|
(11) | EP 0 098 255 A2 |
| (12) | EUROPEAN PATENT APPLICATION |
|
|
|
|
|||||||||||||||||||||||||||
| (54) | A weft reservoir for fluid jet looms |
| (57) In construction of a pin control type weft reservoir particularly suited for alternate
weaving by two sorts of wefts on fluid jet looms, coils of weft for two successive
weft insertions are fairly separately reserved and independently delivered on a reservoir
drum concurrently and compatiblly with continuous supply of weft by a yarn guide through
cooperation of three control pins arranged one another in the axial direction of the
reservoir drum which enable two separate inter-pin weft assignment to a common control
pin by their phased movement in the radial direction of the reservoir drum. |
Background of the invention
[0001] The present invention relates to a weft reservoir for fluid jet looms, and more particularly relates to improvement in construction and operation of a weft reservoir in particular suited for alternate weaving by two sorts of wefts on a fluid jet loom on which weft is wound about a reservoir drum made up of conical and cylindrical sections by operation of a rotary yarn guide synchronized with loom running, and reserved thereon and delivered therefrom for insertion of weft under proper pin control.
[0002] In the following description, the side of arrangement closer to the supply source of weft will be referred in general to as "the upstream side" whereas the side closer to the main jet nozzle is referred in general to as "the downstream side".
[0003] Insertion of weft on a loom in general starts at a moment between 90 and 110° crank angle and terminates at a moment between 250 and 270° crank angle. First, the weft is unwound from the reservoir drum in the mode of free delivery and the so-called controlled delivery of the weft starts just before the end of the insertion of weft. For simplification purposes, however, it is assumed now that insertion of weft should start at about 90 crank angle and terminate at about 270" crank angle.
[0004] When a control pin is located within its operative zone, the control pin is able to come into engagement with a weft on the reservoir drum and hinder its delivery from the reservoir drum. When a control pin is located in its stand-by zone, the control pin stays out of engagement with a weft on the reservoir drum and allows delivery of the weft from the reservoir drum. More specifically, a control pin is first registered at the most advanced position in the operative zone during its operation. Then the control pin recedes from the most advanced position, leaves the operative zone while concurrently intruding into the stand-by position, and is finally registered at the most receded position in the stand-by zone. On return route, the control pin advances from the most receded position in the stand-by position, leaves the stand-by zone while concurrently intruding bock into the operative zone, and is again registered at the most advanced position in the operative zone for the next operation.
[0005] In the case of a weft reservoir on which ancontrol pin or pins are arranged outside a reservoir drum, the control pin or pins leave the operative zone by moving radially away from the outer periphery of the reservoir drum to such an extent as to stay out of any engagement with the weft on the reservoir drum, and intrude into the operative zone by moving radially towards the outer periphery of the reservoir drum to such an extent as to come into engagement with the weft on the reservoir drum.
[0006] On a weft reservoir used for alternate weaving by two sorts of wefts, coils of weft for two successive insertion of weft have to be reserved on a reservoir drum in a fairly separated state, and delivered independently at the respective moments of weft insertion. Such reservation and delivery of weft have to be carried out concurrently and compatibly with continuous supply of weft from the source of supply by the rotary yarn guide.
Summary of the invention
[0007] It is the basic object of the present invention to enable fairly separated reservation and independent delivery of weft for two successive insertion of weft on a weft reservoir concurrently and compatibly with continuous supply of weft by a rotary yarn guide.
[0008] In accordance with the basic aspect of the present inven-i tion , three sets of cam driven control pins are arranged one after another in the axial direction of a reservoir drum each for timed movement along a substantially straight path of travel in the radial direction of the reservoir drum between operative and stand-by zones.
Brief description of the drawings.
[0009]
Fig.l is a side view, partly in section, of one embodiment of the weft reservoir in accordance with the present invention,
Fig.2 is a plan view, partly in section, of the weft reservoir shown in Fig.l, and
Fig.3 shows operation of the weft reservoirs shown in Figs. 1 and 2.
Description of the preferred embodiments.
[0010] One embodiment of the weft reservoir in accordance with the present invention is shown in Figs.land2, in which a stationary reservoir drum is used. Needless to say, however, the present invention can well be applied to a weft reservoir provided with a rotary reservoir drum, too.
[0011] Although application of the weft reservoir is hereinafter explained in connection with alternate weaving by two sorts of wefts, the weft reservoir can well be used for weaving by one sort of weft, too.
[0012] Further, in the contruction of the following weft reservoir, three control pins are all arranged outside the reservoir drum so that they should move radially away from and towards the outer periphery of the reservoir drum. But, this arrangement may be reversed. That is, the three control pins may all be arranged inside the reservoir drum so:that they should appear on and disappear from the outer periphery of the reservoir drum. Further, some may be arranged outside and the other may be arranged inside the reservoir drum.
[0013] In the drawings, elements of the weft reservoir not directly related to the present invention are either omitted or simplified for easier understanding.
[0014] The weft reservoir includes a reservoir drum 1 made up of an upstream side conical section la and a downstream side cylindrical section lb and a slot 1C extending in the axial direction of the reservoir drum 1 is formed about the border berween the conical and cylindrical sections la and lb.
[0015] A magagine 10 is arranged on the outer side of and in a fixed relationship to the reservoir drum 1 and a slot 10a extending in the axial direction of the reservoir drum 1 is formed in the wall of the magagine 10 facing the reservoir drum 1. The slot 10a in the magagine 10 extends substantially in the area corresponding to the slot lc formed in the reservoir drum 1. Three sets of control pins P1 to P3 are directed towards the outer periphery of the reservoir drum 1 through the slot 10a in the magagine 10 and their drive cams Cl to C3 are encased within the magagine 10 as later described in more detail. A horizontal guide 15 is fixedly arranged within the magagine 10 through which the control pins P1 to P3 slidably extend for substantially straight movement. Compression springs 112, 122 and 132 are interposed between the upper surface of the guide 15 and enlarged heads of the control pins P1 to P3 in order to keep the points of the control pins P1 to P3 radially away from the outer periphery of the reservoir drum 1. In this way, the control pins P1 to P3 are resiliently kept in their stand-by zone unless any external force act on their enlarged heads.
[0016] A support shaft 14 is fixedly arranged in the magagine 10 whilst extending in a direction normal to the axial direction of the reservoir drum 1, and three sets of bifurcate levers 11 to 13 are idly inserted, in a juxtaposed relationship to each other, over the support shaft 14. A cam shaft 17 is also rotatably arranged in the magagine 10 in parallel to the support shaft 14, and operationally coupled to a proper source of drive such as the main drive shaft for the rotary yarn guide for rotation synchronized with loom running. Three sets of drive cams C1 to C2 are secured to the cam shaft 17 in a juxtaposed arrangement. In the drawing, only a part of the outline of the third drive cam C3 is illustrated for simplification purposes.
[0017] The first lever 11 on the support shaft 14 rotatably carries at its upstream end a roller 111 in sliding contact with the enlarged head of the first control pin P1, the second lever 12 rotatably carries at its upstream end a roller 121 in sliding contact with the enlarged head of the second control pin P2, and the third lever 13 rotatably carries at its upstream end a roller 131 in sliding contact with the enlarged head of the third control pin P3. As a substitute for the above-described roller VS. large head contace, each lever may be provided with a plain upstream end in combination with a roller rotatably coupled to the head of a corresponding control pin as long as a sort of sliding contact exists between the two mating elements for straight movement of the control pin.
[0018] The first lever 11 further.rotatably carries at its downstream end a cam follower 113 kept in resilient rolling contact with the first drive cam C1 by assistance of a tension spring (not shown) interposed between its body and a spring holder 16 secured to the magagine 10, the second lever 12 rotatably carries at its downstream end a cam follower 123 kept in resilient rolling contact with the second drive cam (2 by assistance of a tension spring (not shown) interposed between its body and the spring holder 16, and the third lever 13 rotatably carries at its downstream end a cam follower 133 kept in resilient rolling contact with the third drive cam C3 by assistance of a tension spring 134 interposed between its body and the spring holder 16.
[0019] When the compression springs 112 to 132 interposed between the top surface of the guide 15 and the enlarged heads of the control pins P1 to P3 are strong enough to keep the cam followers 113 to 133 in resilient contact with the drive cams C1 to C3, the tension springs attached to the bodies of the levers 11 to 13 may be omitted.
[0020] In operation, as the drive cams C1 to C3 rotate, the levers 11 to 13 swing about the support shaft 14 counterclockwise in Fig.1, respectively, in order to force the control pins P1 to P3 intrude into their operative zones against repulsion by the compression springs 112 to 113. As the drive cams C1 to C3 further rotate, the levers 11 to 13 swing about the support shaft 14 clockwise in Fig.1, respectively, in order to allow the control pins P1 to P3 recede from their operative zones by assistance of the springs 112 to 132.
[0021] One example of the operation of the weft reservoir in accordance with the present invention will hereinafter be explained in connection with a 2x 2 type alternate weaving by two sorts of wefts in which two wefts of the first sort and two wefts of the second sort are inserted alternately. That is, assuming that two sorts of wefts A and B are used, insertion of weft is carried out in the order of A, A, B, B, A,A, BB. To this end, two sets of weft reservoirs of substantially same function are used in combination. Each of the drive cams C1 to C2 completes its one cycle rotation within a period of 0 to 1440° crank angle, weft delivery for the first weft insertion is carried out within a period of 0 to 360° crank angle, and weft delivery for the second weft insertion is carried out within the period of 360 to 72bo crank angle on one weft reservoir. During the remaining period of 720 to 1440° crank angle, weft delivery for insertion of weft is carried out twice in succession on the other weft reservoir.
[0022] In Fig.3, four coils of weft are assumed to provide the length of weft necessary for one insertion of weft. Further in the illustration, black circles indicate coils of weft used for the first insertion of weft whereas white circles indicate coils of weft used for the second insertion of weft.
[0023] A moment I in Fig.3 corresponds to 90° crank angle. At this moment, the first and second control pins P1 and P2 stay standstill at the most advanced positions in their operative zones whereas the third control pin P3 has already started to recede from the most advanced position in its operative zone by moving radially outwards along a substantially straight path of travel. Coils of weft for the second insertion are kept between the first and second control pins P1 and P3 whereas coils of weft for the first insertion are on the verge of delivery on the downstream side of the second control pin P2.
[0024] A moment II in Fig.3 corresponds to 180° crank angle. At this moment, the first and second control pins P1 and P2 keep staying standstill at the most advanced position in their operative zones whereas the third control pin P3, as a result of its continued recession, has already reached the most receded position in its stand-by zone. The coils of weft for the second insertion are still kept between the first and second control pins P1 and P2 whereas the coils of weft on the downstream side of the second control pin P2 have been almost delivered and the first insertion of weft is going to terminate.
[0025] A moment III in Fig. 3 corresponds to 270' crank angle. At this moment, the first control pin P1 still remains at the most advanced position in its operative zone, the second control pin P2 has started to recede from the most advanced position in its operative zone, and the third control pin P3 has started to advance from the most receded position in its stand-by position. Reservation of weft for the first weft insertion of the next cycle has already started on the upstream side of the first control pin P1, the coils of weft for the second weft insertion are still held in the area between the first and second control pins P1 and P2, and weft delivery for the first insertion of weft has already terminated on the downstream side of the second control pin P2. In other words, the first insertion of weft has terminated at this moment.
[0026] A moment IV in Fig.3 corresponds to 360° crank angle. At this moment, the first control pin P1 is at the most advanced position in its operative zone, the second control pin P2 is now registered at the most receded position in its stand-by position, and the third control pin P3 has arrived at the most advanced position in its operative position. Reservation of weft continues on the upstream side of the first control pin P1 and the coils of weft, which have been held in the area between the first and second control pins P1 and P2, now automatically move to the area between the second and third control pins P2 and P3 due to difference in diameter between the conical and cylindrical sections 1a and lb of the reservoir drum 1. To this end, it is preferable that the first and second control pins P1 and P2 should be arranged in the axial direction of the reservoir drum 1 so that the area between them should at least partly include the conical section 1a of the reservoir drum 1. In this way, the coils of weft for the second weft insertion are assigned from the second to third control pin about this moment.
[0027] A moment V in Fig.3 corresponds to 450° crank angle. At this moment, the first control pin P1 remains at the most advanced position in its operative zone, the second control pin P2 rests at the most receded position in its stand-by position, and the third control pin P3 has started to recede from the most advanced position in its operative zone. Reservation of weft continues on the upstream side of the first control pin P1 and the coils of weft, which have been passed over to the third control pin P3, are now on the verge of delivery for the second insertion of weft.
[0028] A moment V1 in Fig.3 corresponds to 540° crank angle. At this moment, the first control pin P1 is registered at the most advanced position in its operative position whilst the second and third control pins P2 and P3 are registered at the most receded positions in their stand-by zones. Reservation of weft further develops on the upstream side of the first control pin P1, the coils of weft in the area between the second and third control pins P2 and P3 have been almost delivered, and the second insertion of weft is going to terminate.
[0029] A moment VEin Fig.3 corresponds to 630° crank angle. At this moment, the first control pin P1 has already started to recede from the most advanced position in its operative zone, the second control pin P2 stays standstill at the most receded position in its stand-by zone, and the third control pin P3 has started to advance from the most receded position in its stand-by zone. Reservation of weft further advances on the upstream side of the first control pin P1, the coils of weft in the area between the second and third control pins P2 and P3 have all been delivered, and the second insertion of weft has already terminated.
[0030] A moment VIII in Fig.3 corresponds to 720° crank angle. At this moment, the first and second control pins P1 and P2 are registered at the most receded positions in their operative zone and the third control pin P3 has already arrived at the most advanced position in its operative zone. Coils of weft, which have been held on the upstream side of the first control pin P1, now automatically move to the area between the second and third control pins P2 and P3 due to difference in diameter between the conical and cylindrical sections la and lb of the reservoir drum 1. To this end, it is perferable that at least the first control pin P1 should be located in the area of the conical section la of the reservoir drum 1. In this way, the coils of weft for the first weft insertion are assigned from the first to third control pin about this moment. This automatic assignment of weft should be compared with that about the moment 1V(=360° ) in coils of weft for the second weft insertion are assigned from the second to third control pin.
[0031] A moment 1X in Fig.3 corresponds to 810° crank angle. At this moment, the first control pin P1 is registered at the most receded position in its operative zone, the second control pin P2 has already reached the most advanced position in its operative zone, and the third control pin P3 stays standstill at the most advanced position in its operative-zone. Coils of weft for the first insertion of weft of the next cycle are held in the area between the second and third control pins P2 and P3. This state of holding will be maintained untill a moment XVI in Fig.3 which corresponds to 1440° crank cycle.
[0032] A moment X in Fig.3 corresponds to 900° crank angle. The first to third control pins P1 to P3 all maintain their positions at the preceding moment IX.
[0033] A moment XI in Fig.3 corresponds to 990 crank angle. The positions of the control pins P1 to P3 are unchanged. Reservatiion of weft for the second weft insertion of the next cycle has already started on the upstream side of the second control pin P2.
[0034] Moments XII and XIII correspond to 1080 and 1170 crank angles. The positions of the control pins P1 to P3 are unchanged, and the reservation of weft for the second weft insertion of the next cycle continues on the upstream side of the second control pin P2.
[0035] Moments XIV, XV and XVI in Fig.3 correspond to 1260, 1350 and 1440° crank angles, respectively. The positions of the control pins P1 to P3 are unchanged, and the reservation of weft for the second weft insertion of the next cycle further develops on the upstream side of the second control pin P2.
[0036] During the period between the moments XII and XVI, two times of weft insertions are carried out in succession on the other set of weft reservoir.
[0037] The operations of the three control pins P1 to P3 during the period between the moments I to XVI in Fig.3 are summerized as shown in the following table, in which the black circle indicates the weft for the first weft insertion and white circles indicates that for the second.
Operation of the control pins
[0039] As is clear from this table, the first control pin P1 is mainly involved in reservation of the weft for the first weft insertion, the second control pin P1 is mainly involved in reservation of weft for the second weft insertion, and the third control pin P3 controls delivery of weft for the first and second weft reservations. The coils of weft for the first weft insertion are assigned from the first to third control pin and the coils of weft for the second weft insertion are assigned from the second to third control pin at different moment.
[0040] As is clear from the foregoing, coils of weft for different weft insertions are fairly separately reserved and independently subjected to delivery through phased instruction into and recession out of the operative zones by three sets of control pins arranged one after another in the axial direction of a reservoir drum.
[0041] In the case of the embodiment shown in Figs. 1 and 2, a slide contact is provided between the head of each control pin and the upstream end of an associated lever so that the control pin should be driven for a movement in the radial direction of the reservoir drum along a substantially straight path of travel by assistance of the fixed guide 15. When the distance between the upstream and of the lever and the support shaft 14 is taken sufficiently larger than the length of the path of travel of the associated control pin, the head of the control pin may be directly pivoted to the upstream end of the associated lever, thereby assuring an approximately straight path of travel for the control pin.
1. A weft reservoir for fluid jet looms on which weft is reserved and delivered under
pin control comprising
a reservoir drum made up of an upstream side conical section and a downstream side cylindrical section,
a yarn guide rotatable about said reservoir drum for continuous supply of weft taken from a given source of supply,
three control pins annexed to said reservoir drum one after another in the axial direction of said reservoir drum with their points being directed to respective operative zones taken on the outer periphery of said reservoir drum, and
means for driving each of said control.pins for movement in the radial direction of said reservoir drum along a substantially straight path of travel between said operative position and a stand-by position in such a manner that, during said movement, coils of weft for different insertion of weft should be separately assigned to the most downstream control pin from other control pins at different moments.
2. A weft reservoir as claimed in claim 1 in which
at least the operative zone of the most upstream control pin is at least partly located in the area of said conical section of said reservoir drum.
at least the operative zone of the most upstream control pin is at least partly located in the area of said conical section of said reservoir drum.
3. A weft reservoir as claimed in claim 2 in which
said most upstream control pin is involved in reservation of weft for the first weft insertion in one cycle of operation,
said most downstream control pin is involved in control of weft delivery from said reservoir drum, and
an intermediate control pin is involved in reservation of weft for the second weft insertion in said one cycle of operation.
4. A weft reservoir as claimed in claim 1 in which
at least one of said stand-by zones for said control pins is taken radially outside said reservoir drum.
at least one of said stand-by zones for said control pins is taken radially outside said reservoir drum.
5. A weft reservoir as claimed in claim 1 in which
at least one of said stand-by zones for said control pins is taked radially inside said reservoir drum.
at least one of said stand-by zones for said control pins is taked radially inside said reservoir drum.
6. A weft reservoir drum as claimed in claim 1, 4 or 5 in which
said driving means includes a cam drive mechanism synchronized with loom running.
said driving means includes a cam drive mechanism synchronized with loom running.
7. A weft reservoir as claimed in claim 6 in which said cam drive mechanism includes
a framework arranged in fixed relationship to said reservoir drum,
a support shaft secured to said framework,
a cam shaft rotatably mounted to said framework and synchronized in rotation with said loom running,
three drive cams secured to said cam shaft, and
three swing levers pivoted to said support shaft each operationally coupled at one end to one of said drive comes and at the other end to one of said swing levers.