Foam additive supply system for rescue and fire fighting vehicles

• US 6,725,940 B1
• Filed: 05/10/2000
• Issued: 04/27/2004
• Est. Priority Date: 05/10/2000
• Status: Expired due to Term

• Current Assignee: Pierce Manufacturing Incorporated (Oshkosh Corporation)
• Original Assignee: Pierce Manufacturing Incorporated (Oshkosh Corporation)
• Inventors: Bolen, Kenneth A. Jr., High, Thomas A., Piller, Brian D., Klein, Andrew P., Grady, Clarence A.
• Primary Examiner(s): Ganey, Steven J.
• Application Number:
  US09/567,604
• Time in Patent Office: 1,448 Days
• Field of Search: 169/13, 169/14, 169/15, 169/24, 239/67, 239/68, 239/69, 239/310, 239/318, 239/172, 417/43, 417/46
• US Class Current: 169/15
• CPC Class Codes: A62C 27/00 Fire-fighting land vehicles
• CPC Class Codes: A62C 31/12 for delivering foam or atomised foam
• CPC Class Codes: A62C 5/02 of foam
• CPC Class Codes: A62C 99/0036 using foam

Abstract

A system for supplying a pre-determined ratio of liquid foam concentrate and water to a mixing device immediately upstream from a fire fighting nozzle. The system is electronically balanced by measuring pressure from a plurality of pressure signal sensors and transmitting said pressure signals to a controller unit. A foam additive pump is powered by a fixed displacement piston motor which in turn is electronically modulated independently of the level of operation of the water pump by a control system that is responsive both to the water pressure developed by the water pump and to the foam liquid concentrate pressure developed by the additive pump.

Claims

1. An additive supply system for fire fighting mechanisms, the additive system comprising:

a means for supplying pressurized water to a mixing device;

a means for supplying pressurized additive to the mixing device for mixing with the pressurized water;

a pressure transducer for measuring the pressure of the pressurized water prior to mixing with the pressurized additive, said pressure transducer being fluidly coupled to the means for supplying pressurized water;

a means for measuring the pressure of the pressurized additive prior to mixing with the pressurized water, said means for measuring the pressure of the pressurized additive fluidly coupled to the means for supplying pressurized additive; and

a means for controlling an output of the means for supplying pressurized additive to the mixing device in response to both the pressure of the pressurized water and the pressure of the pressurized additive, said means for controlling the output electronically coupled to said pressure transducer and said means for measuring the pressure of the pressurized additive.

2. An additive supply system according to claim 1, wherein the means for controlling the output of the means for supplying pressurized additive to the mixing device in response to both the pressure of the pressurized water and the pressure of the pressurized additive is digital electronic.

3. An additive supply system according to claim 1, the additive supply system further comprising, a means for adjusting the speed of an additive pump by varying the displacement of a hydraulic pump fluidly coupled to the additive pump by adjusting a swash plate in the hydraulic pump, the means for adjusting the speed of an additive pump controlling the output of the means for supplying pressurized additive to the fluid/additive mixing device in response to both the pressure of the pressurized water and the pressure of the pressurized additive.

4. An additive supply system according to claim 3, wherein the means for adjusting the speed of an additive pump is a swash plate in the hydraulic pump adjusted by a pressure compensator in the hydraulic pump that responds to a hydraulic pressure signal sent from a proportional relief valve.

5. A vehicle carrying an additive supply system according to claim 1.

6. An additive supply system for fire fighting mechanisms, the additive system comprising:

a means for-supplying pressurized water to a mixing device;

a means for supplying pressurized additive to the mixing device for mixing with the pressurized water;

a means for measuring the pressure of the pressurized water prior to mixing with the pressurized additive, said means for measuring the pressure of the pressurized water fluidly coupled to the means for supplying pressurized water;

a pressure transducer for measuring the pressure of the pressurized additive prior to mixing with the pressurized water, said pressure transducer being fluidly coupled to the means for supplying pressurized additive; and

a means for controlling an output of the means for supplying pressurized additive to the mixing device in response to both the pressure of the pressurized water and the pressure of the pressurized additive, said means for controlling the output electronically coupled to said means for measuring the pressure of the pressurized water and said pressure transducer.

7. An additive supply system according to claim 6, wherein the means for controlling the output of the means for supplying pressurized additive to the mixing device in response to both the pressure of the pressurized water and the pressure of the pressurized additive is digital electronic.

8. An additive supply system according to claim 6, the additive supply system further comprising, a means for adjusting the speed of an additive pump by varying the displacement of a hydraulic pump fluidly coupled to the additive pump by adjusting a swash plate in the hydraulic pump, the means for adjusting the speed of an additive pump controlling the output of the means for supplying pressurized additive to the fluid/additive mixing device in response to both the pressure of the pressurized water and the pressure of the pressurized additive.

9. An additive supply system according to claim 8, wherein the means for adjusting the speed of an additive pump is a swash plate in the hydraulic pump adjusted by a pressure compensator in the hydraulic pump that responds to a hydraulic pressure signal sent from a proportional relief valve.

10. A vehicle carrying an additive supply system according to claim 6.