An embodiment of the present invention relates to a spur gear component, a spur gear, and a spur gear component manufacturing method.
As a method of manufacturing a gear using a fiber material, one described in Patent Literature 1 is known. In this manufacturing method, a band-shaped semi-molded product having a straight tooth shape is molded by molding a band-shaped prepreg. Then, a spur gear molded product is obtained by rolling the band-shaped semi-molded product in a cylindrical shape to prepare a cylindrical semi-molded product, installing the cylindrical semi-molded product in a mold, and performing a molding operation.
Patent Literature 1: Japanese Unexamined Patent Publication No. 2011-25466
Here, in the above-described spur gear component manufacturing method, the band-shaped member of the fiber material of which the width dimension is set to be the same as the size of the spur gear component in the width direction in advance is used. That is, the entire length of the tooth of the spur gear component in the width direction is the same as the entire length of the band-shaped member in the width direction. Here, both end portions of the band-shaped member in the extension direction serve as the cut portions of the fiber material. Thus, the spur gear component described in Patent Literature 1 is in a state in which the cut portions of the fiber material are continuously arranged over the entire length of the tooth in the width direction. In this case, a problem arises in that the strength of the tooth decreases.
An object of the present invention is to provide a spur gear component capable of obtaining a spur gear capable of improving strength, a spur gear capable of improving strength, and a spur gear component manufacturing method capable of obtaining such a spur gear.
A spur gear component according to an embodiment of the present invention is a spur gear component including a plurality of teeth protruding in a radial direction, extending in an axial direction, and arranged at equal pitches in a circumferential direction, the spur gear component including a fiber material having a shape corresponding to an arrangement pattern of the plurality of teeth and wound in a spiral shape around a center axis.
The spur gear component according to an embodiment of the present invention includes the fiber material having a shape corresponding to the arrangement pattern of the plurality of teeth and wound in a spiral shape around the center axis. In this case, since the plurality of teeth are composed of the wound fiber material, the strength of the tooth can be made higher than that of the tooth of the spur gear formed by molding only the resin material. Here, the fiber material is wound in a spiral shape. In this case, a cut portion is formed at a winding starting end portion and a winding finishing end portion of the fiber material, but the fiber material extends continuously without cutting at another orbital portion arranged in parallel in the axial direction. In this way, in the spur gear component, it is possible to prevent a portion in which the cut portion of the fiber material is continuously formed over the entire axial direction, that is, the entire length of the width of the tooth. As described above, the strength of the spur gear can be improved.
In the spur gear component, one end portion and the other end portion of the fiber material in a longitudinal direction may be disposed at different positions in the circumferential direction. One end portion and the other end portion of the fiber material are located at the positions of the cut portions of the fiber material in which the strength of the spur gear component decreases. When one end portion and the other end portion are shifted in the circumferential direction, it is possible to suppress a portion where the strength decreases from being concentrated at a specific position in the circumferential direction.
In the spur gear component, the fiber material may be wound in parallel in an axial direction. In this case, since the fiber material is wound in parallel, the fiber material can easily follow the shape of the mold when molding the arrangement pattern of the teeth.
A spur gear according to an embodiment of the present invention is a spur gear including: a spur gear component that includes a plurality of teeth protruding in a radial direction, extending in an axial direction, and arranged at equal pitches in a circumferential direction; and a base portion formed on an inner peripheral side of the spur gear component, in which the spur gear includes a fiber material having a shape corresponding to an arrangement pattern of the plurality of teeth and wound in a spiral shape around a center axis, and in which the base portion is formed by a resin molded body fixed to the spur gear component.
According to the spur gear according to an embodiment of the present invention, the same action and effect as the above-described spur gear component can be obtained. Further, the base portion is formed by the resin molded body fixed to the spur gear component. In this way, since a portion that does not require strength compared to the portion of the tooth is formed by the resin molded body, the weight of the entire spur gear can be made light.
A spur gear component manufacturing method according to an embodiment of the present invention is a method of manufacturing a spur gear component including a plurality of teeth protruding in a radial direction, extending in an axial direction, and arranged at equal pitches in a circumferential direction, including: forming an annular member by winding a fiber material in a spiral shape around a center axis; and forming a shape of the tooth in the annular member.
According to the spur gear component manufacturing method according to an embodiment of the present invention, the same action and effect as the above-described spur gear component can be obtained.
In the spur gear component manufacturing method, in the forming of the shape of the tooth, an inner peripheral side of the annular member may be supported by an inner peripheral mold and a plurality of outer peripheral molds divided in a circumferential direction may be pressed against the annular member from an outer peripheral side to form the shape of the tooth. In this case, the tooth having a shape corresponding to the shape of the mold can be easily formed on the front surface of the annular member.
According to an embodiment of the present invention, it is possible to provide a spur gear component capable of obtaining a spur gear capable of improving strength, a spur gear capable of improving strength, and a spur gear component manufacturing method capable of obtaining such a spur gear.
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. Additionally, in the drawings, the same or corresponding parts will be denoted by the same reference numerals and redundant description will be omitted.
As illustrated in
The spur gear component 1 is an annular member which includes a plurality of teeth 4. That is, the spur gear component 1 constitutes a ring gear used as a tooth member of the spur gear 3. The tooth 4 of the spur gear component 1 protrudes in the radial direction, extends in the axial direction, and is disposed at a plurality of positions at equal pitches in the circumferential direction. A valley portion 6 which meshes with a mating gear is formed between the tooth 4 and the tooth 4. The plurality of teeth 4 are formed on an outer peripheral surface of the annular member. In this embodiment, the tooth 4 extends straightly in the axial direction. Additionally, the shape of the tooth 4 is not particularly limited. The spur gear component 1 is manufactured by using a fiber material. A method of manufacturing the spur gear component 1 will be described in detail later.
The spur gear component 1 has an arrangement pattern of a plurality of mountain portions 7 and a plurality of valley portions 8 on an inner peripheral surface. The arrangement pattern of the inner peripheral surface corresponds to the arrangement pattern of the teeth 4 and the valley portions 6 of the outer peripheral surface. The spur gear component 1 includes the valley portion 8 formed on the inner peripheral surface at a position in which the tooth 4 is formed on the outer peripheral surface. The spur gear component 1 includes the mountain portion 7 formed on the inner peripheral surface at a position in which the valley portion 6 is formed on the outer peripheral surface. With such a structure, the uniformity of the thickness of the spur gear component 1 is improved and the moldability of the spur gear component 1 is improved.
The base portion 2 is a member that supports the spur gear component 1 and ensures the strength of the spur gear 3. The base portion 2 has a shape in which an area on the inner peripheral side of the spur gear component 1 is buried. The spur gear component 1 is provided along the outer peripheral surface of the base portion 2. A through-hole 2b to which a rotation shaft (not illustrated) of the spur gear 3 is attached is formed at the center position of the base portion 2. The base portion 2 is formed by injection-molding. At the time of manufacturing, the injection-molding is performed while the spur gear component 1 is installed in an injection-molding mold. Accordingly, the spur gear component 1 is fixed to the base portion 2.
Here, as will be described in detail in the manufacturing method to be described later, the spur gear component 1 is manufactured in such a manner that a fiber material 10 is wound in a spiral shape to form an annular member 20 and the shape of the tooth 4 is formed in the annular member 20. Thus, the spur gear component 1 includes the fiber material 10 having a shape corresponding to the arrangement pattern of the plurality of teeth 4 and wound around the center axis CL in a spiral shape. Additionally, in this embodiment, as will be described in detail in the manufacturing method to be described later, the annular member 20 is formed in such a manner that one continuous fiber material 10 is wound around a core member a plurality of times in a spiral shape to form a layer of the fiber material 10 and such spiral winding is performed in a reciprocating manner in the axial direction. Accordingly, the annular member is formed by forming a plurality of layers of the fiber material 10. That is, in this embodiment, a description will be made below such that the spur gear component 1 is composed of one continuous fiber material 10. Additionally, in this specification, the “fiber material” refers to a wire for one fiber. For example, a member called a tow prepreg in which a plurality of fiber materials are twisted and impregnated with a resin is known, but the fiber material of this embodiment corresponds to one wire in a non-twisted state.
As illustrated in
In this embodiment, the fiber material 10 is wound around the center axis in a spiral shape. Thus, the orbital portions adjacent to each other in the axial direction are composed of one continuous fiber material 10. For example, as illustrated in
As illustrated in
Additionally, the fiber material 10 is a continuous fiber in which a fiber is continuous in the longitudinal direction. As the fiber material 10, fibers having high strength and high elastic modulus such as carbon fibers, glass fibers, aramid fibers, silicon carbide fibers, and alumina fibers can be used alone or in combination. From the viewpoint of the strengthening efficiency of the strength of the spur gear component 1 and imparting functions such as dimensional stability, corrosion resistance, slidability, antistatic property, and weight reduction thereto, carbon fibers are most preferable among these fibers.
Further, the spur gear component 1 contains a resin for maintaining the shape of the fiber material 10 formed in a desired shape. The resin is contained in the entire spur gear component 1 and hardens the fiber material 10 while the arrangement pattern of the teeth 4 is formed. As such a resin, for example, a thermoplastic resin is adopted. Although the thermoplastic resin is selected from the required functions of the spur gear component 1, nylon, polyester, polypropylene, polycarbonate, ABS, polyphenylene oxide, polyphenylene sulfide, their polymer alloys, and the like are used in general and particularly when strength or heat resistance is required, polyetherketone, polyetheretherketone, polyetherketoneketone, polyetherimide, polyethersulfone, and the like are used.
Next, a method of manufacturing the spur gear 3 according to this embodiment will be described with reference to
Step S10 is a step of forming the annular member 20 by winding the fiber material 10. In Step S10, the annular member 20 illustrated in
The winding device 25 includes a columnar core portion. The core portion has an outer peripheral length corresponding to the circumferential length of the inner peripheral edge portion of the annular member 20. Additionally, a pair of regulation plates (not illustrated) which faces each other while being separated from each other by the size of the annular member 20 in the axial direction may be provided in the core portion. At the time of winding, the fiber material 10 is wound in an area between the pair of regulation plates. The winding device 25 fixes the starting end portion of the fiber material 10 to the vicinity of the outer periphery of the core portion 26 and rotates the core portion 26. Additionally, a feeding device (not illustrated) sends the fiber material 10 toward the winding device 25. Accordingly, the winding device 25 winds the fiber material 10 between the regulation plates over a plurality of turns. Additionally, the winding device 25 forms a layer in which the plurality of fiber materials 10 are arranged in the axial direction and forms a plurality of the layers in the radial direction to form the annular member 20.
Additionally, a thermoplastic resin is applied to the annular member 20 before performing the subsequent Step S20. Additionally, a timing at which the thermoplastic resin is applied is not particularly limited and the thermoplastic resin may be applied while winding the fiber material 10, the thermoplastic resin may be applied in advance to the fiber material 10 which will be wound, or the thermoplastic resin may be applied to the annular member 20 which is completely wound.
Step S20 is a step of forming the shape of the tooth 4 in the annular member 20. In Step S20, the molding device 40 illustrated in
The molding device 40 includes a plurality of outer peripheral molds 41 which are disposed on the outer peripheral side of the set annular member 20 and a plurality of inner peripheral molds 42 which are disposed on the inner peripheral side thereof. The outer peripheral mold 41 is a mold that molds the shapes of the tooth 4 and the valley portion 6 on the outer peripheral side of the spur gear component 1. The plurality of outer peripheral molds 41 are disposed at equal pitches in the circumferential direction along the outer peripheral surface of the annular member 20. The inner peripheral mold 42 is a mold that molds the shapes of the mountain portion 7 and the valley portion 8 on the inner peripheral side of the spur gear component 1. The plurality of inner peripheral molds 42 are disposed at equal pitches in the circumferential direction along the inner peripheral surface of the annular member 20.
As illustrated in
In Step S20, the outer peripheral mold 41 and the inner peripheral mold 42 are pressed against the annular member 20 in the radial direction in a heated state to form the shape of the tooth 4. Specifically, as illustrated in
Step S30 is a step of molding the base portion 2 in the spur gear component 1. In Step S30, insert-molding is performed by using the mold 49. As illustrated in
Next, the action and effect of the spur gear component 1, the spur gear 3, and the method of manufacturing the spur gear component 1 according to this embodiment will be described.
The spur gear component 1 according to this embodiment includes the fiber material 10 having a shape corresponding to the arrangement pattern of the plurality of teeth 4 and wound in a spiral shape around the center axis. In this case, since the plurality of teeth 4 is composed of the wound fiber material 10, the strength of the tooth 4 can be made higher than that of the tooth of the spur gear formed by molding only the resin material.
For example, when the spur gear component 1 is formed by one continuous fiber material 10, a cut portion (an end portion 10a) of the fiber material 10 illustrated in
In contrast, in the spur gear component 1 according to this embodiment, the fiber material 10 is wound in a spiral shape. In this case, the cut portion is formed at the winding starting end portion and the winding finishing end portion of the fiber material, but the fiber material 10 extends continuously without cutting in another orbital portion arranged in parallel in the axial direction (for example, see FIG. 2(b)). In this way, it is possible to prevent a portion in which the cut portion of the fiber material 10 is continuous in the entire axial direction, that is, the entire length of the width of the tooth in the spur gear component 1. As described above, the strength of the spur gear 3 can be improved.
In the spur gear component 1, one end portion 10a and the other end portion 10b of the fiber material 10 in the longitudinal direction are disposed at different positions in the circumferential direction (see
In the spur gear component 1, the fiber material 10 is wound in parallel in the axial direction. In this case, since the fiber material 10 is wound in parallel, the fiber material 10 can easily follow the shape of the mold when molding the arrangement pattern of the teeth 4.
The spur gear 3 according to this embodiment is the spur gear 3 including the spur gear component 1 which includes a plurality of teeth protruding in the radial direction, extending in the axial direction, and arranged equal pitches in the circumferential direction and the base portion 2 which is formed on the inner peripheral side of the spur gear component 1, the spur gear 3 includes the fiber material 10 having a shape corresponding to the arrangement pattern of the plurality of teeth 4 and wound in a spiral shape around the center axis and the base portion 2 is formed by the resin molded body fixed to the spur gear component 1.
According to the spur gear 3 according to this embodiment, the same action and effect as the spur gear component 1 can be obtained. Further, the base portion 2 is formed by the resin molded body fixed to the spur gear component 1. In this way, since a portion that does not require strength compared to the portion of the tooth 4 is formed by the resin molded body, the weight of the entire spur gear 3 can be made light.
A method of manufacturing the spur gear component 1 according to this embodiment is a method of manufacturing the spur gear component 1 including the plurality of teeth 4 protruding in the radial direction, extending in the axial direction, and arranged at equal pitches in the circumferential direction and includes a step of forming the annular member 20 by winding the fiber material 10 in a spiral shape around the center axis and a step of forming the shape of the tooth 4 in the annular member 20.
According to the method of manufacturing the spur gear component 1 according to this embodiment, the same action and effect as the spur gear component 1 can be obtained.
In the method of manufacturing the spur gear component 1, in the step of forming the shape of the tooth 4, the inner peripheral side of the annular member 20 may be supported by the inner peripheral mold 42 and the plurality of outer peripheral molds 41 divided in the circumferential direction may be pressed against the annular member 20 from the outer peripheral side to form the shape of the tooth 4. In this case, the tooth 4 having a shape corresponding to the shapes of the molds 41 and 42 can be easily formed on the front surface of the annular member 20.
The present invention is not limited to the above-described embodiment.
For example, in the above-described embodiment, the annular member 20 was formed by winding one continuous fiber material 10 in a spiral shape when forming the annular member 20. Instead, when the fiber material 10 runs out while winding the fiber material 10 in order to form the annular member 20, the winding may be resumed by setting a new fiber material 10. Further, the annular member 20 may be formed by winding the plurality of fiber materials 10 in a bundle. A state in which the plurality of fiber materials 10 are bundled may be, for example, a tow prepreg.
Further, a band-shaped member 50 illustrated in
Since the end portions 50a and 50b of the band-shaped member 50 in the winding direction correspond to the cut portions of the fiber material 10, the end portions serve as portions that affect the strength of the tooth 4. In contrast, the plurality of band-shaped members 50 are disposed within the width dimension L2 of the tooth 4 of the spur gear component 1. In the end portions 50a and 50b corresponding to the cut portions and other portions arranged in parallel in the axial direction, the band-shaped member 50 (that is, the fiber material 10) extends continuously without cutting. For example, as illustrated in
1: spur gear component, 2: base portion, 3: spur gear, 4: tooth, 10: fiber material, 20: annular member, 41: outer peripheral mold, 42: inner peripheral mold.
Number | Date | Country | Kind |
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2018-095677 | May 2018 | JP | national |
Filing Document | Filing Date | Country | Kind |
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PCT/JP2019/019372 | 5/15/2019 | WO | 00 |