JP2001105081A - Closed forging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a closed forging apparatus having simple structure and small energy loss. SOLUTION: In the closed forging apparatus which performs forging by closing a forming chamber 31 formed in the mating surface parts of an upper and a lower dies 43, 30 by bringing both dies 43, 30 in press contact, a closing device 33 for closing the forming chamber 31 supports at least the die 30 with a supporting plate 24 so as to be vertically movable. A number of compressive deformable elastic bodies 37 are arranged in parallel between the outer peripheral part of the supporting plate 24 and the outer peripheral part of the die 30 and the pressurized contact force of the upper and the lower dies 43, 30, generated by these elastic bodies 37 is used for the pressurized contact force needed to the closed forging.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a closed forging device for closing a molding chamber formed at a mating surface between upper and lower dies and plastically deforming a material in the molding chamber into a predetermined shape in this state.

[0002]

2. Description of the Related Art As a conventional technique, Japanese Utility Model Publication No. 7-13887.
No. 2, that is, the one described in FIG. In FIG. 4, reference numeral 1 denotes a bolster, and 2 denotes a slide which is moved up and down with respect to the bolster 1. An upper die 5 is mounted on the lower surface of the slide 2 via an upper die set 4 and a hard plate 4a. The upper punch 6 is accommodated in 5. A lower die 7 is attached to the upper surface of the bolster 1 via a lower die set 8 so as to be slidable up and down.
And the lower punch 10. A cavity 16 is formed in the mating surface of the upper die 5 and the lower die 7.

[0003] A cushion cylinder 12 is mounted below the lower die 7. A piston 12b that can move up and down along a central axis 12a is housed inside the cushion cylinder 12, and a hydraulic pressure is supplied to a lower hydraulic chamber 12c. Also,
Six pins 13 are arranged on the upper surface plate of the cushion cylinder 12 on the same circumference so as to be slidable up and down, and the lower surface thereof is in contact with the upper surface of the piston 12b, and the upper surface is the lower surface of the lower die 7. Face to face. Further, a plurality of spring chambers 7a are formed on the outer peripheral portion in the lower die 7, and the compression springs 14 are accommodated in the spring chambers 7a, and the lower ends thereof are brought into contact with the upper surface plate of the cushion cylinder 12. The lifting force of the lower die 7 due to the hydraulic pressure of the hydraulic chamber 12 c is made sufficiently larger than the lifting force of the compression spring 14. In addition, 15 is a stopper for setting the ascending position of the lower die 7, and 17 is an eject pin for projecting a molded product.

In the initial stage of forging, where the closing force may be small, the closed state of the upper die 5 and the lower die 7 is maintained by the spring force of the compression spring 14, and then, in the latter stage of forging requiring a large closing force, the hydraulic chamber is provided. The upper die 5 and the lower die 7 are closed and held by a large force by the hydraulic pressure of 12c.

[0005]

In the prior art, the upper die 5 and the lower die 7 are closed by a hydraulic device, so that the structure becomes complicated and expensive, and the pump and oil It required auxiliary equipment such as tanks, and was large. SUMMARY OF THE INVENTION An object of the present invention is to provide a new closed forging device that solves the above-mentioned disadvantages by closing the upper and lower dies only by the elastic force of the elastic body.

[0006]

Means for Solving the Problems The present invention is configured as follows to achieve the above object. That is, the invention of claim 1 is a closing device that presses the upper and lower dies to close the molding chamber formed at the mating surface of the upper and lower dies, and pressurizes the material in the molding chamber while the molding chamber is closed. A closing forging device having a punch for plastically deforming a material along a molding surface, wherein the closing device supports at least one of the dies on a support plate so as to be vertically movable, and has an outer peripheral portion of the support plate and an outer periphery of the die. A large number of compressively deformable elastic bodies are provided in parallel with the portion, and the pressing force of the elastic bodies on the upper and lower dies is set as the pressing force required for closed forging. Further, according to the invention of claim 2, as the closing device, the upper and lower dies are respectively supported at the center of the upper and lower support plates so as to be vertically movable, and between the outer periphery of each support plate and the outer periphery of the upper and lower dies. A large number of upper and lower elastic bodies that can be compressed and deformed are provided in parallel, and the upper and lower elastic bodies have different stroke lengths of the upper and lower dies. Further, in the invention according to claim 3, the closing device is configured to support at least one of the dies so as to be vertically movable at a center portion of a support plate, and a spring that opposes the outer periphery of the support plate at the outer periphery of the one die. A receiving plate is provided, and a number of vertically extending guide posts are provided in parallel on the spring receiving plate and the outer peripheral portion of the support plate, and a number of metal disc springs are fitted to each guide post while being turned up and down. And the pressing force of the disc spring against the upper and lower dies is the pressing force required for closed forging. The invention according to claim 4 is such that an intermediate spring receiver is fitted to an intermediate portion of each of the guide posts so as to be slidable up and down, and a large number of metallic members are provided between one end of each guide post and the intermediate spring receiver. A disc spring is turned upside down and fitted, and a metal coil spring having a smaller elastic force than the disc spring is provided between the other end of each guide post and the intermediate spring receiver, and overcompression of the coil spring. This is configured to provide a restricting body for preventing the above.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. In the drawings, FIG. 1 is an explanatory sectional view showing a first embodiment of the present invention, FIG. 2 is an explanatory sectional view showing a second embodiment of the present invention, and FIG. 3 is an explanatory view showing a third embodiment of the present invention. FIG.

In FIG. 1, reference numeral 20 denotes a closed forging device;
Is the base, and the lower die unit 2
Attach 2. That is, a disc-shaped pressure plate 23 and a support plate 24 surrounding the outer periphery of the pressure plate 23 are attached to the upper surface of the base 21, and the center block 25 is fixed to the upper surface of the pressure plate 23. The lower punch 26 is fitted to the center of the center block 25 so as to be slidable up and down, and the lower end thereof is brought into contact with the upper surface of the center of the pressure plate 23. The ejector pin 27 to be pressed and moved is fitted.

A holding ring 28 is fitted to the outer periphery of the center block 25 so as to be slidable up and down.
A large-diameter spring receiving plate 29 is fixed to the upper flange portion. The lower die 30 is attached to the center of the spring receiving plate 29.
And a molding chamber 31 is formed in the center of the lower die 30. The molding chamber 31 penetrates the center of the lower die 30 with a hole having a circular cross section, and has large-diameter gear molding teeth on the upper surface thereof. 26 are slidably fitted, and a columnar work A is fitted on the upper side.

A closing device 33 is provided between the support plate 24 and the spring receiving plate 29. That is, for example, ten guide posts 34 in which a number of metal disc springs (elastic bodies) 37 are fitted between the outer peripheral portion of the support plate 24 and the outer peripheral portion of the spring receiving plate 29 are arranged in the circumferential direction. And arranged at predetermined intervals in the radial direction, the lower end of which is inserted into the support plate 24 with a stepped small-diameter shaft 34a. The upper part is slidably penetrated through the spring receiving plate 29 to be exposed to the upper part, and a stopper bolt 36 for a stopper is screwed to the exposed end.

As shown in FIG. 1, the disc springs 37 fitted to the respective guide posts 34 are turned upside down and overlapped with each other. And the repulsive force of each disc spring 37, that is, the closing device 33 is set to be a repulsive force necessary for closed forging. That is, the spring constant of one disc spring 37, the number of vertically stacked disc springs 37, the number of sets in the circumferential direction, and the like are selected and set.

The upper die unit 4 is provided above the base 21.
0 is provided. That is, a pressing body 42 is attached to the center of a housing 41 which is moved up and down by a ram (not shown), and an upper die 43 serving as an upper punch is provided at the center of the lower surface of the pressing body 42.
And suspended from the housing 41 via the holder 44 and the suspension nut 45. The upper die 43 faces the center of the lower die 30 described above, and has an upper molding surface 43a that is recessed in a shallow container shape at the center of the lower surface. The holder 44 has a skirt portion 44a protruding downward on the outer periphery thereof.
And the lower die 3 described above is attached to the skirt portion 44a.
0 can be fitted at the top.

According to the first embodiment, after the cylindrical work A is fitted into the molding chamber 31, the upper die unit 40
Is lowered, first, as shown in the left half of FIG. 1, the outer peripheral portion of the upper die 43 contacts the outer peripheral surface of the upper surface of the lower die 30,
The molding chamber 31 is closed. In this state, the upper die unit 40
Is lowered to the lower limit, as shown in the right half of the figure, the lower die 30 is pushed down against the reaction force of the disc spring 37 at the outer peripheral portion of the upper die 43 (the closed state of the molding chamber 31 is maintained). At the same time, the work A is axially compressed and plastically deformed by the upper molding surface 43a and the lower punch 26, so that a product A-1 having large-diameter gear teeth at the upper end is formed.

In this case, the press-contact force between the upper die 43 and the lower die 30 increases as the two die move downward, and the reaction force of the disc spring 37 increases. This means that in the initial stage of forging, where the amount of plastic deformation of the work A is small, the reaction force of the disc spring 37 is small and energy loss is reduced, and the amount of plastic deformation of the work A increases, and the material is brought into contact with the upper and lower dies 43 and 30. In the final stage of forging (the time when the product A-1 is completed), the press-contact force between them, that is, the closing force of the molding chamber 31, is increased most, and the generation of burrs at the mating surfaces of the upper and lower dies 43, 30 is suppressed. become. Therefore, the product A-
1 can be obtained efficiently. The above-mentioned disc spring 37
May be replaced with rubber or resin having elasticity.

FIG. 2 shows a second embodiment. In FIG.
22 is a lower die unit substantially similar to the first embodiment described above,
40-1 is an upper die unit. Upper die unit 4
0-1 attaches a disc-shaped upper pressure plate 50 and an upper support plate 51 surrounding the outer periphery of the upper pressure plate 50 to the lower surface of a movable base (both not shown) moved up and down by a ram;
The upper center block 52 is fixed to the lower surface of the upper pressure plate 50. An upper punch 5 is provided at the center of the upper center block 52.
An upper ejector pin 54 for pressing the upper punch 53 downward on the central portion of the upper pressure plate 50 by fitting the upper punch 3 downwardly and slidably and vertically so that the upper end thereof abuts against the lower surface of the central portion of the upper pressure plate 50. Is fitted.

An upper holding ring 55 is fitted to the outer periphery of the upper center block 52 so as to be vertically slidable, and a large-diameter upper spring receiving plate 5 is fitted to a lower flange portion of the upper holding ring 55.
6 is fixed. An upper die 57 facing the lower die 30 is fitted and fixed to the center of the upper spring receiving plate 56, and a molding chamber 31 ′ facing the molding chamber 31 of the lower die 30 is formed in the center of the upper die 57. . This molding chamber 31 ′ has an upper die 57.
Is penetrated by a hole having a circular cross section, the upper punch 53 described above is slidably fitted to the upper side, and the columnar work A is fitted to the lower side.

An upper closing device 60 is provided between the upper support plate 51 and the upper spring receiving plate 56. That is, for example, ten upper guide posts 62 in which a number of metal upper disc springs (elastic bodies) 61 are fitted between the outer peripheral portion of the upper support plate 51 and the outer peripheral portion of the upper spring receiving plate 56. Are arranged at predetermined intervals in the circumferential direction and the radial direction, the upper end of which is inserted into the upper support plate 51 with a stepped small diameter shaft 62a, and a tightening bolt 63 is screwed to the upper end. The lower part is fixed to the upper support plate 51, the lower part thereof is slidably penetrated through the upper spring receiving plate 56 to be exposed at the lower part, and a stop bolt 64 for a stopper is screwed to the exposed end.

The length of each upper guide post 62 is about twice as long as the length of the guide post 34 on the lower die unit 22 side. Disc spring 3 fitted to post 34
7, the upper die 5 is formed by the upper disc spring 61, that is, the upper closing device 60.
7 with the closing device 33 (disc spring 3
The stroke length of the lower die 30 according to 7) is about twice as long. The other structure is substantially the same as that of the first embodiment.

According to the second embodiment, after the cylindrical work A is fitted into the molding chamber 31 on the lower die unit 22 side, when the upper die unit 40-1 descends, first, as shown in FIG. As shown in the left half, the upper punch 53 contacts the upper surface of the work A in a state where the molding chamber 31 (31 ') is open.
When the upper die unit 40-1 further descends in this state, the work A is compressed in the axial direction by the upper and lower punches 53 and 26, and the middle part in the vertical direction starts to plastically deform (bulge), and this plastic deformation is reduced by a predetermined amount. Then, the outer peripheral portion of the upper die 57 contacts the outer peripheral surface of the upper surface of the lower die 30 to form the molding chambers 31 and 3.
Close 1 '.

When the upper die unit 40-1 further descends in this state, the upper die 57 moves in the retreating direction (toward the upper center block 52) due to the deformation of the upper disc springs 61, and the lower disc springs move. The plastic deformation of the work A progresses while moving at approximately twice the speed of the retreating direction of the die 30 (direction of the lower center block 25) due to the deformation of the die 37, and the upper die unit 40-1 reaches the lower limit. When moved, a product A-2 having large-diameter gear teeth is formed at the middle part in the vertical direction, as shown in the right half of FIG.

In the second embodiment, as in the first embodiment, the pressing force of the upper and lower dies 57, 30 during forging, that is, the closing force of the molding chambers 31, 31 'is changed from the initial stage to the final stage. Can be progressively larger. In addition, the movement of the upper die 57 in the retreating direction during forging is performed by the lower die 30.
The material flow of the work A at the time of forging flows almost evenly from the upper and lower ends to the upper and lower intermediate portions, and the large diameter of the large diameter material flows to the upper and lower intermediate portions at the time of forging. The product A-2 having gear teeth can be formed with high precision.

The ratio between the stroke length of the upper die 57 and the stroke length of the lower die 30 according to the second embodiment is 2: 1, but this ratio is 2.5: 1 or 3: 1. It is set appropriately depending on the shape of the product to be molded. In this case, the stroke length ratio is set by changing the number of layers of the upper disc spring 61 and the lower disc spring 37, the number of sets in the circumferential direction, and the like. Further, the stroke length of the lower die 30 may be longer than the stroke length of the upper die 57.

FIG. 3 shows a third embodiment. In FIG.
40 is an upper die unit substantially similar to the first embodiment described above,
22-1 is a lower die unit. Reference numeral 33-1 denotes a closing device for the lower die unit 22-1, which is as follows. That is, for example, ten guide posts 34 are arranged at predetermined intervals in the circumferential direction and the radial direction between the outer peripheral portion of the support plate 24 and the outer peripheral portion of the spring receiving plate 29, and the lower end is supported. It is fixed to the plate 24, the upper part thereof is slidably penetrated through the spring receiving plate 29 to be exposed to the upper part, and a stopper bolt 36 for a stopper is screwed to the exposed end.

An intermediate spring receiver 38 is vertically slidably fitted to an intermediate portion of each of the guide posts 34 in the vertical direction, and a number of metal disc springs 37a are turned up and down on the lower side of each guide post 34. And the lowermost disc spring 37a is brought into contact with the upper surface of the support plate 24, and the uppermost disc spring 37a is brought into contact with the lower surface of the intermediate spring receiver 38. A metal coil spring 3 having a smaller elastic force than the disc spring 37a is provided on the upper side of each guide post.
7b, the lower end thereof is brought into contact with the upper surface of the intermediate spring receiver 38, and the upper end thereof is brought into contact with the lower surface of the spring receiving plate 29. Also, the intermediate spring receiver 38
A cylindrical regulating body 39 is attached to the outer periphery of the upper part of the cylinder. The restricting body 39 prevents overcompression of the coil spring 37b, and is slightly longer than the length of the coil spring 37b when it is in close contact. The other structure is substantially the same as that of the first embodiment.

According to the third embodiment, after the columnar work A is fitted into the molding chamber 31 on the lower die unit 22-1 side, when the upper die unit 40 descends, first, FIG. As shown in the left half, the outer peripheral portion of the upper die 43 contacts the outer peripheral surface of the upper surface of the lower die 30 to close the molding chamber 31. When the upper die unit 40 further descends in this state, first, the coil spring 37b having a weak spring force bends first, and until the regulating body 39 comes into contact with the spring receiving plate 29, the reaction force of the coil spring 37b causes the above-mentioned molding chamber to be bent. The work A is plastically deformed in a state where the work 31 is closed with a small force. When the upper die unit 40 further descends after the restricting body 39 contacts the spring receiving plate 29, each of the lower disc springs 37a
When the upper die unit 40 moves to the lower limit while the plastic deformation of the work A proceeds while bending, a product A-3 having large-diameter gear teeth on the upper portion is formed as shown in the right half of FIG. Will be.

In the third embodiment, as in the first and second embodiments, the pressing force of the upper and lower dies 43 and 30 during forging, that is, the closing force of the molding chamber 31 increases from the initial stage to the final stage. In addition to the simple structure, a high quality product A-3 can be efficiently obtained, and the closing force may be small in the initial stage of forging, but when a forged product having a large vertical movement amount is obtained, energy loss is required. Can be reduced.

[0027]

As is apparent from the above description, claim 1
According to the invention, one of the dies supported vertically movably on a support plate is pressed against the other die with an elastic body capable of being deformed by compression, and the molding chamber divided vertically by only the reaction force of the elastic body is closed. As a result, the structure becomes simple and inexpensive, and the closing force of the molding chamber can be gradually increased from the initial stage to the final stage of forging, so that energy loss is reduced and high quality products can be efficiently produced. Obtainable. Further, the invention according to claim 2 uses a large number of metal disc springs as the elastic body of the closing device,
The molding chamber can be closed with a large force at the final stage of forging. In the invention according to claim 3, a disc spring having a large elastic force and a coil spring having a small elastic force are arranged in series, and a regulating member for preventing overcompression of the coil spring is provided. The closing of the forming chamber at the time is mainly covered by a coil spring having a small elastic force, and the closing of the forming chamber at the final stage of forging is covered by a disc spring having a large elastic force, thereby efficiently forming a forged product requiring a large stroke length. be able to.

[Brief description of the drawings]

FIG. 1 is an explanatory sectional view showing a first embodiment of the present invention.

FIG. 2 is an explanatory sectional view showing a second embodiment of the present invention.

FIG. 3 is an explanatory sectional view showing a third embodiment of the present invention.

FIG. 4 is a cross-sectional view according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 20 Closed forging apparatus 21 Base 22 (22-1) Lower die unit 23 Pressure plate 24 Support plate 25 Center block 26 Lower punch 27 Ejector pin 28 Retaining ring 29 Spring receiving plate 30 Lower die 30a Clamp 31 (31 ') Molding room 33 (33-1) Closing device 34 Guide post 34a Small diameter shaft 35 Tightening bolt 36 Locking bolt 37 (37a) Belleville spring 37b Coil spring 38 Intermediate spring receiver 39 Regulator 40 Upper die unit 41 Housing 42 Pressing body 43 Upper die 43a Upper molding surface 44 Holder 45 Hanging nut 40-1 Upper die unit 50 Upper pressure plate 51 Upper support plate 52 Upper center block 53 Upper punch 54 Upper ejector pin 55 Upper holding ring 56 Upper spring receiving plate 57 Upper die 60 Upper closing device 1 upper disc spring 62 on the guide posts 62a small-diameter shaft 63 clamping bolt 64 bolt

Claims (4)

[Claims] A molding chamber (3) formed by press-contacting upper and lower dies (43, 30) at a mating surface of the upper and lower dies (43, 30).
1) a closing device (33) for closing the molding chamber (3);
Work (A) in molding chamber (31) with 1) closed
And a punch (26, 43) for plastically deforming the work (A) along the molding surface by pressurizing the work (A), wherein the closing device (33) includes at least one die (30) supporting a support plate. An elastic body (3) which is vertically movably supported by the (24) and is compressively deformable between the outer peripheral portion of the support plate (24) and the outer peripheral portion of the one die (30).
7) A closed forging device, wherein a large number of 7) are provided in parallel, and the pressing force of the elastic body (37) on the upper and lower dies (43, 30) is the pressing force required for closed forging. 2. The closing device (60, 33) includes an upper die (57, 30) and an upper support plate (5).
, 24) so as to be able to move up and down, and the outer periphery of each support plate (51, 24) and the upper and lower dies (57, 24).
A large number of upper and lower elastic bodies (61, 37) that can be compressed and deformed are provided in parallel with the outer periphery of the upper and lower dies (57, 30) by the upper and lower elastic bodies (61, 37).
The closed forging device according to claim 1, wherein the stroke lengths of the forgings are different from each other. 3. The closing device (33) supports at least one of the dies (30) up and down at the center of a support plate (24), and supports the at least one die (30) on the outer periphery of the one die (30). A spring receiving plate (29) facing the outer peripheral portion of the plate (24) is provided, and a number of vertically extending guide posts (34) are provided on the spring receiving plate (29) and the outer peripheral portion of the support plate (24). A large number of metal disc springs (37) are fitted to each guide post (34) by turning them up and down, and the pressing force of the upper and lower dies (43, 30) by the disc springs (37) is provided. The closed forging apparatus according to claim 1 or 2, wherein the pressure contact force required for closed forging. 4. An intermediate spring receiver (38) is fitted to an intermediate portion of each guide post (34) so as to be vertically slidable, and one end of each guide post (34) and the intermediate spring receiver (38).
Between the guide post (34) and the intermediate spring receiver (38). (37
a) a metal coil spring (37) having a smaller elastic force than that of (a).
4. A closed forging device according to claim 3, further comprising a restricting body (b) for preventing overcompression of the coil spring (37b).