Positional feedback system for medical mattress systems

• US 6,353,950 B1
• Filed: 07/12/1996
• Issued: 03/12/2002
• Est. Priority Date: 05/09/1994
• Status: Expired due to Fees

• Current Assignee: Huntleigh Technology, Inc.
• Original Assignee: Kinetic Concepts Incorporated (3M Company)
• Inventors: Ohman, Randall, Bartlett, Alan L.
• Primary Examiner(s): TRETTEL, MICHAEL
• Application Number:
  US08/679,135
• Time in Patent Office: 2,069 Days
• Field of Search: 560/7, 560/9, 561/5, 561/7, 542/4, 571/0, 571/1, 571/3, 571/4, 571/5, 591/4
• US Class Current: 5/617
• CPC Class Codes: A61G 2203/36 for motion
• CPC Class Codes: A61G 2203/42 for inclination
• CPC Class Codes: A61G 2203/46 for temperature
• CPC Class Codes: A61G 7/001 with means for turning-over the patient
• CPC Class Codes: A61G 7/0525 Side-bolsters rests specially adapted for beds A61G7/065; non-medical devices for prevention against falling-out A47C21/08
• CPC Class Codes: A61G 7/05769 with inflatable chambers
• CPC Class Codes: A61G 7/1021 Inflatable cushions

Abstract

An apparatus adjusts the pressures of a therapeutic mattress surface in accordance with the angular position of that surface. The apparatus comprises an angular position sensor and a rotation sensor which are housed together in an enclosure having a top surface in the form of a circular plate. The circular plate mounts either on the surface of the mattress or on the bottom of a bed frame supporting the mattress. The angular position and rotation sensors measure the horizontal plane referenced perpendicular to the direction of the force of gravity. The apparatus further comprises a controller blower valve assembly which processes data received from the angular position and rotation sensors to maintain, increase, or decrease the pressures within the mattress.

Claims

1. An apparatus for measuring the angular position of a patient support surface relative to gravity force, comprising:

a patient support;

an angle sensor mounted to said patient support and having an output responsive to changes in said angle sensor'"'"'s position relative to gravity force; and

said angle sensor comprising circuitry for relating the output therefrom to the change in angular position of said patient support from horizontal to provide a measurement of the angular position of said patient support.

2. The apparatus according to claim 1, said angle sensor comprising;

an enclosure to house said angle sensor;

an inclinometer having output which changes responsively to said inclinometer'"'"'s positional changes relative to gravitational forces acting thereupon.

3. The apparatus according to claim 1, comprising:

multiple angle sensors having outputs which change responsively to said angle sensor'"'"'s positional changes relative to gravitational forces acting thereupon; and

one or multiple enclosures to house said angle sensors.

4. The apparatus according to claim 3 wherein said angle sensors comprise inclinometers having resistive outputs responsive to positional changes.

5. The apparatus according to claim 4 further comprising:

electrical current sources connected to said inclinometers to convert said inclinometers'"'"' outputs to voltages.

6. The apparatus according to claim 1 further comprising:

a second angle sensor mounted to said patient support and having an output responsive to changes in said angle sensor'"'"'s position relative to gravity force; and

circuitry for relating the output therefrom to the change in the angular position of said patient support from horizontal to provide a measurement of the tilt angle of said patient support.

7. The apparatus according to claim 6 wherein said second angle sensor is mounted to said patient support at an angle of approximately 90°

relative to said first angle sensor.

8. The apparatus according to claim 7 wherein said patient support surface comprises an inflatable patient support and circuitry responsive to the measurements of angular position and tilt angle for changing the pressure in said inflatable patient support.

9. The apparatus of claim 8 wherein said patient support surface comprises an inflatable patient support surface comprised of multiple sections for supporting respective portions of the body of a patient and circuitry for changing the pressure in each of said sections in response to the measurements of angular position and tilt angle.

10. Apparatus for supporting a patient comprising:

an inflatable patient support comprised of a plurality of separately inflated sections for supporting respective sections of the body of a patient at a desired pressure;

a source for inflating each of the sections of said inflatable patient support to the desired pressure;

an angle sensor mounted to said inflatable patient support and having an output responsive to changes in the position of said inflatable patient support relative to gravity force; and

circuitry for changing the pressure in each of the sections of said inflatable patient support in response to the output of said angle sensor as said inflatable patient support rotates from a horizontal to an angular position relative to horizontal.

11. The apparatus for supporting a patient according to claim 10 wherein said angle sensor comprises an inclinometer having a resistive output responsive to positional changes.

12. The apparatus for supporting a patient according to claim 10 wherein said angle sensor is mounted to a planar flange, the planar flange being oriented in a plane which is substantially parallel to the plane on which the patient is supported by said inflatable patient support.

13. The apparatus for supporting a patient according to claim 12 further comprising:

a second angle sensor mounted to said inflatable patient support and having an output responsive to changes in said angle sensor'"'"'s position relative to gravity force; and

circuitry for relating the output therefrom to the change in the angular position of said patient support from horizontal to provide a measurement of the tilt angle of said inflatable patient support along the longitudinal axis of said inflatable patient support.

14. The apparatus for supporting a patient according to claim 13 wherein said second angle sensor is mounted to said inflatable patient support surface at an angle of approximately 90°

to said planar flange.

15. The apparatus for supporting a patient according to claim 13 wherein said first and second angle sensors are mounted to a circuit board which is mounted to said planar flange, said circuit board having a bend therein at a point between said first and second angle sensors.

16. The apparatus for supporting a patient according to claim 13 additionally comprising first and second inflatable bladders positioned under said inflatable patient support surface and along the entire length thereof and inflated by said source to desired pressures in response to the output of said circuitry comprising said second angle sensor.

17. A patient support system comprising:

a patient support comprised of multiple sections, each section being adapted for supporting a respective section of the body of a patient;

a first angle sensor mounted to said patient support and having an output responsive to changes in the position of said first angle sensor relative to gravity force;

a second angle sensor mounted to said patient support an angle of approximately 90°

relative to said first angle sensor and having an output responsive to changes in the position of said second angle sensor relative to gravity force; and

circuitry for relating the outputs of said first and second angle sensors to the change in the position of the patient support surface relative to horizontal and providing outputs measuring any such changes.

18. The apparatus according to claim 17 wherein said first and second angle sensors are mounted to a circuit board having the bend of approximately 90°

therein at a point between said first and second angle sensors.

19. The apparatus according to claim 17 wherein said first and second angle sensors comprise inclinometers having resistive outputs responsive to positional changes.

20. The apparatus according to claim 17 further comprising:

a display responsive to said circuitry for providing outputs measuring the changes in the position of the patient support surface relative to horizontal.