US2283215A

US2283215A - Claw bar

Info

Publication number: US2283215A
Application number: US358947A
Authority: US
Inventors: Lane John Thorne
Original assignee: Individual
Current assignee: Individual
Priority date: 1940-09-30
Filing date: 1940-09-30
Publication date: 1942-05-19
Anticipated expiration: 1959-05-19

Description

'J. T. LANE CLAW BAR May 1 9,194;

3 Sheets-Sheet l Filed Sept. 30, 1940 May 1942- J. T. LANE 2,283,215

CLAW BAR I Filed Sept. 50, 1940 s Sheets-Sheet s WWW Patented May 19, 1942 UNITED STATES PATENT: QFFICE 7 2,283,215 I 1 CLAW BAR v John Thorne Lane, New Yo'rk, N.Y. Application September 0, 1940, Serial No. 358,947 9 Claims. (01. 254-44) f 4 This invention relates to a. claw bar, and is an improvement in that type'of claw bar disclosed in United States Patent No. 2,026,581 issued to me January 7, 1936.

Claw bars of the type here concerned are used especially on railroad right-of-ways in withdrawing spikes from cross-ties and also from creeper plates through which they are driven into the ties. These spikes become tightly fastened in position and often their heads become broken off. It is therefore difiicult to withdraw them. This is particularly true when the spikes are driven through a creeper plate, since'there is difficulty in getting a proper purchase upon the spike and to obtain a proper bearing surface as a fulcrum for the spike. These conditions also make it diflicult to properly engage the spikes so that when a prying action takes place the jaws of the structure willbite into the-sides of the spike and positively hold it. In the invention as disclosed in my formerpatent as above identified these results were obtained in a measure but in actual practice it was found that a new and novel arrangement of the parts would produce a different and better result. It has been the principal object of the present invention, therefore, to provide'a claw bar for use in'drawing nails and spikes from members into which they have been driven, which bar will positively engage the object to be withdrawn, will insure that it will be withdrawn in a relatively straight line and that the entire operation may be performed efliciently without imposing undue strain upon the various parts of the claw bar.

The present invention contemplates the provision of a claw bar' structure having a handle and a forked fulcrum head at the end thereof, between which a pair of gripping jaws are pivoted and are provided with contiguousfaces along their abutting edges and faces along the forks of the fulcrum head whereby a prying action on the handle will cause 'the jaws to swing toward each other at their gripping points and to positively engage and pull an object such as a spike when the handle is swung downwardly, the'said jaws being so pivoted as to impose the prying force upon the abutting faces of the members -parallel arms l4 and 15. The span of these arms Fig. 2 is anenlarged view in side elevation with parts broken away showing the fulcrum head of the claw bar and the jaws associated therewith.

Fig. 3 is an enlarged view in elevation as seen on the 1ine'33 of Fig. 2 and discloses the construction of the fulcrum head and the gripping jaws carried thereby.

Fig. 4 is a view in elevation and section as seen on the line 4-4 of Fig. 2 and discloses the gripping jaws in their normal position preparatory to gripping an object.

Fig. 5 is a view similar to Fig. 4 but showing the elements in their gripping position.

Fig. 6 is a view in transverse section through the fulcrum head and the gripping jaws as seen on the line 6-6 of Fig. 2, and shows the gripping jaws in their normal" position.

Fig. 7 is a View in transverse section through one of the gripping jaws as seen on the line 1-4 of Fig. 2 and discloses a transverse formation of the toe portion. j f

Fig. 8 is a view in side elevation showing the initial'position'of the clawbarin operation.

Fig. 9 is a view similarto Fig. 8 showing a position of the claw bar when gripping a spike and. pulling it, and indicating a further position in dotted lines.

Referring more particularly to the drawings,

I0 indicates ahandle of a claw bar with which the'pres'ent invention is concerned. The major portion ofthe length of the bar is cylindrical throughout and is here shown as having a point II at its outer end. The dimensions and the shape of the point .at the outer end are in accordance with the standardsof the American Railway Engineers Association. The other end of the bar'has a slightly enlarged square shank l2 to which is formed afulcrum head l3. This fulcrum headis bifurcated and has a pair of is materially greater. than the width of the shank I 2 of the claw bar, the outer faces 5 of the arms being parallel.- A crotch I1 is formed between the arms and is defined by a relatively square back wall l8 and a pair of vertically inclined faces l9 and 20 which oppose each other. As shown in Fig. 6 of the drawings the inclined faces l9 and 20 flare outwardly and upwardly from the bottom faces 2| of 'the'arms' i4 and I5 so that in verticalpsection the crotch is of a general V-shape with the side walls diverging upwardly and outwardly.

By reference to Fig. 2 of the drawings where a 7 side elevation of.thefulcrum head is shown, it will be seen that the lower face 2| of-the arms is substantially arcuate. It, however, comprises a toe portion and a heel portion. The toe portion is swung on an arc indicated at a in Fig. 2, the center of which are is at the front of the axis of the pivot pin 22 and thereabove. The heel portion of the face 2| is swung on a relatively short are indicated at b in Fig. 2, which is in the rear of the center of the pivot pin 22. The pivot pin passes through the two arms l4 and I5 at a point eccentric to the arcs of the fulcrum surface 2| of the fulcrum head. The location of the fulcrum point with relation to the fulcrum head has been determined in order to insure that when a prying action is produced the strain will be thrown rearwardly of the fulcrum pin and will not be imposed thereupon to shear it. This will be more fully explained hereinafter.

The forward edges of the arms 14 and I5 of the fulcrum head terminate in flat shoulder faces 23. The fiat back face l8 of the crotch IT is substantially in the plane of the center of radius a as shown in Fig. 2 of the drawings. Disposed in the crotch I! of the fulcrum head is a pair of gripping

jaws

24 and 25. One of these jaws is shown in side elevation in Fig. 2 of the drawings. Here it will be seen that it is mounted upon the pivot pin 22 and is formed with an arcuate lower face 25. This arcuate lower face is slightly concentric with the arcuate face 2| as described by the arc 11 indicated in Fig. 2, so that at the beginning of the prying action the faces 26 provide the fulcrum surface and in the concluding stages the faces 2| provide the fulcrum. The toe portion of the jaw has a lower surface 21 which is described by an arc c indi-.

cated in Fig, 2 of the drawings, which gives additional clearance when the gripping jaws are being set to grip the object to be pulled. The

I under faces of the gripping jaws continue in a slightly concaved portion 28 which terminates with the toe 29 of the jaw. The upper face of each of the jaws is represented by an arc 39 adjacent to the toe of the jaw and a relatively flat are 3! continuing upwardly and rearwardly to a point in the rear of the pivot pin 22. At this point a fiat back face 32 occurs on each jaw which, when the jaw is in its normal position, rests against the face l8 in the crotch ll of the fulcrum head. The back face 'of each of the gripping jaws is formed with a face 33 which' continues downwardly and forwardly to the arcuate bottom face 26. This gripping jaw is disposed normally at an angle to the face IE but if the jaw swings to its full fulcrum position the face 33 will abut against the face N3 of the crotch. In the face l8 at the end of the crotch and at a point near the arcuate heel face 2! of the fork is a bore 34. This bore is designed to receive a spring 35 which exerts a pressure against the end faces 33 of the

fulcrum arms

24 and 25 and tends to swing the gripping jaws forwardly and upwardly to their normal position with the faces 32 of the jaws abutting against the face H3 in the crotch. As shown in Figs.

'4 and 5, it will be seen that the spring 35 is on the median line of the two jaws and overlaps them so that pressure can be exerted on both jaws uniformly. The jaws are'shown in plan in Figs. 4 and 5. It will here be seen that they have parallel shanks 36 which extend rearwardly and into the crotch l1. These shanks have forwardly protruding portions which represent the toe 29 and are of a width sufiicient to overhang the ends of the

arms

24 and 25 of the ful- =crum head. This forms each of the ja s Wi h a laterally extending lug portion 31 having a back face 38 which will abut against the front face 23 of the fulcrum head when the jaws are in their extreme gripping position.

The side faces 39 of the jaws are inclined correspondingly to the faces [9 and of the arms, as particularly shown in Fig. 6 of the drawings. Thus, on relative movement of the fulcrum arms and the gripping jaws incident to a prying operation the faces will move along each other to force the gripping jaws together. The contiguous faces of the gripping jaws when viewed in plan are in three planes; portions 40 which stand normally parallel to each other, as shown in Fig. 4 of the drawings, portions 4| which stand normally at angles to each other to permit lateral movement of the jaws on the pivot pin 22, and

forward portions 42 which are at a substantial angle to each other and are undercut to receive the object 43 to be gripped. The length of the portions and 42 represent the length of the toes of the gripping jaws, and these portions of the toes are formed with opposing recesses 44 which form a cup-like portion to accommodate the head of a spike or nail to be withdrawn. These recesses are indicated in plan in Fig. 4 while they are indicated in section in Fig. 2.

In operation of the present invention the structure is assembled as shown in the drawings and the spring 35 acts to force the

jaws

24 and 25 forwardly by exerting pressure against the back faces 33 of the jaws at a point below the axis of the pivot pin 22. This it should be pointed out is opposite to the action produced in the structure shown in my Patent No. 2,026,581 where the spring exerts -a :pressure against the back face of the jaws above the pivotal axis and in that case tends to force the jaws to their rearmost position, at which time the jaws are separated. In that particular arrangement the toes of the jaws are not rigidly held and cannot be quickly placed in position with relation to an object tobe pulled. In the present instance the jaws are firmly held between the arms 14 and I5 and when the foot or toe of a workman is forced against the heel portion of the fulcrum, as indicated at 45 in Fig. 8 of the drawings, the inclined faces 42 of the jaws will be forced against the object 43 being pulled as they straddle this object. 'The initial position of the toes'of the jaws, therefore, is substantially as shown in Fig. 8 where the handle ll] of the structure will be inclined toward the work and beyond the vertical. As the jaws are forced forwardly by pressure upon the back of the fulcrum head, it is evident that these jaws may yield so that the crotch formed by the inclined faces 42 will be widened .to more firmly grip the object 43 to be withdrawn. After the spike or other object 43 has been properly gripped between the faces 42 of the crotch occurring between the gripping jaws, the handle 10 is swung in the direction of the arrow X, as indicated in Fig. 8, and this will cause the fulcrum head to swing on the pivot 22 in the direction of the arrow :1]. Attention has already been called to the fact that the inner faces l9 and 20 of the arms, l4 and I5 of the fulcrum head are inclined and that the outer .faces 39 of the

gripping laws

24 and 25 are oppositely inclined and bear against the faces l9 and 20, and that furthermore these faces l9 and 20 are longitudinally tapered as well as outwardly flaring so thattheir spacing apart at the forward edges is greaterthan at the rear edges, thus as the fulcrum head swings downping jaws and in advance of the pivot pin 22.

It should be here. explained that openings 46 through the pivot pin 22 are of greater diameter than the diameter of the pivot pin so that the jaws24 and 25 will have a desired amount of lateral movement and will be free to yield when pressure is exerted against their sides. Attentionis also directed to the, fact that swinging movement of the jaws around the pivot pin 22 or lateral movement with relation to the pivot pin is yieldingly resisted by the spring 35. When the lever arm swings in the direction of the arrow X and the fulcrum head l3 swings in the direction of the arrow y pressure will be exerted so that the crotch formed by the faces 42 of the gripping jaws will tend to contract and will bite into the sides of the article 43 being withdrawn, as indicated in Fig. 5 of the drawings. As this action takes place the fulcrum head will swing as shown in Fig. 9, and the rear faces 33 of the gripping jaws will approach the transverse face I8 of the crotch of the fulcrum head. At the same time the forward face 23 of the arms of the fulcrum head will approach the rear face 38 of the side lugs of the toes of the gripping

jaws

24 and 25. It will be evident that when the handle i0 is swung further downwardly from the po-' sition shown in Fig. 9 it will reach a point at I which the faces l8 and 33 will abut against each other so that the jaws and the fulcrum head will move as an integral unit, at which time all of the strain will be directly imposed upon these parts. Attention is also directed to the fact that since the lateral pressure between the arms24 and 25 of the fulcrum head and the outer faces 39 of the grippingjaws is exerted in advance of the position of the pivot pin 22 the pin will be relieved of any shearing strain.

By reference to Fig. 9 of the drawings it will be seen that since thefulcrum point on the bottom of the gripping jaws is initially in advance of the end ,of the fulcrum head, the handle of the structure may assume a substantially vertical position-and may be swung while exerting a very considerabl leverage in extracting the member 43.

In order to insure that the two jaws shall work,

in unison a pin 50 is provided and fitted into pockets 5| and 52 at the juncture of the faces 43 and 4| of the gripping

jaws

24 and 25. There is slight freedom of movement between the pin and its seat which makes it possible for the jaws to fulcrum laterally without binding and at the same time insures that the jaws will swing together and that they will simultaneously bite into the opposite sides of the article being gripped and pulled in the same plane so that a suitable gripping action will be obtained.

By reference particularly to Fig. 2 of the drawings it will be seen that initially the faces 26 of the gripping

jaws

24 and 25 bear against the object, providing a firm support for the tool in a prying operation, and that as the head of the tool swings rearwardly and downwardly the pressure will be transferred from the face 26 to the face 2| forming the heel of the head l3, thereby insuring that the final and extreme strain will be imposed directly upon the tool and that the jaws will be free to grip and bind the object being extracted. It will also be evident that due to this arrangement the pivot pin 22 will be substantially free of strain at the time when the time.

greatest force is being applied and that the gripping jaws will wedge themselves into a binda ing position. between the arms ofthe head at that Attention is directed to the fact that the faces 23 of the head of the claw bar swing under the faces 38 of the claws and thus support the claws in a manner to cause the structure to act as an integral unit and to relieve strainfrom the pivot pin 22. r V

' While the tool is here shown as being utilized in extracting a railway spike provided with a head it is to be understood that due to th gripping action of the 'tool it is possible to extract spikes or the like from which the heads have been broken or which have been partially disintegrated by oxidization or electrolysis.

fI'he invention here disclosed has tratedas being embodied within the construction of a claw bar.

hammers, nail pullers or any other structure requiring the use of a pair of gripping claw elements.

It will thus be seen that the structure here disclosed'provides improved, simple and effective means for withdrawing spikes and other objects into which they have been driven, and where by the article may be withdrawn in a substantially straight line so that the object from which it is withdrawn will not be damaged, and so that the article may be withdrawn with less effort.

While I have shown the preferred form of my invention as now known to me, it will be understood that various changes may be made in combination, construction and arrangement of parts by those skilled in the art, without departing from the spirit of my invention as claimed.

Having thus described my invention, what I claim and desire to secure by Letters Patent is l. A claw bar or the like including a lever arm,

a fulcrum head at the lower end thereof, said fulcrum head being bifurcated and having a pair of parallel arms, the lower faces of said arms being curved to provide an arcuate rolling fulcrum surface, 'a pair of gripping jaws disposed between said arms, means pivotingthem in position to swing back and forth in the space bejaws to swing downwardly and therefore inward-v ly toward their gripping position.

2. Same 'as 1, adding the following: and interen-gaging means cooperating between the jaws to cause them to swing in unison.

3. A claw bar or the like including a lever arm,

a fulcrum head at one end thereof, said fulcrum head being bifurcated to form two substantially parallel arms, the upper faces of which are sub stantially in the normal plane of the lever and the lower face representing an arcuate fulcrum' surface, the forward ends of the armsterminat ing in jaws having opposed oblique inner faces v and the rear portions of the arms terminating in curved heels, a pair of gripping jaws disposed between said arms and lying against said inner faces, the contiguous vertical faces of said gripbeen illus It will be recognized that the invention may be incorporated in the design of ping jaws being formed in two planes meeting along a substantially vertical fulcrum line whereby the jaws may swing laterally in advance and in the rear of said fulcrum line, means pivoting said jaws together and between the arms of the fulcrum head at a point in the rear of said lines of convergence and in a manner to permit the jaws to swing on the axis of said pivot and to swing laterally with relation to the convergent fulcrum line, pressure faces formed on the outer faces of said gripping jaws, contiguous pressure faces formed on the inner sides of the fulcrum head arms, the faces extending downwardly and inwardly, and yieldable means interposed between the fulcrum head and the back faces of the gripping jaws in a manner to swing the gripping jaws forwardly and upwardly between the arms of the fulcrum head.

4. Same as 3, adding the following: said jaws having toe portions which extend forwardly ofthe ends of the fulcrum arms and are raised with relation thereto as the yieldable means normally forces the jaws forwardly and upwardly.

5. Same as 3, adding the following: said jaws having toe portions which extend forwardly of the ends of the fulcrum arms and are raised with relation thereto as the yleldable means normally forces the jaws forwardly and upwardly, said toe portions being formed with opposing angle edges adjacent to their forward ends whereby a throat is formed into which an object to be gripped may seat, and which throat will close as the gripping jaws swing downwardly from their normal yieldingly held position.

6. Same as 3, adding the following: said jaws having toe portions which extend forwardly of the ends of the fulcrum arms and are raised with relation thereto as the yieldable means normally forces the jaws forwardly and upwardly, said toe portions being formed with opposing angle edges adjacent to their forward ends whereby a throat is formed into which an object to be gripped may seat, and which throat will close as the gripping jaws swing downwardly from their normal yieldingly held position, and means interposed between the two gripping jaws and cooperating therewith along the line of convergence of their faces whereby fulcrum movement may take place between the two jaws while causing the jaws to move in unison.

'7. A claw bar or the like comprising a lever arm, a fulcrum head at the end thereof, said fulcrum head being bifurcated and having a pair of parallel arms spaced apart to form a substantially fiat crotch face, thecontiguous faces of the arms being oppositely and upwardly inclined, the lower faces of said arms being formed by compound curved surfaces providing a forward relatively flat arcuate face and an arcuate heel surface, a pair of gripping jaws disposed between said arms and overhanging the ends thereof, said jaws having tapered faces complementary to the tapered faces of the arms and a back face formed with upper and lower surfaces, one abutting against the flat face of the crotch in the inoperative position of the arms and the other abutting against the fiat face of the crotch when in a gripping position, a pivot mounting said gripping jaws between the arms of the fulcrum head and whereby the jaws may swing within the fulcrum head and between the arms, toes formed at the ends of the gripping jaws and forming a V-shaped crotch between them to grip a spike or the like, the inner faces of saidgripping jaws each being formed with two fiat faces disposed at an angle to each other whereby when the jaws are together at one side of the juncture of said faces the toes will be spread apart and when the jaws are together at the opposite side of said juncture the toes will be forced together, the said movement being produced by swinging movement of the jaws around their-pivot and between the arms of the fulcrum head, the under faces of said jaws being arcuate and bearing a relation to the compound curved faces of the fulcrum head whereby upon initial prying movement the lever purchase will be upon the. forward relatively flat arcuate surfaces of the gripping jaws and in the final stage of the prying movement the fulcrum will be upon the arcuate. heel faces of the fulcrum.

8. Same as '7, adding the following: and means articulately associating the two gripping jaws whereby they may swing in unison around their common axis and may have free lateral movement as they swing.

9. Same as 7, adding the following: and a spring acting to urge the gripping'jaws forwardly and upwardly tending to move their toe portions together.

JOHN THORNE LANE.