JPH0255133B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to a method for manufacturing lightweight microshafts, and in particular, to manufacturing lightweight microshafts that are optimal for use in fixed shafts and rotating shafts of various devices such as tape recorders and video cameras. Regarding the manufacturing method for forming.

(Prior Art) In recent years, devices such as tape recorders and video cameras are required to be easily portable, and accordingly, devices are becoming more compact and lightweight.

On the other hand, conventionally, various shafts used in the above-mentioned devices are made by cutting a raw material coil made of wire into a straight shape as a shaft material, then cutting the shaft material to a specified size or cutting it to a specified size, and then cutting it several times. It was manufactured through various processing steps, grinding and super finishing of each part.

(Problems to be Solved by the Invention) However, since these conventional microshafts have solid round rod shafts, the influence of the weight of these shafts on the equipment has been a major problem.

Therefore, in view of the above-mentioned problems, the present invention makes the microshafts of various home appliances, audio equipment, etc. hollow shafts, that is, cylindrical.
It was created with the aim of providing a lightweight microshaft that can reduce the weight of various devices, facilitate the manufacture of the shaft itself, and reduce costs.

(Means for Solving the Problems) In the manufacturing method of the microshaft, the present invention first sequentially draws a metal plate material using a punch and die to form a cylinder with a small diameter and deep bottom, and then , an intermediate sizing process is performed using a trimming punch and a die, and then drawing process is performed sequentially using a punch and a die again to form a cylindrical body with a small diameter and a deep bottom. By performing final sizing processing, or by further drilling a hole at the bottom after this final sizing processing to form an elongated bottomed cylinder shape or a bottomless cylindrical shape, or by forming a lightweight micro In the shaft, by performing a mouth drawing process on the opening end of the microshaft in the shape of an elongated bottomed cylinder or a bottomless cylinder, or by By providing a stepped portion and forming the diameter smaller than the overall diameter, or by forming a flange at the open end of an elongated bottomed cylindrical or bottomed cylindrical microshaft, or by forming a slender bottomed cylindrical shape. The above-mentioned problem is solved by forming a stepped portion in a microshaft having a cylindrical shape or a bottomless cylindrical shape, so that the diameter of the bottom portion is smaller than the diameter of the open end portion.

(Function) The method for manufacturing a lightweight microshaft according to the present invention involves first sequentially drawing a metal member using a punch and a die to form a cylinder with a small diameter and deep bottom, and then drawing the metal member using a trimming punch and a die. Perform intermediate sizing processing. Thereby, an elongated cylindrical shape with a bottom is formed as a reference.

After that, it is sequentially drawn again using a punch and die to form a cylinder with a small diameter and deep bottom.
After that, final sizing processing is performed using a trimming punch and die. As a result, a hollow ultra-thin shaft that can be used as a microshaft for various home appliances, audio equipment, etc. is finished to a desired standard size.

Further, after this final sizing process, a hole is further drilled at the bottom to form a bottomed cylindrical shape, into which a suitable shaft can be inserted.

On the other hand, in the lightweight microshaft formed in this way, the opening end of the elongated bottomed cylindrical or bottomed cylindrical microshaft is subjected to a drawing process, or the elongated bottomed cylindrical or bottomed cylindrical microshaft is A stepped portion is provided near the opening end of the shaft to form a diameter smaller than the overall diameter, or a flange is formed at the opening end of a microshaft in the shape of an elongated cylinder with a bottom or a cylinder with an open bottom. In a bottomed cylindrical or bottomless cylindrical microshaft, a stepped portion is formed so that the bottom diameter is smaller than the open end diameter to correspond to the mounting manner of the microshaft.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. In the figure, reference numeral 1 denotes a microshaft main body, which is formed as an elongated cylindrical body with a bottom by re-drawing a plate material such as a stainless steel plate.

That is, first, punches P1 and P are punched on the metal member.
2... and dies D1, D2... are used to sequentially perform deep drawing from a shape with a large diameter and a shallow bottom to a shape with a small diameter and a deep bottom. As shown in FIG. 15, it is formed by sequentially performing deep drawing using a transfer press machine having a processing stage 14 and continuous transfer processing dies A.

In the first processing stage, the blanking punch P
1A and No. 1 drawing punch P1B integrally formed, a punch P1, a blanking die D1A and No. 1
A blank B is formed from a strip-shaped plate material using a first processing die A1 configured with a drawing die D1B integrally formed with the die D1, and this blank B is subjected to a shallow drawing process with a large diameter.

In the second to fourth processing stages, No. 2 to No. 4 drawing punches P2, - P4 and No.
Using the second to fourth processing dies A2, to A4, which are composed of two to four drawing dies D2, to D4, drawing is performed sequentially from the blank B with a large diameter and shallow bottom to the blank B with a small diameter and deep bottom.

In the fifth processing stage, intermediate sizing processing is performed using a fifth processing die A5 composed of a No. 5 trimming punch P5, a No. 5 trimming die D5, a No. 5 knockout N5, and a No. 5 liner L5.

In the 6th to 9th processing stages, No. 6 to 9 drawing punches P6, to P9 and No. 6 to 9 drawing dies D6, to
D9 and the sixth to ninth processing molds A6, ~A
9, similarly to the second to fourth processing stages, the drawing process is performed sequentially from the large-diameter, shallow-bottomed blank B to the small-diameter, deep-bottomed blank B.

In the 10th processing stage, similarly to the 5th processing stage, the 10th processing die A1 is made up of a No. 10 trimming punch P10 and a No. 10 trimming die D10.
Perform final sizing processing using 0.

In the 11th processing stage, No. 11 hole punch P11 and No. 11 hole die D
The holes are made using the eleventh processing die A11, which is made up of 11 and 11.

In the 12th and 13th stages, No. 12 and No. 13 opening punches P12, P13 and No. 12 and No. 13 knockouts N1 are formed in a conical shape along the punch center line.
2, N13 and No.12 and No.13 liners L12, L1
12th and 13th processing molds A12 and A1 consisting of 3 and 3.
Step 3 is performed to draw the edge of the blank B in sequence.

In the 14th processing stage, no processing is performed and the product is discharged.

The transfer processing die A in the illustrated example can be modified as appropriate depending on the desired shape of the microshaft main body 1, and may be a stepped processing die, or may be used to alleviate the deformation of the blank B, balance the press load, etc. An idle stage (both not shown) or the like can be added to achieve this. Moreover, the symbol G2 shown in the figure,
~G13 holds blank B and dies D2, ~D1
This is a guide that will take you to step 3.

The open end 2 of the microshaft main body 1 formed in this way can be bent inward to have an arcuate cross section as shown in FIG. 2 and narrowed inward, as shown in FIG. The outer diameter of the shaft body 1 may be made thinner than the outer diameter of the shaft body 1 through the stepped portion 3, or a flange 4 may be formed as shown in FIG. By restricting the opening end 2 in this manner, it becomes easy to press-fit and attach the microshaft main body 1 to the substrate 5, etc., and also to ensure that the microshaft body 1 is securely attached to the substrate 5. Become. The bottom 6 of the microshaft main body 1 may have a spherical bottom as well as a flat bottom.
It may also be formed into a narrow stepped shaft shape. Incidentally, the peripheral surface of the shaft body 1 is ground and subjected to surface treatments such as heat treatment and plating, if necessary.

The microshaft body 1 constructed in this way is attached to the substrate 5 etc. by press-fitting it into the attachment hole 8 of the substrate 5 with the narrowed open end 2 as the tip, as shown in FIG. Further, as shown in FIG.
The stepped portion 3 is press-fitted into the mounting hole 8 of the mounting hole 8 so as to be in contact with the edge of the mounting hole 8, and then the opening end portion 2 is caulked so as to expand outward to securely fix it to the board 5. Also good. Furthermore, as shown in FIG. 8, the microshaft main body 1 having an open end 2 with a flange 4 is inserted from the back side of the board 5 toward the front side, and the flange 4 is inserted into the back side edge of the mounting hole 8 of the board 5. The microshaft body 1 may be fixed so that it does not fall off the substrate 5 by pressing the flange 4 with a presser plate 9 or the like. Furthermore, FIG.
It is press-fitted into the tape guide shaft and is configured to be used as a tape guide shaft.

Further, as shown in FIG.
etc., and a rotating body 1 made of plastic etc.
1 may be rotatably inserted and press-fitted into the substrate 5 with the bottom 6 of the microshaft body 1 as the tip. With such a configuration, it is possible to arrange the rotating body 11 in the microshaft body 1 and to attach the microshaft body 1 to the substrate 5. can be attached to the substrate 5 at the same time, facilitating assembly and simplifying the configuration. That is, in the past, the E
A ring mounting mechanism was formed on the shaft circumferential surface and an E-ring or the like was fitted into this mounting groove to prevent the rotating body from falling off, but with the above structure, the E-ring mounting groove can be eliminated. Furthermore, the E-ring and the like are not required, and furthermore, the E-ring mounting process can be omitted, so the structure is simple and assembly is easy. The microshaft body 1 having the hole 12 in the bottom part 6 can be attached to the substrate 5 by inserting the opening arrow 13 into the microshaft body 1 as shown in FIG. 6 is expanded and deformed within the mounting hole 8 and then fitted into the mounting groove 14 within the mounting hole 8. By adopting such a method for attaching and fixing the microshaft, the process of attaching the microshaft can be easily automated.

(Effects of the Invention) The present invention is constructed as described above, and in the method for manufacturing a microshaft, first, punches P1 to P4 and dies D1 to D4 are applied to a metal plate to form a cylinder with a small diameter and a deep bottom. Sequential drawing processing is performed, then intermediate sizing processing is performed using trimming punch P5 and die D5, and then punches P6 to P6 are used again.
9 and dies D6 to D9 to form a bottomed cylindrical body with a small diameter and deep bottom, and then final sizing processing is performed using a trimming punch P10 and die D10, or this final After the sizing process, a hole is further drilled at the bottom to form an elongated cylinder with a bottom or a cylinder with an open bottom.By cutting the wire rod in a straight line and cutting it several times, the end face, circumferential surface, etc. This eliminates the need for grinding, which simplifies the machining process.Also, because the process is done by deep drawing several times from the plate material, the shaft body is not solid but cylindrical, that is, hollow, unlike conventional ones. In comparison, the weight can be significantly reduced by 1/4 to 1/5. Therefore, it is possible to provide a microshaft suitable for use in tape recorders, video cameras, etc., which especially require portability. Furthermore, reducing the amount of material also reduces manufacturing costs, making it possible to provide the product at a low price. Furthermore, by using a dedicated transfer press machine that is easy to automate, mass production is possible and can be easily manufactured, making it possible to provide an even more inexpensive microshaft.

Moreover, many of the microshafts suitable for use in tape recorders, videos, etc. have very small diameters and are long, so if the forming is completed by continuous deep drawing, As variations occur and the end face of the microshaft approaches the final stage, cracks often occur on the end face of the microshaft due to differences in elongation, or the microshaft becomes bent due to residual stress. However, in the case of this invention, an excellent microshaft with good accuracy can be obtained because deep drawing is performed after intermediate sizing processing, and then final sizing processing is performed. This is the most suitable processing method since many of these types of microshafts require very strict dimensional accuracy.

In addition, since the material is formed into a cylindrical body by re-drawing, the material is work-hardened through several deep drawing processes, increasing its strength and hardness as a microshaft, which significantly reduces weight while increasing strength. A microshaft that is highly wear resistant can be obtained.

Furthermore, since it is formed as a cylinder with a bottom or a cylinder with a hole 12 in the bottom 6, the strength of the cylinder itself, that is, the microshaft main body 1, can be further improved by the bottom 6. That is,
Even if the microshaft main body 1 is made hollow in order to reduce weight, the strength of the microshaft main body 1 can be maintained by this bottom part 6. This prevents the shape from changing and makes it resistant to press-fitting. Moreover, this bottom portion 6 can also play a major role in maintaining dimensional accuracy and roundness of the outer diameter.

On the other hand, the opening end of the elongated bottomed cylindrical or bottomed cylindrical microshaft is subjected to a drawing process, or
Alternatively, the vicinity of the open end of the elongated bottomed cylindrical or bottomed cylindrical microshaft may be provided with a step so as to have a diameter smaller than the overall diameter; A flange is formed at the open end of the microshaft, or a step is formed in an elongated bottomed cylindrical or bottomed cylindrical microshaft so that the diameter of the bottom is smaller than the diameter of the open end. By doing so, it is possible to accommodate various mounting modes.

The shape of the bottom 6 is, for example, a flat bottom when used as a fixed shaft, and a spherical bottom when used as a rotating shaft, as shown in FIGS. 11 and 12. This spherical bottom not only has the characteristics of a flat bottom, but also has the ability to reduce frictional resistance when the shaft end is used as a thrust receiver.

In addition, if a non-magnetic product is required for video equipment or tape recorders that use magnetic tape, it should be formed from a stainless steel plate made of a material that is not particularly magnetized, and drawn several times. Prevent magnetism from occurring even during processing.

As explained above, according to the present invention, it is possible to significantly reduce the weight of the microshaft, provide sufficient strength, and provide a highly accurate microshaft.
Furthermore, the number of manufacturing steps can be reduced, mass production is possible, and the product can be provided at a low price, resulting in various excellent effects.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention, and FIGS. 1 to 5 are overall vertical cross-sectional views of each embodiment, and FIGS. 6 to 10 are main parts showing the state in which they are attached to a board as a fixed shaft. Fig. 11 is a partially omitted vertical cross-sectional view showing how the motor is installed as a rotating shaft, and Fig. 12 is a partially omitted longitudinal cross-sectional view showing how the rotating shaft is used in the tape feed mechanism of a tape recorder. A top view, Figure 13A is a cross-sectional view of the main part with a bottomless cylindrical shape, Figure 13B is a cross-sectional view of the main part showing the mounting and fixing method,
FIG. 14 shows the blank shape obtained at each stage of the transfer processing die, and is a plan view and a longitudinal sectional view, and FIG. 15 is a longitudinal sectional view of the transfer processing die. DESCRIPTION OF SYMBOLS 1... Microshaft main body, 2... Opening end, 3... Step part, 4... Tsuba, 5... Substrate, 6...
Bottom part, 7...Step part, 8...Mounting hole, 9...Press plate, 10...Flat washer, 11...Rotating body, 12...
Hole, 13...Open arrow, 14...Mounting groove, 15...
Tape, 16... Guide arm, A... Transfer processing mold, B... Blank, P1,~P12...
...Punch, D1, ~D11...Die, A1, ~A
13...type, G2, ~G4, G6, ~G9, G1
1, ~G13...Guide, N5, N12, N13
... Knockout, L1, ~L14 ... Liner.

Claims (1)

[Claims] 1. In the method for manufacturing a microshaft, first, a metal plate is sequentially drawn using a punch and a die to form a cylinder with a small diameter and a deep bottom, and then a trimming punch and a die are used to draw the metal plate material. After that, the material is subjected to intermediate sizing processing using a punch and a die, and then drawing processing is performed sequentially using a punch and die to form a cylindrical body with a small diameter and deep bottom.Furthermore, the final sizing processing is performed using a trimming punch and a die. Alternatively, after this final sizing process, a hole is further drilled at the bottom to form an elongated cylindrical shape with a bottom or a cylindrical shape with an open bottom. 2.Claim 1, in which the opening end of the elongated bottomed cylindrical or bottomed cylindrical microshaft is subjected to a drawing process.
The method for manufacturing the lightweight microshaft described. 3. The method for manufacturing a lightweight microshaft according to claim 1 or 2, wherein the microshaft, which has a slender bottomed cylindrical shape or a bottomed cylindrical shape, is provided with a stepped portion in the vicinity of the open end thereof to have a diameter smaller than the overall diameter. 4. The method for manufacturing a lightweight microshaft according to claim 1, wherein a flange is formed at the open end of the elongated bottomed cylindrical or bottomed cylindrical microshaft. 5. The lightweight microshaft according to any one of claims 1 to 4, wherein the elongated bottomed cylindrical or bottomed cylindrical microshaft is formed with a step so that the diameter of the bottom is smaller than the diameter of the open end. manufacturing method.