US2287551A - Free chain hoist-full automatic and semiautomatic - Google Patents

Description

June 23,1942. F. w. coFFlNG j FREE CHA IN HO IS T-FULL AUTOMATI C AND S EMI -AUlIOMAT I C 2 Sheets-Sheet 1 Filed Nov. 19, 1938 Patented June 23, 1942 UNiTED STATES FREE CHAIN .HoI's'r-FULL AUioM'A'rre" AND sEMIAUToMA-mo rFredrickW. Cofling, Danville, Ill.-v Appiicanon November 19, 1938,A serial N o. 241,303

(o1. er-:1.67)

1-6 Claims;

This invention relates to a ratchet hoist of the general character illustrated in my prior Patent No. 1,937,331 dated November 28, 1933.r

The present invention is directed to a full or semi-automatic ratchet hoist. The invention provides. that the operator of the hoist may obtain load lowering without the necessity of utilizing theI lever 44 shown in Figs. 2, 3, V 7 and 8 of said patent.

The hoists `in the present invention are similar to the hoist shown in the patent mentioned, except that the reversing ring structure shown-in said patent', is not required herein. This constitutes one major simplification.

Otherfobjects and features of the invention will be set forth more fully'herenaiterl The full nature' of the invention willbe understood from the accompanying drawings andthe following description and'claims. Y

In the drawings Fig. 1 is'a" plan View looking at the two-piece hoist housing and particularly the rear or back face of the'h'andle' structure.

Fig. 2 is a View looking toward the opposite side of the housing and the same 'housing'part Fig. 3 is a View looking toward the' inside' of the handle associated.particularlywith the hoist body.

Fig. 4 is alongitudinal sectional View through the same portion',.the dotted'lin'es illustrating 'the association with the hoist proper.

Fig. 5 is aplan view' similarto Fig.' 1 andof a semi-automaticembodiment of the"invention,`

Fig. 6 is a view' similar to Fig. Z'ando the semi-automatic'form ofthe invention.

Fig. '7 is a ViewV similar to Fig. 4 Aand o' Athe handle in` thesemi-autoniatio form of the invention.

Fig. 8 is an endy elevation of a portion of-'a hoistvemb'odying the semi-automatic form ofthe invention.

In View of the complete description of a hoist of this general character in the before mentioned patent, much oiA the description of the instant invention so Vfar as certain of the parts are'con-L cerned, willbe omitted. Refer-enc@ however, is

GFF-ice in the housing is a chain channel having two communicating branches I2 and I3', and positioneditherein is the sprocket type load. chain I4; the Vlinks* oftwhich engage sprocket I5 carriedby I6 also' supports', andv preferably has integral therewith; ratchet'formationi'l'. y y

Within the housing ,IIIis a chamber I8' and pivota'lly supported; in saidr chamber asby shaft I9`isavsprocketldcking'dog or pawlZ". IA spring 2|, suitably anchored'atoneendas'at 2'?, is^con n'ect'edto the dog or pawturging it into sprocket engagement. y

.As' the sprocket isrotat'e'd clockwise-#seeing l-'for'load elevation; each successive' tooth of the sprocket engages the dog Z'fand scams* it: into the dotted line positionJ shown.' When elevationalmovernent has ceased, .thedog '2 Ilz holdsV the sprocket I5 against reverse rotation, therebyhol'ding the' loa'd';v Thus; it ma'yjbe'said thechaincan freely advance inthe' loa'd elevating direction;

A 'handle 'structure' is shown-.in Fig. V1 and'is somewhat similar tothe"ha` ndle@structure shown in Figs. 4, 5 and 6 of the patent-before mentioned, and inf general it may 'besaidthefoperation fof' the handle structure'is the' same; except as hereinafter 'pointed out.

The'h'andle 'structure includes at socket type en'd 30, see Figs. 3 and /4fwhich formsa chain-ber Sibfor enclosing ratchetII`show1riirFig. 2." The housing' expbsed end" of theshaftiiiis `received by -th'ecoaxia-l vhub portion V31 lof the handle and it is by thismeans that the handle' is swivelably mounted. Suitable handle securing means a is associated with thev shaft' atthe end ofjthe Vhuh por'tion'l, such asfor example; that'illustrated in Fig. l of4 the before mentioned patent.'- Any other suitable form oi connectioirfmaybe employed, however.A -Y

T e-'arin ortior l32 of the `'handle -is suitably ribbed as ait-3? for re-enforcemeiitan'dfth'e 'end thereof'. maybe apertured as at `lisor thatr airope can be attachedfthereto 'for hoist actuation; whenever the handleis vpositioned ahem-:fthe operator.

made to said patent for a general description' and understanding of the construction fand operation of the'hoist's embodyingthe instant invention.

In Figs. 1 to 4 of the' drawings'there is illustrated a full-automatic embodiment of the invention'. Therein I0 indicates onepart of atwopiece complementary housing structure, the '.two partsbeing' suitablyfsecured together by suitable means as'sociate'diwith the openings' II. Formed .This aperture` also' is provided to ,receive Y a support for suspendingly supporting the hoist when not in use as on a snaphook attached to a linemansbelt-Q f The handle onits rearfaee if provided Vwith two anges 35 which form' a4 channel 'and positioned' in said vclis'innel is an actuating rod 36. This actuating rodat its 'end adjacent the aperture l34`is' oiset laterallyaas "at 3l and extends throughy an opening "38 "formed inj a lever member 39 pivotally supported at 40 -betWeen ears* 4l formed integral with the handle. The exposed end of the lever is enlarged laterally as indicated at |42 and lies alongside of the handle. Thumb pressure upon the enlarged portion or thumb pieces causes the rod 36 to move toward the ratchet I1. It will be noted that the rod 36 is offset as at 36a so that thumb actuation of the lever 39 tilts pawl 49 into released position, as shown by dotted line in Fig. 3 after force of spring 4'I is taken up. This offset portion is comparable to the offsetting in the rod 36 shown most clearly in Fig. 4 of said patent.

The handle structure, similar to that illustrated more especially in Fig. 9 of the before mentioned patent, is provided with an angular closure plate 42 having the lateral portion 43 notched as at 44 to permit the passage of the rod 36. The free end of the rod. 36 extends into the chamber 36b of the portion 30-see Fig. 4. This rod 36 has its free end turned laterally as at 45, see Figs. 3 and 4. This rod 36 extends through an aperture 46 in a relatively stiff spring member 4T, see Fig. 3, suitably secured as at 48 to the ratchet engaging pawl 49, the latter being pivotally supported in the handle as at 56. A spring 5I at one end is anchored to the handle structure as at 52 and at its opposite end is secured to the relatively stiff spring member 4'I.

'Ihe pawl 49 is suitably relieved as at 49#1 and has a certain draft 49h. It carries a pin 53. Extending into the chamber 3|!b is a stop pin 54 for limiting pawl movement. The pawl 49 constitutes the operating connection between the handle and the ratchet. When this pawl engages the ratchet and is lockingly associated therewith, clockwise rotation of the handle-see Fig. 3- causes rotational movement of the ratchet I'I, shaft I6 and sprocket I5 and consequently load elevation. When through actuation of rod 36, after the ratchet and pawl are suciently separated to free same from the draft lock I'I-49b, the pawl 49 is tilted counter-clockwise into the dotted line position shown in Fig. 3 and the pawl is thereupon released from the ratchet I'I.

The cover plate 42 provides a bearing or guide 55, see Fig. 3, for a plunger 56 having a chamfered or beveled face 51 at its chamber enclosed end, see Figs. 3 and 4. This plunger is provided with a collar portion 58 and a spring 59 concentric therewith normally constrains the plunger into its projected position, the same being shown in Fig. 4 by the full lines. The plunger 56 extends through the opening 6U in the handle 32 and on its exposed end mounts a finger piece 6|. The latter may be suitably apertured as at 62. Suitably secured to the handle 32 and extending upwardly therefrom is a pin 63 normally receivable by the aperture 62.

When the plunger 56 is pulled outwardly so that the rear face of the finger engageable portion 6I lies beyond the end of the pin 63, it may be turned so as to ride upon the end of the pin 63, s ee Fig. 4, and in this position the plunger 56 is maintained in the retracted position.

Referring to Fig. l, it will be remembered the sprocket locking pawl is pivotally supported as at I9. This shaft I9 projects through an opening |63 in the housing I0, see Fig. l, and its ex' posed end |64, see Fig. 2, is suitably reduced and provided with a cam or cut-away formation 64. Projecting laterally and oppositely from the reduction 64 and bearing or hub 69 and in spaced relation to the face of said housing I9, is a cam rfaced member 65.

Pivotally supported at 66 on the housing I9, see Fig. 2, is an arcuate or quadrant shaped member or pawl 61 normally constrained by a spring 3, having its mid-portion coiled about the pivot 66. Said pawl 61 normally engages the bearing or hub 69. One end of the spring is associated with the anchorage or pin on said arcuate member 61. The other end of the spring bears upon the bearing or hub 69 as shown in Fig. 2. Pawl 6'I has a cooperating end 'II adjacent the cam portion 64. Chamber 36a protects the aforesaid.

The foregoing constitutes the construction of the parts embodied within the full-automatic form of the invention.

The operation of said parte is as follows:

As the handle is rotated clockwise-see Fig. 3 the shaft I6, ratchet I'I and sprocket I5 rotate for load elevation. In this movement, the sprocket teeth successively force the sprocket locking pawl 20 from full line position into dotted line position, see Fig. 1. At the end of the arcuate movement of the handle, the sprocket locking pawl 26 takes the load and holds the sprocket I5 against load lowering. The handle can then be reversely rotated and in this movement pawl 4S ratchets on teeth ITI. At the end of this return movement the ratchet pawl 49 engages the ratchet and a reverse or clockwise movement of the handle again is then effective for continued load elevation. This is the elevating action of the hoist. For a more complete description thereof, reference is had to the before mentioned patent.

For load lowering a somewhat reverse cycle is employed, to-wit, as the handle is oscillated to and fro for load lowering locking pawl 29, see Fig. 1, and ratchet pawl 49, see Fig. 3, alternately engage the sprocket and the ratchet, respectively, and the weight of the load pulling on the chain is the power applied to the sprocket and the .shaft I6, so that said shaft, sprocket and ratchet are permitted to rotate in a reverse direction from that of load elevating, to-wit, load lowering, and step by step or tooth by tooth. In this operation and since the reversing ring structure of the patent before mentioned is not embodied herein, the parts mutually cooperate in the general manner indicated substantially as follows:

The pin 53 carried by the ratchet pawl 49, see Fig. 3, passes between the bearing or hub 69 and the relieved portion 64 of the shaft |64, and upon sufficient clockwise rotation, as in Fig. 2, engages the face 'II of the pawl 61. Further arcuate clockwise movement of the pin tilts said pawl 6'! in opposition to its constraint from the full line position-see Fig. 2-to the dotted line position.. Outward movement of pawl 61 is limited by stop |61.

In this same general direction of handle movement (clockwise), the plunger 56, see Fig. 4, engages the cam portion 65-see Fig. 2-of the lateral enlargement of the shaft |64 and rocks the shaft I9 so as to move the pawl 20 from the full line to the dotted line position-see Fig. 1. This permits pawl 20 to pass over a sprocket tooth as the sprocket and handle continue rotation in load lowering movement. This plunger 56 then releases member 65. Pawl 20 urged by spring 2| immediately engages the next sprocket tooth I5. In reverse handle movement the plunger 55 has its cam portion 5'! engage member 65 and the plunger reciprocates from the full line position-see Fig. 4--into a position approaching that shown dotted therein and without rotating the shaft |64-I 9 and, therefore,without rotating or oscillating the sprocketV locking pawl 29 to release the same from the sprocket.

It will be remembered that there has been described the engagement of the ratchet pawl carried pin 53 with the cam face 1'l of the oscillatable pawl 61 and the resulting outward movement thereof.

When sprocket pawl 20 hasrtaken the load on the next sprocket tooth, ratchet I1 stops rotating. Then, in continuing handle lifting movement clockwise as in Fig. 2, the face 1| of pawl 61, see Fig. 2, forces the pin 53 carried by pawl 49' outwardly as well asy pawl 49 and toward the dotted line position-see Fig. 3. This pawl when in the dotted line positionis then free of ratchet I1 which is held against rotation while under load by reason of the so-called inside pawl 29 holding the load sprocket. Upon reverse or counterclock- Wise handle rotation, as in Fig. 2, spring 68- is effective to hold the pawl 49 out of ratchet locking engagement until such time as the face 49a of the pawl 49 passes over the crest of the next ratchet tooth of ratchet l1. The pin 53 and face 1| when separated in the continued handle movement (anti-clockwise) as in Fig. 2 permits pawl 49 to engage in the root of the next ratchet toeth and as it follows such tooth surface, pawl 61 returns to the full line position-see Fig. 2 under the constraint of spring 68.

The two pawls 29 and 49, see Figs. l and 3, are so arranged that when there is load on the chain, both cannot be released simultaneously from the respective sprocket and ratchet.

The two` dotted line triangles-see Figs. 2 and S-indicate an angular relationship between the respective parts of the hoist heretofore described whereby the desired timing or sequence of operations described is effected.

The foregoing oscillation of the handle is repeated as often as necessary to lower the load the desired amount and by a step-by-step progression.

Whenever it is desired, plunger 56 may be held in the dotted line position, see Fig. 4, by pin 62 and the hoist handle oscillated for loadV elevation by long strokes without having the pin 56 become operative or without limiting handle stroke. When plunger 56 is not thus held retracted--see dotted lines Fig. 4-'-the handle movement is of the restricted stroke character previously described.

Free chain movement in load elevating direction is obtained by merely pulling on the chain for then both pawls ratchet over their respective ratchet and sprocket teeth. Free chain movement in the opposite or load lowering direction is obtained by having the handle positioned so that the plunger 56 holds the pawl 20 out of sprocket engagement, see dotted line position,y Fig. 1, and thumbpiece member |42 on the handle is then actuated and held depressed, which moves and holds the pawl 49 out Vof ratchet engagement when there is no load on the chain. When the pawls are thus maintained in nonengaging position relative to the ratchet and sprocket and the chain is without load, the chain can be freely moved in the reverse or load lowering direction.

Whenever the arcuate length of member 61 is suicient relative to the arcuate distance between the free end thereof and a radius through shaft I6 and pivot I9 and the arcuate distance between plunger 56 and pin 53 and there is no load on the chain, the latter may be lowered by a free chain action, that is, merely pullingfupon it, Whenever the handle lever is sopositioned, and this position is a critical one, that the ratchet pawl 49 is held out of ratchet engagement at the same time that the sprocket pawl 29 is held out of sprocket engagement, the former being effected by pin 53 being moved from the full line to the dotted line position, see Fig. 3, by proper engagement with member 61 and the latter being effected by plunger 56 simultaneously cooperating with member 65 so that the sprocket pawl 20 has been moved from the full line tothe dotted line position, see Fig. 2. The draft 49b on pawl 49 is such that, with load on the chain, the pawl 49 will not be disengaged from ratchet I1, so that with load on the chain, critical positioning of the handle is ineffective to permit free chain operation in load lowering direction; hence, dropping of the load cannot occur. The distinction to be noted is as follows:

Under load, the chain is always under an applied force so that freeing of the pawl 49y from the root of the ratchet tooth I2 cannot occur automatically at this critical position of the handle, whereas such action can occur when there is no load on the chain, for the free chain pull or force is applied to chain after the ratchet pawl is free of the ratchet tooth and while the handle is held in said critical position.

The relationship of parts 53 and 51, see Fig. 4, relative to the parts illustrated in Fig. 2 is such that if there be load on the chain, free chain operation in the load lowering' direction cannot occur and, hence, dropping of the` load cannot occur.

For safety purposes, spring 41 normally absorbs the initial movement of rod 36, see Fig. 3, tending to release the pawl 49 from ratchet engagement. As long as there is any load on the chain, pawl 49 cannot be released from its ratchet engagement due to the draft 49h of pawl 49, see Fig. 3, unless and untilv the handle is rotated sufliciently to suspend the load on pawl 29. Thus if there be load on the chain, the draft lock with spring 41 retains control and prevents free chain action in the load lowering direction even though the handle be in the aforesaid single crit-ical'p'osition. Thus dropping of the load is prevented as well.

In Figs. 5 to 8 there is illustrated a semiautomatic form of hoist embodying the invention as distinguished from the full automatic form illustrated in Figs. 1 to 4. Numerals similar to those previously employed but increased by 200 designate like or similar parts in Figs. 5, 6 and 7.

In Fig. 5 the chain 214 is omitted for clearness. In this form of the invention the handle carried pawl 249 is similarly associated with ratchet 2H and is constrained toward such engagement by spring 25|. Inside pawl 229 is similarly constrained by spring 22| toward engagement with sprocket 2I5 and is carried by shaft 2I9-264, see Figs. 5 and 6. The body exposed portion of this shaft mounts a cam faced arm 265.

The handle reciprocatorally supports plunger 256, see Figs. '7 and 8, having the cam face 251 and normally constrained toward projected position by spring 259. It may, however, be held in retracted position, in opposition to said spring by pin 263 as previously described relative to pin 63, see Fig. 4.

The handle 235 carries a lever 239 having thumbpiece or enlargement 342 for reciprocating rod 236 which through stiff spring 241 tilts 4pawl 249 out of ratchet engagement.

The remainder of the parts shown in Figs. 5 to 8, inclusive, are similar to correspondingly primary numbered parts illustrated in Figs. 1 to 4, inclusive, and operate in substantially the same manner.

When the handle 235 herein is rotated clockwise in Fig. 5 the load is elevated. Herein the pawl 220 holds the load when the handle is reversely rotated to make another connection with ratchet 2H by means of pawl 249, the latter ratcheting over the teeth 2H in this movement. The original handle movement and reversal thereof is repeated as often as necessary to elevate the load in the manner described relative to Figs. 1 to 4.

For load lowering the arm 265 and plunger 256 similarly cooperate. When the rotation is in one direction plunger 256 is not retracted and arm 265 and shaft 219 is rocked for release of pawl 220. When the rotation is opposite thereto only plunger 256 is forced to move inwardly or to the right, see Fig. 8. Pawl 249 is retracted from ratchet engagement by depressing enlarged portion 342 at the free end of the handle.

From the preceding description of operation of full automatic form of the invention, it is obvious that the load is lowered step-bystep by alternately disassociating the two pawls, the handle pawl being manually retracted from ratchet engagement and the sprocket pawl being automatically retracted from sprocket engagement, hence the designation semi-automatic operation. No further specific description is believed necessary relative to Figs. 5 to 8 in View of the full and complete description of the full automatic form of the invention for a complete understanding of the parts embodied in this form of the invention, see Figs. 5 to 8, or its operation.

Whenever the term ratchets is used as a verb or plural noun, it is used in the sense that the sprocket pawl pivots relative to the sprocket teeth in sprocket movement, or the ratchet pawl pivots relative to the ratchet Vteeth in handle-shaft relative movement for the verb, and as a noun, it comprehends both ratchet and sprocket. Also, the term to and fro movable or to and fro movement has been used in the claims in a generic sense and is intended to include move'- ment, or a member which has movement either specically reciprocatory or oscillatory.

VWhile the invention has been illustrated and described in great detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character.

The several modications described herein as well as others which will readily suggest themselves to persons skilled in this art, all are considered to be within the broad scope of the invention, reference being had to the appended claims. V

The invention claimed is:

1. In a handle operable chain hoist, the combination with a support structure, a load chain sprocket, a ratchet, a shaft rigid with both and supported by the structure, an oscillatory handle for shaft movement and load control, a sprocket engaging pawl supported by the structure and normally constrained to sprocket engagement for load holding purposes, a handle carried pawl `normally constrained to ratchet engagement for shaft rotation and load holding purposes, and handle carried manually operable means for removing the ratchet pawl from ratchet engagement in opposition to the ratchet pawl constraint,

of means directly connected to the sprocket pawl and movable therewith, means carried by the handle and reactive with said directly connected means in a certain portion of handle movement in load lowering operation for effecting release of the sprocket pawl for load lowering, the handle carried pawl carrying the load during such handle movement, and a fourth means effective in the continuation of the handle in lowering direction for release of the ratchet pawl from ratchet engagement, such release occurring sufficiently after sprocket pawl release to permit sprocket lowering rotation and subsequent sprocket pawl-sprocket engagement, handle movement in the opposite direction repositioning same for further load lowering, the cooperation between the directly connected andV third mentioned means in said opposite direction being ineffective for sprocket pawl release, and the fourth mentioned means upon initial movement of the handle in said opposite direction being effective to hold said ratchet pawl out of ratchet engagement for at least one ratchet tooth equivalent-of handle movement.

2. In a handle operable chain hoist, the combination with a support structure, a load chain sprocket, a ratchet, a shaft rigid with both and supported by the structure, an oscillatory handle for shaft movement and load control, a sprocket engaging pawl supported by the structure and normally constrained to sprocket engagement for load holding engagement, a handle carried pawl normally constrained to ratchet engagement for shaft rotation and load holding purposes, of means directly connected to the sprocket pawl and movable therewith, means carried by the handle and reactive with said directly connected means in a certain portion of handle movement in load lowering operation for effecting release of the sprocket pawl for load lowering, the handle carried pawl carrying the load during such handle movement, and a third means effective in the continuation of the handle in the lowering direction for release of the ratchet pawl from ratchet engagement, such release occurring sufficiently after sprocket pawl release to permit sprocket lowering rotation and subsequent sprocket pawlsprocket engagement, handle movement in the opposite direction repositioning same for further load lowering, the cooperation between the directly connected and second mentioned means in said opposite direction being ineffective for sprocket pawl release, and the third mentioned means upon initial movement of the handle in said opposite direction being effective to hold said ratchet pawl out of ratchet engagement for at least one ratchet tooth equivalent of handle movement.

3. In a handle operable chain hoist, the combination with a support structure, a load chain sprocket, a ratchet, a shaft rigid with both and supported by the structure, an oscillatory handle for shaft movement and load control, a sprocket engagingV pawl supported by the structure and normally constrained to sprocket engagement for load holding purposes and a handle carried pawl normally constrained to ratchet engagement for shaft rotation and load holding purposes, the handle having to and fro movement relative to the support for load elevation and to and fro movement for load lowering, of means operatively associated with the handle and the support structure for transferring the load alternately to said pawls for effecting step by step lowering movement of the load in one range of to and fro movement of the handle, the other range of to and fro movement of the handle automatically elevating the load, the two ranges of to and fro handle movement having contiguous relation with adjacent portions of said to and Vfro handle movements overlapping, said means including a to and fro movable member carried by the handle and having a 'cam face, and -a yieldingly mounted abutment member upon the structure, bodily movement -of -one of the Ylast two mentioned members relative to the other of said members in one direction of handle movement for load lowering eiecting to vand fro :movement of the said other member, relative movement of the first mentioned member in the opposite direction -of handle movement being ineffective -for movement of the said other member -by reason lof said cam face.

f4. In a handle operable chain hoist, the combination with a support structure, a load chain sprocket, a ratchet, a shaft rigid with both and supported by the structure, an oscillatory handle for shaft movement and load control, a sprocket engaging pawl supported by the .structure and normally constrained .to sprocket engagement for load holding purposes and a handlecarried pawl normally constrained to ratchet engagement for shaft rotation and `load holding purposes, the handle having to-and fro movement .relative to the support `for load .elevation and yto and fro movement for load lowering, of means operatively associated with the handle andthe .support structure -for transferring the .load .alternately to said pawls for effecting step by `step lowering .movement-of the load invone range .ofto and fro movement -of the handlathe .otherrange of `to and fro movementof the handle .automatically elevating the load, the two ranges of to .and fro .handle movement having-contiguous relation with adjacent portions-of said to and .fro .handle movements overlapping, said means including a to and fro movable member carried by .the handle .and having -a -cam face, and a yieldingly mounted abutment member upon -the structure, bodily movement -of one -of the last two `mentioned-members relative tothe other of said members in one direction of handle movement for load lowering eecting to `'and fro movement -of the -said .other member, relative movement-of `the rst mentioned member in the opposite directionof handle movement being ineffective for movement vof the said other member fby reason of said cam face, and means yieldingly constraining -each -of `said last two mentioned members to predetermined position.

`5. In .a handle-operable -chain hoist, the combination vwith a support structure, a -load chain sprocket, a ratchet, a shaft rigid with both and supported bythe structure, an oscillatory Ahandle for vshaft movement and load control, -a sprocket engaging pawl `supported by the structure and normally constrained-to sprocket engagement for load holding purposes and-a handle lcarried pawl normally constrained to ratchet engagement for shaft `rotation and load holding Purposes, the handle having to `and fro movement Yrelative to the support for load elevation and to and fro vmovement -for load lowering, of `means operatively associated 4with the -handle v.and the support structure for transferring the load alternately to said p'awls for effecting step by step lowering movement of the load in one range of to and rfro movement `of the handle, the other range of to and fro movement ,of the handle automatically elevating the load, `,the two ranges of to and fro handle movement having contiguous relation with adjacent portions of said to and f-ro handle movements overlapping, said means including a pair of alternately `operable mechanisms, one of the mechanisms having `operative association with the ratchet pawl and the other of the mechanisms having operative association with the sprocket pawl, each alternately operable mechanism including .a to and vfro movable member, and a yieldingly mounted cooperating abutment member, one `of said members of each mechanism having a `cam face, Abodily movement of one member of each mechanism relative to the other member of that mechanism -in one .direction of handle movement for load lowering purvposes effecting a to and tro movement .of the said other member of that mechanism, relative movement of the rst mentioned member of that mechanism in the opposite direction of handle movement being ineffective for movement .of .the other member of -that mechanism vby reason .of said cam face.

6. In a handle operable chain hoist, the `combinationfwith a support structure, a load `chain sprocket, a ratchet, a shaft rigid with both .and supported -by the structure, an oscillatory handle for .shaft movement .and load control, a sprocket engaging pawl supported `by the structure ,and normally constrained to sprocket engagement for load -holding purposes and ea handle .carried .pawl normally constrained to `ratchet engagement for shaft rotation .and load holding purposes, the handle having to and fro .movement relative to the support for load velevation ,and to and Vfro movement for load lowering, of .means operatively associated with .thehandle and the supportstructure for .transferring the load alternately to said pawls for effecting step by step lowering movenment of theload in one range of to and fro movement of the handle, the otherrangt yof .to and fro movement ofthe handle automatically elevating the load, the two ranges of to and fro handle movement having contiguous relation with adjacent portions .of said to and fro handle move- -ments overlapping, said means including a Apair Aof alternately operable mechanisms, one of the mechanisms having operative association with lthe ratchet pawl .and the other of the mechanisms having operative association with the sprocket pawl, .each alternately .operable mechanism including a to and fro movable member, and a yieldingly mountedcooperating abutment member, one of said members of each mechanism having a cam face, bodily movement of ,one member of each mechanism .relative to the` other member of that mechanism in `one direction of handle movement for load lowering purposes leffecting a to and fro movement of the said other member of that mechanism, relativemovement of the rst mentioned member of that mechanism in the opposite direction of handle movement being ineffective for movement of the other member of that mechanism by reason of said cam face, and means yieldingly constraining each member to a predetermined position.

7. A hoist as defined by claim 1, characterized by the addition of manually operable means for moving the sprocket pawl cooperating handle carried means into inoperative position for preventing cooperative action Vin handle movement of said last mentioned handle carried means.

'8. A hoist as dened by claim 2, characterized by the addition of manually operable means for moving the sprocket pawl cooperating handle carried means for preventing cooperative action in handle movement of said last mentioned handle carried m-eans and said sprocket pawl directly connected means.

9. In a hoist, the combination with a pair of pawls, a sprocket engaged by one pawl, a ratchet engaged by the other pawl, a shaft rigid with the sprocket and ratchet, an operating handle having to and fro movement and carried by the shaft, and a support structure for said shaft and sprocket pawl, and the ratchet pawl being carried by the handle, of a pair of spaced and to and fro movable members supported by said structure, one of said members having a relieved portion at one side thereof and a laterally directed portion projecting oppositely therefrom and having a cam face, the other to and fro movable member having a cam face, each member being spring constrained to predetermined position, a second pair of members having a predetermined spacing therebetween and carried by the handle v simultaneously movable to and fro therewith, one of the handle carried members passing between the support carried members, the other handle carried member passing eXteriorly of the outermost support carried members, simultaneous movement of the handle carried members in one direction of handle movement causing operative engagement between the said handle carried eX- teriorly passing member and the outermost member for moving the latter in one direction, simultaneous movement of the handle carried pair of members in the opposite direction of handle movement being ineffective for said last mentioned movement, the intermediate passing or other handle carried member in said last mentioned simultaneous movement being eiective for moving the innermost to and fro movable support carried member.

10. A hoist as dened by claim 9, characterized by the addition of means normally constraining said second pair of members to a predetermined position.

11. In a handle operable chain hoist, the combination with a support structure, a load chain sprocket, a ratchet, a shaft rigid with both and supported by the structure, an oscillatory handle for shaft movement and load control, a sprocket engaging pawl supported by the structure and normally constrained to sprocket engagement for load holding purposes, a handle carried pawl normally constrained to ratchet engagement for shaft rotation and load holding purposes, and handle carried manually operable means for removing the ratchet pawl from ratchet' engagement in opposition to the ratchet pawl constraintof means directly connected to the sprocket pawl and movable therewith, and other means carried by the handle and movable therewith, said last mentioned other means in handle movement for load lowering operatively engaging the directly connected means for sprocket pawl movement in opposition to its constraint to free the sprocket from that pawl for sprocket rotation in load lowering direction under load, said handle carried ratchet pawl and handle carrying the load, while said handle continues its load lowering movement, said last mentioned other means in handle movement in the opposite direction being ineffective for actuating the directly connected means to release the sprocket pawl from sprocket engagement, the handle carried manually operable means when actuated after directly connected means operation releasing vthe ratchet pawl from ratchet engagement, the sprocket pawl then carrying the load and permitting free handle movement in said opposite direction.

l2. A hoist as defined by claim 11, characterized by the said other means being manually operable other than by handle movement and normally spring constrained to operative position for sprocket pawl directly connected means contact in each direction of handle movement for load lowering, said other means when manually operated in opposition to its constraint having no contact with said directly connected means regardless of handle movement.

13. A hoist as deiined by claim 11, characterized by the said other means beingrmanually operable other than by handle movement and normally spring constrained to operative position for sprocket pawl directly connected means contact in each direction of handle movement for load lowering, said other means when manually operated in opposition to its constraint having no contact with said directly connected means regardless of handle movement, and manually releasable means for retaining the said other means in retracted position in opposition to its constraint for free chain operation when the hoist is devoid of load. Y V

14. In a handle operable chain hoist, the combination with a support structure, a load chain sprocket, a ratchet,Y a shaft rigid with both and supported by the structure, an oscillatory handle for shaft movement and load control, a, sprocket engaging pawl supported by thestructure and normally constrained to sprocket engagement; for load holding purposes, a handle carried pawl normally constrained to ratchet engagement for shaft rotation and load holding purposes, and handle carried manually operable means for removing the ratchet pawl from ratchet engagement in opposition to the ratchet pawl constraint, of means directly connected to the sprocket pawl and movable therewith, and other means carried by the handle and movable therewith, said last mentioned other means in handle movement for load lowering operatively engaging the directly .connected means for sprocket pawl movement in opposition to its constraint to free the sprocket from that pawl for sprocket rotation in load lowering direction under load, said handle carried ratchet pawl and handle carrying the load while said handle continues its load lowering movement, said last mentioned other means in handle movement in the opposite direction being ineffective for actuating the directly connected means to release the sprocket pawl from sprocket engagement, the handle carried manually operable means when actuated after directly connected means operati-on releasing the ratchet pawl from ratchet engagement, the sprocket pawl then carrying the load and permitting free handle vmovement in said opposite direction, said other means and said directly connected means each having a cam face portion, each face portion of one means cooperating with the other for the purpose described.

15. A hoist as dened by claim 14, characterized by the said other means being manually operable other than by handle movement and normally spring constrained to operative position for sprocket pawl directly connected means contact in .each direction of handle movement for load lowering, said other means when manually operated in opposition to its constraint having no contact with said directly connected means regardless of handle movement.

16. A hoist as deiined by claim 14, characterized by the said other means being manually opcontact with said directly connected means reerable other than by handle movement and norgardless of handle movement, and manually remally spring constrained to operative position leasable means for retaining the said. other for sprocket pawl directly connected means conmeans in retracted position in opposition to its tact in each direction of handle movement for 5 constraint for free chain operation when the load lowering, said other means when manually f hoist is devoid of load. operated in opposition to its constraint having no FREDRICK W. COFFING.

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