US2178264A

US2178264A - Work holder with layout and checking device

Info

Publication number: US2178264A
Application number: US198892A
Authority: US
Inventors: Adolf L Meyer
Original assignee: Individual
Current assignee: Individual
Priority date: 1938-03-30
Filing date: 1938-03-30
Publication date: 1939-10-31
Anticipated expiration: 1956-10-31

Description

Oct. 31, 1939. M YER 2,178,264

WORK HOLDER WITH LAYOUT AND CHECKING DEVICE Filed March so, 1938 4 Sheets -Sheet 1 INVENTOR, IqDOLF L-NEYER ATTORNEY v 0d. 31, 1939. v ALQMEY ER 2.118.264

/ WORK HOLDER WITH LAYOUT AND CHECKING DEVICE Filed March so, 1958 {r Sheets-'Sheet 2 3.rg.3.

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T T m' 6 I] 2 I l 45 44 l 5 /fi -23 f I I 5/ I f l I 3 0 6.5 29 46 INVENTOR.

14 28 By 400m L. MEYER /6 7 78 Non/ aw,

' k7 ATTORNEY Oct. 31, 1939. A. L. MEY R v 2.178.264

WORK HOLDER WITH LAYOUT AND CHECKING DEVICE Filed llarch 30, 1938 4 Sheets-Sheet 3 ATTORNEY.

Oct. 31,1939.

A. L. MEYER 2.178.264

WORK HOLDER WITH LAYOUT AND CHECKING DEVICE Filed March so, 1938 4 Sheets-Shet 4 INVENTOR. 'KlaoLF L. MEYE BY Ji 24-90%) A TTORNEY Patented a. 31, 1939 UNlTED srA'ras PATE To F c WORK HOLDER WITH I LAYOUT AND CHECK- ING DEVICE Adolf L. MeyerrBerkeley C lif. Application March 30,1938, Serial No. 198,892

6 Claims. (01. 33-114) The invention relates to a work holder arranged for layout and checking operations on work pieces such as stampings from sheet material.

An object of the invention is to provide for laying out and/or checking the lines and points of a work piece from the dimensions on the drawings thereof and while the piece is fixedly mounted on an adjustably mounted head of the apparatus.

Another object is to provide an improved gaug-.

ing method wherein all measurements are set or taken in accordance with adjustments of the head which are measurable on appropriate scales unitarily associated with it.

A further object is to provide an improved gauging device of the character described wherein all correct straight lines of a mounted piece are arranged to bedisposed in the same reference plane for their gauging, and said reference plane may be readily established and re-established without requiring a dismounting of the piece.

An added object is to provide for working on the piece while it is mounted on the head.

The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set forth or be apparent in the Figure 6 is a fragmentary section at as in Figure 4.

Figure .7 is a section taken at 7-7 in Figure s. Figure 8 is a section taken at the broken line 88 in Figure 7 Figures 9 to 12 inclusive are somewhat diagrammatic face views showing the work piece in various testingpos'itions on the unit.

Essentially, the apparatus for accomplishing the present objects comprises a surface plate on which a work-holding head is adjustably mounted for its rotativ'e adjustment about an axis having a predetermined angular relation to the reference face of the surface plate, and for its translation toward and from the surface plate independently'of its rotary adjustment. Suitable scales are provided for gauging the rotary and translatory adjustments of the head which is provided with means for effecting the fixed and adjusted mounting of a work piece upon it. The

apparatus utilizes a suitable surface gauge which is freely movable over the face of the surface plate with the gauging arm having its point set and'maintained at a flxed distance from the surface plate whereby it is operative in a fixed reference plane to which all point and straight-line measurements of the mounted workpiece are re ferred by measured adjustments of the head, the method of use of the apparatus having certain, marked advantages which are hereinafter brought out. 15

In the disclosed form of the apparatus for carrying out the present invention, a work-holding head i4 is supported from a base plate i5 which has a top face portion l6 thereof accurately machined and ground or scraped as a surface plate. A standard I! extends fixedly from one edge of the plate l5 and slidably carries a head-block element l8 which mounts the head M for solely rotary adjustments thereof, and complementarily engages the standard for its guided movement in a line which is perpendicular to the face it. In the present instance, one side of the standard provides mutually spaced and parallel tracks is of trapezoidal cross-section which are ,slidably and closely engaged. with opposite side portions of a complementary slot of the block it in the manner of a dove-tail to positively and accurately guide the element in its permitted range of adjustment with respect to the face it of the surface plate i5.

. A tongue portion N of the head-block 88 extends freely into the space between the tracks i9 and threadedly receives a screw 22 which is swivelled in the standard ii for its rotation to adjust the head-block while supporting the latter in its place, the axis of the screw being perpendicular to the face I6 of the plate Hi. In the present instance, the screw 22 is swivelled in a head member 23 of the standard whereby the head block I 8 is adjustably supported in its place by $5 the screw. An upwardly protruding screw portion carries a suitable means for use in turning the screw to'eflect adjustments of the head block; a hand crank 24 is particularly shown for the purpose.

Means are provided for accurately ascertaining the amount of movement of the head block from an initial setting thereof, said means being provided as part of the standard and screw assembly. As particular] y shown, a member 25, which 23, is conically tapered above the latter and registers with the lower end of a tubular having the scale on defines the top of the swivelling socket for the screw and is fixed in the standard top member member member 26 mounted on the extending screw portion below the crank 24, and the mutually adjacent parts of the exposed side faces of the

members

25 and 26 are graduated in such a manner that the differences between readings for successive settings will directly give the distance moved by the block between said settings. The present tool is a precision tool, and'readings of the required degree of accuracy would be provided for, as by utilizing a screw of relatively low pitch and one of the

members

25 or 25 comprise a vernier scale for use in a well-known manner.

It will now be noted that the present head I4 is disc-shaped and is fixed on a spindle 21 which extends perpendicularly to the outer face 28 of the head and is arranged to Support the head for its rotation about the spindle axis. Means are provided on the head for mounting a piece of work thereon in adjusted position opposite the face 28; as particularly illustrated, the head I4 i provided with a series of T-slots 29 opening from the face 28 and arranged to receive the heads of usual clamping'screws 3|, the screws carrying nuts 32 which may'directly engage the article to be gauged, or a carrier for the article, to fix the work on the head. Preferably, and as shown, the slots 29 radiate from the head axis and aligned pairs thereof are mutually perpendicular, the specific arrangement facilitating an adjusted mounting of the work piece on the head.

The head-carrying spindle 21 extends axially through and is journalled in a tubular casing member 33, said member being mounted on the block l8 in fixed relation thereto and having one end finished to provide an annular face 34 which is perpendicular to the spindle axis for its flat engagement with the finished rear face 35 of the head, which latter face is also perpendicular to the spindle axis. The bearings provided for the spindle are arranged to maintain the same axially centered in the casing while permitting the necessary slight axial movement of the head to and from a forcible and frictional engagement with the casing end face 34, said engagement being utilized to fix the head in rotatively adjusted relation to the casing. The spindle and head may be provided with an axial bore for the operation longitudinally therethrough of a usual knock-out bar (not shown) as an aid in dismounting work from the head.

As illustrated, a centrally perforated cross-wall 36 is provided at the rear end of the casing 33, and is recessed from its rearward face for the fitted reception of the outer race ring of a ringbearing assembly 31 which provides the rear bearing for the spindle. The bore of the casing 33 is stepped inwardly from its forward end to provide for a limited degree of insertion within the casing bore of the outer race ring of a ringbearing assembly 38 which provides the front spindle bearing. A flange 39 is threadedly mounted on the rear spindle portion and is fixed against a shoulder 4| at the forward end of the threaded spindle portion which mounts it by means of a lock-nut 42. The flange 39 spans the bearing 31 and has its outer portion disposed opposite the wall 36 for contact with the wall only. when the head 14 is moved forwardly out of frictional contact with the casing face 34; in this manner, the mounted spindle is retained in the casing while the mutually opposed casing and head faces 34 and 35 are either engaged or disengaged.

A hand-wheel nut 43 is threadedly mounted on the extreme inner end of the spindle 21 and is hollowed out from its forward face to span the flange member 39 and engage only the rear wall 36 of the casing, the opposed nut and wall faces being finished. A turning up of the nut 43 on the spindle to engage it with the wall 36 is arranged to effect a forcible engagement of the head l4 against relative rotation with respect to the casing, and so lock the head in rotatively adjusted position on the casing. A subsequent backing off of the nut 43 will release the head for its rotative adjustment, the required amount of turning of the nut for releasing the clamped head being obviously slight.

An arcuate scale plate 44 is fixed on the casing 33 to extend radially beyond the periphery of the circular head l4, and carries vernier graduations 45 extending from a central zero point and for use with angle graduations 46 extending on and around the peripheral edge of the head whereby to provide for predetermined rotary adjustments of the head about its axis or to ascertain angular relations of a work piece. To facilitate angle readings and settings, the zero of the graduations 45 may be provided at a point which lies in a plane which includes the spindle axis and is perpendicular to the reference face I6 of the surface plate I5. Also, the zero of the angle scale on the head is preferably provided at a point which lies in a plane including the spindle axis and the longitudinal center line of a T- slot 29.

-Means are preferably provided for effecting a controlled rotative adjustment of the head l4 about its axis for angle-setting purposes, said means essentially comprising a gear drive which is optionally operative against the spindle 21. As shown, a shaft 41 is journalled in the casing 33 intermediately of its length and to extend perpendicularly of the spindle axis in non-intersecting relation to said axis. The shaft 41 carries a worm gear 48 fixed operative in the casing cavity and in a tangential direction against the teeth of a complementary spur gear 49 which is mounted on the spindleifl for its normally free rotation about the spindle, the gear 49 being disposed adjacent a rearwardly extending shoulder of the spindle adjacent the forward end of the casing cavity. One end of the shaft 41 extends externally from the casing and carries means for manually effecting its rotation, the latter means being shown as comprising a hand crank 5i.

A clutch means is provided for causing the gear 49 to rotate with the spindle whereby an actuation of the hand crank 5| may controlledly rotate the spindle and head as desired. As particularly shown, a sleeve member 52 is mounted on the spindle between the gear 49 and the rear casing wall 36, and is splined to the spindle for its rotation therewith and its adjustment .along it. A socket 53 is provided in the rear face of the gear 49 for receiving a pin 54 which extends forwardly from the sleeve 52 at the same radial distance from the spindle axis, and an helical compression spring 55 is constantly operative between the rear sleeves end and the wall 36 to urge the sleeve toward the gear to engage and yieldingly maintain the pin in the socket so that the manually rotated gear may rotate the spindle and head when the pin engages the socket.

Since the rotary adjustment for the head by means of the worm gearing is relatively slow, the described clutch arrangement is normallyheld inoperative by a screw 56 threadedly engaged in and through the side wall of the casing 33 and releasably engaging the sleeve in a manner to dispose the pin 54 rearwardly of the socket '63. As shown, the inner end of the screw 56 -is conically tapered and is arranged for its wedging engagement with the forward side of a complementary conical flange 51 provided on the sleeve and having its apex forwardly. As the screw 56 is turned in, it is arranged to force the sleeve rearwardly against the resistance of the spring- 55 to disengage the pin 54 from the socket 53 and so render the .worm gearing ineffective as an adjusting means for the head; when the head, having been freed for its rotary adjustment by loosening'the hand nut 43, is set approximately, the clutch control screw 56 is backed out of its engagement with the flange 51 to permit the clutch engagement, and the crank may then be operated to complete the with precision. The head of preferably knurled or otherwise formed to facilitate a manual manipulation of the screw.

It will now be noted that the head block 18 comprises an inner portion 58 providing the tongue l8 engaged by the 'screw 22 and the groove which receives the tracks 19, a bracket-arm portion 59 extending from the portion 58 at the lower part thereof, and an upstanding ear 6| at the end of the arm 59. The oposed faces of the' portions 58 and SI are mutually parallel in planes perpendicular to the surface plate face l6, and a bolt 62'extends through the ear 6i and the headcarrying casing 33 into the block portion 58as a means to mount the casing on the bracket provided by the block, the axis ofsaid bolt being parallel to the front head face l6.

Mutually aligned bosses 63 provide the end portions of the head-receivlng bore of the casing 33, the end faces of the bosses being mutually parallel and so spaced as to provide for their simultaneous fitted engagement against the opposed faces of the block portions 58 and Si when the bolt 62 is installed. The bolt-receivthe screw 56 is ing bores of the ear SI and of the casing 33 are smooth, and the bolt portion thereat may be unthreaded for its snug centering fit therein. The inner bolt end is threaded and engages a threaded bore in the block portion 58 whereby a tightening of the bolt against the ear 6! may clamp the boss portion of the casing 33 between the portions 58 and ti to frictionally secure the casing against rotation about the bolt axis; this arrangement permits a rotativelyset adjustment of the working head It with respect to the plane of the surface plate l5.

Arms 66 are fixedly mounted on the casing 33 at opposite sides thereof and extend laterally thereof beyond the head il and into the general plane of the head disc. At its outer end, each arm 56 has a relatively small transversely directed projection 65 having its free end face 68 coplanar with the axis of the head it and providing a reference face which is arranged to be parallel to the gauging face it of the surface plate when the head axis is parallel to the latter face. The reference faces 86 of the difierent arms 66 are oppositely directed,'mlght be provided on the same supporting arm, and are provided-for use -with a surface gauge supported on the face iii in certain gauging operations hereinafter described.

angular setting The surface'gauge which is provided and utilized for the present purposes may be of any suitable type or structure for engaging the work asrequired while providing the desired degree of gauging accuracy. The illustrated surface gauge 61 is of the dial indicator type wherein the indicator 68 is adjustably mounted on a stem 69 which extends from a base 1| arranged for supported movement on and along the top face 16 of the surface plate i5. An arm .12 extends from the indicator for the engagement of its free point 13 with either reference face 66 and with correspondingly directed points and surfaces to be checked for determining indicator readings.

The gauging of an article or work piece 15 is particularly shown for illustrating the method of use of the present apparatus, said article comprising a machine partwhich is shaped .and

stamped from sheet material and being flat except for a flat lug part 16 which extends transversely from the rest of the'piece, and presents a flat stop face 16'. A circular hole 11 which extends transversely through the piece 15 is utilized inmounting the piece 15 on the head 14 by driving a slightly tapered pin 18 into the hole 11 to mount the piece on the pin, fixing the pin in a V-block clamp 19, and mounting the clamp on the head with the pin perpendicular to the head face 28 by the use of one or more screws 3|; as shown,- but one clamp screw is utilized to'secure the present work holding clamp 19. It will be understood that the hole 11 may be arequired one in the piece, or may be one which is provided especially for mounting the piece in a work holder of the type shown.

It will now be noted that the piece 15 has several formal features and dimensions which must be adhered to with precision in the'flnished manufactured article. For instance, the piece is provided with an interior pin-guiding slot of uni form width having a straight portion Bland an arcuate portion 82 in definite relation to the axis of the hole 11, and the lug 16 has a definite position in the piece, all as exemplified in Figure 2' which presents the draftmans drawing for the of present interest shown.

By reference to Figure 2, itwill be noted that all of thegiven dimensions are measured from perpendicularly related reference lines :r-a: and 11-11, which lines intersect at the center C for the. hole 11, and that slot portion 86 are parallel .to. the line .r .r at distances a and b from it. The end lines of the slot Sl-BZ are semicircles having their radii r equal to half of the slot width and having their centers at measured mstances from the lines :c :r and 11-11; the'arc at the end of the slot nearest the point C is a distance 0 from the line :r:c and a distance d from the line 11y, while the center for the other slot end is a distance 6 from the line :c-.r and a distance I from he line y-1 The center of curvature P for the curved sides of the arcuate slot portion 82 lies at the distance d from the line z/y and at a distance 9 from the line 2-1:; accordingly, the radius of curvature for the arcuateslot side nearest the center P equals the distance 9 minus r (gr), while the radius of the opposite slot side equals g plus r (g+r). In the present piece 15, the stop face 16' of the outturned lug 16 is arranged to be pendicular to the rest of the piece and to include the axis of the hole 11 in its plane and to make a definite angle A with the reference line 31-11,

as shown, the center for of the clamp the sides of the straight 4- a blank being suitably marked as at m to indicate the proper inside bend line for the lug. The outlines of the piece are also delineated in Figure 2, the dimensions and measurements thereof being omitted in the present instance for simplifying the showing.

As is particularly'illustrated in Figures 1, 3, 4, 9, 10 and 11, the piece 15 is shown as being so positioned on the head that the axis of the hole 11 coincides with the spindle axis. This mounted disposal of the piece may be readily eflected by setting the head 14. at a convenient and fixed height with its axis parallel to the top face 16 of the surface plate l5 and with the slot 29 which receives the clamp screw 31 vertical for a zero reading on the head scale. Since the only requirement for the initial height setting of the head is that subsequent height adjustments required for gauging be permitted, the head may be conveniently disposed for a whole number reading on the height scale. The point 13 of the surface gauge 61 may then be applied to the top or bottom side of the pin 18 for setting the point height, the head I4 is then rotated through an angle of ninety degrees, and the set point 13 is again and similarly applied to the pin; if the indicator readings are the same (preferably zero) for both applications of the point 13 to the pin 18, the latter is properly centered, otherwise, an

adjustment of the work-mounting member 19 is made until said readings are equal.

When the mounting pin 18 has been centered as described, the point 13 of the surface gauge 61 is set for its movement in a reference plane at the distance of the spindle axis from the surface l5 by adjusting it for a zero reading of the indicator when it engages the upwardly directed reference point 66. The head is then lowered the distance a, the pin 18 is loosened for its centered rotation in the member 19, and the piece 15 thereon is rotated about the head axis to a position wherein the straight slot edge portion to whichthe measurement 11 applies is disposed for the application of the set gauge point 13 to it from above and for a uniform reading of the indicator as the point 13 is moved along its length, whereby the slot edge may be parallel to the reference plane in which the set point 13 is movable. If the indicator reading is the same as when the gauge point was originally set, the tested edge is also correctly spaced from the axis a:--.'r. The aforesaid completed setting of the piece with respect to the head is thereafter maintained by tightening the grip of the work holder on the pin 18 and is that specifically shown in Figure 9. It will be understood that other straight edges of the piece may be similarly tested with the gauge point 13 having been initially set against a correspondingly directed reference face 68 when the piece was at its initial level.

For checking the distances of the ends of the ends of the slot 81-82 from the line y-y, the head H is rotated through ninety degrees from its Figure 9 position to correspondingly rotate the work piece, the head angle scale 46 being utilized for measuring the angle. As shown in Figure 10, the set gauge point 13 is applied for checking the distance of the end of the slot nearest the pin 18 from the pin, and the head has accordingly been lowered a distance of (1 minus 1' (d-r) whereby the point to be checked presumably lies in the reference plane of the point 13 and will be correct only if the indicator reading is zero as when the point was originally set at the reference point 63.. The other slot end may be similarly checked tight in this setting.

by turning the piece downwardly instead of upwardly, the head being lowered a distance of j plus r (f+1'). It will be understood that other points of the work piece may be similarly checked with respect to either of the lines :c-a: or 11-41. 5 The angular relation of straight lines of the tested piece to other lines of the piece or to the lines z-a: or y-y may be tested by comparing readings on the head scale when the different lines at interest are disposed in the common ref- 10 erence plane of the gauge point 13. As is shown in Figure 11, the head has been rotated in a clockwise direction from its initial position of Figure 9 through an angle of ninety degrees plus the angle A (90+A) to presumably bring the 15 lug face 16 into the reference plane. Checking is effected in this instance by applying the point 13 both along and across the face 16', whereby to ascertain as to whether the'face is truly perpendicular to the plane of the rest of the piece 29 and includes the pin axis, provided the angle is correct.

Figure 12 shows the piece disposed on the head for using the gauge point 13 for checking the accuracy of the arcuately curved inner edge of the 5 slot 8l--82. For performing this operation, the piece is reset on the head so as to bring the center P into the axial line of the head I4, the pin 18 being shifted away from said center by the direct distance from B to C, which distance is readily so determined by measurement or computation in the original scale drawing. With the head It lowered for the distance g minus 1 (9-4) and the pin 18 loosened for its rotation, the piece is swung about the pin to dispose the gauge point 13 35 against the slot edge being tested and is clamped I A subsequent rocking of the head about its axis to move the curved edge beneath the point 13 will provide thedesired test for the correctness of curvature. This setting is 4.0 understood to provide for checking all arcs having P as the center. Also, it will be noted that the circular edge portion centering about the pin 18 may be tested for accuracy of curvature when the piece is mounted as in Figures 9 to 11 sim- 4,5 ply by rocking said edge portion beneath and in contact with the gauge point 13.

It will be noted that the foregoing applications of the present apparatus for testing and checking are illustrative of but a few of the operations 50 which may be devised and performed by a mechanic. Also, the piece being tested may be a pattern, a partly finished article, or a completed article. If the surface gauge used provides a scribing point, a scribed outline may be checked 55 or produced on a blank if desired, all solely by' the described use of the head scale and the elevator scale and the reference point 66 in mutual cooperation. Furthermore, the described provision and measuring use of the relatively large 00 head and elevator scales in lieu of the relatively small scales of a surface gauge are understood to provide a degree of checking precision not obtainable with the gauge scale.

While the indicated use of the reference point 55 65 to establish a reference plane for gauging operations is generally feasible only when the spindle axis is parallel to the surfaceplate face 16, the permitted angular adjustment of the head assembly about the axis of the bolt 62 may pro- 70 vide for the disposition of bevelled faces for their testing with the surface gauge in the described manner.

If desired, a rotary power tool 85 may be mounted on the base plate 15 for the application of a drill or reamer or grinder or other rotary tool to a work piece mounted on the head 14, this being of marked value since it permits correctzing a pattern, or a presumably finished piece, 5 without having to release it from the head for tool unit is preferably held against lateral shifting over the plate face l6; as by dowel pins extending downwardly from the base of the assembly 81 and into sockets 88 provided in the plate I5.

From the foregoing description taken in connection with the accompanying drawings, the ad- 'vantages of the construction and method of operation will be readily understood by those skilled in the art to which theinvention appertains. While I have now described the features and prin- 3 ciples of operation of a structure which I now consider to be a preferred embodiment of my invention, I desire to have it understood that the showing is primarily illustrative, and that such changes may be made, as desired, as fall within the scope, of the following claims.-

1. A work holding and checking device comprising a base providing an upwardly facing and plane reference surface, a'head block mounted on said base for rectilinear adjustment with respect to said base surface, a Work holding head mounted on said block for rotary adjustment with re spect to an axis parallel to said reference surface,

and means providing a reference point on the.

block, said point comprising a flat area parallel to said base surface for reference engagement by the gauging point of a surface gauge standing on. the base surface.

2. A work holding and checking device comprising a base providing an upwardly facing and plane reference surface, a head block mounted on the said base for rectilinear adjustment with re spectto said base surface, a work holding head mounted on said block forv rotary adjustment with respect to an axis parallel to said' reference surface, and means providing reference points on the b ock, said points comprising mutually coplanar fiat areas parallel to said base surface for reference engagement by the gauging point of a surface gauge standing on the base surface.

3. A work holding and checking device com: prising a base providing an upwardly facing and plane reference surface, ahead block mounted on the said base for rectilinear adjustment with respect to said base surface, a work holding head mounted on said block for rotary adjustment with respect to an axis parallel to said reference surface, and means providing a reference point disposed on the block adjacent the periphery of said work holding head, said point beingarranged for reference engagement by the gauging point of a surface gauge standing on the base surface.

4. A work holding and checking device comprising a base providing an upwardly facing and plane reference surface, a head block mounted on said base for rectilinear adjustment with respect to said base surface, a work holding head mounted on said block for rotary adjustment with respect to an axis parallel to said reference surface, and means providing a reference point on the block disposed in a plane including the axis of rotation of the head and parallel to the reference surface of the base, said point being arrangedfor reference engagement by the gauging point of a surface gauge standing on the base surface.

5. A work holding and checking device comprising a base providing an upwardly facing and plane reference surface, a head block mounted on the said base for rectilinear. adjustment with respect to said' base surface, a work holding head mounted on said block for rotary adjustment with respect to an axis parallel to said reference sur-.

face, and means providing a reference point on the block laterally of the head, said reference point being disposed in a plane including the axis of rotation of the head and parallel to the ref- .erence surface of the base and being arranged for reference engagement by the gaugingpoint of a surface gauge standing on the base surface.

6. A work holding and checking device comprising a base providing an upwardly facing and plan-e reference surface, a head block mounted on said base for rectilinear adjustment with respect to said base surface, a work holding head mounted on said block for rotary adjustment with respect to an axis parallel to said reference surface, and oppositely directed reference faces'provided on the block, said faces being arranged for reference engagement by the gauging p bint of a surface gauge standing on the base surface.

ADOLF L. mm.