Body support with adaptive pressurization

• US 5,687,099 A
• Filed: 02/06/1995
• Issued: 11/11/1997
• Est. Priority Date: 02/06/1995
• Status: Expired due to Fees

• Current Assignee: Bcam International, Inc. (CellMetrix, Inc.)
• Original Assignee: Bcam International, Inc. (CellMetrix, Inc.)
• Inventors: Cassar, Thomas J., Gross, Clifford M., Lu, Cindy Hongzheng
• Primary Examiner(s): Trammell, James P.
• Application Number:
  US08/384,103
• Time in Patent Office: 1,009 Days
• Field of Search: 364/558, 5/616, 36/29, 297/284.1-284.11
• US Class Current: 702/98
• CPC Class Codes: A47C 27/083 with pressure control, e.g. with pressure sensors
• CPC Class Codes: A47C 27/10 with two or more independently-fillable chambers
• CPC Class Codes: A61G 2203/34 for pressure
• CPC Class Codes: A61G 5/1043 Cushions specially adapted for wheelchairs
• CPC Class Codes: A61G 5/1045 for the seat portion
• CPC Class Codes: A61G 7/05776 with at least two groups of alternately inflated chambers

Abstract

An apparatus for supporting a body portion in a preferred embodiment has a plurality n of inflatable members M_i (i=1, . . . , n) in a desired configuration. Each member is individually adjustable to a desired pressure from a pressure source. The apparatus also has a pressure-sensing arrangement for sensing the pressure in each of the members M_i. Furthermore the apparatus has a control arrangement for adjusting the pressure in the members M_i according to a protocol. The protocol includes the steps of

(i) initially inflating each member M_i until a predetermined condition has been achieved;

(ii) determining the pressure P_Oj (j=i) of each member M_i resulting after initial inflation;

(iii) determining the desired pressure P_Di of each member M_i as a function F_i of the pressures P_Oj (j=1, . . . n) obtained in step (ii), such that P_Di =F_i (P₀₁, . . . , P_Dn); and

(iv) adjusting the pressure of each member M_i to a final pressure P_Fi that matches the desired pressure determined for such member in step (iii), such that P_Fi =P_Di =F_i (P₀₁, . . . , P_Dn).

Claims

1. An apparatus for supporting a body portion of a person, the apparatus comprising:

(a) a plurality n of inflatable members M_i (i=1, . . . , n) in a desired configuration, each member being individually adjustable to a desired pressure from a pressure source;

(b) a pressure-sensing arrangement for sensing the pressure in each of the members M_i ;

(c) a control arrangement for adjusting the pressure in the members M_i according to a protocol, wherein the protocol includes;

(i) initially inflating each member M_i until a predetermined condition has been achieved;

(ii) determining the pressure P_Oj (j=i) of each member M_i resulting after initial inflation;

(iii) determining the desired pressure P_Di of each member M_i as a function F_i of the pressures P_Oj (j=1, . . . n) obtained in step (ii), such that P_Di =F_i (P₀₁, . . . , P_0n ; and

(iv) adjusting the pressure of each member M_i to a final pressure P_Fi that matches the desired pressure determined for such member in step (iii), such that P_Fi =P_Di =F_i (P₀₁, . . . , P_0n).

2. An apparatus according to claim 1, wherein the predetermined condition is the elapsing of a specified time interval.

3. An apparatus according to claim 1, wherein:

step (c) (ii) of the protocol is performed after the body portion is on the apparatus; and

each function F_i of the pressures P_Oj includes the weighted sum of the pressures P_Oj, so that the desired pressures P_Di of the members M_i reflect the total effective weight of the body portion.

4. An apparatus according to claim 3, wherein the function F_i of the pressures P_Oj includes the simple sum of the pressures P_Oj.

5. An apparatus according to claim 3, wherein each function F_i is constructed to produce a desired pressure P_Di in the member M_i so as to cause a desired fraction of the load of the body portion to be borne by the member M_i, and the collection of functions F_i thus causes the load of the body portion to have a desired distribution over the members M_i.

6. An apparatus according to claim 5, wherein the desired pressure P_Di in the member M_i is a monotonic increasing function of the weighted sum of the pressures P_Oj, so that a heavier body portion may be supported by greater pressures in each member M_i.

7. An apparatus according to claim 6, wherein the pressures in the pressure sets P_Oj and P_Fi are determined on a time-averaged basis.

8. An apparatus according to claim 3, wherein at least steps (c) (iii) and (c) (iv) of the protocol are performed on a repetitive basis.

9. An apparatus according to claim 8, wherein:

each function F_i is constructed to produce a desired pressure P_Di in the member M_i tending to cause a desired fraction of the load of the body portion to be borne by the member M_i, and the collection of functions F_i tends to cause the load of the body portion to have a desired distribution over the members M_i ; and

the function F_i for at least two of the members M_i is altered in successive repetitions of the protocol, so as to produce a massage effect.

10. An apparatus according to claim 8, further comprising:

an event-specific trigger for repetition of the protocol.

11. An apparatus according to claim 10, wherein the event-specific trigger is a user-actuated comfort switch.

12. An apparatus according to claim 10, wherein the event-specific trigger is a body-present sensor.

13. An apparatus according to claim 10, wherein the event-specific trigger is a timer.

14. An apparatus according to claim 10, wherein the event-specific trigger is a body-activity monitor.

15. An apparatus according to claim 1, wherein the pressures in at least one of the pressure sets P_Oj and P_Fi are determined on a time-averaged basis.

16. An apparatus according to claim 15, wherein the pressures in both of the pressure sets P_Oj and P_Fi are determined on a time-averaged basis.

17. An apparatus according to claim 1, further comprising:

means for modification by the user of at least one of the functions F_i to modify the firmness of the corresponding member(s).

18. A method for adjusting the pressures in an apparatus for supporting a body portion of a person, the apparatus comprising a plurality n of inflatable members M_i (i=1, . . . , n) in a desired configuration, each member being individually adjustable to a desired pressure from a pressure source, a pressure-sensing arrangement for sensing the pressure in each of the members M_i, and a control arrangement for adjusting the pressure in the members M_i according to a protocol;

the method comprising the steps of;

(a) determining an initial pressure P_Oj (j=i) of each member M_i ;

(b) determining the desired pressure P_Di of each member M_i as a function F_i of the pressures P_Oj (j=1, . . . n) such that P_Di =F_i (P₀₁, . . . , P_On); and

(c) adjusting the pressure of each member M_i to a final pressure P_Fi similar to the desired pressure, such that P_Fi =P_Di =F_i (P₀₁, . . . , P_On).

19. A method according claim 18, wherein the predetermined condition is the elapsing of a specified time interval.

20. A method according to claim 18, wherein:

step (a) is performed after the body portion is on the apparatus; and

each function F_i of the pressures P_Oj includes the weighted sum of the pressures P_Oj, so that the desired pressures P_Di of the members M_i reflect the total effective weight of the body portion.

21. A method according to claim 20, wherein the function F_i of the pressures P_Oj includes the simple sum of the pressures P_Oj.

22. A method according to claim 20, wherein the each function F_i is constructed to produce a desired pressure P_Di in the member M_i so as to cause a desired fraction of the load of the body portion to be borne by the member M_i, and the collection of functions F_i thus causes the load of the body portion to have a desired distribution over the members M_i.

23. A method according to claim 22, wherein the desired pressure P_Di in the member M_i is a monotonic increasing function of the weighted sum of the pressures P_Oj, so that a heavier body portion may be supported by greater pressures in each member M_i.

24. A method according to claim 20, wherein the pressures in the pressure sets P_Oj and P_Fi are determined on a time-averaged basis.

25. A method according to claim 20, wherein at least steps (b) and (c) are performed on a repetitive basis.

26. A method according to claim 25, wherein:

each function F_i is constructed to produce a desired pressure P_Di in the member M_i so as to cause a desired fraction of the load of the body portion to be borne by the member M_i, and the collection of functions F_i thus causes the load of the body portion to have a desired distribution over the members M_i ; and

the function F_i for at least two of the members M_i is altered in successive repetitions of steps (b) and (c), so as to produce a massage effect.

27. A method according to claim 25, wherein the repetition of steps (b) and (c) is triggered by a specific event.

28. A method according to claim 27, wherein the event is actuation of a user-actuated comfort switch.

29. A method according to claim 27, wherein the event is actuation by a body-present sensor.

30. A method according to claim 27, wherein the event is passage of a second specified time interval.

31. A method according to claim 27, wherein the event is actuation by a body-activity monitor.

32. A method according to claim 18, wherein the pressures in at least one of the pressure sets P_Oj and P_Fi are determined on a time-averaged basis.

33. A method according to claim 32, wherein the pressures in both of the pressure sets P_Oj and P_Fi are determined on a time-averaged basis.

34. A method according to claim 18 further comprising the step of:

(d) altering the pressure of at least two of the members M_i in successive repetitions so as to produce a massage effect.

35. The method according to claim 34, wherein at least one of steps (a), (b), (c) and (d) are performed on a repetitive basis.

36. An apparatus for supporting a body portion of a person, the apparatus comprising:

(a) a plurality n of inflatable members M_i (i=1, . . . , n) in a desired configuration, each member being individually adjustable to a desired pressure from a pressure source;

(b) a sensing arrangement for sensing comfort as a function of the pressure in each of the members M_i ;

(c) a control arrangement for adjusting the pressure in the members M_i according to a protocol, wherein the protocol includes;

(i) initially inflating each member M_i until a predetermined condition has been achieved;

(ii) determining an initial comfort value by first measuring the pressure P_Oj (j=i) of each member M_i resulting after initial inflation and then calculating the comfort value from the pressures P_Oj ;

(iii) determining a desired comfort value and an associated desired pressure P_Di for each member M_i, the desired pressure P_Di needed to achieve the desired comfort value; and

(iv) adjusting the pressure of each member M_i to a final pressure P_Fi that matches the desired pressure determined for such member in step (iii), so that the desired comfort value is achieved.

37. An apparatus according to claim 36, wherein the pressures in at least one of the pressure sets P_Oj and P_Fi are determined on a time-averaged basis.

38. An apparatus according to claim 37, wherein the pressures in both of the pressure sets P_Oj and P_Fi are determined on a time-averaged basis.

39. An apparatus according to claim 36, wherein at least steps (iii) and (iv) of the protocol are performed on a repetitive basis.

40. An apparatus according to claim 39, wherein step (iv) of the protocol is not performed unless a difference between a previous desired comfort value and a new desired comfort value measured in step (iii) is below a predetermined minimum threshold value or above a predetermined maximum threshold value.