JPH0579417B2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a method for manufacturing a V-pulley.

(Prior art) Traditionally, V-pulleys have been manufactured by casting, die casting, or press forming.Casting and die casting are finished by cutting, and press forming involves press forming two discs. , a manufacturing method in which a V-groove is formed by welding the two pieces together, or JP-A-48-
No. 34071 proposes a method of manufacturing a V-pulley by pushing an inner roll in the axial direction while rotating a pressed plate-shaped material or pipe material with an upright peripheral edge.

(Problems to be Solved by the Invention) In the conventional V-pulley described above, first of all, in the case of casting, a wooden mold is required, uneven thickness occurs during casting, poor dynamic balance, and the plate is placed in a foundry. Due to the extremely poor working environment, there has been a severe turnover of employees in recent years, resulting in a chronic labor shortage, which has led to a decline in productivity and a rise in the price of cast metal products, thus eliminating the merits of using cast metal pulleys. It is in. Next, in the case of aluminum die casting, although it is advantageous for mass production, it requires expensive molds, and the resulting product is softer than iron, so it is difficult to use it in drive systems with large transmissions.
It is subject to severe wear and is prone to slipping, making it particularly unsuitable for use in automobiles, agricultural machinery, etc. Therefore, these casting and aluminum die casting methods cannot be used as they are, and require mechanical finishing, which increases labor and cost. In addition, the press forming method generates distortion due to heat because welding is performed later, requires machining and rehoming to remove runout, and requires molds for different sizes of V-pulleys.

In addition, in the manufacturing method of JP-A-48-34071,
This is a V-pulley manufacturing method that is intended for use with press-formed dish-shaped materials or pipe materials with upright edges, and when processing such materials, small rotations of the normal contact surfaces are required. Rolls reduce the thickness of the material and cause it to be cut, so it is necessary to use a special inner roll that is close to the outside diameter of the material to increase the forming contact surface.Moreover, as processing progresses, the center of the V-groove moves. For this purpose, it is necessary to move the roll in the direction of the rotational axis, which requires time and effort to set the amount of movement corresponding to the type of V-groove, and the use of inner rolls that have a complicated shape and are difficult to support in rotation, even for manufacturing equipment. This method has the disadvantage that it is an extremely complicated and expensive device due to the provision of a pressing die, means for moving the rolls, and the like.

The present invention aims to solve the above-mentioned problems, namely, to provide a method for manufacturing a V-pulley that is extremely easy to process, has good dynamic balance, and is inexpensive, eliminating the need for expensive manufacturing equipment or subsequent machining. The purpose is to provide

(Means for Solving the Problems) To explain the means for solving the above problems using figures corresponding to embodiments, the present invention provides at least the following: A pair of donut-shaped hollow disks 2, 2' are welded concentrically to the shaft 1. Next, while rotating around the shaft 1, a rotary roll 3 having an inverted V-shaped outer circumference and an abutment groove 3a formed at the base of the inverted V is placed between the discs 2 and 2'. Push in from the outer diameter direction toward the axial direction until the abutment groove 3a is pressed against the outer periphery 2b, 2'b of the disc 2, 2', and form the V groove A and the outer periphery in the disc 2, 2'. This is a manufacturing method in which curling and chamfering of 2b and 2'b are simultaneously formed.

(Function) A pair of discs 2 and 2' concentrically welded to the outer periphery of the shaft 1 are rotated around the shaft 1, and between the discs 2 and 2', the roll holder 5 is rotated. When the rotary roll 3, which is freely attached and has an inverted V-shape on its outer periphery, is pushed in from the outer radial direction toward the axial center, the rotary roll 3 is also rotated by the discs 2 and 2'. The disks 2, 2' are pushed open left and right along the inverted V-shaped surface and plastically deformed to form a V-groove A. As the rotating roll 3 is pushed further, the abutment groove 3a of the rotating roll 3 eventually comes into contact with the outer circumferences 2b, 2'b of the disks 2, 2'. If the pressing amount is increased, the outer peripheries 2b, 2'b will be curled, and if the amount is decreased, the outer peripheries will be chamfered, which can be selected as required. In addition, since the rotary roll 3 rotates when pressing, even if the disks 2, 2' are strongly pressed, there is no local wear and the wear is dispersed over a wide range of the entire circumference, which greatly reduces the degree of wear and facilitates processing. Inside, the discs 2, 2' are simply pushed open left and right, so there is no risk that the discs 2, 2' will be squeezed, thinned, and torn.

(Example) Examples of the present invention will be described below with reference to the drawings. First, a cylindrical or round rod shaft 1 and two donut-shaped disks 2 and 2' are prepared. These two disks 2,
2' usually has the same thickness, outer diameter, and inner diameter of the central holes 2a and 2'a, as shown in FIG. It is slightly larger than the outer diameter. Then, the shaft body 1 is inserted into the holes 2a, 2'a of the discs 2, 2', and the discs 2, 2' are fitted concentrically around the outer periphery of the shaft body 1 with an appropriate distance between them.
They are fixed by welding, but as shown in Fig. 3, the inner diameter of the hole 2'a in one disk 2' is the same as that of the hole 2a in the other disk 2.
The discs 2 and 2' are bored appropriately larger than the inner diameter of the disc and formed into a substantially dish shape, and when welding, both discs 2 and 2' are simultaneously welded to the shaft body 1 with the holes 2a and 2'a sides in contact with each other. Alternatively, the disk 2 may be welded to the shaft 1 and the disk 2' may be welded to the disk 2 (see FIG. 3b).

After welding the disks 2, 2' to the shaft 1, they are rotated using a lathe or a special machine with the shaft 1 as the center. Next, as shown in Fig. 4, the rotary roll 3, which is rotatably attached to the roll holder 5 and whose outer circumferential side is sharpened in an inverted V shape, is pushed between the disks 2 and 2' from the outer radial direction toward the axial center. As the disks 2 and 2' move, the V of the rotating roll 3
The V-groove A is formed by being pushed open at an angle and plastically deformed. In this case, the discs 2 and 2' are made of steel plates, especially finished steel plates, but when forming the V groove A, the V angle of the rotating roll 3 is greater than the V angle of the V belt 4 to which it is applied. It is also set with a large spring back in mind. Further, an abutting groove 3a is formed at the inverted V-shaped base of the rotating roll 3,
The outer periphery 2b of the disks 2, 2' up to the abutting groove 3a,
By pressing 2′b, the outer peripheries 2b and 2′b are also curled outward at the same time as the V-groove A is formed.
Alternatively, the edges of the corners may be rounded off. Note that the above V-pulley is for one, but in the case of two or more, a pair of discs 2, 2'
It is sufficient to provide two or more pairs of these on the shaft body 1 and process them in the same manner as described above.

(Effect of the invention) The present invention has the following effects.

Compared to aluminum die casting and press forming, fewer molds are required, and a simple and inexpensive mold for punching or drawing the discs 2, 2' is sufficient.
It does not require any modification or finishing of the groove A, and therefore can be manufactured at low cost.

Conventional press working methods using dish-shaped materials or pipe materials with upright edges require the use of special inner rolls to prevent the materials from tearing during processing, and the use of special inner rolls to prevent the materials from tearing during processing. It required complicated movement to simultaneously push in the diameter direction and move parallel to the center of rotation, which required adjustment of the amount of movement depending on the type of V-groove A, making processing difficult and the equipment complicated. However, in the present invention, by using a pair of discs 2, 2' as the raw materials, the rotating roll 3
The V groove A is formed by simply pushing the V groove A between the discs 2 and 2' at right angles toward the center of rotation.
Regardless of the type of groove A, the center of the V-groove A can be accurately machined, and the center of the V-groove A can be accurately machined.
2' will not be torn by the rotating roll 3, so no complicated processing equipment is required.

For the discs 2, 2', finished steel plates with uniform plate thickness can be used, and the V-groove A is processed after welding. Because it is formed by being pressed in, there is no eccentricity of the V-groove A even if there is thermal distortion due to welding, and the dynamic balance when rotating is extremely good, with almost no runout.

Since the rotating roll 3 is provided with the abutting groove 3a, it is possible to form the V-groove A on the discs 2 and 2' and simultaneously perform curling and chamfering on the outer circumferences 2b and 2'b.
To improve the appearance finish and to make belt hanging safe and easy.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a V-pulley showing the first embodiment of the present invention, Fig. 2 is a perspective view of a disc, Fig. 3 is a diagram showing how the disc is attached during welding, and Fig. 4 is a diagram of a V-groove. It is an explanatory view showing a processing method. 1... Shaft body, 2, 2'... Disk, 2b, 2'b...
...Outer periphery, A...V groove, 3...Rotating roll, 3a...
...Abutting groove.

Claims (1)

[Claims] 1 At least two pairs of donut-shaped disks 2, 2' are welded to the outer periphery of the shaft 1, which is a cylinder or a round bar, concentrically with the shaft 1, and then the While rotating the discs 2, 2', a rotary roll 3 having an inverted V-shape on the outer periphery and an abutment groove 3a formed at the base of the inverted V is placed between the discs 2, 2'. Push from the radial direction toward the axial direction until the abutment groove 3a is pressed against the outer periphery 2b, 2'b of the discs 2, 2', and form the V groove A and the outer periphery 2b in the discs 2, 2'. , 2'b, a method for manufacturing a V-pulley in which curling and chamfering are simultaneously formed.