Textile machine clutch

Abstract

Apparatus for braiding an article with a filament such as wire wound on a spool. The spool is rotatably mounted on a frame to permit the filament to unwind and pass first through a tensioning device and then around the article to be braided. The spool is under the control of two helical spring brakes. One brake is normally engaged to prevent the spool from turning and is disengaged in response to the tensioning device to permit the filament to unwind. The second brake is normally disengaged and is engaged automatically to stop the spool should the latter begin to turn backward.

Description

The present invention concerns carrier brake means which controls a spool or other material supply source in order to permit feeding of the material from the spool on demand. The brake means must be such that it is incapable of backing up, but will feed on demand.

In the art of feeding material from spools, or other like sources, there are often applications in which it is desirable to maintain the amount of tension on the material being fed from the spool. On some occasions it is desirable to have the tension maintained on the material, even though the spool itself is being moved about, or the point to which the material is being fed and consumed is being moved about, or possibly, even both, may be moved about. A typical example of a difficult application of this type is a braiding machine in which a braided tubular cover is applied, for example, to a hose, or to a conductor of some type. In such applications the body being covered with the braided cover is moved transversely to the plane of braiding while the spools carrying the braiding material are weaved in and out around one another in a maypole effect, within the plane of the braiding in order to accomplish the braiding.

Under such circumstances, there are times when the movement of the spool is such that its movement alone supplies additional material as required in the braiding, and there are times when material must be pulled from the spool at varying rates in order to meet the needed supply.

The present invention anticipates an application in which material is withdrawn from spools, or the like, under conditions where there is movement either of the spools or of the point at which the material from the spools is being consumed. The present invention also anticipates the need to prevent creation of slack by effective braking.

More specifically, the present invention relates to a brake for feeding on demand, including a frame hub having means for attachment to a frame and a brake hub rotatable relative to the frame hub about the axis of a cylindrical brake surface adjacent to the frame hub on the brake hub. A helical brake spring is fixed at one end to the frame hub and surrounds the cylindrical surface of the brake hub, so that it is normally in engagement with that surface. The direction of the winding of the spring is such as to prevent rotation of the brake hub in the direction of feed, since any tendency to rotate in that direction will tighten the brake spring further against the brake hub. A control collar is fixed to the other end of a helical brake spring and movable to displace said spring from the brake hub to thereby permit rotation of the brake hub in the direction of feed. An anti-backup means acts between the frame hub and the brake hub to prevent rotation of the brake hub in the direction opposite that from feed direction.

In preferred embodiments the anti-backup means is also a helical spring, and preferably both springs, the brake spring and the anti-backup spring are attached to the frame hub and engage not only the brake hub, but also the frame hub. For the brake for feeding on demand the brake surfaces are cylindrical outer surfaces adjacent to one another and of the same general diameter. For the anti-backup brake the preferred form includes internal cylindrical surfaces wherein the anti-backup spring is urged outwardly normally into engagement with these internal surfaces. The springs in this case are of the same hand and the hand employed in the brake spring depends upon the direction of rotation required to unreel material on the spool. For a better understanding of the present invention, reference is made to the drawings in which

FIG. 1 is a schematic diagram of reel and brake positions in a braiding machine;

FIG. 2 is a diagram of an individual reel in a braiding machine employing the carrier brake means of the present invention and showing alternative positions for actuator and slide assembly;

FIG. 3 is a sectional view as seen from line 3--3 of FIG. 2 showing a carrier brake means in accordance with the present invention in the environment with the carrier and the spool and having the vertical axis of the spool shown horizontal;

FIG. 4 is a sectional view taken along line 4-4 of FIG. 3;

FIG. 5 is a sectional view taken along line 5--5 of FIG. 3; and

FIG. 6 is a partial plan view from above taken along line 6--6 of FIG. 3.

Referring to FIG. 1, a schematic diagram of spool locations in a braiding machine is shown. Carriers for the spools move around about a body 1 receiving a braided cover moving through the center the carriers moving along sinuous paths about the center. Reels 10 move clockwise along the solid line paths whereas reels 12 move counter-clockwise along the dashed line path. It will be appreciated that the mechanisms involved are conventional in that they provide means for moving the spools over and under and around in varying radial distances.

FIG. 2 shows a diagram of a single carrier system having carrier frame 32, wherein the spool 10 provides a supply of material such as wire 14 for braiding in a tubular form over a body or hose 1, or other conduit. The wire from spool 10 moves around a guide 15, under roller 16, over roller 18 and under roller 20. Roller 18 is a tensioning roller supported on a slide assembly 21, which supports an actuator blade 24 and which is urged by springs 22 and 23, encircling guidance means 25 and 27, respectively, away from clutch actuator 26. As tension in the wire 14 increases the roller 18 pulls the slide assembly 21 downwardly toward the clutch actuator 26. As tension decreases the springs 22 and 23 urge the slide assembly 21 and roller 18 away from clutch actuator 26. As tension increases the roller 18 is pulled toward clutch actuator 26 against the action of springs 22 and 23 until actuator blade 24 is moved into a position to contact clutch actuator 26 on release collar of carrier brake 30, as indicated by the alternative position of actuator blade 24 in FIG. 2, in order to release the carrier brake 30 to permit additional material to be supplied from the spool. Release of the brake 30 to permit more wire to be supplied allows the springs 22 and 23 to urge slide assembly 21 and roller 18, and hence actuator blade 24, upwardly away from the clutch actuator 26 to provide effective braking to prevent creation of slack.

Referring now to FIG. 3, the carrier brake is generally designated 30 and is supported on a reference frame 32, which is here the carrier, which moves as described in FIG. 1. The part of the carrier brake 30 actually supported on the frame 32 is the frame hub 34, which has a bore into which is pressed shaft 36 and thus the latter is rigid with the frame. Shaft 36 in turn carries the spool 10 on bronze bushings on the spool so that the spool may turn on the shaft. The spool is held in place by a quick disconnect coupling 38 which holds it against the carrier brake. The quick disconnect urges lugs 40 into slots 42 milled in the end of brake hub 44, which is rotatably supported on the frame hub 34.

In somewhat greater detail the frame hub, which is a tubular member receiving the shaft 36 and having a radially outward extending flange by which it is bolted to the carrier, the frame 32, also has fixed to it by bolts 46, or other suitable means, a ring 48. The ring 48 therefore forms an integral part of the frame hub and is provided with inner and outer cylindrical surfaces which cooperate with springs. The inner surface is spaced from the tubular portion of frame hub 34 sufficiently far radially outwardly to receive with adequate clearance the anti-backup spring 50. The outer cylindrical surface of ring 48 receives brake spring 52. The brake hub 44 provides similar inner and outer cylindrical surfaces for cooperation with the anti-backup spring 50 and the brake spring 52, which abut the corresponding surfaces of the ring 48 of the frame hub. Both springs 50 and 52 have tangs 50a and 52a respectively by which they are connected to the frame hub. Anti-backup spring is wrapped down as placed in position so that it tends to unwrap and bear against the internal cylindrical surfaces of the frame hub and the brake hub. The brake spring 52 tends to wrap down onto the outer cylindrical surfaces of these two hubs. The normal direction of rotation for the spool to unreel the material stored thereon is in such direction that the hand of the brake spring 52 will cause it to wrap down more tightly on the two hubs. The anti-backup spring is of the same hand so as to cause this spring to loosen during rotation of the spool in the normal direction and to press outwardly more strongly if the brake hub intends to rotate in the opposite direction.

The brake hub is rotatably supported on the tubular part of the frame hub with the inner and outer cylindrical surfaces of the brake hub alined with the corresponding surfaces of the ring portion of the frame hub. The brake hub is held in position by a snap ring 54.

The tang 52b of the brake spring is engaged in a comb-like structure 56, which is fixed to and part of a collar 58, such that rotation of the collar 58 in the direction to unwrap the spring 52 will move the spring 52 away from the brake hub and thereby permit the brake hub to turn freely and consequently the spool which is engaged to it to turn freely. From FIG. 3, it will be observed that the actuator tab 26 is fixed to the member 58 and the actuator 24 normally is out of engagement with the tab as shown in full lines in FIG. 2. When sufficient filament 14 is used to bring the actuator 24 into engagement with tab 26 and depresses the latter (see the broken line position in FIG. 2), the member 58 is turned to unwrap the spring 52 and permit the spool to turn until the actuator disengages the tab. At that time the spring 52 again winds down on the brake hub and the ring 48 to stop the spool. The nature of the comb 56, which is usually composed of steel or other material with good wearing qualities, can be better seen in FIGS. 5 and 6. The purpose of the comb, of course, is to enable the collar and hence its actuator tab 26 to be rotationally repositioned so that it may be more conveniently located for cooperation with the actuator 24 of the tension roller 20, as previously described. Small increments of adjustment are provided by the comb such that ordinarily it is possible to find a slot which gives almost perfect adjustment to actuator position.

Claims

I claim:

1. Apparatus for controlling the feed of a filament from a spool, said apparatus having, in combination, a frame, means for supporting a spool of filament on said frame for rotation about a predetermined axis, control means through which the filament passes as it leaves said spool, said control means including a tensioning device and an actuator movable in response to the tensioning device, a ring rigid with said frame and having a first outer cylindrical surface concentric with said axis, a brake member mounted on said frame to rotate about said axis and adapted to be drivingly connected to said spool, said brake member having a hub with a second cylindrical surface axially alined with said first surface, an annular member mounted on said brake member for rotation relative to the brake member and about said axis, a helical brake spring wound around both of said surfaces with one end anchored to said frame and the other end anchored to said annular member, said spring being stressed and of a hand normally to wind down on said surfaces to hold the brake member and hence the spool against turning, and a part rigid with said annular member and engageable by said actuator when said tensioning device is in a preselected position, said part being operable upon engagement by said actuator to turn said annular member in a direction to unwind said spring whereby said brake member and said spool are free to turn, said ring and said hub having axially alined inner surfaces concentric with said axis and said outer cylindrical surfaces, a second helical spring extending across said inner surfaces with one end anchored to said frame, said second spring being of the same hand as said brake spring and stressed to wrap out against said inner surfaces whereby rotation of the frame hub and spool in the unwinding direction tends to loosen said second spring and rotation of the frame hub in the opposite direction tends to tighten said second spring against said inner surfaces and hold the frame hub and said spool against turning.

2. Apparatus for controlling the feed of a filament from a spool, said apparatus having, in combination, a frame, means for supporting a spool of filament on said frame for rotation about a predetermined axis, control means through which the filament passes as it leaves said spool, said control means including a tensioning device and an actuator movable in response to the tensioning device, a ring rigid with said frame and having a first outer cylindrical surface concentric with said axis, a brake member mounted on said frame to rotate about said axis and adapted to be drivingly connected to said spool, said brake member having a hub with a second cylindrical surface axially alined with said first surface, an annular member mounted on said brake member for rotation relative to the brake member and about said axis, a helical brake spring wound around both of said surfaces with one end anchored to said frame and the other end anchored to said annular member, said spring being stressed and of a hand normally to wind down on said surfaces to hold the brake member and hence the spool against turning, and a part rigid with said annular member and engageable by said actuator when said tensioning device is in a preselected position, said part being operable upon engagement by said actuator to turn said annular member in a direction to unwind said spring whereby said brake member and said spool are free to turn, said annular member including a series of openings angularly spaced from each other and adapted selectively to receive said other end of said brake spring thereby to position said part relative to said actuator.