JP3060290B2 - Sheet metal pulley and manufacturing method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet metal pulley used for an electromagnetic clutch and the like, and a method of manufacturing the same.

[0002]

2. Description of the Related Art A circular shoulder portion is concentrically connected to a cylindrical portion, and a body wall of a pulley main portion having a single or a plurality of annular V-grooves on its outer peripheral portion is formed concentrically on the shoulder portion. 2. Description of the Related Art Continuously provided sheet metal pulleys are conventionally known. When a disk made of a metal plate such as a steel plate is used as a starting material of the sheet metal pulley, a preformed body, specifically, a circular shoulder portion is formed in a cylindrical portion by performing a certain type of machining on the disk. After forming a sheet metal preform formed concentrically and having a cylindrical body wall continuously provided at the shoulder, a forming roller is provided on the outer peripheral portion of the body wall in the preform. The V-groove forming surface is pressed to form a V-groove.

[0003]

FIG. 7 shows that the cylindrical body wall 32 of the preformed body is attached to a rotary mold 95, and the body wall 32 is rotated together with the rotary mold 95.
2 shows a step of pressing a V-groove forming surface 96 a provided on the press-forming roller 96 against the outer peripheral portion of No. 2 to form a V-groove 97. However, if the V-groove forming surface 96a of the press-forming roller 96 is simply pressed against the outer peripheral portion of the cylindrical body wall 32, the valley portion 97a and the crest portion 97b of the V-groove 97 are formed due to the flow of meat accompanying the pressing. As shown by the arrow a in FIG. 7, the flesh flow generated on the body wall 32 collides with the body wall 32 and the shoulder 2 and presses against each other as shown in FIG. A phenomenon occurs and the press forming roller 9
When the V-groove forming surface 96a of No. 6 was separated from the body wall 32, there was a case where cracks were generated which were presumed to be caused by the pressing.

The present invention has been made in view of the above circumstances, and is intended to form a V-groove by pressing a V-groove forming surface of a forming roller against an outer peripheral portion of a body wall of a preform mounted on a rotary mold. Another object of the present invention is to provide a method of manufacturing a sheet metal pulley which does not cause a crack caused by a meat flow generated on a body wall, and a sheet metal pulley which can be manufactured by such a method.

[0005]

The invention according to claim 1 is
The present invention relates to a sheet metal pulley, and the feature thereof is that a circular shoulder 2 is concentrically connected to a cylindrical portion 1, and the shoulder 2 has
It is a sheet metal pulley in which a body wall 32 of a pulley main portion 3 having an annular poly-V groove 31 on an outer peripheral portion is provided concentrically and continuously, and is connected to the shoulder portion 2 on the body wall 32. Is formed on a curved surface 33 which bulges inward, and is formed at the end of the poly-V groove 31 by the outer peripheral surface of the connecting portion b.
A valley bottom surface 34 concaved in an arc shape of one V-groove located is formed, and a ridge top surface 35 projecting in an arc shape adjacent to the valley bottom surface 34 is formed on the curved surface 33. It is formed at a position corresponding to the axial end 33a of the body wall 32 in the radial direction D of the body wall 32 (see FIGS. 5 and 17).

The sheet metal pulley can be used as a mounting portion for connecting the cylindrical portion 1 to a rotary input shaft or as a mounting portion for connecting the cylindrical portion 1 to a rotor of an electromagnetic clutch. . The sheet metal pulley has a curved surface 33 in which the inner peripheral surface of the continuous portion a, which corresponds to the bottom surface 34 of the V-groove, bulges inward.
And a circle adjacent to the valley bottom surface 34.
The crest 35 protruding in an arc shape is an end of the curved surface 33.
(That is, the end of the curved surface 33 in the axial direction of the trunk wall 32: bay
(The axial end of the trunk wall 32 on the curved surface 33) 33a
On the other hand, it is formed at a position corresponding to the body wall 32 in the radial direction D.
It is possible to avoid that the portion corresponding to the bottom surface 34 of the V-groove becomes too thin to cause insufficient strength.
Wear. (See FIGS. 5 and 17).

[0007] The invention according to claims 2 to 4 relates to a method for producing a sheet metal pulley, of which, according to
In the invention according to Item 2 , a circular shoulder portion 2 is concentrically connected to the cylindrical portion 1, and a cylindrical trunk wall 32 is connected to the shoulder portion 2 ,
At the location where the body wall 32 and the shoulder portion 2 are continuously connected,
Sheet metal having a cross section curved preliminary valleys 36 that selfish bulged
Of a sheet metal pulley using a preform B made of
It, valleys forming surface and mountain portion forming surface of the valley of the mountain-shaped and is axially
One valley located at the end of the poly V groove forming surface 89 aligned with
So that the part forming surface 89a does not hit the preliminary valley 36.
Section from another valley molding surface while being opposed excluding the preliminary valleys 36 by Rukoto pressed against the outer circumferential surface of the body wall 32
A rough poly V groove 31a is formed in
Pressing the preliminary valley 36 with the molding surface 89a,
A pulley main portion having a poly-V groove in which the formation portion of the preliminary valley portion 36 is one of the valley portions is formed (see FIGS . 2 , 4, and 6 ).

[0008] According to the manufacturing method of the present invention, the aforementioned connecting設箇
A poly-V is formed on the outer peripheral surface of the body wall 32 without causing a crack
It becomes possible to manufacture a sheet metal pulley having a groove.
That is, one of the poly V-groove molding surfaces 89 located at the end
The valley forming surface 89a should not hit the preliminary valley 36.
The other valley forming surface is positioned outside the body wall 32 in a state where
A part excluding the preliminary valley part 36 by pressing against the peripheral surface
A coarse poly-V groove 31a is formed in the
By pressing the preliminary valley portion 36 with the part forming surface 89a,
Poly-Polymer having one trough at the place where the above-mentioned preliminary trough 36 is formed
Since the main portion of the pulley provided with the V-groove is formed, the preliminary valley portion 36 is formed.
No pressing occurs due to the collision of the meat flow that causes cracks in the plate (see FIGS . 2 , 4 and 6 ).

According to a third aspect of the present invention, in the second aspect , the preform is formed by using the disc 100 as a starting material, and the preform is formed on the body wall 32 of the preform B. Prior to forming the valley portion 36, the trunk wall 32 is thickened (see FIGS. 2, 4 and 8).

According to the manufacturing method of the present invention, a thin disk 100 can be used as a starting material.

[0011]

FIG. 17 is a sectional view of a sheet metal pulley A according to the present invention.
Is enlarged for explanation.

In this sheet metal pulley A, a circular inclined shoulder 2 whose diameter gradually decreases as the distance from the cylindrical part 1 increases is concentrically connected to the cylindrical part 1. A trunk wall 32 of the pulley main part 3 having a V-groove 31 on the outer periphery is provided concentrically. As shown in FIG. 5, the inner peripheral surface of the connecting portion a with the shoulder portion 2 on the body wall 32 is formed into a curved surface 33 bulging inward, and the outer peripheral surface of the connecting portion a A valley bottom surface 34 concaved in an arc shape of the poly V groove 31 is formed. Furthermore, the valley bottom 3
An arc-shaped ridge top surface 35 of the poly V-groove 31 adjacent to the upper surface 4 is formed with respect to an end 33 a of the curved surface 33 in the axial direction (arrow C) of the body wall 32. In the radial direction (arrow D).

The sheet metal pulley A serves as a mounting portion for connecting the cylindrical portion 1 to a rotary input shaft (not shown) or for connecting the cylindrical portion 1 to a rotor (not shown) of an electromagnetic clutch. Used as a mounting part for At this time, a hole (not shown) may be formed in the cylindrical portion 1, and a fastening bolt (not shown) inserted into the hole may be connected to the rotary input shaft or the rotor. Further, regarding the sheet metal pulley A,
At the above-mentioned continuous portion a, the bottom surface 34 of the valley portion of the poly V groove 31
The thickness of the portion corresponding to the above-mentioned is because the inner peripheral surface of the continuous portion a is the curved surface 33 as described above,
It can be avoided that a portion corresponding to the bottom surface 34 of the groove 31 of the groove 31 becomes thinner and causes insufficient strength.

FIGS. 1 to 3 are explanatory views showing steps of manufacturing the above-mentioned sheet metal pulley A using a sheet metal preform B. FIG. FIG. 12 shows a cross section of the original shape of the preform B.

As shown in FIG. 12, the original shape of the preform B is
A circular inclined shoulder 2 whose diameter gradually decreases as the distance from the cylindrical portion 1 increases is concentrically connected to the cylindrical portion 1, and a cylindrical body wall 32 is connected to the shoulder 2. This shoulder 2 may be formed horizontally.

FIG. 1 shows a step of increasing the thickness of the body wall 32 of the preform B and a step of forming a preliminary valley 36 at a location where the body wall 32 and the shoulder 2 are connected. . In these steps, a rotary lower die 81 and a rotary upper die 82 are used. The lower rotary mold 81 and the upper rotary mold 82 form a concave portion 84 that straddles the two dies 81 and 82, and an annular concave molding surface 85 is formed on the outer peripheral portion of the mating surface 83 of the two dies 81 and 82. Form.

In the first stage of the process shown in FIG.
After the trunk wall 32 of the preform B of original as described in 2 was deployed in the recess 84 between the rotary lower mold 81 and the rotary upper mold 82, to rotate the preform B with both types 81 and 82 Meanwhile, the body wall 32 is pushed into the concave portion 84 by the press forming roller 86 having the concave forming surface 86a shown in the left half of FIG. In this case, the vertical width of the recessed portion 84 is
It is shorter than the height of the body wall 32. Therefore, the body wall 32 is pushed into the concave portion 84 by the press forming roller 86 while being bent as shown in the left half of FIG. At the stage after the process shown in FIG. 1, the torso wall 32 which has been pushed into the concave portion 84 and bent is further pushed into the concave portion 84 by the press forming roller 87 shown in the right half of FIG. The press forming roller 87 has a tapered forming surface 87a and a protruding forming surface 87b provided at a lower end thereof. Therefore, the portion of the body wall 32 pressed by the forming surface 87a is thickened, and the portion pressed by the forming surface 87b against the concave forming surface 85 is formed into the preliminary valley portion 36 having a curved cross section. Is done. Here, the thickness of the body wall 32 is increased prior to the formation of the preliminary valley portion 36.

FIG. 4 is an enlarged view of a main part of a preform B formed by the steps described with reference to FIG. In this preform B, the trunk wall 32
The thickness becomes thicker as approaching the connecting portion A between the body wall 32 and the shoulder portion 2, and the inner surface excluding the connecting portion A is finished to a surface 38 having no irregularities. At the upper end portion, a preliminary ear portion 37 which protrudes outward is formed, and is formed at the continuous portion a by the cooperation of the protruding forming surface 87b of the press forming roller 87 and the recess forming surface 85. The above-mentioned preliminary valley portion 36 is formed. The preliminary valley 36 is curved inward. Also, the torso wall 32
Is thicker than the body wall 32 described with reference to FIG. 12, and the wall thickness T2 (for example, 1.1 to 1.2 mm) of the continuous portion A is also described with reference to FIG. The thickness is larger than the thickness T1 of 32 (for example, 0.8 mm). The taper angle θ of the outer peripheral surface of the body wall 32 is approximately 30 degrees.

FIG. 2 shows a step of roughly forming the main part of the pulley. In this step, a press forming roller 88 is used. The press forming roller 88 has a valley forming surface 89 having a chevron shape.
a and a valley-shaped peak forming surface 89b have a poly-V groove forming surface 89 that is alternately continuous. This press forming roller 88 is
As shown in the right half of FIG. 2, the lower rotating die 81 and the upper rotating die 82
When the body wall 32 is pressed against the thickened body wall 32 attached thereto, a rough poly V groove 31a as shown in the left half of FIG. 2 is formed in the body wall 32.

FIG. 6 illustrates the first stage of the process of FIG. 2 described above. As can be seen from FIG. 6, since the preliminary valley portion 36 is formed in a curved shape in advance at the continuous portion A between the body wall 32 and the shoulder portion 2, the press forming roller 8 is formed.
At the first stage when pressing 8 against the body wall 32,
The poly V groove forming surface 89 of the press forming roller 88 does not hit the preliminary valley portion 36. Only after the portion of the trunk wall 32 other than the preliminary valley portion 36 is pushed by the V-groove forming surface 89 and the coarse poly-V groove 31a is formed in that portion, the poly-V groove forming surface 89 becomes the preliminary valley portion 36. , The preliminary valley portion 36 is pushed. For this reason, the poly V groove forming surface 89
When the rough poly V groove 31a is formed in the body wall 32 by pressing against the outer peripheral surface of the body wall 32 to generate a flesh flow in the body wall 32, the preliminary valley 36 No pressing occurs due to the collision of the meat flow that causes cracks in the plate. Therefore, the press forming roller 8
When the poly-V groove forming surface 89 of FIG. 8 is separated from the body wall 32, cracks B (see FIG. 7) do not occur.

FIG. 3 shows a finishing process of the pulley main portion 3. In this step, a rotating lower die 91 having a curved forming surface 91a for forming a large number of curved portions on the inner surface of the body wall 32 and a corresponding rotating upper die 92 are used, and a finishing poly-mold is used. V-groove molding surface 93a and ear molding surface 9
3b is used. The rotary lower die 91 is an eccentric type. As shown in the right half of FIG.
Coarse V-groove 31 attached to the upper die 92
a (see FIG. 2), it is finished into a poly-V groove 31 as shown in the left half of FIG.

Through the above steps, the sheet metal pulley A described with reference to FIG. 17 is manufactured.

FIGS. 8 to 17 are sectional views showing various shapes of the starting material when the starting material is formed on the sheet metal pulley A. FIG. 8 shows a disk 100 as a starting material, and its thickness T is the same as that of the preform A described in FIG.
Is between the thickness T1 of the body wall 32 and the thickness T2 of the body wall 32 after the increase in thickness described with reference to FIG. 8 is drawn and formed into a cup-shaped material 110 as shown in FIG. 9, and the top plate portion 111 of the cup-shaped material 110 is drawn.
The hole-shaped cup-shaped material 1 shown in FIG.
20 are formed. Next, a stretching process is performed on the perforated cup-shaped raw material 120 of FIG. 10 to form a rough formed body 130 as shown in FIG. 11, and the lower end of the rough formed body 130 is trimmed to form B is obtained.
The preform B is subjected to the steps described with reference to FIG. 1 so that the trunk wall 32 of the preform B is bent as shown in FIG. 13 and then the thickness of the trunk wall 32 is increased as shown in FIG. You. The process described with reference to FIG. 2 is performed on the body wall 32 that has been increased in thickness in this manner, and as shown in FIGS.
1a is formed, and the coarse poly V-groove 31a is subjected to the steps described with reference to FIG.
Finished.

In the above-described embodiment, the shape of the inner surface of the body wall 32 of the pulley main portion 3 in the sheet metal pulley A corresponds to the valley portion 31b of the poly V groove 31, as shown by the imaginary line in FIG. The curved surface 33b bulges inward at the location, and the end of each curved surface 33b is located at a location corresponding to the peak 31c of the poly V groove 31 in the radial direction of the body wall 32. Therefore, the body wall 32 does not become thinner at a portion corresponding to the valley portion 31b of the poly-V groove 31. Therefore, the trunk wall 3
A crack is unlikely to occur in a portion corresponding to the valley of the poly V groove 31 in FIG. Moreover, as can be seen in FIG.
Since the preliminary valley portion 36 indicated by the solid line corresponds to the valley portion 31b of the poly-V groove 31 formed at the connecting portion a,
It is easy to increase the thickness T2 of the trough 31b by increasing the thickness thereof.

[0025]

According to the sheet metal pulley of the present invention, even if a valley bottom surface of the V-groove is formed at a continuous portion between the trunk wall of the pulley main portion and the circular shoulder portion, the valley bottom surface is formed. It is possible to increase the strength by securing a sufficiently thick wall at the formation location. Therefore, there is an effect that it is possible to make it difficult for cracks to be generated in the above-mentioned connected portion where stress concentration is likely to occur.

According to the method of manufacturing a sheet metal pulley according to the present invention, the poly- V groove forming surface of the forming roller is pressed against the outer peripheral surface of the trunk wall of the preform to form the poly-V groove on the outer peripheral surface of the trunk wall. Despite adopting the method described above, it is possible to prevent a crack from being generated at the connecting portion between the trunk wall and the shoulder.

In the method for manufacturing a sheet metal pulley according to the present invention, a preform is formed by using a thin disk as a starting material, and the body wall of the preform is thickened. If a method of forming a preliminary valley or a V-groove on a thick body wall is adopted, a thin-walled material can be machined by pressing or the like to form a preformed body. There is an advantage that processing becomes easier as compared with a case where a preform is made by using.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a step of thickening a body wall of a molded article and a step of molding a preliminary valley in an embodiment of the method of the present invention.

FIG. 2 is a cross-sectional view showing a step of forming a coarse poly-V groove in a body wall in the embodiment of the method of the present invention.

FIG. 3 is a sectional view showing a finishing step in the embodiment of the method of the present invention.

FIG. 4 is an explanatory view comparing the shapes of each body wall of a preformed body and a sheet metal pulley.

FIG. 5 is an enlarged explanatory view of a main part of a sheet metal pulley,
This corresponds to an enlarged view of a portion V in FIG.

FIG. 6 is an explanatory diagram showing an initial stage of the process in FIG. 2;

FIG. 7 is an explanatory diagram for explaining a conventional problem.

FIG. 8 is a sectional view of a disk as a starting material.

FIG. 9 is a sectional view of a preliminary cup-shaped material.

FIG. 10 is a sectional view of a perforated preliminary cup-shaped material.

FIG. 11 is a sectional view of a preform.

FIG. 12 is a sectional view of a preform.

FIG. 13 is a sectional view of a preform.

FIG. 14 is a cross-sectional view of a preformed body in which a trunk wall is thickened and a pre-valley is formed.

FIG. 15 is a cross-sectional view of one in which a coarse poly-V groove is formed.

FIG. 16 is a cross-sectional view of one in which a coarse poly-V groove is formed.

FIG. 17 is a sectional view of a sheet metal pulley.

[Explanation of symbols]

 Reference Signs List A Sheet metal pulley a Place of connection with shoulder on body wall 1 Cylindrical part 2 Shoulder part 3 Pulley main part 31 Poly V groove (V groove) 32 Body wall 33 Curved surface 33a Axial end of body wall on curved surface 34 Valley bottom surface 35 Peak top surface 36 Preliminary trough 89 Poly V groove forming surface (V groove forming surface) 89a Valley forming surface 89b Peak forming surface C Axial direction of trunk wall D Radial direction of trunk wall

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F16H 55 / 44,55 / 49 B21H 1/06 B21D 15 / 06,53 / 26

Claims (3)

(57) [Claims] 1. A cylindrical shoulder is provided with a circular shoulder concentrically connected thereto, and a body wall of a pulley main portion having an annular poly-V groove on an outer peripheral portion is provided concentrically with the shoulder. A sheet metal pulley, wherein an inner peripheral surface of a connecting portion with the shoulder portion on the body wall is formed into a curved surface bulging inward, and the poly-V groove is formed by an outer peripheral surface of the connecting portion. One V located at the end of
A valley bottom that is concave in an arc shape of the groove is formed, and a ridge top surface that protrudes in an arc shape adjacent to the valley bottom is formed at an axial end of the trunk wall on the curved surface. A sheet metal pulley formed at a location corresponding to a radial direction of the body wall. 2. A circular shoulder in the cylindrical portion is provided continuously concentrically, the cylindrical barrel wall in the shoulder portion is continuously provided, the cylinder wall and the top
A section bay bulging inward at the point of connection with the shoulder
Plates using sheet metal preforms with curved pre-valleys
Gold A method of manufacturing a pulley, and mountain portion forming surface of the mountain-shaped valley molding surface and valley are aligned in the axial direction
One valley molding surface located at the end of the poly V groove molding surface
In the state of facing the above spare valley so as not to hit
The Rukoto pressing the valley forming surface on the outer peripheral surface of the cylinder wall
A coarse poly-V groove is formed in a portion excluding the above-mentioned preliminary valley portion.
Then, press the spare valley with the one valley molding surface
Then, the formation location of the above-mentioned preliminary valley is one of the valleys.
A method for manufacturing a sheet metal pulley, comprising forming a pulley main portion having a V groove . 3. The method according to claim 1, wherein the preform is formed using a disk as a starting material, and the body wall of the preform is thickened prior to forming the preliminary valley in the body wall. Item 2. A method for manufacturing a sheet metal pulley according to Item 2 .