US4062224A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Brake tester
Assignee: NUCLEUS CORP
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Filing: 1976-06-28
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Granted: 1977-12-13
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Expires: 1996-06-28
Abstract
Abstract Apparatus for the determination of the brake actuation and release time for pneumatic brake systems. The brake tester is pneumatically connected to both an external source of pressure and the vehicle reservoir with a solenoid valve disposed between the external source and the vehicle reservoir so that an operator may incrementally increase the pressure within the reservoir. The brake tester includes a timing circuit which begins to run upon movement of the vehicle brake pedal and stops upon the attainment of predetermined pressure value within the vehicle brake chambers. The timing circuit also includes memory means to store the results of the brake actuation test so that both a brake actuation and release test may be sequentially conducted without interruption.
Inventors
- 👤 Leo Z. Zeleney
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 14:22
CPC Classifications
G; G01; G01L; G01L5/00; G01L5/28; G01L5/284
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
271 words
A brake tester for a vehicle having a fluid brake system, said system having a reservoir which fluidly communicates with a vehicle brake chamber upon actuation of a vehicle brake pedal, said brake tester comprising, a housing, valve means contained within said housing for controlling the fluid pressure within said reservoir, a pressure transducer operatively coupled with said brake chamber and adapted to generate an analog electrical output signal representative of the fluid pressure within the brake chamber, and circuit means for measuring the elapsed time between the depression of the brake pedal and the attainment of a first pressure within said brake chamber and for measuring the elapsed time between the subsequent release of the brake pedal and the attainment of a second pressure within said brake chamber, said second pressure being lower than said first pressure, said circuit means comprising: accelerometer means attached to the brake pedal which emits an output signal in response to movement of the brake pedal, an analog signal processor having an input coupled to the analog output signal from said pressure transducer wherein said signal processor generates a first timing signal upon the depression of said brake pedal and the attainment of said first pressure in said brake chamber and wherein said signal processor generates a second timing signal upon the release of said brake pedal and the attainment of said second pressure in said brake chamber, first timing means started by the signal from said accelerometer means and stopped by said first timing signal, and second timing means started by the signal from said accelerometer means and stopped by said second timing signal.
Claim 2
Dependent Claim
271 words
A brake tester for a vehicle having a fluid brake system, said system having a reservoir which fluidly communicates with a vehicle brake chamber upon actuation of a vehicle brake pedal, said brake tester comprising, a housing, valve means contained within said housing for controlling the fluid pressure within said reservoir, a pressure transducer operatively coupled with said brake chamber and adapted to generate an analog electrical output signal representative of the fluid pressure within the brake chamber, and circuit means for measuring the elapsed time between the depression of the brake pedal and the attainment of a first pressure within said brake chamber and for measuring the elapsed time between the subsequent release of the brake pedal and the attainment of a second pressure within said brake chamber, said second pressure being lower than said first pressure, said circuit means comprising: accelerometer means attached to the brake pedal which emits an output signal in response to movement of the brake pedal, an analog signal processor having an input coupled to the analog output signal from said pressure transducer wherein said signal processor generates a first timing signal upon the depression of said brake pedal and the attainment of said first pressure in said brake chamber and wherein said signal processor generates a second timing signal upon the release of said brake pedal and the attainment of said second pressure in said brake chamber, first timing means started by the signal from said accelerometer means and stopped by said first timing signal, and second timing means started by the signal from said accelerometer means and stopped by said second timing signal.
Claim 3
Dependent Claim
81 words
The invention as defined in claim 1 wherein said valve means further comprises, a valve means contained in said housing, a first conduit connected at one end to said valve and at its other end to a source of external fluid pressure, and a second conduit connected at one end to said valve and at its other end to said reservoir, wherein said valve means is operable upon actuation to permit fluid communication from said first conduit to said second conduit.
Claim 4
Dependent Claim
24 words
The invention as defined in claim 2 and including a pressure gage secured in said housing and in fluid communication with said second conduit.
Claim 5
Dependent Claim
15 words
The invention as defined in claim 2 wherein said valve is an electric solenoid valve.
Claim 6
Dependent Claim
25 words
The invention as defined in claim 1 and including memory means for storing the results of said first timing means and said second timing means.
Claim 7
Dependent Claim
110 words
The invention as defined in claim 1 wherein said first timing means comprises a counter and a free running clock selectively gated into said counter upon the signal from the accelerometer means, and a latch having its inputs connected to the outputs of said counter and adapted to store the count from the counter upon the first timing signal from the analog signal processor, and wherein said second timing means comprises means to reset the counter after the first timing signal, means to stop the counter upon the second timing signal from the analog signal processor, and means to selectively display the results stored in the latch and the counter.
Claim 8
Dependent Claim
57 words
The invention as defined in claim 7 wherein said latch is tri-state latch and said last mentioned means further comprises a tri-state transmission gate having its inputs connected to the counter outputs and its outputs connected to both the display means and the latch outputs and control means to alternatively activate the transmission gate or the latch.
Claim 9
Dependent Claim
154 words
The invention as defined in claim 6 wherein said analog processor further comprises a voltage comparator having one input coupled to said pressure transducer, a voltage divider having at least a first and a second output means for connecting one of said voltage divider outputs to the other input of said voltage comparator, wherein said first voltage divider output corresponds to the output signal from said pressure transducer when the pressure in the brake chamber substantially equals said first pressure and wherein said second voltage divider output corresponds to the output signal from the pressure transducer when the fluid pressure in the brake chamber substantially equals said second pressure, circuit means for generating an output pulse of a preselected polarity when the voltage level from the pressure transducer output exceeds the connected first voltage divider output and when the voltage level from the pressure transducer output falls below the connected second voltage divider output.
Claim 10
Dependent Claim
46 words
The invention as defined in claim 1 wherein said housing is dimensioned to fit within the cab of said vehicle so that a single operator can control said valve means and circuit means within said housing and also control the actuation of said vehicle brake pedal.
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) | 1980-12-12 | 1981-06-13 | 1981-12-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-12-12 | 1985-06-13 | 1985-12-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-12-12 | 1989-06-13 | 1989-12-13 | $7700.00 | Window Closed / Lapsed |