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Publication numberUS3163399 A
Publication typeGrant
Publication dateDec 29, 1964
Filing dateOct 12, 1960
Priority dateOct 12, 1960
Publication numberUS 3163399 A, US 3163399A, US-A-3163399, US3163399 A, US3163399A
InventorsSkerry George A
Original AssigneeLincoln Prec Machining Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Winch hoist
US 3163399 A
Abstract  available in
Images(4)
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Claims  available in
Description  (OCR text may contain errors)

G. A. SKERRY WINCH HOIST Dec. 29, 1964 4 Sheets-Sheet 1 Filed Oct. 12, 1960 INVENTOR GEORGE A. SKERRY Dec. 29 647 INVENTOR 4 Sheet t 2 .N. et

Filed Oct. 12, 1960 Dec. 2 9, 1964 G. A. SKERRY 3,163,399

WINCH HOIST Filed Oct. 12, 1960 4 Sheets-Sheet 5 F/G. 4. FG. 5. Upslrolre dur/'ng RAI/SE Downsfrake during RA/SE FG. 7. Near fop of upstrake during LOWER (one foot/1) Stari of upsfro/rer during LOWER {ane foofl) INVENTOR GEORGE A. SKE'RRY ATTORNEY Dec. 29, 1964 G. A. SKERRY 3,l63,399

WINCH HOIST Filed Oct. 12, 1960 4 Sheets-Sheet 4 FG. 8. FG. .9. Close to bofiam of downsfroke Bottom of downsfroke LOWER (one foot/7) LOWER (one foofh) GEORGE A. SKERRY INVENTOR Star! of upsfroke LOWER {four feefh) f I I I a I e 'I ATTORNEY United States Patent O &16,399 WENCH HOIST George A. Skerry, Worcester, Mass., assignor to Lincoln Preeision Maehining Co., North Grafton, Mase., a corporation of Massaehnsetts Filed Oct. 12, 1950, Ser. No. 168364 '13 Claims. (Ci. 254-167) This invention relates to a winch hoist and more particularly to apparatus arranged to exert forces and lift leads through the medium of a cable or chain.

In the Construction of winch hoists making use of the pawl and ratchet principle, devices made in the past have provided not only for lifting a load upwardly but also for rearranging the 'pawls so thatthe load may be lowered.

While it is a relatively simple matter to arrange for moving the load upwardly, either one tooth -at a time or a plurality of teeth at one time, the lowerng operation tor more than one tooth at a time has been somewhat more difficult. It has 'been common practice to manufacture hoists of this kind capable of lowering the load by fixed plurality of teeth at any given time, usually the same number of teeth as in lifting. This large lowering increment makes it difficult to adjust the load or to lower it to a fixed position. With very heavy leads it is also somewhat dangerous to lower at a rapid rate. These and other difficulties experienced with the prior art devices have been obviated in a novel manner by the present invention.

It is, therefore', an outstanding object of the invention to provide a hoist which may be lowered in increments different from .the size, of the iucrements by which it is raised. r

Another object of this inventiou is the provision of a hoist which may be lowered at a small increment of move ment or se'lectively in multiples of that increment.

A further object of the present invention is the provii sion of a winch hoist using `a toothed ratchet and pawl in which the load may be lowered in selected sub-divisions of the number `of teeth by which it may be raised.

lt is another object of the instant invention to provide a winch-type hoist using a toothed ratchet in which the load may be lowered either one tooth at a time or in multiples of one tooth at -a time. i

It is a further object of the inventionto provide a winch hoist in which a load may be lowered in small increments or in large increments, the increments being seleetively adjustable. A

A still further object of the invention -is the provision y of a winch hoist using a ratchet and double pawls in which Afurther object of invention is the provison of a winch hoist having ratchet teeth, wherein lowering may take place in increments of more than one teeth at a time.

Another `object of the invention is the provision of a winch hoist of open Construction that may be easily in spected for wear without dis-assembly and, should repair or replacement ofparts be necessary, may be disassenbled and assembled with simple tools.

With these `and other ohjects in View, as will be apparen-t to those skilled in the art, the invention resides in the combination of parts set forth in the specification'an covered by the claims appended hereto. V

&163,%9 Patented Dec. 29, 1964 The character of the invention, however, may be best understood by reference to one of its structral forms, as illustrated bythe accompanying drawings in which:

FIG. l is -a perspective view of a winch hoist embodying the principlesof the present invention, p

FIG. 2 is a perspective exploded View of the hoist,

FIG; 3 is a eectional view of a portion ofthe invention taken along the line lil-III of FIG. 1, and

FIGS; 4, 5, 6, 7, 8, 9, and 10 :are schematic views of the important elements of the invention showing them in operative relationship. i i

Referring first to FIG. l, wherein are bes-t shown the general features of the invention, the hoist, indicated by the numeral lt?, consists of a main frame ll, through which extends a main shaft 12 on which 'are mounted an actuang pawl cam 13, a locking .pawl cam 14, an actuating handle 15, and :a selector disk 16. Also mounted on the frame is .a looking pawl 17, while an actuating pawl 13 is shown in FIG. 2 as mounted'cn the actuating handle. Swiveled to the top of the main .frame 11 is a ho-ok 19 and extendi-ng through the frame is a fiexible load-carying member such as the link chain 21 having a hook 22 at its lower end.

Referring to FIG. 2, which best shows the details of Construction of the individual elements of the invention, the main frame 11 is shown as having two sides 23 and 24joined at their upper end by a web 25 through which the shani( .of the hook 19 extends. One edge of the side 23 is formed with :an apertured boss 25 for permitting variations in the hoisting rig. I side 24 is :provided with a cylindrieal boss 26 having an axial bore 27 carrying a bronze bushing 28. The side 2.3 of the main frame 11 is also provided with'a bore and bronze bushing, but of much smaller size( A web 29 extends between the side 23 and the side 24 in the upper part of the housing and overlies an imaginary cylinder joinng the two bores. The web is somewhat semi-circular in cross sectional shape and faces downwardly to act as a shield for the elements which extend between the bores. At its upper corner the side 24 is provided with a bore 31 and a similar bore in the side 23 is aligned with it to receive ,a shaft 32 on which the locking pawl 17 is mounted.

In the description of the elements it will be assumed that the hoist is in the position shown in FIG. 1 With the hcok at the upper portion. It will be understood that, although the hoist can be used in other positions, the ex r pressions horizontaL "vertical, up, and down, and

like expressions will be used to indicate those relationshi ms with the hoist Suspended from the hook 19 and with the t load pulling downwardly .on the hook 22. Mounted in the side 24 are two pins 33' `and 34, the for-mer extending from the housing at the horizontal level of the asis of the bore 27 and slightly spaced outwardly from the outer surface of the boss 26. The .pin 34 is mounted about the same distance -from the boss 26 but is located considerably i above the horizontal level of the aXi-s of the bore 27. The

rearward end of the shaft 32 is provided with a groove 35 as the looking paw l 1'7. `This end of the shaft 32 is also provided with a groove 38 in which is snapped a lock ring 4 39. In the shaft and its -associated elements including the pawl 17 mounted in place the pawl is free to turn about the j nxis of the shaft; Mounted on the nner surfaceof the pawl which, as can be seen, is spaced 'away from the surface of the side 24 bythe Washer 37 s'mounted a spring loaded cam follower 41 which is mouited in a sheet metal housing 42 mounted on the back of'the pawl 17. and coni The outer surface of the' 3 taning a coil spring 43. The cam follower 41 is a smfll wheel-like element which is -retained within the housing by means of .a slot and shaft arrangement (not shown). The upper end of the spring is locked in place by a lug 44 extending across 'the top of the housing. A finger 45 extends from the top of the housing 42 and into the lower end of the coil spring 46 which is Suspended from the end of .a finger 47 which extends outwardly from a plate 48 fastened to the upper rear edges of the sides 23 and 24 of the main frame. The pawl 17 is somewhat elongated and is provided at one end with an aperture 49 bywhich it is mounted on the shaft 32 :and at the other end by a tooth 51 which is formed by two fiat surfaces extending at an angle of approximately 45 to one another. Mounted on the boss 26 .and pressed against the outer surface of the side 24 is `the actuating pawl cam 13 which is formed of relatively thin steel plate and which is provided with a central aperture 52. This aperture has a verticaldimension the same as the outside surfaces of the boss 26, but its horizontal dimension is considerably larger so that the cam 13 is capable :of considerable movement in a horizontal direction across the face of the cam, but not vertical movement. In addition, the cam is provided with an elongated slot 53 in which resides the pin 34 and an elongated notch 54 extending inwardly from the edge of the aperturc 52 and in which the pin 33 normally resides. The cooperation of the pins33 and 34 with the notch 54 and the slot 53, respectively, restricts the cam to horizontal motion across the face of the side 24 of the main frame. Extending outwardly from the cam in the area just above the notch 54 is a cam follower 55 which consists of a rotatable cylinder mounted on a pin. The outer periphery of thecam 13 hasa fiat horizontal edge 56 at the upper .portion and a flat horizontal edge 57 at the lower portion joined on the back side by ;a generally ci'cular edge 53. The remainder of the edge of the' cam occupied by a raised circular edge 59 and a lower edge 61 both of which are generally concentric with the axis of the bore 27 of the boss 26 and which are joined by a fairly abrupt transition surface 62. The looking pawl cam 14 is also made of 'thin steel plate and is provided with a central ape'ture 63 which is perfectly circular and which fits snugly around the outer surface of the boss 26. The outer edge of this cam is provided with a high surface 64, an intermediate surface 65, and a lo-w surface 66 The intermediate surface 65 and the low surface 66 are joined by smooth transition surface 67. The intermediate surface 65 and the high surface 64, howcver, are joined by an abrupt radial surface 68 extending inwardly from the surface 64 and a curved concave surface 69 having approximately the same curvature as the cam follower 55. The pnoportion of the periphery of the cam occupied by the various surfaces will be explained in connection with The end of the surface 64 the operation of the device. away from the radial surface 68 is occupied by a finger 71 in which is formedan aperture 72. On the other side v of the finger 7 1\the outer edge of the cam is -formed with a continuation of the high surface 64 which extends a. short distance beyond the finger. and terminates in a transition surface '73 by which it is joined to the low surface 667,' the transition surface having a somewhat s-shaped configuration providing a point at the outermost end and a concave` inner portion which joins with the low surface 66.

The main shaft 12 is provided at one end with a reduced smaller than those in the side 24,' Externallwa Washer l 75 and a bolt 76 (or similar fastener) serve to lock the .shaft in the main housing by means ofa threaded hole 4 v of the ratchet wheel is qui-te large and fits snugly within the bushing 28 in the boss 26: The immediate portion of the shaft is provided with a chain formation 73 of the usual type which will gr asp a chain tightly during the rotation of the shaft. At its outer end the shaft is provided with a groove '79 in which a snap ring 81 is intended to be placed upon assembly of all the elements.

The -actuating handle 15 h-as in its inner end a ring 83 having a bore 84 of such a size as to slide smoothly over the outer end of the shaft 12. The outer surface of the ring is provided with notches 85 (for a purpose to be described more fully hereinafter). Fastened to the handle adjacent the ring 83 is a pair of ret-aining plates 86 and 37 which extend parallel to one another away from the ctuating handle 15 and on which is adapted to be fastened a cover member 88. F astened to one edge of the cover` member 83 is a bottom 89. The retaining plates 86 and` 87, the cover member 88, and the bottom 89 fit together to form a box like structure for containing the actuating pawl .18, there being an open side facing the ring 83. The bore 91 extends through the cover member. 88 at the end opposite the bottom 89 and this bore is intended to Carry a shaft 92. One end of the shaft is provided with a groove 93 adapted to receive a snap ring 94 and at the other end is provided with a groove 95 to receive a snap ring 96. Mounted on the shaft are washers 97 and 98 followed by the actuating pawl 18 which is provided with a bore 99 whereby it may be mounted on the shaft 92 for free 'rotation.

A more detailed description of the actuating pawl 18 may be understood by referring to FIG. 3 which is a section through the retaining platcs 86 :and 87 as well as the bottom 39. Fastened to the pawl 13 in the side facing the cover member 88 is a spring-biased cam follower 101 which is generally cylindrical and which is provided with.

an axial shaft 102 'slidably received in a slot 103 formed in a sheet metal housing 104 fastened to the pawl 18. Enc'losed within the housing and pressing against the cam follower 101 is a coilspring 185. A finger 166 extends from the housing toward the bottom 89 and a peg 107 is mounted in the bottom 89 in opposition to the finger; a coil spring 108 extends between the fingerand the peg and tends to force the pawl in a direction away from the bottom 89 and :toward the ratchet wheel 77. In this figure it can be seen .that the teeth in the ratchet wheel 77 are formed vsdth smooth back surfaces 109 and the forward edge 111 of each of the ratchet teeth is formed at a slight negative angle; that is to say, the surface extends somewhat inwardly of a radial line so that, when the point 112 of the cam' 18 resides against -a tooth with the forward edge 113 of the point pressing against the forward edge 111 of the tooth, the pawl is not `free to Swing away from the ratchet wheel, particularly when the ratchet wheel is is also provided with an axial flange 115 extendirg around its outer periphery, this-fiange havingan inner surface adapted to fit tightly against the outer periphery `of the ring 83. v The outer surface` of the flange 115 is provided with smooth notches 116 to permit it to be readily grasped and turned by the operator. Located in the flange is a spring-biased ball detent 117, the ball extending inwardly of the inner surface of the ilange and coming into con-` tact with the notches 85 in the ring 83. The ball and its spring are-retained `in place by a well-known manner.

A finger lug 118 is Secured to the fiat face of the selector disk at one side of the aperture 114, while a similar lug 119 is fastened to the other side' diametrically opposite.

The lug 119, however, is provided with a finger 1-21 which extends along the outer surface of thecflange 115 in an axial direction and carries at its extreme end a pin 122 which extends axially also; upon assembly of the parts, this pin resides in the aperture 72 of the finger 71.

The assembly of the apparatus will be clear from the above description and from the drawngs, particularly FIG. 2. The main shaft 12, is mounted within the main frame 11 with the chain for'mation 78 residing between the sides 23 and 24 and under the web 29. The chair is threaded through this and is held against slippage. In other words, the ohain formation 78 is such that, if the main shaft is held against rotation, the chain cannot slip through. The looking pawl 17 is pivotally mounted on the main frarne with its spring-biased cam follower 41 extending slightly below its periphery, The aotuating pawl cam 13 is, as has been described, capable of only slght sliding motion in a horizontal direction. looking pawl cam 14, however, is oapable of being com pletely rotated about the outer surface of the bushing 25. The actuating pawl 18 rotates about its shaft 92 and oarries its spring-biased cam follower 191 extending slightly above its upper surface. The spring 163, of course, keeps the whole pawl 18 pressed inwardly toward the ratohet wheel 77, and a similar function is provided by the spring 45 in connection with the pawl 17. The looking pawl cam 14 and the selector disk 16 are locked together by the finger 122 so that the movement of the selector disk The part of the cam extends far .enough away from the shaft to contact the cam follower 41 and effeot the placement of the looking pawl 17. The looking pawL incidentally, is locked against a tooth because of the aforementioned negative angle on the face of the tooth and the point of the pawl which is jammed against it, due to the load at tempting to rotate the ratchet wheel in a olookwise direo tion. When the operator starts the downstroke of the handle 15, the aotuating pawl 13 immediately hits against the next tooth, since its' spring 108 biases it in this direction and the position of the cam 13 is so far away that it does not afieot the ,pawl 18. As soon as the actuating pawl 18 strikes the face of the tooth, further movement of the arm 15 causes rotaton of the ratohet wheel 77. It also removes the force between the looking pawl 17 and the forward face of its tooth, so that it is free to swing away from the. surface of the ratchet wheel. Its spring 46, of course, presses it toward the ratohet wheel so that it climbs over each tooth and falls into each Valley,

but does not prevent counter-clookwise rotation of the s ratchet wheel. This means, also, that, when the operator 'everses the direction of the handlel and starts it upward again, the next tooth of the ratchet wheel will autornatically be engaged by the looking pawl 17; In other causes a oorresponding movement of the cam 14 relative a to the handle 15.

The operation of the invention will now be readily understood. In this connection, reference is made' to FIGS. 4 through 10 of the drawings which show somowhat sohenatically the arrangement of the parts during operation. Assume that the winoh hoist 10 is Suspended by the hook 19 from a ceiling joistor some overhead sup-' porting member, and a load is carried by the hook 22 on the end of the chain 21; letus also assume that it s desired to lift the load by rotating the main shaft 12 and thus pass the chain 22 through the space between the ohain configuration 73 and the web 29 of the main frame, The seleotor disk is rotated counter-clookwise until it can be turned no longer. Since turning the -seleotor disk also moves the cam 14, eventually the transition surface 73 will strike the cam followerSS on the cam 13. Since the surface 73 is formed in a concave manner, it will force the cam follower to the right in FIG. 4 (if it has not already been moved to that position by pressure of the actuating pawl) and carry the entire cam in that direction, it being capable only of horizontal motion because of the engagement of the slots &and notch 54with the pins 34 and 33.

with the teeth of theratchet wheel 77. In this case it' is shown that the point engages a tooth of the ratchet.

` The pawl 18, of course, is pressed by the spring 188 toward the ratchet wheel and, as the handle 15 is moved upwardly, the 'pawl 18 rides up over each 'tooth of the ratohet wheel and falls into each oftthevalleys. As soon as the actuating arm 15 reaches'the uppermost position' desired, the operator starts its downward movement. It should be noted in connection with the upward movement that, even though the cam 14 moves along with the arm 15, because of the engagement of the spring-pressed ball detent 117 with the extreme notch 85 on the ring 83, no

In FG. 4 the left hand position of the cam 13 is shown in dotted lines and indicated by the reference numeral 123, whereas the'solid line position indicated by and brings the handle 15 'intoithe position shown in FIG.,-

8. Close to the bottom of the downstroke, the carn folf lower' 161 will leave the surface 59 of the cam 13, movie down the transition surface 62, and will then=lie closely adjacent the lower surface 61, but will not touch itg In* words, the load is held first by the looking pawl and then by the actuating pawl, the two pawls' alternating and causing the ratohet wheel 77 and'the main' shaft` 12 to. rotate in a counter-clookwise direction. 'This moves 'the chan through the main framejand causes the load to rise. i

When it is desired to lower the load, the handle 15 s held in a fixed position and the selectordisk 16 is rotated counter-olockwise until one of the numbers inscribed on" it comes opposite an indicator mark on the handle, The

number selected will determine the number of teeth which' wheel, while the looking pawl 17 does not do so. This is because the cam follower {il resideson the high surface 64 of the cam 14-. As the handle moves upwardly, however, it soon reaches the position shown in FIG. 7 and i the cam follower 4-1 has fallen past the radial surface 68 extending between the high surface 64 and the intermediate surface 65 of the cam 14. This means that the' looking pawl 17 is free to move toward the ratohet wheel 77 and does so, engaging the forward edge of the next tooth to arrive after the cam follower 41 leaves the high surface 64. The 'cam follower 101 of the pawl 18 has passed upwardly onto the high surface 59 of the cam 13, thus causngthe pawl 18 to remain outside of the outer circle of the ratchet wheel 77. No matter how much further the arm 15 is raised after this pont in the cycle,

the ratohet wheel will not be moved nor will the oondi tion of the cam be changed. The locking'carn will be holding the ratchet wheel and therload, while the cam follower 161 will merely be sliding along the surface 59 of the cam 13 with the, pawl 18 out of engagement with the ratohet wheel. The operator then reverses the movement any case, this movement causes 'the point of the pawlto press against the outer surfaoeof the ratchet wheel under the influence of. thespring 108 so that, unless, a forward f A edge of the toothis immediatelypresent the pawl 18 merely slides over the outer ends'of the teeth. It will be remembered that the'locking. paw 17 has been looked against a tooth of the ratchet wheel 77 because of the negative angle oftheir surfaces; 'lt cannot leave until 7 the pressure between the tooth and the point has been relieved. In FIG. 9 the operator continues the downstroke and the pawl 18 makes engagement with the front edge of a tooth; the load is taken over by the actuating arm and the actuating pawl`18; this relieves the locking pawl 17 of its load. When this occurs; the forces between the point' and the forward edge of the tooth are relieved and a slight movement of the ratchet wheel is sufiicient to-release the pawl` 17. Incidentally, it will be understood that the pawl remains in engagement with a given tooth despite movement of its cam follower over high portions of the cam, so long as the pawl carries the load. The release of the pawl' from the tooth takes place only because the spring 105 in the cam follower 'has a greater spring.

constant than the main pawl spring 108 and can on occasion over-ride it. At this time the cam 14 has rotated far enough so that the cam follower'41 is residing on the high portion 64 of the cam 14 so that the moment the pawl 17 is released from the ratchet tooth, the spring pressure due to the cam follower on the cam surface 64 will cause the pawl 17 to move away from the ratchet. At that point the apparatus is in the condition shown in FIG; 9 and the operator is free to begin another upward stroke of the handle. ment of the selector disk in the manner described has causedthe surface 65 of the cam 14 to press against the cam follower 55 on the cam 13 andhas caused thecam 13 to move completely over to the left'and stay there during the entire lowering stroke,` because of the extreme e length of the surface 65. That is why it is able to control the movenent of the actuating pawl 18 during the lowering cycle.

It will be understood that movement of the selector disk 16 to bring numerals 2,'3, and 4' into alignment with a marker on the handle 15 will' cause the cam 14 to lie in various positions relative to the handle and to'the actuating pawl. For instance, in FIG. 10 the selector disk has been moved to the numeral 4. This means that the end radal surface 68 of the cam' 14 resides much further around the ratchet wheel than it does in, say, FIG. 6. This means that the handle isrotated a much greater distance upwardly 'before the cam follower 41 falls off the edge of the surface 64 to permit the pawl 17 to engage the next tooth; otherwise the Operations are the same. There are two or three teeth in the letdown cycle, when thecam is positioned at points between those shown in` FIG. 6 and FIG. 10. It will be understood in connection'with FIG. 10 that the raised edge 59 of the cam 13 is located in such a position that the cam follower 101 of the pawl 18 does not' strike it until the. cam 14' has been moved a suicient distance to releasethe pawl 17' and permit it' to engagethe ratchet wheel 77. In other Words, the angle through which the arm 15 must'travel before the pawl 18 is released from the ratchet wheel is set for the largest number of teeth which are to be used drops' off the edge 59 at a point smidway between ratchet. teeth 77, because of' the engagement of the pawl 17 with its tooth. This places the pawl 18' always in the position of engaging the last tooth at the bottom of the lowering stroke. i i a It can be' seen, then', from the above description that with the present winch hoist it is possible to raise a load' It should be noted that the movefour teeth ata time' and' to `lower it at any selected rate" froni-one tooth to four teeth per st'oke. It will be understood thata rope, roller chain, metallic cable, or the' like maybe used inplace of thelink chain 21. It should'also be noted that the selector disk 16 can be rotated either fully clockwise to obtain raising and fully counter-lock wise. to obtain maximumlowering; this can be done in the dark or; `at least, without looking and there is no danger of error in direction. In other words, there is a complete stop at each end of the cycle of rotation and it is not possible to reverse the direction of load movement by continuing rotation past one end. One of the desirable features of this hoist is the fact that the chain, cable or rope may be freely released in either direction when it is entirely free of load. This is accomplished by turning the selector disk to 4-tooth lowering and setting the-'handle 15 within the range from 30 degrees above to 30 degrees below horizontal. In this position and without a load on either pawl, the spring-loaded cam followers Will force both pawls out of engagement With the ratchet and will provide free release in both directions. This function is accomplished automatically and does not require that the operator hold one pawl down manually or .place his fingers in the mechanism in any way. Free release isimportant when taking up slack when preparing to hook the chain to a load; the slightest load, however, causes one of the pawls 17 or 18 to lock securely,'

It is obvious that minor changes -may be made in the form and Construction of the invention Without departing from the material spi-rit thereof. It is not, however, desired to confine the invention to the exact form herein shown.

and described, but it is desired to include all such as properly come within the scope claimed.

The invention having been thus described, what is claimed as new and desired to secure by Letters Patent' is:

1. A winch hoist, comprising a main frame, a main shaft rotatably mounted on 'the frame, a ratchet wheel fixed to the main shaft', an actuating handle pivotally mounted, on the main shaft, a locking pawl 'pivotally mounted on the main frame in position to engage and hold the ratchet wheel, an actuating pawl pivotally mounted on the actuating handle in position to engage and rotate the ratchet wheel, and cam means having a first portion adjustably mounted and movable on and movable with the ratchet wheel for engagement with the locking pawl and a second portion mounted on the frame for en gagement with the actuating pawl, the cam means causing the ratchet wheel to be automatically rotated in equal increments selected from a plurality of substantially different increments in lowering a load.

2. A winch hoist', comprising a main frame, a main shaft rotatably mounted on the frame, a ratchet wheel fixedto the main shaft, an actuatingihandle pivotally 'mounted on the main shaft, a locking pawl pivotally rmounted on the main frame in position to engage and' adjustably mounted on and movable with the ratchet` wheel for engagenent with the locking pawl 'and having a second portion mounted on the frame for engagement with the actuating pawl, the cam means'causing the ratchet wheel to be automatically rotated in equal increments selected from' a plurality of substantially different incrementsin lowering a 1oadand means 'for movin'g the cam relative to the wheel to determine the size of the said increments. r

3. A winch hoist, comprising a main frame, a main shaftrotatably mounted on the frame, a ratchet wheel fixed to the main shaft, an actuating handle pivotally mounted on 'the main' shafit, a locking pawl pivotally mounted on the main frame in position to engage and hold the ratchet wheel, an'actuating pawl pivotally mounted on the actuating handle in position to engage and rotate the ratchet wheel, both pawls being spring-'biased toward engagement with the ratchet wheel, and `cam means havinga first portion adjustably mounted on and movable with theratchet wheel 'for ergagenent with the locking pawl and having a second portion mounted on the frame causing the ratchet' wheel to be automatically rotated in equal increments selected from a plurality of substantially p different incrementsin lowering a load.

4. A winch hoist, comprising a main frame, a main shaft rotatably mounted on the frame, a ratchet wheel fixed to the main shaft, an actuatng handle pivotally mounted on the main shaft, a looking pawl pivotally mounted on the main frane in position to engage and hold the ratchet wheel, an actuating pawl pivotally mounted on the actuating handle in position to engage and rotate the ratchet wheel, each pawl having a cam follower mounted thereon with a spring interposed between each pawl and its cam follower, and cam means having a first portion adjustably mounted on and movable with the ratchet wheel for'engagement with the locking pawl and having a second portion mounted on the frame for engagement with the actuating pawl, the cam means causing the ratchet wheel to be automatically rotated in equal increments selected from a plurality of substantially different increments in lowering a load.

5. A winch hoist, comprising a main frame, a main shafit rotatably mounted on the fraine, a ratchet wheel fixed to the main shaft, an actuating handle pivotally mounted on the main shaft, a lockingpawl pivotally mounted on the main frame in position to engage and hold the ratchet wheel, an actuating pawl pivotally mounted on the actuating handle in position to engage and rotate the ratchet wheel, a cam adjustably mounted adja cent the Iatchet wheel engaging the locking pawl on occasion and causing the ratchet wheel to be rotated automatically in selected increments in lowering the load, and means for adjusting the cam relative to the ratchet whee to determine the size of the said inc'ements.

6. A winch hoist, comprising a main frame, a main shaft rotatably mounted on the frame, a ratchet wheel fixed :to the main shaft, an actuating handle pivotally mounted on the main shaft, a looking pawl pivotally mounted on the main frame in position to engage and hold the ratchet wheel, an actuating'pawl pivotally mounted on the actuating handle in position to engage and rotate the ratchet wheel, a cam adjustably mounted adjacent the ratchet wheel engaging the actuating pawl on occasion and causing the ratchet wheel ..to be rotated automatically in selected increments in lowering the load, and means for adjusting the cam relative to the ratchet wheel to deternine the size of the said increments.

7. A winch hoist, comprising a main frame, a main shaft rotatably mounted on the frame, a Iatchet wheel fixed to the main shaft, an actuating handle pivotally mounted on the main shaft, a locking pawl' pivotally mounted on the main frame in position to engage and hold the ratchet wheel, an actuating pawl pivotally mounted on the actuating handle in position to engage and rotate the ratchet wheel, each pawl having a cam follower mounted thereon with a spring intei'posed between each pawl inits cam follower, cam means engaged on occasion by the cam followers causing the ratchet wheel to be rotated automatically in selected increments in lowering the load, and means for adjusting the cam means relative to the ratchet wheel to determine the size of the said increments. r

8. A winch hoist, comprising a main frame, a main shaft rotatably mounted on the frame, a ratchet wheel,

fixed to the main shaft, an actuating handle pivotally mounted on the main shaft, a locking pawl pivotally mounted on the main frame in position to engage and hold the ratchet wheel, an actuating pawl pivotally mounted on the actuating handle in position to engage and rotate the ratchet wheel, both pawls being spring-biased toward engagement with the ratchet wheel, and a cam adjustably mounted adjacent the ratchet wheel engaging the `locking pawl on occasion and causing the ratchet wheel to be rotated automatically in equal increments selected from a plurality of substantially different increments in lowering a load.

9. A winch host, comprising a main frame, a main shaft rot atably mounted on theframe, a ratchet wheel fixed to the main shaft, an actuating handle pivotally mounted on the main shaft, a locking pawl pivotally mounted on the main treme in position to engage and hold the ratchet wheel, an actuating pawl pivotally mounted on the actuating handle in position to engage and rotate the r'atchet wheel, both pawls being springbiased toward engagement with the ratchet wheel, and a cam adjustably mounted adjacent the ratchet wheel engaging the actuating pawl on occasion and causing the ratchet wheel to be rotated automatically in equal increments selected from a plurality of substantially different increments in lowerng a load.

10. A winch hoist, comprising a main frarne, a main shaft rotatably mounted on the rame, a ratchet wheel fixed to the main shaft, an actuating handle pivotally iounted on themain shaft, a locking pawl pivotally mounted on the main frame in position to engage and hold the ratchet wheel, an actuating pawl pivotally mounted on the actnating handle in position to engage and rotate the ratchet wheel, both pawls being springbiased toward engagement With the ratchet wheel, each v 'pawl having a cam follower mounted thereon With a spring interposed between each pawl and its cam followei', andcam means having a first portion adjustably mounted on andmovable with the ratchet wheel for engageinent with the locking pawl and having a second portion mounted on the frane for engagement with the actuating pawl, the cam means caused the ratohet wheel to be automatically rotated in 'equal increments selected from a plurality of substantially diiterent increments in lowering the load. I

ll. A winch hoist, comprising a main frame, a main shaft rotatably mounted on the frame, a ratchetwheel fixed to the main shaft, an actuating handle pivo-tally mounted ,on the main shaft, a locking pawl pivotally mounted on the main frame in position to engage and hold the ratchet wheel, an actuating pawl pivotally mounted onthe actuating handle in position to engage and rotate the ratchet wheel, a cam adjustably mounted adjacent the ratchet wheel and engaging the looking pawl on occasion, a cam engaging the actuating pawl, these cams causing the ratchet wheel to be rotated automatically in equal increments selected from a plurality of substantially diiierent increments in lowe'ing a load.

12. A winch hoist, comprising a main frame, a main shaft rotatably mounted on the frame a ratchet wheel fixed to the main shaft, an actuating handle pivotally mounted on the main shaft, a looking pawl pivotally mounted on the main franie in position to engage and hold the ratchet wheel, an actuating pawl pivotally mounted on the actuating handle in position to engage and rotate theratchet wheel, each pawl having a cam follower mounted thereon With a' spring interposed be tween each pawland its cam follower, a' camengagi g the locking pawl on occasion, a cam engaging the actu'- ating pawl onoccasion, these Cams causing the ratchet wheel to be rotated automatically in equal increments. i selected from a` plurality of substantially different increnents in lowering a load. c

13. A winch hoist, comprising a main frame, a main shaft rotatahlymounted on the frame, -a ratchet wheel fixed to the main shaft, an actuating handle pivotally` mounted on the main shaft, a looking .pawl 'pvotally mounted on the main frame in position to engage and hold the ratchet wheel, an actuating pawl pivotally mounted on 'the actuating handle in position to engage and rotate the ratchet wheel, a cam adjustably mounted adjacent the ratchet wheel engaging the looking pawl on occasion, a cam engaging the actuating pawl on occasion, these cans causing the ratchet wheel to be rotated automatically in selected increments in lowering a load, and

fixed to the main shaft, an actuatinghandle pivotally mounted' on the main shaft, a locking pawl pivotally mounted on the main frame in position to engage and hold the ratchet wheel, an actuating pawl pivotally mounted on the actuating handle in position to engage and rotate the ratchet wheel, each pawl having a cam follower mounted thereon with a spring interposed between each pawl and its cam follower, a cam engaging the cam follower of the' locking pawl on occasion, a cam engaging the cam follower of the actuating pawl on occasion, these cams causing the ratchet wheel to be rotated automatically in selected incremen'ts in lowering the load, and means for adjusting the cams relative to the ratchet wheel to determine the size of the said increments.

15. A winch host, comprising a main frame, a main shaft rotatably mounted on the frarne, a ratchet wheel fixed .to the main shaft, an actuating handle pivotally mounted on the main shaft, a locking pawl pivotally mounted on the main frame in position to engage and hold the ratchet wheel, an actuating pawl pivotally mounted on the actuating handle in position to engage and rotate the ratchet wheel, both pawls being springbiased toward engagement with the ratchet wheel, each pawl having a cam follower mounted thereon with a spring interposed between each pawl and its cam followera.cam engaging the cam follower of the looking paWl on occasion, a camtengaging the cam follower of the actuatng pawl on occasion, these cams causing the ratchet wheel to be 'otated automatically in selected increments in lowering a load, and means for adjusting the cam relative to the ratchet wheel to determine the size of the said increments.

16. A winch host, comprising a main frame,ta main shaft rotatably mounted on the frame, a ratchet wheel fixed to the main shaft, the ratchet wheel having teeth with forward edges with negative rake, an actuating handle pivotally mounted on the main shaft for movement through an -upstroke and a downstroke, a locking pawl pivotally mounted on the main frame in position to engage and hold the ratchet wheel as the handle moves at the end of an upstroke, an actuating pawl pivotally mounted on the actuating handle in position to engage and rotate the ratchet wheel as the handle moves at the end of a downstroke, both pzwls being springbiased toward engagement wtih the ratchet wheel, each pawl having a point adapted to engage the forward edges of the teeth of the ratchet wheel and having a cam follower mounted thereon With a spring interposed between each pawl and its cam follower, an actuating pawl cam mounted on the main frame `so as` to be capable only of slight linear sliding motion thereacross and having a high edge which contacts the cam follower of the actuating pawl and .renders the actuating pawlneffective to engage the ratchet wheel when the actuatingjhandle is moved to the end of an upstroke while lowering a load,

a locking pawl cam mounted on the main fran ie for rotation and being fastened to the actuating handle for rotation therewjth, the locking pawl cam having a high surface which engages the cam follower of the locking pawl to render the looking pawl inefiective to engage the ratchet wheel during the beginning of an upstroke of the actuating handle while lowering a load, means adapted to connect 1 2 the tWocamswhile lifting a'load' to render both pawl cams inefiective to contact either cam follower, the cams causing the ratchet wheel to berotated automatically in:

selected increments in' lowering a load, and means for adjusting the angular relationship'between the handle and the locking pawl cam to select the size of the said increments.

17. A winch host, comprsing a main frame, a main shaft rotatably mounted on the' frame; a ratchet wheel rotatable with the main shaf t, an actuatinghanclle mounted for pivotal action, a spring-biased locking pawl pivotally mounted in position to engage and hold the ratchet wheel, a spring-biased actuating pawl: pivotally mounted" on the actuating handle in position to engage and rotate the ratchet wheel, each pawl: having a cam follower` mounted thereon with a spring located between each pawl'.

and its cam follower, a' cam lockedfor rotation with the handle andengagingthe cam follower of the looking pawl' on occasion, a cam engaging the cam follower of the actuating pawl on occasion, the cams causing the ratchet' wheel to be rotated automatically in seiectcd'increments in lowering the load, .and means for adjusting the angular relationship between the handle andthe locking' pawl cam for selecting the size of'the said 'increments i 18. A winch host, comprising a main frame, a main shaft rotatably mounted on the frame, a ratchet wheel' fixed on the main shaft,` an actuating handle pivotallymounted on the main shaft, a locking pawl pivotally mounted on the main frame in position to engage and hold theratchetwh'eel, an actuating pawl pivotally mounted on the actuating handle in position to engage androtate the ratchet wheel, means alternately releasing the pawls to rotate the ratchet wheel in raising the load so that a plurality of teeth can pass a given point, and cam` means having a first portion adjustably mounted on and movable with the ratchet wheel for engagement with the locking pawl and having a second portion mounted on the frame for engagement with the actuatingpawl-,the cam means causing the ratchet wheel' to be' automatically rotated in equal increments selected from a plurality of substantially different increme'nts in lowering a load, the first pontion of the cam means being adjustable relative to the ratchet wheel so* that a portion of each pawl engages the cam means and the pawls opera-te 'alternately to engage the ratchet wheel in lowering a load 'in such a manner that a number of 'teeth in the range from one to' the said pluralit y of teethjpassa given point.

References Cited'in the'file of 'this patent UNITED STATES PATENTS Moseley et al'. Apr. 4, 1961

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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3672637 *Jan 14, 1970Jun 27, 1972Duff Norton CoRatchet lever drum puller
US3765652 *Apr 9, 1971Oct 16, 1973Emerson Electric CoCable hoist
US3985342 *Jun 23, 1975Oct 12, 1976Denman Stephen APortable hoist
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US5316266 *Apr 21, 1992May 31, 1994Chou An ChuanStrap extender and tensioning system
US6491195Aug 23, 2000Dec 10, 2002Mclemore John D.Carrier device
US7559533Jan 16, 2007Jul 14, 2009Gorbel, Inc.Lift actuator
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Classifications
U.S. Classification254/369, 254/376, 74/155, 254/380, 254/372
International ClassificationB66D3/14, B66D3/00
Cooperative ClassificationB66D3/14
European ClassificationB66D3/14