US2474800A

US2474800A - Magnetic fixture for holding work to be ground

Info

Publication number: US2474800A
Application number: US642328A
Authority: US
Inventors: Richard G Nill
Original assignee: Fort Wayne Tool
Current assignee: Engineering Co
Priority date: 1946-01-19
Filing date: 1946-01-19
Publication date: 1949-06-28
Anticipated expiration: 1966-06-28

Description

R. G. NlLL June 28, 1949.

MAGNETIC FIXTURE FOR HOLDING WORK TO BE GROUND Filed Jan. 19, 1946 2 Sheets-Sheet 1 IN V EN TOR.

5 F A m m .m m J wm .m E rlllallllllL W 7 1 /1 m June 28, 1949.

MAGNETIC FIXTURE FOR HOLDING WORK TO BE GROUND Filed Jan. 19, 1946 R. G. NlLL 2,474,800

2 Sheets-Sheet 2 Patented June 28, 1949 MAGNETIC FIXTURE FOR HOLDING WORK TO BE GROUND Richard G. Nill, Fort Wayne, Ind., assignor to Fort Wayne Tool, Die and Engineering Company, Fort Wayne, Ind., a partnership Application January 19, 1946, Serial No. 642,328

10 Claims. 1

This invention pertains to a fixture for hold ing work to be ground, and more particularly to a fixture for holding work, one edge of which is to be finished and shaped, or a fixture adapted for holding work to be straight ground.

It is an object of this invention to provide a fixture for positively holding work to be ground in such a manner that no scarring of the work can happen.

Another object of the invention is to provide a fixture for holding work to be operated upon, in a plurality of directions whereby the operating tool cannot move said Work.

Another object of the invention is to provide a fixture for holding work to be operated upon in such a manner that a plurality of mating segments of the work can be operated upon at once and in a similar manner.

Another object of the invention is to provide a fixture for holding work to be operated upon whereby a shape such as back taper can be readily ground on a plurality of work members.

With these and various other objects in view, the invention may consist of certain novel features of construction and operation as will be ,more fully described and particularly pointed out in the specification, drawings and claims appended hereto.

In the drawings which illustrate embodiments of the device and wherein like reference char act-ers are used to designate like parts- Figure l is a fragmentary elevation of a fixture embodying the invention, shown particularly for holding a plurality of segments, the ends of which are to be ground;

Figure 2 is a top plan view of the fixture illus trated in Figure 1;

Figure 3 is an end elevation of the fixture illustrated in Figures 1 and 2;

Figure 4 is a top plan view of a pair of segments illustrating the grinding of back taper thereon;

Figure 5 is an elevation looking toward the ground end of the segments illustrated in Figure 4 showing the grinding of the back taper thereon;

Figure 6 is a top plan view of a modified form of fixture adapted particularly for grinding lamination punches;

Figure 7 is an end trated in Figure 6;

Figure 8 is a fragmentary end elevation of the fixture illustrated in Figures 6 and '7 showing the same with the end gauge bar removed; and,

Figure 9 is an end elevation, partly in section, of a modified form of fixture shown in Figures 6 to 8 inclusive.

elevation of the fixture illus- Referring first of all, more particularly, to the fixture illustrated in Figures 1 to 3 inclusive, said fixture comprises the base 29 provided with securing means or member 22 for facilitating the securing of the fixture assembly in position with respect to an operating tool for the work held by the fixture, for example, a grinder. The base is provided with the Work holder base it and with a magnetic power unit 26. The base 2b is secured as at 28 to the securing means 22 and the power unit is secured thereto as at 3G to the securing means 22 and as at 32 to one portion of the work holder base 2d.

The work holder base 2d comprises two parts or blocks t l and 36 of magnetic material such as steel, said parts being bonded but insulated from each other by means of the brazed joint 38 of non-magnetic material, such as brass. The work holder base is secured as at it] to the base 29, and the work holder 42 is secured as at a l and ts to the work holder base 2 5, the securing means 45 also serving to secure in place the top gauge bars 48 of the adjacent work holding members 42.

The work holding members 42 comprise a pair of

work holding blocks

50 and 52 of magnetic material such as steel, secured together but insulated by means of the brazed, non-magnetic joint 54, preferably of brass. The joints li t and 38 are aligned and the joint M is preferably so disposed that it is slightly overlapped by means of the top gauge bar 48. The adjacent work holding blocks 58 and 52 (and consequently adjacent bars d8) are preferably angularly disposed with respect to each other (Figure 1) so that when work with open edges is ground a desired back taper will be ground on the said work. The work contacting surfaces 55 of the adjacent blocks 5!] are also sloped one with respect to the other (Figures 2 and 3) so that a proper back taper is ground on the edges of the work held on the fixture.

End gauge bars 58 are disposed adjacent one side of each of the members 42 for engaging the ends of the work 50 held on the members 42 whereby they can be properly positioned. When the segmentsor Work Ell are to ice finished, as by grinding, each segment is disposed so that the two rear edges, that is, the edge not to be ground, contact the edge of the adjacent gauge bar 48 (Figure 3) and one end of the said segments engages the adjacent end gauge bar 58 (Figure 2).

The power unit 26 is energized and magnetic fiux passes from the power unit through memthe work-holder-is ber 36, block 52, gauge bar 48, work 60, block 50, member 34, base 20, member 22, back to the power unit, all as shown by the arrows. Thus the work, that is, segment 60, is held both against the surface 56 and against the edge of the gauge bar 48. The segments are placed on the adjacent work holding members 42 with the tops of the segments adjacent to each other, as illustrated in Figure 4. The grinding tool can then be operated over the work properly grinding the open edge of the work and at the same time forming the open edge of the segment with the proper back taper, removing the metal as indicated by the dotted lines as at 62 in Figure '4, and removing metal along the 'free 'edge as shown by the dotted lines 64 in Figure 5. The segments can be reversed maintaining the tops together for grinding the opposite side of the edges thereof, It is, of course, understood that while only two adjacent work holding members 02 are shown, any number otsets (pairs) of these work holding members may be used on the fixture. 7

Referring now to the fixtures illustrated in Figures 6 to 8inclusive, said fixtures comprise [the base plate 66 provided'with securing means 68 for .conveniently fastening the fixture to a machine, such as a grinder. The base plate is provided with the work holder 10 having securing means 12, theen'd of the work holder I being provided'withthe end gauge bar "I0 secured thereto as'at 76. Both ends may be provided with said gauge bars, if desired. The work holder I0 is formed-ofspac'ed blocks 18 and 80 "of magnetic material suchas steel connected together by the brazed joint 82 of non-magnetic material, such as brass. I The base plate 66 is connected to the work holder 70 by means of the steel plate 84 (and securing means 12), and a power unit 86 is interposed between'the base plate'fifi and'the block 80 of work holder 10. 'The work holding block 80 is provided with the top gauge bar 88, secured thereto as at 90, and is preferably of magnetic material such as steel. The fixture illustrated is adapted particula'rly'forgrinding punches, and blocks 80 and I8 arefo rm'ed with the punch-seg- -ment receivingrecess 92fSO shaped that the top of segment 94is presented properly to'the grinding wheel.

The punch segment 91 is disposed in the recess and overlies thebrazed, non-magnetic joint-82 (Figure 8),-one edge 95 of-the punch abutting the adjacent edge -91 of-the top gauge bar 88. When the power unit 86 is-energized, magnetic *flux will flow 'from'said unitthrough the block '80,through gauge bar 88,-through work'9 l, block 18, plate 84, base plate' 66,: and to'the'power unit -86, whereby the-segment 94 is'held in a downward "direction against blocks "I8 and 80. It is,

*of course, understood 'that'these'gments maybe positioned longitudinally of the fixture by abut- :"ting the endgauge bar 14.

In'Figure 9 is shown'a fixture having a base 96 corresponding to'bas'e 6B, the-base being provided with a support- 98, corresponding to support 84 interposed betweenthe base, and the work holder I00, corresponding to work holder 10. As before, Fthe "workhold'er "shown is r for a punch segment where only a straight out or "straight grinding operation is performed, and properly-shaped to'present the work to the grinding wheel in the manner desired. 'Apower unit 10 2 is interposed between the base- 06 and the wo r'k holder I00. It 'is unsupport 98 and through base 96 power unit, as shown by the arrows whereby the of-the work holder'base blocks, holderblocks, 'top'gaugebar, work, the other of ported by said support derstood that an end gauge bar (not shown) or gauge bars, similar to gauge bar 14, may be used and a top gauge bar I04 is secured to the Work holding block I06 of the work holder I00. Block I06 is separated from block I08 of the work holder by the brazed, non-magnetic joint IIO, preferably of-brass, and as before, members 96, I 06 are of magnetic material, such as steel,

In this modification the gauge bar is so disposed that it-slight'ly overlaps the non-magnetic joint lflfl and the edge of the gauge bar abuts and positions the work I I2 by engagement with v an edge thereof. When the work H2 is support- 'ed, one edge thereof slightly overlaps the brazed joint and when the power unit is energized, magnetic flux passes from the power unit I02, through block I06, gauge bar I04, work I I2, block I08, back to the Work is held both downwardly-and edgewise, thus preventing any tendency of operating tool, such as the grinding Wheel, from laterally moving the work.

It is to 'be understood that this application is not to be limited by the exact embodiments of the device shown, which are merely by way of illustration and not limitation as various and other forms of the device will, of course, be apparent to those skilled in the art without departing from the spirit of the'inventionor the sco'pe'of the claims.

.I claim:

1. In a fixture, the combination of a base of magnetic material, a support of magnetic material disposed on said base, a work holder base disposed on said support, said work holder base and support being adapted to bemagnetically connected to a magnetic power unit, said work holder base comprising a plurality of blocks of magnetic material.separatedibut joined by nonmagnetic material, one of said'blocks being magnetically connected to said power unit and the other being magnetically connected to said support, a work holder supported on said work holder metallic wo'rk so'disposed on'the 'work holder block whichis spacedfromthe' top gauge bar and overlying "the 'nommagnetic' material to engage said top'gaugebar wherebywh'en said power unit is energized'magneticflux passesthrough one one'of the-work the work holder blocks, the otherof the work holder baseblocks, the support; and the base, back to the power unit to magnetically fixedly secure said work to said fixture.

2. "In afiz'zture, the com'bination of a base'of magnetic mater-ial,--a--support ofmagnetic material dispose'd'on said'b'a-se,-'a 'Work'holder supand comprising spaced blocks of magnetic material, said-workhol'der base and support being adapted to be magnetically connected to a magnetic power unit, one of said blocks being magnetically connected to said power unit, and the other of said blocks being magnetically connected to said support, the blocks of said work holder being separated but connected by non-magnetic material and a top gauge bar of magnetic material secured to one of the work holder blocks and having an edge overlapping the non-magnetic material but spaced from the other work holder block, said work holder being adapted to receive metallic work so disposed on the work holder block which is spaced from the top gauge bar and overlying the non-magnetic material to engage said top gauge bar whereby when said power unit is energized, magnetic flux passes through said power unit, work holder blocks, top gauge bar, work and support to fixedly secure said work to said fixture.

3. In a fixture, the combination of a base of magnetic material, a support of magnetic material disposed on said base, a work holder base disposed on said support, said work holder base and support being adapted to be magnetically connected to a magnetic power unit, said work holder base comprising a plurality of blocks of magnetic material separated but joined by non-magnetic material, one of said blocks being magnetically connected to said power unit and the other being magnetically connected to said support, a work holder supported on said work holder base and comprising spaced blocks of magnetic material, one of said blocks being magnetically connected to one of said first named blocks and the other of said blocks being magnetically connected to the other of said first named blocks, the blocks of said work holder being separated but connected by non-magnetic material aligned with and contacting the other non-magnetic material, and a top gauge bar of magnetic material secured to one of the work holder blocks and having an edge overlapping the non-magnetic material but spaced from the other work holder block, said work holder being adapted to receive metallic work so disposed on the work holder block which is spaced from the top gauge bar and overlying the non-magnetic material to engage said top gauge bar whereby when said power unit is energized, magnetic fiux passes through one or" the work holder base blocks, one of the work holder blocks, top gauge bar, work, the other of the work holder blocks, the other of the work holder base blocks, the support, and the base, back to the power unit to fixedly secure said work to said fixture.

4. In a fixture, the combination of a base of magnetic material, a support of magnetic material disposed on said base, a work holder supported by said support and comprising spaced blocks of magnetic material, said work holder base and support being adapted to be magnetically connected to a magnetic power unit, one of said blocks being magnetically connected to said power unit, and the other of said blocks being magnetically connected to said support, the blocks of said work holder being separated but connected by non-magnetic material, an end gauge bar on said work holder blocks, and a top gauge bar of magnetic material secured to one of the work holder blocks and having an edge overlapping the nonmagnetic material but spaced from the other work holder block, said work holder being adapted to receive metallic work so disposed on the work holder block which is spaced from the top gauge bar and overlying the non-magnetic material to Ill) engage said top gauge bar whereby when said power unit is energized, magnetic flux passes through said power unit, work holder blocks, top gauge bar, work and support to fixedly secure said work to said fixture.

5. In a fixture, the combination of a base of magnetic material, a support of magnetic material disposed on said base, a work holder base disposed on said support, said work holder base and support being adapted to be magnetically connected to a magnetic power unit, said work holder base comprising a plurality of blocks of magnetic material separated but joined by non-magnetic material, one of said blocks being magnetically connected to said power unit and the other being magnetically connected to said support, a pair of work holders supported on said Work holder base and disposed in predetermined relation to each other, each of said work holders comprising spaced blocks of magnetic material, one of said blocks being magnetically connected to one of said first named blocks and the other of said blocks being magnetically connected to the other of said first named blocks, the blocks of each of said work holders being separated but connected by non-magnetic material aligned with and contact ing the other non-magnetic material, an end gauge bar for each work holder, and a top gauge bar of magnetic material for each work holder secured to one of the work holder blocks of each holder and having an edge overlapping the nonmagnetic material but spaced from the other work holder block, said work holders being adapted to receive metallic work so disposed on the work holder block spaced from the top gauge bar and overlying the non-magnetic material to en gage said top gauge bar whereby when said power unit is energized, magnetic flux passes through said blocks, work, support and base, back to the power unit to fixedly secure said work to said fixture.

6. In a fixture, the combination of a base of magnetic material, a support of magnetic material disposed on said base, a work holder base disposed on said support, said work holder base and support being adapted to be magnetically connected to a magnetic power unit, said work holder base comprising a plurality of blocks of magnetic material separated but joined by nonmagnetic material, one of said blocks being magnetically connected to said power unit and the other being magnetically connected to said sup port, a pair of work holders supported on said work holder base and disposed in predetermined relation to each other, each of said work holders comprising spaced blocks of magnetic material, one of said blocks being magnetically connected to one of said first named blocks and the other of said blocks being magnetically connected to the other of said first named blocks, the blocks of each of said work holders being separated but connected by non-magnetic material aligned with and contacting the other non-magnetic material, and a top gauge bar of magnetic material for each work holder secured to one of the work holder blocks of each holder and having an edge overlapping the non-magnetic material but spaced from the other work holder block, said work holders being adapted to receive metallic work so disposed on the work holder block spaced from the top gauge bar and overlying the nonmagnetic material to engage said top gauge bar whereby when said power unit is energized, magnetic flux passes through said blocks, work, sup- ,7 port and baseback to'the powerunitxtofixedly secure said workto said fixture.

'7. In a fixture, the combin-ation of:a basero'f magnetic material, a support of magnetic material disposed on said base, a pair-of work :holders supported by said supportanddisposed in predetermined relation to each other, said support and work holders being adapted to be'magnetically connected-to a magnetic power unit, each of said work holders-comprising spacedblocks of magnetic material, one of said blocks being magnetically connected to one of said first named blocks and the other of said blocksbeing magnetically connected to the other of said first named blocks, the blocks .of each of said work holders beingseparated but connected by nonmagnetic material, an endgauge-bar for each work holder, and a top gaug-e bar of magnetic material for each work holder secured to one of the work holder blocks of eachholder and having an edge overlapping the non-magnetic material but spaced from the otherwork holder block, said Work holders being adapted to receive metallic work so disposed on the work holder block spaced from the top gauge bar andoverlyingthenonmagnetic materiahto engage said top gauge bar whereby when said powerunit is energized, magnetic flux passes throughsaid blocks, Work, support and base, backto the powerunit to fixedly secure said work to said fixture.

8. In a fixture, the combinationuof a base of magnetic material, a support of magnetic material disposed on said base, a pairof work holders supported by saidsupport and disposed in predetermined relation to each other, said support and work holdersbeing adapted to be magnetically connected to a magnetic power unit, each of said work holders comprising spaced blocks'of magnetic material, one of said blocks being magnetically connected to one of said first named blocks and the other of said blocks being mag- ,netically connected to the other of said first named blocks, the blocks of each of said work holders being separated but, connected by nonmagnetic material, and a topwgauge bar of magnetic material for each work holder secured to one of the work holder blocks of each holder and having an edge overlapping the non-magnetic material but spaced from the other work holder block, said work holders adapted to receive metallic work so being disposed on the work holder block spaced from the top gauge bar and overlying the non-magnetic material to engage said top gauge bar whereby when said power unit is energized, magnetic flux passes through said blocks, work, support and base, back to the power unit to fixedly secure said work to said fixture.

9. :In a fixture, .the combination of a base of .magnetic material, a support of magnetic mate- ;rial disposed on said base, a work holder supported by said support and comprising spaced blocks of magnetic material, said work holder base and support being adapted to be magnetically connected to a magnetic power unit, one of said blocks being magnetically connected to said power unit and the otherofsaid blocks being magnetically connected'to said support, the; blocks of said work holder being separated but connected by non-magnetic material and a top gauge bar secured to one of the work holder blocks and having a Work engaging edge spaced from the nonmagnetic material, saidwork holder being adapted to receive metallic work so disposed on the work holderblock which is spaced from thetop gauge bar and overlying the non-magnetic material to engage said top gauge bar whereby when said .power unit is energized, magnetic flux passes through said'blocks, work support, base, back to the powerrunit to fixedly secure said work to said fixture.

10. In a'fixture, the combination of a base'of magnetic material, asupport of magnetic material disposed on said base, a work holder supported by said support and comprising spaced blocks of magnetic material, said work holder base and support being adapted to bemagnetically connected vtoa magnetic power unit, one of said blocks being magnetically connected to said power unit, and the other of said blocks being magnetically connected to said support, the blocks of said work holder beingseparated but connected by nonmagnetic'material, an endgauge bar provided on said'blocks and atop gaugeibar secured to one of the work holderblocks and having a work engaging edge spaced from the non-magnetic material, said workholder'being adapted to receive metallic work so disposed on thework holder block which is spaced from the top gauge bar and overlying the non-magnetic material to engage said top gauge. bar whereby when said power unit is energized, magnetic flux passes through said blocks, work support, base, back to the power unit to fixedly secure said work to said fixture.

RICHARD G. NILL.

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

UNITED STATES PATENTS Number Name Date 1,336,928 Simmons Apr. 13, 1920 2,113,874 Chanik Apr. 12, 1938