a plurality of rotatable members which each include a plurality of chambers
(242), and further comprising a plurality of elements and a plurality of vibrators
to vibrate the elements.
34. An apparatus (200) as in claim 19, further comprising a plate disposed below the hopper,
with the plate having an aperture that is aligned with the chamber (242), and wherein
the chamber (242) is movable relative to the plate to allow excess powder (20) to
be scraped from the chamber (242).
35. An apparatus (200) as in claim 19, wherein the hopper is a primary hopper (206) and
further comprising a secondary hopper (218) disposed above the pri- mary hopper (206)
to transfer powder (20) to the primary hopper (206).
36. An apparatus (200) as in claim 35, further comprising a shaking mechanism to vibrate
the secondary hopper (218).
37. An apparatus (200) as in claim 28, wherein the chamber is formed in a change tool
(274), and wherein the change tool (274) is removably coupled to the rotatable member
(304).
1. Verfahren für den Transport von feinem Pulver (20), umfassend:
das Platzieren des feinen Pulvers (20) in einem Fülltrichter (12) mit einer daran
befindlichen Öffnung (18);
das Vibrieren eines Elements (28), welches zum Vibrieren gebracht werden kann, in
dem feinen Pulver (20) in der Nachbarschaft der Öffnung (18);
das Vibrieren des Elements (28), welches zum Vibrieren gebracht werden kann, in einer
Auf- und Abbewegung bezüglich des Pulvers (20) in dem Fülltrichter (12);
wobei das Element (28, 210), welches zum Vibrieren gebracht werden kann, mit einer
Frequenz im Bereich von ungefähr 1 000 Hz bis ungefähr 180 000 Hz zum Vibrieren gebracht
wird; und
das Aufnehmen von wenigstens einem Teil des aus der Öffnung (18) austretenden feinen
Pulvers (20) in einer Kammer (24), in der das aufgenommene Pulver (20) ausreichend
dekomprimiert wird, sodass es bei dem Entfernen aus der Kammer (24) dispergiert werden
kann.
2. Verfahren nach Anspruch 1, wobei das Element (28, 210), welches zum Vibrieren gebracht
werden kann, an ein Ultraschallhorn gekoppelt ist, und wobei der Schritt des Vibrierens
das Betätigen des Ultraschallhorns umfasst.
3. Verfahren nach Anspruch 1, wobei das Element (28), welches zum Vibrieren gebracht
werden kann, ein distales Ende (29) aufweist, welches nahe der Öffnung (18) platziert
ist, und wobei das distale Ende (29) ein daran befestigtes Endelement (240) aufweist,
welches über der Kammer (24) zum Vibrieren gebracht wird.
4. Verfahren nach Anspruch 3, wobei das Endelement (240) in vertikalem Abstand von der
Kammer (24) in einer Entfernung im Bereich von ungefähr 0,01 mm bis ungefähr 10 mm
angeordnet ist.
5. Verfahren nach Anspruch 1, welches darüber hinaus das Bewegen des Elements (28) über
die Öffnung (18) umfasst, während das Element zum Vibrieren gebracht wird.
6. Verfahren nach Anspruch 5, welches darüber hinaus das Schieben des Elements (28, 210)
entlang der Öffnung (18) mit einer Geschwindigkeit von weniger als ungefähr 100 cm/s
umfasst.
7. Verfahren nach Anspruch 1, welches darüber hinaus das periodische Ebnen des Pulvers
(20) innerhalb des Fülltrichters (12) umfasst.
8. Verfahren nach Anspruch 7, wobei der Schritt des Ebnens das Platzieren eines hervorstehenden
Elements (30, 244) an dem Element (28, 210), welches zum Vibrieren gebracht werden
kann, an einer Stelle umfasst, die sich in einem Abstand von dem distalen Ende (29)
des Elements (28, 210), welches zum Vibrieren gebracht werden kann, befindet.
9. Verfahren nach Anspruch 1, wobei zahlreiche Kammern (24, 52) mit der Öffnung (18,
56) ausgerichtet sind, und welches darüber hinaus das Bewegen des Elements (28, 60),
welches zum Vibrieren gebracht werden kann, entlang der Öffnung (18, 56) umfasst,
damit sich dieses über jede Kammer (24, 52) bewegt.
10. Verfahren nach Anspruch 1, wobei das feine Pulver (20) ein Medikament umfasst, welches
einzelne Partikel umfasst, die eine mittlere Größe im Bereich von ungefähr 1 µm bis
100 µm aufweisen.
11. Verfahren nach Anspruch 1, wobei der Aufnahmeschritt darüber hinaus das Ansaugen von
Luft durch die unter der Öffnung (18, 56) positionierte Kammer (24, 52) umfasst, wobei
die angesaugte Luft dazu beiträgt, das feine Pulver (20) in die Kammer (24, 52) zu
saugen.
12. Verfahren nach Anspruch 1, welches darüber hinaus das Überführen des aufgenommenen
Pulvers (20) von der Kammer (24, 52) zu einem Aufnahmebehälter umfasst.
13. Verfahren nach Anspruch 12, wobei der Überführungsschritt das Einführen eines komprimierten
Gases in die Kammer (24, 52) umfasst, um das aufgenommene Pulver (20) in den Aufnahmebehälter
auszustoßen.
14. Verfahren nach Anspruch 1, welches darüber hinaus das Einstellen der Menge des aufgenommenen
Pulvers (20) auf eine Dosiereinheitsmenge umfasst.
15. Verfahren nach Anspruch 14, wobei der Einstellschritt das Vorsehen einer dünnen Platte
(284) unter dem Fülltrichter (12) umfasst, wobei die Platte (284) eine Öffnung (286)
aufweist, die mit der Kammer (24, 242) ausgerichtet ist, und darüber hinaus das Bewegen
der Kammer (24, 242) bezüglich der Platte (284) umfasst, um überschüssiges Pulver
(20) von der Kammer (24, 242) zu schaben.
16. Verfahren nach Anspruch 1, wobei der Fülltrichter (12) ein primärer Fülltrichter (206,
306) ist, und wobei der Platzierschritt das Überführen des Pulvers (20) von einem
sekundären Fülltrichter (218) zu dem primären Fülltrichter (206, 306) umfasst.
17. Verfahren nach Anspruch 16, welches darüber hinaus das Vibrieren des sekundären Fülltrichters
(218) umfasst, um das Pulver (20) zu dem primären Fülltrichter (206, 306) zu überführen.
18. Verfahren nach Anspruch 1, welches darüber hinaus das Abgeben des Pulvers (20) aus
der Kammer (242) sowie das Verändern der Größe der Kammer (242) umfasst.
19. Vorrichtung (200) zum Transportieren eines feinen Pulvers (20), umfassend:
einen Fülltrichter (12) mit einer daran befindlichen Öffnung (18), wobei der Fülltrichter
(12) dazu ausgebildet ist, das feine Pulver (20) aufzunehmen;
wenigstens eine Kammer (242), die beweglich ist, um zu ermöglichen, dass die Kammer
(242) in nächster Nachbarschaft der Öffnung (18) platziert wird;
ein Element (210), welches zum Vibrieren gebracht werden kann, umfassend ein proximales
Ende und ein distales Ende (29), wobei das Element (210), welches zum Vibrieren gebracht
werden kann, innerhalb des Fülltrichters (12) derart positionierbar ist, dass sich
das distale Ende (29) nahe der Öffnung (18) befindet; und
ein Vibrationsmotor (208), um das Element (210), welches zum Vibrieren gebracht werden
kann, zum Vibrieren zu bringen, wenn es sich in dem feinen Pulver (20) befindet,
wobei der Vibrationsmotor (208) dafür ausgelegt ist, das Element (210), welches zum
Vibrieren gebracht werden kann, bezüglich des Pulvers (20) in einer Aufund Abbewegung
zum Vibrieren zu bringen; und
wobei der Vibrationsmotor (208) dafür ausgelegt ist, das Element (210), welches zum
Vibrieren gebracht werden kann, mit einer Frequenz im Bereich von ungefähr 1 000 Hz
bis ungefähr 180 000 Hz zum Vibrieren zu bringen.
20. Vorrichtung nach Anspruch 19, welche ferner einen Mechanismus (216, 217) umfasst,
um das Element (210), welches zum Vibrieren gebracht werden kann, über die Kammer
(242) zu verschieben.
21. Vorrichtung (200) nach Anspruch 20, welche darüber hinaus ein drehbares Element (204)
mit einer Mehrzahl von Kammern (242) an seiner Peripherie aufweist, die mit der Öffnung
(18, 56) ausgerichtet werden können, und wobei der Verschiebemechanismus (216, 217)
dazu konfiguriert ist, das Element (210), welches zum Vibrieren gebracht werden kann,
entlang der Öffnung (18, 56) zu verschieben, so dass sich das Element (210), welches
zum Vibrieren gebracht werden kann, über jede Kammer (242) bewegt.
22. Vorrichtung (200) nach Anspruch 20, wobei der Verschiebemechanismus (216, 217) einen
Linearantriebsmechanismus umfasst, welcher das Element (210), welches zum Vibrieren
gebracht werden kann, an der Öffnung mit einer Geschwindigkeit von weniger als ungefähr
100 cm/s entlang schiebt.
23. Vorrichtung (200) nach Anspruch 19, wobei der Vibrator ein Ultraschallhorn umfasst,
welches das Element bezüglich des Pulvers (20) in einer Auf- und Abbewegung vibrieren
lässt.
24. Vorrichtung (200) nach Anspruch 23, wobei das Element, welches zum Vibrieren gebracht
werden kann, von zylindrischer Form ist und einen Durchmesser im Bereich von ungefähr
1,0 mm bis ungefähr 10 mm aufweist.
25. Vorrichtung (200) nach Anspruch 24, welche darüber hinaus ein Endelement (240) am
distalen Ende (29) des Elements (210), welches zum Vibrieren gebracht werden kann,
aufweist.
26. Vorrichtung (200) nach Anspruch 25, wobei sich das Endelement (240) radial von dem
Element, welches zum Vibrieren gebracht werden kann, erstreckt.
27. Vorrichtung (200) nach Anspruch 25, welche darüber hinaus ein Pulverebnungselement
(244) umfasst, das in Abstand zu dem Endelement (240) angeordnet ist.
28. Vorrichtung (200) nach Anspruch 19, wobei die Kammer (242) innerhalb eines drehbaren
Elements (304) angeordnet ist, welches in einer ersten Position platziert ist, in
der die Kammer (242) mit der Öffnung ausgerichtet ist, und in einer zweiten Position,
in der die Kammer mit einem Aufnahmebehälter (328) ausgerichtet ist.
29. Vorrichtung (200) nach Anspruch 19, welche darüber hinaus eine Öffnung am Boden der
Kammer (242) und eine Vakuumquelle in Verbindung mit der Öffnung umfasst, um dazu
beizutragen, das feine Pulver (20) aus dem Fülltrichter (306) und in die Kammer (242)
zu saugen.
30. Vorrichtung (200) nach Anspruch 29, welche darüber hinaus einen über der Öffnung angeordneten
Filter (276) aufweist.
31. Vorrichtung (200) nach Anspruch 29, welche darüber hinaus eine Quelle für komprimiertes
Gas in Verbindung mit der Öffnung aufweist, um das aufgenommene Pulver (20) aus der
Kammer (242) in den Aufnahmebehälter (328) auszustoßen.
32. Vorrichtung (200) nach Anspruch 31, welche darüber hinaus ein Steuerelement zur Steuerung
der Betätigung der Gasquelle und der Vakuumquelle umfasst.
33. Vorrichtung (200) nach Anspruch 28, welche darüber hinaus eine Mehrzahl von Fülltrichtern
umfasst, welche über einer Mehrzahl von drehbaren Elementen angeordnet sind, welche
jeweils eine Mehrzahl von Kammern (242) umfassen, und welche darüber hinaus eine Mehrzahl
von Elementen und eine Mehrzahl von Vibratoren umfasst, um die Elemente vibrieren
zu lassen.
34. Vorrichtung (200) nach Anspruch 19, welche darüber hinaus eine unter dem Fülltrichter
angeordnete Platte aufweist, wobei die Platte eine Öffnung umfasst, die mit der Kammer
(242) ausgerichtet ist, und wobei die Kammer (242) bezüglich der Platte bewegbar ist,
damit überschüssiges Pulver (20) von der Kammer (242) geschabt werden kann.
35. Vorrichtung (200) nach Anspruch 19, wobei der Fülltrichter ein primärer Fülltrichter
(206) ist, und welche darüber hinaus einen sekundären Fülltrichter (218) aufweist,
der über dem primären Fülltrichter (206) angeordnet ist, um Pulver (20) zu dem primären
Fülltrichter (206) zu überführen.
36. Vorrichtung (200) nach Anspruch 35, welche darüber hinaus einen Rüttelmechanismus
umfasst, um den sekundären Fülltrichter (218) zum Vibrieren zu bringen.
37. Vorrichtung (200) nach Anspruch 28, wobei die Kammer in einem Wechselwerkzeug (274)
angeordnet ist, und wobei das Wechselwerkzeug (274) entfernbar an das drehbare Element
(304) gekoppelt ist.
1. Procédé pour transporter une poudre fine (20), comprenant :
la mise en place de la poudre fine (20) dans une trémie (12) dans laquelle se trouve
une ouverture (18) ;
la mise en vibration d'un élément vibrant (28) dans la poudre fine (20) au voisinage
de l'ouverture (18) ;
la mise en vibration de l'élément vibrant (28) en un mouvement de montée et de descente
par rapport à la poudre (20) dans la trémie (12) ;
dans lequel l'élément vibrant est mis en vibration à une fréquence comprise dans la
plage d'environ 1000 Hz à environ 180 000 Hz ; et
la capture d'au moins une portion de la poudre fine (20) sortant de l'ouverture (18)
dans une chambre (24), dans laquelle la poudre capturée (20) est suffisamment décompactée
pour pouvoir être dispersée en étant enlevée de la chambre (24).
2. Procédé selon la revendication 1, dans lequel l'élément vibrant (28, 210) est couplé
à un cornet à ultrasons, et dans lequel l'étape de mise en vibration comprend l'actionnement
du cornet à ultrasons.
3. Procédé selon la revendication 1, dans lequel l'élément vibrant (28) comporte une
extrémité distale (29) qui est placée à proximité de l'ouverture (18), et dans lequel
l'extrémité distale (29) comporte une pièce d'extrémité (240) qui lui est fixée et
qui est mise en vibration au-dessus de la chambre (24).
4. Procédé selon la revendication 3, dans lequel la pièce d'extrémité (240) est espacée
verticalement de la chambre (24) d'une distance comprise dans la plage d'environ 0,01
mm à environ 10 mm.
5. Procédé selon la revendication 1, comprenant en outre le déplacement de l'élément
(28) à travers l'ouverture (18) tout en faisant vibrer l'élément.
6. Procédé selon la revendication 5, comprenant en outre la translation de l'élément
(28, 210) le long de l'ouverture (18) à une vitesse qui est inférieure à environ 100
cm/s.
7. Procédé selon la revendication 1, comprenant en outre le nivellement périodique de
la poudre (20) dans la trémie (12).
8. Procédé selon la revendication 7, dans lequel l'étape de nivellement comprend la mise
en place d'une pièce en saillie (30, 244) sur l'élément vibrant (28, 210) dans un
emplacement espacé d'une extrémité distale (29) de l'élément vibrant (28, 210).
9. Procédé selon la revendication 1, dans lequel des chambres multiples (24, 52) sont
alignées avec l'ouverture (18, 56), et comprenant en outre le déplacement de l'élément
vibrant (28, 60) le long de l'ouverture (18, 56) afin qu'il passe au-dessus de chaque
chambre (24, 52).
10. Procédé selon la revendication 1, dans lequel la poudre fine (20) comprend un médicament
composé de particules individuelles ayant une dimension moyenne dans la plage d'environ
1 µm à 100 µm.
11. Procédé selon la revendication 1, dans lequel l'étape de capture comprend en outre
l'aspiration d'air à travers la chambre (24, 52) qui est positionnée en dessous de
l'ouverture (18, 56), dans lequel l'air aspiré aide à introduire en l'aspirant la
poudre fine (20) dans la chambre (24, 52).
12. Procédé selon la revendication 1, comprenant en outre le transfert de la poudre capturée
(20) de la chambre (24, 52) à un réceptacle.
13. Procédé selon la revendication 12, dans lequel l'étape de transfert comprend l'introduction
d'un gaz comprimé dans la chambre (24, 52) pour expulser la poudre capturée (20) jusque
dans le réceptable.
14. Procédé selon la revendication 1, comprenant en outre l'ajustement de la quantité
de poudre capturée (20) afin qu'elle soit égale à une quantité de dosages unité.
15. Procédé selon la revendication 14, dans lequel l'étape d'ajustement comprend la mise
en place d'une plaque mince (284) en dessous de la trémie (12), la plaque (284) ayant
un orifice (286) qui est aligné avec la chambre (24, 242), et comprenant en outre
le déplacement de la chambre (24, 242) par rapport à la plaque (284) afin de racler
la poudre excédentaire (20) de la chambre (24, 242).
16. Procédé selon la revendication 1, dans lequel la trémie (12) est une trémie primaire
(206, 306), et dans lequel l'étape de mise en place comprend le transfert de la poudre
(20) d'une trémie secondaire (218) à la trémie primaire (206, 306).
17. Procédé selon la revendication 16, comprenant en outre la mise en vibration de la
trémie secondaire (218) pour transférer la poudre (20) à la trémie primaire (206,
306).
18. Procédé selon la revendication 1, comprenant en outre la distribution de la poudre
(20) à partir de la chambre (242) et la modification de la dimension de la chambre
(242).
19. Appareil (200) pour transporter une poudre fine (20), comportant :
une trémie (12) dans laquelle se trouve une ouverture (18), la trémie (12) étant conçue
pour recevoir la poudre fine (20) ;
au moins une chambre (242) qui est mobile pour permettre à la chambre (242) d'être
placée à proximité étroite de l'ouverture (18) ;
un élément vibrant (210) ayant une extrémité proximale et une extrémité distale (29),
l'élément vibrant (210) pouvant être positionné dans la trémie (12) de façon que l'extrémité
distale (29) soit proche de l'ouverture (18) ; et un moteur vibratoire (208) destiné
à faire vibrer l'élément vibrant (210) lorsqu'il se trouve dans la poudre fine (20),
le moteur vibratoire (208) étant conçu pour faire vibrer l'élément vibrant (210) en
un mouvement de montée et de descente par rapport à la poudre (20) ; et
le moteur vibratoire (208) étant conçu pour faire vibrer l'élément vibrant (210) à
une fréquence dans la plage d'environ 1000 Hz à environ 180 000 Hz.
20. Appareil selon la revendication 19, comportant en outre un mécanisme (216, 217) destiné
à translater l'élément vibrant (210) au-dessus de la chambre (242).
21. Appareil (200) selon la revendication 20, comportant en outre un organe rotatif (204)
le long de la périphérie duquel se trouvent plusieurs chambres (242) qui peuvent être
alignées avec l'ouverture (18, 56), et dans lequel le mécanisme de translation (216,
217) est configuré de façon à translater l'élément vibrant (210) le long de l'ouverture
(18, 56) afin que l'élément vibrant (210) passe au-dessus de chaque chambre (242).
22. Appareil (200) selon la revendication 20, dans lequel le mécanisme de translation
(216, 217) comporte un mécanisme d'entraînement linéaire qui translate l'élément vibrant
(210) le long de l'ouverture à une vitesse qui est inférieure à environ 100 cm/s.
23. Appareil (200) selon la revendication 19, dans lequel le vibrateur comporte un cornet
à ultrasons qui fait vibrer l'élément dans ledit mouvement de montée et de descente
par rapport à la poudre (20).
24. Appareil (200) selon la revendication 23, dans lequel l'élément vibrant est de géométrie
cylindrique et a un diamètre dans la plage d'environ 1,0 mm à environ 10 mm.
25. Appareil (200) selon la revendication 24, comportant en outre une pièce d'extrémité
(240) située à l'extrémité distale (29) de l'élément vibrant (210).
26. Appareil (200) selon la revendication 25, dans lequel la pièce d'extrémité (240) s'étend
radialement à partir de l'élément vibrant.
27. Appareil (200) selon la revendication 25, comportant en outre un élément (244) de
nivellement de la poudre espacé autour de la pièce d'extrémité (240).
28. Appareil (200) selon la revendication 19, dans lequel la chambre (242) est disposée
à l'intérieur d'un organe rotatif (304) qui est placé dans une première position dans
laquelle la chambre (242) est alignée avec l'ouverture, et une seconde position dans
laquelle la chambre (242) est alignée avec un réceptacle (328).
29. Appareil (200) selon la revendication 19, comportant en outre un orifice dans le fond
de la chambre (242), et une source de dépression en communication avec l'orifice pour
aider à aspirer la poudre fine (20) depuis la trémie (306) jusque dans la chambre
(242).
30. Appareil (200) selon la revendication 29, comportant en outre un filtre (276) disposé
à travers l'orifice.
31. Appareil (200) selon la revendication 29, comportant en outre une source de gaz comprimé
en communication avec l'orifice afin d'éjecter la poudre capturée (20) depuis la chambre
(242) jusque dans le réceptacle (328).
32. Appareil (200) selon la revendication 31, comportant en outre un dispositif de commande
destiné à commander l'actionnement de la source de gaz et de la source de dépression.
33. Appareil (200) selon la revendication 28, comportant en outre plusieurs trémies disposées
au-dessus de plusieurs organes rotatifs qui comprennent chacun plusieurs chambres
(242), et comportant en outre plusieurs éléments et plusieurs vibrateurs destinés
à faire vibrer les éléments.
34. Appareil (200) selon la revendication 19, comportant en outre une plaque disposée
en dessous de la trémie, la plaque ayant un trou qui est aligné avec la chambre (242),
et dans lequel la chambre (242) est mobile par rapport à la plaque afin de permettre
à de la poudre excédentaire (20) d'être raclée de la chambre (242).
35. Appareil (200) selon la revendication 19, dans lequel la trémie est une trémie primaire
(206) et comportant en outre une trémie secondaire (218) disposée au-dessus de la
trémie primaire (206) pour transférer de la poudre (20) à la trémie primaire (206).
36. Appareil (200) selon la revendication 35, comportant en outre un mécanisme de secouage
destiné à faire vibrer la trémie secondaire (218).
37. Appareil (200) selon la revendication 28, dans lequel la chambre est formée dans un
outil à changement (274), et dans lequel l'outil à changement (274) est relié de façon
amovible à l'organe rotatif (304).