JPH0741335B2 - Method for forming ears of sheet metal poly V pulley - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming an ear portion of a sheet metal poly-V pulley, and more specifically, to prevent the poly-V belt from coming off at one end of the outer peripheral wall where the poly-V groove is formed. To form a ring-shaped ear portion that projects radially outward.

[0002]

2. Description of the Related Art The applicant of the present invention has filed Japanese Patent Application No. 1-507920.
The following method has been proposed as a method for forming the ears of a sheet metal poly-V pulley. This method uses the bottom wall at the end of the bottom wall.
A cup-shaped material made of sheet metal integrally formed with an outer peripheral wall extending in a direction orthogonal to is covered with a rotary inner die for supporting the inner surface of the outer peripheral wall, and within the range of the thickness of the bottom wall of the material. To the root portion of the corresponding outer peripheral wall, while biting the root portion of the outer peripheral wall into two from the outer side while rotating the V-shaped ear molding projection formed on the roller surface of the outer rotating mold, This is a method of forming an annular ear portion projecting outward in the radial direction for preventing the poly V belt from coming off at one end portion of the outer peripheral wall where the poly V groove is formed.

[0003]

[Problems that the Invention is to Solve such ear portion forming side
The method is described in, for example, Japanese Patent Publication No. 64-11377.
The ear formation method that has been practiced before that
Method, that is, the connection between the outer peripheral wall and the bottom wall of the cup-shaped material
Place the contact parts so that the inner surfaces of both wall parts are crimped together.
Clamping process to form ears that project outward in the radial direction
Compared with the method, the required length of the material is less, and
It is possible to reduce the strike and tortoises when clamping the both walls.
Eliminates the problem of tearing and weakening of the ear
It has the advantage that it can. However, according to this conventional method, even if bite into V-shaped ears forming projections of the rotating outer die to the root source unit <br/> amount of the outer peripheral wall, ears facing radially outward of the outer peripheral wall The amount of protrusion depends on the thickness of the outer peripheral wall and the strength of the pulley.
The amount of protrusion of the poly V belt is
It was found that the prevention function could not be sufficient .

[0004] The present invention has been made in view of the above circumstances, even without increasing the wall thickness, when allowed to bite into the ear portion forming projection of the rotating outer die to the root original portion of the outer peripheral wall, predetermined belt
It has a sufficient amount of protrusion to ensure the retaining function.
And to provide a sheet metal poly-V pulley ear part forming method that can <br/> in is possible to reliably form the ear portion radially outward of the outer peripheral wall.

[0005]

[Means for Solving the Problems] To achieve the above object
According to the method of forming the ears of the sheet metal pulley according to the present invention , a ring-shaped ears protruding outward in the radial direction is formed at one end of the outer peripheral wall to prevent the poly V belt from coming off. In, the outer peripheral wall is formed so that the diameter of the tip end side portion is smaller than that of the root portion, and then the outer peripheral wall is rotated.
The upper and lower holding surfaces of the rotating inner mold cover the above
By attaching sandwiched the outer peripheral wall to form a space between the root portion of the outer peripheral wall and rotated in a mold, while rotating the rotating outer die in this state, the roots original portion of the outer peripheral wall in rotating outside type Sky
Press it against the inner mold side to deform it so that there is no gap.
While, outside the V-shaped ears formed protrusions which are provided to the rotating outer die
By cutting into the root portion of the peripheral wall, an annular ear projecting the root source portion have split radially outward into two from the outside
It is characterized by forming a part .

[0006]

According to the present invention, the tip side portion is more than the root portion.
The rotating inner mold is covered with the outer peripheral wall of the tip constriction shape that is molded so that the diameter becomes small, and the upper and lower clamping surfaces of the inner mold rotate.
Put sandwiched, form a space between the rotary inner mold and its root source portion
The outer peripheral wall root part with a rotating outer mold.
Press to the inner mold side to transform it so as to eliminate the storage space.
However, the V-shaped ear molding projection provided on the outer rotating mold
After forming the ears by cutting into the root of the peripheral wall
A large amount of radial outward projection of the outer peripheral wall of the
Then , the ear portion can be sufficiently projected outward in the radial direction without increasing the thickness of the outer peripheral wall .

[0007]

Next, a method of manufacturing a sheet metal poly-V pulley adopting an embodiment of the present invention will be described for each step. A flat plate-like material (not shown) as a starting material has the same thickness as that required for the outer peripheral wall 13 provided with the poly V groove 15 in the sheet metal poly V pulley to be manufactured. There is.

A. First Drawing Step This step is a step of forming a bottom wall-corresponding portion 1 and a peripheral wall-corresponding portion 2 by squeezing a flat plate material, which is a starting material, by an inner die 100 and an outer die 200 as shown in FIG. Then, in the peripheral wall equivalent portion 2, an inner peripheral wall equivalent portion 3 which becomes an inner peripheral wall 10 for bearing press-fitting of a sheet metal poly-V pulley to be manufactured, and a tip portion of the inner peripheral wall equivalent portion 3 is projected outward. An outer peripheral wall equivalent portion 4 that becomes the outer peripheral wall 13 provided with the groove 15 is provided. Hat-shaped material formed by going through this first drawing process
The bottom wall equivalent portion 1 and the inner peripheral wall equivalent portion 3 of W are thinned. Specifically, when using a flat plate material with a wall thickness of 2.8 mm,
The bottom wall-corresponding portion 1 has a wall thickness of about 2.6 mm, and the inner peripheral wall-corresponding portion 3 has a wall thickness of about 1.8 to 2.1 mm. In many cases, the wall thickness of the outer peripheral wall equivalent portion 4 does not change. The aperture depth is set to 15.1 mm.

B. Drilling Step In this step, as shown in FIG. 2, the inner die 101 and the punch 201 are used to open a hole 5 in the center of the bottom wall corresponding portion 1. The hole 5 formed in this process is to be machined into the shaft hole 16 in the subsequent process, and the inner diameter of the shaft hole 16 is 3 mm.
When 1.0 mm is required, the inner diameter of the hole 5 may be set to 15.7 mm, which is about half the inner diameter. 6 is a scrap produced by drilling, this scrap 6 has been punched from the thinned bottom wall equivalent portion 1, and by punching out the hole portion 5 which is about half the size of the shaft hole 16. Since it has occurred, the amount is extremely small.

C. Second drawing step This step is the hat element that has undergone the perforating step described in FIG.
The bottom wall equivalent part 1 and the inner peripheral wall equivalent part 3 of the material W are further squeezed by using the inner mold 102 and the outer mold 202 as shown in FIG. 3, thereby expanding the diameter of the hole 5 of the bottom wall equivalent part 1. It is a process. In the hat-shaped material W that has been subjected to the second drawing step, the bottom wall equivalent portion 1 and the inner peripheral wall equivalent portion 3 are continuous via the radius portion 7 having a relatively large radius of curvature, and the radius portion 7 is meat. The thickness is reduced to about 1.6 to 1.7 mm. Also,
The inner peripheral wall equivalent portion 3 is thinned to about 1.6 to 1.7 mm.

D. Handling step This step is a step of further narrowing down the inner peripheral wall corresponding portion 3 narrowed in the second narrowing step to adjust its shape. Therefore, this handling step can be said to be the third drawing step performed subsequent to the second drawing step, and the first handling step shown in FIG. 4 and the second handling step shown in FIG. Contains.
By passing through this step, the corner portion 8 of the hat-shaped material W is formed at the boundary portion between the bottom wall-corresponding portion 1 and the inner peripheral wall-corresponding portion 3 at a right angle or near a right angle. That is, in the first handling step of FIG. 4, the radius of curvature of the rounded portion 7 shown in FIG. 3 is slightly reduced by the inner die 103 and the outer die 203, and then,
By performing the second handling step of FIG. 5, the rounded portion 7 of the inner die 104 and the outer die 204 is shaped as a corner portion 8 which is closer to a right angle, and at the same time, the bottom wall equivalent portion 1 is formed on the bottom wall 9. The inner peripheral wall equivalent portion 3 is formed on the inner peripheral wall 10.

The inner mold 104 used in the second handling step is
The molding surface 105 having a uniform outer diameter is provided, and the molding surface 105 of the inner mold 104 is covered with the inner peripheral wall corresponding portion 3 of the hat-shaped material W. In addition, the outer mold 204 corresponding to the inner mold 104
Indicates that the inner diameter of the pressing surface 205 with respect to the inner peripheral wall equivalent portion 3 of the hat-shaped material W covered by the inner mold 104 is the boundary portion of the inner peripheral wall equivalent portion 3 with the bottom wall equivalent portion 1, that is, the inner peripheral wall equivalent portion 3. The diameter increases as it moves away from the portion that presses the base end portion (corresponding to the corner portion 8) in the axial direction. When the inner peripheral wall 10 is formed by handling the inner peripheral wall equivalent portion 3 of the hat-shaped material W covered with the inner mold 104 by using the outer mold 204, the formed inner peripheral wall 10 has a corner which is the base end thereof. The thicker it is, the further away from the part 8. That is, in the hat-shaped material W that has undergone the second handling step, the corner portion 8 and the inner peripheral wall 10 in the immediate vicinity thereof have a wall thickness of about 1.7 mm, and the portion immediately near the tip of the inner peripheral wall 10 has a wall thickness of about 2.1 mm. Become. Then, it was confirmed that the inner diameter of the inner peripheral wall 10 was finished uniformly even if the hat-shaped material W was released from the mold. Therefore, when the bearing is press-fitted into the inner peripheral wall 10, a misalignment between the bearing and the pulley does not occur, and the bearing can be surely inserted to a predetermined position. In FIG. 5, the difference in the wall thickness of each axial portion of the inner peripheral wall 10 is exaggerated.

E. Finishing process of the portion corresponding to the outer peripheral wall This process is performed as shown in FIG.
7 is a step of cutting and removing the outer peripheral edge of the outer peripheral wall corresponding portion 4. 11 is a scrap produced by the cutting .

F. Reverse drawing step In this step, as shown in FIG. 7, the outer peripheral wall equivalent portion 4 of the hat-shaped material W put on the inner molds 108 and 109 and sandwiched between the outer molds 209.
The outer peripheral wall 1 is concentric with the slanted annular portion 12 and the inner peripheral wall 10 by being folded back at.
3 is a step of forming.

G. Bulge step In this step, as shown in FIG. 8, the inner die 110 is covered with the hat-shaped material W that has undergone the reverse drawing step described in FIG. 7, and the tip of the outer peripheral wall 13 is attached to the supporting surface 111 provided in the inner die 110. to support the surface is a step to expand the boundary portion between the outer peripheral wall 13 and the annular portion 12 by pressing the annular portion 12 in the outer mold 210 from this state, that is, the root original portion of the outer peripheral wall 13 outwardly. The outer peripheral wall 13 of the hat-shaped material W that has undergone this step is formed into a shape with a narrowed tip so that the tip side portion is smaller in diameter than the root portion, and in some cases, is thickened at the same time.

H. Ear portion forming step This step is a step of forming a single layer annular ear portion 14 at the intersection of the outer peripheral wall 13 and the annular portion 12. This step is performed as follows. That is,挾rotary inner die 112 and 113 simultaneously Ru covered the hat-shaped material W which has undergone the bulge process, the outer peripheral wall 13 in the upper and lower pair of clamping surfaces 114 and 115 of the rotating inner die 112 and 113 as shown in FIG. 9 Find. In this way, the hat-shaped material W is rotated by the inner mold 112,
When it is put on 113, the root portion of the outer peripheral wall 13 and the rotating inner mold 1
A space S narrowing toward the tip side is formed between the space S and the space 12.

While rotating the outer rotating mold 213 in this state, as shown in FIG. 10, the root portion of the outer peripheral wall 13 is pressed against the inner rotating mold 112 side to deform so that the space S disappears , and the root of the space S disappears. The ear forming projection 214 provided on the outer rotating mold 213 is bitten from the outside so as to divide the original portion into two parts. In this way, the root original portion of the outer peripheral wall 13 of the sandwiched Tagged tip Subomari shape clamping surfaces 114 and 115 of the rotating inner die 112 and 113, radially outward by the deformation when eliminating the space S The amount of material flowing to the outer peripheral wall 13 increases, and the amount of protrusion of the ear portion 14 from the outer peripheral wall 13 becomes sufficiently large. The outer peripheral wall 13 that has undergone this step is thickened to a thickness of about 2.9 mm.

I. Poly V Groove Forming Step This step is a step of forming the poly V groove 15 on the outer peripheral wall 13. In this step, as shown in FIG. 11, FIG. 12 or FIG. 13, the hat-shaped material W is sandwiched between the inner rotating dies 112, 113, and the outer wall 13 has a poly-V groove 1 formed of a plurality of V groove groups.
5 is formed by rolling and forming the poly V groove 15. The poly V groove 15 is formed by the preliminary poly V groove forming step and the preliminary poly V groove forming step more than in the case of forming by one rolling. It is preferable that the poly V groove of the outer peripheral wall 13 that has been subjected to the rolling is further subjected to rolling, and a finishing step of finishing the depth and pitch thereof as required is performed by plural times of rolling forming.

This step is performed by rotating the inner mold 11 as shown in FIG.
The molding surface 116 of No. 2 and the molding surface 216 of the outer rotary mold 215 both have valleys and peaks alternately and are formed to be meshable with each other, or FIG.
1 and FIG. 12, the molding surface 116 of the inner rotating mold 112 is a flat surface in the vertical direction and the molding surface 216 of the outer rotating mold 215.
What is formed may be used, what is formed in the uneven | corrugated surface which has a valley part and a peak part alternately. When the method of FIG. 13 is adopted, a sheet metal poly V pulley having a poly V groove 15 on the outer surface side and an outer peripheral wall 13 having an uneven inner surface is manufactured. When the method of FIGS. 11 and 12 is adopted, a sheet metal poly V pulley having a poly V groove 15 on the outer surface side and an outer peripheral wall 13 whose inner surface is straight in the vertical direction is manufactured.

J. Centering Step This step is a step of centering the inner peripheral wall 10 and the outer peripheral wall 13 by using the inner mold 117 and the outer mold 217 as shown in FIG.

K. Shaft Hole Finishing Step This step is performed in the inner die 118 and punch 218 as shown in FIG.
This is a step of cutting and removing the peripheral edge portion of the hole portion 5 whose diameter has been increased by using and to finish the shaft hole 16. 17 is a scrap produced by the cutting .

In the embodiment described above, the shaft hole 16 formed by expanding the diameter of the hole 5 may have the same inner diameter as the inner diameter of the inner peripheral wall 10. That is, it is also possible to manufacture a sheet metal pulley in which the opening portion of the inner peripheral wall 10 serves as a shaft hole without the bottom wall 9.

[0023]

As described above , according to the present invention, the distal stenosis
Clamp the ball-shaped outer wall with the upper and lower clamping surfaces of the rotating inner mold
To form a space between the root part and the rotating inner mold.
In this state, rotate the root of the outer peripheral wall and use the outer mold to create the above space.
While pressing against the rotating inner mold side to deform so as to lose,
Insert the outer molding ear protrusion into the root of the outer peripheral wall.
The outer peripheral surface of the outer peripheral wall after forming the ears by
The amount of protrusion to the outside in the radial direction is increased to increase the thickness of the outer peripheral wall.
Even if you do not increase it separately, you can ensure the predetermined belt detachment prevention function.
Secure the ear with a sufficient amount of protrusion to make it really effective
The effect that it can be formed in.

[Brief description of drawings]

FIG. 1 is a sheet metal poly-V pulley adopting an embodiment of the present invention .
FIG. 6 is an explanatory view of a first drawing step in the manufacturing method of FIG.

FIG. 2 is an explanatory diagram of a drilling step in the above manufacturing method .

FIG. 3 is an explanatory diagram of a second drawing step in the above manufacturing method .

FIG. 4 is an explanatory diagram of a first handling step in the above manufacturing method .

FIG. 5 is an explanatory diagram of a second handling step in the above manufacturing method .

FIG. 6 is an explanatory diagram of a finishing step of a portion corresponding to the outer peripheral wall in the manufacturing method of the above .

FIG. 7 is an explanatory diagram of a reverse drawing step in the above manufacturing method .

FIG. 8 is an explanatory diagram of a bulge process in the above manufacturing method .

FIG. 9 is an explanatory diagram of an ear portion forming step in the above manufacturing method .

FIG. 10 is an explanatory diagram of an ear portion forming step in the above manufacturing method .

FIG. 11 is an explanatory diagram of a poly V groove forming step in the manufacturing method same as above .

FIG. 12 is an explanatory diagram of a poly V groove forming step in the same manufacturing method as above .

FIG. 13 is an explanatory diagram of a poly V groove forming step in the manufacturing method same as above .

FIG. 14 is an explanatory diagram of an aligning step in the above manufacturing method .

FIG. 15 is an explanatory diagram of a shaft hole finishing step in the above manufacturing method .

[Explanation of symbols]

 13 outer peripheral wall 14 ears 112,113 rotation inner mold 114,115 holding surface 213 rotation outer mold 214 ear molding protrusion S space

Claims (1)

[Claims] 1. A method of forming an annular ear portion protruding outward in the radial direction for preventing the poly V belt from coming off at one end of the outer peripheral wall, wherein the outer peripheral wall has a root portion. after the distal portion than is molded into a smaller diameter, this
The outer peripheral wall of the rotary inner mold is covered with the upper and lower parts of the rotary inner mold.
By sandwiching the outer peripheral wall with a pair of sandwiching surfaces, a space is formed between the root portion of the outer peripheral wall and the rotary inner die ,
While rotating the rotary outer die in a state, while deforming pressed against the rotating inner die side so that the space is eliminated the root portion of the outer peripheral wall in rotating outside type, V-shaped ears which are provided to the rotating outer die Make the forming protrusion cut into the root of the outer peripheral wall.
The radially outward had split into two from the outside the root source portion
A method for forming an ear portion of a sheet-metal poly-V pulley, which comprises forming an annular ear portion that protrudes to the outside.