US2608107A

US2608107A - Puller device

Info

Publication number: US2608107A
Application number: US166451A
Authority: US
Inventors: Erford E Robins; Humphrey F Parker
Original assignee: Columbus McKinnon Chain Corp
Current assignee: Columbus McKinnon Chain Corp
Priority date: 1946-11-13
Filing date: 1950-05-02
Publication date: 1952-08-26
Anticipated expiration: 1969-08-26

Description

A g- 6, 1 E. E. ROBINS ET AL PULL-ER DEVICE 5 Sheets-Sheet 1 Original Filed Nov. 13, 1946 J-zz 12' .36 40 44 /00 INVENTORS A Par/fer 'ATTOR/VEYI 26, 1952 E. E. ROBINS ET AL 2,608,107

FULJJEIR DEVICE Original Filed Nov. 15, 1946 5 Sheets-Sheet 2 66 mzgff 76 BY QW,MM

ATTORNEY)" Aug- 26, 1 E. E. ROBINS ET AL FULLER DEVICE I5 Sheets-Sheet 3 Original Filed Nov. 13, 1946 Patented Aug. 26, 1952 -PULLER DEVICE Erfo r d E. RobinaNprth Tonawahda, and-Humphrey F. Parker, Bufialo, N. Y.,' assignors'" to Columbus McKinnon Chain Corporation, TonawandaN. Y.

: Original application November 13, 1946, Serial .No."709,506.j;Divi det1 and this application 2, 1950, Serial No. 166,451

Claims. (Cl. 74578) invention relates to lever op atedfor' socalled r'atehet hoists and pullersflsuch' asare" manually operated for raisin'g andflowering" loads, orfor tensioning'wires or cables; 'or apply? ing pulling-loads in any industry"; andthis ap-'-' plication is "a divisionf'of application Serial No.

709,506; new Patent N0.2 ,519,400. I

Specifically, the invention relates to improve-Q ments in the general type of hoist or puller such as is shown in, U. S. Patent No. 2,243,36l'; and wherein it"i'sarranged that wheneveri'the load is not being taken directly by the operating lever the load is sustained by the frame of the device independently of the operating lever by reason of automatic operation of friction brake means.

One of the objects of the invention is to provide a hoist or puller of the character described which embodies structural features enabling the device to be designed into more compact andspace-saving form. Another object ofthe invention is to provide in hoists or pullers of the character described an improved method of' relative assembly of the operating portions. Another object of the invention is to provide in a hoist of the character described an improved bearing arrangement for operative parts thereof.

Another object of the invention is to provide in a hoist or puller of the character described an improved ratchet control arrangement.

Other objects of the invention will appear from the specification hereinafter.v

In the drawing:

Fig. 1 is a sectional view through a puller of the invention; Fig. Zis a section taken along Fig. 1; and

Fig. 3 is a section taken along'line lI1I'III of 0 Fig. 1.

In the drawings the hoist or, puller of the invention is illustrated to comprise a frame l0 mounting a support hook l2 by means of a wash er and nutconnection device I4, as is conven-j tional in the hoist art. The frame l0 carries bearings l6i 8 in which are journalled the hoist load lift wheel shaft. This shaft includes a reduced portion 20 disposed within the bearing 16; an enlarged portion 22 disposed within the larger diameter bearing I8; a lift Wheelportion 24; a face plate portion 26; and an opposite re: duced end portion 28. The bearing l 6 ,is set against a shoulder 29 of the frame structure to transmit end thrust loads thereagainst. and

thus the lift wheel '24 transmits end thrust loads directed toward the left as viewed in Fig. .1 to the bearing IS. The shaft and bearing receiving hoist or line n41 of.

opening portions of the frame ID are so dimensioned that the bearing and shaft elements may be progressively assembled upon the "frame by' slip-fitting the parts into the frame from right-to left as' viewed in Fig. 1."

The extreme left end portion ofthe-shaft is grooved as indicated at 30, and a U-shaped bracket 32 is bolted to the frame as by means of a stud 34; one end of the bracket -32 being thereby disposed within the groove portion *of' the shaft to prevent accidental disassembly'of the shaft from the frame. The other end of the bracket 32turns upwardly into the centrally grooved portion of the lift wheel element 24 to function as a chain strippen asis well known in the hoist art. a

Afriction disc 36 is rotatably mounted upon the shaft. end portion 28 next adjacent to the face plate portion 26. 'A'ratchet wheel' lfi is' rotatablymounted upon the shaft portion 28 by means of a wear-resistant bushing- -42-;{and

second friction disc 44=is-rotatably mounted upon" the shaft portion 28 next adjacentto theratchet wheel 40; A lever ratchet "hub i6-is-rotatably mounted upon-the shaft portion 28' and carries therewith a ratchet wheel portion 48. which is externally toothed as indicated-at 56.. The.

ratchet'hub 4 6 has formed integrally therewith apair of helicallyshaped surfaces 5254, and a brake cam 56 having similarly helically shaped.

surfaces 58-69 is-mounted adjacent the outer end" of the-shaft portion 28 and keyed thereto aslat 60; "The cam surfaces 52-54 58'--59 are arranged so that the hub and. 'cam' members 46-56 are complementary at the surfacesof con tact therebetween, and whereby'relative'rotational movements 1 therebetween will force the ratchet hub 46 to be displaced axially relative to the cam 56. The'brake cam 56 is axially positioned and locked'against movement toward the right as viewed in Fig. 1 relative to the shaft28 by means of a threaded nut 62 and cotter pin 64.

A cover plate'66 is bolted by means of screws 6868 to the lever ratchet member 40- so as to enclose the'mechanism subsequent to-assembly thereof. .A second cover plate 61 is press-fitted into the opposite end of the housing to enclosethe latter.

' The lever. ratchet hub' and ratchet wheel; unit 46',48 is encircled by an annular wear-resistant bushing 69 about which is'cast the hub portion of the hoist operating lever 10; and as'illustrated in Fig. 2, the lever 'lfl carriesa plunger 12 which is normally biased by means of, a compression spring "so as to move at its toothed endpor- 3 tion 16 into meshed engagement with the ratchet wheel 48. The tooth portion 16 of the plunger 12 is so shaped as to cooperate with the ratchet wheel 48 to block relative movement of the lever and the ratchet wheel 48 in one direction, while permitting the ratchet wheel to cam the plunger 12 out of blocking position for rotation of the lever 10 in the opposite direction. However, the plunger I2 is arranged to be manually reversible in attitude, and for this purpose is provided with a laterally bent finger titl -whereby the operator may withdraw the pawl and rotatethe finger through 180, and then upon release of the pawl it will reengage the wheel 48 so as to block movement of the lever. relative to the ratchet wheel in the opposite direction.

j members"46-56' will cause the hub 46, together The lever frame I0 is recessed as indicated at 82 and the finger portion 80 is formed with a boss 84, whereby whenever the plunger 12 is in springbiased position the recessand boss formation 8284 cooperate to lock the lever against rotation. However, the finger Bilm'aybe manually retracted against the action of the spring Hand then only partially rotatedso as to cause the boss portion 84 to ride upon the outer shoulder of the recessed portion 82, to hold the pawl out of engagement. I

The frame Ii! carries a boss portion Etextending radially therefrom (Figs. 2-3); the portion 86 being radially bored toreceive in slip-fitted relation a cylindrical shaped pawl member 88. The outer end of the pawl 88'is shaped with a finger portion 90 for convenient gripping by .the operator. The pawl portion 90 is transversely slotted as indicated at 92 and is centrallybored as indicated at 94to accommodate therein a-compression spring 95 bearing at its inner end against the inner closed end portion of the pawl 88; Subsequent to mounting of the spring 95 withinjthe pawl cylinder, a pin-98- is slip fitted through registeringopenings in the-body portion 86 so as to bridge the bored portion of the pawl 88 and to provide an anchor for the outer end of the sprlng 95. Thus, the spring is arranged to resist withdrawal of the pawl 88-from engagement with the ratchet wheel; The bodyportionjii is formed with a pair of outstanding abutments 98+ over which theslotted-portion 92 of the pawl head 90' slip-fits in one position of the pawl cylinder; but upon manual withdrawal of the pawl from engagement-with the wheel 48 the pawl-member may be twisted so that the enlarged head 90 rests upon the outer ends of'the' abutments 98-98; whereby the pawl is with held from engagement. I I I The operation of the hoist or puller of the invention may be described as follows: Preliminary to hoisting or pulling against a'load. the hoist device is hung by means of the hook [2 upon some stationary anchor means at such position that it will beconvenient to manipulate thelever 18 with oscillatory motions, and with the load chain 99 extending therefrom into connection with the load. It'is then usually desirable to take the slack out of the loadchain' prior to levering. the handle Ill, and this is accomplished by withdrawing the ratchet control elements 8090 from engagement with 'thei'r're spective ratchet wheels, and rotating-them' slightly so that they rest upon the adjacentabutmentsl so as to be held out of engagement withth'eir' ratchets. This permits theope'ratingshaft 2D to be freely rotated so that'the free end of the load: chain may be simply pulled upon to rotate'the load lift wheel unit of the mechanism and to take with the ratchet wheel 48 and the friction discs 36-44 to'be forced endwise toward the left as viewed in Fig. 1 and into mutually pressure bearing relation against the face plate portion 25. This will cause the friction surfaces to become engaged so as to force the load lift wheel portion 24 of the shaft to rotate along with the lever 10; and the friction between the brake elements will be sufficlenttosustain the load when the operating handle 10' is being moved backwardly intermittently. of each pulling stroke thereof; Thus, the handle"!!! is simply oscillated back and forth until the load has been moved to the desired position, while at all times the load is frictionally sustained because of the fact that the ratchet pawl 88 is in engagement with the teeth of the Wheel 40, thereby preventing its movement backwardly when the load is not being sustained by' the operating handle during backward move ments thereof.

When it is desired to lower or to relax the pull upon the load,-the ratchet pawl control finger 80 is withdrawn outwardly against the tension of the spring 14," and when the hub portion 84 has cleared the recess 82 the lever 80 is rotated through and then allowed to return again underthe action of the spring into pawl-meshing position. Thus, the pawllfi will be in engagement'with the wheel 48, but in reverse attitude. Oscillation of the handle 'lflwill now serve to opcrate the shaft 20 in the reverse direction and against the'friction produced by the brake elements. The first movement of the handle under these conditions will serve to loosen the frictional engagement of the brake surfaces sufiiciently to permit the operator to relax the pull upon the load. Since the lowering. of the load will, however, tend to turn the shaft'zll'and thereby'rotate the brake cam 56, the load itself will keep the frictional surfaces of the brake unit in engagement sufficiently to sustain the load. Thus, under I, these conditions the load is never carried by the handle but always by the brake unit, so that there is no tendency at any time for the handle to escape the grip of the operator and run wild." However, as an extra safety precaution, we prefer to form a handle stop abutment I00 extending from'the upper portion of the frame I0 into registrywith aboss portion I02 (Fig. 1) of the lever'lfl, so that the latter 'is prevented from rotating more'than 360 under'any condition of loss'of" control of the handle by the operator. This furtherminimizes'the opportunities for accident. The boss'l02 isrelatively narrow when viewed in side elevation (Fig. 2) and is located centrally'of the lever 10, whereby the lever 10 will havea permissible range of travel through substantially 360, instead of a substantially lesser range of travel as would be the case in event the stop-portion [08' were arranged to abut against a side wall portion of the lever'10". It willbe understood that the handle 10 need not be oscillated through any prescribed degree of I angular displacement to operate the device so long as successive teeth of the ratchet wheel 40 are engaged, and that it may be oscillated within any convenient segment of the permissible 360 range of movement.

The provision of the paired bearings 16-18 of different diameters in the frame l provides a straddling support for the load lift wheel 24 while at the same time facilitating assembly of the mechanism by permitting the operating unit to be slip-fitted into the frame from one end thereof and then retained against accidental disassembly by the retainer 32. This combination stripper and lift wheel shaft retainer 32 provides a simple and an effective device performing a double function and thereby provides a further advantage over previous designs; and the stop device I00 provides a simple yet efl'ective arrangement for increasing the factor of safety in operation of devices of this character. The steel bushing 69 bears upon the ratchet hub 46 and upon the ratchet wheel 48 at opposite sides of the ratchet teeth 50, and the latter are retracted to prevent them from scoring the hub of the lever 10. Thus, a durable two-part bearing for a the lever upon the brake unit is so provided as to remain stable and snug yet non-binding over long periods of service. The bushing 69 is knurled as at H so that when the handle is die-cast thereon a keyed bonding of the two parts is effected.

It will be understood that although only one form of the invention has been shown and described in detail, it will be apparent to those skilled in the art that the invention is not so limited but that various changes may be made therein without departing from the spirit of the invention or the scope of the appended claims.

We claim:

1. In a ratchet puller, a housing, a ratchet wheel rotatable within said housing, said housing having a boss portion thereof bored in a direction radially of said wheel, a ratchet pawl slipfltting within said housing bored portion and extending into meshing relation with said wheel, said pawl having an enlarged body portion at the outer end thereof adapted to rest upon the outer end of said boss portion, said enlarged body portion being transversely slotted from the outer end thereof, said pawl being longitudinally bored from the outer end thereof to a position short of the inner end thereof, said housing boss portion having a pair of outwardly extending abutment portions to provide a rest for said enlarged body portion when the pawl is actuated out of wheel engaging position, a pin bridging the space between said abutments and traversing said slot, and a compression spring nested within said pawl member and bearing at one end against the inner end of said pawl and at its other end against said pin.

2. In a ratchet puller, a housing, a ratchet wheel rotatable within said housing, said housing being bored in a direction radially of said wheel, a ratchet pawl slip-fitting within said housing bored portion and extending into meshing relation with said wheel, said pawl being transversely slotted at the outer end thereof, said pawl being longitudinally bored from the outer end thereof to a position short of the inner end thereof, said housing having an abutment portion extending alongside said pawl, said pawl having a radially extending shoulder adapted upon lifting of said pawl to ride upon said abutment, a pin extending laterally from said abutment and traversing said slot, and a compression spring nested within said pawl member and hearing at one end against the inner end of said pawl and at its other end against said pin.

3. In a ratchet puller, a housing, a ratchet wheel rotatable within said housing, said housing being bored in a direction radially of said wheel, a ratchet pawl slip-fitting within said housing bored portion and extending into meshing relation with said wheel, said pawl having an enlarged body portion at the outer end thereof, said enlarged body portion being transversely slotted from the outer end thereof, said pawl being longitudinally bored from the outer end thereof to a position short of the inner end thereof, said housing having an abutment portion extending alongside said pawl and slip-fitting within the transverse slot in said enlarged body portion, whereby to provide a rest for said enlarged body portion when said pawl is pulled outwardly and rotated about its longitudinal axis, a pin extending laterally from said abutment and traversing the transverse slot in said enlarged body portion, and a compression spring nested within said pawl member and bearing at one end against the inner end of the bore in said pawl and at its outer end against said pin.

4. In a ratchet puller, a housing, a ratchet wheel rotatable within said housing, said housing being bored in a direction radially of said wheel.

a ratchet pawl slip-fitting within said housing bored portion and extending into meshing relation with said wheel, said pawl being longitudinally bored from the outer end thereof to a position short of the inner end thereof, said pawl being transversely slotted at the outer end thereof, said housing having a pair of abutment .portions extending alongside said pawl, said pawl having radially extending shoulder means adapted upon lifting of said pawl to ride upon said abutment portions, a pin extending between said abutment portions and traversing the transverse slot in the outer end of said pawl, and a compression spring nested within said pawl member and bearing at one end against the inner end of the longitudinal bore therein and at its other end against said pin.

ERFORD E. ROBINS. HUMIPHREY F. PARKER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 406,935 Murphy July '16, 1889 1,132,436 Campus Mar. 16, 1915 1,355,418 Pedersen Oct. 12, 1920 ,365,892 Craver Jan, 18, 1921 1,781,936 Stoeltzler Nov. 18, 1930 2,204,119 Campbell June 11, 1940 2,221,101 Lefkowitz Nov. 12, 1940 2,512,755 Vosper June 27, 1950