Dial indicator with crowned gear

• US 5,682,682 A
• Filed: 04/25/1996
• Issued: 11/04/1997
• Est. Priority Date: 04/25/1996
• Status: Expired due to Term

• Current Assignee: MAHR Federal Incorporated
• Original Assignee: Federal Products Co (Transdigm Group Incorporated)
• Inventors: Renfrew, Greg, Windler, Hans
• Primary Examiner(s): Will, Thomas B.
• Application Number:
  US08/637,503
• Time in Patent Office: 558 Days
• Field of Search: 33/556, 33/559
• US Class Current: 33/556
• CPC Class Codes: G01B 3/22 Feeler-pin gauges, e.g. dial gauges for measuring contours or curvatures G01B5/20

Abstract

A dial indicator comprising a body having an dial face with marked graduations; a longitudinally reciprocating rod extending from the body, the rod having a standard rack internal to the body and an end of the rod external to the body having a contact surface; an interacting series of gear assemblies inside the body, one of the gear assemblies having a crowned pinion, the crowned pinion being driven by the rack; and a dial hand attached to the axle of another of the gears; whereby longitudinal pressure on the contact surface causes the rod to retract longitudinally into the body, the distance of retraction being indicated by the dial hand on the dial face.

Claims

1. A dial indicator comprising:

(a) a body having an dial face with marked graduations;

(b) a longitudinally reciprocating rod extending from said body, said rod having a standard rack internal to said body and an end of said rod external to said body having a contact surface;

(c) an interacting series of gear assemblies inside said body, one of said gear assemblies having a crowned pinion, said crowned pinion being driven by said rack; and

(d) a dial hand attached to the axle of another of said gear assemblies;

(e) whereby longitudinal pressure on said contact surface causes said rod to retract longitudinally into said body, the distance of retraction being indicated by said dial hand on said dial face.

2. The dial indicator of claim 1 wherein said dial face has 100 equally spaced graduations and the difference between two adjacent of said graduations indicates a distance in the range of from 0.00001 inch to 0.001 inch.

3. The dial indicator of claim 1 wherein said body includes a selectively rotating bezel, said bezel including a substantially transparent window through which said dial face is visible, and said bezel being selectively prohibited from rotating by a bezel clamp.

4. The dial indicator of claim 1 wherein said rod is biased out of said body when no longitudinal pressure is applied to said contact surface.

5. The dial indicator of claim 1 wherein said crowned pinion has a diametral pitch in the range of from approximately 120 to approximately 130.

6. The dial indicator of claim 1 wherein each tooth of said crowned pinion has a contact arc radius of curvature in the range of from approximately 1.4 inches to approximately 1.6 inches.

7. The dial indicator of claim 1 wherein said series of gear assemblies includes a conversion gear assembly, an intermediate gear assembly, and a center pinion, said crowned pinion being on said conversion gear assembly, said conversion gear assembly driving said intermediate gear assembly, and said intermediate gear assembly driving said center pinion, said dial hand attached to the axle of said center pinion.

8. The dial indicator of claim 7 wherein said series of gear assemblies includes a take up gear assembly having a hairspring, said center pinion driving said take up gear assembly causing said hairspring to be compressed when said rod is retracting into said body, and said hairspring uncompressing and causing said take up gear assembly to drive said center pinion when said rod is being projected out of said body, whereby the backlash between said gear assemblies is minimized.

9. A dial indicator comprising:

(a) a body having an dial face with 100 equally spaced marked graduations, the difference between two adjacent of said graduations indicating a distance in the range of from 0.00001 inch to 0.001 inch;

(b) said body including a selectively rotating bezel, said bezel including a substantially transparent window through which said dial face is visible, and said bezel being selectively prohibited from rotating by a bezel clamp;

(c) said body including a lower stem extending from said body;

(d) a longitudinally reciprocating rod having a standard rack internal to said body and an external end having a contact surface extending out of said lower stem;

(e) said rod being biased out of said body when no longitudinal pressure is applied to said contact surface;

(f) an interacting series of gear assemblies inside said body, one of said gear assemblies having a crowned pinion, said crowned pinion being driven by said rack; and

(g) a dial hand attached to the axle of another of said gears;

(h) whereby longitudinal pressure on said contact surface causes said rod to retract longitudinally into said body, the distance of retraction being indicated by said dial hand on said dial face.

10. The dial indicator of claim 9 wherein said crowned pinion has a diametral pitch in the range of from approximately 120 to approximately 130.

11. The dial indicator of claim 9 wherein each tooth of said crowned pinion has a contact arc radius of curvature in the range of from approximately 1.4 inches to approximately 1.6 inches.

12. The dial indicator of claim 9 wherein said series of gear assemblies includes:

(a) a conversion gear assembly, an intermediate gear assembly, a center pinion, and a take up gear assembly;

(b) said take up gear assembly having a hairspring;

(c) said crowned pinion being on said conversion gear assembly;

(d) said dial hand attached to the axle of said center pinion;

(e) said conversion gear assembly driving said intermediate gear assembly, said intermediate gear assembly driving said center pinion, and said center pinion driving said take up gear assembly when said rod is retracting into said body, causing said hairspring to be compressed; and

(f) said hairspring uncompressing and causing said take up gear assembly to drive said center pinion when said rod is being projected out of said body, whereby the backlash between said gear assemblies is minimized.

13. A dial indicator comprising:

(a) a body having an dial face with 100 equally spaced marked graduations, the difference between two adjacent of said graduations indicating a distance in the range of from 0.00001 inch to 0.001 inch;

(b) said body including a selectively rotating bezel, said bezel including a substantially transparent window through which said dial face is visible, and said bezel being selectively prohibited from rotating by a bezel clamp;

(c) said body including a lower stem extending from said body;

(d) a longitudinally reciprocating rod having a standard rack internal to said body and an external end extending out of said lower stem;

(e) said rod external end having a contact surface, said contact surface being composed of a wear-resistant material and being substantially smooth;

(f) said rod being biased out of said body when no longitudinal pressure is applied to said contact surface;

(g) a series of gear assemblies inside said body, said series including a conversion gear assembly, an intermediate gear assembly, a center pinion, and a take up gear assembly, said conversion gear assembly including a crowned pinion, a dial hand attached to the axle of said center pinion, and said take up gear assembly having a hairspring;

(h) said rack driving said crowned pinion, said conversion gear assembly driving said intermediate gear assembly, said intermediate gear assembly driving said center pinion, and said center pinion driving said take up gear assembly when said rod is retracting into said body, causing said hairspring to be compressed;

(i) said hairspring uncompressing and causing said take up gear assembly to drive said center pinion when said rod is being projected out of said body, whereby the backlash between said gear assemblies is minimized;

(j) said crowned pinion having a diametral pitch in the range of from approximately 120 to approximately 130; and

(k) each tooth of said crowned pinion having a contact arc radius of curvature in the range of from approximately 1.4 inches to approximately 1.6 inches;

(l) whereby longitudinal pressure on said contact surface causes said rod to retract longitudinally into said body, the distance of retraction being indicated by said dial hand on said dial face.

14. A dial indicator comprising:

(a) a body having an dial face with marked graduations;

(b) a longitudinally reciprocating rod extending from said body, said rod having a crowned rack internal to said body and an end of said rod external to said body having a contact surface;

(c) an interacting series of gear assemblies inside said body, said series being driven by said crowned rack; and

(d) a dial hand attached to the axle of one of said gear assemblies;

(e) whereby longitudinal pressure on said contact surface causes said rod to retract longitudinally into said body, the distance of retraction being indicated by said dial hand on said dial face.

15. The dial indicator of claim 14 wherein said dial face has 100 equally spaced graduations and the difference between two adjacent of said graduations indicates a distance in the range of from 0.00001 inch to 0.001 inch.

16. The dial indicator of claim 14 wherein said body includes a selectively rotating bezel, said bezel including a substantially transparent window through which said dial face is visible, and said bezel being selectively prohibited from rotating by a bezel clamp.

17. The dial indicator of claim 14 wherein said rod is biased out of said body when no longitudinal pressure is applied to said contact surface.

18. The dial indicator of claim 14 wherein each tooth of said crowned rack has a contact arc radius of curvature in the range of from approximately 1.4 inches to approximately 1.6 inches.

19. The dial indicator of claim 14 wherein said series of gear assemblies includes a conversion gear assembly, an intermediate gear assembly, and a center pinion, said crowned rack driving said conversion gear assembly, said conversion gear assembly driving said intermediate gear assembly, and said intermediate gear assembly driving said center pinion, said dial hand attached to the axle of said center pinion.

20. The dial indicator of claim 19 wherein said series of gear assemblies includes a take up gear assembly having a hairspring, said center pinion driving said take up gear assembly causing said hairspring to be compressed when said rod is retracting into said body, and said hairspring uncompressing and causing said take up gear assembly to drive said center pinion when said rod is being projected out of said body, whereby the backlash between said gear assemblies is minimized.

21. A dial indicator comprising:

(a) a body having an dial face with 100 equally spaced marked graduations, the difference between two adjacent of said graduations indicating a distance in the range of from 0.00001 inch to 0.001 inch;

(b) said body including a selectively rotating bezel, said bezel including a substantially transparent window through which said dial face is visible, and said bezel being selectively prohibited from rotating by a bezel clamp;

(c) said body including a lower stem extending from said body;

(d) a longitudinally reciprocating rod having a crowned rack internal to said body and an external end having a contact surface extending out of said lower stem;

(e) said rod being biased out of said body when no longitudinal pressure is applied to said contact surface;

(f) an interacting series of gear assemblies inside said body, said series being driven by said crowned rack; and

(g) a dial hand attached to one of said gear assemblies;

(h) whereby longitudinal pressure on said contact surface causes said rod to retract longitudinally into said body, the distance of retraction being indicated by said dial hand on said dial face.

22. The dial indicator of claim 21 wherein each tooth of said crowned rack has a contact arc radius of curvature in the range of from approximately 1.4 inches to approximately 1.6 inches.

23. The dial indicator of claim 21 wherein said series of gear assemblies includes:

(a) a conversion gear assembly, an intermediate gear assembly, a center pinion, and a take up gear assembly;

(b) said take up gear assembly having a hairspring;

(c) said dial hand attached to the axle of said center pinion;

(d) said crowned rack driving said conversion gear assembly, said conversion gear assembly driving said intermediate gear assembly, said intermediate gear assembly driving said center pinion, and said center pinion driving said take up gear assembly when said rod is retracting into said body, causing said hairspring to be compressed; and

(e) said hairspring uncompressing and causing said take up gear assembly to drive said center pinion when said rod is being projected out of said body, whereby the backlash between said gear assemblies is minimized.

24. A dial indicator comprising:

(a) a body having an dial face with 100 equally spaced marked graduations, the difference between two adjacent of said graduations indicating a distance in the range of from 0.00001 inch to 0.001 inch;

(b) said body including a selectively rotating bezel, said bezel including a substantially transparent window through which said dial face is visible, and said bezel being selectively prohibited from rotating by a bezel clamp;

(c) said body including a lower stem extending from said body;

(d) a longitudinally reciprocating rod having a crowned rack internal to said body and an external end having a contact surface extending out of said lower stem;

(e) each tooth of said crowned rack having a contact arc radius of curvature in the range of from approximately 1.4 inches to approximately 1.6 inches;

(f) said rod being biased out of said body when no longitudinal pressure is applied to said contact surface;

(g) a series of gear assemblies inside said body, said series including a conversion gear assembly, an intermediate gear assembly, a center pinion, and a take up gear assembly, a dial hand attached to the axle of said center pinion, and said take up gear assembly having a hairspring;

(h) said crowned rack driving said conversion gear assembly, said conversion gear assembly driving said intermediate gear assembly, said intermediate gear assembly driving said center pinion, and said center pinion driving said take up gear assembly when said rod is retracting into said body, causing said hairspring to be compressed;

(i) said hairspring uncompressing and causing said take up gear assembly to drive said center pinion when said rod is being projected out of said body, whereby the backlash between said gear assemblies is minimized;

(j) whereby longitudinal pressure on said contact surface causes said rod to retract longitudinally into said body, the distance of retraction being indicated by said dial hand on said dial face.