JP2554984B2 - Internal gear forming method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic transmission for an automobile, etc., which is housed in a container case filled with lubricating oil and is adapted to circulate the oil inside the container case by rotation. The present invention relates to a method for forming an internal gear, which is related to a gear and is lightweight and easily manufactured.

[0002]

2. Description of the Related Art In an automatic transmission (torque converter) of an automobile and other equipment, lubricating oil or hydraulic control oil filled in a casing is agitated by rotation of an internal gear, and an internal gear and an external gear are agitated. Internal gears are used that are freely distributed. It is desirable that the internal gear that acts in this way be made lightweight in order to reduce inertia and further reduce energy loss. For this reason, the steel material cut to the required size is heated to the required temperature, hot or warm forged into a roughly internal gear shape, and then internal teeth are machined on the inner peripheral surface of this material. The finished product is cut by processing. Alternatively, the boss portion and the drum portion are separately manufactured, and then both members are joined by welding to be integrated.

[0003]

Therefore, in the conventional processing method, it is necessary to heat the material to a temperature required for hot or warm forging, and further, forging and mechanical processing are required in the processing step. After machining, a separate heat treatment process is required to increase the strength of the product, resulting in an increase in the number of manufacturing processes and a poor yield of the used steel material. Further, in the method of joining the boss portion and the drum portion, which are individually formed, by welding, distortion occurs due to the heat effect, and it is difficult to maintain the accuracy by spinning forming. Furthermore, there is a limit to weight reduction, and it is not possible to achieve extreme weight reduction.

It is an object of the present invention to mechanically join a boss member of a different type or the same type to a drum member, and to form a desired tooth mold with high precision on the drum portion by spinning and to reduce the weight.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above-mentioned object, and is made from a plate-shaped material by considering a boss member having a required strength and shape and a mass of an internal gear to be formed in the boss member. The obtained disc-shaped drum member is overlaid, and it is rotated at the required number of revolutions and is clamped by a molding die having a tooth mold on the outer peripheral surface and a pressing die, and the center of rotation of this molding die While pressing a plurality of molding rollers concentrically arranged in an annular shape against the boss member and moving the mold roller along the mold to form a tooth mold on the inner peripheral surface of the drum portion by cold plastic pressure, the boss member and the drum The gist is that the member is integrated with the member and the internal stress generated in this molding process is used to increase the strength of the drum portion.

[0006]

The preformed boss portion and the plate-shaped drum portion member are pressed and sandwiched between the molding die and the pressing die, and in this state, a plurality of moldings are performed from the outer peripheral portion while rotating at a predetermined rotational speed. The pressing roller is pressed and moved along the longitudinal direction of the molding die. As a result, the disk-shaped drum member is cold plastically worked. The internal stress generated during this processing increases the strength of the material, and the two members are pressure-bonded to each other to be integrated. Therefore, since there is no welding process, distortion due to the influence of heat does not occur, and high precision manufacturing is possible. It can also be manufactured using a material that cannot be welded.

[0007]

EXAMPLES A method for forming an internal gear of the present invention will be described below with reference to the illustrated examples. In the figure, reference numeral 1 denotes an internal gear molded by the method of the present invention, which is an annular drum portion 2 having a required diameter and thickness and a tooth profile on the inner peripheral surface, and one end side surface of the drum portion. The boss portion 3 has a boss hole having a diameter, and the boss portion and the drum portion of the same kind or different types are integrally manufactured by cold plastic working. The thickness of the plate-shaped boss material W for molding the drum portion 2 of the internal gear 1 is 3 to 15
mm, the outer diameter of the moldable internal gear is 80 to 200 mm, and is appropriately determined within the range, but the plate thickness of the boss material and the gear outer diameter are not necessarily limited to the above range.

Next, a case will be described in which an internal gear having a required outer diameter is formed by cold plastic working using iron as the boss, aluminum as the drum, and a plate-shaped material as the drum. The boss portion 3 is formed by pressing or forging an iron plate into a desired boss portion shape in advance. In this, a short tubular collar 32 is integrally formed on the outer circumference of a flange 31 having the same diameter as the outer diameter of the internal gear to be molded or a diameter slightly smaller than that. Then, the member 2 of the drum portion is overlaid on the flange 31 of the boss portion. At this time, the centers of both members are aligned.

The member of the drum portion is manufactured into a disk shape having a predetermined plate thickness and diameter calculated from the mass of the internal gear to be molded. Of course, the member diameter of the drum portion is larger than the diameter of the boss portion. A plurality of depressions or projections are formed on the boss side, for example, on the outer peripheral surface of the flange of the boss so that the boss and the drum are firmly pressed and fixed only by pressure molding. The shape and the number of the depressions or protrusions are appropriately determined so that the torque can be sufficiently transmitted between both members integrally.

Next, both the boss portion and the drum portion are strongly sandwiched between the molding die 10 for spinning molding and the pressing die 20. The molding die 10 has the diameter and size of an internal gear to be molded, and a required tooth profile H is formed on the outer peripheral surface of the mold. This tooth profile H is an external gear (not shown) that is fitted in and meshes with the internal gear as shown in FIG.
And the number of teeth corresponding to the diameter and the number of teeth of the external gear so that the tooth profile portions mesh with each other and rotate.

The pressing die 20 cooperates with the flat surface portion of the molding die 10 to support the flange portion of the boss portion by sandwiching it, and furthermore, the both dies 10 and 20 are arranged on the same rotary shaft,
It has a smaller diameter than the molding die. And both molds 10, 20
The pressure for sandwiching both the molding boss portion and the drum portion member therebetween is determined so as to be firmly supported even when the pressing die 10 is rotated and the forming material is subjected to cold plastic working by the forming roller. To be

At the outer peripheral position of the molding die 10, two to a plurality of molding rollers 30 are arranged at substantially equal intervals or at arbitrary positions. All the molding rollers 30, 30 ... Have the same shape and the same size or different shapes, and are arranged in the radial direction of the molding die 10 and at an arbitrary interval from the center of rotation of the die 10. It is rotatably supported.

Next, the molding roller 30 is pressed against the outer peripheral surface of the mold 10 with a predetermined pressure, which is perpendicular to the rotation of the mold 10 and which is suitable for the type of the member of the drum part. Pressed with. The molding member sandwiched between the molds 10 and 20 is rotated at a required rotation speed, for example, 50 minutes per minute.
Forming roller 30, while rotating at 0 to 1000 revolutions,
.. are moved along the longitudinal direction of the molding die 10 from the outer peripheral position of the upper end of the molding die 10 at a required feed rate per minute.

As described above, the member of the drum portion is subjected to cold plastic working by the combination of the rotation of the molding member sandwiched between the two dies and the pressing movement of the molding roller to continuously mold it into a cup shape. At this time, according to the shape of the outer peripheral surface of the molding die, the inner teeth are simultaneously formed on the inner peripheral surface of the annular portion at regular intervals, and the depressions or projections formed on the flange of the boss portion are pressed, and the plasticity of the member of the drum portion is pressed. Is integrated by crimping. At this time, the pressing force of the forming roller is kept constant and is controlled by NC control to adjust the outer peripheral shape of the internal gear. Since the forming roller 30 follows the rotation of the material, the outer periphery of the forming roller and the die is The peripheral speeds of the outer peripheral surface of the forming material formed by the surfaces are equal, and the peripheral speed is suitably 300 to 550 m / min.

In this way, the internal gear is formed by cold forging while enhancing the strength by cold plastic working, and the clamping force of the material between the two molds, the rotation speed and the pressing force of the forming roller are used. In addition, the moving pressure and the like are appropriately selected depending on the type of molding material and the size and shape of the molded product. In addition, since the two members of the boss portion and the drum portion are mechanically joined in this way, distortion due to heat does not occur, and it is possible to manufacture with high precision and both members are of the same type or Even different kinds of materials and even materials that cannot be welded can be easily manufactured.

Further, in a forged product in which a cylindrical boss is integrally formed in the center of the boss member, a plate-shaped drum member is formed along the flange side surface protruding from the outer peripheral surface of the cylindrical boss, and similarly formed integrally. You can also do it.

Although the above embodiment has described the molding of the internal gear, the molding according to the present invention can be applied to the internal gear, the pre-process material for the globe molding method, the simple drum molding, etc. by changing the shape of the molding die. Can also be applied.

[0018]

The internal gear forming method of the present invention comprises a boss member having a required strength and shape, and a required disk-shaped drum member obtained from a plate-shaped material from the mass of the internal gear formed on the boss member. Are overlapped with each other, are rotated at a required number of revolutions, and are sandwiched by a molding die having a tooth mold on the outer peripheral surface and a pressing die, and a plurality of annularly arranged concentrically with the center of rotation of the molding die. While pressing the molding roller against the boss member, the mold is moved along the mold to form a tooth mold on the inner peripheral surface of the drum portion by cold plastic pressure, and the boss member and the drum member are integrated, so The accuracy can be easily maintained without being affected by distortion or the like. Further, there is an advantage that it is possible to join materials that cannot be welded to each other regardless of the types of both members.

[Brief description of drawings]

FIG. 1 is a partially cutaway external perspective view of an internal gear of the present invention.

FIG. 2 is an explanatory view showing a manufacturing process of an internal gear of the present invention.

FIG. 3 is an explanatory view showing a molding process of another embodiment.

FIG. 4 is a spinning forming diagram of an internal gear.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Internal gear 2 Drum part 3 Boss part 31 Flange 32 Tsuba 10 Mold for molding 20 Stamping mold 30 Molding roller

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Bibliography West German patent application publication 3931599 (DE, A) Mechanical Engineering Handbook Revised 6th Edition The Japan Society of Mechanical Engineers (Published July 20, 1979) 17th edition 64- Page 66 Illustrated Machine Term Encyclopedia, Industrial Education Study Group, Published by Nikkan Kogyo Shimbun (Published July 30, 1975) Page 355

Claims (1)

(57) [Claims] 1. A boss member having required strength and shape,
A molding die having a required disk-shaped drum member obtained from a plate-shaped material by superposing the mass of the internal gear to be molded on this boss member, rotating the drum member at a required number of revolutions, and having a tooth mold on the outer peripheral surface. And a pressing die, and while pressing a plurality of molding rollers arranged annularly concentrically with the center of rotation of the molding die against the boss member, move along the die and apply cold plastic pressure. A feature is that a tooth mold is molded on the inner peripheral surface of the drum part, the boss member and the drum member are integrated, and the internal stress generated in this molding process is used to increase the strength of the drum part. Internal gear forming method.