JPH08197179A - Production of intermediate material for producing metallic bellows and apparatus for production therefor - Google Patents

Abstract

PURPOSE: To efficiently and accurately execute an operation to produce an intermediate material by forming annular recessed parts on the outer peripheral surface of a pipe stock. CONSTITUTION: The pipe stock 1 is inserted into die elements 58, 58 circumferentially divided to >=3 pieces and thereafter the respective die elements 58, 58 are displaced to the inner side in a diametral direction. The front ends of projecting lines 54, 54 formed on the inner peripheral side faces of the respective die elements 58, 58 are butted against the outer peripheral surface of the pipe stock 1 and the annular recessed parts 7, 7 are formed in the butt parts, by which the intermediate material 8 is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for manufacturing a metal bellows incorporated in a steering device of an automobile, for example.

[0002]

2. Description of the Related Art Bellows having a corrugated cross-sectional shape in the axial direction by alternately connecting a large-diameter portion and a small-diameter portion have been conventionally used as a component of various mechanical devices. Among such bellows, those made of metal have a certain degree of bending rigidity, and when a large impact is applied in the axial direction, they are plastically deformed while absorbing the energy of this impact. , Its total length is shortened. Focusing on the characteristics of such metal bellows, research has been conducted on configuring a shock absorbing steering device by using a metal bellows as a steering column of an automobile.

The bellows constituting the shock absorbing steering device is required to have a large rigidity as compared with a metal bellows which is merely required to be flexible, such as used for piping. Conventionally, such a highly rigid metal bellows is
It was manufactured by the method shown in FIG. 5 or FIG.

First, the method of the first example shown in FIG. 5 is No. 9 of "Pipe processing method" by Masanobu Nakamura, published by Nikkan Kogyo Shimbun.
It is described on page 6. In the method of this first example,
A high-pressure liquid is fed into the circular tube 1 made of metal, and a bulge process is performed to bulge a part of the tube 1 outward in the diametrical direction by hydraulic pressure to obtain a metal bellows 2. The lower half of FIG. 5 shows the state of the raw tube 1 before molding,
The upper half shows the metal bellows 2 after molding, respectively.

At the time of molding, a liquid such as water or oil is fed at a high pressure into the inside of the base pipe 1 set in the forming cylinder 3, and a force in the expansion direction is applied to the inner peripheral surface of the base pipe 1. At the same time, the molding pistons 4a and 4b fitted to both ends of the molding cylinder 3 are strongly pressed in the directions toward each other by the pressure of the liquid. It should be noted that annular holding rings 5 and 5 are fitted at positions spaced apart from each other in the axial direction (the horizontal direction in FIG. 5) in the molding cylinder 3 so as to be displaceable in the axial direction. In this way, when hydraulic pressure is applied to each part, the whole length of the raw pipe 1 as shown in the lower half part of FIG. It becomes the metal bellows 2 as shown in the section.

Next, the method of the second example shown in FIG. 6 is described in Japanese Patent Laid-Open No. 63-157724.
In the method of the second example, a part of the raw material tube 1 in the axial direction (vertical direction in FIG. 6) is Joule-heated by the high-frequency induction coil 6, and the raw material tube 1 is pressed in the axial direction. As a result, the portion whose temperature has risen due to Joule heat is plastically deformed so as to expand outward in the diametrical direction. This work is performed a plurality of times by slightly shifting the high frequency induction coil 6 in the axial direction, and the large-diameter portion (bulging portion) and the small-diameter portion are alternately continuous to form a wavy cross-sectional shape in the axial direction. Obtain a metal bellows.

However, in the case of the conventional method as described above, there are points to be solved, such as the following (1) and (2). (1) First, in the case of the method of the first example shown in FIG. 5, not only the equipment cost is increased, but also it is possible to obtain a metal bellows having a great rigidity so that an impact absorption type steering device can be configured. difficult. That is, since the metal base pipe 1 is plastically deformed by the hydraulic pressure, it is necessary to generate a considerably large hydraulic pressure, and an expensive hydraulic pressure generator is required. Further, the raw pipe 1 for making the metal bellows having a large rigidity as described above.
In that case, the plate thickness increases correspondingly, and a large force is required to cause plastic deformation, which makes molding by hydraulic pressure difficult. Further, since the liquid is used, workability is poor and automation is difficult. Therefore, the manufacturing cost of the metal bellows becomes high.

(2) Next, in the method of the second example shown in FIG. 6, an expensive high-frequency induction coil 6 is required, which not only increases the equipment cost but also processes a plurality of bulging portions one by one. Therefore, processing efficiency is poor. Therefore, the manufacturing cost of the metal bellows also becomes high. Moreover, since the base pipe 1 is plastically deformed in a heated state, it is difficult to secure dimensional accuracy and shape accuracy of the plastically deformed portion, and the accuracy of the obtained metal bellows is not necessarily good.

[0009]

DESCRIPTION OF THE PRESENT INVENTION In view of such circumstances, the present inventor has previously made a metal having high rigidity and high precision which can be incorporated into a steering device or the like by using a relatively simple and inexpensive equipment. Invented a method for producing a metal bellows capable of producing a bellows (Japanese Patent Application No. 5-296406). When carrying out the method for manufacturing a metal bellows according to the preceding invention, first, as shown in FIG. 7 (A), a metal plate which is plastically deformable, such as a steel plate or a stainless steel plate, is formed into a cylindrical shape. Prepare the raw tube 1. The length L ₁ of the raw tube 1 is sufficiently larger than the length L ₃ of the metal bellows 2 which is the finished product shown in FIG. 7C (L ₁ >> L ₃ ). The outer diameter D ₁ of the raw tube 1 is sufficiently smaller than the outer diameter D ₃ of the metal bellows 2 (D ₁ << D ₃ ). Further, the inner diameter d _{1 of the} raw tube ₁
Is slightly larger than the inner diameter d ₃ of the metal bellows 2 (d ₁ > d ₃ ). The plate thickness hardly changes before and after processing.

Then, in the first step, as shown in FIG. 7 (B), a plurality of annular recessed portions 7, 7 are formed on the outer peripheral surface of the element pipe 1 so as to cover the entire circumference of the element pipe 1. The intermediate member 8 is formed intermittently in the axial direction of the pipe 1 (left-right direction in FIG. 7).
And The length L ₂ of the intermediate member 8 is equal to or slightly shorter than the length L _{1 of the} raw tube 1 (L ₁ ≧ L ₂ ). The outer diameter D ₂ of the intermediate member 8 is the same as the outer diameter D _{1 of the} raw tube 1 (D
₁ = D ₂ ). Further, the inner diameter d ₂ of the intermediate member 8 is
It is smaller than the inner diameter d _{1 of the} raw tube 1 (d ₁ > d ₂ ). The above-described intermediate material 8 is further processed in the second step to obtain the metal bellows 2 as shown in FIG. 7 (C).

In the first step, a plurality of annular recesses 7, 7 are formed on the outer peripheral surface of the raw tube 1 to form an intermediate member 8. In the embodiment of the prior invention, as shown in FIGS. This is performed by three sets of rotating rollers 9, 9. Each of these rotating rollers 9,
9 is arranged around the base pipe 1 in parallel with the base pipe 1 and is pressed toward the outer peripheral surface of the base pipe 1 while rotating in the same direction (clockwise in the example shown in the drawing). . On the outer peripheral surface of each rotating roller 9, 9, there are formed a plurality of annular projections 10, 10 each extending in the circumferential direction, and annular recesses 7, 7 to be formed.
The pitch is set to match the pitch of. In addition, the axial direction of the annular projections 10 and 10 on the outer peripheral surfaces of the rotating rollers 9 and 9 (see FIG.
The left and right directions, and the front and back directions in FIG. 9) are in phase with each other.

By rotating the rotary rollers 9 and 9 in the same direction and pressing the annular projections 10 and 10 formed on the outer peripheral surfaces of the rotary rollers 9 and 9 against the outer peripheral surface of the raw tube 1, The outer peripheral surface of the raw tube 1 is plastically deformed. As a result, the annular recesses 7, 7 are formed according to the pitch of the annular projections 10, 10 to form the intermediate member 8.

The intermediate material 8 thus manufactured is subjected to the second step of processing to obtain the metal bellows 2 as shown in FIG. 7C, and the manufacturing apparatus as shown in FIG. Attach to. This manufacturing apparatus includes a cored bar 11, a plurality of retaining rings 12, 12 each having an annular shape, and a pair of pressing rings 13, 13 also formed in an annular shape.

The respective members 11, 12 and 13 are set in a holding cylinder (not shown) formed in a cylinder shape, for example. That is, each of the retaining rings 12 and 12 and the pressing ring 1
3 and 13 are inserted into the holding cylinder. Then, the remaining members 12, 12 and 13 excluding one (for example, the right side of FIG. 10) pressing ring 13 are axially (FIG.
(Left and right direction) can be freely displaced. When the second step is performed, the remaining members 12, 12, 13 are pressed toward the one pressing ring 13 by a ram or the like of a pressing device. During the pressing operation, the core metal 11 is
It exists inside all the retaining rings 12, 12 and the pressing rings 13, 13. Since a vertical press device may be used in some cases, the vertical and horizontal directions in the drawing do not necessarily match the actual vertical and horizontal directions.

The core metal 11 of each of the members 11, 12 and 13 is cylindrical and has a length sufficiently larger than the length L _{2 of the} intermediate member 8 and the inner diameter d _{2 of the} intermediate member 8. And has substantially the same outer diameter. Further, tapered end portions 14 and 14 are provided at both axial ends of the cored bar 11 to facilitate the work of inserting the cored bar 8 into the intermediate member 8.

As shown in FIG. 11, each retaining ring 12, 12 is formed by combining a plurality (4 in the illustrated example) of ring elements 15, 15. Inner peripheral edge portions of the respective ring elements 15, 15 each formed in an arc shape are tapered in a wedge shape. In addition, the cross section of the inner peripheral edge of each of the rings 15, 15 is formed in an arc shape. The radius of curvature of the inner peripheral edge in the cross-sectional direction is such that the annular concave grooves 16 and 16 sandwiched between the large diameter portions 22 and 22 adjacent to each other on the outer peripheral surface of the metal bellows 2 to be manufactured.
The radius of curvature in the cross-sectional direction of the bottom portion of FIG. 7C is matched. Further, the plurality of ring elements 15, 15 are combined to form the holding rings 12, 12, and each of the holding rings 12, 12 is set in the holding cylinder, and each of the ring elements 15, 15 is set.
The inner diameter of each of the annular recesses 7, 7 is the diameter of the bottom portion (further, the small diameter portions 23, 23 of the metal bellows 2 to be formed (see FIG. 7).
The diameter of (C) corresponds to the diameter of the bottom of the annular groove 16, 16. Further, a portion of each of the pressing rings 13, 13 which is close to the inner circumference of one side surface and faces the retaining rings 12, 12 has the same sectional shape as one half of each of the retaining rings 12, 12. .

Further, in the illustrated example, each of the ring elements 15 and 1 is
Thickness dimension T of each retaining ring 12, 12
(FIG. 10) is made to coincide with the pitch P (FIG. 7C) of the annular recessed grooves 16, 16 existing on the outer peripheral surface of the metal bellows 2 to be manufactured. Therefore, the intermediate member 8 and each member 1
In the state where 1, 12, 13 are set in the holding cylinder of the pressing device, gaps 17, 17 exist between the holding rings 12, 12 adjacent to each other. In the case of the illustrated example, such retaining rings 12, 12 are provided around the intermediate annular recesses 7, 7 excluding the annular recesses 7, 7 at both ends in the axial direction (the left-right direction in FIG. 10).
One is arranged for each of the annular recesses 7, 7.

On the other hand, each pressing ring 13, 13 has an inner diameter slightly larger than the outer diameter of the cored bar 11. A step portion 18 as shown in detail in FIG. 12 is formed on the inner peripheral edge portions of the surfaces of the pressing rings 13, 13 which face each other. Each step portion 18 has a portion near the opening (a portion near the right side in FIG. 12).
A guide taper portion 19 whose inner diameter increases toward the opening end edge (the right end edge in FIG. 12) is formed, and the back end portion (the left end portion in FIG. 12) is used as the pressing portion 20.

After the intermediate member 8 is set in the holding cylinder together with the respective members 11, 12 and 13 configured as described above as shown in FIG. 10, the intermediate member 8 is plastically deformed and the intermediate member 8 shown in FIG.
In order to obtain the metal bellows 2 as shown in (C), first, the pressing ring 13 on the other side (left side in FIG. 10) is moved toward the pressing ring 13 on the right side in FIG. 10 (right side in FIG. 10). Toward the axial direction)
Press. As a result of this pressing, these pressing rings 13, 13
When the space between them is shortened, as shown in FIG. 13, both ends of the intermediate member 8 in the axial direction (the left-right direction in FIG. 13) extend along the guide taper portion 19 and the step portion 1 of each pressing ring 13, 13 is formed.
Enter into 8 and 18. Then, both ends of the intermediate member 8 are narrowed inward in the diametrical direction with the annular recesses 7, 7 at both ends in the axial direction as fulcrums. As a result, cylindrical portions 21 and 21 having the same outer and inner diameters as those of both ends of the finished metal bellows 2 are formed at both ends of the intermediate member 8 in the axial direction.

From this state, the other pressing ring 13 is further pressed toward the one pressing ring 13, and the distance between the pressing rings 13 and 13 is shortened. The portion between the annular concave portions 7 adjacent to each other in the direction is buckled and deformed, and bulges outward in the diametrical direction of the intermediate member 8. Then, as shown in FIG. 14, if the pressing rings 13 and 13 are brought close to each other until the pressing rings 13 and 12 are sandwiched between the pressing rings 13 and 13, the large diameter portion 22 is obtained. Two
By alternately connecting 2 and the small diameter portions 23, 23, a metal bellows 2 having a corrugated cross-sectional shape in the axial direction is obtained.

Therefore, the metal bellows 2 is attached to the core metal 1
1, the retaining rings 12, 12, and the pressing rings 13, 13 together with the retaining ring 12, and the core metal 11, the retaining rings 12, 12,
By removing the pressing rings 13 and 13, the metal bellows 2 having a desired shape and size can be obtained.

As shown in FIGS. 15 to 16, each retaining ring 1
By matching the cross-sectional shape of the inner peripheral edge of each ring element 15a, 15a constituting 2a, 12a with the cross-sectional shape of the outer peripheral surface of the metal bellows 2 to be manufactured, the shape accuracy and dimensional accuracy of the obtained metal bellows 2 can be improved. To improve it, the above-mentioned Japanese Patent Application No. 5-
No. 296406.

Further, the inner diameters of the cylindrical portions 21 and 21 existing at both ends of the completed metal bellows 2 are set to the small diameter portions 23 and 23.
17 to 19, in order to make the diameter larger than the inner diameter of the intermediate member 8, the annular recess 7 on the outer peripheral surface of the intermediate member 8 manufactured in the first step,
It is also disclosed in the above-mentioned Japanese Patent Application No. 5-296406 that the number of 7 is smaller than that in the first embodiment by 2 places. In this case, in the second step, the retaining rings 12, 12 are arranged around all the annular recesses 7, 7. Further, in the portions of the pair of pressing rings 13a, 13a arranged at both ends in the axial direction (the left-right direction of FIGS. 18 to 19) facing each other, the portions diametrically outward from the opening of the central hole are Cylindrical concave grooves 24, 24 are formed. Each of these grooves 24, 24
The both ends of the intermediate member 8 can be inserted into the plug without rattling. After the members 8, 11, 12, 13a are combined and inserted into the holding cylinder as shown in FIG. 18, if the pressing rings 13a, 13a are brought close to each other as shown in FIG. 19, as shown in FIG. Cylindrical portions 21, 21 having a diameter larger than the portions 23, 23
The metal bellows 2 having

Further, it is also disclosed in Japanese Patent Application No. 5-296406 that the retaining ring 12 (12a) is supported by a support shaft instead of being fitted in the retaining cylinder described above. That is, FIG.
As shown in 0, the outer peripheral portions of the retaining rings 12, 12 are extended outward in the diametrical direction with respect to the pressing rings 13, 13, and in the extended portions, the retaining rings 12, 12 are supported by the support shaft 2.
5, 26 are supported so as to be displaceable in the axial direction (vertical direction in FIG. 20). Each of these support shafts 25 and 26 is arranged in parallel with the cored bar 11. Therefore, with the progress of the second step, the pressing rings 13, 13 (13a, 13a)
When the space between them is shortened, the space between the retaining rings 12, 12 is narrowed, and the metal bellows 2 is molded. By using such a device, the holding rings 12, 12 can be handled more easily than in the case where the holding cylinder is used, and the manufacturing work of the metal bellows 2 can be made more efficient. In addition, in order to make it possible to take out the metal bellows 2 after molding, each of the retaining rings 12, 12 is of a split type,
The support shafts 25 and 26 are movable in the distance.

[0025]

According to the method of manufacturing a metal bellows of the prior invention, which is constructed and operates as described above, a relatively simple and inexpensive equipment is used as compared with the above-mentioned conventional method. It is possible to make highly rigid and highly accurate metal bellows that can be incorporated into steering devices. However,
In order to manufacture a metal bellows of higher quality at a lower cost, the annular recesses 7, 7 are formed on the outer peripheral surface of the raw tube 1 to form the intermediate member 8, which is generated in the first step, as shown in the following It is desired to eliminate such problems.

Since the rotating rollers 9, 9 are moved inward in the diametrical direction of the raw tube 1 while rotating, the supporting mechanism and driving mechanism for these rotating rollers 9, 9 are complicated, and the manufacturing apparatus for the intermediate material 8 is expensive. become. The base pipe 1 is provided with an annular ridge 10, which constitutes the rollers 9, 9.
In order to obtain a high-quality intermediate member 8 and a metal bellows 2 without slip marks, etc., since the annular recesses 7 are formed on the outer peripheral surface of the raw pipe 1 while being rotated by friction with the outer peripheral edge of 10. It is necessary to prevent the outer peripheral surface of the shell 1 and the outer peripheral edges of the annular projections 10 and 10 from slipping. Therefore, it is necessary to finely adjust the rotation speeds of the rollers 9 and 9 and the pressing speed (displacement speed to the inside in the diameter direction) against the raw pipe 1, which makes setting work of the operating condition of the intermediate material 8 troublesome. become. Since the outer peripheral surface of the raw tube 1 and the outer peripheral edges of the annular projections 10 and 10 that form the rollers 9 and 9 are in contact with each other only at narrow portions at a plurality of circumferential positions (three in the illustrated example), The cross-sectional shape of the raw pipe 1 is easily deformed from a perfect circle to an ellipse or the like. Then, when the cross-sectional shape of the obtained intermediate material 8 deviates greatly from the perfect circle, it becomes difficult to mount this intermediate material 8 on the device for performing the second step. When forming the annular recesses 7, 7 in the thin pipe 1 having a small wall thickness, in order to prevent undesired deformation of the hollow pipe 1,
It is necessary to slowly deform the annular recessed portions 7, 7. Therefore, the processing time of the intermediate member 8 becomes long, and the manufacturing efficiency of the metal bellows 2 becomes poor. As a result of performing the processing slowly, the total length L ₂ of the intermediate member 8 may change significantly compared to the total length L _{1 of the} raw tube 1.
If there is a large change and the amount of change varies, the quality of the metal bellows 2 obtained by subjecting the intermediate material 8 to the second step is not stable.

The method and apparatus for manufacturing an intermediate material for manufacturing a metal bellows according to the present invention is intended to eliminate the above-mentioned problems 1 to 3 and manufacture a metal bellows of higher quality at a lower cost. .

[0028]

[MEANS FOR SOLVING THE PROBLEMS] Among the manufacturing method and manufacturing apparatus of the metal bellows manufacturing intermediate material of the present invention, the invention of the manufacturing method of the metal bellows manufacturing intermediate material according to claim 1 is plastic deformation. On the outer peripheral surface of a cylindrical body made of a flexible metal plate, a plurality of annular recesses, each of which extends over the entire circumference of the cylindrical body, are intermittently formed in the axial direction of the cylindrical body to form a metal pipe. In order to manufacture an intermediate material for manufacturing a bellows, a split die composed of a die element that is circumferentially divided into three or more pieces and is provided with a ridge at a portion corresponding to the annular recess around the raw tube. After arranging, the respective die elements are simultaneously displaced toward the inner side in the diametrical direction of the raw tube, and the distal end edges of the respective protrusions which are arc-shaped to match the circumferential shape of the bottom of the annular recesses are Butt against the outer peripheral surface of the raw pipe, It is plastically deformed to form a plurality of annular recesses.

The invention of the apparatus for manufacturing an intermediate material for manufacturing a metal bellows according to a second aspect of the invention is a mounting table for supporting a cylindrical tube made of a plastically deformable metal plate.
Three or more displacement blocks that are arranged around the tube placed on the mounting table in a radial direction centered on the tube and that move simultaneously toward and away from the outer peripheral surface of the tube, and each displacement block. Dice elements fixed to the inner peripheral side surface of the block, intermittently provided on the inner peripheral side surface of each die element over the axial direction of the raw pipe, each of the leading edge to the outer peripheral surface of the raw pipe A plurality of arcuate projections that match the circumferential shape of the bottom of the annular recess to be formed.

[0030]

According to the method and apparatus for manufacturing an intermediate material for manufacturing a metal bellows of the present invention configured as described above, a ridge provided on a die element divided into three or more pieces in the circumferential direction. The tip edges of the above are abutted against a plurality of positions in the axial direction of the outer peripheral surface of the base pipe over substantially the entire length of the outer peripheral surface of the base pipe to form annular recesses at the plurality of positions at the same time. Therefore, compared with the specific example of the first step described in the specification of the previous invention, the following excellent effects can be obtained.

Since each die element only moves in parallel in the diametrical direction of the raw pipe, the supporting mechanism and the driving mechanism of each die element can be realized with a simple structure, and the manufacturing apparatus of the intermediate material becomes inexpensive. Since the outer peripheral surface of the raw pipe is pressed by the ridges of each die element and hardly slips, a high quality intermediate material without slip marks etc. is set without particularly troublesome operating conditions setting. And a metal bellows can be obtained. Since the portion where the annular recess is formed on the outer peripheral surface of the base pipe is restrained by the protrusion of each die over substantially the entire circumference, the cross-sectional shape of the base pipe is maintained as a perfect circle. Therefore, the obtained intermediate material can be easily attached to the device for performing the second step. Since the portion where the annular recess is formed on the outer peripheral surface of the raw pipe is restrained over the entire circumference by the protrusion of each die, even if the annular recess is formed in the thin pipe in a short time, this Undesirable deformation does not occur in the tube. Therefore, it is possible to shorten the processing time of the intermediate material and improve the manufacturing efficiency of the metal bellows. As a result of processing the raw pipe in a short time, the total length of the intermediate material hardly changes compared to the total length of the raw pipe, and even if no adjustment process is provided after manufacturing the intermediate material, the intermediate material can be further processed in the second step. The quality of the metal bellows obtained by processing is stable.

[0032]

1 to 4 show an embodiment of an apparatus for producing an intermediate material for producing a metal bellows according to the present invention. Fixed board 2
On the upper surface of 7, a lower slide holder 28 and a plurality of screws 5
It is fixed by 9. A convex portion 29 is formed at the center of the upper surface of the lower slide holder 28.
A plurality of (12 in the illustrated example) guide grooves 30 on the upper surface of the
30 is formed in the radial direction. Then, the displacement blocks 31, 3 are respectively provided in the guide groove 30, 30, respectively.
The lower end of 1 is engaged slidably in the radial direction. Further, a notch 32 is formed in the peripheral portion of the convex portion 29 at a portion facing the outer end portion of each of the guide concave grooves 30, 30. Then, the displacement side locking pin 3 fixed to the bottom surface of the outer end portion of each of the displacement blocks 31, 31.
3, 33 are located inside each of the notches 32. The displacement side locking pins 33, 33 and the fixed side locking pins 34, 3 fixed to the peripheral portion of the substrate 27 are provided.
4, and tension springs 35 and 35 are provided between them. Therefore, as long as no external force acts, each of the displacement blocks 31 and 31 has the substrate 2 as shown in the right half of FIG.
7 is in a state of being displaced outward in the diametrical direction.

A cylindrical guide tube 36 is provided on the upper surface of the substrate 27 and around the lower slide holder 28.
Are fixed by a plurality of bolts 37, 37. A flange 38 is provided on the inner peripheral surface of the upper end of the guide cylinder 36,
The lower end portion of the holder cylinder 40, which will be described below, is prevented from slipping upward from the upper end opening of the guide cylinder 36. The tension springs 35, 35 are bridged between the displacement side, the fixed side, and the locking pins 33, 34 through a through hole 39 provided in a part of the guide cylinder 36.

The lower end of the cylindrical holder cylinder 40 is inserted into the upper part of the guide cylinder 36 through the inside of the flange 38. A ring-shaped locking plate 41 is fixed to the lower surface of the holder cylinder 40 by a plurality of screws 42.
The outer diameter of the locking plate 41 is smaller than the inner diameter of the main body portion of the guide cylinder 36 and larger than the inner diameter of the collar portion 38. Therefore, the locking plate 41 allows the holder cylinder 40 to move up and down, but restricts the upward displacement of the holder cylinder 40 based on the engagement with the flange portion 38. In addition, the guide pins 4 are provided vertically on the lower surface of the locking plate 41.
Guide tubes 44, in which 3, 43 are planted at a plurality of locations (four locations in the illustrated example) near the outer periphery of the upper surface of the substrate 27,
It is inserted in 44 through a ball without rattling.
Therefore, the holder cylinder 40 is supported above the substrate 27 so as to be movable up and down without rattling.

A ring-shaped upper plate 45 is fixed to the upper end surface of the holder cylinder 40 by a plurality of bolts 46. Then, a plurality of cam plates 47, 47 laid over the inner peripheral surface of the holder cylinder 40 and the lower surface of the upper plate 45.
Are fixed in the radial direction by a plurality of screws 48, 48, respectively.

Each of the cam plates 47, 47 is formed in the shape of a right triangle, and is fixed to the holder cylinder 40 and the upper plate 45 with the inclined surfaces 49, 49 facing the inner peripheral side. ing. In addition, the displacement blocks 31 and 31 are also
The cam plates 47, 47 are formed in a right-angled triangular shape similar to the above-mentioned cam plates 47, and their inclined surfaces 50, 50 are directed to the outer peripheral side. In the case of the illustrated embodiment, the cam plates 47, 47
Concave grooves 51, 51 are formed in the widthwise central portions of the inclined surfaces 49, 49 of the inclined surfaces 50, 49 of the displacement blocks 31, 31.
A portion 50 is slidably engaged with each of the grooves 51, 51. Therefore, the displacement blocks 31, 31 are
As the cam plates 47, 47 are lowered, they are displaced inward in the diametrical direction against the elasticity of the tension springs 35, 35.

Each displacement block 3 constructed as described above
Dice elements 58, 58 for forming a split die are coupled and fixed to the inner peripheral side surfaces of 1, 31 by keys 52, 52 and screws 53, 53, respectively. A plurality of ridges 54, 54 are provided on the inner peripheral side surface of each of these dice elements 58, 58.
Are intermittently provided in the axial direction (the vertical direction of FIGS. 1 and 2 and the front and back directions of FIGS. 3 and 4) of the raw pipe 1 which is the workpiece. That is, each of these ridges 54, 54 corresponds to the pitch of the annular recesses 7, 7 on the outer peripheral surface of the intermediate member 8 produced by processing the above-mentioned raw pipe 1, and the annular recesses 7 for each die element 58, 58. , 7 are provided for each. Further, the tip edges of the protrusions 54, 54 have an arc shape that matches the circumferential shape of the bottoms of the annular recesses 7, 7.

Further, a through hole 55 reaching the substrate 27 is formed in the central portion of the lower slide holder 28 in the vertical direction. A column-shaped mounting table 57 is fixed to the upper end portion of the rod 56 that is vertically inserted through the through hole 55. When the intermediate member 8 is manufactured, the raw tube 1 which is a workpiece is placed on the upper surface of the placing table 57.

In order to carry out the method for producing an intermediate material for producing a metal bellows according to the present invention, when the raw pipe 1 is processed into the intermediate material 8 by using the production apparatus configured as described above, first, With the mounting table 57 at the upper end of the rod 56 being lowered, the base tube 1 is mounted on the upper surface of the mounting table 57 as shown in the right half of FIGS. In this state, the cam plates 47, 47 are located at the upper end position, and the displacement blocks 31, 31 and the die element 5 fixed to the inner peripheral side surface of each displacement block 31, 31.
8, 58 remain displaced diametrically outward. Therefore, the work of inserting the element pipe 1 between the die elements 58, 58 is performed by the protrusions 54, 5 of the die elements 58, 58.
Easy to do without being disturbed by 4.

As shown in the right half of FIGS.
Is inserted in a predetermined position, the upper surface of the upper plate 45 is
By pressing with a ram or the like of a press machine, each cam plate 4 described above
7 and 47 are lowered. As a result, the inclined surfaces 49, 5
Based on the sliding of 0s, the above displacement blocks 31, 31
Is displaced inward in the diametrical direction. Then, as shown in the left half of FIGS.
The tip ends of 4, 54 are abutted against the outer peripheral surface of the raw tube 1, and annular recesses 7, 7 are formed in the corresponding portions to form an intermediate member 8.

As described above, according to the method and the apparatus for manufacturing the intermediate material for manufacturing the metal bellows of the present invention, the ridges 54, 5 provided on the die elements 58, 58 divided in the circumferential direction.
4 in the axial direction of the outer peripheral surface of the shell 1 (vertical direction in FIGS. 1-2, front-back direction in FIGS. 3-4) at a plurality of positions (in the case of the illustrated example,
14), and the annular recesses 7, 7 are simultaneously formed at the plurality of positions by abutting the outer peripheral surface of the raw tube 1 over substantially the entire length. After the annular recesses 7, 7 are formed in this way, if the force pressing the upper surface of the upper plate 45 is released, the displacement blocks 31, 31 are pulled by the tension springs 3.
The cam plates 47, 47 are lifted by the elastic forces of 5, 35 to return to the outside in the diametrical direction. The intermediate member 8 processed from the raw tube 1 in this manner is the plurality of die elements 58, 58.
Take out from between and send to the next process. Then, the metal bellows 2 is obtained by performing the above-mentioned second step of the invention.
And

Although not shown, a compression spring is provided between the lower surface of the locking plate 41 and the upper surface of the lower slide holder 28, and the holder cylinder 40 and the cam plate 47 fixed to the locking plate 41 are provided. , 47, etc., so that the displacement blocks 31, 31 can be smoothly restored by the tension springs 35, 35. Also, an appropriate cored bar can be inserted inside the raw tube 1 which is the workpiece. Further, a lubricating device for lubricating each sliding portion, and a knockout mechanism for putting the raw material tube 1 or the intermediate material 8 in and out of the working position can be appropriately mounted as necessary.

Also, a slight gap is formed between the circumferential ends of the protrusions 54, 54 formed on the die elements 58, 58 adjacent to each other in the circumferential direction. The shape error of the annular recesses 7, 7 due to the gap does not affect the working operation of the metal bellows 2 in the second step and can be ignored. However, the annular concave portion 7 without any shape error,
If it is necessary to make 7, it is possible to eliminate the shape error due to the above gaps by slightly shifting the phase in the circumferential direction and performing the processing twice.

[0044]

According to the method and apparatus for manufacturing an intermediate material for manufacturing a metal bellows of the present invention, since each die element only moves in parallel in the diametrical direction of the raw pipe, a supporting mechanism and a driving mechanism for each die element. Can be realized with a simple structure, and the manufacturing equipment of the intermediate material becomes inexpensive. Since the outer peripheral surface of the raw pipe is pressed by the ridges of each die element and hardly slips, a high quality intermediate material without slip marks etc. is set without particularly troublesome operating conditions setting. And a metal bellows can be obtained. Since the portion where the annular recess is formed on the outer peripheral surface of the base pipe is restrained by the protrusion of each die over substantially the entire circumference, the cross-sectional shape of the base pipe is maintained as a perfect circle. Therefore, the obtained intermediate material can be easily attached to the device for performing the second step. Since the portion where the annular recess is formed on the outer peripheral surface of the raw pipe is restrained over the entire circumference by the protrusion of each die, even if the annular recess is formed in the thin pipe in a short time, this Undesirable deformation does not occur in the tube. Therefore, it is possible to shorten the processing time of the intermediate material and improve the manufacturing efficiency of the metal bellows. As a result of processing the raw pipe in a short time, the total length of the intermediate material hardly changes compared to the total length of the raw pipe, and even if no adjustment process is provided after manufacturing the intermediate material, the intermediate material can be further processed in the second step. The quality of the metal bellows obtained by processing is stable.
Therefore, it is possible to manufacture a metal bellows of higher quality at a lower cost while maintaining the effects of the above-described invention as it is.

[Brief description of drawings]

1 shows an embodiment of the manufacturing apparatus of the present invention, A- in FIG.
A sectional view.

FIG. 2 is an enlarged view of a central portion of FIG.

3 is a sectional view taken along line BB of FIG.

FIG. 4 is an enlarged view of a central portion of FIG.

FIG. 5 is a sectional view showing a first example of a conventional method.

FIG. 6 is a sectional view showing a second example of the same.

7A and 7B are a cross-sectional view and an end view showing changes in the shape of a member in the prior invention in the order of steps.

FIG. 8 is a view corresponding to a CC cross section of FIG. 9, showing the first example of the implementation state of the first step.

9 is a side view of FIG. 8.

FIG. 10 is a cross-sectional view showing a state at the start of the second step in the first example.

11 is a view of the retaining ring viewed from the side in FIG.

FIG. 12 is an enlarged view of the left part of FIG.

FIG. 13 is a sectional view showing a state in the middle of the second step in the first example.

FIG. 14 is a sectional view at the end of the second step.

FIG. 15 is a cross-sectional view showing a state at the start of the second step in the second example of the prior invention.

FIG. 16 is a sectional view at the end of the second step.

FIG. 17 is a sectional view of a metal bellows manufactured according to a third example of the prior invention.

FIG. 18 is a sectional view showing a state in the middle of the second step in the third example.

FIG. 19 is a sectional view at the end of the second step.

FIG. 20 is a vertical cross-sectional view showing another example of the manufacturing apparatus in the prior invention in a state at the end of the second step.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Element pipe 2 Metal bellows 3 Molding cylinders 4a, 4b Molding piston 5 Retaining ring 6 High frequency induction coil 7 Annular recess 8 Intermediate material 9 Rotating roller 10 Annular ridge 11 Core bar 12, 12a Retaining ring 13, 13a Pressing ring 14 Tapered Tapered part 15, 15a Ring element 16 Annular groove 17 Gap 18 Step 19 Guide taper part 20 Pressing part 21 Cylindrical part 22 Large diameter part 23 Small diameter part 24 Recessed groove 25, 26 Support shaft 27 Base plate 28 Lower slide holder 29 Convex part 30 Guide concave groove 31 Displacement block 32 Notch 33 Displacement side locking pin 34 Fixed side locking pin 35 Extension spring 36 Guide tube 37 Bolt 38 Collar part 39 Through hole 40 Holder tube 41 Locking plate 42 Screw 43 Guide pin 44 Guide Cylinder 45 Upper plate 46 Bolt 47 Cam plate 48 Screws 49, 50 Inclined surface 51 Recessed groove 52 key 53 screw 54 ridge 55 through hole 56 rod 57 mounting table 58 die element 59 screw

Claims (2)

[Claims] 1. A plurality of annular recesses are formed on the outer peripheral surface of a cylindrical body made of a plastically deformable metal plate so as to extend along the entire circumference of the cylindrical body. To form an intermediate material for manufacturing a metal bellows, the die is divided into three or more pieces in the circumferential direction around the element pipe, and a ridge is provided at a portion corresponding to the annular recess. After arranging the split dies constituted by the elements, the respective die elements are simultaneously displaced inward in the diametrical direction of the raw pipe, and each of the arc shapes is matched with the circumferential shape of the bottom of each annular recess. A method for manufacturing an intermediate material for manufacturing a metal bellows, comprising a step of abutting a tip edge of a ridge against an outer peripheral surface of the raw pipe to plastically deform a part of the raw pipe inward in a radial direction to form the plurality of annular recesses. 2. A mounting table for supporting a cylindrical tube made of a plastically deformable metal plate and radiation around the cylindrical tube placed on the mounting table. The three or more displacement blocks that are arranged in the same direction and move in the same direction as the outer peripheral surface of the tube at the same time, the die element fixed to the inner peripheral side surface of each displacement block, and the inner peripheral side surface of each die element. A plurality of arc-shaped arcs which are provided intermittently in the axial direction of the base pipe and have their respective leading edges aligned with the circumferential shape of the bottom of the annular recess to be formed on the outer peripheral surface of the base pipe. An apparatus for manufacturing an intermediate material for manufacturing a metal bellows, which includes a ridge.