CA1146046A - Selectively timed combined warp and weft loom stop motion - Google Patents
Selectively timed combined warp and weft loom stop motionInfo
- Publication number
- CA1146046A CA1146046A CA000375501A CA375501A CA1146046A CA 1146046 A CA1146046 A CA 1146046A CA 000375501 A CA000375501 A CA 000375501A CA 375501 A CA375501 A CA 375501A CA 1146046 A CA1146046 A CA 1146046A
- Authority
- CA
- Canada
- Prior art keywords
- loom
- cycle
- stop motion
- weft
- warp
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
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Classifications
-
- D—TEXTILES; PAPER
- D03—WEAVING
- D03D—WOVEN FABRICS; METHODS OF WEAVING; LOOMS
- D03D51/00—Driving, starting, or stopping arrangements; Automatic stop motions
- D03D51/06—Driving, starting, or stopping arrangements; Automatic stop motions using particular methods of stopping
- D03D51/08—Driving, starting, or stopping arrangements; Automatic stop motions using particular methods of stopping stopping at definite point in weaving cycle, or moving to such point after stopping
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- Engineering & Computer Science (AREA)
- Textile Engineering (AREA)
- Looms (AREA)
Abstract
Title of the Invention SELECTIVELY TIMED COMBINED WARP AND WEFT LOOM
STOP MOTION
Abstract of the Disclosure A combined warp and weft loom stop motion which is effective to bring the loom to a halt at different points along the loom cycle according to the type of yarn that has broken. Each of a pair of separate driving means is driven in predetermined adjustable timed relation to the loom operating cycle and is connected to the loom drive operating control only when the corresponding yarn breaks. Preferably, the stop motion in-cludes a loom control circuit operable to weave a single weft yarn and then stop the loom at a generally predetermined point in order to facilitate repair of a defective cycle.
STOP MOTION
Abstract of the Disclosure A combined warp and weft loom stop motion which is effective to bring the loom to a halt at different points along the loom cycle according to the type of yarn that has broken. Each of a pair of separate driving means is driven in predetermined adjustable timed relation to the loom operating cycle and is connected to the loom drive operating control only when the corresponding yarn breaks. Preferably, the stop motion in-cludes a loom control circuit operable to weave a single weft yarn and then stop the loom at a generally predetermined point in order to facilitate repair of a defective cycle.
Description
1146~46 Field of the Invention This invention relates to the field of loom stop moSions and is con-cerned more particularly with a combined warp and weft loom stop motion which can be selectively timed 80 as to ha~t the loom in the event of yarn breakage at different point~ in its operating cycle dependent upon whether the breakage is of a weft or warp yarn, the stopping points being selected to facilitate repair of the particular breakage.
Background of the Invention Looms for weaving cloth have for many years been conventionally equipped with stop motions for detecting breakage or other loss of tension in any of the warp threads as well as the breakage or failure for other reasons to in~ert a filling thread into the ~hed of the loom defined between opposed groups of warp threads. While the~e stop motions can take variou~ forms, they are usually designed to close electrical contacts when any warp or filling thread breaks and thereby emit a control signal which is utilized to stop or "knock-off" the mechanical drive of the loor.
Ideally, warp and filling breakages have different requirements as regards the point in the operative cycle of the loom at which the breakage or other defect causing the stoppage can be repaired. The warp threads, of course, pass through the eyeY of the heddles, which are shifted up and down to separate the groups of warp threads and form the weaving shed, and since any broken warp thread must be rethreaded through its corres-ponding heddle eye, it obviously will be easier to accomplish such re-threading whcn the heddles are in or near their closed position, and their 2S eyes are ~ubstantially aligned with the median plane o the warp, rather than when the heddles are open or separated and the warp threads are stretched apart. Thus, the optimum stopping position for repairing a 28 warp thread breakage is with the lay of the loom approaching front dead
Background of the Invention Looms for weaving cloth have for many years been conventionally equipped with stop motions for detecting breakage or other loss of tension in any of the warp threads as well as the breakage or failure for other reasons to in~ert a filling thread into the ~hed of the loom defined between opposed groups of warp threads. While the~e stop motions can take variou~ forms, they are usually designed to close electrical contacts when any warp or filling thread breaks and thereby emit a control signal which is utilized to stop or "knock-off" the mechanical drive of the loor.
Ideally, warp and filling breakages have different requirements as regards the point in the operative cycle of the loom at which the breakage or other defect causing the stoppage can be repaired. The warp threads, of course, pass through the eyeY of the heddles, which are shifted up and down to separate the groups of warp threads and form the weaving shed, and since any broken warp thread must be rethreaded through its corres-ponding heddle eye, it obviously will be easier to accomplish such re-threading whcn the heddles are in or near their closed position, and their 2S eyes are ~ubstantially aligned with the median plane o the warp, rather than when the heddles are open or separated and the warp threads are stretched apart. Thus, the optimum stopping position for repairing a 28 warp thread breakage is with the lay of the loom approaching front dead
- 2~
11~6~46 center but not so close to be front dead center that the weft thread would be beaten up into the fabric, say at about 320 of the loom cycle starting from front dead center. ~
Contrariwise, the filling thread is inserted into the shed while the warp groups defining the shed are well separated apart and removal of a broken weft thread can most easily be carried out when the shed is reason-ably open. Once the shed begins to close, as the heddles move together, the warp threads begin to grip the incomplete weft thread which makes its removal much morè difficult. ~hus, the optimum position of the loom for purposes of repair of a filling defect iswhen the lay of the loom is adjacent to back dead center.
The stopping position of the loom, particularly in case of warp break-age, mu~t also take into account the avoidance of so-called "8et-marks"
in the woven fabric. If the lay of the loom is allowed to stop too near front lS dead center and the loom is again started at that point, the portion of the cycle remaining until front dead center is too short for the lay to build up to its normal operating speed and momentum and thus as the lay reaches front dead center, the reed carried thereby will impact against the last in-serted weft thread with a force less than normal. This difference in beat-up force will appear in the fabric and cause what is referred to as a "set-mark". Traditionally, the practice in the art has been for the loom attend-ant to rotate the crankshaft of the loom backwards by hand, using a large wheel provided at one end of the crankshaft for this purpose, so as to re-locate the lay and other operative components at a starting position effective to avoid the set-mark problem.
In addition, there exist certain circumstances under which it bccomes desirable to have the loom insert a single pick and then be brought to a 28 halt. Single-pick operation i8 useful, for example, in facilitating the ~1~6~6 repair of a defective pick in automatically positioning the loom on signal in position to enable the repair to be corrected with a minimum of difficulty. In the past, "single-pick" operation has been carried out under-the control of the operator, who if need be rolls back the loom crankshaft to the appropriate starting position and then operates the loom to insert a single pick or weft by direct manipulation of the loom operating handle.
Objects of the Invention A principal object of the present invention is the provision of a simplified combined loom stop motion which is responsive to both warp and filling breakages and is capable in the event of either such breakage of auto-matically bringing the loom to a halt in a condition optimally suited to the correction of the particular breakage.
A further object of the invention is a combined warp and weft stop motion which is selectively adjustable to cause stoppage of the loom in different positions according to the type of defect which occurs.
Another object of the invention is a provision of a loom stop motion which can be utilized for achieving automatic single pick operation.
Brief DPscription of the Drawings These and other objects of the invention will be more fully revealed by the following description of the accompanying drawing~ in which:
Fig. 1 is a side elevation in somewhat diagrammatic form of one em-bodiment of the combined stop motion of the present invention in operative position, and Fig 2 is a plan view looking down substantially along line 2-2 of Fig. 1, Detailed Descriptlon of the Invention In Fi.g. 1, the combined stop motion of the present invention is seen 28 in side elevation in o?erative position mounted on the loom, with, however, _ ~ _ 1146~3~6 only those components of the loom which are directly associated with the invention; namely, the crankshaft and operating handle, being shown as is nece3sary for following thi~ description. In Fig. 1, a pair of control solenoid housings 10, 10' are mounted on a bracket 12 which iB fixed to a convenient stationary part of the loom (not shown). One of these solenoids 10 is wired to receive the control si~nals fro;n a weft or filling breakage detecting means while the other 10' is wired to receive the control signals fron~ a warp breakage detector means, neither detecting means being shown. The construction and operation of these detecting means have no significant bearing on either the structure or operation of the present in-vention and they can, accordingly, be of any of the conventional detection systems used for this purpose, the only requirement being that théy initiaie and deliver separate control pulses when a weft or a warp breakage, respectively, occurs. Each of the stop solenoids 10, 10' has its armature (not seen) connected to an exteriorly projecting operating lever 14, 14' so that upon energization of either solenoid 10, 10', the corresponding opera-ting lever i6 rocked upwardly and remains so until the solenoid is de-energized to return the lever to its starting position.
At its free end, each of operating levers 14, 14' has a connecting wire 16, 16' pivoted thereto which extend generally vertically downwardly in more or less parallel relation to a common '~nock-off" head 18. Since the distance between the points of connections of the lower ends of wires 16, 16' may vary in practice, preferably each connecting wire includes a serpentine section, as at 20, 20' which can be easily bent to make the rods 2S longer or shorter as circumstances may dictate.
Mounted at the left-hand end of the common "knock-off" head 18 for limited pivotal movement relative thereto between a generally horizontal 28 position and an upwardly tilted position (shown in dotted lines) are a p~ir 114~6~6 of knock-off ingers 22, 22' which are dispc>sed in spaced parallel relation to one another in the dimension perpendieular to the plane o Fig. 1, as is evident in the plan view of Fig. 2 . The shape of fingers 22, 22' is not of particular importance, the only requirements being that they have adequate strength to withstand substantial mechanical impact applied against their extreme outward ends. To this end, the fingers, as seen in the drawings, can be given a roughly dish-shape, with one side edge extending nange-like vertically as at 23, 23' for improved resistance to bending in bo,h planes. The flange edges 23, 23' can serve as a convenient p~int for en-gagement with the lower ends of wires 16, 16', each such edge being per-forated for engagement with hooks bent for that purpose in the lower wire ents, A supporting stub shaft Z6 i8 affixed to a pair of the loosn frame (not shown) and on shaft 26 are pivoted a pair of identical rocker arms 28, 28' extending generally vertically upwardly from the axis of shaft 26 in axially spaced apart relation, again best seen in Fig. 2. At their upper ends, each rocker arm 28, 28' carries a follower roller 30, 30' thereon and intermediate their ends, each arm carries a rightwardly projecting hammer 30, 30'. The axes of the hammers and knock-off fingers are so related that they lie in pairs, one hammer and one finger, in generally common planes in one direction (the vertical direction, as appears in Fig.
- 2). In the other direction ~i. e., as shown) axes of the respective pairs of hammers and fingers are offset or separated so as to be out of regis-tration when the knock-off fingers are actuated in the solid line position seen in Fig. 1 but are in registration when the fingers are situated in the dotted line upwardly displaced position. The front ends of the hammers are preferably notched or otherwise contoured for non-slipping engage-28 ment with the ends of fingers 22 22'.
1146~346 Each of the follower rollers 32, 32' rides on the peripheral ~urface of a corresponding cam 34, 34' mounted in axially spaced relation on the crankshaft of the loom 36 for rotation therewith. The cams 34, 34' are identically contoured so as to each provide a high region or lobe 38, 38' at one point thereon which is preceded by a ramp 40, 40' and followed by a gradually tapering transition 42, 42' which merges into a low region 44, 44' equal to about 180 of the cam periphery. While the cam contours are preferably the same, they are arranged in out of phase relationship on the loom crankshaft so that the respective lobes thereof move into contact with the corresponding follower rollers at different points on the loom cycle.
The rocker arms are biased into contact with the cam peripheries, as by springæ 45, 45' and the starting positions of the cams on the crankshaft can be adju6ted individually by means of set screws or the like (not shown).
In general, the geometry of the cams in relation to the followers, rocker arms and knock-off hammers is such as to cause each rocker arm and associated hammer to pivot between a retracted position spaced away from, i. e. leftwardly in Fig. 1, the extreme tip of its associated knock-off finger when the follower roller rides on the low section 44, 44' of the cam, and a projected operative position in which the knock-off harr~ner overlies its corresponding knock-off finger, as the latter is in full line position, when the follower roller makes contact with the high portion or lobe 38, 38' of the cam.
The knock-off head 18 is supported for horizontal reciprocating movement on a guide bracket 46 which is fixed on stub shaft which termi-nates at its upper end at a more or less frusto-conical shaped guide tongue 48 of reduced thickness so as to project through a vertical slot passing through at least the mid-section of thc knock-off head 18. The knock-off 28 head can, for example, be constructed of two matching side sections 47, ~46~46 47! united in 3paced apart relation so as to define a vertical slot 49 ~Fig.
Z) for penetration by tongue 48, each such qide qection carrying its own rigid knock-off finger. Below tongue 48, bracket 46 has increased thick-n¢~s, thereby forming opposed shoulders 52 (only one of which is visible in the drawing) and knock-off head 18 is thus supported for horizontal recipro-cating movement on bracket 46 generally horizontally along a path fixed by tongue 48. A tension spring 54 stretches between tongue 48 and head 18 to bias the latter toward the let in Fig. 1.
The end of knock-off head 18 opposite to fingers 22, 22' is affixed to the end of a rigid knock-off rod 56 which at its opposite end is pivoted to thè control handle 59, usually referred to as the "shipper" handle 59, of the loom, the connective arrangement being such that the solid line pc!sition of the knock-off head corresponds to the "on" or operating position of the operating handle. In this particular case shown, the shipper handle 59 occupies "on" position when pivoted clockwise and "off" position when swung counterclockwise, and the pivot axis of the handle itself, therefore, lies above the point of pivotal connection of the knocX-off rod 56 thereto.
The arrangement just described operates in the following manner:
While the loom is operating normally, the actuating levers 14, 14' of the respective stop solenoids 10, 10' remain in depressed position so that knock-off head 18 likewise occupies a depressed normal operating position - ~hown in solid lines in Fig. 1. As the crankshaft 36 rotates, each of the cams 34, 34' turns 360 during each weaving cycle and cause3 each of the rocker arms 28, 28' to oscillate back and forth in timed relation to such rotation. The hammers 30, 30' thus are consequently displaced to and fro in relation to the corresponding knock-off fingers, but as long as the knock-off head remain~ depressed or disabled, hammers 30, 30' pass 28 freely above the upper limits of iingers 22, 22' without contactina the 1146~46 same, and ;he weaving continues without interruption. When, however, either a wet or warp yarn breaks, the control signal generated by the corresponding conventional breakage detecting means i8 applied to the corresponding stop solenoid which actuates its armature to pivot the corres-ponding actuating lever upwardly. This lifts the corresponding lift rod 16, 16', thereby pivoting the knock-off fingers 22, 22' connected thereto up-wardly into the oscillating path of the associated hammer 30, 30'. Then, as the cam shaft continues to turn, the rocker arms will be rocked in their turn toward the corresponding knock-off finger so as to impact against such finger in its upwardly displaced position, creating a mechanical im-pul~e which is transmitted to knock-off head 18 and through rod 56 to the loom shipper handle driving it to its "off" position, causing the loom to ~top.
Since each of cam9 34, 34' corresponds in function to a particular type of defect, either warp breakage or weft breakage, and since the relative positions of the cams on the cranlcshaft can be adjusted, it becomes possible to control the timing of the knock-off action selectively to match the needs of the particular kind of defect. Such adjustment will naturally have to be made on a loom by loom basis; the driving mechanism of each different type of commercial loom has its own peculiar braking time con-stant and the effect of inertia will to some extent be different for each given loom but by observing the inertia and the braking time constant of a specific loom, the respective cams 34, 34' can, by trial and error, be arranged on crankshaft 36 so that they result in the loom coming to a halt at the proper points in its operating cycle for the defects in guestion. In the course of repairing a defect, the defect sensing means will be returned to its normal operating position, and the respective stop solenoids are re-28 set to their operating position, thereby returning the knock-off head to its _ 9 _ - ~1461346 depressed or disabled normal operating position before the shipper handle i8 pivoted to restart the loom. lt should be stated that the peripheral dis-placement of cams 34, 34' seen in Fig. 1 is selected primarily to distin-gui~h between the two cams and is not intended to represent actual illus-trative operating positions thereof which would in any case have to be tailored to the particular loom, as already stated.
It can be added, howe~er, that in general~ the optimum stopping point for purposes of repair of a filling defect is at approximately 200-210 of the cycle, while for a warp defect, the best stopping position is around 320 of rotation, keeping in mind in the latter case the need for the lay to be sufficiently remo~red from front dead center as to minimize the chance of a set-mark.
The combined stop motion of the present invention is also ideally adapted for utilization in fùrnishing the loom with the capability for single-pick operation, i. e. the insertion of a single weft and then coming auto-~natically to a halt. To this end, one of the stop solenoids 10, 10', prefer-ably the weft solenoid 10 for reasons to be explained shortly, is connected through a flip-flop 60 and a manual pushbutton switch 62 to a source o control current 64. When pushbutton 62 is closed either just before or simultaneously with mo~rement of the shipper handle 59 to "on~ position, flip-flop 60 is activated so as to actuate the stop solenoid 10 which causes the knock-off head 18 to be lifted to an enabling position with one of its knock-of fingers in position to be engaged by a knock-off hammer during the immediately following cycle of the loom. The flip-flop 60 can be re-set in any convenient way and, for sake of illustration, the extreme lower end of the shipper handle is provided with a magnetic tip 66 which is adapted to cooperate with a magnetically attractable switch 68, such as a 28 Hall effect switch, situated adjacent the path of the shipper handle end when ~l146~6 the latter is in its full "off" position. Thus, when the stop motion functions to knoclc off the loom due to actuation of ~he stop solenoid, the moven~ent of the shipper handle to its off position automatically resets flip-flop 60 in readiness for the next cycle.
Given the fact that the loom stops fairly late in its cycle in the event of the occurrence of a defective pick or warp breakage, stoppage of the loom within the same cycle wherein the defect occurs would impose enormous stress on the loom components and, consequently, it is in-tended in the practice of the present invention for the inertia of the loom 10 ' to carry its operating components, especially the lay, well into the sub-- sequent cycle, stopping at one of the predetermined points therealong as ~pecified above. This means, of course, that when a filling defect has occurred, the defective pick has already been beat up into the fabric and the heddlés have shifted position for the insertion of the following pick which has already been inserted across the open shed. In order to repair the defect pursuant to this invention, the inserted weft for the next cycle i8 removed by hand, the loom having been brought to a stop in po~ition appropriate for such removal. Next, the heddles must be returned to the position occupied by them when the defective pick was inserted and the single pick operation feature of the present invention enables this to be done by mere actuation of the single pick control by the loom attendant.
The heddles are thereby reversed, open~ng the shed to enable the defect-ive pick to be removed without interference. In the meantime~ a fresh pick has been inserted into the shed opened by reversal of the heddles and the lay has been positioned ready to resume the normal weaving operation.
In order to minimize the opportunity for set-marks to be created when the loom is restarted, it is preferred that the weft stop solenoid be integrated 28 into the single pick operation, receiving the control signal from the . _ _ . . _.. _ . _ . ___ , . . , ... , .. . . .. _ . . " .. " .........
~146(346 flip-Ilop 60 and thereby stopping the loom in the vicinity of 200-220 of its cycle, which i8 ideal for eliminating set-marks.
.A further consideration involved in the selection of the stopping point of the loom ollowing single-pick operation as well as or a wet de-fect, i8 the effect of the stopping point on the manipulation o the weft it-~el. While the system o the present invention can be employed quite successfully with conventional comn~ercial looms of all types, it is also especially useful in association with a loom of the fluid insertion type, and while various different looms operating in this way have been or are being designed, and all can in principle utilize the system of the invention with good results, a particular preferred fluid weft insertion loom is disclosed and claimed in application Serial No. 356,160 filed in the name of Charles W. Brouwer et al on July 15~ 1980 and commonly assigned herewith, to the tescription of which reference may be had for a fuller understanding of its operation. In the loom of application Serial No. 356,160, air or other inert compressible medium is delivered under predetermined pressure to the throat of an insertion noz~le and an important feature of that loom is tbe manner in which the flow of air to the nozzle is controlled to limit the duration of the air flow in the manner of a pul~e, the pressure of the air in this pulse being sufficiently high that this pulse contains all of the energynecessary to transport a typical yarn across the width of a typical commer-cial loom, say at least about 48". Because of this high air pressure, the weft yarn passing through the nozzle throat for insertion thereby into the warp i8 subjected to very substantial stress, particularly since the pre-ferred nozzle of the above-identified application is designed to impart supersonic ~relocities to the air flow downstream of it~ throat and the yarn i8 exposed to such high velocities.
28 It has been found that if the yarn i~ exposed to such intense air flow ~ 12 -~146~46 when it i8 being re~trained against movement, either before or after its insertioD into the loom shed, the stress upon the stationary yarn will be deleterious to that yarn. For this reason, th0 stopping point of the loom must be coordinated with the timing of the pulse or other ilow of the wet insertion medium 60 as to avoid stopping the loom, while the pulse control device remains substantially operative. Damage to the yarn is minimized, however, if the earliest stopping point of the loom is subsequent to termi-nation of the pulse of weft inserting medium; although in practice, some overlap is permissible provided the pulse is in its terminal phase at that point and is already undergoing a loss in pressure on the way towards imminent shutdown.
There i8 another advantage of the system of the invention which is of significant merit in actual commercial practice. The stopping positions of the heddles of the loom, which typically project in their open or spread position vertically well above the body of the loom and thus are readily visible at some distance, are different with the two kinds of defects in question, the heddles stopping in closed or together position for a warp de-fect and in well separated or open condition for a weft defect. Hence, simply by observing the position of the heddles, the operator is immedi-ately informed as to the kind of defect which requires attention and may, therefore, organize the approach to be taken for repair to minimize wasted time and effort.
The location of the present stop motion on the loom frame is ob-viously subject to some variation. As mentioned above, the driving cams are preferably mounted directly on the loom crankshaft, which might in-fluence its location, but this is not essential because the cam~ could be mounted elsewhere and driven in synchronism with the crankshaft by ~neans 28 of intermediate gearing, a timing belt coupling or the like. One useful 1~6~6 location i~ adjacent the inside of the side frame member neare6t the 6hipper handle ~which i8 UBUally actuated at front corner but well clear of the path~ of movement of operating components, such as the heddles and lay) to avoid interference therewith. The in~tant sg~tem ob~riously takeR
up relatively little space ~ince the axial thickness of its individual elements,and therefore the overall axial thicknes6, need only be such as to achieve the required mechanical strength and durability for long term ~peration.
From the foregoing it will be seen that the pre~ent invention pro--~naes unique and ad~rantageous method and apparatus for stopping a loom upon detection of a warp or filling defect with the variou~ mechanisms of the loom, particularly the lay and harnesses, in the optimum position for correction of a warp or filling defect. In practice with the prior art the repair of filling defect~ i8 a laborious and time-consuming task. For ex-mple, in effecting such repairfi on conventional ny shuttle looms it has been nece~ary, once the loom is ~topped, for the loom attendant to rotate the loom crardc~haft baclcward~ manually to relocate the lay and other operative loom component~ at a desired starting position to avoid the ~et-~rk problem. Next, the operator is required to remove the faulty pick.
Thereafter, the operator grasps and holds the filling end from the bobbin in the ~huttle with one hand while manually propelling the shuttle through the ~hed to insert a "good" pick in the shed for beat-up.
- In clear contradistinction to the foregoing, the present invention operates upon the detection of a faulty pick to ~top the loom automatically on the next cycle after the faulty pick has been beat into the fabric. This ~topping, ae previou~ly mentioned, occur~ when the loom is approximately 270 into the next cycle. When the loom is thus stopped the operator manually removes the pick then resident in the shed as fully explained in 28 prior cited patent application Serial No. 3~6,160. At this point, ~; \ ~ ~ 14 -~6~6 since the heddles mu$lt be reurned to the pOSitiOI-S they were in when the faulty pic~c was inserted into the fabric, that i6, the heddles must be re-versed to permit ready removal of the faulty pick. This is achieved by actuating pushbutton 62 which automatically operates the loom through one cycle with the loom stopping at approximately the 200-220 position. In the course of this single pick operation of ihe loom the shed is reversed to permit easy manual removal of the faulty pick from the fabric while, at the same time, causing a fresh pick to be inserted into position in the shed.
Additionally, the loom mechanisms are optimally positioned to beat up the further pick once the loom is restarted with the lay impacting against the further pick under its full operating force to thereby preclude a set-mark in the fabric at the locus where the filling repair has been made. There-fore, filling repairs as just described can be effected some three or more time~ faster in practice with the present invention than is possible with prior art techniques while, at the same time, aYoiding undesirable set-mark6 in the woven fabric.
While a preferred embodiment of the invention has been described, with various preferred aspects being identified, it will be understood and appreciated that the invention is not intended to be limited in its scope to these preferences as other alternatives and options will be readily avail-able within the skill of the art and will be obviously suggested by what has been specifically described and illustrated. Therefore, the invention is not intended to be confined in its scope to any specific characteristics ex-cept where expressly required by the accompanying claims.
;~8 ~ 15 -
11~6~46 center but not so close to be front dead center that the weft thread would be beaten up into the fabric, say at about 320 of the loom cycle starting from front dead center. ~
Contrariwise, the filling thread is inserted into the shed while the warp groups defining the shed are well separated apart and removal of a broken weft thread can most easily be carried out when the shed is reason-ably open. Once the shed begins to close, as the heddles move together, the warp threads begin to grip the incomplete weft thread which makes its removal much morè difficult. ~hus, the optimum position of the loom for purposes of repair of a filling defect iswhen the lay of the loom is adjacent to back dead center.
The stopping position of the loom, particularly in case of warp break-age, mu~t also take into account the avoidance of so-called "8et-marks"
in the woven fabric. If the lay of the loom is allowed to stop too near front lS dead center and the loom is again started at that point, the portion of the cycle remaining until front dead center is too short for the lay to build up to its normal operating speed and momentum and thus as the lay reaches front dead center, the reed carried thereby will impact against the last in-serted weft thread with a force less than normal. This difference in beat-up force will appear in the fabric and cause what is referred to as a "set-mark". Traditionally, the practice in the art has been for the loom attend-ant to rotate the crankshaft of the loom backwards by hand, using a large wheel provided at one end of the crankshaft for this purpose, so as to re-locate the lay and other operative components at a starting position effective to avoid the set-mark problem.
In addition, there exist certain circumstances under which it bccomes desirable to have the loom insert a single pick and then be brought to a 28 halt. Single-pick operation i8 useful, for example, in facilitating the ~1~6~6 repair of a defective pick in automatically positioning the loom on signal in position to enable the repair to be corrected with a minimum of difficulty. In the past, "single-pick" operation has been carried out under-the control of the operator, who if need be rolls back the loom crankshaft to the appropriate starting position and then operates the loom to insert a single pick or weft by direct manipulation of the loom operating handle.
Objects of the Invention A principal object of the present invention is the provision of a simplified combined loom stop motion which is responsive to both warp and filling breakages and is capable in the event of either such breakage of auto-matically bringing the loom to a halt in a condition optimally suited to the correction of the particular breakage.
A further object of the invention is a combined warp and weft stop motion which is selectively adjustable to cause stoppage of the loom in different positions according to the type of defect which occurs.
Another object of the invention is a provision of a loom stop motion which can be utilized for achieving automatic single pick operation.
Brief DPscription of the Drawings These and other objects of the invention will be more fully revealed by the following description of the accompanying drawing~ in which:
Fig. 1 is a side elevation in somewhat diagrammatic form of one em-bodiment of the combined stop motion of the present invention in operative position, and Fig 2 is a plan view looking down substantially along line 2-2 of Fig. 1, Detailed Descriptlon of the Invention In Fi.g. 1, the combined stop motion of the present invention is seen 28 in side elevation in o?erative position mounted on the loom, with, however, _ ~ _ 1146~3~6 only those components of the loom which are directly associated with the invention; namely, the crankshaft and operating handle, being shown as is nece3sary for following thi~ description. In Fig. 1, a pair of control solenoid housings 10, 10' are mounted on a bracket 12 which iB fixed to a convenient stationary part of the loom (not shown). One of these solenoids 10 is wired to receive the control si~nals fro;n a weft or filling breakage detecting means while the other 10' is wired to receive the control signals fron~ a warp breakage detector means, neither detecting means being shown. The construction and operation of these detecting means have no significant bearing on either the structure or operation of the present in-vention and they can, accordingly, be of any of the conventional detection systems used for this purpose, the only requirement being that théy initiaie and deliver separate control pulses when a weft or a warp breakage, respectively, occurs. Each of the stop solenoids 10, 10' has its armature (not seen) connected to an exteriorly projecting operating lever 14, 14' so that upon energization of either solenoid 10, 10', the corresponding opera-ting lever i6 rocked upwardly and remains so until the solenoid is de-energized to return the lever to its starting position.
At its free end, each of operating levers 14, 14' has a connecting wire 16, 16' pivoted thereto which extend generally vertically downwardly in more or less parallel relation to a common '~nock-off" head 18. Since the distance between the points of connections of the lower ends of wires 16, 16' may vary in practice, preferably each connecting wire includes a serpentine section, as at 20, 20' which can be easily bent to make the rods 2S longer or shorter as circumstances may dictate.
Mounted at the left-hand end of the common "knock-off" head 18 for limited pivotal movement relative thereto between a generally horizontal 28 position and an upwardly tilted position (shown in dotted lines) are a p~ir 114~6~6 of knock-off ingers 22, 22' which are dispc>sed in spaced parallel relation to one another in the dimension perpendieular to the plane o Fig. 1, as is evident in the plan view of Fig. 2 . The shape of fingers 22, 22' is not of particular importance, the only requirements being that they have adequate strength to withstand substantial mechanical impact applied against their extreme outward ends. To this end, the fingers, as seen in the drawings, can be given a roughly dish-shape, with one side edge extending nange-like vertically as at 23, 23' for improved resistance to bending in bo,h planes. The flange edges 23, 23' can serve as a convenient p~int for en-gagement with the lower ends of wires 16, 16', each such edge being per-forated for engagement with hooks bent for that purpose in the lower wire ents, A supporting stub shaft Z6 i8 affixed to a pair of the loosn frame (not shown) and on shaft 26 are pivoted a pair of identical rocker arms 28, 28' extending generally vertically upwardly from the axis of shaft 26 in axially spaced apart relation, again best seen in Fig. 2. At their upper ends, each rocker arm 28, 28' carries a follower roller 30, 30' thereon and intermediate their ends, each arm carries a rightwardly projecting hammer 30, 30'. The axes of the hammers and knock-off fingers are so related that they lie in pairs, one hammer and one finger, in generally common planes in one direction (the vertical direction, as appears in Fig.
- 2). In the other direction ~i. e., as shown) axes of the respective pairs of hammers and fingers are offset or separated so as to be out of regis-tration when the knock-off fingers are actuated in the solid line position seen in Fig. 1 but are in registration when the fingers are situated in the dotted line upwardly displaced position. The front ends of the hammers are preferably notched or otherwise contoured for non-slipping engage-28 ment with the ends of fingers 22 22'.
1146~346 Each of the follower rollers 32, 32' rides on the peripheral ~urface of a corresponding cam 34, 34' mounted in axially spaced relation on the crankshaft of the loom 36 for rotation therewith. The cams 34, 34' are identically contoured so as to each provide a high region or lobe 38, 38' at one point thereon which is preceded by a ramp 40, 40' and followed by a gradually tapering transition 42, 42' which merges into a low region 44, 44' equal to about 180 of the cam periphery. While the cam contours are preferably the same, they are arranged in out of phase relationship on the loom crankshaft so that the respective lobes thereof move into contact with the corresponding follower rollers at different points on the loom cycle.
The rocker arms are biased into contact with the cam peripheries, as by springæ 45, 45' and the starting positions of the cams on the crankshaft can be adju6ted individually by means of set screws or the like (not shown).
In general, the geometry of the cams in relation to the followers, rocker arms and knock-off hammers is such as to cause each rocker arm and associated hammer to pivot between a retracted position spaced away from, i. e. leftwardly in Fig. 1, the extreme tip of its associated knock-off finger when the follower roller rides on the low section 44, 44' of the cam, and a projected operative position in which the knock-off harr~ner overlies its corresponding knock-off finger, as the latter is in full line position, when the follower roller makes contact with the high portion or lobe 38, 38' of the cam.
The knock-off head 18 is supported for horizontal reciprocating movement on a guide bracket 46 which is fixed on stub shaft which termi-nates at its upper end at a more or less frusto-conical shaped guide tongue 48 of reduced thickness so as to project through a vertical slot passing through at least the mid-section of thc knock-off head 18. The knock-off 28 head can, for example, be constructed of two matching side sections 47, ~46~46 47! united in 3paced apart relation so as to define a vertical slot 49 ~Fig.
Z) for penetration by tongue 48, each such qide qection carrying its own rigid knock-off finger. Below tongue 48, bracket 46 has increased thick-n¢~s, thereby forming opposed shoulders 52 (only one of which is visible in the drawing) and knock-off head 18 is thus supported for horizontal recipro-cating movement on bracket 46 generally horizontally along a path fixed by tongue 48. A tension spring 54 stretches between tongue 48 and head 18 to bias the latter toward the let in Fig. 1.
The end of knock-off head 18 opposite to fingers 22, 22' is affixed to the end of a rigid knock-off rod 56 which at its opposite end is pivoted to thè control handle 59, usually referred to as the "shipper" handle 59, of the loom, the connective arrangement being such that the solid line pc!sition of the knock-off head corresponds to the "on" or operating position of the operating handle. In this particular case shown, the shipper handle 59 occupies "on" position when pivoted clockwise and "off" position when swung counterclockwise, and the pivot axis of the handle itself, therefore, lies above the point of pivotal connection of the knocX-off rod 56 thereto.
The arrangement just described operates in the following manner:
While the loom is operating normally, the actuating levers 14, 14' of the respective stop solenoids 10, 10' remain in depressed position so that knock-off head 18 likewise occupies a depressed normal operating position - ~hown in solid lines in Fig. 1. As the crankshaft 36 rotates, each of the cams 34, 34' turns 360 during each weaving cycle and cause3 each of the rocker arms 28, 28' to oscillate back and forth in timed relation to such rotation. The hammers 30, 30' thus are consequently displaced to and fro in relation to the corresponding knock-off fingers, but as long as the knock-off head remain~ depressed or disabled, hammers 30, 30' pass 28 freely above the upper limits of iingers 22, 22' without contactina the 1146~46 same, and ;he weaving continues without interruption. When, however, either a wet or warp yarn breaks, the control signal generated by the corresponding conventional breakage detecting means i8 applied to the corresponding stop solenoid which actuates its armature to pivot the corres-ponding actuating lever upwardly. This lifts the corresponding lift rod 16, 16', thereby pivoting the knock-off fingers 22, 22' connected thereto up-wardly into the oscillating path of the associated hammer 30, 30'. Then, as the cam shaft continues to turn, the rocker arms will be rocked in their turn toward the corresponding knock-off finger so as to impact against such finger in its upwardly displaced position, creating a mechanical im-pul~e which is transmitted to knock-off head 18 and through rod 56 to the loom shipper handle driving it to its "off" position, causing the loom to ~top.
Since each of cam9 34, 34' corresponds in function to a particular type of defect, either warp breakage or weft breakage, and since the relative positions of the cams on the cranlcshaft can be adjusted, it becomes possible to control the timing of the knock-off action selectively to match the needs of the particular kind of defect. Such adjustment will naturally have to be made on a loom by loom basis; the driving mechanism of each different type of commercial loom has its own peculiar braking time con-stant and the effect of inertia will to some extent be different for each given loom but by observing the inertia and the braking time constant of a specific loom, the respective cams 34, 34' can, by trial and error, be arranged on crankshaft 36 so that they result in the loom coming to a halt at the proper points in its operating cycle for the defects in guestion. In the course of repairing a defect, the defect sensing means will be returned to its normal operating position, and the respective stop solenoids are re-28 set to their operating position, thereby returning the knock-off head to its _ 9 _ - ~1461346 depressed or disabled normal operating position before the shipper handle i8 pivoted to restart the loom. lt should be stated that the peripheral dis-placement of cams 34, 34' seen in Fig. 1 is selected primarily to distin-gui~h between the two cams and is not intended to represent actual illus-trative operating positions thereof which would in any case have to be tailored to the particular loom, as already stated.
It can be added, howe~er, that in general~ the optimum stopping point for purposes of repair of a filling defect is at approximately 200-210 of the cycle, while for a warp defect, the best stopping position is around 320 of rotation, keeping in mind in the latter case the need for the lay to be sufficiently remo~red from front dead center as to minimize the chance of a set-mark.
The combined stop motion of the present invention is also ideally adapted for utilization in fùrnishing the loom with the capability for single-pick operation, i. e. the insertion of a single weft and then coming auto-~natically to a halt. To this end, one of the stop solenoids 10, 10', prefer-ably the weft solenoid 10 for reasons to be explained shortly, is connected through a flip-flop 60 and a manual pushbutton switch 62 to a source o control current 64. When pushbutton 62 is closed either just before or simultaneously with mo~rement of the shipper handle 59 to "on~ position, flip-flop 60 is activated so as to actuate the stop solenoid 10 which causes the knock-off head 18 to be lifted to an enabling position with one of its knock-of fingers in position to be engaged by a knock-off hammer during the immediately following cycle of the loom. The flip-flop 60 can be re-set in any convenient way and, for sake of illustration, the extreme lower end of the shipper handle is provided with a magnetic tip 66 which is adapted to cooperate with a magnetically attractable switch 68, such as a 28 Hall effect switch, situated adjacent the path of the shipper handle end when ~l146~6 the latter is in its full "off" position. Thus, when the stop motion functions to knoclc off the loom due to actuation of ~he stop solenoid, the moven~ent of the shipper handle to its off position automatically resets flip-flop 60 in readiness for the next cycle.
Given the fact that the loom stops fairly late in its cycle in the event of the occurrence of a defective pick or warp breakage, stoppage of the loom within the same cycle wherein the defect occurs would impose enormous stress on the loom components and, consequently, it is in-tended in the practice of the present invention for the inertia of the loom 10 ' to carry its operating components, especially the lay, well into the sub-- sequent cycle, stopping at one of the predetermined points therealong as ~pecified above. This means, of course, that when a filling defect has occurred, the defective pick has already been beat up into the fabric and the heddlés have shifted position for the insertion of the following pick which has already been inserted across the open shed. In order to repair the defect pursuant to this invention, the inserted weft for the next cycle i8 removed by hand, the loom having been brought to a stop in po~ition appropriate for such removal. Next, the heddles must be returned to the position occupied by them when the defective pick was inserted and the single pick operation feature of the present invention enables this to be done by mere actuation of the single pick control by the loom attendant.
The heddles are thereby reversed, open~ng the shed to enable the defect-ive pick to be removed without interference. In the meantime~ a fresh pick has been inserted into the shed opened by reversal of the heddles and the lay has been positioned ready to resume the normal weaving operation.
In order to minimize the opportunity for set-marks to be created when the loom is restarted, it is preferred that the weft stop solenoid be integrated 28 into the single pick operation, receiving the control signal from the . _ _ . . _.. _ . _ . ___ , . . , ... , .. . . .. _ . . " .. " .........
~146(346 flip-Ilop 60 and thereby stopping the loom in the vicinity of 200-220 of its cycle, which i8 ideal for eliminating set-marks.
.A further consideration involved in the selection of the stopping point of the loom ollowing single-pick operation as well as or a wet de-fect, i8 the effect of the stopping point on the manipulation o the weft it-~el. While the system o the present invention can be employed quite successfully with conventional comn~ercial looms of all types, it is also especially useful in association with a loom of the fluid insertion type, and while various different looms operating in this way have been or are being designed, and all can in principle utilize the system of the invention with good results, a particular preferred fluid weft insertion loom is disclosed and claimed in application Serial No. 356,160 filed in the name of Charles W. Brouwer et al on July 15~ 1980 and commonly assigned herewith, to the tescription of which reference may be had for a fuller understanding of its operation. In the loom of application Serial No. 356,160, air or other inert compressible medium is delivered under predetermined pressure to the throat of an insertion noz~le and an important feature of that loom is tbe manner in which the flow of air to the nozzle is controlled to limit the duration of the air flow in the manner of a pul~e, the pressure of the air in this pulse being sufficiently high that this pulse contains all of the energynecessary to transport a typical yarn across the width of a typical commer-cial loom, say at least about 48". Because of this high air pressure, the weft yarn passing through the nozzle throat for insertion thereby into the warp i8 subjected to very substantial stress, particularly since the pre-ferred nozzle of the above-identified application is designed to impart supersonic ~relocities to the air flow downstream of it~ throat and the yarn i8 exposed to such high velocities.
28 It has been found that if the yarn i~ exposed to such intense air flow ~ 12 -~146~46 when it i8 being re~trained against movement, either before or after its insertioD into the loom shed, the stress upon the stationary yarn will be deleterious to that yarn. For this reason, th0 stopping point of the loom must be coordinated with the timing of the pulse or other ilow of the wet insertion medium 60 as to avoid stopping the loom, while the pulse control device remains substantially operative. Damage to the yarn is minimized, however, if the earliest stopping point of the loom is subsequent to termi-nation of the pulse of weft inserting medium; although in practice, some overlap is permissible provided the pulse is in its terminal phase at that point and is already undergoing a loss in pressure on the way towards imminent shutdown.
There i8 another advantage of the system of the invention which is of significant merit in actual commercial practice. The stopping positions of the heddles of the loom, which typically project in their open or spread position vertically well above the body of the loom and thus are readily visible at some distance, are different with the two kinds of defects in question, the heddles stopping in closed or together position for a warp de-fect and in well separated or open condition for a weft defect. Hence, simply by observing the position of the heddles, the operator is immedi-ately informed as to the kind of defect which requires attention and may, therefore, organize the approach to be taken for repair to minimize wasted time and effort.
The location of the present stop motion on the loom frame is ob-viously subject to some variation. As mentioned above, the driving cams are preferably mounted directly on the loom crankshaft, which might in-fluence its location, but this is not essential because the cam~ could be mounted elsewhere and driven in synchronism with the crankshaft by ~neans 28 of intermediate gearing, a timing belt coupling or the like. One useful 1~6~6 location i~ adjacent the inside of the side frame member neare6t the 6hipper handle ~which i8 UBUally actuated at front corner but well clear of the path~ of movement of operating components, such as the heddles and lay) to avoid interference therewith. The in~tant sg~tem ob~riously takeR
up relatively little space ~ince the axial thickness of its individual elements,and therefore the overall axial thicknes6, need only be such as to achieve the required mechanical strength and durability for long term ~peration.
From the foregoing it will be seen that the pre~ent invention pro--~naes unique and ad~rantageous method and apparatus for stopping a loom upon detection of a warp or filling defect with the variou~ mechanisms of the loom, particularly the lay and harnesses, in the optimum position for correction of a warp or filling defect. In practice with the prior art the repair of filling defect~ i8 a laborious and time-consuming task. For ex-mple, in effecting such repairfi on conventional ny shuttle looms it has been nece~ary, once the loom is ~topped, for the loom attendant to rotate the loom crardc~haft baclcward~ manually to relocate the lay and other operative loom component~ at a desired starting position to avoid the ~et-~rk problem. Next, the operator is required to remove the faulty pick.
Thereafter, the operator grasps and holds the filling end from the bobbin in the ~huttle with one hand while manually propelling the shuttle through the ~hed to insert a "good" pick in the shed for beat-up.
- In clear contradistinction to the foregoing, the present invention operates upon the detection of a faulty pick to ~top the loom automatically on the next cycle after the faulty pick has been beat into the fabric. This ~topping, ae previou~ly mentioned, occur~ when the loom is approximately 270 into the next cycle. When the loom is thus stopped the operator manually removes the pick then resident in the shed as fully explained in 28 prior cited patent application Serial No. 3~6,160. At this point, ~; \ ~ ~ 14 -~6~6 since the heddles mu$lt be reurned to the pOSitiOI-S they were in when the faulty pic~c was inserted into the fabric, that i6, the heddles must be re-versed to permit ready removal of the faulty pick. This is achieved by actuating pushbutton 62 which automatically operates the loom through one cycle with the loom stopping at approximately the 200-220 position. In the course of this single pick operation of ihe loom the shed is reversed to permit easy manual removal of the faulty pick from the fabric while, at the same time, causing a fresh pick to be inserted into position in the shed.
Additionally, the loom mechanisms are optimally positioned to beat up the further pick once the loom is restarted with the lay impacting against the further pick under its full operating force to thereby preclude a set-mark in the fabric at the locus where the filling repair has been made. There-fore, filling repairs as just described can be effected some three or more time~ faster in practice with the present invention than is possible with prior art techniques while, at the same time, aYoiding undesirable set-mark6 in the woven fabric.
While a preferred embodiment of the invention has been described, with various preferred aspects being identified, it will be understood and appreciated that the invention is not intended to be limited in its scope to these preferences as other alternatives and options will be readily avail-able within the skill of the art and will be obviously suggested by what has been specifically described and illustrated. Therefore, the invention is not intended to be confined in its scope to any specific characteristics ex-cept where expressly required by the accompanying claims.
;~8 ~ 15 -
Claims (7)
1. In a yarn stop motion for a loom having a driving means for driving the same in a repetitive cycle to insert a weft yarn between separated groups of warp yarns to form fabric and including separate de-tection means for detecting the occurrence of a breakage in the weft yarn or in any of the warp yarns, an improved combined warp and filling stop motion effective to stop the loom drive in different positions within its cycle corresponding to the type of yarn breakage, which comprises:
- a pair of impacting means each mounted for independent movement to and fro along a fixed path;
- separate drive means for the respective impacting means, each such drive means being driven from said loom driving means in individually adjustable predetermined timed relation to the loom cycle;
- loom control means operatively connected to the loom drive means and movable between a normal loom running position and a loom stopping position;
- impact transmitting means operatively associated with said control means and displaceable between a retracted position outside the paths of both said impacting means to a projected position within both said paths to receive when in said projected position the impact of the respective im-pacting means and transmit such impact to said control means to move the same to its loom stopping position; and - separate actuating means for said impact transmitting means responsive to each of said weft detecting means to cause displacement of said im-pact transmitting means to its projected position in the event of the activation of the corresponding detecting means, whereby the response of the combined stop motion to either warp or weft breakage is delayed according to the predetermined timing of the corres-ponding drive means for a period which can be adjusted to cause stoppage of the loom at different positions for the two types of yarn breakage.
- a pair of impacting means each mounted for independent movement to and fro along a fixed path;
- separate drive means for the respective impacting means, each such drive means being driven from said loom driving means in individually adjustable predetermined timed relation to the loom cycle;
- loom control means operatively connected to the loom drive means and movable between a normal loom running position and a loom stopping position;
- impact transmitting means operatively associated with said control means and displaceable between a retracted position outside the paths of both said impacting means to a projected position within both said paths to receive when in said projected position the impact of the respective im-pacting means and transmit such impact to said control means to move the same to its loom stopping position; and - separate actuating means for said impact transmitting means responsive to each of said weft detecting means to cause displacement of said im-pact transmitting means to its projected position in the event of the activation of the corresponding detecting means, whereby the response of the combined stop motion to either warp or weft breakage is delayed according to the predetermined timing of the corres-ponding drive means for a period which can be adjusted to cause stoppage of the loom at different positions for the two types of yarn breakage.
2, The combined warp and weft stop motion of claim 1 wherein said actuating means for said transmitting means comprises two separate solenoids, one connected to said warp detecting means and the other to said weft detecting means, each such solenoid having its armature linked to said impact transmitting means to displace the same upon its actuation.
3. The combined stop motion of claim 2 including a separate im-pact transmitting means for each of said impacting means.
4. The combined stop motion of claim 3 wherein said impact transmitting means comprises a generally horizontally movable rod connected at one end to said loom control means and carrying at its other end two individually displaceable fingers receiving the impact when dis-placed from the corresponding impacting means.
5. The combined stop motion of claim 1 wherein said drive means for said impacting means comprises a pair of cams driven in synchronism with the loom operating cycle, each such cam having high and low regions on its periphery, and said impacting means includes follower means en-gaging the periphery of the corresponding cam to achieve a to and fro movement in synchronism with the loom cycle, the relative peripheral positions of the high and low regions of said cams being different with respect to said loom operating cycle whereby the respective impacting means are driven at different points along said cycle.
6. The combined stop motion of claim 5 wherein said cams are mounted for individual adjustment relative to the loom cycle to permit the timing of the corresponding impacting means to be varied.
7. In a yarn stop motion for a loom having a driving means for driving the same in a repetitive cycle to insert a weft yarn between separated groups of warp yarns to form fabric and drive means being adapted to be halted upon delivery thereto of a control impulse and in-cluding separate detection means for detecting the occurrence of a break-age in the weft yarn or in any of the warp yarns, an improved combined warp and filling stop motion effective to stop the loom drive in different positions within its cycle corresponding to the type of breakage, which comprises:
- two separate means for generating separate control impulses in timed relation to the operative cycle of said driving means at different pre-determined points in said cycle;
- impulse transmitting means operatively extending between said impulse generating means and said loom drive means in normally disabled condition; and - means operated in response to detection by either of said detecting means of breakage in one of said yarns for placing said impulse transmitting means in enabled condition to transmit said control impulse to said loom drive and cause stoppage of the loom in position corresponding to the timing of said impulse generating means.
- two separate means for generating separate control impulses in timed relation to the operative cycle of said driving means at different pre-determined points in said cycle;
- impulse transmitting means operatively extending between said impulse generating means and said loom drive means in normally disabled condition; and - means operated in response to detection by either of said detecting means of breakage in one of said yarns for placing said impulse transmitting means in enabled condition to transmit said control impulse to said loom drive and cause stoppage of the loom in position corresponding to the timing of said impulse generating means.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US22320481A | 1981-01-07 | 1981-01-07 | |
| US223,204 | 1981-01-07 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1146046A true CA1146046A (en) | 1983-05-10 |
Family
ID=22835513
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000375501A Expired CA1146046A (en) | 1981-01-07 | 1981-04-15 | Selectively timed combined warp and weft loom stop motion |
Country Status (2)
| Country | Link |
|---|---|
| CA (1) | CA1146046A (en) |
| GB (1) | GB2090620A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DD238306A3 (en) * | 1984-05-02 | 1986-08-20 | Greika Greiz Veb | ARRANGEMENT FOR FADENUE MONITORING OF A PROTECTIVE WEAVING MACHINE |
| DE3933616C2 (en) * | 1989-10-07 | 1998-07-02 | Dornier Gmbh Lindauer | Weaving machine for fabrics sensitive to position, in particular twill fabrics |
| JP3157776B2 (en) * | 1998-04-17 | 2001-04-16 | 津田駒工業株式会社 | How to start the loom |
-
1981
- 1981-03-26 GB GB8109523A patent/GB2090620A/en not_active Withdrawn
- 1981-04-15 CA CA000375501A patent/CA1146046A/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| GB2090620A (en) | 1982-07-14 |
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