US2613557A

US2613557A - Work holder

Info

Publication number: US2613557A
Application number: US78829A
Authority: US
Inventors: Lowell L Pricer
Original assignee: Individual
Current assignee: Individual
Priority date: 1949-02-28
Filing date: 1949-02-28
Publication date: 1952-10-14
Anticipated expiration: 1969-10-14

Description

L. L. PRICER Oct. 14, 1952 WORK HOLDER Filed Feb. 28, 194? Piras/2 3 AT1-ORN EY Patented Oct. 14, 1952 UNITED STATES PATENT OFFICE i 2,613,557 y y WOR-K HOLDER Lowell "L, Pricer, Hayward, Calif.

Application February 28, 1 949, Serial No. 78,829

7 Claims. 1

'This 'invention relates to a unitary `work holder adapted to positively and clampedly secure workpieces in place upon the bed 'of a drill rpress or othermachine tool.

An object of the present invention is the provision of a work holder which may be variously mounted with respectI Ato machine tools with which it maybe used.

Another object of the invention is'the provision of :a clamp finger of a work holder such that the same operative setting thereof can be established and maintained during work on a succession of like pieces.

A further object istoprovide aquickly actuatable clamping and releasing-meansfor the clamp viinger.

Yet another object of the invention isthe provision of a'work-ho'lding device of the `character which can be readily-swung out of the way during 4work-aligning operations, or when not in use, without the necessity of having to dismount it vfrom the machine tool which mounts it.

The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set Vforth or vvbeapparent in the following description of atypical embodiment thereof, `and in the accompanying drawings in which,

v-Iigurel is a planview-of a present work" holder, certainfparts being broken away.

'Figure 2 is a broken-away elevation of the :work-holder.

Figure 3 is a'longitudinal vertical section illustrating a typical working-application of the work holder.

Figure 4 isa section .taken on line 4--4 of VFig- Figure V5 is a 'fragmentary section'showing an alternate control means for a work-engaging nger of the holder.

Figure 6 is 'a sectiontaken on the line 6-6 of Figure 3.

its open side facing downwardly fromthe upper 2 lwall or web 'II of the arm. The armt extends integrally and radially 'from a split clampingcollar I2 having its lower end coplanar with the bottom edges of the sides I3 of the arm, and the collar l2 is split oppositely `of the arm I0 and is formed with usual lugs I4 radapted to be `drawn toward one another in `a clamping action of the Vcollar by means of a hand screw I5 extending through them. As particularly shown, theflugs I4 are engaged -between the screw head I6 and va nut I-'I vwhich non-rotatively engages' the lug I6 which is 'furthest from the screw head. f

The inner faces of each 0f the side vwalls-I3 of the arm I0 are formed at their outer end vportions with relatively shallow paralleland mutually opposed slots IB, said-slots extending inwardly from the extreme end lof the arm radially thereofand cooperatively providing a track or guide VVfor the reception-of the `ends of a iulcrum pin orlroller I9 engaged intermediately through a clamping finger 2li which has pivotal and longitudinally adjustable relationshipsto thearm. The finger 2-Ilextends forwardly beyond the arm I0 and terminates in a work-contacting. end portion .2|

which has its under'face offsetdownwardly and which is longitudinally forked from its forward "end to provide'for a more positive clampingaction by the finger and to also permit the straddling o'ffa drill, tap, or other rotary tool by the applied linger as illustrated inli'igures 3 and 8.

The inner end of the nger 2n is formed toprovide spaced coaxial eyes22 having their axis parallel to the pin I9 and rotatively mountingv a cylindrical member 23 provided with an intermediatetransverse threaded hole and in effect comprising a nut for use in a manner hereinafter brought out. A compression spring 24 is constantly operative between-the arm web II yancla point ofthe ilnger intermediate the nut 23 v4and Vthe fulcrum pin I9 to urge the disposal of the working end 2I of the nger 20 in its limiting fupper position, as indicated by solidlines in Figure.2. The spring 24 is retained initsloperative position-by having one end xed in a seat socket 25 provided in the top of the lever 20 and having its other end slidably engaging a seat comprising a relatively short and shallow longitudinal slot 2B -o`i`v uniform width provided in the under sideof the upper wall I I of the arm IIJ.

An elongated rectangular Opening -27 is provided'through and along the top wall II of the arm I0, and a covering plate member 28 is provided at the upper wall side for adjusted posi- Vtioning longitudinally of the arm I0 while in vbearing relationto the topof the arm. The plate 28 is provided intermediately thereof with a depending rectangular portion 29 which slidably ts between the sides of the opening 21 for restraining the plate to a solely longitudinal adjustment thereof. Rearwardly of the opening 21, the top of the arm wall Il is provided with a series of transverse and parallel depressions 30 for receiving a lip 3| which depends from the under face of the plate 28 at its rear end, whereby to provide for definite adjusted positoningsv of the plate along the arm. l i

It will now be noted that the plate 28 is located above the cylindrical nut 23 carried by the iinger 1 20, and rotatably mounts a finger-control member comprising a screw 32 passing slidably through a hole therein and having a lowerv` threaded portion engaging the nut 23 which is rockable as a wristpin when the screw is reciprocated. The upwardly projecting portion of the screw 32 has a cam lever 33 pivoted thereto by means of a fulcrum pin 33', the present lever 33 is forked from one end to straddle the projecting end of the screw 32, and the pin 33' passes through both sides 33 of the forked lever portion and is iixed therein whereby the pin is rotatable in a complementary transverse bore of the screw 32. A thrust washer 34 loosely receives the screw 32 and is arranged to have one face thereof bear against the top of the plate 28 while its opposite face is engaged by camming

faces

35 or 36 provided by the fork sides 33 of the lever 33, said faces being flat and making an included angle of substantially ninety degrees between them.

Referring particularly to Figures 2 and 3, it will be seen that the face 35 is closer to the axis of the screw 32 than is the face 36, whereby a swinging of the leverfrom its position shown in Figure 2 to its position shownin Figure 3 will result in a cam action between the cam face 36 and the thrust washer 34 to raise the screw 29 and the attached nut 23. This will cause a rocking of the finger 20 about the fulcrum pin I9 to move its working end 2| in a downward direction for exerting a positive clamping pressure against any workpiece which it may then contact. By adjustably rotating the screw 30 in an appropriate direction, the clamping and releasing positions of the cam faces of. the lever 33 can be adjusted relative to the surface of the work with which the finger 20 is to make operative contact, this arrangement making any further screw adjustment unnecessary when like workpieces are to be similarly worked on successively. Since the cam faces intersect at a line which is further from the., pin axis than the faces, the camming head of the lever 33 will tend to remain set in' either its operative or inoperative position.

An alternate means for controlling the nnger 2D is shown on the fragmentary section of Figure 5, wherein a hand-screw 3l replaces the screw 32 and the cam lever 33 to facilitate applications of the finger to differing workpieces, it being understood that the essential valueof the cam lever arrangement lies in the provision for successive like settings of the finger in a particularly speedy and accurate manner.

It will now be noted that the describedworkholding unit has been particularly arranged for use in fixing a workpiece against a vbed or table of a machine by which a rotary tool is advanced against a workpiece disposed on the bed or table. As illustrating a typical use of the present workholder, Figures 3 and 8 show the holder as operatively associated with a drill-press A having a base B, and a post or standard P xedly related to the base B and adjustably supporting a head H which provides a rotary tool T for application against a workpiece W supported from the bedplate B of the base B. In the present instance, the workpiece W comprises a tubular sleeve or bushing which is directly supported in a V-block V for the working application of the tool T (drill) radially against it; for descriptive convenience, an actual workpiece and any associated base member, as the V-block V, may be collectively considered a workpiece.

In the present drill-press structure, the post P thereof is cylindrical and is assumed to be of the appropriate size for its clamped engagement in the clamp collar I2 of the present unit whereby the unit may be directly mounted on the post in adjusted position therealong to dispose the finger 20 of the holder in position to span the drill T as the same is applied to a workpiece mounted directly on the base bed-plate B. When the present holder is mounted on a post P, the clamp screw l5 may be loosened to provide for swinging adjustments thereof over the bed-plate or displacement out of the way of the holder about the post.

Since, however, the head-supporting posts of various machine tools with which the present holder might be used may not be alike, means are preferably provided for mounting a present holder unit in operative position with respect to a machine tool independently of the post structure of a machine with which it is to be used. Accordingly, and as is illustrated in Figure 8, a mounting post 38 is provided on an auxiliary bedplate 39 which is in turn arranged to be mounted on or screwed to a machine bed-plate such as the bed-plate B of the present' machine A. The plate 39 may solely rest upon the top of the bedplate B', or be positively secured to the bedplate by C-clamps or by means of bolts engaging the conventional T-slot of such bed-plates. Figures 3 and 8 disclose the tubular workpiece W as engaged by a drill T while resting in the trough of the V-block V which stands on the bed-plate 39 supported on the bed-plate B. It will be understood that the combination of a present holder arm unit and the post 38 and the base plate 39 comprises a unitary positioning and holding clamp for the workpiece, and that the longitudi- Inal adjustment of the rockable finger Y2l) along the arm l0 which is permitted when the finger 20 is in operation, provides for the most efficient application of the finger to the workpiece for clampedly holding it fixed with respect to the plate 39 while providing for the application of a tool to the workpiece directly through or beside the forked end of the finger.

From the foregoing description taken in connection with the accompanying drawings, the advantages of the present work holder will be readily understood by those skilled in the art to which the inventiony appertains. While I have described the principle of operation, together with arrangements .which I now consider to be preferred embodiments thereof, I desire to have it understood thatv the showings are primarily illustrative, and that such changes and developments may be made, when desired, as fall within the scope of the following claims.

I claim:

l. In a device for clampedly holdinga workpiece against a bed-plate, an arm fixedly related to the bed-plate in spaced opposed relation thereto, a clamping finger directly and intermediately hinged to the arm and having a work- Engaging forward end swingable toward and from the bed-plate and having its rearward end disposed beneath the arm, a, wristpin journalled in the rearward end of the finger in fixed parallel relation to the axis of hinging of the finger and providing a transverse threaded bore, a control member threadedly engaged in the threaded bore of the wristpin and operative in tension between the top of the arm and the wristpin to clampedly engage the forward end of the finger with a work-piece disposed between it and the bed-plate, and means to reciprocate said control member in working and return strokes thereof.

2. In a device for clampedlyholding a workpiece against a bed-plate, a clamping iinger providing a work-engaging end and intermediately journalling a fulcrum pin having its ends extending laterally from the finger and xedly related to the finger, and arm xed related to the bedplate in spaced opposed relation thereto and providing a longitudinal rollway beneath its top and fittedly receiving the ends of the fulcrum pin of the finger for a longitudinally adjusted disposal of the finger therealong while the inner finger end is disposed beneath the top of the arm, and a control member operative in tension between the top of the arm and the underlying rear end of the finger to clampedly engage the workengaging end of the finger with a work-piece disposed between it and the bed-plate.

3. A structure in accordance with claim 2 wherein the iinger is disposed in a channel of the arm having its open side toward the bedplate and having its sides providing the rollway for its fulcrum pin.

4. In a device for clampedly holding a workpiece against a bed-plate, a clamping finger providing a forward work-engaging end and intermediately mountingv a fulcrum pin having its opposite ends extending laterally from the finger in xed relation thereto, an arm flxedly related to the bed-plate in spaced opposed relation thereto and providing a longitudinal guideway beneath its top and ttedly receiving the ends of the fulcrum pin of the finger for a longitudinally adjusted disposal of the finger longitudinally along the arm and from beneath its top, a bearing plate engaging the top of the arm and adjustable along the arm as the finger, said arm being provided with a longitudinally extending opening, a control member operative in tension between the bearing plate and the rear end of the iinger and extending through said top opening of the arm to clampedly engage the work-engaging end of the finger with a work-piece disposed between it and the bed-plate, and a spring means constantly and yieldingly operative between the rearward flange portion and the arm top to resist an operative action of the control means.

5. In a device for clampedly holding a workpiece against a bed-plate, a clamping finger providing a forward work-engaging end and intermediately mounting a fulcrum pin fixedly related to it and having its opposite ends extending laterally from the finger, lan arm iixedly related to the bed-plate in spaced opposed relation thereto and providing a longitudinal guideway fittedly receiving the ends of the fulcrum pin of the finger for a longitudinally adjusted projection of the finger from beneath its top, a bearing plate engaging the top of the arm and adjustable along the arm as the finger, said arm top being provided with a longitudinal slot therethrough, a wristpin journalled in the other nger end, a control member threadedly engaging the wristpin transversely of its rotative axis and extending through said slot and operative in tension between the wristpin and the bearing plate, and means independently cooperative between the control member and arm for longitudinally adjusting the member to rock the finger between operative and inoperative positions thereof.

6. A structure in accordance with claim 5 whereof the adjusting means for the control member comprises a cam lever directly operative against the bearing plate and pivotally carried by the control member.

7. In a device for clampedly holding a workpiece against a bed-plate, a clamping finger providing a forward work-engaging end and intermediately mounting a fulcrum pin in laterally extended fixed relation thereto, an arm xedly related to the bed-plate in spaced opposed relation thereto and providing a longitudinal guideway beneath a top portion of the arm and fittedly receiving the ends of the fulcrum pin of the finger for a longitudinal adjustment of the finger with respect to the arm and beneath its top portion, a bearing plate frictionally engaging the upper face of the arm top and adjustable along the arm opposite an elongated opening provided through its top longitudinally thereof, a control member extending through said arm opening and operative in tension between the bearing plate and the rear end of the finger to clampedly engage the work-engaging end of the finger with a work-piece disposed between it and the bedplate, and a spring means constantly and yieldingly operative between the rearward finger portion and the arm top for resisting an operative action of the control means and maintaining a frictional engagement of the bearing plate with the top face of the arm to provide for a set longitudinal adjustment of the plate and nger while the nger is inoperative with respect to a workpiece.

LOWELL L. PRICER..

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

UNITED STATES PATENTS