BACKGROUND
Technical Field
[0001] The invention relates to an apparatus for dispensing a plurality of fluids, comprising
a support, such as a turntable or a linear table, a plurality of containers for holding
a fluid mounted on the support, pumps connected to respective containers, a common
actuator for sequentially operating the pumps, stirring elements mounted rotatably
inside and extending from the containers, and a drive mechanism for rotating the stirring
elements, wherein the support on the one hand and the actuator and drive mechanism
on the other are movable relative to each other.
Background of the Related Art
[0002] EP 1 090 679 relates to an apparatus for dispensing viscous fluids comprising a turntable rotatable
around an axis of rotation. A plurality of containers containing the fluid to be dispensed
are attached to the turntable in positions spaced about the circumference of the turntable.
A pump is associated with each container for dispensing fluid therefrom.
[0004] WO 2005/107933 relates to an apparatus for dispensing a plurality of powders, such as colorants
for paint, caulking or grout or components of cosmetics, comprising a plurality of
containers for holding the powders, a plurality of metering powder pumps, connected
to the containers. The embodiment shown in Figures 10A to 10D of
WO 2005/107933 comprises a system for stirring the contents of the containers (4). This system comprises,
for each of the containers (4), a stirrer (50) having a shaft (51) rotatably mounted
in the bottom wall of the respective container (4) and through the pump (3) beneath.
The section of the shaft (51) that is inside the container (4) comprises stirring
elements, such as flexible rods (52A) resting on the inner wall of the respective
container (Figure 10C) or rigid rods (52B) shaped to encompass a substantial part
of the volume of the respective container (4; Figure 10D). The end of the shaft (51)
is provided with a hook (54) for engaging a drive mechanism (53) attached to the frame
of the apparatus (1) and located beneath the dispensing position. The drive mechanism
(53) comprises a plate (55), a motor (56), guides (57) for supporting a rotational
motion of the plate (55), and an alignment ramp (58) located next to (and upstream
from) the plate (55). The plate (55) is provided with a pair of studs (59) for engaging
the hook (54). During operation, the containers (4) will be rotated about the central
axis of the apparatus (1). When the required container (4) has reached the dispensing
position, the containers (4) are brought to a halt and the plate (5) of the drive
mechanism (53) is rotated. During rotation, the studs (59) will engage the hook (54)
and the shaft (51) of the stirrer (50) will be rotated thus stirring the contents
of the container (4).
[0005] It is an object of the present invention to provide an improved drive mechanism for
sequentially stirring the contents of the containers.
SUMMARY OF THE DISCLOSURE
[0006] To this end, the drive mechanism for rotating the stirring elements comprises a protrusion
movable between at least a first, extended position for engaging a stirring element
and a second, retracted position.
[0007] Thus, when the support, e.g. a turntable, rotates a next container and pump to the
dispensing position, collision between the stirring elements and the drive mechanism
is reduced or avoided altogether.
[0008] In one aspect, the drive mechanism is rotatable and the protrusion is extended when
the mechanism is rotated in one direction and is retracted when the mechanism is rotated
in the other direction.
[0009] In a further aspect, the mechanism comprises two components rotatable relative to
each other and the protrusion is pivotally mounted on the component facing the containers
and engages the other component, such that relative rotation of the two components
results in extending or retracting, respectively, of the protrusion.
[0010] In a another aspect, the pumps are piston pumps and the actuator comprises a lead
screw and a gripper for engaging the piston pumps and mounted on the lead screw by
means of a nut or internal thread. The gripper slidingly abuts a surface of the apparatus,
e.g. an inner wall of the frame, cover or door, which surface extends parallel to
the lead screw, thus substantially preventing rotation of the gripper relative to
the lead screw. Alternatively or additionally, the surface comprises a guide, such
as a channel, groove or slit, for accommodating part of the gripper.
[0011] In these configurations, which can also be applied in embodiments not having the
stirring elements and drive mechanism specified above, a separate guiding rod, as
used in known actuators, can be omitted resulting in a simplified yet robust design.
[0012] In another aspect, the apparatus comprises a sensor stationary relative to the actuator
and a plurality of markers, preferably one for each pump, on the support and operatively
associated with the sensor. E.g., the sensor is a proximity sensor mounted on the
frame and the markers are extensions of or openings or recesses in the support. This
configuration too, can be applied in embodiments not having the stirring elements
and drive mechanism specified above.
[0013] Within the framework of the invention, the term "fluid" is defined as any material
that can flow and that can be dispensed by the apparatus according to the present
invention. Examples of fluids include liquids, pastes, granulates, and powders. The
term "stirring element" includes stirring elements comprising two or more components,
e.g. comprising a transmission.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014]
Figure 1 is a perspective view of an apparatus for dispensing fluids according to
the present invention, with its external cover removed;
Figures 2A to 2C are perspective views of a mechanism for sequential stirring used
in the apparatus in Figure 1;
Figure 3 is a perspective view of a mechanism for operating the piston pumps in the
apparatus in Figure 1;
Figures 4A and 4B are perspective views of means for measuring the position of the
turntable relative to the dispensing position as used in the apparatus in Figure 1.
[0015] The drawings are not necessarily to scale and details, which are not necessary for
understanding the present invention, may have been omitted.
DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS
[0016] Figure 1 shows an example of an apparatus 1 for dispensing a plurality of fluids,
such as (components of) paints, paint colorants, hair dyes, shampoos, foundations,
and the like. It can be used for dispensing numerous recipes of the said products
and can be located e.g. at a retailer of decorative paints, a hairdresser, or a spa,
respectively.
[0017] This particular dispensing apparatus 1 is an automated version and includes a horizontal
turntable 2, with a plurality of containers 4 and piston pumps 3 mounted along its
circumference. The turntable 2 can be rotated between discrete positions, e.g. sixteen
positions including a dispensing position.
[0018] The apparatus 1 includes a frame 5 of e.g. aluminium extrusion profiles on which
sheets (not shown) of metal or a polymer (transparent, translucent or opaque) can
be attached by means of e.g. screws. A control panel comprising a display and a small
keyboard for entering information, such as customer data and recipes, is typically
mounted on one side of the frame 5, next to a door or front section 6. This front
section 6 contains a computer (not shown) for storing the said information and for
driving the turntable 2 and actuators for operating the pumps 3, as will be explained
in more detail with reference to Figure 3.
[0019] The pumps 3, shown in more detail in Figure 2A, are known in the art and comprise,
at least in this example, a cylinder 10 and a piston, mounted inside the cylinder
10 and provided with a piston rod 11, which, on its upper end, is provided with a
washer or flange 12.
[0020] The cylinder 10 is mounted in the top part of a pump housing 13, containing a known
valve member, e.g. a disc, ball or cylinderal valve, which can be operated by means
of a lever 14. In the intake position of this lever 14, the cylinder 10 communicates
with a container 4 and can be filled with a desired amount of the fluid from the container
4 by moving the flange 12 and thus the piston upwards over a desired or predetermined
length. As soon as a selected amount of fluid has been taken in, the valve member
can be rotated to a open position. In this position, the cylinder 10 communicates
with a dispensing opening in the bottom surface of the pump housing 13 and the fluid
can be dispensed by moving the flange 12 downwards.
[0021] Details regarding the turntable, pumps and the procedure for driving these components,
are disclosed in, for instance, international application
WO 03/083334, European patent application
0 992 450, and European patent application
0 800 858.
[0022] Each of the containers 4 comprises a stirrer having a shaft rotatably mounted in
the bottom wall of the respective container 4. The section of the shaft that is inside
the container 4 (and thus hidden from view) comprises stirring elements, such as blades
or rods shaped to encompass a substantial part of the volume of the respective container.
The end of the shaft is provided with a hook 20 to be engaged by a drive mechanism
21, shown in Figures 2A to 2C, attached to the frame 5 of the apparatus 1 and located,
in this example, one or more, e.g. three positions away from the dispensing position.
[0023] The drive mechanism 21 comprises an electric motor 22, a housing 23 accommodating
a rotatable element (hidden from view), e.g. e friction disc or (semi)circular rack,
coupled to the shaft of the electric motor 22. The mechanism 21 further comprises
a lid 24 resilient pressed onto the upper rim of the housing 23 by means of a screw
25 and a spring washer rotatably attached to e.g. the rotatable element. A cam 26
is pivotally mounted in the lid 24 and engages the rotatable element, e.g. by means
of a curved friction surface or teeth. When the rotatable element is driven in the
clockwise direction (in the embodiment in the figures and in top view), the cam 26
is rotated about 90 degrees and thus extended from the lid 24. Once extended, the
cam 26 couples the lid 24 to the rotatable element and the lid 24 and the extended
cam 26 start rotating, while the housing 23 remains stationary. The cam 26 will engage
the hook 20 of the stirrer of the container 4 above it and will thus stir the contents
of the container 4. When the direction of rotation of the electric motor is reversed,
the rotatable element is driven in the counter-clockwise direction and the cam 26
is rotated about 90 degrees in opposite direction and thus retracted.
[0024] Because the cam only extends during stirring, contact between the drive mechanism
and the stirrers when the turntable is rotated from one position to the next is prevented.
[0025] As mentioned above and as shown in Figure 3, actuators 30, 31 for, respectively,
the valve and the piston of the pumps are located on the inside of the front section
6. The actuator 31 for the piston comprises and electric motor 32, a lead screw 33
formed on or rigidly connected to the shaft 34 of the electric motor 32, and a gripper
35. The gripper 35 is shaped like a claw, which allows unobstructed horizontal movement
of the pumps 3, but engages, when it moves vertically, the flange 12 and hence the
piston of the pump 3 in front of it, i.e. the pump 3 at the dispensing position. The
gripper 35 is mounted on the lead screw by means of a nut or internal thread, i.e.
rotating the lead screw 33 results in translation of the gripper 35 and thus of the
piston in the pump 3 at the dispensing position. To prevent rotation of the gripper
35 relative to the lead screw 33, the gripper 35 slidingly abuts a surface of the
apparatus 1, in this example the inner wall of the front section 6, which surface
extends parallel to the lead screw 3. In this example, the width of the side of the
gripper 35 facing the inner wall of the front section 6 is twice the distance between
the lead screw 33 and the surface.
[0026] As shown in Figures 4A and 4B, the apparatus 1 further comprises a proximity sensor
40 mounted on the frame 5 and a plurality of recesses 41, one for each pump 3, in
the turntable 2. One of the recesses, indicated by numeral 42, has a length, seen
along the circumference of the turntable 2, that is at least twice, e.g. trice that
of the other recesses 41 and serves as a reference for the positions of the pumps
3 on the turntable 2.
[0027] During operation, the turntable is rotated about its central axis until it is established
by means of the proximity sensor and the motor driving the turntable that the required
pump has reached the dispensing position. Subsequently, the actuator for the pump
and the drive mechanism for the stirrer are activated as described above, resulting
in simultaneous dispensing from one container while stirring the contents of another
container. Alternatives include postponing stirring to periods when no dispensing
takes place (which enables more systematic stirring) or simultaneous dispensing from
and stirring of the same container (especially advantageous with powders).
[0028] The drive mechanism, actuator and sensor require relatively few components while
maintaining or even improving the reliability of the apparatus.
[0029] As a matter of course, this disclosure is not restricted to the above-disclosed embodiments,
which may be varied in different manners within the spirit and scope of the invention.
For example, the apparatus according to the present invention can be configured as
a linear dispensing apparatus i.e. with the containers aligned is a row. And it can
comprise two or more or concentric circles or rows of containers and a drive mechanism
associated with each circle or row or a drive mechanism that is movable between circles
and rows.
1. An apparatus (1) for dispensing a plurality of fluids, comprising a support, such
as a turntable (2) or a linear table, a plurality of containers (4) for holding a
fluid mounted on the support (2), pumps (3) connected to respective containers (4),
a common actuator (31) for sequentially operating the pumps (3), stirring elements
mounted rotatably inside and extending from the containers (4), and a drive mechanism
(21) for rotating the stirring elements, wherein the support (2) on the one hand and
the actuator (31) and drive mechanism (21) on the other are movable relative to each
other, characterized in that the drive mechanism (21) comprises a protrusion (26) movable between at least a first,
extended position (Figure 2B) for engaging a stirring element (20) and a second, retracted
position (Figure 2A).
2. The apparatus (1) according to claim 1, wherein the drive mechanism (21) is rotatable
and the protrusion (26) is extended when the mechanism (21) is rotated in one direction
and is retracted when the mechanism (21) is rotated in the other direction.
3. The apparatus (1) according to claim 2, wherein the mechanism (21) comprises two components
(24) rotatable relative to each other and wherein the protrusion (26) is pivotally
mounted on the component (24) facing the containers (4) and engages the other component.
4. The apparatus (1) according to any one of the preceding claims, wherein the actuator
(31) and the drive mechanism (21) are positioned to engage the same set of a container
(4) and pump (3).
5. The apparatus (1) according to any one of the preceding claims, comprising concentric
circles or rows of containers (4) and a drive mechanism (21) associated with each
circle or row or a drive mechanism (21) that is movable between circles and rows.
6. The apparatus (1) according to any one of the preceding claims, wherein the pumps
are piston pumps (3) and the actuator (31) comprises a lead screw (33) and a gripper
(35) for engaging the piston pumps (3) and mounted on the lead screw (33) by means
of a nut or internal thread.
7. The apparatus (1) according to claim 6, wherein the gripper (35) slidingly abuts a
surface of the apparatus (1) that extends parallel to the lead screw (33), thus substantially
preventing rotation of the gripper (35) relative to the lead screw (33).
8. The apparatus (1) according to claim 7, wherein the width of the side of the gripper
(35) facing the surface is larger, preferably at least 50% larger than the distance
between the lead screw (33) and the surface.
9. The apparatus (1) according to claim 7 or 8, wherein the surface comprises a guide,
such as a channel, groove or slit, for accommodating part of the gripper (35).
10. The apparatus (1) according to any one of the claims 6-9, wherein the actuator (31)
comprises an electric motor (32) and the lead screw (33) is formed on or rigidly connected
to the shaft of the electric motor (32).
11. The apparatus (1) according to any one of the preceding claims, comprising a sensor
(40) stationary relative to the actuator (31) and a plurality of markers (41, 42),
preferably one for each pump (3), on the support (2) and operatively associated with
the sensor (40).
12. The apparatus (1) according to claim 11, wherein the sensor is a proximity sensor
(40) and the markers are extensions of or openings or recesses (41, 42) in the support
(2).
13. The apparatus according to claim 11 or 12, wherein at least one of the markers (42)
has a dimension, seen in the direction of relative movement between the support (2)
and the actuator (31), different from the other markers (41).
14. The apparatus (1) according to any one of the preceding claims, wherein the support
is a turntable (2) rotatable about an axis of rotation and the containers (4) are
arranged in a circle or part of a circle.