US2961217A - Winch or hoist brake - Google Patents

Description

Nov. 22, 1960 c. R. SAGGI-HN; 2,961,217

WINCH 0R HoIsT BRAKE Filed July 28, 195e Arran/viv United States WINCH on Holsr BRAKE Columbus R. Sacchini, Willoughby, Ohio, assignor to CurtissWrigl1t Corporation, a corporation of Delaware Filed `luly 28, 1958, Ser. No. 751,321

7 Claims. (Cl. 254-186) This invention relates to a load hauling winch, windlass or hoist mechanism, particularly adapted for manual operation as in loading boats or other heavy or unwieldy objects onto trailers, platforms and the like and safely lowering such boats or objects with or without assistance of skids or ramps. One object hereof is to simplify the construction while providing Safety of operation of portable or relatively light weight winch mechanisms such as are usually operated by cranks through suitable gearing or equivalent mechanical advantage means connected to cable reels or windlass drums for load-connected cables or ropes.

Other objects include provision of a winch wherein the usual ratchet and the pawl type releasable load holding or restraining mechanisms are replaced by a simple readily releaseable one-way locking coil brake operable very powerfully to hold heavy loads and prevent accidental lowering thereof and to enable safe incremental or steady controlled cable-pay-out operations for lowering; and provision of a winch mechanism according to the foregoing wherein, after complete paying out of the rope or cable from the reel or windlass drum, the mechanism cannot be operated in a reverse or improper direction or such as will defeat automatic one-way locking action of the coil brake and convert the crank into a Source of injury to the operator in case he releases it under load.

Objects and novel features of the invention not indicated in the above will become apparent from the following description of the preferred forms as shown in the drawing. The essential characteristics are summarized in the claims.

In the drawing Fig. l is an assembly partially sectional View of one form of winch mechanism (A) hereof. Fig. 2 is a detail or fragmentary view taken as indicated by the line 2-2 on Fig. 1. Fig. 2A is a fragmentary detail sectional view of a push rod device according to Fig. 2.

Fig. 3 is an assembly view similar to Fig. 1 showing a modied form (B) of winch hereof. Fig. 4 is a relatively enlarged central sectional view of the brake and release mechanism according to Fig. 3, taken as indicated by the line 4 4 on Fig. 3. Fig. 5 is a sectional detail view taken along the line 5-5 on Fig. 4.

Winch assembly A Referring to winch mechanism assembly A, Fig. 1, the frame or base 1, as somewhat incompletely shown, comprises a single piece channel-shaped member having a web portion 2 and paired spaced apart ange portions 3 'and 4, the web portion having suitable provision (e.g. slots 5 and 6) for receiving fasteners, not shown, whereby the winch may be secured to a trailer framework or any other suitable support. The flange portions 3 and 4 of frame 1 rotatably carry respective end portions of a drive or input shaft 8 for operation by a crank 9. The crank is preferably readily detachable from the shaft 8 to discourage unauthorized tampering with the winch. The reel or windlass drum 10 is freely rotatable on a supporting axle 11 xedly supported by the ange portions 3 and 4 of the frame 1. One end of the drive or input shaft 8 has rigid therewith a driving gear 12 constantly meshing with a larger gear 14 secured as shown to one of a pair of anges 15, 15 of the reel or drum 10. The load-connected rope or cable 16 is secured to the drum as on ange 15 thereof as by a suitable detachable clamp 17.

In order to prevent accidental or unintended load-lowering rotation of the drive shaft 8 (direction indicated by arrow a on Fig. l) while not interfering in any way with controlled lowering and/ or load raising operation by the crank (raising direction per arrow b), the no-back safety coil brake mechanism generally indicated 20 is yassociated with one end of the drive shaft 8. Mechanism 20, as shown, includes a generally cylindrical housing 21 secured as by a series of rivets, one shown at 22, to the flange portion 4 of frame 1 around the rightwardly projecting end portion 23 of shaft 8, coaxial therewith. An inner tubular flange portion 21 of housing 21 forms a rightward supporting bearing for the drive shaft. A brake drum portion 24 of the drive shaft (or drum member secured to it) is shown as enveloped by a helical one-way frictionally locking coil spring 25 within the housing 21. A fixed end coil of the spring 25, which may comprise an eye formation 26 of the spring stock, is secured to the frame portion 4 as by one of the rivets 22. All the coils of the spring 25 are elastically preloaded on or in interference fitting relationship to the drum portion 24 of the drive shaft. For reeling in operation in the arrow-indicated direction b Fig. l, the spring is right hand wound. The free end coil of spring 25 or the end opposite the anchor loop or eyelet 26 is extended through an opening 3l) in the housing 21 to provide a brake release or control arm 23 in a position readily accessible to the operator of the crank 9. Lifting of the control arm 28 (upwardly in reference to the plane of the paper) from a position in which the spring is fully seated on drum 24 releases the coil spring 25 from its self energized locking condition so that the drive shaft 8 can be freely turned in either direction.

Referring to Fig. 2 the opening 30 in the wall of the housing 21 has a lower portion 30a in which the control arm or arm portion 2S of the spring 25 is received freely when the spring is in one-way locking relationship to the drum surface 24, the position of the arm then being as at 28a, Fig. 2. A shoulder or ledge surface portion 30b of the wall of the housing operates as a detent to retain the arm portion 28 of the spring in the position 28b thereof when the spring 25 has been released from locking contact with the drum surface 24. An operating handle 29, Fig. 1, may be provided on the free end of the control arm 28. If the arm 28 is moved leftwardly from its indicated position 28b, Fig. 2, it will spring down through torsion action of the coiled spring into the position 28a. In moving to the position 28a the arm 28 should be completely free from frictional contact with the housing 21 so as not to be restrained in a position partially to deenergize the Spring 25 and reduce its capacity for automatically blocking the lowering movement of the load.

In order that the operator, when the cable is completely payed out, will not be able to turn the drive shaft 8 in the wrong direction, i.e. so as to wind the rope or cable 16 on the reel 1t) reversely of the indicated direction (in which case the lockin mechanism 20 would not function to restrain lowering movement) the crank as shown has one or more inclined slots 32 open inwardly toward the winch for engagement with end portions of a cross pin 33 in the shaft extension 23. Thereby obviously the operator, via the crank 9, can forcibly turn the shaft 8 only in the direction indicated b. Additionally, in order to insure that when a winding operation of the crank commences, the control arm 28 will not inadvertently be allowed to remain in the brake-spring-releasing or detained position Winch assembly B Referring to winch B as shown in Figs. 3 through 5, the 'general arrangement of winch apparatus is the same as in Fig. 1 and the corresponding parts insofar as similar have the same numbers or reference characters, sometimes primed. The reeling-in direction, arrow b, is the same as in Fig. l, hence the helical locking spring 35, Fig. 4, is also right hand wound. The control arm or free coil end extension 36 of spring 35 projects through a slot 37 in spring brake drum housing 21". In the one-way locking position of the spring the arm 36 occupies a lowered position (not shown) in slot 37. At the upper end of the slot 37 (Figsf3 and 5 the wall of the casing 21 is diverted or pressed outwardly `as at 38 to provide a circumferentially facing detent shoulder 39 for a. latch assembly indicated generally at 4G and which is operated by the crank 9 to release the spring 35 from its expanded or non locking position in case it was in that position when the crank was applied to the drive shaft.

Latch mechanism 40, as shown, includes a slide plate 41 having a yoke or slotted portion 42 which slidably embraces a peripheral groove 44 (Fig. 4) in the drive shaft 8 for movement parallel to the end wall portion of the housing 21. Additionally, the slide plate 41 has a ange portion 45 which is apertured slidably to receive the arm portion 36 of the braking spring 35. The flange 45 abuts the detent shoulder 39, Fig. 5, to hold the brake spring in drum releasing position.

For assembly purposes the slide plate 41 is sprung over vthe outer end portion 23 of shaft 8' into the peripheral groove 44. To permit this the stamping from which slide plate 41 is made can be lanced through or slit as at 46 Fig. 5, so that the two sides of the plate 41 embracing the shaft 8' comprise spring arms.

The latching tlange 45 of the slide plate 41 is normally urged toward theaxis of the drive shaft 8 as shown particularly in Fig. 5 wherein a light coil spring 47 around the spring arm portion 36 rests on the flange 45 and is maintained in compression as by a suitable knob 48 tightly securedto the outer end of the spring arm portion 36. A casing 49 for the coil spring 47, supporting a cap or knob 51, is suitably secured at 50 as by solder to the flange 45. IIn order to release the latching detent assembly 40 the operator grasps the knob 51 and moves the latching ange -45 radially of the drive shaft 8 out of engagement with the detent abutment 39, whereupon the torsion of the braking spring 35 moves the pate 41, etc. counterclockwise (Fig. 5) into whatever position the brake spring 35 requires in order to fully seat its coils on the drum surface 24.

The crank operated safety unlatching connection between the crank 9 and the slide plate assembly 40 includes circular camming surfaces of arcuate form on an 'outstanding flange portion 54 of the slide plate 41. The crank 9' has a non circular opening 9 Fig. 3 tting over Ythe drive shaft extension 23', and when the crank is in Yfully'seat'ed position on the shaft extension the pin portion 55 of the crank lies at one side or the other of the slide plate 41. When the' crank is in its normal operating position on the shaft extension 23', or as diagrammatcally shown in Fig. 4, the pin 55 is as diagrammatically indicated iu Fig. 5 or at one side or to other of slide plate 41. lf the latch assembly has been left in the brake re leasing or Fig. 5 illustrated position then the pin 55 on Ithe crank, after some idle motion of the crank less than a full turn thereof, engages the arcuate cam surface on 'the ange portion 54 to lift the latching flange 45 out of engagement with detent 'formation 38 and allow the brak- 4 ing spring to reseat itself before any reeling-in operation can be accomplished by the winch mechanism.

It will be apparent from the above that, with either herein described form of winch mechanism, the load can be gradually lowered at any desired speed by manipulation of the handle devices attached to the control arms (28 or 36) of the helical brake springs to move the control arms toward the associated latch or detent abutments (30!) or 39); and that, by positioning the control arms in detent-'engaged condition, the ropes or cables attached to the winch reels can be freely stripped or unspooled. Also, it will be apparent that, with either disclosed form of mechanism, safety release of the brake to its automatic one-way-locking position is compelled as a condition of any manual operation of thel crank to lift or haul in the load.

I claim:

l. ln a winch, a cable reel, a drive shaft. geared to the reel, "a 'one-way acting self energizing friction brake. on the drive shaft, manually operable means connected to release Vthe brake, said means having a detent capable of holding said means in brake-releasing position, an operating crank detachably connected with the drive shaft, and means on the crank operating to effect release of said'rnanually Voperable means from restraint by its detent as a condition of operation of the drive shaft by the crank.

2. A winch comprising a frame, a cable reel rotatably supported by the frame, a drive shaft rotatably supported by the frame and having a step-down gear connection with the reel, a brake drum rigid with the shaft, a helical friction coil spring secured at one end thereof tothe frame and having coils elastically preloaded on the drum tolock the drum against rotation in one direction, a spring release arm connected to the opposite end of the spring, and a latch abutment on the frame disposed for operative engagementf'oy or with the release arm to hold the spring out of locking contact with the drum.

3. A winch according to claim 2, wherein the spring release arm extends radially of the axis of the spring, a housing around the spring fixed to the .frame and having an arcuate slot through which the release arm extends, a catch device slidably supported conjointly by the drive shaft and release arm for movement transversely of the shaft and spring, the catch device being spring loaded against a portion of the release arm for movement of the catch device toward the axis of the shaft, said latch abutment being supported by the housing fcrfoperative engagement with the release arm via Vthe catch device, an operating crank for the drive shaft, a cam on the catch device, and a pin on the crank engageable with the cam as a function of turning of the crank and operating to release the catch device for enabling return of the spring to drum locking position.

4. ln a winch, a frame, a cable reel and a drive shaft on the frame, the shaft vbeing connected to the reel by step-down gearing, a brake drum on the shaft, a self energizing helical coil Ybrake member normally in frictional one-way locking engagement with the drum to prevent rotation of the shaft in one direction only, manually operable means connected to the coil brake member to release it from locking engagement with the drum, a retaining shoulder on Vthe frame for holding said means in brake releasing position, a crank detachably connected with the shaft, and a device on the crank disposed in position to release said means from engagement with the re- 'taining shoulder when the crank is in drive-shaft-operating position.

5; The winch according to claim 4, wherein said device Vis rendered operative to restore the coil brake member to locking position on said drum as a function of turning the crank in one direction only.

6. The winch according to claim 4, whereinthe detachable lconnection between the 'crank and drive vshaft in- 2,961,217 5 cludes cam means operating as a function of turning References Cited in the le of this patent the crank in one direction only when associated with the drive shaft to cause said device to restore the coil brake UNITED STATES PATENTS as a function of turning of the crank. 10 59,717 Sweden Oct. 6, 1919

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