MAGNETICALLY HELD MEASURING AND LOCATING FIXTURES

• US 3,723,928 A
• Filed: 03/19/1971
• Issued: 03/27/1973
• Est. Priority Date: 05/05/1969
• Status: Expired due to Term

• Current Assignee: Alexander G. Blakey, Jack S. Adams, James J. Swarts
• Original Assignee: Alexander G. Blakey, Jack S. Adams, James J. Swarts
• Inventors: Blakey, Alexander G., Adams, Jack S., Swarts, James J.
• Primary Examiner(s): Harris, George
• Application Number:
  US05/126,021
• Time in Patent Office: 739 Days
• Field of Search: 335/285,286,293,294,295,302,306 33/DIG.1,174TA 269/304,306
• US Class Current: 335/285
• CPC Class Codes: B23Q 16/08 having means for clamping the relatively movable parts together in the indexed position
• CPC Class Codes: B23Q 3/107 with positive adjustment means
• CPC Class Codes: B23Q 3/1546 using permanent magnets
• CPC Class Codes: H01F 7/0252 PM holding devices H01F7/021, H01F7/0215, H01F7/0226 take precedence
• CPC Class Codes: Y10S 33/01 Magnetic
• CPC Class Codes: Y10T 29/49771 Quantitative measuring or gauging
• CPC Class Codes: Y10T 408/03 Processes
• CPC Class Codes: Y10T 409/303752 Process
• CPC Class Codes: Y10T 409/308624 with limit means to aid in positioning of cutter bit or work [e.g., gauge, stop, etc.]

Abstract

Fixtures for use in measuring and locating systems utilizing surface plates and methods of assemblying the fixtures are disclosed. A plate having a plurality of recesses of uniform sizes and shapes spaced across the surface is provided. Fixture bodies carrying gages or locating means are bonded to one or more support members which are shaped to seat in the recesses. The fixtures may be easily removed and replaced, with the recesses providing precise realignment. Preferred recess members and support members are also described in detail.

Claims

1. In a measuring and locating system comprising a plate having a smooth surface, a plurality of recesses of substantially uniform size and shape spaced across said surface, at least some of said recesses having cooperating magnetic attraction means adjacent thereto below the plate surface and at least one fixture adapted to cooperate with said recesses, the improvement wherein at least one ferromagnetic support member is secured to said fixture in a supporting relationship, each of said at least one support members having an exterior shape corresponding to each of said plurality of uniform recesses, whereby a support member is seatable in any of said recesses to hold said fixture in a desired position on said plate and is held by magnetic attraction against accidental displacement.

2. The improvement according to claim 1 wherein said fixture is secured to a single support member which has a shape permitting rotation in a plane parallel to said plate surface while seated in a recess.

3. The improvement according to claim 1 wherein said fixture is secured to at least two support members all of which are located in a substantially straight line, said support members having shapes permitting rotation around an axis drawn through said support members parallel to said plate surface, whereby said fixture may be pivoted around said axis.

4. The improvement according to claim 3 wherein further independent support members are seated in recesses adjacent to said axis, to support said fixture against further rotation in that direction, while permitting said fixture to be pivoted away from said independent support members in the opposite direction.

5. The improvement according to claim 1 wherein said fixture is secured to at least four support members, no more than two of which are located along a single straight line, whereby said fixture is held in a stable position relative to said plate surface.

6. The improvement according to claim 1 wherein at least a portion of each recess is spherical in shape and each support member has a spherical portion adapted to seat thereagainst.

7. The improvement according to claim 1 wherein each recess is conical in shape and each support member has a frusto-conical shape adapted to seat thereagainst.

8. The improvement according to claim 1 wherein each recess is cylindrical in shape and each support member has a chamfered cylindrical shape adapted to seat thereagainst.

9. A support member for a measuring and locating fixture comprising:

a. a ferromagnetic sphere, b. a thin flat sheet having an aperture therethrough, said sheet bonded to said sphere with said sphere extending into and through said aperture, said sphere in contact with the first planar surface of said sheet and extending from about 0.002 to about 0.008 inch beyond the opposite planar surface of said sheet.

10. The support member according to claim 9 wherein said sheet is in the form of a thin flat toroid.

11. The support member according to claim 9 wherein said sphere has a surface layer having a thickness of from about 0.00001 to about 0.0002 inch selected from the group consisting of chromium and fluorocarbon resins.

12. The support member according to claim 9 wherein said sheet is bonded to said sphere by a fused metal interlayer.

13. The support member according to claim 12 wherein said sheet is brazed to said sphere.

14. In a measuring system comprising a plate having a substantially planar surface, a plurality of spaced recesses of substantially uniform size and shape spaced across said surface, at least some of saiD recesses having cooperating magnetic attraction means adjacent thereto, and at least one measuring fixture mounted on at least one support member seated in said recesses, the improvement wherein each of said support members comprises a ferromagnetic sphere seated in a complementary recess, and each sphere is bonded to an apertured thin flat sheet with said sphere extending through said aperture, said sphere being in contact with the first planar surface of said sheet and extending from about 0.002 to about 0.008 inch beyond the opposite planar surface of said sheet.

15. The improvement according to claim 14 wherein said sheet is in the form of a thin flat toroid.

16. The improvement according to claim 14 wherein said sheet is bonded to said sphere by a fused metal interlayer.

17. An insert member for a measuring and locating system comprising:

a. a tube;

b. a substantially rectangular permanent magnet substantially centered in said tube;

c. two bars of ferromagnetic material on opposite sides of said magnet, extending the length of said tube between said magnet and the inner tube wall;

d. a filler block of non-magnetic material between said magnet and one end of said tube;

e. the remaining space within said tube substantially filled with a non-magnetic material which supports said bars and magnet in position;

f. said filler block and adjacent ends of said bars being recessed to receive a protruding member of complementary shape.

18. The insert member according to claim 17 wherein said two bars comprise a ferromagnetic stainless steel and said filler block comprises a substantially non-magnetic stainless steel.

19. The insert member according to claim 17 wherein said recess is spherical in shape, and further includes a deeper recessed portion at about the center of the spherical recess, whereby small amounts of foreign material in the deeper recess will not interfere with seating of a spherical protruding member seated against said spherical recess.