SYSTEM FOR AUTOMATICALLY CHECKING BRAKE REGULATING SYSTEMS

• US 3,750,101 A
• Filed: 07/27/1971
• Issued: 07/31/1973
• Est. Priority Date: 07/27/1970
• Status: Expired due to Term

• Current Assignee: Gosta Holger Granlund
• Original Assignee: Gosta Holger Granlund
• Inventors: Granlund, Gosta Holger
• Primary Examiner(s): Waring, Alvin H.
• Application Number:
  US05/166,412
• Time in Patent Office: 735 Days
• Field of Search: 340/52R,52B,53 303/21R 188/181R,181C
• US Class Current: 340/453
• CPC Class Codes: B60T 2270/406 Test-mode; Self-diagnosis
• CPC Class Codes: B60T 8/885 using electrical circuitry

Abstract

This invention is related to a safety checking device for an electronic braking system used primarily in wheeled vehicles and which indicates a malfunction of the system before the braking system is applied. The safety device introduces a signal to an electronic unit in the braking system; if there is a failure thereof, a warning circuit is triggered to give a proper alarm to the vehicle operator. The safety device is also designed so that it does not operate during application of the braking system.

Claims

1. A system for checking the malfunction of a control system in combination therewith for an electronic brake control used for at least one wheel of a wheeled vehicle when the brakes are not applied comprising:

an output means;

a speed sensing means that transmits input signals which indicate changes in wheel speed;

a detector means operatively arranged with the sensing means so as to respond to the input signals and thereby transmit at predetermined reference levels control signals adapted to operate the output means;

a resistance circuit including a resistance connected to the deTector;

a pulse generator connected to an electrical system of the vehicle and capable of being activated and deactivated by an ignition switch of the vehicle for transmitting at certain intervals short pulses to the resistance circuit wherein in dependence on said pulses the resistance circuit is intermittently connected to ground thereby causing a voltage division and a reduction of the input signals to the detector so that in response thereto the detector transmits an output signal that the breaks are not applied;

an alarm circuit; and

a means detecting an absence of said output signal for triggering the alarm.

2. The arrangement according to claim 1, wherein the resistance circuit comprises:

a transistor that is arranged to be activated by said pulses to intermittently connect the resistance to ground so as to trigger simulated output signals from the detector.

3. A system for automatically checking for a malfunction in an electronic brake control used for at least one wheel of a wheeled vehicle when the brakes are not applied comprising:

a brake line output means connected to the wheel;

a speed sensing means that transmits input signals which indicate changes in wheel speed;

an electronic unit including a detector which detects and compares signals and operatively arranged with the speed sensing means so as to respond to the input signals and thereby transmit at predetermined reference levels control signals to control pressure in the output means, the improvement comprising;

a resistance circuit connected to the electronic unit including;

a resistor;

a pulse generator connected to an electrical system of the vehicle and capable of being activated and deactivated by an ignition switch of the vehicle for transmitting at certain intervals short pulses to the resistance circuit wherein in dependence on said pulses the resistance circuit is intermittently connected to ground, thereby causing a voltage division and a reduction of the input signals to the detector, so that the detector in response thereto transmits an output signal that the brakes are not applied;

an alarm circuit; and

a means detecting an absence of said output of signal for triggering the alarm.

4. A system according to claim 3, wherein the resistance circuit comprises:

a transistor that is arranged to be activated by said pulses to connect the resistance to ground so as to trigger simulated output signals from the detector.

5. A system according to claim 3, wherein the alarm circuit includes a transistor or like gating element which is controlled by the detecting means in cooperation and which is excited only by the presence of output signals from all the detectors in the electronic unit representing non-applied brakes, thereby connecting to earth a line passing from the pulse generator to alarm triggering means embodied in the alarm circuit.

6. A system according to claim 5, wherein the alarm triggering means includes a warning lamp controlled by a transistor or like electronic component acting as a power stage and having a base voltage which is regulated by the changed state of a capacitor which is supplied, via a blocking diode, with pulses from the pulse generator when the transistor controlled by the detecting diodes is switched off.