Pad wear and pad wear indicator probe

• US 5,608,376 A
• Filed: 06/24/1994
• Issued: 03/04/1997
• Est. Priority Date: 08/06/1993
• Status: Expired due to Term

• Current Assignee: Sumitomo Wiring Systems Limited (Sumitomo Corporation)
• Original Assignee: Sumitomo Wiring Systems Limited (Sumitomo Corporation)
• Inventors: Ito, Katsuya, Takanashi, Hitoshi
• Primary Examiner(s): Hofsass, Jeffery
• Assistant Examiner(s): Pope, Daryl C.
• Application Number:
  US08/265,112
• Time in Patent Office: 984 Days
• Field of Search: 340/453, 340/454, 116/208, 200/61.4, 73/121, 1/129
• US Class Current: 340/454
• CPC Class Codes: F16D 66/026 indicating different degrees of lining wear
• CPC Class Codes: F16D 66/027 Sensors therefor

Abstract

A brake pad wear probe contains a plurality of terminals turned or bent into a U-shape with their tip positions offset from each other. The terminals are cut in stages according to the wear development degree of the brake pad. The terminals define energization routes to electro-magnetic coils at relays, and the broken line state of the terminal can be detected at the respective relay by detection of a break in its corresponding energization route. As a result, electro-magnetic switches work in response to the wear development degree, turning on predetermined indicator lamps of a display to inform a driver of the brake wear condition.

Claims

1. A brake pad wear indicator probe comprising;

a core element disposed near a tip of the probe, the core element having first and second diameter portions, said first diameter portion being larger than said second diameter portion; and

a plurality of U-shaped electric wire paths having a turn part extending toward said tip of the probe, the turn part of each of said plurality of U-shaped electric wire paths wrapped around one of said first diameter portion and said second diameter portion, said plurality of electric wire paths being different in a length measured between the turn part of each of said plurality of electric wire paths and said tip of the probe;

wherein said plurality of electric wire paths are engaged with a brake pad and wear together with the brake pad.

2. The brake pad wear indicator probe as claimed in claim 1, wherein a second distance from said second diameter portion to said tip of said probe is greater than a first distance from said first diameter portion to said tip of said probe.

3. The brake pad wear indicator probe as claimed in claim 1, further comprising a pad wear indicator display for signaling a broken line state of each of said plurality of U-shaped electric wire paths of said probe.