Claims
- 1. A safety system for applying an air parking brake on a vehicle, the system comprising:a solenoid valve in an air line supplying air to a parking brake, the solenoid valve being upstream of the parking brake, the solenoid valve comprising a blocking valve positioned to block the air line and a vent positioned to vent air pressure from the air line downstream of the solenoid valve; a controller operatively linked to the solenoid valve, the controller comprising a plurality of station circuits, each station circuit including a switch that is opened when a condition exists in which vehicle movement would be dangerous, and in which the controller actuates the solenoid valve to block the air line and vent the air line when any one of the switches is opened.
- 2. A safety system as in claim 1, wherein one of said plurality of station circuits includes a vehicle ignition switch.
- 3. A safety system as in claim 1, wherein one of said plurality of station circuits includes a vehicle door switch that is open when the door is open and closed when the door is closed.
- 4. A safety system as in claim 1, wherein one of said plurality of station circuits includes a switch positioned at or near a wheelchair lift on the vehicle.
- 5. A safety system as in claim 1, wherein the controller comprises a vehicle motion override, wherein the controller will not apply the parking brake if the vehicle is in motion.
- 6. A safety system as in claim 1, further comprising a loading valve and an air pressure supply, wherein the solenoid valve is between the loading valve and the air pressure supply.
- 7. A safety system as in claim 1, further comprising a loading valve and an air pressure supply, wherein the solenoid valve is between the loading valve and the air brake.
- 8. A safety system as in claim 1 further comprising an air pressure supply, wherein the solenoid valve is between the air pressure supply and the air brake, and the system comprises no other valves in the air line between the air pressure supply and the air brake.
- 9. A safety system as in claim 1 further comprising an air pressure supply, wherein the solenoid valve is between the air pressure supply and the air brake, and the system comprises a two-way check valve between the solenoid valve and the air system.
DESCRIPTION
This application is a continuation-in-part of prior, co-pending application Ser. No. 09/108,863, filed Jul. 1, 1998, and entitled “Automatic Air Parking Brake Lock,” which application is herein incorporated by reference.
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DE |
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GB |
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Entry |
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Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
09/108863 |
Jul 1998 |
US |
Child |
09/521824 |
|
US |