Temperature indicator bolts

• US 3,877,411 A
• Filed: 01/02/1974
• Issued: 04/15/1975
• Est. Priority Date: 07/16/1973
• Status: Expired due to Term

• Current Assignee: John A. Macdonald
• Original Assignee: John A. Macdonald
• Inventors: MacDonald, John A.
• Primary Examiner(s): Queisser, Richard C.
• Assistant Examiner(s): Appleman, John S.
• Application Number:
  US05/429,932
• Time in Patent Office: 468 Days
• Field of Search: 116/101,114V,106,114.5 73/356
• US Class Current: 116/207
• CPC Class Codes: F16C 19/386 in O-arrangement
• CPC Class Codes: F16C 19/525 related to temperature and heat, e.g. insulation
• CPC Class Codes: F16C 2326/10 Railway vehicles in general B61
• CPC Class Codes: F16C 25/06 Ball or roller bearings
• CPC Class Codes: F16C 41/008 Identification means, e.g. markings, RFID-tags; Data transfer means
• CPC Class Codes: G01K 1/14 Supports; Fastening devices; Arrangements for mounting thermometers in particular locations

Abstract

A temperature indicator bolt comprising a securable shank and an engageable head having an outer surface. A cavity is provided in the outer surface and contains a wafer type indicator element therein. The indicator element is impregnated, at least partly, with a chemical substance having indicating properties responsive to temperature. A transparent protective covering is provided over said wafer type indicator.

Claims

1. A temperature indicator bolt for use in an end cap of a roller bearing mounting on an axle, said bolt comprising a securable shank and an engageable head having an outer surface;

a shallow depression in a substantial portion of the surface area of said outer surface;

a wafer type indicator element retained in said shallow depression;

said indicator element being provided with at least two sections, one of said sections being responsive to a predetermined overheating temperature and the other to another predetermined temperature lower than said overheating temperature;

each said sections being impregnated, at least partly, with a chemical substance having indicating properties responsive to said predetermined temperature of said section whereby the color of said substance will change and remain changed when said bolt is subjected to said predetermined temperature, and a transparent protective covering over said wafer type indicator to removably secure said indicator element in said shalloW depression.

2. A temperature indicator bolt as claimed in claim 1 wherein said wafer type indicator element is adhesively secured to a backing element having a different color whereby to constitute said peripheral band about said indicator element to more readily identify said indicator element.

3. A temperature indicator bolt as claimed in claim 1 wherein said sections are each provided with a marking indicating the temperature to which the chemical substance of the section is responsive.

4. A temperature indicator bolt as claimed in claim 1 wherein said transparent protective covering is a plastic film adhesively secured over said indicator element and entirely sealing said cavity.

5. A temperature indicator bolt as claimed in claim 1 wherein a peripheral band is provided about said indicator element and of a contrasting color to said indicator element when it has been subjected to a change of color due to overheating when said predetermined temperature is reached.