Reinforced and adjustable contoured seat cushion and method of reinforcing and adjusting the contoured seat cushion

• US 7,140,057 B2
• Filed: 01/28/2004
• Issued: 11/28/2006
• Est. Priority Date: 07/28/2003
• Status: Expired due to Term

• Current Assignee: Sunrise Medical Us LLC (Sunrise Medical Incorporated)
• Original Assignee: Aspen Seating LLC
• Inventors: Hetzel, Thomas R., Maurus, Steve, Pierce, Aaron D.
• Primary Examiner(s): Safavi, Michael
• Application Number:
  US10/766,623
• Publication Number:
  US 20050022306A1
• Time in Patent Office: 1,035 Days
• Field of Search: 297/452.23, 297/452.26, 297/452.27, 297/452.28, 565/3, 565/4, 565/41, D65/02
• US Class Current: 5/653
• CPC Class Codes: A47C 7/029 of non-adjustable shape adapted to a user contour or ergonomic seating positions
• 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 7/05723 with cut-outs or depressions in order to relieve the pressure on a part of the body mattresses with cavities A47C27/142

Abstract

A flexible seat cushion, such as a wheelchair cushion, has an upper surface with a support contour for establishing relatively less pressure on skin adjacent to the bony prominences of the person'"'"'s pelvic area and relatively more pressure on skin covering adjacent tissue masses. A support member is attached to the rear corner of the cushion. The support member has relatively less flexibility than the seat cushion. The support member is retained to a longitudinal and/or transverse side of the cushion to cause the support member to resist deformation of the support contour from contact with the pelvic area of the person when seated on the seat cushion. Connector member may be connected to the support member to extend along longitudinal and/or transverse sides of the cushion to deform and thereby adjust the support contour for better support of the pelvic area.

Claims

1. A flexible seat cushion for supporting a person in a seated position thereon, having generally transversely spaced and longitudinally extending longitudinal sides and generally longitudinally spaced and transversely extending front and rear transverse sides, the longitudinal sides intersecting the rear side at rear corners and the longitudinal sides intersecting the front side at front corners, and an upper surface extending between the sides and defining a support contour for contacting and supporting a person in a sitting position, comprising;

a support contour, including relief areas at locations adjacent to skin covering at least one bony prominence of a pelvic area of the person seated on the cushion, and support areas adjacent to skin covering tissue masses adjacent to the one bony prominence, the relief areas and support areas positioned to establish relatively less pressure on the skin in the relief areas and relatively more pressure on the skin in the support areas, the relief areas including a center cavity generally transversely centered between the longitudinal sides and longitudinally spaced more toward the rear side than the front side;

a support member attached to a rear corner of the flexible seat cushion, the support member having relatively less flexibility than the seat cushion to resist deformation of the support contour from contact with the pelvic area of the person when seated on the seat cushion;

a connector member connected to the support member and extending along one of the longitudinal sides or the rear side which intersect at the rear corner, the connector member having a length that is adjustable to move the support member in a direction substantially parallel to one side along which the connector member extends, the connector member comprises a strap having first and second portions, the first portion of the strap is connected to the support member, the second portion of the strap is connected to the one side along which the connector member extends, the strap includes a fastener, and the first and second portions are interconnected by the fastener.

2. A seat cushion as defined in claim 1, wherein:

a functional length of the strap is adjustable.

3. A seat cushion as defined in claim 2, wherein:

the fastener connects the first and second portions at a plurality of selected positions to adjust the functional length of the strap.

4. A seat cushion as defined in claim 3, wherein:

the fastener comprises a buckle.

5. A seat cushion as defined in claim 4, wherein:

the buckle connects the first and the second portions of the strap; and

the buckle is fixed to one of the first or second portions of the strap, and the buckle holds the other one of the first or second portions of the strap to adjust the functional length of the strap.

6. A seat cushion as defined in claim 5, wherein:

the buckle holds the other one of the first or second portions by friction.

7. A flexible seat cushion for supporting a person in a seated position thereon, having generally transversely spaced and longitudinally extending longitudinal sides and generally longitudinally spaced and transversely extending front and rear transverse sides, the longitudinal sides intersecting the rear side at rear corners and the longitudinal sides intersecting the front side at front corners, and an upper surface extending between the sides and defining a support contour for contacting and supporting a person in a sitting position, comprising;

a support contour, including relief areas at locations adjacent to skin covering at least one bony prominence of a pelvic area of the person seated on the cushion, and support areas adjacent to skin covering tissue masses adjacent to the one bony prominence, the relief areas and support areas positioned to establish relatively less pressure on the skin in the relief areas and relatively more pressure on the skin in the support areas, the relief areas including a center cavity generally transversely centered between the longitudinal sides and longitudinally spaced more toward the rear side than the front side;

a support member attached to a rear corner of the flexible seat cushion, the support member having relatively less flexibility than the seat cushion to resist deformation of the support contour from contact with the pelvic area of the person when seated on the seat cushion;

a connector member connected to the support member and extending along one of the longitudinal sides or the rear side which intersect at the rear corner, the connector member having a length that is adjustable to move the support member in a direction substantially parallel to one side along which the connector member extends, the connector member comprises a strap having first and second portions, the first portion of the strap is connected to the support member, the second portion of the strap is connected at a position along the one side along which the connector member extends, and the position along the one side at which the second portion of the strap is connected is adjustable.

8. A seat cushion as defined in claim 7, wherein:

the second portion of the strap is connected in the position along the one side by a hook and loop fastener.

9. A flexible seat cushion for supporting a person in a seated position thereon, having generally transversely spaced and longitudinally extending longitudinal sides and generally longitudinally spaced and transversely extending front and rear transverse sides, the longitudinal sides intersecting the rear side at rear corners and the longitudinal sides intersecting the front side at front corners, and an upper surface extending between the sides and defining a support contour for contacting and supporting a person in a sitting position, comprising;

a support contour, including relief areas at locations adjacent to skin covering at least one bony prominence of a pelvic area of the person seated on the cushion, and support areas adjacent to skin covering tissue masses adjacent to the one bony prominence, the relief areas and support areas positioned to establish relatively less pressure on the skin in the relief areas and relatively more pressure on the skin in the support areas, the relief areas including a center cavity generally transversely centered between the longitudinal sides and longitudinally spaced more toward the rear side than the front side;

a support member attached to a rear corner of the flexible seat cushion, the support member having relatively less flexibility than the seat cushion to resist deformation of the support contour from contact with the pelvic area of the person when seated on the seat cushion;

a first connector member connected to the support member and extending along one longitudinal side; and

a second connector member connected to the support member and extending along the rear transverse side; and

the first and second connector members connect to the same support member at the rear corner adjacent to the center cavity.

10. A seat cushion as defined in claim 9, wherein:

the first and second connector members have functional lengths that are adjustable independently of one another to move the support member in a direction parallel to the extension of the longitudinal and rear transverse sides, respectively; and

adjustment of a functional length of either one of the connector members changes the shape of the support contour at the cavity where the support member is located.

11. A seat cushion as defined in claim 10, wherein the bony prominences of the pelvic area include ischial tuberosities and coccyx and sacrum, and wherein the seat cushion includes:

a back wall surrounding the rear pelvic area of the person, the back wall defining a portion of the center cavity of the support contour, the transversely extending rear side of the cushion including the back wall; and

wherein;

the center cavity is located directly below the ischial tuberosities of the person sitting when on the support contour, the cavity curving downwardly and longitudinally forwardly and transversely inwardly from the back wall to a generally horizontal lowermost surface area of the cavity, the lowermost surface area of the cavity is at a location vertically spaced below the ischial tuberosities and has longitudinal and transverse dimensions relative to the ischial tuberosities to establish the relatively less pressure on the skin covering the ischial tuberosities during movement within an anticipated range of forward, backward and side to side movement of an upper torso of the person sitting on the support contour, the lowermost surface area constituting one relief area of the support contour;

a channel area located directly behind the coccyx and sacrum of the person sitting on the support contour, the channel area extending downwardly and longitudinally forwardly from the back wall toward the lowermost surface area of the cavity at a transverse midline of the support contour, the channel area has dimensions extending longitudinally and transversely relative to the coccyx and sacrum to establish the relatively less pressure on the skin covering the coccyx and sacrum during an anticipated range of normal movement of the pelvic area of the person while sitting on the support contour, the channel area constituting a relief area;

at least one pelvic protrusion area located adjacent the skin covering the tissue masses at the opposite lateral posterior buttocks of the person sitting on the support contour, each pelvic protrusion area located at transversely oppositely spaced positions from the channel area, each pelvic protrusion area generally curving vertically downwardly and transversely and longitudinally inwardly from the back wall toward the lowermost surface area, each pelvic protrusion area terminating vertically above the lowermost surface area, each pelvic protrusion area defining a forwardly and upwardly facing contact surface to contact the skin covering the tissue masses at the lateral posterior buttocks, the forwardly and upwardly facing contact surfaces transferring force to the tissue masses at the opposite posterior buttocks to offload pressure from the skin covering the coccyx and sacrum while the person is sitting on the support contour, each pelvic protrusion area constituting a support area; and

wherein;

the contact surfaces of the protrusion areas extend forwardly into the cavity compared to the channel area; and

shortening a functional length of the second connector member moves the pelvic protrusion area adjacent to the support member relatively more transversely inward toward the pelvic area of the user.

12. A seat cushion as defined in claim 11, wherein the bony prominences of the pelvic area also include greater trochanters, and wherein the seat cushion further includes:

a lateral area on each opposite transverse side of the cavity and located transversely to the outside of and vertically below the greater trochanters of the person sitting on the support contour, each lateral area generally curving vertically downwardly and transversely inwardly from an outer periphery of the support contour to intersect transverse opposite sides of the cavity at a position above the ischial tuberosities of the person sitting on the support contour, the lateral areas also extending longitudinally relative to the greater trochanters of the person sitting on the support contour, the lateral areas having sufficient longitudinal, transverse and vertical dimensions to establish the relatively less pressure on the skin covering the greater trochanters during movement within an anticipated range of different contacting support positions of the person on the support contour, each lateral area constituting one relief area; and

a posterior thigh protrusion area located beneath the skin covering the tissue masses at the posterior thighs of the person sitting on the support contour, each posterior thigh protrusion area located on transversely oppositely sides of a longitudinal midline through the support contour, each posterior thigh protrusion area positioned vertically above and longitudinally forward of each lateral area, each posterior thigh protrusion area defining an upwardly facing fulcrum-like contact surface at a posterior position of the thigh leg bone, the posterior thigh protrusion areas have sufficient longitudinal, transverse and vertical dimensions to establish the relatively greater pressure on the skin covering the tissue masses at the posterior thighs, the fulcrum-like contact surfaces transferring force from the legs distal to the proximal thighs in a lever-like manner through the thigh bones to elevate the greater trochanters relative to the lateral areas while the person is sitting on the support contour, each posterior thigh protrusion area constitutes a support area; and

wherein;

shortening a functional length of the first connector member moves the pelvic protrusion area adjacent to the support member relatively more forward toward the pelvic area of the user.

13. A seat cushion comprising a resilient seat support structure having longitudinally-extending and transversely-extending sides intersecting at corners and defining an upward facing support contour extending between the sides to contact and support a person in a sitting position, comprising:

relief areas defined by the support contour and positioned adjacent to skin covering the ischial tuberosities, the greater trochanters and the coccyx and sacrum of a pelvic area of the person sitting on the support contour;

support areas defined by the support contour and positioned adjacent to skin covering tissue masses on opposite lateral sides of the posterior buttocks and beneath the proximal thighs of the person;

a support member positioned at a corner where a longitudinally-extending and a rear transversely-extending sidewall of the seat support structure intersect, the support member being relatively less flexible than the seat support structure to resist deformation of the support contour when contacted by the person seated on the seat cushion;

a longitudinal connector member that connects the support member to a longitudinally extending side of the seat support structure at a position longitudinally spaced from the corner where the support member is located, the longitudinal connector member restraining the support member to resist longitudinal deformation of the support contour at the corner where the support member is located;

a transverse connector member that connects the support member to a rear transverse extending side of the seat support structure at a position transversely spaced from the corner where the support member is located, the transverse connector member restraining the support member to resist transverse deformation of the support contour at the corner where the support member is located; and

wherein;

the relief areas and support areas are spaced relatively more away from and relatively more toward the pelvic area of the person, respectively, to establish relatively less pressure on the skin in the relief areas and relatively more pressure on the skin in the support areas and the support member supports the corner of the seat support structure to assist in maintaining the support contour of the seat support structure at the corner.

14. A seat cushion as defined in claim 13, wherein the longitudinal connector member adjusts to move longitudinally the support member and a portion of the seat support structure at the corner where the support member is located to alter the support contour.

15. A seat cushion as defined in claim 14, wherein the transverse connector member adjusts to move transversely the support member and a portion of the seat support structure at the corner where the support member is located to alter the support contour.

16. A seat cushion as defined in claim 13, wherein the transverse connector member adjusts to move transversely the support member and a portion of the seat support structure at the corner where the support member is located to alter the support contour.

17. A seat cushion as defined in claim 13, wherein one of the longitudinal or transverse connector members adjusts to move the support member and a portion of the seat support structure at the corner where the support member is located to alter the support contour.

18. A seat cushion as defined in claim 17, wherein the movement of the support member compresses a part of the seat support structure at the corner where the support member is located to alter the support contour at that location.

19. A seat cushion as defined in claim 13, wherein:

the support member is positioned at a first corner of the seat support structure, the support member positioned at the first corner being a first support member;

the longitudinal connector member connecting to the first support member being a first longitudinal connector member, the transverse connector member connecting to the first support member being a first transverse connector member; and

further comprising;

a second support member positioned at a second corner of the seat support structure;

a second longitudinal connector member that connects the second support member to the other of longitudinally extending sides of the seat support structure which is opposite of the one longitudinally extending side to which the first longitudinal connector member is connected;

a second transverse connector member that connects the second support member to the same rear transverse extending side of the seat support structure to which the first transverse connector member is connected; and

wherein;

the first and second support members reinforce the flexible seat support structure to maintain the support contour against significant deformation at the first and second corners in response to the user sitting on the cushion.

20. A seat cushion as defined in claim 19, wherein the first and second support members are moveable independently of each other.

21. A seat cushion as defined in claim 19, wherein the connector members comprise straps and the first and second longitudinal connector members are formed by portions of a single continuous strap.

22. A seat cushion as defined in claim 21, wherein a portion of the single continuous strap is connected to a bottom surface of the seat support structure.

23. A seat cushion as defined in claim 13, wherein the longitudinal connector member and the transverse connector member connector comprise straps.

24. A seat cushion as defined in claim 23, wherein the straps are made from nylon.

25. A seat cushion as defined in claim 23, wherein the straps include end portions that are connected together with hook and loop fasteners.

26. A seat cushion as defined in claim 25, wherein the transverse connector member connects to itself with hook and loop connectors to connect the support member to the rear transverse extending side of the seat support structure.

27. A seat cushion as defined in claim 25, further comprising:

an attachment strip that is connected to one of the longitudinally or rear transverse extending sides of the seat support structure, and wherein the connector member on the one of the longitudinally or rear transverse extending side connects to the attachment strip.

28. A seat cushion as defined in claim 23, further comprising:

a slotted connector pivotally connected to the support member and connecting the support member to one of the longitudinal or transverse connector members.

29. A seat cushion as defined in claim 23, further comprising:

a slot defined within the support member; and

wherein;

one of the longitudinal or transverse connector member loops through the slot to connect the support member to the seat support structure.

30. A seat cushion as defined in claim 19, further comprising:

a brace connected to extend a distance between a first point on the first support member and a second point on the second support member and to maintain the distance between the first point and the second point.

31. A seat cushion as defined in claim 30, wherein:

the connector members have functional lengths that are adjustable, the seat cushion further comprising;

a pivot joint connecting the first support member to the brace to allow the first transverse connector member to pivot the first support member transversely with respect to the brace by adjusting the functional length of the first transverse connector member; and

wherein;

the first support member is pivoted longitudinally by adjusting the functional length of the first longitudinal connector member.

32. A seat cushion as defined in claim 31, wherein:

the pivot joint connecting the first support member to the brace is the first pivot joint, the seat cushion further comprising;

a second pivot joint connecting the second support member to the brace to allow the second transverse connector member to pivot the second support member transversely with respect to the brace by adjusting the functional length of the second transverse connector member; and

wherein;

the second support member is pivoted longitudinally by adjusting the functional length of the second longitudinal connector member.

33. A seat cushion as defined in claim 32, wherein:

the first transverse connector member connects to the first support member and to the second pivot joint.

34. A seat cushion as defined in claim 32, wherein:

the second transverse connector member connects to the second support member and to the first pivot joint.