JP2001062936A - Manufacture of gear made of resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure the connecting strength of a tooth constituting body and a metallic bush by employing an annular reinforcing substrate consisting of a continuous woven cloth or non-woven cloth as the tooth constituting body and employing the gear made of resin, in which the tooth constituting body and the metallic bush are connected directly. SOLUTION: A pair of annular reinforcing substrates 12 are arranged in a condition that both of them pinch a rotation preventing member 4 from both sides of the direction of thickness of a metallic bush 3. Tooth constituting body, made of the molded form of an annular reinforcing substrate 12 under this condition, is integrated with the metallic bush 3 to form the gear. A recessed part 14 is arranged on both upper and lower surfaces in the pressurizing direction of a molding mold 13 at a position opposed to a rotation preventing member 4 while the recessed part 14 is opposed also to the upper and lower surfaces of the metallic bush 3 to deform a part of the annular reinforcing substrate 12 by the clamping pressure of the mold and fill the recessed part 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a resin gear, in which a molded article of a resin-impregnated reinforcing base material is used as a tooth component, and a metal bush is insert-molded at the center of the tooth component. In particular, the present invention relates to a method for manufacturing a resin gear in which a tooth component is formed by impregnating a resin into a ring-shaped reinforcing base made of a continuous woven or nonwoven fabric.

[0002]

2. Description of the Related Art The above-mentioned resin gear typically has a structure as shown in FIG. A continuous sheet-like woven fabric is impregnated with a thermosetting resin, and is wound into a rod shape from an end edge. Also, a woven cloth impregnated with a thermosetting resin (0.7 to 2 cm)
Corner 2) and the web 2 located inside the tooth structure 1
And The ring-shaped reinforcing base material and the strips of the woven fabric filled therein are integrated by heat and pressure molding using a metal bush 3 disposed at the center as an insert, and after forming, the teeth are formed into a tooth structure 1 by cutting. Cut. Tooth structure 1
As a continuous sheet-like woven fabric, cotton fabric or aramide fiber woven fabric is used. This is impregnated with a thermosetting resin such as a phenol resin. Further, as the small piece constituting the web 2, a cotton cloth or a glass woven cloth impregnated with a thermosetting resin is cut into 0.7 to 2 cm square.

[0003] On the peripheral surface of the metal bush 3, a detent member 4 protruding in the radial direction is arranged. Since the material forming the web 2 is an independent strip, the strip flows during molding and is sufficiently filled around the detent member 4. Thus, the web 2 and the metal bush 3 are firmly connected.

[0004]

When the diameter of the gear is sufficiently large, the tooth portion and the metal bush are connected by the web as described above, and the material constituting the web is connected to the metal bush by a sufficient strength. Can be selected.
However, as the diameter of the gears decreases, there is no room for placing the web, and the tooth structure and the metal bush must be directly connected. However, since the ring-shaped reinforcing base material of the tooth component body is made of a continuous woven fabric for the purpose of ensuring the strength of the teeth, the flow during molding is small. Since it is not expected that the ring-shaped reinforcing base material is sufficiently filled around the detent member, it is difficult to secure the bonding strength between the tooth component formed with the ring-shaped reinforcing base material and the metal bush.

[0005] In the production method according to the present invention, a ring-shaped reinforcing base made of a continuous woven or non-woven fabric is used for a tooth structure,
It is intended for a resin gear in which a tooth component and a metal bush are directly coupled. The problem to be solved by the present invention is to produce a resin gear in which the reinforcing base material has little disturbance and the coupling strength between the tooth component and the metal bush is sufficiently ensured.

[0006]

In order to solve the above-mentioned problems, a method of manufacturing a resin gear according to the present invention comprises a metal bush having a radially projecting detent member disposed on a peripheral surface thereof. A ring-shaped reinforcing substrate made of a woven or non-woven fabric is put into a molding die, and the ring-shaped reinforcing substrate is placed around a metal bush and pressed in the thickness direction of the metal bush. Then, the ring-shaped reinforcing base material is impregnated with the liquid resin injected into the molding die, and is heated and molded to manufacture a resin gear having a molded product of the resin-impregnated ring-shaped reinforcing base material as a tooth structure. At this time, the ring-shaped reinforcing base is arranged such that a pair of the ring-shaped reinforcing bases constitutes a pair and sandwiches the rotation preventing member from both sides in the thickness direction of the metal bush. Then, a concave portion is arranged at a position corresponding to the detent member on the upper and lower surfaces in the pressing direction of the molding die, and a part of the ring-shaped reinforcing base material is filled in the concave portion by pressing. Things.
In another manufacturing method, a metal bush in which a detent member that protrudes in the radial direction is arranged on the peripheral surface, and a resin-impregnated ring-shaped reinforcing base made of a continuous woven or nonwoven fabric are put into a molding die, and a ring is formed. The metal-made bushing is placed around the metal bush, pressure is applied in the thickness direction of the metal bush, and the product is molded under heat and pressure to manufacture a resin gear with the resin-impregnated ring-shaped reinforcing base as a tooth structure. I do. At this time, the ring-shaped reinforcing base is arranged such that a pair of the ring-shaped reinforcing bases constitutes one set and sandwiches the detent member from both sides in the thickness direction of the metal bush. Then, a concave portion is arranged at a position corresponding to the detent member on the upper and lower surfaces in the pressing direction of the molding die, and a part of the ring-shaped reinforcing base material is filled in the concave portion by pressing. Things.

As described above, in the method of manufacturing a resin gear according to the present invention, the tooth structure and the metal bush are formed in such a manner that the ring-shaped reinforcing base is formed with the detent member sandwiched therebetween from above and below. Therefore, the coupling strength between the tooth component body and the metal bush can be made sufficient. Due to the molding pressure applied in the thickness direction of the metal bush, the ring-shaped reinforcing base material sandwiching the detent member from above and below bites into the detent member, and sufficient bonding strength can be secured. Further, in the method according to the present invention, a part of the ring-shaped reinforcing base material is deformed by the pressure and is filled in the concave portion. In a mode in which the concave portion is not provided, the density of the ring-shaped reinforcing base material around the base member is increased due to the presence of the detent member, and the orientation of the base material is disturbed. However, if the concave portion is arranged, the ring-shaped reinforcing base material excluded due to the presence of the detent member is filled in the concave portion, so that the orientation disorder of the base material is reduced,
It is possible to further increase the bonding strength between the tooth part structure and the metal bush.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In practicing the present invention, a ring-shaped reinforcing substrate is manufactured as follows. As shown in FIG. 2, a tubular woven fabric 11 is rolled up in an axial direction from an end portion to form a ring-shaped reinforcing base material 12. Although a straight tube is shown in the figure, a bellows tube may be used. If the tubular woven fabric 11 is made by knitting and has elasticity, the winding work can be easily performed, which is convenient. Also,
The ring-shaped reinforcing substrate having elasticity as described above is also preferable in terms of mechanical properties of the gear. Details will be described later. In another means, as shown in FIG. 3, a sheet-shaped woven fabric 11 is wound around an edge to form a rod-shaped body, and the rod-shaped body is formed into a ring to form a ring-shaped reinforcing base material 12. In the embodiment shown in FIG. 2, it is difficult to use a nonwoven fabric instead of the woven fabric 11, but FIG.
In the embodiment shown in (1), there is no difficulty in using a nonwoven fabric instead of the woven fabric 11. Further, as another means, the production of the ring-shaped reinforcing substrate can be performed as follows. One is a means for winding a sheet-like woven or non-woven fabric into a tubular shape, and further compressing the tubular body in the axial direction to form a ring. The number of times of winding in a cylindrical shape may be one, or may be more than one, and may be lap winding. The other is a means for compressing a nonwoven fabric formed in a ring shape or a cylindrical shape from the beginning in the axial direction into a ring.

Using the above-described ring-shaped reinforcing base material, a pair of the ring-shaped reinforcing base materials constitute one set, and
Are sandwiched from both sides in the thickness direction of the metal bush 3 to form a resin gear in which the tooth structure 1 formed with the ring-shaped reinforcing base material and the metal bush 3 formed by insert molding are integrated. As shown in FIG. 1, the ring-shaped reinforcing base material is deformed at a position corresponding to the position of the rotation preventing member 4, and accordingly, the tooth structure 1 is formed so as to protrude around the metal bush 3. I do.

The molding is performed as follows. As shown in FIG. 4, a metal bush 3 in which a rotation preventing member 4 protruding in the radial direction is arranged on a peripheral surface and a ring-shaped reinforcing base 12 are formed into a molding die 1.
Put in 3. The ring-shaped reinforcing base material 12 is arranged around the metal bush 3 arranged at the center, and the pair of ring-shaped reinforcing base materials 12 sandwich the detent member 4 from above and below. That is, the inner diameter of the ring-shaped reinforcing base 12 is set smaller than the outer diameter of the metal bush 3 including the rotation preventing member 4. The mold is clamped in this state, and the pressure is used to deform the ring-shaped reinforcing base material 12 so that the ring-shaped reinforcing base material 12 bites into the detent member 4. Alternatively, the ring-shaped reinforcing substrate 1
2 is wrapped around the detent member 4. Mold 1
Since the concave portions 14 are arranged at positions corresponding to the rotation preventing members 4 on the upper and lower surfaces in the pressing direction 3, a part of the ring-shaped reinforcing base material 12 is deformed by the pressure of the mold clamping to form the concave portions 14. Will be filled. If the ring-shaped reinforcing base 12 is made to have elasticity, the ring-shaped reinforcing base 12 is easily deformed, so that the rotation preventing member 4 can bite or the ring-shaped reinforcing base 12 can be satisfactorily wrapped. In addition, the recess 14 can be favorably filled. Then, a liquid resin (CP resin: crosslinked polyesteramide, crosslinked polyaminoamide, epoxy resin or polyimide) is injected into the mold in a reduced pressure state, impregnated into a ring-shaped reinforcing base material, and heat molded. FIG.
FIG. 4 is a cross-sectional view showing a result of molding. The ring-shaped reinforcing substrate has a concave portion 14 corresponding to the position of the rotation preventing member 4.
, So that the tooth part structure 1 has a shape protruding around the metal bush 3. It is advantageous to form the anti-rotation member 4 into an undercut shape having a large tip and a small base so that the coupling strength between the tooth component body and the metal bush can be further increased. In the above example, two ring-shaped reinforcing bases 12 are overlapped, and the detent member 4 is sandwiched from above and below. When three ring-shaped reinforcing bases 12 are stacked for the sake of increasing the thickness of the gears, the detent members 4 are arranged in two rows on the peripheral surface of the metal bush 3. Then, one of the detent members is sandwiched between the ring-shaped reinforcing base material having a pair of the upper and the center, and the other detent member is sandwiched by the ring-shaped reinforcing substrate having the pair of the center and the lower portion.

In the embodiment of the present invention, the ring-shaped reinforcing substrate is placed in a molding die, and a liquid resin is injected into the molding die to impregnate the ring-shaped reinforcing substrate. In another embodiment, a ring-shaped reinforcing base material previously impregnated with a thermosetting resin is placed in a molding die, and molded in the same manner as described above without injecting a liquid resin. The ring-shaped reinforcing substrate pre-impregnated with thermosetting resin is
It can be manufactured as follows. In the means described with reference to FIG. 3, first, the sheet-like woven fabric 11 (or sheet-like nonwoven fabric) is impregnated with a thermosetting resin and dried to form a prepreg. In this method, the prepreg is wound around the edge while being heated to form a rod-shaped body, and the rod-shaped body is formed into a ring to form the ring-shaped reinforcing base 12. A method in which the prepreg is wound in a tubular shape, and the tubular body is compressed in the axial direction and temporarily formed to form a ring to form the ring-shaped reinforcing base material 12 may be used. Further, in another means, a non-woven fabric formed in a ring shape or a cylindrical shape from the beginning is impregnated with a thermosetting resin and dried to obtain a prepreg. This may be compressed in the axial direction and temporarily formed, and then formed into a ring to form the ring-shaped reinforcing base 12.

[0012]

Example 1 A knitted tubular aramid fiber woven fabric was rolled up from the end in the axial direction to form a ring-shaped reinforcing substrate. Using this ring-shaped reinforcing substrate, molding was performed by the method described with reference to FIG. The impregnation of the resin into the ring-shaped reinforcing base material was performed by injecting a CP resin into a molding die in a reduced pressure state.

Example 2 A molding was performed in the same manner as in Example 1 except that a plain-woven tubular aramid fiber woven fabric was used.

Comparative Example 1 In Example 1, molding was performed in the same manner as in Example 1 except that the concave portion 14 was not arranged in the molding die.

Comparative Example 2 A knitted tubular aramid fiber woven fabric was rolled up from the end in the axial direction to obtain a ring-shaped reinforcing substrate. The inner diameter of the ring-shaped reinforcing base material is set to be approximately the same as the outer diameter of the metal bush including the rotation preventing member, and a molding die without the recessed portion 14 is used. did. In this comparative example, the inner periphery of the ring-shaped reinforcing base material charged into the molding die is located outside the tip of the detent member.

Comparative Example 3 A molding was performed in the same manner as in Comparative Example 2 except that a plain-woven tubular aramid fiber woven fabric was used.

In each of the resin gears of the above-described examples, the teeth were cut by cutting the tooth structure. Further, at the time of cutting, a convex portion formed by filling the concave portion 14 with the ring-shaped reinforcing base material and the resin was removed together. Table 1 shows the results of measuring the breaking strength between the tooth component and the metal bush. The measuring method is a method in which a resin gear is meshed with a fixed steel counterpart gear, and the rotation axis of the resin gear is twisted to measure the breaking strength between the tooth component body and the metal bush. .
The breaking strength was the size at which cracks occurred in the tooth component, and the measured values of two resin gears were shown.

[0018]

[Table 1]

[0019]

As described above, the resin gear according to the present invention has a structure in which the tooth portion structure formed by molding the ring-shaped reinforcing base made of a continuous woven or nonwoven fabric and the metal bush are directly connected. Nevertheless, the bonding strength can be sufficiently ensured. As is clear from the comparison between Example 1 and Comparative Example 1, the method according to the present invention has very good bonding strength because the ring-shaped reinforcing base material has little disturbance. In the case where the ring-shaped reinforcing substrate has elasticity, the rotation-stopping member is more likely to bite into the ring-shaped reinforcing substrate, and a larger bonding strength can be secured (Example 1).

[Brief description of the drawings]

FIG. 1 is a sectional view of a resin gear manufactured by a method according to the present invention.

FIG. 2 is an explanatory view showing a step of preparing a ring-shaped reinforcing base material for a tooth part structure in the production of the resin gear according to the present invention.

FIG. 3 is an explanatory view showing another step of preparing a ring-shaped reinforcing base material for a tooth part structure in the production of the resin gear according to the present invention.

FIG. 4 is an explanatory cross-sectional view showing how a resin gear according to the present invention is molded.

FIG. 5 is an explanatory sectional view showing a conventional resin gear.

[Explanation of symbols]

 1 is a tooth structure 2 is a web 3 is a metal bush 4 is a detent member 11 is a woven fabric 12 is a ring-shaped reinforcing base material 13 is a molding die 14 is a concave portion

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4F213 AA36 AA39 AA41 AD03 AD16 AG28 AH12 WA02 WA53 WA57 WA83 WA87 WA89 WB01 WC01 WK02

Claims (7)

[Claims] 1. A metal-made bush having a detent member protruding in a radial direction disposed on a peripheral surface thereof and a ring-shaped reinforcing base made of a continuous woven or non-woven fabric are put into a molding die, and a ring-shaped reinforcing base is provided. The material is placed around the metal bush, pressurized in the thickness direction of the metal bush, and the liquid resin injected into the molding die is impregnated into the ring-shaped reinforcing base material and heated to form a resin-impregnated ring-shaped reinforcing base material. In manufacturing the resin gear having the molded product of the tooth portion as the tooth component body, the arrangement of the ring-shaped reinforcing base material is such that a pair of the ring-shaped reinforcing base materials constitute a set and the detent member has a metal bush thickness. The concave part is arranged at the position corresponding to the detent member on the upper and lower surfaces in the pressing direction of the molding die, and a part of the ring-shaped reinforcing base material is pressed into the concave part by pressing. A method for producing a resin gear, characterized by filling. 2. A metal bush having a detent member protruding in the radial direction disposed on a peripheral surface thereof, and a resin-impregnated ring-shaped reinforcing base made of a continuous woven or non-woven fabric are put into a molding die, and the ring-shaped base is fed. A resin gear in which a reinforcing base material is arranged around a metal bush, pressure-applied in the thickness direction of the metal bush and subjected to heat and pressure molding, and a molded product of a resin-impregnated ring-shaped reinforcing base material is used as a tooth structure. In manufacturing, the arrangement of the ring-shaped reinforcing base material is performed such that a pair of the ring-shaped reinforcing base materials form a pair and sandwich the detent member from both sides in the thickness direction of the metal bush. A method of manufacturing a resin gear, characterized in that a concave portion is arranged at a position corresponding to a rotation preventing member on upper and lower surfaces in a pressing direction, and a part of a ring-shaped reinforcing base material is filled in the concave portion by pressing. . 3. The ring-shaped reinforcing substrate is formed by winding a tubular woven fabric in an axial direction from an end portion into a ring.
The method for producing a resin gear as described in the above. 4. The resinous material according to claim 1, wherein the ring-shaped reinforcing base material is formed by winding a sheet-like woven or non-woven fabric from an edge to form a rod-shaped body, and further forming the rod-shaped body into a ring. Gear manufacturing method. 5. The ring-shaped reinforcing substrate according to claim 1, wherein the sheet-shaped woven or non-woven fabric is wound into a tubular shape, and the tubular body is further axially compressed into a ring. Manufacturing method for resin gears. 6. The method for manufacturing a resin gear according to claim 1, wherein the ring-shaped reinforcing substrate is formed by compressing a ring-shaped or cylindrical non-woven fabric in an axial direction into a ring. 7. The method for manufacturing a resin gear according to claim 3, wherein the ring-shaped reinforcing base has elasticity.