US4520661A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Temperature and wear sensor for a brake
Assignee: Akebono Brake Industry Co Ltd
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Filing: 1983-05-24
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Granted: 1985-06-04
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Expires: 2003-05-24
Abstract
Abstract A temperature and wear sensor for a brake is fixed disposed in a brake cylinder, and the sensor has a slider to be pressed on the side face of a piston of the brake cylinder and a temperature sensing device; thereby wear out of brake lining and overheating of the brake fluid are detected through a pair of lead out wires, and the sensor can be used permanently.
Inventors
- 👤 Takashi Tamai
- 👤 Shigefumi Tomiyama
- 👤 Nobumasa Ohshima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 19:14
CPC Classifications
F; F16; F16D; F16D66/00; F16D66/02; F16D66/021; F16D66/022; F16D66/025; F16D2066/001
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
76 words
A temperature and wear sensor for a brake having a shoe movable by a piston and cylinder against a rotating part comprising: a composite position and temperature sensing device engageable between the cylinder and the piston, said device including: means for detecting and electrically indicating predetermined changes in temperature; and means including switch means operable by a predetermined relative position between the cylinder and the piston for electrically indicating a predetermined wear condition of the shoe.
Claim 2
Dependent Claim
76 words
A temperature and wear sensor for a brake having a shoe movable by a piston and cylinder against a rotating part comprising: a composite position and temperature sensing device engageable between the cylinder and the piston, said device including: means for detecting and electrically indicating predetermined changes in temperature; and means including switch means operable by a predetermined relative position between the cylinder and the piston for electrically indicating a predetermined wear condition of the shoe.
Claim 3
Dependent Claim
23 words
The sensor defined in claim 1 wherein the switch means includes: a movable slider; and means for urging said slider against the piston.
Claim 4
Dependent Claim
44 words
The sensor defined in claim 2 in which: the switch means includes a pair of normally-open contacts carried by the slider and adapted to be closed on attainment of the predetermined relative position, and the temperature change connecting means is connected across said contacts.
Claim 5
Dependent Claim
33 words
The sensor defined in claim 3 including: a sensor case, and wherein the contacts are disposed within said case and the slider has a rod-shaped part projecting through a hole in said case.
Claim 6
Dependent Claim
19 words
The sensor defined in claim 4 including: seal means between the part and the peripheral edge of the hole.
Claim 7
Dependent Claim
20 words
The sensor defined in claim 4 wherein the case is adapted to be filled with brake fluid from the cylinder.
Claim 8
Dependent Claim
39 words
The sensor defined in claim 1 wherein the switch means includes: a pair of electrical contacts; and means for urging said contacts against the piston, the temperature change detecting means being connected in series with one of said contacts.
Claim 9
Dependent Claim
45 words
The sensor defined in claim 1 wherein the switch means includes: a pair of normally-open contacts, one engageable by the piston and moved into contact with the other on attainment of the predetermined relative position; the temperature change connecting means being connected across said contacts.
Claim 10
Dependent Claim
18 words
The sensor defined in any one of claims 1-6 wherein the temperature change detecting means is a thermistor.
Claim 11
Dependent Claim
21 words
The sensor defined in any one of claims 1-6 wherein the temperature change detecting means is a platinum temperature measuring resistor.
Claim 12
Dependent Claim
18 words
The sensor defined in any one of claims 1-6 wherein the temperature change detecting means is a thermocouple.
Claim 13
Dependent Claim
19 words
The sensor defined in any one of claims 1-6 wherein the temperature change detecting means is a bi-metal switch.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-06-03 | 1988-12-03 | 1989-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-06-03 | 1992-12-03 | 1993-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-06-03 | 1996-12-03 | 1997-06-04 | $7700.00 | Window Closed / Lapsed |