CONSTANT LOW-FLOW AIR SOURCE CONTROL SYSTEM AND METHOD
First Claim
1. A person-support apparatus comprisingan inflatable support structure,a variable output pump in fluid communication with the inflatable support structure, wherein the variable output pump provides a flow of fluid to the inflatable support structure,a controller coupled to the variable output pump, the controller including means for dynamically varying the output of the pump to maintain an output pressure of the pump to a value slightly higher than the pressure in the inflatable support structure during the inflation process to maintain a constant flow from the pump.
7 Assignments
0 Petitions
Accused Products
Abstract
A constant low-flow air source control system and method is used to operate a pump to inflate an inflatable support structure used to support a person.
45 Citations
20 Claims
-
1. A person-support apparatus comprising
an inflatable support structure, a variable output pump in fluid communication with the inflatable support structure, wherein the variable output pump provides a flow of fluid to the inflatable support structure, a controller coupled to the variable output pump, the controller including means for dynamically varying the output of the pump to maintain an output pressure of the pump to a value slightly higher than the pressure in the inflatable support structure during the inflation process to maintain a constant flow from the pump.
-
9. A person support apparatus comprising
an inflatable support structure, a variable output pump including a driver responsive to a drive signal, the variable output pump in fluid communication with the inflatable support structure to transfer fluid to the inflatable support, a control system including a processor, a sensor in communication with the processor, the sensor operable to detect the pressure in the inflatable support structure and transmit a pressure signal to the processor indicative of the pressure in the inflatable structure, a drive circuit in electrical communication with the processor and the driver of the variable output pump, the drive circuit configured to form a drive signal for the driver, wherein the processor processes the pressure signal to determine an optimum operating condition and operates the drive circuit to vary the drive signal to cause the pump to transfer fluid to the inflatable support at a substantially constant flow irrespective of the current pressure in the inflatable support structure.
-
17. A method of controlling a variable output pump for inflating an inflatable support structure for a person support apparatus comprising the steps of:
-
operating the pump at a maximum output for a period of time to inflate the inflatable support structure to a target pressure; measuring the pressure in the inflatable support structure; and varying the drive rate of the pump based on changes in the pressure in the inflatable support structure over time to maintain the mass flow rate from the pump to the inflatable support structure a generally constant level over time to maintain the pressure in the inflatable support structure at a value that is substantially the same as the target pressure. - View Dependent Claims (18, 19, 20)
-
Specification