US1937331A - Automatic reverse ratcheting hoist - Google Patents

Description

-Filed Feb. 25`,A 1952 3 Sheets-Shes??l ...l

A" le INVENTOR.

Nov? 28, 1933. F. w COFFINQ V- 159157,331

AUTOMATIC REVERSE RATCETING oIsT Filed Feb. 25, 1932 3 Sheets-Sheet 2 INYENTOR. Y FFfa/C WCofw/v.

ATTORNEYS.

NOV 28, 41933- F. w. COFFING 1,937,331-

AUTOMATIC VESE RATCHETING HOIST INVENTOR. maak/cx n. Cof-FWG.

ATTORNEY- Patented -Nov. 2,8, 1933 UNITED STATES I'PATENT OFFICE l Claims.

This invention relates to a free chain hoist and is an improvement upon and a continuation in part of the invention disclosed in the co-pending application, Serial No. 389,956, led September 3,

5 1929, and entitled Automatic reverse ,ratcheting hoist, which is now Patent No. 1,862,331, dated June 7, 1932.

This invention is an improved and'simplied structure wherein a free chain puller hoist is substantially fool-proof, and the invention consists in the provision of a reversible sprocket associated with a load supporting chain and an actuating and locking means for said sprocket which permits the chain to advance or retire step by step or permits the free movement of the chain for a quick and approximate positioning When there is but little or no weight on the chain.

One object of the invention is to simplify the actuating and locking means so that the same 2o results may be obtained by a structure comprised of fewer parts and in a more ecient manner and in a fool-proof manner, particular reference being had to the safety of the operator of the device. l The last mentioned object is accomplished by one feature of the invention, to wit, the prevention of the complete rotation of the actuating handle or lever and the locking of the handle upon either side of the hoist to prevent its accidental movement from one side of the hoist to the other, but to permit intentional movement from one side of the hoist to the other for selective side opera-v tion.

Another feature of the invention consists in the mechanism provided for permitting the interchangeable positioning of the lever from one side to the other, also being arranged to move certain parts into predetermined position to permit free running of the chain for predetermined rapid positioning of the chainand in this respect this last mentioned mechanism accom- 'plishes the same result as the mechanism specically provided for that purpose.

Thefull nature of the invention will be understood from the accompanying drawings and the following description and claims:-

In the drawings, Fig. 1 isa central sectional view of the handle, several of the parts being shown in elevation.

Fig. 2 is a 'side elevation of a. portion of the hoist mechanism, the handle being removed, exposing theY ratchet and the control ring, parts being shown in the so-called lowering position.

Fig. 3 isa view similarto Fig. 2 but illustrates the parts in an elevating position.

Fig. 4 is a perspective view of the handle, a part being broken away to show the parts in section and particularly the handle control mechanism in perspective.

Fig. 5 is an elevational view of a part of the 60 handle showing the control mechanism in the load releasing position or free chain lowering position.

Fig. 6 is a view similar to Fig. 5 but illustrates the parts of the control mechanism in position, permitting diametrical reversal of the handle with respect to the housing.

Fig. 7 is a sectional view taken on section 7-7 of Fig. 1 and in the direction of the arrows and illustrates the portion of certain parts similar to position of the same parts shown in Fig. 2.

Fig. 8 is a sectional view taken on the same section line and in the direction of the arrows and illustrates the position of certain parts silnilar to the position of the same parts shown'in 75 Fig. 3.

Fig. 911s a side elevation of the hoist body, chain and a. portion of the handle showing the latter stopped in its movement by a portion of hoist body.

Fig. 10 is a diagrammatic view of relative positions of the handle and cooperating elements therein associated with the body parts, the handle in full lines indicating one limit position (right hand) and the handle in dotted lines and indicating another limit position (left hand) when handle is positioned upon left or right side of the hoist respectively and conditioned for chain travel in the same direction by the handle.

In the drawings 10 indicates the body portion 90 of a hoist which is formed of two substantially similar but complementary, preferably malleable iron, half portions, secured together as by ,riveting or the like. The housing or body portion thus formed, includes two inclined channels 11 and 95 12 which simultaneously communicate with each other and chamber 13.r Pivotally mounted in the bearings 14 and 15 in the housing is a spindle 16 which extends through the body housing and mounts in chamber 13 an integral sprocket 17, 100 the teeth of which project into the channels at the meeting location and mesh with the links 18 of the load supporting chain positioned in said channels.

One end of the chain may support a suitable hook or load sustaining member. The housing 10 swivably supports at 21 a similar anchoring hook 20. The channel 12 and swivel axis ol hook 20 rare in line and the line is tangential to the sprocket and chain contact so that the load is taken by the sprocket as a tangential load and is in line with the two hooks mentioned.

In chamber 13 there is pivotally mounted a locking pawl 23. Shaft 22 which supports said pawl extends through the body wall 10 and projects into the lever handle housing '7. The pawl 23 is maintained in the locking position to prevent dropping of the weight and the chain, and by a multiple spring, including a coiled spring 24 having one end connected to the pawl and its other end connected to aat spring 25 which in turn has its other end secured to the frame as by the rivet 125.

The load is elevated by counterclockwise rotation, reference being had to Figs. 2,.,and 3, of sprocket 17 through the lever handle 29, hereinafter to be described, which raises the chain 18 and elevates the load. In this movement, the pawl 23 yautomatically ratchets over and seats itself behind each successively presented sprocket tooth to preventfreverse movement of the sprocket while the actuating portion including the lever handle, is' being reversed for further subsequent rotation.

`The mounting of the lever handle 29 is'shown particularly in Fig. l and the lever handle itself is Vshown particularly in Figs. 4 to 6, inclusive. The spindle 16 in addition to being provided with a sprocket gear including an integral, ground, cylindrical portion 27 having ratchet teeth 28 cut therein, the cylindrical portion being rotatably supported in the bearing 15. A smaller cylindrical portion 9 is receivable by a cylindrical portion 8 of the housing portion 7 of the handle 29,

which is provided with the elongated extension or lever portion. A washer 66 and a cap screw 67 are mounted by threading the latter into the threaded portion of chamber 68, the latterhaving an outlet 168 to bearing 15 for lubrication, which is supplied thereto byremoving the cap screw 67, llling the chamber 68 with cup grease and then replacing the cap screw 67.

Pivotally supported at 30-see Figs. 4 to 6 inclusive, on the handlel and in the housing 7 thereof..

is a pawl 31 which mounts a pin 59 that is an actuating member and also serves as a stop or anchorage for a spring 32. The other end of the spring engages the adjacent wall portion 7 of the handle and the spring 32 is coiled about the pivot 30. The pawl 31 includes an angular at spring extension 34 which is apertured as at 36 to' receive the offset end 135 of rod 35.

The rod 35 is reciprocated by nger lever 37 pivotally supported adiacent the end of the handle lever as at 40and by ears formed on the handle. Lever 37 includes an arm 39 which isassociated with the angular end 38 of the rod 35, so that when the member 37 is depressed toward the handle, the rod 35 will be projected toward the bearing 8, whereupon the offset portion 135 at the end of the rod 35 adjacent the spring aperture 36 will bend the spring before tilting occurs of the pawl 31 counterclockwise or radially outward from the ratchet teeth 28, providing there is a load upon the pawl. y

Therefore, this arrangement prevents dropping of ythe load so that the handle control in this respect is foolproof. If noloadl is on the ratchet tooth 28 then the pawl 31 is relieved from it Joy-the actuation of rod 35, since spring 34 is slightly stronger than spring 32. It is to be remembered, however, that` movement of the pawl 31 also moves' the actuated pin 59 and reference thereto will be made later.

Slidably and rotatably mounted in the handle housing 7, see Fig. 4, is a shaft having the exposed knob or handle portion 81 and an enlarged cylindrical portion 82. portion 82 and the housing, there is mounted a coil spring 84 that normally retains the shaft in predetermined position, that is the knob 81 is positioned close to the handle. The cylindrical portion 82 terminates in a shoulder 85. An angular plate 86, see Fig. 9 forms a partial closure for the handle supported mechanism and is provided with an opening 86a forming a bearing for the free end 87 of the shaft 80, see Fig. 9. The end 87 projects beyond the plate 86 and normally engages, at the end of arcuate movement upon either side of the housing, the abutments 88 thereof. W'hen the shaft 80 through the knob 81 is retracted from the full line position in Fig. 4 to the dotted line position shown therein, the end 87 of said shaft is retracted sufficiently to clear the adjacent shoulder or abutment 88 and permit the handle to be moved beyond the center and to the other side of the housing. Plate 86 terminates at 186 to expose pin 59.

In addition to this selective positioning lock arrangement, the shaft 80 also is arranged to control the pawl 31 and obtain the same operation as actuation of rod 35 obtains therewith. This is accomplished by the pivotally supported U-shaped spring that is pivotally supported at 89 on the rod and includes the oifset portion 90 and the bent end portion 91 that extends through the slot 92 in the leaf spring 34 before mentioned. Retractile movement of shaft 80 causes counterclockwise movement of pawl 31,`reference being had to Fig. 4, because the angular or offset portion 90 of the retractile spring bears upon the spring 34 and full retractile movement of the shaft 80 secures greater throw of pawl 3l than can be obtained by actuation of Vlever 37 and reciprocation of rod 35. The purpose of this additional throw of the pawl will be set forth more specifically hereinafter.

Extending into the housing is a shaft 101. The exposed end thereof carries a finger piece '44 whereby the shaft may be reversely rotated. The housing exposed end of the shaft includes an eccentrically positioned pin or cam member 42 which is operatively associated with the so-called reversing ring construction. When member 44 is positioned as shown in Fig. 2, the cam is in its lowest position andthe hoist is arranged for step-by-step lowering of the chain. When positioned as shown in Fig. 3, or the highest position, the hoist is arranged for step-by-step elevation.'

Reversing ring construction The plates are spaced by the three pin portions- 100 and secured together thereby. y The ring structure is shown in detail in Figs. 2 and 3. Plate 48 includes a segmental projection 46 having an arcuate periphery 46a which cooperates with pin 59 of the handle, as hereinafter set forth. Diaxnetrically opposite projection 46 is a similar projection 146 having a radial face 56 which also cooperates with pin 59 in the Between the cylindrical 1 Y ture.

handle. Arcuate face 46a through pin 59 maintains pawl 31 out of engagement with ratchet teeth 28. Engagement of face 56 with pin 59 serves to rotate the reverse ring structure in opposition to springs 45 secured at 45a to pins on the hoist body and secured to the ring at the spacing pins 100. An additional spring 47 is secured at one end to the third pin 100 and at its opposite end to a lateral extension or arm 26 of the shaft 22 carrying pawl 23. When shaft 101 is turned to the upward position-see Fig. 3- the cam pin 42 rotates the reversing ring which puts' tension on spring 47 and this is transmit- 'ted to sprocket pawl 23 causing same to engagein the sprocket teeth 17 to the hold load and chain while the handle is reversing for additional movement. f

Arm 26 of the shaft 22 is adapted to be engaged by pin 41 on the reversing ring structure. The movement of the reversing ring is limited by certain stops.

In elevating the hoist operation has a straight ratchet arrangement and the reversing ring is prevented from rotating, although constrained by the springs to rotate, by the shoulder 348 on plate 148, said shoulder engaging the eccentric pin 42 on the shaft 101. The same stop action is ob-. tained when the hoist is conditioned for reverse movement. Reverse movement of the reversing ring when the hoist is conditioned for lowering, is limited by the stop 33 on the housing, engaging the handle when the handle is positioned on the left side of the hoist. This is because pin 59 engages shoulder 56 and carries the ring with it until the handle engages the aforesaid stop 33. When the handle is positioned on the rightside of the hoist, reference being had to Fig. 2, this same movement of the reversing ring is limited in the aforesaid direction by the pin 59 on the handle engaging shoulder 248 on the ring and the shaft 87 in the handle engaging the right hand housing shoulder 88.

The plate 148 includes the segmental portion 148a merely to prevent cooking of the ring struc- 'Ihe opposite segmental portion, as previously set forth, has the shoulder 348. Plate 148 opposite the portion 148a in addition to providing the shoulder 348 engageable by the eccentric pin 42, is out away as at 148b for clearance, providing a slot or arcuate groove in which isv mounted the projecting end 22 of the shaft carrying the sprocket tooth engaging pawl 23. The arm 26 thereon overlies the plate 148 and lies in the space between the two plates 48 and 148, thereby insuring proper clearance. 1t will also be observed that this spaced plate structure provides protection for the springs 45 and 57.

The aforesaid, therefore, clearly sets forth the departure from the disclosures in the before mentioned application, so far as structure is concerned, and points out the simplicity of the present structure. 1t is to be observed that in common with the disclosure o f the before mentioned application, spring 47 as well as spring 24 are cooperative so that in the event of failure of spring 47, or the failure of spring 24, the pawl 23 will still be operative, and either might still be dispensed with, but for safety both are provided. In' the event either or both springs 4 5 fail, spring 47 is a supplementary thereto also,

rIhe flat spring 25 in common with the disclosure of the before mentioned application is adapted to yieldingly retain the eccentric pin 42 inv the predetermined controlling position that is for raising or' lowering. For this purpose, the shaft 101 has two at faces 63 and 65. This spring, how- In the rotation of the lever handle 29 to elevate the load step by step, the eccentric pin 42 is positioned as shown in Fig. 3. The load sustaining pawl 23 oscillates into and out of sprocket tooth locking position, while the load is carried by the spindle and through it the pawl 31 by the handle through the pawl 31 engaging in the ratchet teeth 28. Upon reverse handle movement, spring 24 and/or 47 causes the pawl 23 to seat between two teeth of sprocket 17, holding the latter against rotation in one direction.` The pawl 31 together with the handle 29 is then reversely rotated until pawl 31 engages another ratchet tooth 28 in substantially the initial position of the handle. In reversing, to lower the load, the nger piece 44 is positioned as shown in Fig. 2, which lowers the eccentric pin 42 and releases the tension on springs 45 and 47.

For reversal of the chainthrough the hoist when there is no load thereon, for so-called free chain movement, and in the lowering position, the reversing ring is rotated counterclockwise by the springs 45 and 47 until the pin 41 engages arm 26 of the shaft 22 and tilts the shaft to move the pawl 23 out of locking position with respect to the sprocket teeth 17. The chain may then be pulled downwardly through the housing. Since this hoist is in elevating of the so-called straight rigid type, if there is no load on the chain, it can be readily run through the hoist by the respective locking mechanisms ratcheting and permitting such action.

VFor elevating step by step, the operation is of the simple straight ratchet type, to wit, the handle 29 with the pawl 31 engages the ratchet teeth 28 and rotates the ratchet and with it the sprocket 17 and the locking pawl 23 rides into and out of the respective teeth and carries the load during the interval that the handle is not.

advancing for elevation and holds the load while the handle is reversed for positioning.

To lower the chain step by step with the load on it, the nger piece 44 is positioned as shown in Fig. 2 and the reversing ring is thereupon rotated counterclockwise.

When load is taken on handle with pawl 3l engaged in ratchet tooth 28, then pin 41 on the reverse ring contacts arm 26 and moves pawl 23 out of sprocket tooth 17 or locking position. The clockwise movement of the handle with load causes pin 59 on pawl 31 to contact with face 56 and retards pin 41 putting tension on spring 47 which pulls pawl 23 into locking position. After pawl 23 has taken the load, face 56 is still in contact with pin 59 on pawl 31 and by the tension of springs 45 and 47, pawl 31 is raised out of ratchet teeth 28 and the handle is lowered to take the load on the next ratchet tooth. After a short distance counterclockwise of the handle, pin 59 on pawl 31 leaves face 56, allowing pawl 31 to engage into the next ratchet tooth 28. mally self locking, hence the requirement for slight reverse v'tilting thereof to free it of the locking action before it can be fully tiltedout of sprocket tooth release position. When the chain is under load and it is desired to secure free chain action (equivalent to, dropping the The draft on pawl 23 is such that it is nord load), it is necessary to actuate member 81 to clear portion 82 from the path of portion 131 of pawl 31 and to actuate member 37 and rod 35 to tilt the pawl 31. In other Words, when the hoist is under load and member 37 with rod 35 is actuated, spring 34 will bend but the pawl 31 will not release from the ratchet teeth because portion 131 is limited by the portion 82 and full pawl movement cannot occur and thus accidental dropping of the load is prevented should the member 37 be actuated. However, if it is desired to drop the load, the member 37 may be actuated and the member ,81 must be pulled out to the dotted position shown in Fig. 4.

The invention claimed isz- 1. In a chain hoist the combination of a housing, a lever handle, a stop on the housing preventing complete rotation of the handle, stop means on the handle positioned oppositely from the first mentioned stop, and retractile means upon the handle `normally projected for second mentioned stop means engagement, said retractile means when retracted permitting handle pothe pawl, an arm carried by the 'pawl, a lever sitioning upon either side of housing for right or left. hand lever handle operation.

2. In a chain hoist the combination of a housing, a lever handle normally arranged for less than 180 of operative movement, stop means limiting the handle to such movement upon either side of the housing, and means arranged to permit the handle to move from one side to the other and vice-versa but preventing complete rotation of the handle.

3. In a reversing chain hoist, the combination with a sprocket tooth engaging pawl, a shaft therefor, a rotatable sprocket coaxial reverse ring structure including a pair of spaced plates, an eccentric cam, and means normally constraining the structure toward one position, one of said plates including a pair of segmental portions substantially oppositeeach other, the other of said plates including a shoulder angularly oifset from an adjacent segmental portion for cam engagement and a cut away portion for shaft clearance, and means operatively connecting the ring stmoture and shaft for the purpose set forth.

4. In a reversing chain hoist, a handle, a ratchet engageable pawl pivotally supported on the liandle, a hoist control operating portion carried by the pawl, an arm carried by the pawl, a lever operable rod for tilting the arm for pawl tilting, means opposing the tilting, an axially movable member, and a tiltable lever carried by the member and associated with the arm for tilting thereof by. the axial movement of the member.

5. In a reversing chain hoist, a handle, a ratchet engageable pawl pivotally supported on the handle, a hoist control operating portion carried by operable rod for tilting the arm for pawl tilt--l ing, means opposing the tilting, an axially movable member, and a tiltable lever carried by the member and associated with the arm for tilting thereof by the axial movement of the member, the amount of pawl movement being greater with the member movement than with the rod. movement. i

6. In a reversing chain hoist, a handle, a ratchet `engageable pawl pivotally supported on the handle, a hoist control operating portion carried by the pawl, an arm carried by the pawl, a lever operable rod for tilting the arm for pawl tilting, means opposing the tilting, an axially movable member, a tiltable lever carried by the member and associated with the arm for tilting J'ent accidental return movement of the member.

'7. In a reversing chain hoist, a handle, a ratchet engageable pawl.pivotally supported on the handle, a hoist control operating portion carried by the pawl, an arm carried by the pawl, a lever operable rod for tilting the arm for pawl tilting, means opposing the tilting, an axially movable member, a tiltable lever carried by. the member and associated with the arm for tilting thereof by the axial movement of the member, the amount of pawl lmovement being greater with the member movement than with the rod movement, a shoulder on the member, and a projection on the pawl larranged to engage the shoulder when the member is moved axially Y sufficiently to prevent accidental return movement of the wmember. v

8. In a reversing chain hoist, a handle, a ratchet engageable pawl pivotally supported on the handle, a hoist control operating portion carried by the pawl, an arm carried by the pawl, a lever operable rod for tilting the arm for pawl tilting, means opposing the tilting, an axially movable member, and a tiltable lever carried by the member and associated with the arm for tilting thereof by the axial movement of the member, said Opposing means tending to axially return said member.y

9. In a reversing chain hoist, a handle, a ratchet engageable pawl pivotally vsupported on the handle, a hoist control operating portion carried by the pawl, an arm carried by the pawl, a lever operable rod for tilting the arm for pawl tilting, means opposing the tilting, an axially movable member, and a tiltable lever carried by the member and associated with the arm for tilting thereof by the axial movement of the member, the amount of pawl movement being greater with the member movement than with the rod movement, said-opposing means tending to axially return said member.

10. In a reversing chain hoist, a handle, a ratchet engageable pawl pivotally supported on the handle, a hoist control operating portion carried by the pawl, an arm carried by the pawl, a lever operable rod for tilting the arm for pawl tilting, means opposing the tilting, an axially movable member, a tiltable lever carried by the member and associated With the arm for tilting thereof by the axial movement of the member, a shoulder on the member, and a projection on the pawl arranged to engage the shoulder when Athe member is moved axially suiilciently to prevent accidental return movement of the member,

said opposing means tending to axially return said member.

l1. In 'a reversing chain hoist, a handle, a ratchet engageable pawl pivotally supported on the handle,.a hoist control operating portion carried by the pawl, an arm carried by the pawl, a lever operable rod for tilting the arm for pawl tilting, means opposing the tilting an axially movable member, a tiltable lever carried by the member and associated with the arm for tilting thereof by the axial movement of the member, the amount of pawl movement being greater with the member movement than with the rod mov nent, a shoulder on the member, and a prcmction on the pawl arranged to engage the shoulder when the member is moved axially sufciently to prevent accidental return movement of the member, said' opposing means tending to axially return said member. A

12. In a reversing chain hoist, a handle, a

l ratchet engaging pawl pivotally supported on the handle, a control operating portion carried by the pawl, an arm carriedl by the pawl, an axially movable member, a tiltable lever carried by the member and associated with the arm for tilting thereofl by axial movement of the member, and means opposing the tilting of said pawl.

13. In a reversing chain hoist, a handle, a

ratchet engaging pawl pivotally supported on.

the handle, a control operating portion carried by the pawl, an arm carried by the pawL'an axially movable member, a tiltable lever carried by themember and associated with the arm for tilting thereof by axial movement of the member, means opposing the tilting of said pawl, said opposing means tending tc axiallyA return said member.

14. a reversing chain hoist, a handle, a ratchet engaging pawl pivotally supported on the handle, a control operating portion carried by the pawl, an arm carried by the pawl, an axially movable member', a tiltable lever carried by the member and associated with the arm for tilting thereof by axial movement of the member, means opposing the tilting of said pawl, a shoulder on the member, and a projection on the pawl arranged to engage the shoulder when the member is removed axially sufficiently to prevent accidental return movement of the member.

15. In a reversing chain hoist, a handle, a

vratchet engaging pawl pivotally supported on FREDRICK W. COFFING.

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