US2561138A - Winch, hoist, and the like - Google Patents

Description

July 17, 1951 M. F. SASGEN 2,561,138

WINCH, HOIST AND THE LIKE Filed May 1, 194'? INVENTOR. MA TTHIAS F. SAS GEN Patented July 17, 1951 WINCH, HOIST, AND THE LIKE Matthias F. Sasgen, Chicago, 111., assignor to Sasgen Derrick 00., Chicago, 111., a corporation of Illinois Application May 1, 1947, Serial N 0. 745,165

1 Claim.

v v This invention relates to winches, hoists and like apparatus, and particularly the invention relates to such apparatus wherein the lowering of the-load iscontrolled by an automatic braking action that requires positive actuation of the apparatus in a lowering direction.

In the patent to Jesse M. Benson, No. 2,254,989,

patented September 2, 1941, there is disclosed a winch or hoisting apparat'us'that embodies an advantageous safety arrangement that tends to minimize the risk normally involved in hoisting of heavy loads or in raising and lowering scaffolds and the like, and an important object of the present invention is to increase the safety of operation of winches, hoists and apparatus such as that illustrated in the aforesaid Benson patent. v

The safety feature that is thus disclosed in the aforesaid Benson patent comprises an automatic brake that is effective in a load-lowering operation to apply braking forces to the drum in such a manner as to require actuation of the operating means such as a crank handle in a lowering direction in order to cause lowering of the load. In the use of hoists or fwinches of the aforesaidcharacter in the field it has been found that workmen place great reliance in the automatic braking action that is attained as aforesaid in the winches or hoists made under and in accordance with the Benson patent, and such "of the invention.

Other and further objects of the present invention will be apparent from the following description and claim and are illustrated in the accompanying drawings which, by way of illustration show a preferred embodiment vand the principle thereof and what I now considerto be the best mode in which I have contemplated applying that principle. of the invention embodying the same oreq-uiv- Other embodiments alent principle I may be used and structural changes may be'made as desired by those skilled Tintheart without departing from the present invention and the purview of the appended claim.

In the drawings, Fig. 1 is an end elevational view of a winch embodying the features of the invention and showing the crank handle in safety position;

Fig. 2 is a side elevational view taken partially in transverse section and showing the winch with the crank handle in its normal or operating position;- Figs. 3 and 4 are fragmenta'l sectional views drum shaft 2 showing the parts of the operating mechanism in different positions; 1

Figs. 5 and 6 are sectional views taken respectively along the line 55 of Fig. 3 and the line 66 of Fig. 4; and

Fig. 7 is an enlarged sectional view similar to Fig. 2, by showin the parts inv the position of Fig. 4.

In the form chosen for disclosure herein the invention is embodied in a relatively small or light winch IE3 having the operating means mounted permanently on the winch frame and adapted, for example, for use in raising and lowering a scaffold or the like, and as will hereinafter be described in detail the winch ID has three safety features that cooperate in attaining safe operation even in the hands of an unskilled operator. Thus, as will be evident in Figs. 1 and 2, the winch III has a pair of elongated and vertically disposed side frames II and I2 connected together in spaced relation to afford space therebetween within which a winding drum I3 is rotatably supported on a transverse I I that extends between and is mounted in suitable bearing bosses I5 formed on the respective side frames II and I2. At their lower ends the side frames I I and I2 are"con nected in the desired spaced relation by a spacer bar" I6 and connecting bolts I'I, while at their upper ends, a spacer sleeve I8 and a connecting bolt l9 serve to hold the frames II and I2 in the desiredrelation.

The drum It as herein shown comprises a .cylindrical barrel 20 havinga plain flange 2| and a driving or gear flange 22 secured to 'opposite ends thereof as by welding at 23, and the flanges 2| and 22have central hubs 24 that embrace the shaft 14 and afford the desired rotatable bearing'sifor. the drum I3. The gear flange "22 in the present instance has external gear teeth 2 5 formed about the periphery thereof, and vthe gear flange 22 is disposed so as to be adjacent to the side frame I2, which is termed the crank frame of the winch, and this crank frame .-'I 2 is'larranged tosupport, and in part to house, the actuating and control mechanism whereby the drummovements are controlled. Thus the "side frame I2 is so formed at its upper end as to afford a chamber 2! that isdisposed outwardly, or to the right in Fig. 2, from the outermost face of the gear flange 22, and-this chamor the left in Fig. 2. The open inner or left hand face of the chamber 21, Fig. 2, is closed by a closure plate 28 that is held in position by pins 29, so that the chamber 21 affords a housing for the major elements of a safety braking mechanism as will hereinafter be described in detail.

. In affording the safety'braking mechanism as 2,5e1,1ss

well as an actuating means for winding or unwinding a cable C on the drum it, such means are mounted permanently on the frame of the winch, rather than as a separate unit or attachinent as shown in the aforesaid Benson patent, but it will be recognized that the features of the present invention may be utilized in such a separate unit or attachment. Thus, an actuating shaft 30 is extended through the two side frames I I and [2 so as to pass through the chamber 21 somewhat above the upper edge of the gear flange 22, and the left hand end of the shaft 30 is rotatably supported in a hub 3| formed on the side frame ll, while an enlarged cylindrical head 39H on the other end of the shaft 30 is rotatably supported within an outwardly projecting hub 32 formed on the wall IZA of the chamber 21. At its outer or left hand end the cylindrical. head 30H has a radially related tongue 311T that projects to the right and is embraced by the bifurcated end of a handle-supporting casting 33, the casting 33 being pivoted to the tongue 30'1 by a pivot bolt 34 so as to permit reversal of the handle from the operating position of Fig. 2 to the safety position of Fig. l. The handle casting 33 has a radial arm portion 33A in which a radial arm 35 is secured by rivets 36, and at the end of the arm 35 a laterally projecting crank handle 31 is mounted.

. Thus when the handle 31 is in the operating position shown in Fig. 3, the operator may grasp the handle 31 and impart rotative movements to the shaft 38,, and such movements are effective to, cause operation of the winding drum l3 as well as the safety braking mechanism.

In attaining such operation, the shaft 30 has a pinion 40 mounted thereon so as to mesh with the gear teeth 25 of the gear flange 22, and

.the portion of the shaft 30 that is embraced. by

the pinion 4!] has external screw threads 4| formed thereon so asto engage internal threads 42 formed in the central bore of the pinion 40. To the left of the pinion 40, a stop collar 43 is secured on the shaft 30 by a pin 44, while to the right of the pinion 40, and within the.

chamber 21, a safety ratchet 45 is rotatably mounted on the shaft 30. A safety pawl. 46, pivoted on the bolt l9 within the chamber 21, extends to the right in Fig. 1, and is arranged to engage teeth 45T of the ratchet 45 to prevent rotation of the ratchet 45 in a counter-clockwise or unwinding direction, Fig. 1. The ratchet 45 has a central web 45W that engages a smooth or cylindrical surface of the shaft 30, and the wider flange portion of the ratchet 45 outwardly.

of the web 45W is arranged to alford opposite faces formed flat and parallel so as to be disposed'in planes perpendicular to the axis of the 'shaft 30, and these annular flat faces are utillzed as friction clutch surfaces. Thus, a friction disc 41 is rotatably mounted on the shaft and facing to the right so that the friction disc 48 may be clamped between the shoulder 40S and the adjacent annular face of the ratchet 45.

When the winch H) is being used for supporting a. load, the cable C will of course apply the load to the drum 13 in what may be termed an.

unwinding direction so as to resist winding movement of the drum, and hence this load or force acts to hold the pinion 40 against rotation in a winding direction, and the lead of the threads 4| and 42 is such that when the crank handle '3'! is operated in a clockwise or winding direction, Fig. l, the effect will be to draw the pinion 40 to the right, Fig. 2. With this arrangement, the load will tend to produce a similar right hand movement of the pinion 40 when the shaft 30 is held against rotation. This will clamp the friction disc 41 between the ratchet 45, thereby to drivingly connect the shaft 30 t0 the ratchet 45, and at the same time the friction disc 48 is clamped between the shoulder 40S and the other face of the ratchet 451:0 thereby drivingly connect ratchet 45 to the pinion 40. Thus, the: operation of the handle '31 in a winding direction serves through the threads 41 and 42 to engage frictionv clutch elements that connect the shaft 30, the ratchet 4.5 and the pinion 40 as a unit which transmits: the winding motion of the drum i=3. As such, winding "progresses, the pawl 46 rides over the teeth 45T of the ratchet, thereby to prevent retrograde motion, of the ratchet, and this of course serves as av safety to prevent undesired unwinding of the drum- In addition, a safety pawl 50- is pivoted on the bolt l9 just to the left of the plate 28, Fig. 2, so as to project to the left, Fig. 1,. and this pawl 50 rides over the teeth- 25 of the gear flange 22 so as to hold the drum [3 against unwinding movement. It should be noted. that while the safety pawl 50 is desirable, and affords an additional safety feature, it is common practice in winches of this character to rely entirely upon the ratchet 45 to hold the. drum against unwinding movement, and to utilize the pawl 50 or its equivalent only in a brake. or clutch. releasing operation as will hereinafter be described.

In the use of. the winch ID, as for example in the raising or lowering of. a scafiold, the scafiold is connected to the lower spacer. bolts [1 by means including hanger bars 52.. The cable C has one end connected to the drum l3 and then extended upwardly past and to the right, Fig. l, of a cable guide spool 53- that is journaled on a bolt 54 that is extended between arms 55 that are extended to the left, Fig. 1, from the upper ends of the respective frames [I and I2. Additional arms 56 are secured to the arms 55 by the bolt 54 so as to project additionally to the left, and a hand grip including a bolt 51- and a sleeve 51S is extended between the arms 56 so as to be disposed above an operating ring 58 formed adjacent to the end of the safety pawl 58. Thus the operator may grasp or rest one hand on the hand grip 51 while using one finger or the thumb of this hand to raise or releasethe pawl 50 when this is required to enable the load to be lowered.

With respect to the attainment of such lowering of the load, it should be observed that. the pawl 55 is housed within the chamber 21 so as to be engaged with the ratchet 45 at all times, and hence the ratchet 45 is held against retrograde movement. Thus, in order to enable the desired lowering movement of the load to be attained, the pinion 45 must be released from the ratchet 45 in such a way as to permit controlled retrograde or lowering rotation of the pinion 4!] with respect to the then stationary ratchet 45. It will be recognized that in the course of the preceding raising or lifting operation the operation of the crank handle 31 in a winding direction. has been resisted by the load through the pinion 4|]- so as to thereby tightlyclamp the friction discs 41 and 48 between the shoulders S and 48S and the opposed annular faces of the ratchet,

and hence as a preliminary to a load lowering dle 31 and serves to release the previously established clamping forces between the various fricrtio-n clutch elements, thereby to free the pinion '40 from the restraininginfluence of the then stationary,ratchet 45; .When suchrelease of the pinion 49 has thus been accomplished the safety pawl 5Il-is still effective, thereby to hold the drum =13 against unwinding movement, and to initiate the desired lowering movement, the pawl 50 must be released. When'this is'to be done, the operator normally holds the crank handle 31 with one hand, while grasping the hand grip 5'! and the pawl 50 with the other hand in the manner hereinbefore described. When the load is relatively ,small, the pawl 50 may be-withdrawn without utilizing the crank handle to release the load or force on thepawl 5.8., In such an instance, when the pawl filllis released; the shaft is held by the crank -h'andle 31 against rotation, while the load normally becomes effective to rotate the pinion 40 slightly on the shaft 30 in a clamping direction so as to thereby cause the pinion 46 to move in a right hand direction, Fig. 2. This effects a clamping of the friction disc 48 between the shoulder 40S and the then stationary ratchet 45, and such clamping forces cause a braking action which stops the pinion 40 after but a slight rotation in a lowering or unwinding direction. In the event that the load is relatively great, it is usually necessary to rotate the handle in a winding direction in order to relieve the force on the safety pawl 50, and when this is done, the parts move to the clamped relation shown in Figs. 3 and 6. This relation thus conditions the apparatus for braking operation as the load is lowered.

In such lowering operation the handle is rotated in a lowering or unwinding direction, thereby to progressively tend to release the clutches that act on the ratchet 45, and as this releasing action takes place, the load acts on the pinion 40 so as to cause the same to follow the unwinding rotative movements of the handle. Hence the friction disc 48 is effective to control the lowering or unwinding movement of the pinion 40, and but little force is required in operating the handle. Moreover, this force must be positive in an unwinding direction, and the control or restraining forces exerted on the pinion are afforded by the friction clutch means in accordance with the load.

In prior winches and hoists made under and in accordance with the aforesaid Benson patent, the operation of the safety brake that is described in such Benson patent has in most instances been such as to afford complete safety of operation of the apparatus, but it has been found that in the hands of a careless or unskilled operator the safety brake may in effect be inadvertently disabled in the course of the release operation .-This constitutes a releasing operation of the han- 6 that has been above described; In other words, the releasing of the various clutch elements by movement of the pinion or a connected part axially of the shaft may in the prior structures be carried to such an extent as to cause the pinion or the related element to be locked to the operating shaft so firmly that the load applied to the pinion from the drum of the Winch will be unable to rotate the pinion relative to the shaft and back to its clamping position, and hence the full force of the load will be transmitted to the handle so as to break. the operators grip. Under the present invention means are afforded whereby such undesired locking of the pinion to the operating shaft is positively eliminated. Thus as will be evident in Figs. 2 to 7, means are afforded for so limiting the rotating movement of the pinion 4G with respect to the operating shaft 3Q that endwise wedging movement of the pinion against the related or opposed end surface of the collar 43 is prevented, and the limiting means are of such a character that the limiting abutment of opposed elements is in the nature of a flat surface contact wherein the elements move toward and away from each other in a direction that is substantially perpendicular to the plane of their abutting contact. Thus the collar 43 has an arcuate slot 60 formed therein so as to afford abutment surfaces 60A and. 603 at its opposite ends. The arcuate slot 60 is formed in theface of the collar 43 that is adjacent to the pinion 4i), and the pinion 49 has a lug 62 formed on the adjacent end thereof so as to project into .the slot Eli. The slot 6i! isso located-in a rotative sense with respect to the shaft 3B that when the operating shaft 30 is rotated in an unwinding direction in the course of a releasing operation as above described, the end shoulder or surface 60 A of the slot 60 will engage the adjacent side edge of the tooth 62 when such unwinding or releasing movement of the shaft has been carried to an extent sufficient to release the friction plates 41 and 48, and such engagement of the shoulder 60A with the tooth 62 takes place prior to the r time when the adjacent end surface NE of the pinion has engaged the end surface of the collar 43. It will also be observed that the length of the tooth 62 with respect to the depth of the slot 60 is such that when the elements are in the released position of Figs. 3 and 5, the end of the tooth will be spaced from the bottom of the slot 58. Thus it will be clear that the releasing movement of the pinion 40 with respect to the operating shaft 36 is limited solely by the engagement of the side edge of the tooth 62 with the end surface 50A of the slot, and because of this the pinion 40 does not have an opportunity to move into a wedging, end-to-end engagement with the collar 43. Thus the possibility of a locking en:- gagement of the and surfaces of the pinion 40 and the collar 43 is avoided, and the pinion 40 may be freely returned to its active or braking position at any time when the load is allowed to become effective to rotate the pinion in a clamping or clutchin direction.

When the operatin shaft 3!! is turned in a winding direction, the shoulder 66A of the slot 60 is moved away from the tooth 552 and the parts assume substantially the relationship shown in Figs. 4 and 6 of the drawings, and in this relationship it will be noted that the tooth 62 is spaced from the end wall or abutment 60B of the slot Gi This relationship is of course important in that the clamping action of the pinion 49) must be free so as to be limited only by attainment of such clamping or clutching action; The slot 50 is preferably arranged so that the end 663 thereof will be so located that wear upon the friction elements 4? and 43 may take place in a reasonable amount without causing the tooth 62 to engage the abutment 563 when the parts are in the winding position of Fig. 4.

In the use of the winch of the present invention, the reversible handle may be located in the safety position of Fig. 1 so as to engage the frame of the winch to prevent unwinding movement thereof. In addition, the safety pawl 50 may be located in its safety position of Fig. 1 and this affords a second safety feature. The friction brake arrangement that is afforded by the screw threaded connection of the pinion 40 with the shaft so affords a third safety feature, and through the provision of a non-binding limiting stop for limiting the releasing movement of the Thus, while I have illustrated and described the preferred embodiment of my invention, it is to be understood that this is capable of variation and modification and I therefore do not wish to be limited to the precise details set forth, but desire to avail myself of such changes and alterations as fall within the purview of the followin claim I claim:

' In a hand operated winch or the like, a frame,

a shaft rotatably mounted in said frame for rotation selectively in lifting and lowering directions, a ratchet loosely mounted on said shaft concentrically therewith, a pawl pivoted on said frame and normally engaged with said ratchet to hold the same against rotation in said lowering direction, a pinion mounted for rotation on said shaft adjacent to said ratchet, cooperating screw thread means on said shaft and said pinion having a lead direction arranged to shift said pinion axially in a brake applying direction along said shaft toward said ratchet when said pinion is retated in a lowering direction relative to said shaft, a' first friction disc non-rotatably fixed to said pinion in position to engage one side face of said ratchet when said pinion is shifted axially in said brake-applying direction, a second friction disc rotatably mounted on said shaft on the other side of said ratchet and in position to engage the other face of said ratchet, a shoulder on said shaft against which said second friction disc may bear to limit movement of said second friction disc by said first disc when said first disc is moved in said brake-applying direction, and stop means rigid on said pinion and said shaft respectively and engageable in a plane substantially parallel to the axis of said shaft to limit rotation of said pinion relative to said shaft.

' MATTHIAS- F. SASGEN.

REFERENCES CITED UNITED STATES PATENTS Name Date Benson July 29., 1947 Number

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