Multimeter with non-contact temperature measurement

• US 7,056,012 B2
• Filed: 09/04/2003
• Issued: 06/06/2006
• Est. Priority Date: 10/03/2002
• Status: Expired due to Term

• Current Assignee: FLIR Systems, Inc. (Teledyne Technologies Incorporated)
• Original Assignee: Extech Instruments Corporation (Teledyne Technologies Incorporated)
• Inventors: Blakeley, Gerald W. III
• Primary Examiner(s): Guadalupe, Yaritza
• Application Number:
  US10/654,851
• Publication Number:
  US 20040066833A1
• Time in Patent Office: 1,006 Days
• Field of Search: 374120-121, 374/128, 374/130, 374/142, 374/208
• US Class Current: 374/120
• CPC Class Codes: G01J 5/041 Mountings in enclosures or in a particular environment
• CPC Class Codes: G01J 5/08 Optical arrangements
• CPC Class Codes: G01J 5/0846 having multiple detectors for performing different types of detection, e.g. using radiometry and reflectometry channels

Abstract

A multimeter with non-contact temperature measurement capability. The multimeter is contained in a housing, and has outputs relating to measured electrical parameters. There is also an output display contained in the housing, for displaying results to a user. A non-contact optically-based temperature sensing device is coupled to the housing, and has an output related to sensed temperature. Circuitry contained in the housing processes both the multimeter outputs and the temperature sensing device output, and transmits the processed output to the output display.

Claims

1. A multimeter with non-contact temperature measurement capability, comprising:

a multimeter contained in a housing and having outputs relating to measured electrical parameters;

an output display contained in the housing, for displaying results to a user;

a non-contact optically-based temperature sensing device comprising an infrared sensor built in to the housing, having an output related to sensed temperature of a surface, and without the capability of adjusting for emissivity of the surface being sensed, the temperature sensing device defining a sense axis that is adjustable relative to the housing, and further comprising a lens, proximate the infrared sensor and mounted in a mount that is coupled to and projects outwardly from the housing, for focusing entering radiation and protecting the infrared sensor, wherein the mount is movable by the user relative to the housing, to allow the user to aim the sense axis; and

circuitry contained in the housing for processing both the multimeter outputs and the temperature sensing device output, in which the circuitry determines the sensed temperature based on the output of the temperature sensing device using a fixed emissivity value, the circuitry transmitting the processed output to the output display.

2. The multimeter with non-contact temperature measurement capability of claim 1 in which the mount is rotatably coupled to the housing.

3. The multimeter with non-contact temperature measurement capability of claim 1 further comprising an optical aiming device coupled to the housing, to assist the user in aiming the temperature sensing device at an object whose temperature is to be measured.

4. The multimeter with non-contact temperature measurement capability of claim 3 in which the optical aiming device comprises a laser that is adjustable relative to the housing.

5. The multimeter with non-contact temperature measurement capability of claim 4 in which the optical aiming device is mounted in the mount that is coupled to and projects outwardly from the housing, to allow the user to aim the optical aiming device.

6. The multimeter with non-contact temperature measurement capability of claim 5 in which the mount is rotatably coupled to the housing.

7. The multimeter with non-contact temperature measurement capability of claim 3 in which the optical aiming device comprises a diode laser device.

8. The multimeter with non-contact temperature measurement capability of claim 1 further comprising a switch for switching at least some of the circuitry between the multimeter outputs and the temperature sensing device output.

9. The multimeter with non-contact temperature measurement capability of claim 1 further comprising a user-operable electrical device for selectively routing the temperature sensing device output to the circuitry.

10. The multimeter with non-contact temperature measurement capability of claim 1 further comprising a user-operable electrical device for selectively holding the sensed temperature.

11. The multimeter with non-contact temperature measurement capability of claim 1 in which the fixed emissivity value is about 0.95.

12. A digital multimeter with non-contact temperature measurement capability, comprising:

a digital multimeter contained in a housing and having outputs relating to measured electrical parameters;

a digital output display contained in the housing, for displaying results to a user;

a non-contact infrared temperature sensing device contained within the housing, having an output related to sensed temperature of a surface, and without the capability of adjusting for emissivity of the surface being sensed, the temperature sensing device defining a sense axis that is adjustable relative to the housing and further comprising at least a lens that is mounted in a mount that projects outwardly from the housing, and is coupled to and movable by the user relative to the housing, to allow the user to aim the temperature sensing device sense axis; and

circuitry contained in the housing for processing both the multimeter outputs and the temperature sensing device output, in which the circuitry determines the sensed temperature based on the output of the temperature sensing device using a fixed emissivity value, the circuitry transmitting the processed output to the output display.

13. The multimeter with non-contact temperature measurement capability of claim 12 in which the mount is rotatably coupled to the housing.

14. The multimeter with non-contact temperature measurement capability of claim 12 further comprising an optical aiming device coupled to the housing, to assist the user in aiming the temperature sensing device at an object whose temperature is to be measured.

15. The multimeter with non-contact temperature measurement capability of claim 14 in which the optical aiming device comprises a laser that is adjustable relative to the housing.

16. The multimeter with non-contact temperature measurement capability of claim 15 in which the optical aiming device is mounted in the mount that is coupled to and projects outwardly from the housing, to aim the optical aiming device.

17. The multimeter with non-contact temperature measurement capability of claim 16 in which the mount is rotatably coupled to the housing.

18. The multimeter with non-contact temperature measurement capability of claim 12 in which the fixed emissivity value is about 0.95.