US2165984A - Puller - Google Patents

Description

July 11, 1939.

c. SCHROEDER FULLER Filed June 22, 1955 3 Sheets-Sheet l INVENTOR lav 5 ATTRNEY y 11, 1939- c. SCHROEDER I 2,165,984

, FULLER 3.8hoets-Sheet 2 Filed Jhne 22, 1955 INVENTOR BY MM ATTORNEY July 1 3 c. SCHROEDER FULLER Filed June 22, 1955 3 Sheets-Sheet 3 y H 7 5 m 5 u w rfl z 1 6 a 2 ATTORNEY Patented July 11, 1939 PULLER Charles Schroeder, Philadelphia, Pa., assignor to The Yale & Towne Manufacturing Company, Stamford, Conn., a corporation of Connecticut Application June 22, I935, Serial No. 27,883

14 Claims.

This invention relates to a puller type of mechanism especially used for pulling wire or cable.

While pullers of this particular type have been developed in the prior art to a considerable extent, they have never fully answered commercial needs. I believe that I have made a very subsantial contribution to this seemingly rather well developed art.

In a puller of' the class described, the loads or wire tensions which are sometimes developed are very great. These loads must be held securely and without any slipping. At the same time, the holding means must be of such a type as to occupy but little space and permit of some flexibility or adjustment. It is even conceivable that the flexibility or range of holding adjustment must be greater than that permitted by an ordinary pawl and ratchet holding means.

The lifting in this type of mechanism is done by a lever arm of relatively great length, and any slipping in the holding of the load will apply the load to the arm, and will swing the arm through space. Needless to say, such swinging would at least mean the maiming of the operator of the puller under ordinary conditions. This further emphasizes the need for practically perfect load holding means.

While the length of the operating lever arm is I greatly relied upon for the mechanical advantage required in a mechanism of this sort, yet some gear mechanism is required in pullers adapted for the handling of heavy loads. For this purpose, I have devised a gearing mechanism and 'a particular type of casing for holding that gearing mechanism, so that while I am able to obtain the mechanical advantage required, I am still able to hold down the size of my unit to the limits required by commercial practice.

There are additional important features in my invention, such as the means for mounting the lever arm assembly relatively to the lifting shaft of my unit. The means for reversing the operation of the mechanism to release the load or tension, are also very important. The reversing should preferably be done independently of the load holding means and without manipulation of those means, in order that no possible release of the holding means take place so as to apply the load to the lifting lever arm, whereby to swing the arm as previously indicated. I have so conceived my puller structure that the reversing mechanism operates without releasing the holding mechanism, and so that the lifting lever arm.

is never required to assume the load while acting to release that load.

Further features of the invention reside in the arrangement of the casing, the arrangement of the load sheave or sprocket, the arrangement of 'a lifting hook supporting link carried by the casing, and the particular mounting of the various other parts. At this point, it will be emphasized that the puller of my invention was conceived only after much research and development, and that while I do utilize parts which may possibly be known in this art, those parts operate in a new and novel manner and are arranged in a new and novel manner relatively to my casing and other parts of the puller so as to operate most efilciently and with the perfection of operation which is required in an instrument of this type.

For a detailed description'of my invention, I shall now refer to the drawings. Fig. 1 illustrates a puller in which there is a direct lifting of the load hook. Fig. 2 illustrates a puller in which the lifting is done through an interconnected hook to increase the capacity of the puller. Fig, 3 is a partial section along the lines 3 and 3a of Fig. 6,

showing some of the internal mechanism of the I a section taken along lines 'l! of Figs.'3 and 6.

Figs. 8-13, inclusive, are perspective views of parts of my puller.

Referring now to Figs. 1 and 2, reference numeral l indicates the casing in which my pulling mechanism is mounted. A hook H supports the casing and is itself secured in swivelling re-' lation to the casing, as is best illustrated in Fig. 5, through means of a nut 12 maintaining portion l3 of the hook in bearing relation to the bearing I4 of the casing. In Fig. 1 the puller is shown as adapted to apply pulling power to a hook l5 supported by means of a housing l6 by a pulling chain I'I. In Fig. 2 the hook I5 is shown supported by a member |6a supported in turn by chain l'l through means of a hook 18. In this manner, a doubling of the capacity of the puller is possible, as will be clearly understood by those skilled in the art.

The hook I8 of Fig. 2 is in turn supported by a link member Hi. This link has portions forming an obtuse angle, one with the other, one of the legs of this obtuse angle being horizontal and cocupying a position between a hook 20 on the casing and lugs 2! on each side of the casing whereby the link is supported as is clearly illustrated in Fig. 2.

Referring now to Fig. 6, I will'describe the manner in which the chain 11 is operated for pulling in the hook l5. A. lifting shaft 25 carries thereon at one end a gear 26 whereby it is maintained in thrust bearing relation at 21 to the plate Illa of the casing ill, the particular end of the shaft 25 which supports the gear 26 being mounted for rotation on the bearing portion 28 of the plate la. The shaft 25 has a further bearing portion 29 which is maintained in hearing relation to the cylindrical surface lb of the casing. Keyed to the shaft 25 is a friction member 30 having-a sleeve portion 3i supporting the'key. A holding ratchet wheel 32 is loosely mounted on the shaft 25 and between this ratchet 32 and the friction member 30 there is located a friction disc 33. In addition, the shaft 25 has a screw threaded portion 34 on which is threaded the reversible ratchet member 35. A hand wheel 36 having a series of lug portions M, is supported against the reversible ratchet 35 .with its lug portions 3'! in the openings'w of the reversible ratchet 35, and is held in this position by a nut 39 threaded on the shaft 25. At this point, it should be emphasized that while I prefer to use the frictional binding arrangementillustrated, many other types may be utilized. For instance, the disk 33 could be dispensed with and a friction surface'could be applied to ratchet 32. Thus, while I claim one form of friction binding arrangement, other forms should be considered as equivalents in construing my invention.

The plate We of the casing together with part of the cylindrical surface separate the load shaft ll from shaft 25 and form a rather enlarged open casing portion 40 in which is maintained the central part of a load shaft M. The load shaft ll is mounted in thrust bearing relation to plate Illa of the casing by means of a gear 52 meshing with the gear pinion 26 on the shaft 25, and is maintained in the bearing 33 of the plate illa for rotation relatively to the casing. In the relatively large casing opening 40, the shaft 4i carries a sprocket 42a which might be a chain sheave, if a different type of chain is utilized. The end of the shaft 48 opposite to the gear carrying end is mounted in a bearing 44 integral with the plate lllc, a part of the shaft extending outwardly beyond the plate 800 and supporting thereon a load holding pawl 45 which pawl cooperates with the ratchet 32 carried on the lifting shaft 25.

The pawl 45 as shown in Figs. 1 and 2 has a bore 46 into which extends one end of the spring 41, the other end of which abuts a lug 48 on the outside of the casing and thus urges the pawl 45 into cooperation with the ratchet 32. In Fig. 8 I have illustrated in perspective the ratchet 32; in Fig. 9 I have illustrated in perspective the friction disc 33; and in Fig. 10 I have illustrated in perspective the friction member 30. In Fig. 13 I show a stripper member 41a bored out at 48a for cooperation with a bolt 49 best shown in Fig. 5, and thus maintained in a vertical position and in abutting relation to the load shaft 4|. The function of the stripper 41a is to maintain the chain l! in proper relation to the sprocket 42.

In Fig. 5 I illustrate quite well the relation between the portions of the casing and the mechanism therein, also the action of stripper 41a. In Fig. 6 I illustrate the geared relation between the gear pinions 26 and 42, the load shaft 4| and the lifting shaft 25.

. 'For applying lifting effort to the reversible ratchet 35 I utilize a handle assembly 56 havinga cylindrical portion 5| in which operates a reversible pawl 52 spring pressed by a spring 53 into coaction with the teeth 35a. of the reversible ratchet 35. The handle assembly 50 has a sleeve 5 portion 54 maintained in bearing relation to the wheel 36 by means of the bearing 55 on wheel 36, as best seen in Fig. 6. It will be seen that in this relation of the parts the sleeve 54 completely surrounds the reversible ratchet 35, the u pawl 52 extending from the cylinder portion 5| through the sleeve 54 into coaction with the teeth 35a of the ratchet 35.

The pawl 52 has a shaft extension 56 carrying a handle 51 which has a detent lug 53 operating u in a detent notch 59. Viewing the section of the parts 58 and 59 shown in Fig. 7, it will be seen that the handle 511 can not be rotated to reverse the pawl 52 until handle 51 is first operated to pull the pawl from coaction with the teeth 35a 2 against the spring 53 and from this point just slightly further to bring the lug 56 entirely outside the walls of the notch 59. Thereafter, the handle 5l may be rotated and the pawl reversed, and locked in its reversed position. While 1511625 pawl 52 may move freely against spring 53 in and out of the tooth outlining depressions of ratchet 35, this movement will be less than required to move lug 53 out of notch 53. I

The operation of my puller is as follows: When 3 it is desired to lift the load, the pawl 52 is properly positioned as shown in Fig. 3 by being pulled. outwardly by handle 51 and placed in its proper relation to the teeth 35a of the reversible ratchet 35. Should there be some slack in the chain l1, 3: this slack may be taken up by rotation of the hand wheel 35, this hand wheel being mounted for integral movement with the reversible ratchet 35 through its pins 31 resting in the openings 33 of the ratchet. The initial rotation of the 41 ratchet 35, either by the hand wheel 36 or lever assembly 50, will act through the screw threads 34 to bring it solidly against the ratchet 32, and wil1 force ratchet 32 solidly against the friction disc 33 and the friction member 30., Continued 4 rotation of the said ratchet 35 will cause rotation of the shaft 25 and the friction discs and the ratcliets 32 and 35 as a unit. This rotation of the shaft 25 will .of course operate through the gears 26 and 42 to rotate the load shaft 4|, 54 and through it the sprocket 42a. to pull in the chain l1 and hook I5.

Should pulling effort be withdrawn, it will readily be seen that there will be a tendency for the shaft 25 to rotate in a direction reversely to 51 that of the lifting direction, and counterclockwise as looking at Fig.3. This will of course force the reversible ratchet 35 solidly against the ratchet 32 and will bind the said ratchet 32 to the friction disc 33 and friction member 30 so as to 54 form in effect a single unit of the shaft 25 and the ratchet member 32. Since the ratchet member 32 is prevented at all times from movement in a counterclockwise direction, looking at Fig. 3, by the pawl 45, it will readily be appreciated n that the lifting shaft 25 will be held fixed and the chain 1 I be held against movement outwardly from the casing.

Should it be desired to permit an outward movement from the. casing of the chain II, it will 7( merely be necessary for the operator to reverse the direction of pawl 52 so that the pawl will be in a position to contribute counterclockwise movement of the reversible ratchet 35 in Fig. 3. With the chain held in fixed position as was 71 previously described, counterclockwise rotation of the reversible ratchet will tend to relieve the friction between ratchet 32, friction disc 33 and friction member 30. This will of course permit the shaft 25 integral with friction disc 30 to rotate in slipping relation to the ratchet 32 and permit an outward movement of the chain I'I. As soon as movement of the reversible ratchet 35 is stopped, the binding action previously described will once again take place and maintain the chain in fixed position.

From the description and the synopsis of the operation presented, it is easily appreciated that I am able to obtain an easy and effective pulling in of the chain by a compact mechanism; that my holding of the load is positive and yet flexible; and that my reversing operation is easy and simple and does not require the assumption of the load by the operator, nor any manipulation of the load holding mechanism with the inherent dangers involved in such manipulation.

I now claim:

1. In a puller of the class described, a lifting shaft, a friction disc having a sleeve portion keyed to said shaft, a second friction disc on said shaft juxtaposed to said first disc, a load holding ratchet loose on said shaft and juxtaposed to said second friction disc, a reversible ratchet next placed on said shaft and in screw threaded relation thereto, a hand wheel fixed to said reversible ratchet, a lever assembly rotatable relatively to said shaft and reversible ratchet, a reversible pawl carried by said lever assembly and cooperable with said ratchet, a load shaft in geared relation to said lifting shaft, and a pawl on said load shaft cooperable with said load holding ratchet.

2. In a puller of the class described, a lifting shaft, cooperative friction discs on saidshaft, 8. load holding ratchet freely rotatable on said shaft, a reversible ratchet screw threaded on said shaft and adapted to bind said friction discs and load holding ratchet, a hand wheel fixed to said reversible ratchet, a lever assembly having a sleeve portion maintained in bearing relation to said hand wheel for free rotation about said reversible ratchet and ,in covering relation thereto, and a reversible pawl on said lever assembly traversing said covering sleeve for engagement with said reversible ratchet.

3. In a puller of the class described, a lifting shaft, cooperative friction discs on said shaft, a load holding ratchet freely rotatable on said shaft, a reversible ratchet screw threaded on said shaft and adapted to bind said friction discs and load holding ratchet, a lever assembly having a sleeve portion a reversible pawl on said lever assembly adapted for engagement with said reversible ratchet whereby to rotate said ratchet, a hand wheel operatively connected with said reversible ratchet for rotating said ratchet independently of said lever and reversible pawl, and means for moving said pawl out of engagement with said reversible ratchet.

4. In a puller of the class described, a lifting shaft, a'friction disc having a sleeve portion keyed to said shaft, 9. second friction disc on said shaft juxtaposed to said first disc, 9. load holding ratchet loose on said shaft and juxtaposed to said second friction disc, a reversible ratchet next placed on said shaft and in screw threaded relation thereto, a hand wheel fixed to said rea reversible pawl carried by said lever assembly and cooperable with said reversible ratchet. I

5. In a puller of the class described, a lifting shaft, cooperative friction discs on said shaft, a load holding ratchet freely rotatable on said shaft, a reversible ratchet screw threaded on said shaft and adapted to bind said friction discs and load holding ratchet, a load shaft in geared relation to said lifting shaft, and a pawl mounted on said load shaft for cooperation with said load holding ratchet.

6. In a puller of the class described, a casing, a lifting shaft having a gear at one end and through which it is maintained in thrust relation to the casing while said end is in rotating bearing relation to said casing, a load shaft similarly mounted in the casing with its gear meshing with said first gear, a further casing portion supporting said lifting shaft and separating said lifting shaft from an enlarged casing opening occupied by said load shaft, 8. chain sprocket on said load shaft located in said casing opening, a load chain passing over said chain sprocket, the upper part of the casing forming said opening having secured thereto a hook for supporting said casing.

'Z. In a puller of the class described, a casing, a lifting shaft partially in said casing and partially out of said casing, a load holding ratchet on said shaft, a load shaft in said casing having a portion extending outside the casing, a pawl on the portion of the load shaft extending outside the casing, a lug on the outside of the casing, and a spring operating between the lug and pawl and adapted to press the pawl against the load holding ratchet.

8. In a puller of the class described, a casing, a lifting hook link retainer adapted to be supported on the casing, and a hook and a lug integral with said casing and cooperable with said link for maintaining the same in position.

9. In a puller of the class described, a casing, a lifting hook link retainer adapted to be supported on the casing, a hook and a lug integral with said casing, said link being arranged to underlie said hook and overlie said lug with its lifting hook retaining portion extending away from the casing.

10. In a puller of the class described, a lifting shaft, cooperative friction discs on said shaft, a load holding ratchet freely rotatable on said shaft, a reversible ratchet screw threaded on said shaft and adapted to'bind said friction discs and load holding ratchet, a hand wheel fixed to said reversible ratchet, a lever assembly having a sleeve portion, means whereby said lever through its sleeve is maintained for free rotation about said reversible ratchet and in covering relation thereto, and a reversible pawl on said lever assembly traversing said covering sleeve for engagement with said reversible ratchet.

11. In a puller of the class described, a lifting shaft, a load holding ratchet on said shaft, means for rotating said shaft, a load shaft in geared relation to said lifting shaft, and a pawl mounted on said load shaft for cooperation with said load holding ratchet.

12. In a puller of the class described, a lifting shaft, a friction disc keyed to said shaft; a second friction disc on said shaft juxtaposed to said first disc, 9. load holding ratchet loose on said shaft and juxtaposed to said second friction disc, a reversible ratchet next placed on said shaft and in screw threaded relation thereto, a lever assembly rotatable relatively to said shaft and reversible ratchet and in encompassing relation to said reversible ratchet, means whereby said lever assembly operates said reversible ratchet, a bearing support for said lever assembly secured on said shaft, said bearing support being adapted to support said lever assembly for rotation about reversible ratchet while confining said assembly between said bearing support and said load holding ratchet.

13. In a puller of the class described, a lifting shaft, cooperative friction discs on said shaft, a load holding ratchet freely rotatable on said shaft, a reversible ratchet screw threaded on said shaft and adapted to bind said friction discs and load holding ratchet, a lever assembly having a. sleeve portion, bearing means secured to said lifting shaft and supporting said sleeve portion for free rotation about said reversible ratchet, said bearing means confining said sleeve between said bearing means and said load holding ratchet.

14 In a puller of the class described, a lifting shaft, cooperative friction discs on said shaft, a load holding ratchet freely rotatable on said shaft, a reversible ratchet screw threaded on said shaft and adapted to bind said friction discs and load holding ratchet, a hand wheel for operating said reversible ratchet, and a lever assembly maintained for free rotary movement relatively to said shaft and reversible ratchet and carrying a reversible pawl for operating said ratchet.

CHARLES SCI-IROEDER.

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