SLIP-RELEASE LINEAR FORCE GAUGE FOR DETECTING COMPRESSION AND TENSION FORCES WHICH EXCEED A STANDARD FORCE

• US 3,848,463 A
• Filed: 04/20/1973
• Issued: 11/19/1974
• Est. Priority Date: 04/20/1973
• Status: Expired due to Term

• Current Assignee: Robert M. Zweig, Sid Hejzlar
• Original Assignee: Robert M. Zweig, Sid Hejzlar
• Inventors: Hejzlar, Sid, Zweig, Robert M.
• Primary Examiner(s): Gill, Jr., James J.
• Assistant Examiner(s): Ciarlante, Anthony V.
• Application Number:
  US05/352,966
• Time in Patent Office: 578 Days
• Field of Search: 73/141AB,141A,88B,15A
• US Class Current: 73/862.53
• CPC Class Codes: G01L 1/04 by measuring elastic deformation of gauges, e.g. of springs
• CPC Class Codes: G01L 5/0033 applying a pulling force
• CPC Class Codes: G01L 5/0038 applying a pushing force
• CPC Class Codes: G01L 5/0042 applying a torque

Abstract

A slip-release linear force gauge for detecting compression and tension forces which exceed a preselected standard force value by comparing two angularly opposing torques, one a preset standard torque, the other a test torque, which act upon the same balance arm about a common fulcrum point. The gauge includes a supporting frame having a fulcrum point, and a rigid balance arm pivotally mounted in the supporting frame about the fulcrum point. A spring coupled to one end of the rigid balance arm generates a standard torque about the fulcrum point by exerting a force which does not pass through the fulcrum point. An adjusting mechanism for variably preselecting the value of the standard torque generated by the spring force is provided. Stop means for limiting rotation of the rigid balance arm in response to the spring generated torque is also provided. A test force detector shaft is slidably mounted in the supporting frame and disengagably coupled to the other end of the rigid balance arm for generating a test torque in response to a test force applied to it. The slidable shaft is disposed to slip from its preset position when the test force applied to it generates a test torque which exceeds the preselected standard torque generated by the spring, thereby causing the rigid balance arm to rotate.

Claims

1. A slip-release linear force gauge for detecting compression and tension forces which exceed a predetermined standard force level comprising:

a supporting frame having a fulcrum point located therein, rigid balance arm means pivotally mounted in said supporting frame on said fulcrum point, means for generating a predeterMined standard torque acting upon said balance arm means in one direction about said fulcrum point, means for relating the predetermined standard torque to the predetermined standard force level against which tension and compression forces are tested, detector means slidably mounted in said supporting frame to assume a preset position and coupled to said balance arm means for generating a test torque in response to tension and compression forces applied to said detector means, the test torque acting upon said balance arm means about said fulcrum point in a direction opposed to the predetermined standard torque, said detector means being disposed to linearly slip from its preset position when the test torque exceeds the standard torque thereby indicating that the tension or compression force has exceeded the predetermined standard force level.

2. A slip-release linear force gauge for detecting compression and tension forces which exceed a predetermined force level comprising:

a supporting frame having a body with a fulcrum point disposed therein, a rigid balance arm having first and second extension portions with first and second ends respectively, pivotally mounted at the junction of said first and second extension portions on said fulcrum point, means for generating a predetermined linear force, arranged to act upon said first end of said balance arm to produce a predetermined standard torque about said fulcrum point, means for relating the predetermined linear force and the predetermined standard torque to the predetermined standard force level against which forces are tested, means for restraining said first balance arm extension to limit rotation of said balance arm in one direction under the influence of the predetermined standard torque and for positioning said balance arm in a preset attitude, a detector shaft longitudinally slidably mounted in said supporting frame, having an annular constricted neck for disengagably receiving said second end of said balance arm when in the preset attitude, said detector shaft being arranged to engage a test piece for generating a longitudinal test force to produce a test torque acting upon said second end of said balance arm about said fulcrum point, the test torque being opposed to the predetermined standard torque, said second balance arm end being disposed to disengage from said constricted shaft neck permitting said detector shaft to longitudinally, linearly slip from its preset attitude and permitting said balance arm to rotate from its preset attitude when the test torque exceeds the standard torque thereby indicating that the test force has exceeded the predetermined standard force level.

3. The slip-release linear force gauge as claimed in claim 2 wherein said predetermined linear force generating means is a spring, mounted so that the line of force of said spring does not intersect said fulcrum point when said balance arm is in its preset attitude, for generating the predetermined linear force between said first end of said rigid balance arm and said supporting frame to thereby generate the standard torque.

4. The slip-release linear force gauge as claimed in claim 2 wherein said second end of said rigid arm means is provided with antifriction bearing means to permit free disengagement of said second end and said constricted neck portion.

5. The slip-release linear force gauge as claimed in claim 2 having opposing rod means mounted in said supporting frame to limit transverse bending of said shaft when said second balance arm end disengages from said constricted neck and for creating retarding friction between said opposing rod and said detector shaft and between said second balance arm end and said detector shaft to retard linear travel of said detector shaft when said shaft slips under the influence of a test force exceeding the predetermined force level.

6. The slip-release linear force gauge as claimed in claim 2 wherein said predetermined linear force generatiNg means is provided with adjustment means for variably, selectively preselecting the linear force generated by said linear force generating means.

7. The slip-release linear force gauge as claimed in claim 6 wherein said predetermined linear force generating means is a spring, mounted so that the line of force of said spring does not intersect said fulcrum point when said balance arm is in its preset attitude, for generating a predetermined linear force between said rigid arm means and said adjustment means to thereby generate the standard torque.

8. The slip-release linear force gauge as claimed in claim 7 wherein said adjustment means comprises:

a bushing, having threaded bore, mounted in said spring, a threaded spindle rotatably mounted in said bushing threaded bore, a control knob mounted at one end of said spindle, on the exterior of said supporting frame, and pivoting restraining means for restraining said control knob on the exterior of said supporting frame and for pivoting said control knob and said spindle relative to said supporting frame to permit said spring to generate a linear tension force between said rigid arm means and said control knob.

9. The slip-release linear force gauge as claimed in claim 2 in which said means for relating the predetermined standard linear force and the predetermined standard torque to the predetermined standard force level against which test forces are tested comprises a scale and pointer, mounted in said supporting frame, calibrated so that the pointer indicates on the scale what test force applied to said detector shaft will cause said detector shaft to slip from its preset attitude.

10. The slip-release linear force gauge as claimed in claim 2 wherein said detector shaft has first and second ends, and wherein said first end carries a compression pad engaging a test piece to detect compression forces and said second end carries a tension hook for engaging a test piece to detect tension forces.

11. A slip-release linear force gauge for detecting compression and tension forces which exceed a predetermined force level comprising:

a supporting frame having a fulcrum point located therein, rigid balance arm means pivotally mounted in said supporting frame on said fulcrum point, means for generating a predetermined standard torque acting upon said balance arm means about said fulcrum point, said balance arm means and said standard torque generating means being arranged to generate a maximum predetermined standard torque within the range of pivoted travel of said balance arm means, means for relating the predetermined standard torque to the predetermined standard force level against which test forces are tested, means for limiting rotation of said balance arm means in one direction under the influence of the predetermined standard torque and for positioning said balance arm means in a preset attitude, said limiting means, said balance arm means and said standard torque generating means being arranged so that the maximum predetermined standard torque within the range of pivoted travel of said balance arm means is generated when said balance arm means is in its preset attitude, detector means slidably mounted in said supporting frame to assume a preset attitude and coupled to said balance arm means for generating a test torque in response to a test force applied to said detector means, the test torque being angularly opposed to the maximum predetermined standard torque and acting upon said balance arm means about said fulcrum point, said detector means being disposed to linearly slip from its preset attitude when the test torque exceeds the maximum predetermined standard torque thereby indicating that the test force has exceeded the standard force level.