Instrument for non-contact infrared temperature measurement having current clamp meter functions

• US 7,163,336 B2
• Filed: 08/04/2004
• Issued: 01/16/2007
• Est. Priority Date: 08/04/2003
• Status: Active Grant

• Current Assignee: FLIR Systems, Inc. (Teledyne Technologies Incorporated)
• Original Assignee: Extech Instruments Corporation (Teledyne Technologies Incorporated)
• Inventors: Blakeley, Gerald W III
• Primary Examiner(s): Verbitsky; Gail
• Application Number:
  US10/910,894
• Publication Number:
  US 20050031013A1
• Time in Patent Office: 895 Days
• Field of Search: 374/130, 374/120, 374/121, 374/208, 374/141, 374/183, 374/163, 374/132, 374/142
• US Class Current: 374/142
• CPC Class Codes: G01J 5/02 Constructional details
• CPC Class Codes: G01J 5/026 Control of working procedures of a pyrometer, other than calibration; Bandwidth calculation; Gain control
• CPC Class Codes: G01J 5/0265 Handheld, portable ear thermometers G01J5/049
• CPC Class Codes: G01J 5/04 Casings
• CPC Class Codes: G01J 5/07 Arrangements for adjusting the solid angle of collected radiation, e.g. adjusting or orienting field of view, tracking position or encoding angular position optical collimating elements G01J5/0806
• CPC Class Codes: G01J 5/08 Optical arrangements
• CPC Class Codes: G01J 5/0801 Means for wavelength selection or discrimination
• CPC Class Codes: G01J 5/0846 having multiple detectors for performing different types of detection, e.g. using radiometry and reflectometry channels
• CPC Class Codes: G01R 1/06788 Hand-held or hand-manipulated probes, e.g. for oscilloscopes or for portable test instruments end pieces terminating in a probe H01R11/18
• CPC Class Codes: G01R 1/22 Tong testers acting as secondary windings of current transformers
• CPC Class Codes: G01R 15/186 using current transformers with a core consisting of two or more parts, e.g. clamp-on type G01R15/142 - G01R15/16 take precedence; tong testers G01R1/22

Abstract

A handheld instrument that accomplishes infrared (IR) temperature measurement and non-contact electrical current measurement. The instrument has a case, a current-sensing device coupled to the case and operable to be placed around a conductor, for generating an output signal based on the current flowing through the conductor, and an IR detector carried by the case, for sensing IR energy emitted from a surface being measured along a sensing axis that extends from the case, and generating an IR output signal. Sensed IR energy is converted to a temperature value, and the output signal from the current-sensing device is converted to at least a measured current value. There is a display device in the case, for displaying instrument measurements to the user.

Claims

1. A handheld instrument that accomplishes infrared (IR) temperature measurement and non-contact electrical current measurement, comprising:

a case having a top and an end;

a current-sensing device coupled to the case comprising a clamp extending outward from said end of the case and operable to be placed around a conductor, for generating an output signal based on the current flowing through the conductor;

an IR detector carried by the case, for sensing IR energy emitted from a surface being measured along a sensing axis that extends from said end of the case, and generating an IR output signal;

means for converting sensed IR energy to a temperature value, and for converting the output signal from the current-sensing device to at least a measured current value; and

a display device in the case and visible at the top of the case, for displaying instrument measurements to the user.

2. The handheld instrument of claim 1, further comprising an aiming device carried by the case for emitting a visible beam along an aiming axis, to assist the operator in aiming the IR detector.

3. The handheld instrument of claim 2, wherein the aiming device comprises a laser diode.

4. The handheld instrument of claim 2, wherein the aiming axis is close to the sensing axis and also extends from the end of the case.

5. The handheld instrument of claim 4, wherein the aiming axis and the sensing axis are essentially parallel to one another.

6. The handheld instrument of claim 4, wherein the aiming axis and sensing axis are fixed at a slight angle to one another.

7. The handheld instrument of claim 1, wherein the means for converting sensed IR energy to a temperature accomplishes a fixed emissivity.

8. The handheld instrument of claim 1, wherein the means for converting comprises an analog to digital converter for digitizing the current-sensing device output signal and the IR output signal.

9. The handheld instrument of claim 1, further comprising means for maintaining a sensed temperature on the display device until after the IR detector is no longer aimed at the surface being measured.

10. The handheld instrument of claim 1, further comprising a power source carried within the case, for supplying power to at least the IR detector, the means for converting, and the display device.

11. The handheld instrument of claim 10, wherein the power source comprises a DC power source.

12. The handheld instrument of claim 11, wherein the DC power source comprises a battery.

13. The handheld instrument of claim 1, further comprising switch means to control which signal is displayed.

14. The handheld instrument of claim 1, wherein the display device is a digital display device.

15. The handheld instrument of claim 1, wherein the display device is an analog display device.

16. A handheld instrument that accomplishes infrared (IR) temperature measurement and non-contact electrical current measurement, comprising:

a case having a top and an end;

a current-sensing device coupled to the case comprising a clamp extending outward from said end of the case and operable to be placed around a conductor, for generating an output signal based on the current flowing through the conductor;

an IR detector carried by the case, for sensing IR energy emitted from a surface being measured along a sensing axis that extends from said end of the case, and generating an IR output signal;

a laser diode aiming device carried by the case for emitting a visible beam along an aiming axis that extends from said end of the case, to assist the operator in aiming the IR detector;

means for converting sensed IR energy to a temperature value using a fixed emissivity, and for converting the output signal from the current-sensing device to at least a measured current value;

a display device in the case and visible at the top of the case, for displaying instrument measurements to the user; and

a battery power source carried within the case, for supplying power to at least the IR detector, the laser diode, the means for converting, and the display device.

17. The handheld instrument of claim 16, wherein the fixed emissivity is about 0.95.

18. The handheld instrument of claim 16, wherein the aiming axis is close to the sensing axis.

19. The handheld instrument of claim 18, wherein the aiming axis and the sensing axis are essentially parallel to one another.

20. The handheld instrument of claim 18, wherein the aiming axis and sensing axis are fixed at a slight angle to one another.