US2884016A - Loom control means - Google Patents

Description

April 28, 1959 K. E. SANDERSON ET AL LOOM CONTROL MEANS Filed April 16, 1956 2 Sheets-Sheet 2 INVEN TOR. KENNETH E.SANDER5ON ROBERT E. MILLKEJAN A TTORNEY United States Patent LOOM CONTROL MEANS Kenneth E. Sanderson, Hopedale, and Robert E. Milligan,

West Medway, Mass, assignors to Draper Corporation, Hopedal'e, Mass., a corporation of Maine Application April 16, 1956, Serial No. 578,409

Claims. (Cl. 139--336) This invention relates to control means for starting and stopping looms, and more particularly to improvements in means for latching and releasing a shipper lever during the various phases of loom operation.

It is a general object of the invention to devise a loom control means which shall act more quickly to stop the loom once a signal has been given.

A more specific object is that of providing means to stop the loom with less noise and shock, and to obviate the rebound of the shipper and control parts.

Another object of the invention is that of devising a shipper lever and control system for a loom in which the lever may be held in position while the loom is running, by electrically energized means which may release the lever at a signal from. any one of several stop motions and which shall require very little current.

A further object is that of providing such latching means which shall be in circuit with a stop motion or motions and which when released shall act to complete a circuit through a shunt line to cut out the warp stop motion.

Another object is that of devising such mechanism which, when the loom is knocked off manually, will be displaced to close a shunt circuit for releasing the latch.

Another object is that of so devising the mechanism that it may easily be reset by pulling the shipper handle to operating position.

Other objects will become apparent from the following more detailed disclosure.

It is customary to equip looms for weaving with a knock-off lever which is used to start and to stop the loom manually, and which is also automatically released to stop the loom when one of the various stop motions gives an indication for that purpose. These stop motions frequently function through a circuit and electromechanical means to retain and to release the lever or other mechanism effecting the stopping function.

Normally, such a shipper lever is linked up to a clutch or clutch and brake control and functions through a toggle or overcenter means in a Way to hold the clutch in engagement without stressing the linkage. In other words, the mechanism requires force applied to shipper parts in its setting, but none to maintain it set.

This serves well in some ways but too much time is required after a signal from the stop motions before the loom can be brought to a complete stop. Again, a more violent knock-off action than should be tolerated is often experienced and the rebound of parts, a thing in itself more or less annoying, gives added trouble arising from a momentary reengagement of the clutch which may accompany that rebound. Much of this results since it requires use of some force greater than that of the overcenter device or the like which must come into action as a result of the signal, whereupon the clutch may then Y, 2,884,016 Patented Apr. 28, 1959 be disengaged and the brake applied. All this is a source of considerable trouble with higher speeds of weaving since the time consumed in stopping after a filling or warp break may be so great as to require more work on the part of the weaver before the loom can be restarted.

According to the invention a power transmission unit including a clutch and brake is controlled by a linkage from a shipper lever which must always resist forces tending to release the clutch and to apply a brake. There is no movement of a toggle or other mechanism to an overcenter position. The stressed linkage is thus in readiness to move immediately to a clutch-out brake-on position as soon as a signal acts electromechanically to withdraw a lever latching means or, as herein shown and preferred, may merely release such a latch.

To do this and still use little current, a particular arrangement of parts and disposal of centers of a latching system has been devised which is simple, quick-acting and eflicient and which also requires only a small current to maintain it. It functions in a simple electrical circuit which has decided advantages and is itself free from troubles such as frequently do render such stopping de vices impractical.

The invention will be described in detail by reference to a preferred embodiment thereof as illustrated in the accompanying figures of drawing, wherein:

Fig. 1 is an end elevation of a weaving machineto which the invention has been applied.

Fig. 2 is a view of part of the mechanism of Fig. 110 an enlarged scale.

Fig. 3 is a section showing the mechanism of Fig. 2 as seen from the front.

Fig. 4 is a view of the latching means in a position it passes through upon stopping the loom by hand.

Fig. 5 is a detail of part of the linkage by which the clutch and brake are set.

Fig. 6 is a diagrammatic view of a circuit employed.

Referring to Fig. 1, the invention is shown as applied to a loom of the type described in United States Patent 2,604,123, although it is applicable to all looms. Among other parts, such a loom has loomsides 10, a structure at each end including casing 11 and brackets 12 and 13 within which casing is mounted for oscillation part of a filling inserting mechanism. Such mechanism is oscillated by means of a crank 14 and connecting rod 15, said crank being fixed at the end of a shaft 16. All functional parts of the loom are driven by a motor 17 which is preferably of the type in which a motor, clutch and brake are combined as a unit and control of the loom involves engaging the clutch to drive, disengaging it and applying a brake to stop, or neutrallizing the whole unit by disengaging both clutch and brake in which case the machine may be slowly passed through its motions by hand. Such a power transmitter unit is shown in United States Patent 2,650,995.

Referring to Figs. 1 and 5, the clutch-brake unit is under the immediate control of an arm 18 pivoted at 19 and adapted to affect the position of a plate within the unit housing which may alternately be placed in driving engagement with a cooperating clutch plate or with a fixed brake member. This arm 18 is always biased by a spring 20 to the braking position.

At the opposite end of the motor housing a plate 21 bolted to that housing pivots at 22 a swinging crank arm 23 with a stop projection 24. At its free end this arm has connections 25 and 26 in the form of shoulder screws or the like, to which are connected links 27 and 28. One connection is provided below the arm and one aboveto assaote avoid interference. Link 28 is also connected at its opposite end to the end of arm 18. Of course, both links 27 and 28 are adjustable as to their length.

The projection 24 engages against a stop screw 29 threaded through a lug 30 on plate 21 and is locked in position by a lock nut 31. Adjustment of screw 29 limits the swing of arm 23. It is to be noted that the pivot 26 between the link 28 and arm 23 never moves past the overcenter position with regard to pivot 22 so that to hold the clutch in engagement, force must always be applied to link 27.

This link 27, Figs. 1 and 2, is connected at its forward end to a depending arm 32 by a pivot pin 33. Arm 32 is fixed to shaft 34 by securing its hub 35 to the shaft as shown, and this hub extends upwardly at 36 to carry an arm 37. These arms and hub constitute a shipper lever and a knob 38 at the top serves as a convenient grip by which it is manually engaged. At the opposite end of shaft 34 a similar arm and knob may be provided.

A latching unit is applied to the lower extending end 39 of the shipper lever to hold it in position to engage the clutch. Withdrawal of the latch, of course, permits all parts involved to move under the influence of spring 20 to a. clutch-released brake-applied position.

' This latch involves parts which facilitate setting, holding with a light force notwithstanding the heavy bias at the link 27 and also-hand manipulation. The unit is mounted at the loom-side on a bracket 40. A bell crank having arms 41 and 42 is pivoted at 43 on this bracket and its arm 42 carries a stop screw 44 which engages against an abutment 45. The screw is locked in an adjusted position by nut 46.

At its extreme lower end arm 42 has connected to it a spring 47, the opposite end of which attaches to an anchor post 4-3. The reason for this spring will be explained in due course.

At the end of arm 41 a pin 49 serves as a pivot for a lever 50 having an arm 51 and a depending arm 52 which functions as an armature. At its end arm 51 mounts a roller 53 which engages the end 39 of the shipper lever. A spring 54 attaches at one end to arm 51 and at its other end to a lug 55 projecting from the hub of the bell crank.

The bracket 40 is built out at 56 to from a support for a core 57 of the solenoid 58 which carries a coil or winding 59. A web 68 part of the holding magnet and extending from the bracket also acts as a stop for the armature 52 and as a support for other parts to be described. The armature is provided with a stop screw 61 threaded through its end to bear against the end of web 60. A nut locks the screw in position. By spacing the armature a proper gap or distance from the core 57, the holding force may be varied to something less than the maximum provided by the solenoid. A pull of about 3-4 pounds on the armature at the core functions very well.

The center 49 and point of contact of roll 53 with the end 39 of arm 32 are in a line which i not quite perpendicular to the length of arm 32; in fact, they lie in a line a few degrees short of a dead center position so that pressure of the arm as influenced by link 27 is always tending to displace the roll and arm 51. That is also supplemented by the pull of spring 54. These two forces are resisted by the solenoids pull so that when once set, there is no danger of release except by intended operation as will be explained.

When released, the parts may move until a stop 51 bears against the arm 41.

To reset the device once it has been tripped, it is only necessary to pull the shipper lever slightly past the running position. A Y-shaped arm 62 having arms 63 and 64 is pivoted at 65 to a lug 66, a part of the bracket 48. Arm 63 is always behind the end 39 of the shipper lever while arm 64 engages under the roller 53. As the arm 32 is moved to the dot-and-dash line position of Fig. 2, it rocks the Y-shaped arm as shown and pressure of its I be broken.

4 arm 64 under roller 53 swings lever 50 to a position in which it may be electrically held against displacement.

It is to be understood that spring 54 is relatively weak but that spring 47 has considerable strength; during all functions except manual knock-01f, the arm 41 and thus center 49 remain stationary.

Arm 52 carries a contact member 67 which coacts with a spring contact 68 insulated from the bracket, but connected in circuit as will be explained. The contact 67 is grounded.

The circuit similar to that of United States Patent 2,707,977 is shown at Fig. 6. Current is supplied to the circuit through a rectifier 69 the output of which passes through a resistance such as the lamp 70 and in lines 71, 72 and 73 to the solenoid 58. It also passes a filling stop motion 74 or other means by which the circuit may Circuit through this solenoid is completed through grounds 75 and 76, the latter of which has associated with it a condenser 77. This is for the purpose of minimizing the ripple in the current from the rectifier and actually raises the voltage at the solenoid about four volts from what would otherwise be obtained.

In a second branch of the circuit current is conducted to a warp stop motion 78 through line 79 and may be grounded at 80 whenever a drop wire makes contact in the well known manner. As that occurs, the voltage at solenoid 58 drops to a value such that the armature is re leased thereby permitting arm 51 to swing out from the position of Fig. 1 to the dot-and-dash line position of Fig. 4 At that time the contacts 67 and 68 complete a circuit through shunt line 81 to ground. That by-passes the warp stop motion to divert most of its current soa s to reduce sparking at the electrodes.

This shunt line also serves when knocking off the loom manually since then, as shown in Fig. 6, the forced swing ing of the arm 32 cannot directly displace arm 51 and armature 52 by swinging them about their pivot, but instead, forces the parts bodily downwardly swinging the support arm 41 about pivot 43 stretching spring 47 until a contact is made at 67-68, whereupon current is shunted to ground dropping voltage at the solenoid so that the armature is released.

At times it is desired that both the clutch and brake be disengaged so the machine may be turned by hand. An arm 82 with knob 83 pivoted at 84 serves so to set the parts that that may be done. The hub 85 also has a second arm 86 at the end of which is a roller 87 engageable against arm 32. Pivot 84 is fixed at the end of an arm 88 attached to the loom framework. When swung against a stop (not shown), the parts are so moved that links 27, 28, etc., are held in an intermediate position.

To review the operation briefly, the current being on, shipper handle 38 may be gripped and the lever pulled forward as far as it will move at which time the clutch will be engaged and the loom started. The Y-shaped arm is swung as in Fig. 2 to set the lever 50 so it is gripped by solenoid 58 and the loom will run then until stopped either automatically or manually.

If a warp thread failure grounds current through switch 78, the voltage drop in line 73 causes solenoid 58 to let go so that the shipper mechanism is free to move to clutch-out brake-on position. Should a filling break open the circuit at 74, the same thing happens. In either event contacts 67 and 68 complete a shunt circuit to ground so that the entire circuit at the solenoid side is for practical purposes dead until the device is reset.

Upon stopping manually the shipper lever is used to force arm 41 about its pivot against the tension of spring 47 until contacts 67 and 68 complete a ground through the shunt. The same condition of stopping then exists as before.

It can be seen that due to the angular disposition of parts, when running, the arm 32 and link 27 approach a straightened condition so that a minimum of pressure at the end 39 is required to hold against spring 20 at the arm 18. Then the arm 51 is likewise acting more nearly as a strut than as a lever and the current needed to hold armature 52 becomes very low.

. When released, however, the parts which have no great inertia move directly and quickly to a stopped position. No timed actuators are required and none of the parts need move through or past an overcenter position. All functions become more direct, simple, and since the loom may be stopped in a minimum of time, speeds may be increased without the difiiculty heretofore experienced of having the mechanism continue in operation too long before coming to rest.

There are no positively operated means needed to assist the knock-off function and for that and other reasons the forces involved at that time are lessened. There is less shock and noise experienced at the time and, more important, the mechanism does not rebound. In some cases previously experienced where the control has passed through an overcenter position or been influenced by some timing means for kicking the members through such position, there has been a rebound of parts even to the point where the clutch may momentarily engage again.

Little effort is needed to start the loom and when the shipper lever is released, it does not move belatedly but with terrific force as has sometimes been the case heretofore. There is no danger of its injuring the loom operator if it does develop that he should be in the way of the lever as it is released.

Again, when getting the loom going after a smash, the weaver may hold the shipper lever on and there is no pounding of parts trying to stop the loom, since, of course, some of the warp threads being broken out, the stop motion will continuously indicate a break. With the present mechanism, that makes no difference, since the warp stop motion functions and is then more or less isolated from the circuit by the shunt to ground.

Heretofore, the stop motion has been disconnected or otherwise rendered inactive while drawing in after a smash, and then when the loom has been started, the weaver may forget and leave the loom running with no stop motion at the warp. That cannot happen with the means herein described. The loom must be in condition to run fully protected before it can be started and remain running.

While one embodiment of the invention has been disclosed, it is to be understood that the inventive concept may be carried out in a number of ways. This invention is, therefore, not to be limited to the precise details described, but is intended to embrace all variations and modifications thereof falling within the spirit of the invention and the scope of the claims.

We claim:

1. In a loom having knock-off means including a shipper lever movable about a pivot and to which is connected a link by which a loom drive unit is maintained in a power transmitting relationship, a shipper latch means, part of which has a near dead center position with respect to said lever, a pivot for said latch means, said pivot, latch means and lever being so disposed that said latch means opposes movement of the lever when in said near dead center position, and a solenoid for holding said latch means in its effective position.

2. In a loom having knock-off means including a shipper lever movable about a pivot and to which is connected a link by which a loom drive unit is maintained in a power transmitting relationship, a shipper latch means, part of which has a near dead center position with respect to said lever, a pivot for said latch means, said pivot, latch means and lever being so disposed that said latch means opposes movement of the lever when in a near dead center position, an extension of said latch means forming an armature, and means for holding said latch means in effective position which comprises a solenoid in circuit with a stop motion.

3. In a loom having knock-off means including a shipper lever movable about a pivot and to which is con nected a link by which a loom drive unit is maintained in a power transmitting relationship, a shipper latch means, part of which has a near dead center position with respect to said lever, a pivot for said latch means, said pivot, latch means and lever being so disposed that said latch means opposes movement of the lever when in a near dead center position, an extension of said latch means forming an armature, and means for holding said latch means in effective position which comprises a solenoid, a means including a circuit and curren con trol means through which said solenoid is energized, and a stop motion circuit for diverting current to drop the voltage at said solenoid to release the latch means.

4. Mechanism as defined in claim 3 in which a shunt circuit is provided in the stop motion circuit including contact members one of which is a part of said latch means.

5. In a loom having knock-off means including a shipper lever movable about a pivot and to which is connected a link by which a loom drive unit is maintained in a power transmitting relationship, a shipper latch means, part of which has a near dead center posi tion with respect to said lever, a pivot for said latch means, said pivot, latch means and lever being so disposed that said latch means opposes movement of the lever when in a near dead center position, said pivot for the latch means comprising a two armed lever, a pivot therefor and a spring and stop means normally serving to hold said lever in one position but effective at manual knock-cit of the loom to permit the lever to swing thereby to displace the pivot for the latch means and to release the shipper lever.

6. In a loom having knock-off means including a shipper lever movable about a pivot and to which is connected a link by which a loom drive unit is maintained in a power transmitting relationship, a shipper latch means, part of which has a near dead center position with respect to said lever, a pivot for said latch means, said pivot, latch means and lever being so disposed that said latch means opposes movement of the lever when in a near dead center position, said pivot for the latch means comprising a two armed lever, a pivot therefor and a spring and stop means normally serving to hold said lever in one position but effective at manual knock-off of the loom to permit the lever to swing thereby to displace the pivot for the latch means and'to release the shipper lever, and electric circuit means including a solenoid, said circuit including a contact means for completing a circuit to drop the voltage at the solenoid so it will release the said latch means.

7. Mechanism as defined in claim 6 wherein said contact means includes one member fixed to said latch means and a second attached to a fixed part of said loom through which the current to the solenoid may be diverted to ground.

8. In a loom having a knock-off means including a shipper lever movable about a pivot, a continuously stressed linkage from said lever to a clutch-brake mechanism controlled thereby, and a means for releasably retaining said shipper leverin a position to engage the loom drive in running position which comprises a two armed lever, a central pivot for said lever, a spring and stop at one arm for maintaining the lever in a normally rigid position, a latch means pivoted at the other arm of said lever comprising a second two armed lever, one arm of which has a near dead center position with respect to said shipper lever and the other arm of which constitutes an armature, a stop motion circuit and a solenoid therein for holding said armature in position so that said latch means shall be held against the shipper lever in a position closely approaching a perpendicular to the lever at point of contact of the latch means and lever.

9. Mechanism as defined in claim 8 wherein an adjustable abutment is provided to regulate the gap be,

tween the armature and solenoid thereby to adjust the holding force exerted upon the armature.

l0. Mechanism as defined in claim 8 wherein contacts forming a part of the said circuit are provided, one said contact being carried by said latch means and being so disposed as to complete a circuit to divert current from the solenoid whenever the latch means is displaced.

References Cited in the file of this patent UNITED STATES PATENTS Bridge June 26, 1906 Robb Dec. 12, 1944 Pfarrwaller Mar. 27, 1951 Butler et al. Jan. 19, 1954

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