Proximity sensor resistant to environmental effects

• US 6,617,845 B1
• Filed: 04/28/2000
• Issued: 09/09/2003
• Est. Priority Date: 04/28/2000
• Status: Expired due to Term

• Current Assignee: Rockwell Technologies, LLC (Teledyne Technologies Incorporated)
• Original Assignee: Rockwell Automation Technologies Incorporated (Rockwell Automation, Inc.)
• Inventors: Kayserman, Isak, Shafiyan-Rad, Saeed, Fischer, Larry Joseph
• Primary Examiner(s): Strecker, Gerard R.
• Application Number:
  US09/561,025
• Time in Patent Office: 1,229 Days
• Field of Search: 324/207.26, 324/207--20, 324/236, 219/50, 219/124.1, 219/124.34, 219/124.4, 219/130.01, 228/218, 174/52-- 5, 307/116, 307/117, 901/35, 901/42, 901/46
• US Class Current: 324/207.16
• CPC Class Codes: G01D 11/245 Housings for sensors
• CPC Class Codes: H03K 17/945 Proximity switches H03K17/96 takes precedence

Abstract

A housing for a proximity sensor is resistant to harsh environmental effects, such as scorching particles due to sputtering in a welding environment. The sensor housing is formed of a material having a high thermal conductivity, such as copper or an alloy thereof. As a result, the housing is able to rapidly dissipate heat and, in turn, mitigate weld slag build-up so as to improve the efficacy of the sensor.

Claims

1. A proximity sensor, comprising:

an elongated circular cylindrical sidewall portion formed of a material comprising copper and having spaced apart ends, the material having a thermal conductivity of at least about three Watts per centimeter per Kelvin; and

proximity sensing circuitry located within the sidewall portion, the proximity sensor being operative to sense proximity of an object through one of the ends of the sidewall,

wherein the sidewall portion is threaded about an axis extending longitudinally through the sensor housing, whereby when the proximity sensor is employed in a welding environment, slag build-up is mitigated.

2. The proximity sensor of claim 1, wherein the sidewall portion is formed of a copper alloy.

3. The proximity sensor of claim 1, wherein the sensing circuitry further comprises an inductive proximity sensing device.

4. A proximity sensor, comprising:

sensing circuitry for sensing the proximity of an object; and

an elongated circular cylindrical externally threaded housing formed of a material having a thermal conductivity of at least about three Watts per centimeter per Kelvin and having spaced apart ends for receiving the proximity sensing circuitry therein;

whereby when the proximity sensor is employed in a welding environment, slag build up on the housing is mitigated.

5. The proximity sensor of claim 4, wherein the housing is copper.

6. The proximity sensor of claim 4, wherein the sensing circuitry further comprises an inductive proximity sensing device.

7. The proximity sensor of claim 6, wherein the sensing circuitry includes an inductor coil and associated circuitry mounted to a circuit board and located adjacent to a sensing end.

8. The proximity sensor of claim 4, wherein the housing is in the form of a cylindrical sleeve for receiving a body portion of the proximity sensor, the cylindrical sleeve being at least coextensive with an outer sidewall of the body portion.

9. The proximity sensor of claim 4, wherein the housing has a sensing end and a connector end, the connector end having a connector for receiving and connecting to a desired cable.

10. The proximity sensor of claim 9, the connector being a male connector.

11. The proximity sensor of claim 9, the connector being a female connector.