JPH0324934Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is a sheet metal pulley rotation shaft end attachment device in which the pulley circumferential surface, rim portion, and pulley rotation shaft end attachment boss portion are integrally molded from a single plate material, and is integrally molded on the pulley. This invention relates to a shaft mounting device for a sheet metal pulley.

Conventionally, a shaft end attachment device for an integrally molded sheet metal pulley has been disclosed, for example, in Japanese Patent Publication No. 56-35779.
The boss part was formed into a cylindrical shape by drawing, and the shaft end was inserted into it, but when a thin sheet metal material is further drawn into a cylindrical shape, the wall thickness of the cylindrical part naturally becomes thinner, and the shaft end is inserted. When a bolt is inserted into the bottom of the cylindrical part to fasten the end and the pulley and prevent rotation, the bottom part cannot withstand the fastening and anti-rotation load and breaks. This resulted in a strength defect in that the strength for holding the peripheral surface was reduced and the pulley could no longer be reliably supported on the shaft end, and was not fully satisfactory as a shaft end mounting device for a sheet metal pulley.

In addition, the boss of the sheet metal pulley is made into an axially cut-and-raised pawl that fits onto the outer peripheral surface of the shaft end, but since the tip of the pawl is a free end, it securely holds the shaft end. It has the disadvantage that the strength of the process is weakened.

Furthermore, as disclosed in Japanese Utility Model Application Publication No. 56-59348, in order to increase the rigidity of the rim portion of a toothed sheet metal wheel, a plurality of protrusions are formed radially on the rim portion, and the protrusions are There is also a shaft mounting device in which the outer circumferential surface of the end of the mounting shaft is fitted with the upright end surface on the shaft center side, but the radial protrusion cannot be protruded by plastic working unless the rim is a flat or conical surface. Have difficulty. However, in order to achieve the desired axial mounting position of the toothed wheel relative to the mounting shaft end, it is necessary to axially adjust the formation position of the axis-perpendicular surface of the boss that regulates the mounting position. for,
A multi-stage annular conical drawing process is often performed on the rim part, but if protrusions are formed radially in the radial direction, it is difficult to perform the multi-stage conical drawing process. Not only does it have the disadvantage of not being able to adjust the mounting position, but when plastic processing is applied to form radial protrusions on the rim, deformation strain occurs in the rim, resulting in the formation of radial protrusions around the circumference. This had the fatal drawback of causing a discrepancy in the precision of the teeth.

The present invention prevents the reduction in the strength of holding the shaft end due to the forming of the boss part of the sheet metal pulley, and also allows the attachment position of the sheet metal pulley to the shaft end to be adjusted in the axial direction, and also improves the accuracy of the circumferential teeth. This is a shaft mounting device for a sheet metal pulley that can be formed integrally with the pulley without deterioration.The following describes an embodiment of the present invention based on the drawings.As shown in FIG. The peripheral surface part 1 has a large number of teeth 2 formed on its outer peripheral surface, and the boss part 3 to which the shaft end S of the pulley rotating shaft is attached is continuous with the peripheral surface part 1 by the rim part 4. The boss portion 3 and the rim portion 4 are integrally formed from a single sheet metal.

The boss portion 3 is formed by punching into an annular shape a plurality of chevron-shaped protrusions 5, 5, . The chevron-shaped protrusions 5, 5... spread in the circumferential direction of the shaft end S, and both chevron-shaped leg ends are continuous with the boss portion 3 in the circumferential direction as shown in FIG. It forms a fitting and holding surface for the outer peripheral surface of the end portion.
Furthermore, if the punched end surface into which the outer periphery of the shaft end of the chevron-shaped protrusions 5, 5... is fitted is made into an arc shape that fits the shaft end outer peripheral surface, the shaft end is tightly fitted into the chevron-shaped projections 5, 5... and accurate radial positioning. code 6
are the punched holes of the chevron-shaped protrusions 5, 5..., and the boss portion 3
In the center of is an insertion hole 8 for a fastening bolt 7 that integrally fastens the end surface of the shaft end S and the pulley P, and at a position eccentric to the hole 8 is a hole 8 for the relative rotation of the pulley P and the shaft end S. A lock pin hole 9 is provided to prevent rotation. Note that the rotation preventing means is not limited to the dowel pin, but may be formed with a concavo-convex portion that fits mutually on the shaft end surface or the shaft end circumferential surface and the pulley boss portion.

As described above, the present invention involves punching out a plurality of chevron-shaped protrusions 5, 5, . Since it is formed by an end surface, the boss portion 3 other than the chevron-shaped protrusion is not thinned at all, and furthermore, none of the leg ends of the chevron-shaped protrusion are free ends, and the boss portion 3 is not thinned in the circumferential direction. Part 3
Since it is continuous to
... can reliably position and hold the shaft end S at an accurate center position, and furthermore, punching and forming the chevron-shaped protrusions 5, 5 ... on the boss portion 3 is an extremely easy process. A plurality of chevron-shaped protrusions 5 that fit and hold the shaft end S,
5 are arranged annularly in the circumferential direction and are not arranged radially in the radial direction, so no deformation strain occurs in the rim part 4, so the accuracy of the teeth formed on the outer periphery is not reduced, and the rim Since it is possible to perform a multi-stage annular conical drawing process on the part 4, the shaft mounting position regulating surface that the shaft end surface comes into contact with can be formed at a desired position in the axial direction, so that the shaft of the sheet metal pulley can be It has many excellent effects, such as being able to select the end attachment position as desired.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; FIG. 1 is a front sectional view of a pulley, FIG. 2 is a side view of FIG. 1, and FIG. 3 is an enlarged sectional view of a chevron-shaped protrusion. 1...Surrounding part, 3...Boss part, 4...Rim part,
5... Chevron-shaped protrusion, 8... Fastening bolt insertion hole, 9...
... Rotating lock pin insertion hole.

Claims (1)

[Scope of utility model registration request] In a sheet metal pulley whose peripheral surface, rim, and shaft end mounting boss are integrally molded from a single plate, the shaft end mounting boss has a plurality of chevron-shaped protrusions that are punched out in an annular shape in the circumferential direction. Both chevron-shaped leg ends are connected to the boss portion in the circumferential direction, and the punched end surfaces thereof are protruded as fitting and holding surfaces for the outer peripheral surface of the shaft end, and a fastening bolt insertion hole for fixing the shaft end is provided at the center position of the boss portion. Also, a shaft mounting device including a means for preventing rotation of the shaft end and the pulley in the boss portion.