CANTILEVER SEAT

Abstract

The present invention relates to a cantilever seat cushion for reducing lower back strain, including: an inner pre-cut foam; an air tight shell that surrounds the inner pre-cut foam; an outer fabric cover that surrounds the air tight shell; an air valve that adjusts an incline angle of the cantilever seat cushion by deflating or inflating the seat in which the incline angle of the cantilever seat cushion is in a range from 10 to 25 degrees.

Claims

1. A cantilever seat cushion for reducing lower back strain, comprising: (a) an inner pre-cut foam; (b) an air tight shell that surrounds the inner pre-cut foam; (c) an outer fabric cover that surrounds the air tight shell; (d) an air valve that adjusts an incline angle of the cantilever seat cushion by deflating or inflating the seat, wherein the incline angle of the cantilever seat cushion is in a range from 10 to 25 degrees.

2. The cantilever seat cushion according to claim 1, wherein the inner pre-cut foam, the air tight shell, and the outer fabric cover are heat welded together.

3. The cantilever seat cushion according to claim 1, wherein the inner pre-cut foam is synthetic foam.

4. The cantilever seat cushion according to claim 1, wherein the inner pre-cut foam is an open cell polyurethane (PU).

5. The cantilever seat cushion according to claim 1, wherein the air tight shell is composed of plastic.

6. The cantilever seat cushion according to claim 5, wherein the plastic is at least one selected from the group consisting of polyvinyl chloride (PVC), thermoplastic polyurethane (TPU) and combinations thereof.

7. The cantilever seat cushion according to claim 1, wherein the outer fabric cover is natural, synthetic, woven, knitted or a combination thereof.

8. The cantilever seat cushion according to claim 1, wherein the cantilever seat cushion has an incline angle of 15 to 22 degrees.

9. The cantilever seat cushion according to claim 1, wherein the cantilever seat cushion has an incline angle of 20 degrees.

10. The cantilever seat cushion according to claim 1, wherein the air valve is a quick air release valve.

11. The cantilever seat cushion according to claim 1, wherein the air valve is attached to a plastic tube.

12. The cantilever seat cushion according to claim 1, wherein the air valve is DC or AC powered.

13. The cantilever seat cushion according to claim 12, further comprising a remote control to operate the DC or AC powered air valve for inflation or deflation.

14. The cantilever seat cushion according to claim 1, said cantilever seat cushion having a front side height (F) of 3 to 8 inches.

15. The cantilever seat cushion according to claim 1, said cantilever seat cushion having a rear side height (R) of 1 to 4 inches.

16. The cantilever seat cushion according to claim 1, said cantilever seat cushion having a depth (D) of 8 to 20 inches.

17. The cantilever seat cushion according to claim 1, said cantilever seat cushion having a width size (W) of 10 to 26 inches.

18. A cantilever seat cushion for reducing lower back strain, comprising: (a) an inner pre-cut foam; (b) an air tight shell that surrounds the inner pre-cut foam, wherein the air tight shell is any type of fabric having an air tight backing material or laminated with an air tight material; (c) an air valve that adjusts an incline angle of the cantilever seat cushion by deflating or inflating the seat, wherein the incline angle of the cantilever seat cushion is in a range from 10 to 25 degrees.

19. A method for reducing lower back strain in a human subject, comprising: placing the cantilever seat cushion according to claim 1 onto a seat, wherein a wide portion F is situated on a forward part of the seat and a narrow portion R is situated on a rear part of the seat, wherein lower back strain in the human subject is reduced when sitting on the cantilever seat cushion.

20. The method according to claim 18, wherein the human subject adjusts the incline angle of the cantilever seat cushion by opening the air valve.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0035] FIG. 1 is a front view of a male pelvis.

[0036] FIG. 2 is a front view of a female pelvis.

[0037] FIG. 3 is a left view of a human body, with a line representing the center of gravity.

[0038] FIG. 4 is a rear view of the pelvis and ligaments.

[0039] FIG. 5 is a front view of a human skeleton.

[0040] FIG. 6 is a front view of the Femoral head and hip socket joint.

[0041] FIG. 7 is a front view showing the connection of the Femoral head and the Femoral neck of the femur to the pelvis.

[0042] FIG. 8 is a diagram showing the contour of a male person sitting on a sofa.

[0043] FIG. 9 is a diagram showing the contour of a male person sitting on the inclined surface of the Cantilever seat.

[0044] FIG. 10 is a maquette showing normal forces, corresponding forces and the Moments on an inclined surface.

[0045] FIG. 11A is a left view force diagram representing the cantilever effects in an embodiment of the present invention at the knee.

[0046] FIG. 11B is a left view force diagram representing the cantilever effects in an embodiment of the present invention at the thigh and the femur.

[0047] FIG. 12 is the left and right views of the Cantilever seat.

[0048] FIG. 13 is drawing of an embodiment of the Cantilever seat.

[0049] FIG. 14 is drawing of yet another embodiment of the Cantilever seat.

[0050] The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawings will be provided by the Office upon request and payment of the necessary fee.

DETAILED DESCRIPTION OF THE INVENTION

[0051] The Cantilever Seat is primarily for use by people with back and lower back pain. It is troubling for people with back and lower back pain to sit on sofas, chairs, and plane seats for extended periods of time because these people feel extreme pain when they get up and begin moving around.

[0052] This product is inflatable and adjusts its height and firmness according to each individual's weight, limberness, movement and motion. People with back and lower back pain have to get up from the sitting position slowly and carefully. It is very hard to get up from the Cantilever Seat when it is fully inflated.

[0053] As mentioned above, about of the thigh weight (i.e., 28.32% of body weight) is on a human pelvis. For a person weighing 180 lbs, this amounts to 18 lbs. This amount of weight is no longer carried on the pelvis when the Cantilever Seat of the present invention is used.

[0054] Nearly all of the 28.32% weight of the two thighs, which are about 36 lbs for a person weighing 180 lbs, rest on the inclined Cantilever Seat. FIG. 13 shows the shape of the Cantilever seat.

[0055] Moving a person's body left or right and back or forth, while sitting on the stationary sitting bones is not with physical ease, and puts much stress on the fine muscles, tendons, ligaments, veins and nerves in the pelvis area. On the other hand, moving a person's body left or right and back or forth, while sitting on the Cantilever Seat is much easier because the large Femoral head can easily move inside the socket joint of the hip.

[0056] The hip joint is located between the femur and the pelvis. The primary function of the hip joint is supporting the body weight in both static (e.g. standing) and dynamic (e.g. walking or running) postures. The hip joints are important in retaining the physical structural balance of a person.

[0057] In one embodiment, the Cantilever seat is equipped with an air valve, as shown in FIG. 13 as 1310 and FIG. 14 as 1410. The Cantilever seat is made of any rigid plastic material that is readily available on the market. The seat deflates by twisting the valve counter clock-wise to open, and pressing or sitting on it. The seat re-inflates by leaving the air valve open. For extra stiffness, a person can add air and close the valve clockwise. The valve can be located on the left-side, front-side or the right-side of the Cantilever seat. In another embodiment, the air release valve may be attached to a plastic tube for accessibility by handicapped persons.

[0058] In another embodiment, the air valve can be a DC battery or AC powered mini air valve with a switch to inflate or deflate the Cantilever seat. The mini air valve may have a remote control to deflate or inflate the seat.

[0059] In yet another embodiment, the seat may also have a quick air release valve in addition to the above mentioned valves. The quick air release valve is air tight with a cap. The air in the seat can be released quickly by pulling the cap away from the seat. It is made of any semi-rigid plastic that is readily available in the market. It may be located on the left-side, front-side or the right-side of the Cantilever seat.

[0060] FIG. 8 shows the femur position and the contour of a male person sitting on a sofa. The lumbar and lower back are not supported by a sofa's back cushion. The upper body (head, neck, arms and trunk), which is about 60% of total body's weight, is carried on the two sitting bones (Ischium bones). Also, about of the thighs' weight is carried over the same two sitting bones. That is an additional 10% of the body's total weight. Please see Table. 1. Most of this 60% that includes abdominal weight is off center from the sitting bones. This tends to create a cantilever force on the lower spine. The lower spine is not a rigid structure, and the body's lumbar tends to curve away from sitting bones and the sofa's back cushion because of the abdominal weight and the body's center of gravity

[0061] FIG. 9 shows the femur position and the contour of a male femur position on a sofa with an inclined Cantilever Seat. FIG. 9 illustrates the lower back and lumbar resting on the sofa back cushion. The force due to gravity (weight) of the legs and feet on the inclined seat includes: [0062] a) The Normal force that is a perpendicular force exerted on the femur at the knee joint. The Normal force pushes up at the other end of femur at the hip joint socket. [0063] b) The corresponding force component acts along the incline direction on the femur. The corresponding force pushes the femur at the hip joint against the seat back cushion.

[0064] Similarly the weight of the thighs on the incline surface of the Cantilever seat creates a Normal force and a corresponding force. Again, the Normal force pushes up the other end of the femur at the hip joint socket, and the corresponding force pushes the femur at the hip joint against the seat back cushion.

[0065] The two vertical forces at the hip joint socket, which are close to the body's center of gravity, lift the trunk off the seat, thereby reducing pressure on the two sitting bones. The two forces created along the incline surface of the Cantilever seat push the pelvis against the seat back cushion.

[0066] Nearly all sofas, chairs and seats in homes and office furniture, vehicles, trains and airplanes are slanted backwards. Also, the spine is composed of 33 interlocking bones (vertebrae) that are separated by soft, compressible discs supported by many ligaments and muscles.

[0067] The combination of four forces, mentioned above, lift the body and push the lower back and lumbar over the sofa back cushion. As a result, the upper body and the sitting bones are lifted up, and the pelvis and the lumbar are straightened. The straightened lower back and lumbar help the spine become upright and erect. The shoulders move back, the chest opens-up, breathing become easier, and the upper body posture improves.

[0068] FIGS. 10 and 11A show the forces by gravity (weight) of the feet and legs pulling down the femur where: [0069] LW: Leg weight (force due to gravity), [0070] VFL: force perpendicular to the femur at the knee joint (LWCos 1), [0071] HFL: Corresponding force acting on femur along incline surface of seat (LWSin 1), [0072] DkL: Distance from axis of knee to reference point on the Femoral head at the Hip joint, [0073] DfL: Distance from axis of the femoral head to reference point on the femur, [0074] : Inclined angle of Cantilever seat, [0075] VTL: Moment of force acting on the Femoral head at the Hip joint socket, [0076] HFL: Corresponding force pushing femur at hip joint against seat back cushion. [0077] Moment of force: is defined with respect to a fixed (reference point), and relates to physical quantities as measured at some (distance) from that reference point. For example, the Moment of force acting on an (object), often called torque, is the product of the force and the distance from a reference point.

[0078] The Moment of force acting on the Femoral head at the Hip joint socket that pushes up the two sitting bones is: VTL=2VFLDkL:Df.

[0079] The corresponding force that pushes the femur at the hip joint against the seat back cushion is =2HFL.

[0080] FIGS. 10 and 11B show the forces that are created by gravity (weight) of the thighs. The weight of the thighs sliding over the inclined Cantilever Seat towards the sofa back cushion creates vertical and horizontal forces on the femur. The downward vertical force pulls up the end of the Femoral head at the hip joint socket. The horizontal force pushes the pelvis against the sofa back cushion: [0081] TW: Thigh weight (force due to gravity), [0082] VFT: Force perpendicular to femur (TWCos ), [0083] HFT: Corresponding force acting on femur along incline surface of seat (TWSin ), [0084] CHM: Center of hip mass as the mean position of the entire hip mass distribution, [0085] DrC: Distance from CHM to reference point on femur, [0086] DrF: Distance from axis of Femoral head to reference point on the femur, [0087] : Incline angle of Cantilever seat, [0088] VTT: Moment acting on Femoral head at Hip joint socket, [0089] VCT: Corresponding force pushing femur at hip joint against seat back cushion, [Femoral head] . . . [Reference point] . . . [CHM] . . . [Knee joint]

[0090] The Moment of force acting on the Femoral head at the Hip joint socket that pushes up the two sitting bones is: VTT=2VFTDrC:DrF.

[0091] The corresponding force that pushes the femur at the hip joint against seat back cushion is: VCT=2HFT.

[0092] The above four forces acting on the femur and the Femoral head lift up the sitting bones off the seat and push the pelvis and the lumber against the seat back cushion. The magnitude of these four forces may be estimated, but expensive scientific instruments are necessary to make accurate calculations.

[0093] FIG. 12 shows photos of the left and right sides of the Cantilever seat, which includes the following parts: [0094] (a) The inner part is a pre-cut foam. It can be made of any type of synthetic foam. The open cell thermosetting polyurethane (PU) is the preferred material. The foam cut is shown in FIGS. 13 and 14, except it has all 8 edges and 8 corners straight before assembly. [0095] (b) The foam (a) above is sandwiched with an air tight shell that covers top, bottom and all the sides. The air tight shell can be composed of any air tight material. Preferably, the air tight shell material is PVC, Thermoplastic polyurethane (TPU) and combinations thereof. TPU is any of a class of polyurethane plastics with many properties, including elasticity, transparency, and resistance to oil, grease and abrasion. The air tight shell layer on top and the bottom are large enough to cover all four sides and extend beyond the foam boundaries of about 1. [0096] (c) The air tight shell (b) above is covered with any type of natural, synthetic, hand made woven or knitting fabric. The fabric on the top and the bottom are large enough to cover all four sides and extend beyond the foam boundaries of about 1. [0097] (d) The air tight shell (b) and the outer fabric (c) may be replaced by any type of fabric having air tight backing material or may be laminated with an air tight material. The fabric on the top and the bottom are large enough to cover all four sides and extend beyond the foam boundaries of about 1. [0098] (e) The product is equipped with an air release valve and may also have a quick air release valve as discussed above.

[0099] The air release valve is placed between the top and bottom layers of the air tight shell b) on the left, the right or the front side of the Cantilever seat. Then, it is placed in a mold pressed and heated. The synthetic foam, the air tight shell and the cover fabric are heat welded together. This process produces a welded seam that projects out where the upper and lower air tight shell and the fabric cover meet. The welded seam (e.g., 1) around the sides of the Cantilever seat is carefully trimmed to about .

[0100] The same procedure applies for making the Cantilever seat when an air-tight synthetic laminated fabric or, a fabric with air-tight syntactic backing is used in place of the air tight shell (b) and the cover fabric (c).

[0101] The Cantilever seat can be inflated and deflated. It can be deflated by opening the valve, pressing hard on the seat, closing the valve to prevent air returning back in the seat, and rolling the seat for storage or carrying. The valve remains closed when it is rolled up. The Cantilever seat has a cylindrical shaped carry bag made from any type of fabric.

[0102] To use the seat, the air release valve is opened, foam expands and sucks air into the seat. Once the foam has fully expanded, the valve is closed and the Cantilever seat is ready for use.

[0103] There are many conventional seats, back support, lumbar support, neck support and pillows made from memory foam and other materials that exist in the market. However, the height and stiffness of the conventional seats are not adjustable to the weight of a person. Moreover, conventional seats have a different orientation from the Cantilever seat, i.e., they slope towards the front. On the contrary, the Cantilever seat slopes towards the rear of the seat.

[0104] Unlike memory foams, the seat cushion of the present invention can be finely tuned and adjusted for height and stiffness to a person's weight, size and comfort. The support and Normal pressure on the thigh's contour are very evenly distributed. Most of the upper body weight is carried on the Femoral heads, the femurs and the thighs, not on our sitting bones.

[0105] Memory foams, often used by handicapped people for time periods of hours or longer, need to be washed due to body perspiration penetrating in the foam. However, body perspiration cannot penetrate into the Cantilever seat.

[0106] Because of the shape, ability to adjust height, adjust stiffness and adjust resilience, tests have shown that the Cantilever seat of the present invention has a wide range of applications.

[0107] The present invention can be used for lower back pain, lumber support, neck support, posture improvement, as a pillow, and can be placed under the thighs when lying down to relieve back pain.

[0108] The present invention can be made in different colors and sizes suitable for use by people of all ages, weights and heights.

[0109] The Cantilever seat can be used on any chair, sofa, vehicle, train, airplane, etc.

[0110] The Cantilever Seat can be used as a standalone, on top of, or incorporated into seats (e.g., sofas, chairs, recliners, seats of any vehicles, such as airplanes, trucks, buses, minibuses, vans, cars, and wheelchairs).

[0111] FIGS. 13 and 14 are drawings of the Cantilever seat. F is front side height, R is rear side height, D is the depth size and W is the width size of the Cantilever seat. The edges and corners 1311 to 1322, and 1411 to 1422 can be straight or rounded depending on how much the air tight shell and the fabric are stretched over the foam. Parts 1310 and 1410 are the air release valves. Parts 1323 and 1423 are seam lines where the air tight shell and fabric are heat welded. The foam, shell and the fabric must be heat welded together on all surfaces of the Cantilever seat to be functional and effective.

[0112] The incline angle's broad range is 10 to 25 degrees, more preferably 15 to 22 degrees, and most preferably 20 degrees. The user can adjust the incline angle by releasing air when sitting on the Cantilever seat.

TABLE-US-00002 TABLE 2 Seat size ranges when used as stand alone Most Broad Range More preferably Preferably F 3 to 8 inches 4 to 6 inches 4.5 inches R 1 to 4 inches 2 to 4 inches 1.5 inches D 8 to 20 inches 12 to 16 inches 13 inches W 10 to 26 inches 16 to 22 inches 18 inches

[0113] Although the invention has been explained in relation to its preferred embodiments, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed. The concept of this invention can be incorporated into and be part of the body of a seat (e.g., chair, sofa, seat of any vehicle, such as trains, cars and airplanes).

REFERENCES

[0114] 1. DEYO, M D, Richard A. Watch Your Back. Cornell University Press, 2014. [0115] 2. Mckenzie, Robin. Treat Your Own Back. Orthopedic Physical Therapy Products, 2010.