Object of the Invention
[0001] The present invention refers to a roving frame for the formation and delivery of
roving bobbins, of the type comprising a plurality of roving supply devices which,
with the aid of rotating fins and a pressure finger for the guiding of the rovings,
form roving bobbins on tubes coupled on rotating barbs associated to a shiftable bedplate;
the bedplate being able to shift from a first end position in the roving bobbin formation
area and a second end position, shifted toward the rear area of the machine in which
the doffing change or automatic replacement of bobbin-bearing tubes with empty tubes
is carried out.
Background of the Invention
[0002] There are currently different roving frames on the market enabling the formation
of roving bobbins on empty tubes, the automatic replacement of the roving bobbins
with empty tubes and, subsequently, the shifting of the formed bobbins toward an extraction
area.
[0003] The known roving frames use different devices for carrying out the replacement of
the roving bobbins with empty tubes on which new bobbins will be formed.
[0004] Thus, for example, in German patent DE 3,936,518 and in US patent 5,222,350, which
are the patent documents most closely related to the device for replacing bobbins
for empty tubes used in the roving frame of the present invention, the support or
bedplate on which the formation of the bobbins is carried out describes a vertical
movement in the bobbin formation area, a horizontal movement for shifting the formed
roving bobbins toward a rear area of the machine, and vertical movements for carrying
out the replacement of full bobbins with empty bobbins in said rear area with the
aid of an overhead conveyor.
[0005] In said US patent 5,222,350, the vertical shifting of the bedplate is carried out
by means of end rotating spindles vertically arranged and linked to one another by
gears associated to a common drive shaft. The horizontal movement of the bedplate
is likewise carried out by means of rotating spindles horizontally arranged and linked
to one another by means of gears associated to a common drive shaft.
[0006] In this case, the transmission of movements, both horizontal and vertical, has a
certain rigidity and constructive complexity.
[0007] In other roving frames, such as those disclosed in European patents EP 0 906 548
and EP 0 912 781, the replacement of bobbins with empty tubes is carried out in an
area very close to the bobbin formation area, a problem of interference in the movements
of the bobbins and of the empty tubes being able to arise during the replacement thereof.
[0008] One of the drawbacks of these roving frames, in reference to the replacement of bobbins
with empty tubes, is the risk that some of them may be arranged in an incorrect position,
which could cause damages in the machine as the latter lacks suitable safety members
for detecting this type of events.
[0009] On the other hand, these roving frames have an aspiration circuit which is responsible
for removing those fibers or particles which have become detached from the rovings
from the feed area.
[0010] The air used in this operation is unavoidably heated due to the pressure to which
it is subjected, and it is passed through a filter which retains the lint or detached
fibers of the rovings.
[0011] Currently, once the air is filtered, it is not reused but rather released to the
exterior.
[0012] One of the objectives of the present invention is to use this already filtered air
to carry out the cooling of certain members or components of the roving frame, which
usually reach a temperature exceeding that of the air used in the particle or fiber
aspiration and removal circuit.
[0013] For the formation of bobbins, the roving frames have rotating fins and a pressure
finger responsible for guiding the roving on the bobbin being formed.
[0014] This pressure finger usually has a hole for the passage of the roving, as can be
observed in European patent EP 0 533 601, for example.
[0015] The use of a closed hole for the passage of the roving in the pressure finger implies
a drawback when correctly situating the thread with regard to said pressure finger,
since each of the rovings must be introduced through said hole, which implies an excessively
slow operation, especially considering the large number of pressure fingers existing
in each one of the roving frames.
Description of the Invention
[0016] The roving frame object of the present invention has constructive particularities
aimed at achieving greater constructive simplicity, using to that end a modular bedplate
and flexible transmission members for its shifting.
[0017] Another object of the invention is to cool different parts or members of the machine,
using to that end the filtered hot air coming from the aspiration cleaning circuit.
[0018] Another object is to obtain greater simplicity in the positioning of the rovings
in the respective pressure fingers.
[0019] Another of the objects of the invention is to obtain greater safety in the doffing
change, using to that end sensors, which cause the shutdown of the machine in the
event that any of the bobbins or any of the empty tubes are in an incorrect position,
and an overhead conveyor also, assembled in a floating manner and causing the shutdown
of the machine by means of specific sensors before the break of any of the parts of
the roving frame can occur precisely due to the connection between a bobbin and an
empty tube due to its incorrect positioning.
[0020] Another of the objects of the present invention is the use of an overhead conveyor,
occupying a small space inside the machine, maintaining its horizontal position, for
changing full bobbins and empty tubes.
[0021] To that end and according to the invention, the movable bedplate holding the barbs
on which the empty tubes are assembled for the formation of bobbins is made up of
several bedplate sections horizontally aligned and provided on their ends with means
for controlling the horizontal alignment of said successive bedplate sections.
[0022] Said means for controlling the horizontal alignment are made up of fixed sensors
and a fixed bar associated to consecutive bedplate sections such that when consecutive
bedplate sections become misaligned, the bar of one of the sections acts on one of
the sensors of the other section, said sensor causing the shutdown of the roving frame.
[0023] The bedplate sections are assembled on rotating nuts, linked to one another by a
series of flexible gear tooth belt or chain type transmission members.
[0024] Said rotating nuts are assembled on vertical spindles unable to rotate and fixed
to lower carriages assembled with the possibility of longitudinal shifting on sets
of transverse rails.
[0025] Said lower carriages are shifted by flexible dragging means comprising transverse
chain sections or the like fixed to the opposite ends of the carriages and linked
with respective main branches which are notably parallel and vertically arranged in
the front and rear areas of the roving frame.
[0026] These main branches are linked, at least at one of their ends, by means of a chain
section which is actuated by a drive member responsible for causing the shifting of
the main branches in opposite directions, achieving the transverse and simultaneous
shifting of the lower carriages toward the front area or toward the rear area of the
roving frame.
[0027] The cooling circuit used for preventing the excessive heating of certain components
or members of the roving frame, such as motors or electrical control panels, comprisies
a main duct connected to the pneumatic cleaning circuit belonging to the roving frame.
[0028] This main duct of the cooling circuit branches off into a series of branches provided
with outlets through which the air coming from the pneumatic cleaning circuit is projected
towards those members or areas of the roving frame to be cooled.
[0029] Specifically, the main duct of the cooling circuit is connected to a filtered air
outlet defined in the impurity collection tank of the pneumatic cleaning circuit.
[0030] This roving frame furthermore comprises means for the suspended support and with
the possibility of vertical shifting of the overhead conveyor responsible for carrying
out the collection of bobbins delivered by the movable bedplate and the delivery of
empty tubes to said bedplate.
[0031] Said support means enable certain vertical shifting of the overhead conveyor such
that in the event that said overhead conveyor is pushed vertically (due to the interference
between bobbins and/or empty tubes incorrectly positioned during the upward movement
of the bedplate), the actuation of sensors detecting the lifting of said overhead
conveyor occurs, and they cause the shutdown of the roving frame, preventing the breaking
of the overhead conveyor or of any other member of the roving frame.
[0032] Said overhead conveyor has rails defining a closed path for the shifting of a bobbin
holder chain, said rails defining two intermediate, notably parallel sections linked
at their ends by means of a divergent oblique section and two curved and symmetrical
sections, in the manner of a circular segment.
[0033] In turn, the bobbin holder chain is formed of a series of hinge bars the length of
which is greater than the separation existing between the intermediate and parallel
sections of the rails of the overhead conveyor, and notably equal to the radius of
curvature of the symmetrical sections, in the manner of circular segment, defined
in the opposite ends of the rails of said overhead conveyor.
[0034] In addition to reducing the width occupied by the rails, this particularity enables
the branches of the chain which shift on the two sides or intermediate sections of
the rails to be able to describe intermittent and alternating movements since when
one of the branches moves forward, one of the end bars pivots on one of its ends,
whereas the other end of said bar runs along the curved section defined in the corresponding
end of the rails of the overhead conveyor.
[0035] The roving frame of the invention furthermore incorporates sensors which enable automatically
verifying the correct position of the bobbins and of the empty tubes during the doffing
change. These sensors are made up of photoelectric cells arranged at the opposite
ends of the machine and slightly deviated with regard to the alignments formed by
the empty tubes and the bobbins in the collection and delivery positions.
[0036] During the doffing change, the bedplate describes a series of upward or downward
vertical movements and forward and backward horizontal movements in the rear area
of the machine and in an alternating manner, such that in the event that any of the
bobbins or empty tubes are in an incorrect position, the contact thereof and their
deviation or tilt toward a position in which they are detected by the sensors responsible
for automatically verifying the correct position of the bobbins and of the empty tubes
will occur.
[0037] These sensors are connected to an emergency shutdown circuit which causes the shutdown
of the roving frame in the event that this anomaly occurs so that an operator can
place those bobbins or tubes not occupying a correct position in a suitable position.
[0038] According to the invention and as previously discussed, the pressure fingers used
in this roving frame for guiding the rovings during the formation of the bobbin have
features aimed at facilitating the placement of the thread in the hole defined in
the baffle of the pressure finger and assuring that the roving is maintained inside
the hole when its breaking is carried out, once the bobbin is finished.
[0039] To that end, said pressure finger has a rear opening or cut which tangentially accesses
the upper area of said hole, demarcating together with said opening a roving retention
fin having a lateral tilt on its front-upper area, which prevents the roving from
being able to be involuntarily released from said pressure finger.
Description of the Figures
[0040] To complement the description being made and for the purpose of facilitating the
understanding of the features of the invention, a set of drawings is attached to the
present specification in which, with an illustrative and non-limiting character, the
following has been shown:
Figure 1 shows a schematic front elevational view of a portion of the bedplate and
of the means used for its vertical shifting, with an enlarged detail of the means
used for controlling the horizontal position of the successive bedplate sections.
Figures 2 and 3 show respective schematic upper plan views of the means for the horizontal
shifting of the bedplate, the lower carriages being able to be observed in the two
end positions.
Figures 4, 5 and 6 show schematic profile views of the roving frame, sectioned by
a vertical plane and in which the downward vertical and shifting movements of the
bedplate, with the bobbins already formed, toward the rear area of the machine to
carry out the change of doffing, can be observed.
Figures 7a and 7b show respective schematic profile and rear elevational views of
the bedplate holding the bobbins, vertically aligned with the overhead conveyor, the
tubes and bobbins being correctly positioned.
Figures 8a and 8b show respective views similar to the previous ones, in which the
detection by the sensors of one of the empty tubes positioned on the overhead conveyor
in an incorrect position can be observed.
Figures 9a and 9b show respective views similar to the previous ones, in which the
detection by the sensors of the incorrect position of a bobbin which has been incorrectly
positioned on the bedplate after the bobbins have been delivered to the overhead conveyor
can be observed.
Figures 10a and 10b show respective views similar to the previous ones, in which the
detection of an empty tube which has been incorrectly positioned on the overhead conveyor
once the empty tubes have been delivered to the bedplate can be observed.
Figures 11, 12 and 13 show respective profile views of the machine in which the return
of the bedplate by means of a horizontal shifting and a vertical shifting toward the
front area, positioning the empty tubes in the bobbin formation area, can be observed.
Figure 14 shows a plan view of the overhead conveyor in which the rails of said conveyor
and the bobbin holder chain represented with a simple tracing line can be observed.
Figures 15 and 16 show respective plan views of the overhead conveyor during the alternating
forward movement of each one of the branches of the bobbin holder chain.
Figure 17 shows an elevational view of a detail of the overhead conveyor suspended
from the bedplate, being able to observe one of the sensors responsible for detecting
the vertical movement of said overhead conveyor in the event that any bobbins or empty
tubes are incorrectly positioned during the doffing change.
Figure 18 shows a view similar to the previous one in which the actuation of one of
said sensors during the doffing change due to the incorrect position of one of the
empty tubes can be observed.
Figure 19 shows a schematic profile view of the machine with an enlarged detail of
the conveyor vertically shifted and actuating one of the sensors responsible for detecting
said vertical shifting of the overhead conveyor.
Figure 20 shows a schematic rear elevational view of the cooling device connected
to the pneumatic cleaning circuit of the machine.
Figure 21 shows a schematic elevational view of the pressure finger acting on a bobbin,
once the bobbin is finished and immediately after the breaking of the roving has occurred.
Figure 22 shows an enlarged detail of the baffle of the pressure finger.
Figure 23 shows a profile view of the baffle sectioned by a vertical plane.
Preferred Embodiment of the Invention
[0041] As can be seen in Figure 1, the bedplate (1) holding the rotating barbs (2) is made
up of several bedplate sections (3), horizontally aligned and assembled by means of
rotating nuts (4) on vertical spindles (5). Said vertical spindles (5) are unable
to spin and are fixed to lower carriages (6) assembled with the possibility of longitudinal
shifting of a set of transverse rails (7).
[0042] The rotating nuts (4) are linked to one another by a series of flexible gear tooth
belt or chain-type members (8), actuated by a drive member (9).
[0043] Each one of the transmission belts or chains (8) links a pair of successive nuts
(4).
[0044] The rotation of the motor in either direction causes the upward or downward vertical
shifting of the bedplate (1).
[0045] As can be observed in the enlarged detail of Figure 1, the successive sections (3)
of the bedplate (1) respectively have a pair of sensors (10) connected to an emergency
shutdown system and a cantilever bar (11), which selectively acts on one of the sensors
(10) in the event that the successive bedplate sections (3) loose their horizontal
position and define between one another a certain positive or negative angle. Thus,
if a misalignment of any one of the transmission members (8) occurs, the automatic
shutdown of the roving frame will occur.
[0046] The horizontal shifting of the bedplate (1) is generated by flexible dragging means
of the lower carriages (6), said dragging means being observable in Figures 2 and
3.
[0047] These dragging means comprise transverse band or strip sections (12) fixed to the
opposite ends of the carriages (6) and linked to respective main branches (13) which
are notably parallel and longitudinally arranged in the front and rear areas of the
roving frame.
[0048] Said main branches (13) are linked at one of their ends by means of a chain section
(14) on which a drive member (15) acts by means of the corresponding pinion, which
drive member, when rotating in either direction, causes the horizontal shifting of
the carriages (6) toward the front area or toward the rear area of the roving frame,
and which is adjusted to a torque limiter.
[0049] As can be observed in the enlarged detail of Figure 3, the end positions of the carriages
(6) are detected by proximity sensors (16) and mechanical stop to assure the position.
[0050] As can be observed in Figure 4, once the roving bobbins (17) are formed on tubes
(18) assembled on the barbs (2) of the bedplate (1), said bedplate (1) vertically
shifts toward a lower position (Figure 5) and subsequently shifts horizontally over
the transverse rails (7) to be arranged in the rear area of the machine and vertically
facing an overhead conveyor (19) responsible for collecting the bobbins (17) already
formed and for delivering empty tubes (18) for the formation of new bobbins, this
operation being referred to as doffing change.
[0051] In a normal functioning of the machine shown in Figures 7a and 7b, the empty tubes
(18) will be assembled in alternating positions on a bobbin holder chain (20) assembled
with the possibility of shifting with regard to the overhead conveyor (19).
[0052] To detect possible positioning errors of the empty tubes (18) and/or of the roving
bobbins (17) during the doffing change, the roving frame incorporates sensors (21)
which can be photoelectric cells arranged parallelly to the alignments of empty tubes
and bobbins.
[0053] In order for said sensors (21) to be able to detect the incorrect position of any
of the empty tubes (18) or the bobbins (17) during the doffing change, the bedplate
(1) describes alternating vertical movements and horizontal movements, such that the
empty tubes (18) or the bobbins (17) which are in an incorrect position are laterally
shifted or tilted, enabling their detection by the sensors (21).
[0054] Specifically, in Figures 8a and 8b, one of the empty tubes (18) placed incorrectly
on the chain (20) of the overhead conveyor can be observed.
[0055] By means of a first upward movement of the bedplate (1) and a subsequently transverse
shifting, the empty tube (18), assembled in an incorrect position in Figures 8a and
8b, is detected by one of the sensors (21), as shown in the enlarged detail of Figure
8a, said sensor (21) causing the shutdown of the roving frame.
[0056] In Figures 9a and 9b, a bobbin (17) which has not been correctly delivered to the
overhead conveyor and remains assembled on the bedplate (1) can be observed. By means
of the vertical and transverse shiftings of the bedplate (1), said bobbin (17) is
arranged in a position in which it is detected by one of the sensors (21) which causes
the shutdown of the roving frame.
[0057] In Figures 10a and 10b, an error in transferring one of the empty tubes (18) to the
bedplate (1) is represented, said empty tube (18) remaining assembled on the conveyor
(19). As in the previous cases, the horizontal and vertical shiftings of the bedplate
cause the arrangement of said empty tube (18) in a tilted position, in which it is
detected by the sensor (21), said sensor causing the shutdown of the machine so that
the operator can position the empty tube (18) in the correct position.
[0058] Once the full bobbins are transferred to the overhead conveyor (19) and the empty
tubes (18) are positioned on the barbs (2) of the bedplate, as represented in Figure
11, said bedplate (1) is transversally shifted toward the front area of the machine
and is subsequently shifted vertically (Figure 13) to be arranged in the suitable
position for the formation of new roving bobbins on the empty tubes (18).
[0059] As can be observed in Figures 14, 15 and 16, the overhead conveyor (19) defines a
closed path for the shifting of the bobbin holder chain (20), the rails of said overhead
conveyor (19) having two notably parallel intermediate sections (22) linked at their
ends by means of a diverging oblique section (23) and two sections (24, 25) which
are symmetrical with regard to the vertex, in the manner of a circular segment.
[0060] This conveyor (19) has two motors (26, 27) for the alternate dragging of the branches
of the bobbin holder chain (20) which respectively circulate on the branches (22)
of the overhead conveyor (19).
[0061] Said bobbin holder chain (20) is formed by a series of hinge bars (21) whose length
is greater than the separation existing between the intermediate sections (22) of
the rails of the conveyor and notably equal to the radius of curvature of the curved
sections (24, 25) of the rails of said conveyor, such that during the actuation of
the motor (27), only one of the branches of the bobbin holder chain moves forward,
specifically the one represented in the lower position in Figure 15, whereas the upper
branch remains static and two of the hinge bars (21) pivot on one of their ends, the
opposite end of said bars (21) shifting over the curved section (24 and 25), respectively,
of the opposite ends of the conveyor.
[0062] As can be observed in Figure 16, when motor (26) acts, only the shifting of the upper
branch of the bobbin holder chain occurs, two end links (21) pivoting on one of their
ends and being shifted with the opposite end over the curved sections (25 and 24)
of the opposite ends of the conveyor (19).
[0063] As can be observed in Figures 17 and 18, the overhead conveyor (19) is suspended
from the bedplate (28) by means of several screw-nut assemblies (29) enabling the
vertical shifting of said conveyor (19) in the event that the latter receives an upward
push due, for example, to the incorrect positioning of one of the empty tubes (18)
during the doffing change. In the event that this vertical shifting of the conveyor
(19) occurs, as shown in Figure 18, the overhead conveyor will act on a sensor (30)
positioned over the bedplate and causing the automatic shutdown of the roving frame,
preventing the breaking of any of the members thereof.
[0064] The sensor (30) can optionally be assembled on the overhead conveyor (19), as shown
in Figure 19.
[0065] As previously discussed, this roving frame incorporates a cooling circuit, schematically
shown in Figure 20. Said cooling circuit uses the air coming from the pneumatic cleaning
circuit (31) belonging to the roving frame, using it to cool those parts of the roving
frame normally reaching a temperature exceeding that of the air coming from the pneumatic
cleaning circuit (31).
[0066] These pneumatic cleaning circuits (31) usually have an impurity collection tank (32),
the filtered air passing through a filter (33) due to the action of an exhaust ventilator
(34).
[0067] In the example shown in Figure 20, the cooling circuit object of the invention has
a main duct (35) connected to a filtered air outlet defined in the collection tank
(32). Said main duct (35) branches off, forming branches (36) provided with outlets
(37) projecting the air over those areas or parts of the machine to be cooled which,
specifically in said Figure 20, are represented by the motors (9, 15) and by the electrical
control panel (38) of the roving frame.
[0068] In Figures 21, 22 and 23, the pressure finger (39) used in this roving frame for
carrying out the guiding of the roving (40) during the formation of the bobbins, is
shown. The pressure finger (39) has a baffle (41) on its free end provided with a
hole (42) for the passage of the roving and with a rear opening (43) tangentially
accessing the upper area of said hole (42) from the rear area of the baffle. The hole
(42) and the rear opening (43) demarcate a fin (44) whose upper-front area is laterally
tilted, as can be observed in Figure 23, preventing the roving (40) from being able
to be involuntarily released form the hole (42) when the breaking of the roving occurs
once the bobbin is formed, as shown in Figure 21.
[0069] Having sufficiently described the nature of the invention, as well as a preferred
embodiment example, it is hereby stated for all pertinent intents and purposes that
the materials, shape, size and arrangement of the members described can be modified,
as long as this does not imply an alteration of the essential features of the invention
which are claimed below.
1. A roving frame for the formation and delivery of roving bobbins; of the type comprising
a plurality of roving supply devices for the formation of bobbins on tubes coupled
on barbs associated to a shiftable bedplate with the aid of rotating spider assemblies
and a pressure finger for the guiding of the rovings, said bedplate being shiftable
between a first end position in the roving bobbin formation area and a second end
position in which the doffing change or automatic replacement of tubes holding bobbins
with empty tubes is carried out;
characterized in that it comprises:
- a movable bedplate (1) made up of several bedplate sections (3) aligned horizontally
and provided on their ends with means (10, 11) for controlling the horizontal position
of the successive bedplate sections (3) during the lifting and downward movements
of said bedplate,
- means (29) for the suspended support and with the possibility of vertical shifting
of the overhead conveyor (19) responsible for carrying out the collection of the roving
bobbins (17) delivered by the movable bedplate (1) and the delivery of the empty tubes
(18) to said bedplate,
- sensors (30) for the detection of possible upward movements of the overhead conveyor
(19) during the upward movement of the bedplate (1) in the rear area of the roving
frame during the change of roving bobbins (17) and empty tubes (18),
- sensors (21) for automatically verifying the correct position of the roving bobbins
(17) and of the empty tubes (18) during the passage thereof from the bedplate (1)
to the overhead conveyor (19) and from the overhead conveyor (19) to the bedplate
(1), respectively.
2. A roving frame according to claim 1, characterized in that the means for controlling the horizontal alignment of the successive bedplate sections
(3) comprise fixed sensors (10) in one of said bedplate sections (3) and a fixed bar
(11) in the following bedplate section which selectively acts on one of the sensors
(10) when said successive bedplate sections (3) become misaligned and form a positive
or negative angle between one another.
3. A roving frame according to claim 2, characterized in that the sensors (10) associated to the different bedplate sections (3) are connected
to an emergency shutdown circuit incorporated in the electrical control panel (38)
of the roving frame.
4. A roving frame according to claims 1 and 2, characterized in that successive bedplate sections (3) are assembled on respective rotating nuts (4), linked
to one another by a series of flexible transmission members (8) driven by at least
one drive member (9).
5. A roving frame according to claim 4, characterized in that the flexible transmission members (8) are made up of belts and/or of chains linking
pairs of consecutive rotating nuts (4).
6. A roving frame according to claim 4, characterized in that the rotating nuts (4) are assembled on respective vertical spindles (5), unable to
rotate, fixed to lower carriages (6) assembled with the possibility of longitudinal
shifting on respective sets of transverse rails (7), and fixed to flexible dragging
means (12) causing the transverse shifting of the lower carriages (6).
7. A roving frame according to claim 6, characterized in that the flexible dragging means of the lower carriages comprise transverse chain sections
(12) fixed to opposite ends of the lower carriages (6) and linked with respective
main branches (13) which are notably parallel and longitudinally arranged in the front
and rear areas of the roving frame.
8. A roving frame according to claim 7, characterized in that the main branches (13) are linked, at least at one of their ends, by a chain section
(14) which is actuated by a drive member (15) and which causes, when rotating in either
direction, the shifting of the main branches (13) in opposite directions and the transverse
and simultaneous shifting of the lower carriages (6) toward the front area or toward
the rear area of the roving frame.
9. A roving frame according to claim 1, characterized in that it comprises a cooling circuit provided with a main air circulation duct (35) connected
to the pneumatic cleaning circuit (31) belonging to the roving frame, said main duct
(35) branching off into a series of branches (36) provided with outlets (37) projecting
the air coming from the pneumatic cleaning circuit (31) toward the members (9, 15,
38) or areas of the roving frame to be cooled.
10. A roving frame according to claim 9, characterized in that the main duct (35) of the cooling circuit is connected to a filtered air outlet defined
in the impurity collection tank (32) of the pneumatic cleaning circuit (31).
11. A roving frame according to claim 1, characterized in that the means for the suspended support of the overhead conveyor (19) comprise a series
of screw-nut assemblies (29) fixed to the bedplate (28) of the roving frame and which
pass through holes defined in the rails of the overhead conveyor (19), said rails
being supported on said screw-nut assemblies (29) and having the possibility of vertical
shifting with regard to said screw-nut assemblies (29).
12. A roving frame according to claim 11, characterized in that the rails of the overhead conveyor (19) define a closed path for the shifting of
a bobbin holder chain (20), said rails having two notably parallel intermediate sections
(22), linked at their ends by means of a divergent oblique section (23) and two sections
(24, 25) which are symmetrical with regard to the vertex, in the manner of a circular
segment.
13. A roving frame according to claim 12, characterized in that the bobbin holder chain (20) is formed by a series of hinge bars, the length of each
bar being greater than the separation existing between the intermediate and parallel
sections (22) of the rails of the overhead conveyor (19), and notably equal to the
radius of curvature of the symmetrical sections (24, 25), in the manner of circular
segment, defined at the opposite ends of the rails of said overhead conveyor.
14. A roving frame according to claim 1, characterized in that the sensors (30) for the detection of possible upward movements of the overhead conveyor
(19) are arranged between the rails of the overhead conveyor (19) and the area of
the bedplate (28) carrying out the upper securing of said rails by means of the nut-screw
assemblies (29).
15. A roving frame according to claim 14, characterized in that the sensors (30) are connected to an emergency shutdown circuit incorporated in the
electrical control panel (38) of the roving frame.
16. A roving frame according to claim 1, characterized in that the sensors (21) responsible for automatically verifying the correct position of
the roving bobbins (17) and of the empty tubes (18) during the passage thereof from
the bedplate (1) to the overhead conveyor (19) and from the overhead conveyor (19)
to the bedplate (1), respectively, are made up of photoelectric cells arranged at
the opposite ends of the machine and slightly deviated with regard to the alignments
formed by the empty tubes (18) and the bobbins (17) in the collection and delivery
positions, to detect possible lateral deviations or tilting of those rovings or bobbins
(17) or empty tubes (18) incorrectly positioned on the overhead conveyor (19) or on
the bedplate (1) during the doffing change.
17. A roving frame according to claim 16, characterized in that the sensors (21) are connected to an emergency shutdown circuit incorporated in the
electrical control panel (38) of the roving frame.
18. A roving frame according to claims 1, 16 or 17, characterized in that in the doffing change end position, the bedplate (1) alternately defines upward or
downward vertical movements and forward and backward horizontal movements, those bobbins
(17) and/or empty tubes (18) which are in an incorrect position deviating or tilting
in the horizontal movements toward a position in which they are detected by the sensors
(21) responsible for verifying the correct position of the bobbins (17) and of the
empty tubes (18).
19. A roving frame according to claim 1, characterized in that the guiding of each one of the rovings (40) during the formation of bobbins (17)
is carried out by means of a pressure finger (39) having a baffle (41) in the area
resting on the bobbin (17) which is provided with a hole (42) for the passage of the
roving and with a rear opening (43) tangentially accessing the upper area of said
hole (42); said rear opening (43), together with the hole (42), demarcating a retention
fin (44) for retaining the roving (40) inside said hole (42).
20. A roving frame according to claim 19, characterized in that the retention fin (44) has a lateral tilt in its front-upper area, slightly projecting
toward the outer side of the baffle (41).