Control system for fluid-filled beds
AssigneeAngel Echevarria Co., Inc.
InventorDerek P. Dotson
Life of this patent
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Abstract
A system for automatically controlling the pressure maintained in a plurality of fluid-filled cylinders supporting a sleep surface in order to maintain a desired degree of firmness/softness. In one mode, the system permits the user to set the desired level of firmness and then the system acts to maintain that level under the conditions encountered in use, either venting if an above-setting pressure is sensed or pumping to fill if a below-setting pressure is detected. In another mode, the user is enabled to manually activate either the pump or the vent in order to vary the firmness to his choice.
Claims21
A control system for a fluid-filled bed comprising:
- a plurality of containers for receiving fluid from a pressurized source, said containers being arranged to support a fluid flotation sleep surface;
- means coupling said containers to a common plenum chamber;
- a sensor for monitoring the pressure of fluid in said chamber;
- a pump for supplying fluid to said chamber;
- a valve for venting fluid from said chamber;
- a selector device for setting a chosen level of firmness corresponding to pressure within said containers and chamber;
- and
- control means for comparing pressure signals from said sensor with said chosen firmness setting and selectively activating said pump and said venting valve upon detection of a difference between said pressure signals and said setting which exceeds a predetermined threshold value where said threshold value is greater than zero.
The method of controlling the pressure of fluid in a fluid-filled bed, which bed comprises a plurality of fluid containers coupled for communication with a common plenum chamber, a sensor for monitoring the pressure of fluid in said chamber, a pump for supplying fluid to said chamber, a valve for venting fluid from said chamber, and a selector device for setting a chosen level of firmness corresponding to pressure within said containers and chamber, said method comprising the steps of:
- (a) comparing the pressure in said chamber with the preset firmness level to determine the existence of a difference which exceeds a predetermined threshold value, said threshold value being greater than zero;
- (b) activating the venting valve for a predetermined reference interval of time in the event said sensed pressure is higher than the preset firmness level by more than said threshold value;
- (c) noting the chamber pressures at the beginning and end of said reference interval;
- (d) calculating a vent interval which is required to reduce the chamber pressure to said preset firmness level, based on the pressure change detected during said reference interval;
- and
- (e) activating the venting valve for said calculated vent interval.
Dependencies are inferred from the claim text.