JP2022119507A - Hand rim for wheelchair and method for manufacturing the same - Google Patents

Abstract

To propose a hand rim for a wheelchair in which the joint strength with the wheel of the wheelchair can be improved, and the wheelchair can stably be used over a long term, and its manufacturing method.SOLUTION: A hand rim for a wheelchair includes a rim body 2 made by fiber reinforced plastic, and multiple mounting members 11 disposed at intervals in the circumferential direction of the rim body 2. The mounting member 11 includes an embedded part 13 embedded between layers of the reinforcing fibers of the fiber reinforced plastic for configuring the rim body 2, and a protrusion 12 protruded from the rim body 2. The hand rim 1 having such a configuration is improved in the joint strength between the rim body 2 and the mounting member 11. Also, as a manufacturing method of such hand rim 1, there are included a forming step of laminating the reinforcing fibers and a curing step of curing matrix resin. In the forming step, the embedded part 13 of the mounting member 11 is arranged between the layers of the reinforcing fibers.SELECTED DRAWING: Figure 2

Description

TECHNICAL FIELD The present invention relates to a handrim for a wheelchair and a method for manufacturing the handrim.

The wheelchair has a hand rim attached to a driving wheel that is operated by a user to rotate the driving wheel. As such a hand rim, Patent Document 1, for example, proposes a hand rim made of fiber-reinforced plastic. Since such a hand rim having a conventional configuration is molded from fiber-reinforced plastic made of reinforcing fibers having excellent specific strength and specific modulus, it is possible to achieve both weight reduction and mechanical properties (strength and rigidity).

JP 2007-267905 A

By the way, the conventional hand rim described above is attached to the wheel by screwing a shaft member projecting from the wheel (driving wheel) into an insert nut attached to the hand rim. Here, the insert nut is to be fixed by being inserted into a nut mounting hole formed in the hand rim after molding the hand rim, and is usually fixed to the hand rim with an adhesive.
In such a conventional configuration, when the hand rim is operated by the user, the shaft member and the insert nut that connect the hand rim and the wheel are likely to be subjected to a load, so that it can be used for a relatively long period of time or when a strong load acts instantaneously. There was a risk that the insert nut would come off from the hand rim due to such things as. Therefore, there has been a demand for a structure capable of improving the joint strength between the handrim and the wheel.

An object of the present invention is to provide a hand rim for a wheelchair which can improve the joint strength with the wheel of the wheelchair and which enables the wheelchair to be used stably over a long period of time, and a method for manufacturing the hand rim.

A first aspect of the present invention is a rim body molded in a hollow shape from a fiber-reinforced plastic made of reinforcing fibers and a matrix resin, and a plurality of mounting members provided on the rim body at predetermined intervals in the circumferential direction. A hand rim for a wheelchair that is attached to a wheel of a wheelchair via the attachment member, wherein the rim body is formed by laminating reinforcing fibers constituting the fiber-reinforced plastic in a thickness direction, and The mounting member includes an embedded portion embedded between layers of reinforcing fibers forming the rim main body, and a protruding portion protruding from the rim main body and fixed to the wheel of the wheelchair via a predetermined fixing means. and a hand rim for a wheelchair.

Here, carbon fiber, glass fiber, aramid fiber, etc. can be applied as the reinforcing fiber. Thermosetting resins such as epoxy resins and phenol resins are preferably used as the matrix resin, but thermoplastic resins such as polyamide resins can also be used.
The mounting member can be made of, for example, metal such as aluminum alloy, stainless steel, and steel, plastic, or fiber-reinforced plastic. Bolts and screws are preferably used as fastening means, but welding can also be used if the mounting member is made of metal.

In such a configuration, since the embedded portion of the mounting member fixed to the wheel is embedded between the layers of the reinforcing fibers forming the rim body and integrated with the rim body, the mounting member can be attached to the rim body. Bonding strength with members is extremely high. Therefore, the hand rim of the present invention, in a state where it is attached to the wheel of the wheelchair, has improved resistance to the load applied during use of the wheelchair, and can suppress breakage due to use over a relatively long period of time or the action of a strong load. Therefore, according to the configuration of the present invention, the wheelchair can be used stably over a relatively long period of time.

A second invention of the present invention is a manufacturing method for manufacturing a hand rim for a wheelchair according to the first invention described above, wherein the original body of the rim body is formed by laminating the reinforcing fibers in the thickness direction. and a curing step of curing the matrix resin combined with the reinforcing fibers constituting the original body of the hand rim. A method for manufacturing a hand rim for a wheelchair, characterized in that a member arranging step of arranging the embedded portions of the mounting members at predetermined intervals is executed.

Here, the forming process includes a method of laminating a prepreg in which reinforcing fibers are impregnated with a matrix resin, a method of laminating a reinforcing fiber base material (such as a woven fabric), and a method of arranging and winding bundles of reinforcing fibers and laminating them. It is also possible to apply any of the above. Moreover, as the curing step, it is possible to apply any of a method using an autoclave, a method using a mold, a method using a vacuum, and the like.

In such a manufacturing method, in the forming step of laminating the reinforcing fibers, the embedded portion of the mounting member is arranged between the layers of the reinforcing fibers to form the original body of the rim main body, and then the matrix resin is cured in the curing step. Since the mounting member is formed by pressing and forming, the mounting member can be integrally formed with the rim body. Therefore, according to this manufacturing method, it is possible to easily manufacture the hand rim of the first invention in which the bonding strength between the rim body and the mounting member is extremely high.

As described above, the hand rim for a wheelchair according to the present invention exhibits extremely high joint strength between the rim body and the mounting member, so that the rim body and the attachment member are not easily damaged by long-term use or momentary application of a strong load. Damage to the joint with the mounting member can be suppressed. Therefore, according to the wheelchair to which the hand rim for the wheelchair of the present invention is attached, it can be used stably over a relatively long period of time.

The wheelchair hand rim manufacturing method of the present invention can easily and stably manufacture the above-described wheelchair hand rim.

Fig. 2 is a perspective view showing the mounting state of the hand rim 1 of the embodiment and the wheel 51 of the wheelchair. FIG. 4 is a vertical cross-sectional view showing how the hand rim 1 and the wheel 51 are attached. 4 is a perspective view in which the hand rim 1 and the wheel 51 are separated; FIG. 1 is a perspective view of a hand rim 1; FIG. It is the (A) front view of the attachment member 11, (B) a side view, and (C) a perspective view. FIG. 4 is an explanatory diagram showing a manufacturing process of the hand rim 1; It is (A) a front view, (B) a side view, and (C) a perspective view of the mounting member 41 of another example.

An embodiment according to the present invention will be described with reference to the accompanying drawings.
A wheelchair (not shown) is provided with a hand rim 1 that can be rotated by the user when the wheelchair is self-propelled. As shown in FIGS. 1 to 3, the hand rim 1 is attached to a wheel 51 that constitutes a drive wheel, and is rotated to rotate the drive wheel. The tire attached to the wheel 51 and the spokes forming the wheel 51 can be the same as the conventional ones, so illustration and description thereof will be omitted.

The wheel 51 includes a pair of left and right flange portions 52 that support the sidewalls of the tire, and a rim recess portion 53 that continues between the flange portions 52 and 52. A plurality of rim-side mounting pieces 55 for mounting 1 are arranged at predetermined intervals in the circumferential direction. The rim-side mounting piece 55 has a substantially plate-like shape and includes a rim contact portion that contacts the inner peripheral surface of the rim recess 53 and a projecting portion that extends outward from the rim contact portion. A mounting hole (not shown) is formed through the rim contact portion, and a mounting hole 56 is formed through the projecting portion. The rim-side mounting piece 55 is fixed to the rim recess 53 by means of a mounting bolt 58 inserted through a mounting hole of the rim contact portion and a through hole (not shown) penetrating the rim recess 53 . ing.

On the other hand, the hand rim 1 includes an annular rim body 2 and a plurality of mounting members 11 fixed to the rim body 2 at predetermined intervals in the circumferential direction. Here, the mounting members 11 are mounted on the rim-side mounting pieces 55 arranged on the wheel 51 , and the same number of mounting members 11 are provided at circumferential positions corresponding to the rim-side mounting pieces 55 .

A rim body 2 of the hand rim 1 is hollow and made of carbon fiber reinforced plastic (hereinafter referred to as CFRP), which is a composite of carbon fiber and matrix resin. As will be described later, the rim body 2 of the present embodiment is formed by laminating a predetermined number of fabric prepregs, which are carbon fiber fabrics impregnated with a matrix resin, and is formed thin and hollow. . In this embodiment, an epoxy resin (thermosetting resin) is used as the matrix resin. Here, carbon fiber corresponds to the reinforcing fiber according to the present invention.

The rim body 2, as shown in FIGS. 3 is wider than the inner annular portion 4 in the axial direction orthogonal to the radial direction. While the axial outer surface of the outer ring portion 3 and the axial outer surface of the inner ring portion 4 are uniformly joined together, the axial inner surface of the outer ring portion 3 and the axial direction of the inner ring portion 4 The inner surface is connected through the inclined peripheral surface portion 5 . According to the rim body 2 configured by the outer ring portion 3 and the inner ring portion 4, the user can easily grasp and operate the rim body 2. As shown in FIG.

As shown in FIG. 5, the mounting member 11 is formed by bending a flat plate-like rectangular piece. It is composed of an embedded portion 13 bent from the edge. An elongated insertion hole 14 is formed through the projecting portion 12, and a circular hole-shaped resin insertion portion 15 is formed through the embedded portion 13 in the plate thickness direction.

The embedded portion 13 of the mounting member 11 is embedded in the inclined peripheral surface portion 5 of the rim body 2 and integrated with the rim body 2 as shown in FIG. That is, the rim body 2 is formed by laminating woven fabric prepregs as described above, and during molding, the embedded portion 13 of the mounting member 11 is embedded between the layers of the woven fabric prepreg, and the matrix resin of the prepreg is formed. is cured, the mounting member 11 is integrally molded. The mounting member 11 has the embedded portion 13 embedded in the rim body 2 , and the projecting portion 12 projects axially from the rim body 2 . Here, since the mounting member 11 is in a state where the matrix resin enters the resin fitting portion 15 of the embedding portion 13 and hardens, an anchoring effect is generated and the mounting member 11 is firmly integrated with the rim body 2 .

The hand rim 1 of this embodiment is attached to the wheel 51 by fixing the attachment members 11 to the rim-side attachment pieces 55 of the wheel 51, as shown in FIG. More specifically, the protruding portions 12 of the mounting members 11 arranged on the rim body 2 and the rim-side mounting pieces 55 of the wheel 51 are opposed to each other, and the insertion holes 14 of the protruding portions 12 are aligned. The mounting holes 56 of the rim-side mounting pieces 55 are overlapped. In this state, the mounting bolt 21 is inserted through the insertion hole 14 and the mounting hole 56, and the mounting bolt 21 and the mounting nut 22 are screwed together. 11 and the rim-side attachment piece 55 are fixed. The hand rim 1 is attached to the wheel 51 by fixing the attachment members 11 of the hand rim 1 to the rim-side attachment pieces 55 of the wheel 51 in this manner.
Incidentally, in this embodiment, the mounting bolt 21 and the mounting nut 22 correspond to the fastening means according to the present invention.

Next, a method for manufacturing the hand rim 1 of this embodiment described above will be described.
In this embodiment, as a method of manufacturing the hand rim 1, an internal pressure molding method known as a method of manufacturing CFRP products is used.

In the manufacturing process for manufacturing the hand rim 1, as shown in FIG. 6, the fabric prepreg is laminated on an internal pressure imparting body such as a thermoplastic resin tube to form a preform; A setting step of setting the original body in the cavity of the mold, a curing step of injecting high-pressure gas into the internal pressure applying body of the original body and heating the mold, and a molded product taken out of the mold. A finishing process for adjusting the surface shape is sequentially performed. Each of these steps is described below.

In the forming step, the original body is formed by stacking and pasting the fabric prepreg cut into a predetermined shape on the outer surface of the internal pressure applying body. Then, in the forming process of the present embodiment, the attachment member 11 is arranged in a state in which a predetermined number of woven fabric prepregs are adhered. At this time, the mounting member 11 is placed with its embedded portion 13 placed on the surface of the fabric prepreg attached to the internal pressure applying body. After that, a predetermined number of woven prepregs are laminated and attached to cover the embedded portion 13 of the mounting member 11 with the prepregs. Here, the positions at which the mounting member 11 is arranged are the radial position at which the embedded portion 13 of the mounting member 11 is embedded in the inclined peripheral surface portion 5 of the hand rim 1 and the circumferential position at a predetermined interval in the circumferential direction. determined by The protruding portion 12 of each mounting member 11 protrudes from the surface of the original body formed in this forming process. The process of arranging the embedded portion 13 of the mounting member 11 during lamination of the woven fabric prepregs corresponds to the member arranging process according to the present invention.

In the setting step, the original body formed in the forming step is set in the cavity of the mold. Here, the mold has a cavity formed in the external form of the hand rim 1, and furthermore, this cavity is provided with a fitting into which the projecting portion 12 of each mounting member 11 projecting from the original body can be fitted. A hole is formed. In the setting step, the original body is set in the cavity by fitting the projecting portions 12 of the mounting members 11 of the original body into the fitting holes of the cavity.

In the curing step, as described above, gas is injected at a predetermined pressure into the internal pressure applying body of the original body set in the cavity. Then, the mold is heated and held at a predetermined temperature. In this curing step, the matrix resin of the prepreg that constitutes the original body enters into the resin fitting portion 15 of each mounting member 11 and is cured. Here, the curing conditions such as the pressure of the gas injected into the internal pressure applying body, the heating temperature of the mold, and the heating time are determined by the specifications of the woven fabric prepreg (carbon fiber and matrix resin basis weight) and the number of woven prepreg layers (hand rim 1 thickness), and the like.

In the finishing process, the surface is adjusted by removing burrs from the molded product taken out of the mold. Thus, the hand rim 1 of this embodiment is molded.

In the hand rim 1 of this embodiment, as described above, the embedded portion 13 of the mounting member 11 for mounting to the wheel 51 is embedded in the rim body 2 and integrally molded with the rim body 2. The bonding strength between the mounting member 11 and the rim body 2 is extremely high. In particular, since the matrix resin forming the rim body 2 enters the resin fitting portion 15 of the mounting member 11 and hardens, the mounting member 11 can be joined to the rim body 2 more firmly due to its anchoring effect. For this reason, the wheelchair can exhibit high resistance to the load applied during use, and the joint between the mounting member 11 and the rim body 2 will not be damaged due to use over a relatively long period of time or the action of a strong load. can be suppressed. That is, since the hand rim 1 of the present embodiment is made of CFRP, which has excellent specific strength and specific modulus, it is possible to reduce the weight while maintaining the desired strength and rigidity. It can be suppressed.

As described above, the manufacturing method of the present embodiment is a method of manufacturing the hand rim 1 by the internal pressure molding method, in which the fabric prepreg is laminated on the internal pressure imparting body to form the original body (preform). In the process, the mounting member 11 is arranged and embedded between the overlapping fabric prepregs, and then the setting process, the curing process, and the finishing process are sequentially performed to form the hand rim 1 of the present embodiment described above. In the hand rim 1 manufactured in this manner, the embedded portion 13 of the mounting member 11 is embedded in the rim body 2, and the mounting member 11 and the rim body 2 are joined extremely firmly. Therefore, according to the manufacturing method of the present embodiment, it is possible to stably manufacture the hand rim 1 of the present embodiment, which exhibits the above-described effect of preventing the joint portion between the mounting member 11 and the rim body 2 from being damaged.

The present invention is not limited to the above-described embodiments, and can be modified as appropriate without departing from the scope of the present invention.
For example, the rim body 2 of the embodiment has a configuration including the outer ring portion 3 and the inner ring portion 4, but the configuration of the rim body 2 is not limited to this, and the shape of the rim body 2 can be changed as appropriate. For example, it may have an annular shape with a cylindrical cross section, or it may have a substantially beaded shape in which a diameter-enlarged portion and a diameter-reduced portion are repeatedly coupled.
In the embodiment, the mounting member 11 of the hand rim 1 is fixed to the rim-side mounting piece 55 of the wheel 51 . It may be a configuration in which it is directly fixed with a bolt or the like.
Also, the number of mounting members 11 provided on the hand rim 1 can be changed as appropriate.
In the embodiment, the hand rim 1 is made by laminating woven fabric prepregs, but the present invention is not limited to this. good. Even when such a unidirectional prepreg is used, it can be molded by the internal pressure molding method in the same manner as in the examples.
In addition, although prepreg was used to manufacture the hand rim 1 in the embodiment, the present invention is not limited to this. It is also possible to use an RTM molding method in which a matrix resin is injected into a mold and hardened by laminating a material). Alternatively, it is also possible to use a filament winding method in which a bundle of carbon fibers is wound. In any of these manufacturing methods, the hand rim 1 similar to that of the present embodiment can be manufactured by arranging the mounting member 11 at a predetermined position during lamination of the carbon fibers.
In this embodiment, carbon fiber is used as the reinforcing fiber constituting the hand rim, but the present invention is not limited to this, and it is also possible to use glass fiber or aramid fiber. Furthermore, in the embodiment, the configuration is such that epoxy resin is used as the matrix resin, but it is also possible to use phenol resin (thermosetting resin) or polyamide resin (thermoplastic resin).

Moreover, the shape of the mounting member 11 can be appropriately changed as long as the mounting member 11 includes the embedded portion 13 and the projecting portion 12 . Furthermore, the shape of the resin fitting portion 15 of the embedded portion 13 can be changed as appropriate. For example, in the embodiment, a circular hole penetrating through the embedded portion 13 in the plate thickness direction is used, but the hole is not limited to this, and may be a hole of another shape (for example, square). Furthermore, the resin fitting portion may be formed by notching the side edge of the embedded portion 13, or may be recessed in the plate thickness direction on at least one of the front and back sides of the embedded portion 13. FIG. Furthermore, it is also possible that the embedded portion 13 is not formed with a resin fitting portion.
Here, another specific mounting member 41 is shown in FIG. The mounting member 41 has resin inserting portions 45, 45 which are notched in a semicircular shape on both sides of the embedded portion 13, respectively. Even in such a configuration, the matrix resin of the prepreg enters the inside of the resin fitting portions 45 of the embedded portion 13 and hardens. strongly integrated. The attachment member 41 of another example has notch-shaped resin insertion portions 45, 45 instead of the circular hole-shaped resin insertion portion 15 formed through the attachment member 11 of the above-described embodiment. , and other than this, it is the same as the embodiment, so the same components are denoted by the same reference numerals, and the description thereof is omitted.

REFERENCE SIGNS LIST 1 hand rim 2 rim body 3 outer ring portion 4 inner ring portion 5 inclined peripheral surface portion 11 mounting member 12 projecting portion 13 embedded portion 14 insertion hole 15 resin fitting portion 21 mounting bolt (fixing means)
22 Mounting nut (fixing means)
41 mounting member 45 resin fitting portion 51 wheel 52 flange portion 53 rim concave portion 55 rim side mounting piece 56 mounting hole 58 mounting bolt

Claims (2)

a hollow rim body molded from fiber-reinforced plastic comprising reinforcing fibers and a matrix resin;
A hand rim for a wheelchair, comprising a plurality of attachment members provided on the rim body at predetermined intervals in a circumferential direction, and attached to a wheel of the wheelchair via the attachment members,
The rim body is formed by laminating reinforcing fibers constituting the fiber-reinforced plastic in a thickness direction,
The mounting member is
an embedded portion embedded between layers of reinforcing fibers forming the rim body;
A hand rim for a wheelchair, comprising: a projecting portion projecting from the rim body and fastened to the wheel of the wheelchair via a predetermined fastening means. A manufacturing method for manufacturing a hand rim for a wheelchair according to claim 1,
a forming step of forming the original body of the rim body by laminating the reinforcing fibers in the thickness direction;
a curing step of curing the matrix resin combined with the reinforcing fibers constituting the original body of the hand rim,
Manufacture of a hand rim for a wheelchair, wherein in the forming step, a member arranging step of arranging the embedded portion of the mounting member at a predetermined interval in the circumferential direction between layers of reinforcing fibers laminated in the thickness direction is executed. Method.

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