Tool monitor and assembly qualifier

• US 6,055,484 A
• Filed: 04/20/1999
• Issued: 04/25/2000
• Est. Priority Date: 09/17/1997
• Status: Expired due to Term

• Current Assignee: CE Electronics, Inc.
• Original Assignee: CE Electronics, Inc.
• Inventors: Lysaght, Richard G.
• Primary Examiner(s): ASSOUAD, PATRICK J
• Application Number:
  US09/294,511
• Time in Patent Office: 371 Days
• Field of Search: 702/138, 702/41, 702/114, 702/115, 702/182, 702/113, 364/468.01, 173/177, 173/178, 173/180, 173/181, 91/59, 91/1, 81/470, 227/130, 73/862.23, 73/1.12, 73/1.57, 73/1.59, 73/862.21
• US Class Current: 702/41
• CPC Class Codes: B23P 19/066 by electrical means
• CPC Class Codes: B25B 23/14 Arrangement of torque limiters or torque indicators in wrenches or screwdrivers couplings for transmitting rotation or clutches F16D; devices for measuring torque per se G01L

Abstract

This counting apparatus is a tool monitor and assembly qualifier that verifies that the correct number of fasteners have been properly installed into an assembly. When used in conjunction with a pressure tool, proper fastener torque and count can be verified. The device monitors internal tool pressures and has the ability to "learn" the pressure characteristics of the tool during the assembly process. This assembly qualifier is a device that monitors either the pressure of an air tool, the current of an electrical tool or the torque of a mechanical wrench to determine if the tool shut off at a target torque. The qualifier also determines if some unknown means shuts off the tool.

Claims

1. A system for monitoring an electrically driven tool having a forward or reverse current flow through the tooling comprising:

a current transducer for measuring and converting the forward and reverse currents into electrical signals representative the measured currents;

means for electrically computationally processing the electrical signals into other signals representing at least one parameter corresponding to a condition of the tool being monitored which is a function of the current, wherein the means for electrically processing the signals includes a programmable microprocessor configured to identify a portion of the signals representative of the current corresponding to the parameter

a means for displaying the parameter;

wherein the programmed microprocessor is configured to identify a portion of the signals representative of the currents of the tool driving a fastener to its target torque and successfully completing a cycle; and

wherein the programmed microprocessor is configured to count a completed cycle, store the count and generate signals when the measured current is the same as the identified and stored parameters.

2. A system according to claim 1 wherein the programmed microprocessor is configured to identify and store a portion of the forward current and the reverse current as calibration values.

3. A system according to claim 1 wherein the programmed microprocessor is configured to identify and store the parameter of a threshold corresponding to both the forward current and the reverse current.

4. A system according to claim 1 wherein the programmed microprocessor is configured to identify and store the parameter of a first period of time for forward and reverse currents to attain a first predetermined range and is also configured to identify and store a second period of time for the forward and reverse currents to attain a second predetermined range.

5. A system according to claim 1 wherein the programmed microprocessor is configured to identify a portion of the signals representative of currents of the tool driving a fastener and not reaching target torque and unsuccessfully completing a cycle wherein the programmed microprocessor is configured to generate signals when a cycle is completed unsuccessfully.

6. A system according to claim 1 wherein the programmable microprocessor is configured to identify a portion of the signals representative of the currents of the tool driving a fastener that has previously been tightened to the target torque wherein the programmed microprocessor is configured to generate signals when a fastener has been previously tightened.

7. A system for monitoring a mechanical torque wrench with torque switch comprising:

means for electrically stimulating the switch wherein the torque switch can provide an electrical signal upon reaching target torque;

means for electrically computationally processing the electrical signal into other signals representing at least one parameter corresponding to a condition of the tool being monitored which is a function of the condition, wherein the means for electrically processing the other signals includes a programmed microprocessor configured to identify a portion of the other signals representative of the switch condition corresponding to the parameter

a means for displaying the parameters;

wherein the programmed microprocessor is configured to identify a portion of the other signals representative of the electrical signal of the tool driving a fastener to its target torque and successfully completing a cycle; and

wherein the programmed microprocessor is configured to count a completed cycle, store the count and generate signals when the measured signal is the same as the identified and stored parameter.

8. A system according to claim 7 wherein the programmed microprocessor is configured to identify and store a portion of the electrical signal as a calibration value.

9. A system according to claim 8 wherein the programmed microprocessor is configured to identify and store the parameter of a threshold corresponding to the calibration value.

10. A system according to claim 7 wherein the programmed microprocessor is configured to identify and store the parameter of a first period of time for the electrical signal to attain a predetermined level and also configured to identify and store a second period of time for the electrical signal to remain at that level.

11. A system according to claim 7 wherein the programmed microprocessor is configured to generate signals when a cycle is completed unsuccessfully.

12. A system according to claim 7 wherein the programmed microprocessor is configured to generate signals when a fastener has been previously tightened.