Method for manufacturing wheelchair seat

Abstract

To provide a method for manufacturing a wheelchair seat which is suitable for wheelchair sports and is devised so as to easily and quickly make a made-to-order seat fitted for a user.SOLUTION: The method for manufacturing a wheelchair seat includes: a first step k1 of preparing the wheelchair frame 1 with the seat member 25 for supporting the weight; a second step k2 of placing the polyethylene bag 23 on the seat member 25; a third step k3 of injecting the foaming material h into the polyethylene bag 23 to form a foaming base body 21; a fourth step k4 of forming the hip seat shape 22 in the uncured foaming base body 21 by the seating of the user U on the polyethylene bag 23; a fifth step k5 of removing the seat member 25 from the wheelchair frame 1, a sixth step k6 of setting the foam base 21 contained in the large polyethylene bag 24 on the seating area 1A of the wheelchair frame 1 from which the seat member 25 has been removed; and a seventh step k7 of blowing foam material h onto the foam base 21 and the wheelchair frame 1 in the large polyethylene bag 24 to position the foam base 21 on the wheelchair frame 1.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a wheelchair seat, and more particularly to a method for manufacturing a seat suitable for wheelchairs used for competitions and sports. [Background technology]

[0002] Wheelchair seats generally have a structure in which a seat member made of fabric or the like is stretched across left and right seat pipes. For example, as shown in Patent Document 1, a structure in which a seat (22) is supported by left and right main pipes (211) is known, and as shown in Patent Document 2, a structure in which a wheelchair seat (1) made of quilted fabric is provided is known. Also, as disclosed in Patent Document 3, a seat structure in which a thick cushion material is placed over the seat member to improve the user's sitting comfort is known.

[0003] On the other hand, in the case of athletic wheelchairs intended for sports such as ball games like wheelchair basketball and wheelchair tennis, not only is a lightweight, easy-to-move, and sturdy wheelchair desirable, but a good sense of unity between the user (athlete) sitting in the wheelchair is also important. For example, the athletic wheelchair shown in Patent Document 4 has a seat (seat portion: 20) in which the seat surface portion (20a) and backrest portion (20b) are curved inward to fit the shape of the user's hips and back, as disclosed in paragraph 0027 and Figures 1 and 2 of the specification. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6483791 [Patent Document 2] Registered Utility Model No. 3139269 [Patent Document 2] Japanese Patent Publication No. 2020-99596 [Patent Document 3] Patent No. 6976614 Summary of the Invention [Problem to be solved by the invention]

[0005] The wheelchair seat disclosed in the aforementioned Patent Document 4 is suitable for sports because it has a shape and size that fits the shape of the human body better than the general seats disclosed in Patent Documents 1 to 3. However, a shape that is simply curved inward has limitations on the fit, and there is a demand for a seat that fits the user's body shape better and provides a more integrated fit.

[0006] The object of the present invention is to provide a method for manufacturing a wheelchair seat that is devised to enable simple and quick production of a made-to-order seat that fits the user well, for example, to realize a seat with a sense of unity that is suitable for wheelchair sports. [Means for solving the problem]

[0007] [1] The present invention provides a method for manufacturing a wheelchair seat, A first step of preparing a wheelchair frame having a seat member that supports the weight of a user; a second step of placing a bag-shaped body on the sheet member; a third step of blowing a foam material into the bag-shaped body to form a foam base; a fourth step of forming a buttocks seating shape in the foam base by a user sitting on the bag-shaped body while the foam base is in an uncured state; a fifth step of removing the seat member from the wheelchair frame; a sixth step of setting the foam substrate contained in the bag-shaped body in the seating portion of the wheelchair frame from which the seat member has been removed; a seventh step of blowing foam material onto the foam substrate and the wheelchair frame within the bag to position the foam substrate relative to the wheelchair frame; The present invention is characterized by having the following.

[0008] According to the method for manufacturing a wheelchair seat of the present invention, when creating a seat using a lightweight, highly moldable foam material, the actual wheelchair frame can be used as a mold for the foam material by blowing the foam material into a bag-shaped body. In other words, the bag-shaped body that receives the foam material can be deformed to fit the shape of the wheelchair frame, so the wheelchair frame, via the bag-shaped body, essentially functions as a mold for the foam material, thereby enabling the formation of a foam base shaped to fit the wheelchair frame. In the fourth step, the user's buttocks are molded directly into the foam base, allowing the creation of a seat that fits the user's buttocks better. After the seventh step, the hardened foam base can be placed on the wheelchair frame, allowing the user to sit on the foam base and test ride.

[0009] [2] The second invention is the method according to [1], The seat member is a belt-like body stretched over left and right seat pipes of the wheelchair frame, and the first step includes a step of loosening the tension of the belt-like body. [3] The third aspect of the present invention is the method according to [1] or [2], The foam material is urethane foam. [4] The fourth aspect of the present invention is any one of [1] to [3], The fourth step includes a step of forming a lumbar support portion in the foam base by blowing a foam material onto a lumbar support member provided on the wheelchair frame and the lumbar region of the user inside the bag-shaped body while the user is seated on the foam base from above the bag-shaped body. It is characterized by: [5] The fifth aspect of the present invention is the method according to [4], The seventh step is characterized by including a step of blowing foam material onto a frame pipe that passes behind the lumbar support portion of the wheelchair frame and onto the back surface of the lumbar support portion inside the bag-shaped body while the lumbar support member is removed from the wheelchair frame, thereby engaging the frame with the lumbar support portion. [6] The sixth aspect of the present invention is any one of [1] to [5], The seventh step is characterized by including a step of blowing foam material onto a frame pipe that passes under the foam base in the wheelchair frame and onto the bottom of the foam base inside the bag-shaped body to form a bottom support portion on the foam base. [7] The seventh aspect of the present invention is any one of [1] to [6], The method is characterized by including an eighth step of removing the foamed substrate that has been subjected to the seventh step from the bag-shaped body and adjusting its appearance. [Effects of the Invention]

[0010] According to the present invention, by innovating the process of blowing foam into a bag-shaped body placed on the wheelchair frame, it is possible to obtain a seat that fits well to both the user's body shape and the wheelchair frame, and it is also possible to manufacture the seat in a short period of time, for example, by taking a mold of the user's buttocks and mounting the seat on the wheelchair for a test ride on the same day.As a result, it is possible to provide a manufacturing method for wheelchair seats that is devised to easily and quickly produce made-to-order seats that fit the user well. [Brief explanation of the drawings]

[0011] [Figure 1] A perspective view from above and to the side showing an example of a racing wheelchair with both wheels removed. [Figure 2] A perspective view of the wheelchair in Figure 1, seen from above and in front [Figure 3] 1 is a diagram showing first to third steps in a method for manufacturing a wheelchair seat. [Figure 4] 4 is a diagram showing the fourth to sixth steps in the manufacturing method of a wheelchair seat. [Figure 5] A diagram showing the seventh step in the manufacturing method of a wheelchair seat. [Figure 6] 10A and 10B are perspective views showing the sheet after the seventh step and the eighth step; [Figure 7] Flow diagram showing a manufacturing method for a wheelchair seat DETAILED DESCRIPTION OF THE INVENTION

[0012] The following describes in detail the embodiment of the wheelchair and the method for manufacturing a wheelchair seat according to the present invention with reference to the drawings, but the present invention is not limited to the illustrated examples and can be implemented with appropriate modifications within the scope of the above and below mentioned purposes, all of which are included in the technical scope of the present invention. Also, the dimensions, shapes, proportions, etc. of the various parts in the drawings may not necessarily be the same as the actual products.

[0013] 1 and 2 show an example of a sports wheelchair (hereinafter simply referred to as "wheelchair") C suitable for use in ball sports such as wheelchair basketball and wheelchair tennis. This wheelchair C is composed of a wheelchair frame 1 made of pipe material, left and right bearing portions 2A, 2A for supporting the main wheels 2 (see the imaginary lines in FIG. 1), left and right front wheels 3, 3, a single rear wheel 4 in the center of the left and right, a seat 5, and foot supports 6. The pair of front wheels 3, 3 and the rear wheel 4 are preferably caster wheels. Note that FIGS. 1 and 2 show the wheelchair C with the left and right main wheels 2 removed.

[0014] The wheelchair frame 1 preferably comprises a pair of left and right main pipes 7, 7 that extend front to back with an upward tilt at the rear, a pair of left and right seat pipes 8, 8 that are installed above each main pipe 7 and straddle the front and rear of each main pipe, a front end pipe 9 that connects the front ends of the left and right main pipes 7, 7 and extends left and right, an axle pipe 10 that connects the front and rear middle portions of the left and right main pipes 7, 7, and a rear frame portion 11 that supports the rear wheels 4. The left and right seat pipes 8, 8 are connected relative to each other by a front connecting pipe 12 that has an upwardly open U-shape. The front connecting pipe 12 is provided at a position midway between the left and right seat pipes 8, 8 and toward the front, so as to bypass the lower portion.

[0015] It is preferable that the left and right ends of the front end pipe 9 protrude laterally to the left and right, respectively, to serve as bumpers, and that each side protrusion 9L, 9R and the main pipes 7, 7 are connected by bolting a pair of upper and lower triangular reinforcing plates 14, 14. The rear of each main pipe 7 is formed into an upright rear portion 7B that is bent upward and stands above the rear end of the seat pipe 8, and it is preferable that a reinforcing pipe 17 is provided that diagonally connects each of the left and right upright rear portions 7B and each of the seat pipes 8 above the seat pipe 8.

[0016] A hanging pipe support boss 7A is preferably fixed to the inside front portion of each main pipe 7 by welding or other means, and a step frame 6A is inserted into each support boss 7A so that its height is adjustable. Each step frame 6A preferably comprises a vertical pipe section 16 that faces up and down and is inserted into the support boss 7A, and a horizontal pipe section 15 that is integrated with the lower end of the vertical pipe section 16 by welding or other means. Foot supports 6 made of, for example, steel plate are attached to the left and right horizontal pipe sections 15, 15, and it is preferable that the left and right step frames 6A, 6A are integrated by these foot supports 6.

[0017] 1 and 2, it is preferable that leg restraining belts 18 acting on the thighs from above be provided straddling the upper front parts of the left and right seat pipes 8, 8, and it is also convenient that lower leg restraining belts 19 acting on the calves from behind be provided straddling the lower front parts of the left and right seat pipes 8, 8. It is also preferable that foot restraining belts 35 capable of holding the feet placed on the foot supports 6 be provided on the foot supports 6.

[0018] As shown in FIGS. 1 and 2, the seat 5 is a bucket seat in which the seating portion 5A and the lumbar support portion 27 are integrated. The seating portion 5A of the seat 5 rests on a front connecting pipe 12 oriented left and right that connects the front and rear middle portions of the left and right seat pipes 8. The lumbar support portion 27 of the seat 5 is located in front of a back connecting pipe 13 oriented left and right that connects the upright rear portions 7B of the left and right main pipes 7, and is provided with a support portion (not shown) that is in surface contact with the left and right rear portions 7B so as to bite into them. In other words, it is preferable that the load acting on the seat 5 be supported by the front connecting pipe 12 and the left and right rear portions 7B. Note that the seat 5 may be positioned by the left and right reinforcing pipes 17, the back connecting pipe 13, or a protective member 34 made of cushioning material wrapped around the back connecting pipe 13.

[0019] It is preferable that a two-point seat belt 20 that acts on the base of the user's left and right thighs is provided via the seat 5. The seat belt 20 is attached to the rear of the left and right main pipes 7, 7, passing through the upper sides of the left and right seat pipes 8, 8 and reinforcing pipes 17, 17 that are upside down L-shaped in a side view, and is preferably worn through elongated through-holes 5c formed in the left and right side wall portions 5C, 5C of the seat 5, respectively.

[0020] Between the left and right side walls 5C, 5C, the seating portion 5A of the seat 5 has left and right thigh recesses 5a, 5a on which the user's thighs rest, a raised portion 5e between the left and right thigh recesses 5a, 5a, and a support surface 5d on which the user's buttocks rest, giving the seating portion 5A a generally W-shaped upper surface shape in front view (see Figure 2). The seat 5 has a lumbar support portion 27 that follows the seating portion 5A. The lumbar support portion 27 has a lumbar support surface 5b that recesses toward the rear and is curved so that its back is supported by the left and right upright rear portions 7B, 7B. The hatched areas (notation omitted) on the inner surface of the seat 5 are surface reinforcement areas made of fiber material or the like (see Figures 1 and 2).

[0021] [About the manufacturing method of Sheet 5] Next, a manufacturing method for the seat 5 will be described with reference to Figures 3 to 7. The seat 5 and wheelchair frame 1 used to illustrate the manufacturing method in Figures 3 to 6 are different from the seat 5 and wheelchair frame 1 shown in Figures 1 and 2, but are manufactured in the same way. The upper parts of Figures 3 and 4 and the middle parts of Figure 4 are drawn in a front-to-rear view of the main parts using a cross section that intersects the left and right seat pipes 8, 8 from left to right, and the lower part of Figure 4 and Figure 5 are drawn in a side view of the upper part of the wheelchair frame 1. For simplicity, the upper part of the plastic bag 24 has been omitted from the lower part of Figure 5.

[0022] A method for manufacturing a seat 5 will be described for a wheelchair used in sports such as wheelchair basketball. As shown in Figures 3 to 6, the wheelchair frame 1 used by a user U is prepared, and the user U is also invited to the work site. Using plastic bags 23, 24 and urethane foam h, a bucket-shaped seat 5 is made from a mold of the user U's buttocks d and lower back y, and then mounted on the wheelchair C, allowing for a test ride on the same day. Note that the seat 5 and wheelchair frame 1 used to illustrate the manufacturing method in Figures 3 to 6 are different from the seat 5 and wheelchair frame 1 shown in Figures 1 and 2, but the manufacturing method for the seat is the same for both.

[0023] As shown in the flow chart of FIG. 7, the manufacturing method of the seat includes a first step k1 of preparing a wheelchair frame 1 having a belt-like body (an example of a seat member) 25 that supports the weight of a user U, a second step k2 of placing a small plastic bag (an example of a bag-like body) 23 on the belt-like body 25, a third step k3 of blowing urethane foam h into the inside of the small plastic bag 23 to form a foam base 21, and a third step k4 of blowing urethane foam h into the foam base 21 when the user U sits on the small plastic bag 23 while the foam base 21 is still in an unhardened state. The method includes a fourth step of forming the buttock seating form 22, a fifth step k5 of removing the belt-like body 25 from the wheelchair frame 1, a sixth step k6 of setting the foamed base 21 contained in a large plastic bag (an example of a bag-like body) 24 in the seating area 1A of the wheelchair frame 1 from which the belt-like body 25 has been removed, and a seventh step k7 of blowing urethane foam h onto the foamed base 21 and the wheelchair frame 1 inside the large plastic bag 24 to position the foamed base 21 relative to the wheelchair frame 1. Note that the wording shown in the flow chart may not necessarily match the wording shown in the claims.

[0024] The manufacturing method will now be described in detail. First, as shown in the upper part of Fig. 3, the first step k1 of preparing the wheelchair frame 1 includes a relaxation step k1s of fully relaxing the tension of the belt-like body 25 (shown by an imaginary line) stretched between the left and right seat pipes 8, 8 in the prepared wheelchair frame 1, so that the belt-like body 25 hangs down significantly as indicated by the white arrow. Wheelchairs C that are actually being used by a user U and that are brought to a manufacturing site for a new seat (the seat of the present invention) often come with the belt-like body 25 attached as the seat 5 or as a strength member on which a cushion seat (see Patent Document 3) is placed.

[0025] The belt-like body 25 is where the user U sits, either directly or indirectly via a separate cushion sheet, and is provided with sufficient strength to support the weight of the user U. As shown in the upper part of Fig. 5, the belt-like body 25 has a seat portion 25A that is rectangular, such as a square, in plan view, and fastening belts 25B at multiple locations, such as four locations at the front and rear, and is attached in a tensioned state by being wound around the left and right seat pipes 8, 8. Each fastening belt 25B has a first belt piece 25a and a second belt piece 25b extending respectively from the left and right ends of the seat portion 25A, and it is preferable that the belt-like body 25 can be stretched around the left and right seat pipes 8, 8 in a desired tensioned state by hook-and-loop fasteners 28 having engaging and non-engaging portions at the ends of each of the first and second belt pieces 25a, 25b.

[0026] In the first step k1, it is preferable to carry out a loosening step k1s in which the engagement positions of the hook-and-loop fasteners 28 are adjusted in the longitudinal direction of the belt pieces 25a, 25b to substantially extend the lengths of the first and second belt pieces 25a, 25b and fully loosen the fastening belts 25B. The seat portion 25A and / or the fastening belts 25B are often made of an elastic or flexible material so as to easily fit the left and right seat pipes 8, 8 and the buttocks d of the user U, but this is not essential. In this way, it is preferable to extend the left-right length of the belt-like body 25 so that the left-right central region hangs down significantly (see the upper diagram in Figure 3).

[0027] In the second step k2, as shown in the middle of the top and bottom of the drawing in Fig. 3, a relatively small plastic bag 23 is prepared (or prepared), and the prepared small plastic bag 23 is placed horizontally on the loosened belt-like body 25. In this case, it is desirable to place the small plastic bag 23 with its opening 23A facing forward. The small plastic bag 23 used here is preferably one whose left-to-right width is slightly wider than the overall width of the left and right seat pipes 8, 8 and whose front-to-back length is sufficiently longer than the front-to-back length of the belt-like body 25 (e.g., 1.2 to 2 times the front-to-back length of the belt-like body 25), as this effectively prevents the urethane foam from scattering or leaking when spraying the urethane foam or when making a buttocks seat mold (described later).

[0028] As shown at the bottom of FIG. 3, the third step k3 involves using a spray gun 31 to spray urethane foam (h) into the small plastic bag 23 through the opening 23A, thereby creating a foamed substrate 21 that can be placed on the belt-like body 25 inside the small plastic bag 23. In this case, it is preferable to spray the urethane foam (h) sequentially from the back of the small plastic bag 23 toward the opening 23A while swinging the spray gun 31 from side to side, but this is not limited to this procedure. Reference numeral 32 denotes a supply tube from a canister (not shown) of the urethane foam (h) concentrate. The urethane foam (h) is preferably a two-component mixture type with a foaming ratio of 30, but other types are also acceptable. In the third step k3, it is preferable to spray the urethane foam (h) so that it has a slight thickness above and below the left and right seat pipes 8, 8 (so that the side placement portions 21L, 21R, described below, are formed).

[0029] 4, the fourth step k4 is a step in which the user U actually sits on the foam base 21 through the small plastic bag 23 while the urethane foam h sprayed into the small plastic bag 23 in the third step k3 is still in an uncured state, such as semi-cured, to form a seating mold 22 for the user U's buttocks in the foam base 21. In this case, the user U's weight causes the buttocks d to press the foam base 21 against the belt-like body 25, but the belt-like body 25 has sufficient strength to support this load, which is advantageous. By this fourth step k4, a mold 22 with the exact shape and size of the user U's buttocks can be formed in the foam base 21. In the fourth step k4, it is preferable that the foamed urethane h flows to the left and right when the user U sits down, forming side mounting portions 21L, 21R that rest on the left and right seat pipes 8, 8, but both or / and either the left and right side mounting portions 21L, 21R may already be formed in the third step k3.

[0030] When making a seat 5 having a lumbar support portion 27, it is preferable to perform a plastic bag exchanging step ku and a lumbar support forming step kk in the fourth step. The plastic bag exchanging step ku involves transferring a relatively small plastic bag 23 that is large enough to fit a foam base 21 corresponding to the seating portion 5A into a large plastic bag 24 that can easily fit the foam base 21 with the lumbar support portion 27 (see the upper side of FIG. 5). Specifically, as shown in the middle of the top and bottom of FIG. 4, the plastic bag exchanging step ku is a step of removing the foam base 21 having the buttock seat mold 22 from the small plastic bag 23 that contains the foam base 21 and replacing it with a large plastic bag 24 that is larger than the small plastic bag 23. When placing the large plastic bag 24 containing the foamed base 21 on the belt-like body 25, as shown at the bottom of Figure 4, the foamed base 21 is inserted all the way into the large plastic bag 24 with the opening 24A facing backward, and the part of the large plastic bag 24 on the opening 24A side, i.e., the part where the foamed base 21 is not present and is left over as a bag, is folded upward so that the opening 24A faces upward.

[0031] For ease of distinction, the plastic bag 23 is referred to as the small plastic bag 23 and the plastic bag 24 as the large plastic bag 24, but the plastic bag 23 may also be referred to as the first plastic bag 23 and the plastic bag 24 as the second plastic bag 24. Also, if only one bag-shaped body is used, such as when the large plastic bag 24 is used from the beginning, the plastic bag replacement step ku can be omitted.

[0032] The lumbar support forming process kk is a process in which, as shown at the bottom of Figure 4, the user U is seated on the buttock seat mold 22 of the foam base 21 from above the large plastic bag 24 placed on the belt-like body 25, and foamed urethane h is blown into the inside of the large plastic bag 24 from the upward opening 24A onto the lumbar support member 26 and the lumbar region y of the user U to form the lumbar support portion 27.

[0033] In a preferred example of the lumbar support forming step kk, as shown at the bottom of FIG. 4, the user U is in a slightly bent-forward position (see the main part y indicated by the imaginary line), and a spray gun 31 is inserted through the opening 24A to spray urethane foam h onto the user U's lumbar region y, the lumbar support member 26, and the area between them. Reference numeral 26A denotes the front cover portion of the lumbar support member 26, and it is preferable that the front cover portion 26A is left hanging downward and rearward with its upper end folded back. To ensure that the sprayed urethane foam h is tightly connected to the upper rear end of the foam base 21, it is preferable to push the urethane foam h downward using a large plastic bag 24 as needed, or to raise and rock the slightly bent-forward upper body backward as indicated by arrow m to return the body to a normal seated position. By returning the upper body backward, the foamed urethane h can be sandwiched and pressed between the main part y and the lumbar support member 26 from the front and back, which is preferable as it spreads the foamed material h up, down, left, and right, contributing to the formation of a lumbar support part 27 that closely conforms to the shape of the back of the lumbar part y and to the connection with the foamed base 21.

[0034] When making a seat 5 without a lumbar support portion 27, it is advisable to carry out the fifth step of removing the belt-like body 25 from the left and right seat pipes 8, 8 after removing the buttocks seat mold 22, as shown by the imaginary line in the middle of the top and bottom of the page in Figure 4. In this case, the lumbar support forming step kk is not carried out, but the plastic bag replacing step ku can be carried out or omitted. That is, in the sixth step k6 carried out after the lumbar support portion fifth step, i.e., setting the foam base 21 contained in the bag-like body in the seating portion 1A of the wheelchair frame 1 from which the seat member 25 has been removed, either the small plastic bag 23 or the large plastic bag 24 can be used as the bag-like body for containing the foam base 21 for only the seating portion 5A.

[0035] After the fourth step including the lumbar support forming step kk, the fifth step k5 is performed as shown in the upper part of Figure 5. The fifth step k5 is a step of removing the loosened belt-like body 25 from the wheelchair frame 1, more specifically from the left and right seat pipes 8, 8, and it is preferable to first remove the large plastic bag 24 containing the foam base 21 with the lumbar support portion 27 from the belt-like body 25. Furthermore, if the wheelchair frame 1 is equipped with lumbar support members 26 by being installed between the left and right rear standing portions 7B, 7B, it is preferable to perform a lumbar support member removing step kp in the fifth step to remove the lumbar support members 26.

[0036] The sixth step k6, which follows the fifth step k5, is a step of placing the foam base 21 with the lumbar support portion 27 housed in the large plastic bag 24 on the left and right seat pipes 8, 8 and setting it in the seating area 1A of the wheelchair frame 1, as shown in the upper part of Fig. 5. In this case, as shown in the lower part of Fig. 5, it is preferable to place the foam base 21 with the lumbar support portion 27 deep inside (deep forward) the large plastic bag 24 with the opening 24A facing backward, so that the opening 24A of the large plastic bag 24 facing backward faces upward. When the foam base 21 with the lumbar support portion 27 is set in the seating area 1A (the state shown in the lower part of Fig. 5), it is preferable that the lower part of the foam base 21 in the large plastic bag 24 hangs down. The foam base 21 is preferably set in the seating area 1A in a regular positioning state over the large plastic bag 24 by placing the left and right side mounting portions 21L, 21R on the corresponding seat pipes 8, 8.

[0037] The seventh step k7, which follows the sixth step k6, may include a bottom-laying step ks, a frame engagement step kf, and a refilling step kh, as shown at the bottom of Fig. 5. The bottom-laying step ks is a step of spraying urethane foam h onto the frame pipes that pass under the foam base 21 of the wheelchair frame 1 inside the large plastic bag 24, i.e., the front connecting pipe 12 and the rear connecting pipe 33, and onto the bottom 21a of the foam base 21, thereby forming the bottom support portion 21A of the foam base 21 with the waist support portion 27. In this case, it is preferable to tear the front end of the large plastic bag 24 shown at the bottom of Fig. 5 to create a tear (not shown), insert a spray gun 31 through the tear, and spray urethane foam h onto the lower part of the bottom 21a and the upper part of the front connecting pipe 12. Although not shown, it is also preferable to partially tear the lower part of the large plastic bag 24, insert the spray gun 31 through the tear, and spray urethane foam h onto the lower part of the bottom 21a and the upper part of the rear connecting pipe 33.

[0038] The bottom placing step ks forms front and rear bottom engaging portions 21f, 21r (see the upper side of FIG. 6) that position and place the bottom support portion 21A on the upper sides of the front and rear connecting pipes 12, 33. The front and rear bottom engaging portions 21f, 21r preferably form a seat base 29 that can support the weight of the user U acting on the foam base 21 (foam base 21 with waist support portion 27) with the front and rear connecting pipes 12, 33. As mentioned above, the upper portion of the large plastic bag 24 is not shown in the lower part of FIG. 5 for simplicity.

[0039] 5, the frame engagement process kf is a process of blowing urethane foam h onto the frame pipe that passes behind the lumbar support section 27 of the wheelchair frame 1 inside the large plastic bag 24, i.e., onto the back connecting pipe 13 and the back surface of the lumbar support section 27, thereby engaging the lumbar support section 27 with the frame. Specifically, urethane foam h is blown onto the back connecting pipe 13 and the back surface of the lumbar support section 27, both of which are located over the large plastic bag 24, to form a frame engagement section 27a (shown by an imaginary line) for the back connecting pipe 13 on the back side of the lumbar support section 27. The frame engagement section 27a made in the frame engagement process kf is preferable because it enables the back connecting pipe 13 to support rearward and downward loads acting on the lumbar support section 27.

[0040] The refilling process kh includes a step (first refilling step) of refilling foamed urethane h into the side support portions 21L, 21R for the left and right seat pipes 8, 8, as shown at the bottom of Figure 5, and a step (second refilling step) of blowing foamed urethane h into the lumbar support portion 27 so that the rear support portion 27b located in front of the upright rear portion 7B of the wheelchair frame 1 has a certain amount of front-to-rear thickness.

[0041] The first refilling step kh will now be described. The side mounting portions 21L, 21R may be formed in the third or fourth steps k3, k4, or may not be formed or may be insufficiently formed. In the latter case, in the seventh step k7, foamed urethane h is sprayed onto the insufficiently formed or unformed side mounting portion 21L (or 21R) to refill it, thereby forming the desired side mounting portions 21L, 21R.

[0042] As shown at the bottom of Figure 5, the second replenishing step kh is a step of blowing urethane foam h into the lumbar support section 27 so that the rear support sections 27b located in front of the rear standing section 7B of the wheelchair frame 1 have a certain amount of front-to-rear thickness. The left and right rear support sections 27b may be formed in the lumbar support forming step kk, or may not be formed or may be insufficiently formed. In the latter case, in the seventh step k7, urethane foam h is blown to refill the insufficiently formed rear support sections 27b or the unformed rear support sections 27b in front of the rear standing section 7B, thereby forming the desired rear support sections 27b in the lumbar support section 27. It is preferable that the rear support sections 27b and the corresponding side placement sections 21L (or 21R) are continuous.

[0043] The upper side of Figure 6 shows the foamed substrate 21 with the waist support portion 27 after the seventh step k7, i.e., the sheet substrate 29, which is a sheet before finishing. In the sheet substrate 29, a front engagement portion 21f that fits from above onto the front connecting pipe 12 and a rear engagement portion 21r that fits from above onto the rear connecting pipe 33 are formed on the bottom support portion 21A. This sheet substrate 29 is a foamed substrate 21 that has rough finishes such as excess urethane foam 30 due to over-blown or recesses. From the standpoints of strength and shape, it is preferable to perform the eighth step k8, in which urethane foam h is supplied to the recesses, or the excess urethane foam 30 is scraped off or polished or sanded to achieve the desired shape, i.e., to shape the sheet 5. In other words, the manufacturing method for the sheet 5 preferably includes the eighth step k8, in which the foamed substrate 21, i.e., the sheet base material 29, that has been subjected to the seventh step k7, is removed from the large plastic bag 24 and then shaped.

[0044] The lower side of Fig. 6 shows the seat (bucket seat) 5 that has been completed through the eighth step k8. The seat 5 in this example has a bottom support portion 21A (see the upper side of Fig. 6) that fits over and engages with the front and rear connecting pipes 12 and 33, left and right side mounting portions 21L and 21R that fit over and engage with the left and right seat pipes 8, left and right rear support portions 27b that engage with the left and right rear standing portions 7B from the front, and a frame engaging portion 27a (see the upper side of Fig. 6) that fits over and engages with the back connecting pipe 13 from the front. Through holes 5c that penetrate laterally to allow seat belts or the like to pass through may be formed in the left and right side mounting portions 21L and 21R.

[0045] The eighth step k8 preferably includes the steps of refilling recesses and insufficient areas with foam material h, scraping or polishing the excess portion 30 to shape the sheet, reinforcing the edges and corners with a reinforcing material such as a fiber material, drilling holes for passing belt members for fixing the sheet to the wheelchair frame 1, finishing such as painting, and other processing steps to achieve the desired appearance. In the sheet 5 shown at the bottom of the page in Figure 6, parts that have the same functions as the sheet 5 shown in Figures 1 and 2 are given the same reference numerals.

[0046] In this way, the seat 5 manufactured by the manufacturing method of the present invention is configured so that the left and right frame portions of the wheelchair frame 1 support the load at three locations: two locations at the front and rear of bottom support portion 21A, which is the lower part of seating portion 5A, and one location at waist support portion 27. In addition, the seat pipes 8, 8 can support a certain amount of vertical load via left and right side rests 21L, 21R, and the upright rear portions 7B, 7B can support a certain amount of rear load via left and right rear support portions 27b, 27b. By having the wheelchair frame 1 support the seat 5 at these seven locations, it is possible to provide a good fit to the user's body while still providing sufficient strength and firm support, which is preferable even for hard sports such as wheelchair basketball.

[0047] [About the effects and effects] Conventionally, custom-made sports wheelchair seats have often been produced using the following manufacturing method: First, a mold is taken of the wheelchair user's buttocks, lower back, or back, and a seat is manufactured using that mold in a shape and size that can be securely attached to the wheelchair frame. The manufactured seat is then installed in the wheelchair and the user takes it for a test run, making fine adjustments as needed, and once the user's approval is obtained, the seat is then finalized.

[0048] The process of fitting the seat to the seating portion of the wheelchair frame properly (corresponding to the seventh process in this invention) requires repeated, painstaking work such as adding and removing material from the seat, which takes time. Therefore, there is often a gap of several days between the day of molding and the day of the test run. Therefore, users have to visit the seat manufacturing site for at least two days, with several days in between. For users, visiting the seat manufacturing site multiple times, separated by several days, is a burden. This can lead to delays in seat manufacturing due to scheduling conflicts, or users tend to avoid made-to-order production due to the hassle.

[0049] According to the manufacturing method of the present invention, when making a seat using a lightweight, moldable foam material, the actual wheelchair frame can be used as a mold for the foam material by blowing the foam material into a bag-shaped body. In other words, the bag-shaped body that receives the foam material can be deformed to fit the shape of the wheelchair frame, so the wheelchair frame, via the bag-shaped body, essentially functions as a mold for the foam material, thereby forming a foam base shaped to fit the wheelchair frame. In the fourth step, the user's buttocks and lower back support are formed directly in the foam base, making it possible to produce a seat that fits the user's buttocks and lower back better. The hardened foam base in the seventh step can be placed on the wheelchair frame, allowing the user to sit on the foam base seat and test ride it.

[0050] In the fourth step, in which a mold of the user's buttocks is taken from the foam base, it is possible to form a portion that engages with the wheelchair frame (for example, a side support portion that rests on the seat pipe). Therefore, the seventh step, in which foam material is blown onto the foam base with the buttocks formed thereon to position it on the wheelchair frame, can be carried out simply and reliably with the foam base actually set in the seating portion of the wheelchair frame. Therefore, the process from taking a mold of the user's buttocks from the foam base (step 4) to the process of positioning the foam base so that it can be mounted on the wheelchair frame (step 7) can be carried out in a short time, dramatically shortening the time required for seat manufacturing compared to conventional methods. For example, it is possible to take a mold of the user's buttocks and test-run the completed seat on the same day.

[0051] In this way, the mold of the user's buttocks and the test run can be performed in a short span of time, such as on the same day, which reduces the labor burden on the user of visiting the manufacturing site and makes it possible to produce a made-to-order wheelchair seat that fits both the user and the wheelchair in an extremely short period of time.As a result, it is possible to provide a wheelchair seat manufacturing method that is devised to easily and quickly produce a made-to-order seat that fits the user well, so that a seat that is more suitable for sports can be realized.

[0052] Since a bag-shaped body is used as the place where the foam material is blown, the blown foam material can be easily moved or pushed into the desired location through the bag-shaped body, and the buttocks seat mold can be taken by simply sitting on the bag-shaped body, so both can be done cleanly without directly touching the foam material, and the blown foam material can be prevented or suppressed from scattering around. Furthermore, as the foam material, foamed urethane is preferred because it has high density, good moldability, and is easily available, and 30x foamed urethane is more preferred.

[0053] It is preferable to use a belt-like body (a part attached to the wheelchair C) stretched across the left and right seat pipes 8, 8 of the wheelchair frame 1 as the seat member 25 on which the small plastic bag 23 and the large plastic bag 24 are placed, so that in the first step k1, a relaxation step k1s can be performed to loosen the tension of the belt-like body 25. Using the belt-like body 25, which is a part attached to the wheelchair C when it is purchased, is preferable because it does not require the preparation of a seat member as a separate, dedicated part, which saves extra time and cost, and it can provide sufficient strength to support the user U when he or she sits down when taking the buttocks seat impression.

[0054] [Another embodiment] (1) The seat 5 may have a seating portion 5A that does not have a lumbar support portion 27. In this case, the steps are changed from those of this embodiment as follows: In the fourth step, the lumbar support forming step kk is not necessary, and the bag-shaped body replacing step ku can also be omitted. In the fifth step, the lumbar support member removing step kp is not necessary. In the seventh step, the frame engaging step kf and the replenishing step kh for the rear support portion 27b are not necessary.

[0055] (2) The seat 5 may have a backrest that extends above the lumbar support portion 27. In this case, it is preferable to form the backrest by blowing the foam material h higher than the lumbar support portion 27 in the lumbar support forming step kk of the fourth step, but other methods of making the backrest are also acceptable.

[0056] (3) If the wheelchair C does not come with a belt-like member 25, a belt-like member from another wheelchair may be temporarily borrowed. Alternatively, a deep dish-like member made of a hard material (metal plate, synthetic resin material, etc.) with an upper surface similar to that of the loosened belt-like member 25 may be prepared and used in place of the sheet member 25, or other means may be used.

[0057] (4) A seat may be made that does not have the left and right side placement portions 21L, 21R or the left and right rear support portions 27b, 27b, as in the seat 5 shown in FIGS.

[0058] (5) As the foam material, in addition to foamed urethane (foamed polyurethane), foamed polyethylene, foamed polystyrene (foamed polystyrene), foamed polypropylene, etc. may also be used. (6) The bag-shaped body may be a vinyl bag, a nylon bag, a paper bag, or the like, in addition to the plastic bags 23 and 24. [Explanation of symbols]

[0059] 1 wheelchair frame 1A Seating area 8 seat pipe 12 Frame pipe, front connecting pipe 13 Frame pipe, rear connecting pipe 21 Foam base material 21A Bottom support 22 Hip type 23 Bags, small plastic bags 24 Bag-shaped body, large plastic bag 25 Sheet material, belt-shaped body 26 Waist support member 27 Waist support U user h Foam material, urethane foam k1~k8 1st~8th process kf bag replacement process kk Waist support forming process ks Bottom-mounting process y lower back

Claims

1. a first step of preparing a wheelchair frame having a seat member for supporting the weight of a user; a second step of placing a bag-shaped body on the sheet member; a third step of blowing a foam material into the bag-shaped body to form a foam base; a fourth step of forming a buttocks seating shape in the foam base by a user sitting on the bag-shaped body while the foam base is in an uncured state; a fifth step of removing the seat member from the wheelchair frame; a sixth step of setting the foam substrate contained in the bag-shaped body in the seating portion of the wheelchair frame from which the seat member has been removed; a seventh step of blowing foam material onto the foam substrate and the wheelchair frame within the bag to position the foam substrate relative to the wheelchair frame; A method for manufacturing a wheelchair seat having the above structure.

2. 2. The method for manufacturing a wheelchair seat according to claim 1, wherein the seat member is a belt-like body stretched across left and right seat pipes of the wheelchair frame, and the first step includes a step of loosening the tension of the belt-like body.

3. The method for manufacturing a wheelchair seat according to claim 1, wherein the foam material is urethane foam.

4. A method for manufacturing a wheelchair seat as described in any one of claims 1 to 3, wherein the fourth step includes a step of forming a lumbar support portion in the foam base by blowing foam material onto a lumbar support member provided on the wheelchair frame and the lumbar portion of the user inside the bag-shaped body while the user is seated on the foam base from above the bag-shaped body.

5. 5. The method for manufacturing a wheelchair seat according to claim 4, wherein the seventh step includes a step of blowing foam material onto a frame pipe that passes behind the lumbar support portion of the wheelchair frame and onto the back surface of the lumbar support portion inside the bag-shaped body, with the lumbar support member removed from the wheelchair frame, to frame engage the lumbar support portion.

6. The method for manufacturing a wheelchair seat according to any one of claims 1 to 3, wherein the seventh step includes a step of blowing foam material onto a frame pipe that passes under the foam base in the wheelchair frame and onto the bottom of the foam base inside the bag-shaped body to form a bottom support portion on the foam base.

7. 4. The method for manufacturing a wheelchair seat according to claim 1, further comprising an eighth step of removing the foamed base material that has been subjected to the seventh step from the bag-shaped body and adjusting its appearance.

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