Gear Manufacturing Equipment

Abstract

To appropriately control an arrangement and direction of reinforcing fibers contained in a resin gear.SOLUTION: There is provided a gear manufacturing device 1 for manufacturing a gear 100 by using resin containing reinforcing fibers having electrostatic properties or magnetism, comprising: a mold 20 in which a molten resin containing reinforcing fibers is filled; and an arrangement adjusting mechanism 24 that generates an electric field or a magnetic field and adjusts an arrangement of the reinforcing fibers in the molten resin in the mold 20. The magnetic field may be a rotating magnetic field, and the electric or magnetic field may be adjustable in strength. The arrangement adjusting mechanism may apply a higher electric field or magnetic field to a tip of the gear than to a root of the gear.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a gear manufacturing apparatus. [Background technology]

[0002] In recent years, gears made of resin have come to be used more and more due to the demand for lighter weight. In order to increase the strength of such plastic gears, it has been proposed to blend reinforcing fibers into the base resin and to align the fiber direction of the reinforcing fibers uniformly along the meshing surfaces of each tooth (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-218994 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the above gear attempts to control the arrangement of the reinforcing fibers by the flow of a base resin material mixed with reinforcing fibers when filling a cavity formed in a resin molding die, and so was poorly feasible and difficult to reproduce.

[0005] An object of the present invention is to provide a gear manufacturing apparatus that can effectively control the arrangement of reinforcing fibers. [Means for solving the problem]

[0006] The present invention relates to A gear manufacturing apparatus for manufacturing gears using a resin containing electrostatically or magnetically reinforcing fibers, A mold into which the molten resin containing the reinforcing fibers is filled; A placement adjustment mechanism that generates an electric field or a magnetic field and adjusts the placement of reinforcing fibers in the molten resin in the mold; Equipped with 、 The arrangement adjustment mechanism arranges the reinforcing fibers so that more of the reinforcing fibers are distributed at the tooth tip portion than at the tooth base portion. It is a gear manufacturing device. In addition, another aspect of the present invention is A gear manufacturing apparatus for manufacturing gears using a resin containing electrostatically or magnetically reinforcing fibers, A mold into which the molten resin containing the reinforcing fibers is filled; A placement adjustment mechanism that generates an electric field or a magnetic field and adjusts the placement of reinforcing fibers in the molten resin in the mold; Equipped with The arrangement adjustment mechanism generates a magnetic field to the reinforcing fibers filled in the mold and having magnetism, The arrangement adjustment mechanism is a gear manufacturing device that generates a rotating magnetic field. Furthermore, still another aspect of the present invention is A gear manufacturing apparatus for manufacturing gears using a resin containing electrostatically or magnetically reinforcing fibers, A mold into which the molten resin containing the reinforcing fibers is filled; A placement adjustment mechanism that generates an electric field or a magnetic field and adjusts the placement of reinforcing fibers in the molten resin in the mold; Equipped with The arrangement adjustment mechanism is a gear manufacturing device in which a stronger electric field or stronger magnetic field is input to an area where the reinforcing fibers are arranged at a higher density than to an area where the reinforcing fibers are arranged at a lower density. Effect of the Invention

[0007] According to the present invention, it is possible to effectively control the arrangement of reinforcing fibers. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a side view of a gear manufacturing apparatus according to a first embodiment. [Diagram 2] FIG. 2(A) is a perspective view showing the positional relationship between a gear formed in a cavity of a mold and a placement adjustment mechanism provided in the mold, and FIG. 2(B) is an axial cross-sectional view taken along the central axis of the gear in the cavity. [Diagram 3] FIG. 11 is an axial cross-sectional view taken along the central axis of a gear when permanent magnets are arranged on both sides of the gear. [Figure 4] FIG. 11 is an axial cross-sectional view taken along the central axis of a gear when electromagnets are arranged on both sides of the gear. [Diagram 5] 11 is a partial side view of a position adjustment mechanism according to a second embodiment, as viewed from an axial direction. FIG. [Figure 6] FIG. 6(A) is a partial side view of a position adjustment mechanism according to the third embodiment as viewed from the axial direction, and FIG. 6(B) is a diagram showing the waveform of an alternating current that is applied to four electromagnets by a current-carrying unit. [Figure 7] FIG. 7(A) is a perspective view of a position adjustment mechanism according to a fourth embodiment, and FIG. 7(B) is an axial cross-sectional view. [Figure 8] 13 is a cross-sectional view perpendicular to the axis of a mold provided with a placement adjustment mechanism according to a fifth embodiment. FIG. [Figure 9] 13 is a cross-sectional view perpendicular to the axis of a mold provided with a placement adjustment mechanism according to a sixth embodiment. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] [Embodiment 1] A first embodiment of the present invention will be described in detail below with reference to the drawings. In the first embodiment, a gear manufacturing apparatus 1 for manufacturing a gear 100 in which reinforcing fibers (hereinafter referred to as reinforcing fibers) are contained in a base material of a resin such as an engineering plastic is illustrated.

[0010] Examples of the resin base material of the gear 100 include engineering plastics (general-purpose engineering plastics) such as polyamide (PA), polycarbonate (PC), polyacetal (POM), modified polyphenylene ether (m-PPE), polybutylene terephthalate (PBT), and super engineering plastics (special engineering plastics) such as polyether ether ketone (PEEK), polyamide imide (PAI), polyphenylene sulfide (PPS), polytetrafluoroethylene (PTFE), aromatic polyamide (PPA), liquid crystal polymer (LCP), polysulfone (PSU), polyether sulfone (PES), polyether imide (PEI), polyarylate (PAR), thermoplastic polyimide (TPI), etc. However, the resin base material is not limited to these and can be changed as appropriate.

[0011] Examples of the reinforcing fibers include glass fibers, aramid fibers, polyethylene fibers, Zylon fibers, boron fibers, carbon fibers, etc. However, the reinforcing fibers are not limited to these and can be changed as appropriate. In addition, a specific material may be added to the reinforcing fibers.

[0012] The above-mentioned gear 100 has, for example, a tooth tip 120 containing more reinforcing fibers than a tooth base 110, and further has a fiber direction of the reinforcing fibers aligned with a meshing surface 121 of the tooth tip 120.

[0013] [Outline of gear manufacturing equipment] 1 is a side view of a gear manufacturing apparatus 1. The gear manufacturing apparatus 1 has a basic structure of an injection molding apparatus. The gear manufacturing apparatus 1 includes a gear mold 20, a bed 11 that supports the entire apparatus, a mold clamping device 30 provided at one end (left side in the figure) on the bed 11, and an injection device 40 provided at the other end (right side in the figure) on the bed 11.

[0014] The mold clamping device 30 includes a pair of opposing wall portions 31, 32 fixed to the bed 11, four tie bars 33 connecting the pair of opposing wall portions 31, 32, a movable plate 34 slidably supported on each tie bar 33, and a fluid pressure cylinder 35 for moving the movable plate 34 back and forth along each tie bar 33.

[0015] The mold 20 is composed of a pair of molds 21, 22, mold 21 is held by a movable plate 34, and mold 22 is held by an opposing wall portion 32. Each of the molds 21, 22 has a recess formed on the opposing surface thereof that constitutes a cavity 23 for forming the gear 100. The mold 20 is also provided with an arrangement adjustment mechanism 24 that generates a magnetic field to adjust the arrangement of the reinforcing fibers in the molten resin inside the mold 20. The mold clamping device 30 has a fluid pressure cylinder 35 that maintains the mold 21 in a pressed state against the mold 22 held by the opposing wall portion 32 via a movable plate 34, making it possible to fill the cavity 23 with the material for forming the gear 100 at a predetermined pressure.

[0016] The injection device 40 has a hopper 41 that supplies the molding material, a cylinder 42 that fills the mold 20 with the molding material, a screw (not shown) that stirs and discharges the molding material within the cylinder 42, a motor 43 that drives the screw, and a heater (not shown) that melts the molding material within the cylinder 42.

[0017] The hopper 41 supplies, for example, pellet-shaped base resin and reinforcing fibers into the cylinder 42. The base resin pellets and the reinforcing fibers may be separately charged into the hopper 41, or resin pellets containing the reinforcing fibers may be charged. In the cylinder 42, the base resin is melted by the heater, and the resin and reinforcing fibers are stirred by the screw and sent to the tip side of the cylinder 42. At this time, the resin is also melted by shear friction heat caused by the screw. The cylinder 42 has a nozzle at its tip, and can fill the cavity 23 of the mold 20 with stirred molten resin and reinforcing fibers.

[0018] [Placement adjustment mechanism] FIG. 2(A) is an oblique view showing the positional relationship between a gear 100 formed in a cavity 23 of a mold 20 and a placement adjustment mechanism 24 provided in the mold 20, and FIG. 2(B) is an axial cross-sectional view taken along the central axis C of the gear 100 in the cavity 23.

[0019] The arrangement adjustment mechanism 24 is composed of a ring-shaped permanent magnet 241. This permanent magnet 241 is arranged so as to be concentric with the gear 100 in the cavity 23 in the mold 20. In addition, it is assumed that the mold 20 is made of a material that allows the magnetic flux of the permanent magnet 241 to suitably pass through. The inner diameter of the permanent magnet 241 approximately matches the outer diameter of the tooth bottom surface 122 of the gear 100 , and the outer diameter of the permanent magnet 241 approximately matches the outer diameter of the tooth tip surface 123 of the gear 100 . The inner diameter of the permanent magnet 241 may be equal to or larger than the outer diameter of the tooth bottom surface 122 and smaller than the outer diameter of the tooth tip surface 123 , and the outer diameter of the permanent magnet 241 may be larger than the outer diameter of the tooth tip surface 123 .

[0020] Further, the permanent magnet 241 is oriented in a direction along its central axis C (hereinafter referred to as the axial direction) such that the surface facing the gear 100 is the N pole and the opposite surface is the S pole. Note that the orientation of the N pole and S pole may be reversed. With the above arrangement, the magnetic field lines representing the magnetic field generated by the permanent magnet 241 pass through the tooth tip 120 of the gear 100 in the axial direction with the highest magnetic flux density. A yoke having high magnetic permeability for guiding the magnetic lines of the permanent magnet 241 in an appropriate direction may be provided in addition to the permanent magnet 241 .

[0021] In contrast, the reinforcing fibers contained in the molten resin of the gear 100 are made of or contain a ferromagnetic material. Therefore, the molten resin containing the reinforcing fibers is attracted to the magnetic field during the process of filling the cavity 23. This allows the reinforcing fibers to be distributed more in the tooth tip portion 120 of the gear 100 than in the tooth base portion 110.

[0022] 3, the permanent magnets 241 may be disposed on both sides of the cavity 23 in the axial direction. In this case, it is preferable that the polarity of each permanent magnet 241 is aligned in the same direction. This allows the magnetic field lines formed by the permanent magnets 241 on both sides to pass through the tooth tip 120 of the gear 100 in the axial direction with a higher magnetic flux density, so that the reinforcing fibers can be more effectively collected at the tooth tip 120 of the gear 100.

[0023] As shown in FIG. 4, the position adjustment mechanism 24 may have an electromagnet 241A made of a coil instead of the permanent magnet 241, and an electric current supply unit (not shown) that supplies electric current to the electromagnet 241A. The electromagnet 241A may be provided on either one or both sides of the cavity 23 in the axial direction. Electromagnet 241A is ring-shaped and concentric with gear 100 formed in cavity 23, and the inner diameter of electromagnet 241A is approximately the same as the outer diameter of tooth tip surface 123 of gear 100, but may be set to be slightly larger than this. In the case of ring-shaped electromagnet 241A, magnetic field lines pass through the inner diameter side and the outer diameter side, so it is preferable that the outer diameter of electromagnet 241A is larger than that of permanent magnet 241. In addition, when the electromagnet 241A is used, the strength of the magnetic field can be adjusted by adjusting the value of the current applied to the electromagnet 241A by the current-carrying unit. This makes it possible to adjust the ratio of the reinforcing fiber content in the tooth base 110 and the tooth tip 120.

[0024] The reinforcing fibers contained in the molten resin of the gear 100 may be made of or contain a hard magnetic material, so that a magnetized state having polarity in the direction along the fibers can be maintained. In that case, the reinforcing fibers in the cavity 23 can be aligned along the magnetic field lines formed by the permanent magnet 241 or the electromagnet 241A. In the case of the arrangement of the permanent magnets 241 or the electromagnets 241A shown in Figs. 2 to 4 described above, the reinforcing fibers in the gear 100 can be aligned in the axial direction.

[0025] Furthermore, when the reinforcing fibers are to have a magnetic polarity, the magnet 241 or the electromagnet 241A may be arranged so that the magnetic field lines are oriented in the radial direction of the gear 100 formed in the cavity 23. In this case, for example, radially magnetized ring-shaped permanent magnets may be disposed on the radially outer and inner sides of gear 100 formed in cavity 23. Alternatively, electromagnets each having a plurality of coils centered in the radial direction arranged along a circumference concentric with gear 100 may be disposed on the radially outer and inner sides of gear 100.

[0026] [Gear manufacturing using gear manufacturing equipment] The operation of manufacturing gear 100 by gear manufacturing apparatus 1 configured as above will now be described. First, the die 21 of the metal mold 20 is attached to the movable plate 34, and the die 22 is attached to the opposing wall portion 32. Then, in the mold clamping device 30, the fluid pressure cylinder 35 is driven to move the movable plate 34 toward the opposing wall portion 32, and the die 21 is pressed against the die 22. As a result, the cavity 23 between the die 21 and the die 22 is sealed from the outside.

[0027] Meanwhile, pellets of base resin and reinforcing fibers, which are the molding materials for gear 100, are placed in a hopper 41 of injection unit 40. The molding material for gear 100 is then supplied from hopper 41 into cylinder 42, where it is heated by a heater and stirred by a screw. The pellets become molten resin, and are sent by the screw with the reinforcing fibers included therein, to the tip side of cylinder 42, where they fill cavity 23 of mold 20.

[0028] In the mold 20, the permanent magnet 241 of the positioning adjustment mechanism 24 is positioned so that the magnetic field lines pass through the tooth tip portion 120 of the gear 100 in the cavity 23, so that the magnetic reinforcing fibers move to gather at the tooth tip portion 120. Then, after the cooling time for gear 100 has elapsed, mold 21 is separated from mold 22 by mold clamping device 30, and gear 100 is removed from cavity 23, completing the manufacturing process. This produces a gear 100 in which the reinforcing fibers are concentrated more in the tooth tip 120 than in the tooth base 110. Furthermore, in the case where the reinforcing fibers have magnetic polarity, a gear 100 is manufactured in which the fiber direction is uniformly aligned parallel to the magnetic lines of force.

[0029] [Technical effect of embodiment 1] As described above, the gear manufacturing apparatus 1 adjusts the arrangement of the reinforcing fibers by generating a magnetic field using the arrangement adjustment mechanism 24 for the molten resin containing magnetic (ferromagnetic or including ferromagnetic) reinforcing fibers in the mold 20. Therefore, the reinforcing fibers in the molten resin can be guided to a predetermined arrangement within the mold 20, and the gear 100 with the desired reinforced resin arrangement can be properly manufactured.

[0030] In the above-described arrangement adjustment mechanism 24, the permanent magnet 241 is arranged so that the magnetic field lines pass through the gear 100 in a direction along the central axis C of the gear 100, but the present invention is not limited to this. For example, a ring-shaped permanent magnet may be disposed on the radially outer side of the gear 100 to induce more reinforcing fibers on the tooth tip 120 side. Alternatively, ring-shaped permanent magnets may be arranged on the radially outer and inner sides of the gear 100, so that magnetic field lines pass through the gear 100 in a direction along the radial direction of the gear 100. This makes it possible to align the fiber direction of the reinforcing fibers along the radial direction of the gear 100 when the reinforcing fibers have polarity.

[0031] [Embodiment 2] A second embodiment of the present invention will be described with reference to Fig. 5. In the first embodiment, the arrangement adjustment mechanism 24 that forms a magnetic field with magnetic field lines facing a fixed direction (axial direction) for the gear 100 in the cavity 23 is exemplified, but the present invention is not limited to this. In the second embodiment, a gear manufacturing apparatus capable of randomizing the fiber direction of reinforcing fibers of a gear 100 by using a placement adjustment mechanism 24B that generates a rotating magnetic field in which the direction and position of magnetic field lines vary is exemplified. Regarding the gear manufacturing apparatus of the second embodiment, only the differences from the gear manufacturing apparatus 1 will be described, and the same components will be given the same reference numerals and redundant description will be omitted.

[0032] FIG. 5 is a partial side view of the arrangement adjustment mechanism 24B according to the second embodiment as viewed from the axial direction. The arrangement adjustment mechanism 24B has a plurality of permanent magnets 241B arranged closely facing one axial side of each tooth tip portion 120 of the gear 100 in the cavity 23, and a rotation drive unit (not shown) that rotates each permanent magnet 241B.

[0033] Each permanent magnet 241B is magnetized so that a circular surface facing the axial end face of the tooth tip portion 120 is divided into an S pole and an N pole in the diametrical direction. The rotary drive unit rotates the permanent magnet 241B around an axis that is parallel to the central axis C and passes through the center of the circle.

[0034] The permanent magnet 241B is not limited to being circular, and may have a structure in which the S pole and the N pole can alternately face a certain point on the axial end face of the tooth tip portion 120. For example, the shape of the facing surface of the permanent magnet 241B may be different, or one end and the other end of a rod-shaped permanent magnet may be capable of facing the gear 100 alternately. Furthermore, a rotation drive unit may be provided for each permanent magnet 241B. In this case, the rotation speed of each permanent magnet 241B may be uniform or non-uniform. Furthermore, the rotation drive unit may rotate all of the permanent magnets 241B simultaneously using rollers that simultaneously circumscribe the outer periphery of all of the permanent magnets 241B, or may utilize a gear transmission mechanism.

[0035] In a gear manufacturing apparatus equipped with the above-mentioned arrangement adjustment mechanism 24B, each permanent magnet 241B is rotated relative to the molten resin containing reinforcing fibers filled in the cavity 23 of the mold 20. As a result, the reinforcing fibers in each tooth tip 120 of the gear 100 closely facing each permanent magnet 241B are randomly mixed in the rotating magnetic field where the direction and position of the magnetic field fluctuate drastically. This makes it possible to manufacture a gear 100 having a tooth tip 120 in which the orientation of the reinforcing fibers is random. In the arrangement adjustment mechanism 24B, the permanent magnet 241B and the rotation drive unit are provided only on one axial side of the tooth tip portion 120 of the gear 100, but the permanent magnet 241B and the rotation drive unit may be provided on both axial sides.

[0036] The arrangement adjustment mechanism 24B may be used in combination with another arrangement adjustment mechanism. For example, by providing an arrangement adjustment mechanism that forms a magnetic field that attracts reinforcing fibers to the tooth tip portion 120 or a part thereof (for example, the meshing surface 121) and an arrangement adjustment mechanism 24B that forms a rotating magnetic field on the tooth base portion 110 side, the gear 100 may be manufactured in such a manner that, for example, the reinforcing fibers are concentrated on the tooth tip portion 120 side or aligned along the meshing surface 121, while on the tooth base portion 110 side, the individual reinforcing fibers are oriented in random directions.

[0037] [Embodiment 3] A third embodiment of the present invention will be described with reference to Fig. 6. In the third embodiment, a gear manufacturing apparatus is illustrated in which the fiber direction of reinforcing fibers in gear 100 is randomized by means of arrangement adjustment mechanism 24C that generates a rotating magnetic field similar to arrangement adjustment mechanism 24B described above. Regarding the gear manufacturing apparatus of the third embodiment, only the differences from the gear manufacturing apparatus 1 will be described, and the same components will be given the same reference numerals and redundant description will be omitted.

[0038] FIG. 6A is a partial side view of a position adjustment mechanism 24C according to the third embodiment as viewed from the axial direction. The placement adjustment mechanism 24C has multiple sets of electromagnets 241C arranged individually in close proximity to one axial side of each tooth tip portion 120 of the gear 100 in the cavity 23, and an electrical current supply unit (not shown) that supplies AC current to each electromagnet 241C.

[0039] Four electromagnets 241C are arranged close to one axial end face of one tooth tip 120 of the gear 100 in the cavity 23. The coil central axes of the four electromagnets 241C are oriented parallel to the central axis C of the gear 100, and the four electromagnets 241C are arranged at the vertices of a square when viewed from the axial direction of the gear 100. The winding direction of each coil is the same.

[0040] Fig. 6(B) is a diagram showing the waveform of the AC current that the current-carrying unit applies to the four electromagnets 241C. In Fig. 6(B), the horizontal axis is time and the vertical axis is current value. In Fig. 6(A), the four electromagnets 241C are numbered "1", "2", "3", and "4" in counterclockwise order, and these correspond to the numbers given to the four waveforms in Fig. 6(B).

[0041] As shown in the figure, the current supply unit supplies AC current to the four electromagnets 241C with a quarter-cycle delay in accordance with the above-mentioned order of "1," "2," "3," and "4." This creates a rotating magnetic field in which the position of the strong magnetic field lines rotates. The timing pattern of the alternating current applied to the four electromagnets 241C may be changed so that the four electromagnets 241C are not the same. For example, the phase may be shifted regardless of the arrangement order, or two of the electromagnets may have different phases. In that case, it is not a rotating magnetic field, but it is possible to stir the reinforcing fibers and randomize them.

[0042] In a gear manufacturing apparatus equipped with the above-mentioned position adjustment mechanism 24C, the molten resin filled in the cavity 23 of the mold 20 has reinforcing fibers stirred by a rotating magnetic field formed by four electromagnets 241C that are energized at different phases for each tooth tip portion 120. This makes it possible to manufacture a gear 100 having tooth tips 120 in which the reinforcing fibers are randomly arranged within each tooth tip 120 of the gear 100.

[0043] In the arrangement adjustment mechanism 24C, four electromagnets 241C are provided only on one axial side of the tooth tip 120 of the gear 100, but four electromagnets 241C may be provided on both axial sides. Also, the number of electromagnets 241C may be more than one and can be increased or decreased. Moreover, like the placement adjustment mechanism 24B, the placement adjustment mechanism 24C may be used in combination with another placement adjustment mechanism.

[0044] [Embodiment 4] A fourth embodiment of the present invention will be described with reference to Fig. 7. In the fourth embodiment, a gear manufacturing apparatus having an arrangement adjustment mechanism 24D that inputs a stronger magnetic field to an area where reinforcing fibers are arranged at a higher density than to an area where reinforcing fibers are arranged at a lower density is illustrated. In this arrangement adjustment mechanism 24D, a case is illustrated in which the tooth tip 120 of a gear 100 is set as the area where reinforcing fibers are arranged at a higher density, and the tooth base 110 is set as the area where reinforcing fibers are arranged at a lower density. For the gear manufacturing apparatus of the fourth embodiment, only the differences from the gear manufacturing apparatus 1 will be described, and the same components will be given the same reference numerals and repeated description will be omitted.

[0045] FIG. 7A is a perspective view of a position adjustment mechanism 24D according to the fourth embodiment, and FIG. 7B is an axial cross-sectional view thereof. As shown in the figure, the placement adjustment mechanism 24D has the aforementioned permanent magnet 241 that axially faces the tooth tip portion 120 of the gear 100 in the cavity 23, and a permanent magnet 242D that axially faces the tooth base portion 110 of the gear 100 inside the permanent magnet 241.

[0046] For the permanent magnet 242D, a magnet having a magnetic field with a smaller magnetic flux density (smaller magnetic force) than that of the permanent magnet 241 is selected. Like the permanent magnet 241, the permanent magnet 242D is oriented in the direction of the central axis C (hereinafter referred to as the axial direction) such that the surface facing the gear 100 is the N pole and the opposite surface is the S pole. Note that it is preferable to align the N and S poles with the permanent magnet 241, but the orientations of both the permanent magnets 241 and 242D may be aligned in opposite directions. With this arrangement, the magnetic field lines indicating the magnetic field formed by the permanent magnet 242D pass through the tooth base 110 of the gear 100 in the axial direction.

[0047] By the arrangement adjustment mechanism 24D configured as above, reinforcing fibers can be arranged at a high density in the tooth tip portion 120 within the mold 20, and at a low density in the tooth base portion 110 compared to the tooth tip portion 120. This allows the gear manufacturing apparatus to distribute reinforcing fibers to each part of gear 100 with the required strength, making it possible to manufacture gears appropriate for their intended use.

[0048] In the case of the above-mentioned arrangement adjustment mechanism 24D, the permanent magnets 241 and 242D may also be provided on both sides of the gear 100 in the axial direction. Also, in the case of the position adjustment mechanism 24D, the two permanent magnets 241, 242D may be replaced with electromagnets. In this case, it is preferable to adjust the magnetic flux density of the electromagnet replacing the permanent magnet 242D by the number of turns of the coil or the magnitude of the current flowing therethrough.

[0049] [Embodiment 5] A fifth embodiment of the present invention will be described with reference to Fig. 8. In the fifth embodiment, a gear manufacturing apparatus having an arrangement adjustment mechanism 24E for arranging reinforcing fibers more locally so that the fiber direction is along a predetermined surface of the gear 100 is illustrated. The arrangement adjustment mechanism 24E arranges reinforcing fibers on or near the meshing surface 121, the root surface 122, and the tip surface 123 of the tooth tip portion 120 of the gear 100 in a state along each of the surfaces 121-123. For the gear manufacturing apparatus of the fifth embodiment, only the differences from the gear manufacturing apparatus 1 will be described, and the same components will be given the same reference numerals and redundant description will be omitted.

[0050] FIG. 8 is a cross-sectional view perpendicular to the axis of a mold 20 provided with a position adjustment mechanism 24E according to the fifth embodiment. As shown in the figure, the arrangement adjustment mechanism 24E has a permanent magnet 241E that faces each of the meshing surface 121, the bottom surface 122 and the tip surface 123 of the tooth tip portion 120 over the entire circumferential direction of the radially outer side of the gear 100 in the cavity 23. Although the surface of the permanent magnet 241E constitutes the inner surface of the cavity 23 and comes into direct contact with the molding material of the gear 100, the present invention is not limited to this. The permanent magnet 241 may be embedded shallowly in the mold 20 so as not to come into contact with the molding material of the gear 100 .

[0051] The permanent magnet 241E of the arrangement adjustment mechanism 24E attracts the reinforcing fibers to or near the meshing surface 121, the bottom surface 122, and the tip surface 123 within the cavity 23, so that the fiber direction is aligned with each surface. In this way, by using the gear manufacturing apparatus having the arrangement adjustment mechanism 24E, it is possible to gather the reinforcing fibers in the tooth tip portion 120 of the gear 100 and arrange the fiber direction of each reinforcing fiber in accordance with the meshing surface 121, the bottom surface 122 and the tip surface 123.

[0052] In addition, when the fiber direction of each reinforcing fiber is arranged so that it runs along only some of the surfaces, rather than all of the meshing surface 121, the bottom surface 122, and the tip surface 123, it is preferable to provide multiple permanent magnets in the mold 20 that face only those some of the surfaces.

[0053] [Embodiment 6] A sixth embodiment of the present invention will be described with reference to Fig. 9. In each of the first to fifth embodiments described above, the arrangement adjustment mechanisms 24 to 24E each form a magnetic field to control the reinforcing fibers, but in the sixth embodiment, a gear manufacturing apparatus is illustrated that includes an arrangement adjustment mechanism 24F that forms an electric field to control the reinforcing fibers.

[0054] FIG. 9 is a cross-sectional view perpendicular to the axis of a mold 20 provided with a position adjustment mechanism 24F according to the sixth embodiment. As shown in the figure, the positioning adjustment mechanism 24F includes a first electrode 241F that faces the meshing surface 121, bottom surface 122 and tip surface 123 of the tooth tip portion 120 over the entire circumferential direction of the radially outer side of the gear 100 in the cavity 23, a second electrode 242F that faces the inner circumferential surface of the gear 100 over the entire circumferential direction of the radially outer side of the gear 100, and a voltage application device 243F that applies a voltage between the first electrode 241F and the second electrode 242F to generate a potential difference.

[0055] The first electrode 241F and the second electrode 242F of the position adjustment mechanism 24F are provided with an insulating structure with respect to the surroundings. The first electrode 241F and the second electrode 242F may be embedded shallowly in the mold 20 so as not to come into contact with the molding material of the gear 100.

[0056] In the sixth embodiment, the reinforcing fibers contained in the molten resin of the gear 100 are made of an easily charged material (e.g., carbon fiber) or contain an electrostatically charged material. Such an electrostatically charged material has either positive or negative charge polarity, but has a polarity opposite to that of the first electrode 241F arranged in the direction in which the reinforcing fibers are to be attracted. For example, when a positive voltage is applied to the first electrode 241F, the reinforcing fibers are made of or contain an electrostatically charged material that has a negative charge polarity.

[0057] The reinforcing fibers may be prepared in advance in an electrically charged state and then fed into the hopper 41 of the injection device 40, or the injection device 40 may be provided with a charging mechanism for charging the reinforcing fibers. For example, the charging mechanism may be configured to charge the reinforcing fibers by corona discharge when the fibers are fed into the hopper 41, or may be configured to charge the reinforcing fibers by frictional charging. Furthermore, when the reinforcing fibers are made of an electrostatically charged material that easily becomes charged by friction or contain the same electrostatically charged material, the fibers may be configured to be charged by friction during stirring by the screw inside the cylinder 42. In this case, the screw functions as the charging mechanism.

[0058] In the case of a gear manufacturing apparatus equipped with the above-mentioned arrangement adjustment mechanism 24F, when a voltage is applied to each of the electrodes 241F, 242F so that the first electrode 241F has positive polarity, an electric field is formed consisting of electric field lines extending from the first electrode 241F to the second electrode 242F. Then, when the molten resin containing the charged reinforcing fibers is filled into the cavity 23, the negatively charged reinforcing fibers are attracted to or near each of the meshing surface 121, the bottom surface 122, and the tip surface 123, and the fiber direction is aligned with each surface. In this way, by using a gear manufacturing apparatus having the arrangement adjustment mechanism 24F, it is possible to gather the reinforcing fibers in the tooth tip portion 120 of the gear 100 and arrange the fiber direction of each reinforcing fiber in accordance with the meshing surface 121, the bottom surface 122 and the tip surface 123.

[0059] Furthermore, by appropriately adjusting the voltage applied by the voltage application device 243F between the first electrode 241F and the second electrode 242F to be lower, it is also possible to arrange the reinforcing fibers so that they are distributed more in the tooth tip portion 120 than in the tooth base portion 110, rather than along the meshing surface 121, the bottom surface 122, and the tooth tip surface 123.

[0060] Furthermore, if the reinforcing fibers are configured to be charged, for example, so that one side of the fiber direction is positive and the other side is negative, it is also possible to control the fiber direction of the reinforcing fibers to be aligned along the electric field lines of the electric field.

[0061] In addition, when the fiber direction of each reinforcing fiber is arranged so that it runs along only some of the surfaces, rather than all of the meshing surface 121, the bottom surface 122, and the tip surface 123, it is preferable to provide multiple first electrodes 241F on the mold 20 that face only those some of the surfaces.

[0062] [others] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments. For example, in each of the first to sixth embodiments, the gear manufacturing apparatus has been described as manufacturing an external gear as gear 100, but this is not limited to external gears, and it is also possible to manufacture internal gears and various other gears. In addition, the details shown in the above embodiment can be modified as appropriate without departing from the spirit of the invention. [Explanation of symbols]

[0063] 1 Gear manufacturing equipment 11 Bed 20 Mold 21,22 type 23 Cavity 24~24F placement adjustment mechanism 30 Mold clamping device 31, 32 Opposing wall 33 Tie bar 34 Movable plate 35 Fluid pressure cylinder 40 Injection device 41 Hopper 42 cylinders 43 Motor 100 Gears 110 Tooth root 120 Tooth tip 121 Engagement surface 122 Bottom surface 123 Tooth tip 241,241B,242D,241E Permanent magnet 241A,241C Electromagnet 241F 1st electrode 242F 2nd electrode 243F Voltage application device C center axis

Claims

1. A gear manufacturing apparatus for manufacturing gears using a resin containing electrostatically or magnetically reinforcing fibers, A mold into which the molten resin containing the reinforcing fibers is filled; A placement adjustment mechanism that generates an electric field or a magnetic field and adjusts the placement of reinforcing fibers in the molten resin in the mold; Equipped with The arrangement adjustment mechanism is a gear manufacturing device that arranges the reinforcing fibers so that they are more distributed at the tooth tip portion than at the tooth base portion.

2. The position adjustment mechanism generates an electric field for the reinforcing fibers that are filled in the mold and charged.

2. A gear manufacturing apparatus according to claim 1.

3. Has a charging mechanism that charges the reinforcing fibers 3. A gear manufacturing apparatus according to claim 1 or 2.

4. The arrangement adjustment mechanism generates a magnetic field for the reinforcing fibers that are filled in the mold and have magnetism.

2. A gear manufacturing apparatus according to claim 1.

5. A gear manufacturing apparatus for manufacturing gears using a resin containing electrostatically or magnetically reinforcing fibers, A mold into which the molten resin containing the reinforcing fibers is filled; A placement adjustment mechanism that generates an electric field or a magnetic field and adjusts the placement of reinforcing fibers in the molten resin in the mold; Equipped with The arrangement adjustment mechanism generates a magnetic field to the reinforcing fibers filled in the mold and having magnetism, The arrangement adjustment mechanism is a gear manufacturing device that generates a rotating magnetic field.

6. The arrangement adjustment mechanism generates the rotating magnetic field when the fiber direction is random.

6. A gear manufacturing apparatus according to claim 5.

7. The position adjustment mechanism is capable of adjusting the strength of an electric field or a magnetic field.

2. A gear manufacturing apparatus according to claim 1.

8. A gear manufacturing apparatus for manufacturing gears using a resin containing electrostatically or magnetically reinforcing fibers, A mold into which the molten resin containing the reinforcing fibers is filled; A placement adjustment mechanism that generates an electric field or a magnetic field and adjusts the placement of reinforcing fibers in the molten resin in the mold; Equipped with A gear manufacturing apparatus wherein the arrangement adjustment mechanism inputs a stronger electric field or magnetic field to an area where the reinforcing fibers are arranged at a higher density than to an area where the reinforcing fibers are arranged at a lower density.

9. The arrangement adjustment mechanism applies a higher electric field or a higher magnetic field to the tooth tip portion of the gear than to the tooth base portion.

9. A gear manufacturing apparatus according to claim 8.

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