GB874669A - Wire holding attachment for three-wire method of measuring threads - Google Patents

Abstract

874,669. Thread-measuring attachments. STANDARD GAGE CO. Inc. May 11, 1959, No. 16105/59. Class 106 (2). Attachments to adapt dial, micrometer, caliper and similar gauges to the three-wire method of thread-gauging comprise a pair of annular plates 45, 56 through the central apertures of which the anvils 17, 11 of the gauge project, the plate 45 carrying the single diametral wire 48 and the plate 56 carrying the two wires 58 and anvils making contact with the respective wires. The plates have integral ears 47, 57 bored with holes of diameter slightly larger than that of the wires 48, 58 so that the wires can conform to the helical angle of the threads. Spring retaining washers 50, 61 extending around the plates have ears 51 which prevent the gauge wires from sliding axially. The plate 56 which is split at 60 is fixed frictionally to the lower anvil 11, and the plate 46 has opposite holes 52 to take the lower ends of coil springs 53 which at their upper ends are fixed to a U-shaped saddle 54 positioned in a slot 55 in the gauge frame 10. The lower anvil 11 has a threaded shank 12 on which is a nut 13 in a slot 14 in the lower arm of the frame 10, rotation of the nut raising or lowering the anvil. In the upper arm of frame 10 is mounted reciprocably the anvil 17 screwed to the top of which is a washer 28 an extension of which operates a T-shaped lever 27 engaging the measuring plunger 22 of a dial indicator 23. A spring 38 bears on the washer 28 with a pressure predetermined by screwing down on an insert screwed into a sleeve 36 co-operating with a scale 37 on a tubular member 32 integral with a cover member 31. To retract the upper anvil when inserting or removing the workpiece a lever 41 is pivoted to the frame 10 and engages a collar 43 on the anvil, the other end of the lever being formed as a thumb-piece 44. The attachments may be fitted to an ordinary micrometer gauge, the spring 53 and saddle 54 then taking over the yoke of the gauge. Specification 772,118 is referred to.