Method of calibrating torque using peak hold measurement on an electronic torque wrench

Patent metadata

Field	Value
Publication number	US-9839997-B2
Application number	US-201514946023-A
Country	US
Kind code	B2
Filing date	Nov 19, 2015
Priority date	May 7, 2013
Publication date	Dec 12, 2017
Grant date	Dec 12, 2017

Abstract

The present disclosure relates to an electronic torque tool, a calibration fixture, and a method for calibrating the electronic torque tool. The calibration includes applying a torque to the torque wrench and releasing the applied torque once the applied torque reaches a full scale calibration torque. The calibration fixture holds and displays a peak value of the applied torque and the torque wrench holds and displays a measured peak value of the applied torque. The measured peak value on the torque wrench may then be adjusted, by incrementing or decrementing the displayed value, to match the peak value displayed on the calibration fixture.

First claim

What is claimed is:

1. A tool having a drive head adapted to apply a torque, a handle extending from the drive head, and a sensor operably coupled to the drive head and adapted to measure an amount of the torque applied by the drive head, comprising:
a memory; and
a processor including instructions to:
measure, with the sensor, a peak amount of torque applied by the drive head to a calibration fixture, thereby creating a peak tool measured torque value;
store the peak tool measured torque value in the memory after the amount of torque applied to the calibration fixture is released; and
apply a calibration factor to the peak tool measured torque value to cause the peak tool measured torque value to match a calibration measured torque value representing the amount of the torque applied by the drive head to the calibration fixture measured by the calibration fixture.

2. The tool of claim 1 , wherein the memory is adapted to store the calibration factor.

3. The tool of claim 1 , further comprising an interface adapted to transmit data to and receive data from an external source.

4. The tool of claim 1 , wherein the processor further includes instructions to generate the calibration factor.

Assignees

• Snap On Incorporated

Inventors

• King Jerry A
• Lawton Chris
• Vallejos Duane A

Classifications

• G01L25/003

  for measuring torque · CPC title

• B25B23/1422

  torque indicators or adjustable torque limiters · CPC title

• B25B23/1425 Primary

  by electrical means · CPC title

• G01D18/008

  with calibration coefficients stored in memory · CPC title

• B25B23/147

  specially adapted for electrically operated wrenches or screwdrivers · CPC title