JPS6160732B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for forming a reverse slope as a contact surface of mutually engaging dogs in a dog type clutch mechanism in order to prevent dogs from becoming disengaged during power transmission, and a forming device therefor. .

Generally, dog-type clutch mechanisms are widely used in power transmission mechanisms, transmissions, etc. of motorcycles and various mechanical devices. Among these, it is known to provide a reverse slope to the meshing contact surface in order to prevent accidents in which the dog meshing becomes disengaged during power transmission.

In recent years, due to advances in manufacturing technology, it has become possible to manufacture various types of clutch dogs, especially small ones, with sufficient precision for practical use by leaving the meshing surface as a forged skin with zero draft, and this has been done for some time. It is replacing the total machining method.

However, with a reverse slope dog, as the name suggests, the dog part slopes in the opposite direction to the forging draft, so even if forging can be performed, the product cannot be extracted from the mold as it is. Since no suitable method has been found to solve this problem, conventional reverse slope dogs have had no choice but to rely entirely on machining methods. This machining method requires a lot of man-hours because it requires cutting out each of the two to six dogs one by one.
In addition, the cross-sectional dimensions are increased in design because the connection of the metal structure at the dog root, which has an important effect on the dog strength, is removed as shown by the line of the reverse slope dog part 2' in Figure 4a. Special consideration was required.

The purpose of the present invention is to solve these problems, and the purpose of the present invention is to create an intermediate molded product in which the dog part forms a columnar body with no slope and a predetermined dimension by a method such as casting, and then mold this product. The intermediate molded product of the non-gradient columnar body is formed by a press or the like using a molding die with a split assembly structure so that it can withstand pressure at times and the product can be separated after the intermediate molded product has been molded into a reverse slope dog. The present invention provides a method for molding an arbitrary reverse gradient dog by applying pressure, and a molding apparatus for the same. By this method, in place of the conventional machining method, it was possible to efficiently obtain a dog product with a reverse slope of the clutch, which has a high precision, continuous metal structure, and excellent strength.

An embodiment of the molding method of the present invention will be described in detail with reference to the drawings. FIG. 1 is a longitudinal cross-sectional view of a dog-type clutch, and FIG. It is a perspective view of gear 1, and three reverse slopes θ
FIG. 3 is a perspective view of the intermediate molded product 3 in which the dog portion 2 forms a columnar body with no slope before molding. FIG. 4a shows a cross section of a conventional dog portion 2' in which the flow of the metal structure is cut and becomes discontinuous by cutting as described above, and FIG. This shows a cross section of part 2, showing that the flow of the metal structure is continuous. FIG. 5a is a sectional view of the non-gradient dog portion 4 of the columnar intermediate molded product 3, which is set in a reverse gradient dog mold 5 as shown in FIG. 5b, and is indicated by an arrow from above. By pressing P so that it is seated in the same manner as shown in FIG. In this case, among the dimensions of the non-gradient columnar body, the height H is
is a dimension slightly higher than the height H' of the desired reverse slope dog part 2, and the width B of the intermediate molded product of the columnar body is set to the minimum width B' of the required reverse slope dog part dimension. The columnar dog part 4 is inserted into the mold 5, compressed and expanded, deformed and bulged as shown in FIG. This results in a molded dog part.Furthermore, compression processing of the non-gradient columnar body can also be performed by pressing the bottom part 7 of the mold 6 from below in the direction indicated by the arrow as shown in FIG. 6b. Yes, it is possible. Figure 7 shows the non-gradient dog columnar body 8 of the intermediate molded product.
The dimensions are Width B and Height H, and Width B is the dimension that matches the maximum width B'' of the required reverse slope dog part dimensions, and the height H is also calculated from the finished height H', taking into account the surrounding area at the time of finishing. With dimensions slightly lower, this intermediate molded product is set in the reverse slope molding molds 9, 9 as shown in Fig. 7b, and pressures P and P' are applied from the lateral direction by sandwiching the molded product from the sides. In particular, as shown in Figure c, reverse slope forming is performed by squeezing the dog base N.In order to separate the formed reverse slope formed dog part from the movable mold, dog die carving is performed. As shown in FIG. 8b, one of the two opposing slope molding surfaces 10 of the part is formed from the molded state shown in FIGS. 8a and 9a.
Or both 11, 11' as shown in Figure 9b.
are moved away from each other to release the reverse gradient constraint. Therefore, the mold needs to have a split movable structure. The opening of the above-mentioned reverse slope surface is the maximum width of the dog part 2 forming the minimum width B of the reverse slope molding part of the mold.
It must be opened until the distance is greater than or equal to B''.The opening directions are tangential directions C and C' as shown in Figure 10 when looking at the mold in plan, and along the circumference as shown in Figure 11. There are two directions, D and D'.When viewed from the front, both can be said to be the width direction of the reverse slope forming dog.

An example of a molding apparatus for carrying out the molding method of the present invention will be explained in detail with reference to the drawings. FIG. 12 is a plan view of the main parts thereof, FIG. 13 is a perspective view thereof, and FIG. 14 is a press lowering operation. It is a vertical cross-sectional view of the device, and the molding die has a knockout hole 12 in the center.
A fixed mold part 13 in the shape of a disc and a cutout part 14 provided in the fixed mold part 13 according to the required number of dogs (three in the illustrated embodiment) and a movable mold part provided in the cutout part 14. 15, and a punch part 21 having a ring body 20 circumferentially surrounding the movable mold part and holding it in a fixed position, which will be described later, during reverse slope molding, and a punch part 21 having a ring body 20 surrounding the movable mold part and holding it in a fixed position, which will be described later. A die-scaved portion 16 for forming the reverse slope dog portion is recessed, and the die-scaved portion 1
6 is provided with one side 17 of opposing reverse slope molding surfaces, and the other molding surface 18 is located in an opening 19 communicating with the notch 14, and the said molding surface 18 is arranged so that the position that closes the opening 19 is the home position. The movable mold part 15 is rotatably mounted on the cutout part 14 by a support pin 22, and is formed by a surface that closes the opening 19. In this way, the movable mold part 15 complements the mold engraving part 16 by forming one side of the reverse slope molding at the fixed position. As shown in FIG. 12, this movable mold part 15 is always pressed and biased by a spring 23 so as to assume the above-mentioned fixed position. During reverse slope molding, the 15th and 1st
As shown in FIG. 6, it is pressed by the ring body 20 of the punch portion 21 so as not to rotate outward. The face 21' of the central die-cut part of the punch part 21 is shaped to match the shape of the back side of the clutch intermediate molded product 3, that is, the opposite side of the columnar body, and the peripheral edge forms the ring body 20. With each movable mold part 15 being pressed into position by the spring 23 and both molding sides of the molding part 16 closed, the non-gradient dog columnar body 4 of the intermediate molded product 3
is inserted. As shown in FIG. 6a, the length of this columnar body 4 is slightly higher than the height of the die-cut portion 16, and its width is adjusted to the minimum width B'. In this way, the non-gradient columnar body 4 is set in alignment with the die-cutting part 16, and as shown in FIG. 14 and FIGS. 1
5 and presses its rotation. Then, the surface 21' of the die-scaved part in the center of the punch part 21 hits the back side of the intermediate molded product 3, pressurizes the inside of the die-scaved part 16. Then, the head of the columnar body 4 is expanded and molded to form the reverse slope dog part 2. After molding, the punch part 21 separates from the product and rises, and the ring body 2
0 also comes off from the outside of the movable mold part 15, and the movable mold part 15
is also in a state where it can rotate around the pin 22 as shown in FIG. Next, as shown in FIG. 17, the clutch element of the reverse slope dog part 2 formed by the knockout pin 24 is pushed up, and this movement causes the product dog part to slide on the reverse slope molded surface 17 on the fixed mold member side. At the same time, the movable mold part 15, which has been released from the restraints from the outer periphery, is moved upward with a twisting motion, and the movable mold part 1
The reverse slope molding surface 18 of No. 5 moves in the tangential direction and is pushed out a distance equal to or greater than the height H' of the molding dog portion, thereby completing the product's release from the mold.

Further, as shown in FIG. 7a, the width of the non-gradient columnar body 4 of the intermediate molded product 3 is equal to the maximum width B of the required dog part dimension, and from the intermediate molded product 3 whose height is slightly lower, a reverse slope dog is When molding, the structure is basically the same as that shown in Figs.
Using a mold having a structure in which an elastic body 25 such as rubber is provided on the back side of the punch part 21' as shown in FIG.
It is inserted and set into the die-cut portion 16 against the pressure.

When the press is lowered, the punch portion 21' via the elastic body 25 first presses the intermediate molded product 3 with a predetermined pressure as shown in FIG. 19, and then the press lowers as shown in FIG. Due to the movement, the inner tapered surface of the pressing ring body 20 moves into the movable mold part 15.
is pushed inward by the cam action, and the movable mold part 1
5 rotates around the support pin 22, thereby applying pressure from the side to the reverse slope forming side surfaces 17 and 18 facing the columnar part 4 of the intermediate workpiece 3, forming the reverse slope dog portion 2. . The product is removed after molding in the same manner as shown in FIGS. 17 and 18.

By the method of the present invention, the forming of the reverse gradient dog part is carried out in mass production without cutting the flow of the metal structure and therefore without losing strength, and does not require cutting, so there is no wastage of material. There is no need to consider cross-sectional dimensions that are larger than necessary for the design.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of a dog type clutch, Fig. 2 is a perspective view of one clutch of the present invention and a sectional view of the cylindrical surface of the dog portion, and Fig. 3 is a dog portion forming a columnar body with no slope. FIG. 4a is a sectional view of a conventional dog part formed by cutting, FIG. 4b is a sectional view of a reverse slope dog part of the present invention, and FIG. A cross-sectional view of the body, and b is a cross-sectional view showing the state in which it is swaged and pressed in the direction of the arrow with a reverse gradient dog mold.
Similarly, c is a cross-sectional view showing the state of reverse gradient dog forming;
FIGS. 6 a, b, and c are sectional views showing a method of inserting the non-gradient columnar body into a mold and pressing the bottom part from below as shown by the arrows; FIGS. 7 a, b, and c.
8A and 9B are sectional views showing the processing order of another embodiment, and FIGS. 8A and 9B and 9A and 9B are sectional views showing two embodiments in which the molded dog part is removed from the mold. , Fig. 10 and 11 are both plan views showing the opening direction of the mold, Fig. 12 is a plan view of the main parts of the mold, Fig. 13 is a perspective view as well, and Fig. 14 is the press lowering operation during molding. 15 is a longitudinal sectional view taken along the line X-X of the entire device, FIG. 15 is a longitudinal sectional view also showing the pressurized state, FIG.
FIG. 7 is a longitudinal sectional view showing the state in which the product is removed, FIG. 18 is a plan view of the movable mold part at that time, FIG. 19 is a longitudinal sectional view of the entire apparatus at the start of the molding process of another embodiment, and The figure is also a longitudinal cross-sectional view of the state during processing,
FIG. 21 is a partially cutaway plan view of the movable mold section at that time. 2... Reverse slope dog part, 3... Intermediate molded product, 4
... Non-gradient dog part, 5, 6... Reverse gradient mold.

Claims (1)

[Scope of Claims] 1. In order to match the required reverse slope dog dimensions, taking into consideration the circumference at the time of finishing, the side surface of the clutch body is made slightly taller than the required reverse slope dog size, and the width is set to the minimum width. The combined non-gradient dog pillars are molded, and the pillars are set together in a movable reverse slope dog part forming mold, and the pillars are seated in the height direction and compressed. After the head of the dock is expanded and molded to form a reverse slope dock part, one or both of the reverse slope surface molding parts of the mold that are in contact with the reverse slope surface are moved in the width direction of the dock part to form the reverse slope dock part. A method for forming a reverse slope dog part of a dog type clutch, characterized in that the dog parts are moved apart from each other by more than the maximum width of the head, the reverse slope restraint is released, and the molded dog part is released from the molding die. . 2. Taking into consideration the dimensions of the finished product, a non-gradient dog column with a height slightly lower than the required reverse gradient dog dimensions and a width that matches its maximum width is molded as an intermediate product on the side of the clutch body, and this can be divided into movable parts. Set the columnar bodies together in a reverse gradient dog mold,
After forming the required reverse slope dog by inserting it in the width direction and compressing it so as to squeeze the root part to extend the length, move one or both of the reverse slope forming parts of the mold that are in contact with the reverse slope surface in the dog width direction. A method for molding a reverse slope dog part of a dog type clutch, characterized in that the molded dog part is removed from the mold by moving and releasing the reverse slope restraint. 3. A fixed part whose main body is a disc with a through hole for knockout in the center. Cutouts are provided on the disc according to the required number of dogs, and a movable part is placed in the cutout, and the molding During processing, a vertically movable punch section is provided with a ring body that circumscribes the movable mold part and holds it in a fixed position, and the fixed mold part is provided with a punch part for forming a reverse slope dog part concentrically with the through hole. The die cavity of the mold is recessed, the die cavity includes one side of the reverse slope molding, and the other side of the opposing side of the reverse slope molding is located in an opening communicating with the notch, and each of the notches The movable mold part is biased and pivoted to a fixed position that closes the opening, and the one reversely sloped molded side surface is formed to complement the molded part, while the punch part is attached to the molded part. A device for forming a reverse slope dog part of a dog type clutch, comprising a punch body that applies a pressing force to an intermediate molded product in which a dog part is aligned with a carved part, and a knockout pin that can freely move in and out of the ring body and the through hole.