JP2016221539A - Deep hole forging processing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a deep hole forging processing device capable of executing efficient processing by shortening a processing time, by effectively restraining buckling of a projection pin.SOLUTION: A deep hole forging processing device 101 comprises a punch 11, a punch sleeve 12, a die 13 provided on the extrusion side of the punch 11 and a counter punch 15 fixed to the die 13. The punch 11 pushes out a raw material W1 backward by moving in the axial direction. The counter punch 15 bores-processes a deep hole 1 extending in the axial direction from a lower end surface 10 while pressing the lower end surface 10 of the raw material W1 when pushing out the raw material W1. The die 13 has a die hole 21 for forming a clearance between the raw material W1 pushed out by the punch 11 and itself. Before boring-processing, the punch sleeve 12 and the die 13 position and fix the raw material W1 to the counter punch 15. The die 13 allows deformation in the radial outer direction of the raw material W1 caused by the boring-processing.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a deep hole forging apparatus.

  Conventionally, as described in, for example, Patent Document 1, a forging technique is known in which a material made of a metal material is placed on a die, the material is pressed by a punch, and the material is molded into a predetermined shape. In such a forging process, when forming holes in the material, a counter punch as a protruding pin is provided on the die, the punch is lowered to extrude the material, and a hole corresponding to the shape of the counter punch is formed at a predetermined position of the material Like to do.

Japanese Patent Laid-Open No. 5-57392

  By the way, there is a case where it is desired to form a narrow and deep hole having a L / D ratio of 10 or more with respect to a material made of, for example, a stainless material used for a portion through which a high-pressure fluid flows. Here, L indicates the depth of the hole, and D indicates the diameter of the hole. When such a deep hole is formed, a large load acts on the outer surface of the counter punch when the material flows between the counter punch and the die during processing, and the counter punch is likely to buckle. Since there is a limit to the improvement of the buckling limit, for example, when forming a deep hole having an L / D ratio of 10 or more, it is necessary to perform multi-stage forging in multiple times, which is not efficient. There was a problem.

  Furthermore, when the counter punch has a small radial cross-sectional area relative to the cross-sectional area of the material, that is, when the cross-sectional reduction rate is small, for example, 10% or less, the load acting on the counter punch becomes larger, and the above problem further Become prominent.

  The present invention was created in view of the above points, and its purpose is to effectively reduce buckling of the projecting pin in deep hole forging, thereby reducing processing time and improving efficiency. An object of the present invention is to provide a deep hole forging device capable of processing.

  The deep hole forging device of the present invention includes a punch, a die, a fixing means, and an allowing means. The punch moves in the axial direction and pushes out the material. The die is provided on the extrusion side of the punch, and has a projecting pin that drills a deep hole extending in the axial direction from the end surface while pressing the end surface of the material when the material is extruded. The fixing means positions and fixes the material with respect to the protruding pin prior to the drilling process. The permissive means allows the material to be deformed in the radially outward direction due to the drilling process.

  When the material is extruded and the deep hole is formed by the protruding pin, the material flows along the outer surface of the protruding pin as the protruding pin is inserted into the material. At this time, usually, a strong frictional force is generated between the protruding pin and the material. However, in this configuration, since there is a permissive means that allows deformation of the material from the center to the outside, the frictional force between the protruding pin and the flowing material is reduced, and the load acting on the protruding pin is reduced. The buckling of the protruding pin can be suppressed as much as possible.

  Thus, for example, when forming a deep hole having an L / D ratio of 10 or more, it has been necessary to repeat a forging process a plurality of times. According to this configuration, a deep hole is formed in a single process. The processing time can be shortened and the processing can be performed efficiently.

It is sectional drawing which shows typically the deep hole forge processing apparatus by 1st Embodiment of this invention, and is a figure which shows the state before a drilling process. It is sectional drawing which shows the deep hole forge processing apparatus by 1st Embodiment of this invention typically, and is a figure which shows the state just before a drilling process start. The enlarged view which shows the broken-line part in FIG. It is sectional drawing which shows typically the deep hole forge processing apparatus by 1st Embodiment of this invention, and is a figure which shows the state at the time of drilling completion. It is sectional drawing which shows typically the deep hole forge processing apparatus by 2nd Embodiment of this invention, and is a figure which shows the state before a drilling process. The top view which shows a cam holder and a slide cam. It is sectional drawing which shows typically the deep hole forge processing apparatus by 2nd Embodiment of this invention, and is a figure which shows the state just before a drilling process start. It is sectional drawing which shows typically the deep hole forge processing apparatus by 2nd Embodiment of this invention, and is a figure which shows the state at the time of drilling completion. The figure which shows the urging | biasing force and flow force which arise with the downward stroke of a punch. The figure which shows the urging | biasing force and flow force which arise with the downward stroke of a punch by other embodiment.

Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings.
<First Embodiment>
[Constitution]
A deep hole forging device 101 according to a first embodiment of the present invention will be described with reference to FIGS. In this embodiment, a deep hole having an L / D ratio of about 10 is formed in a cylindrical material W1 made of stainless steel by forging. First, the configuration of the deep hole forging device 101 will be described. In the present specification, in the following cross-sectional views, the lines visible behind the cut surface are appropriately omitted.

  As shown in FIGS. 1, 2, and 4, the deep hole forging device 101 of this embodiment includes a punch 11, a punch sleeve 12, a die 13, a slide punch guide 14, and a counter punch 15. And a holder 16 and the like.

  The punch sleeve 12 is a cylindrical member, and the punch 11 is inserted therein. The die 13 constituting a part of the lower die is positioned on the side of the punch 11 where the punch 11 is pushed out, and a die hole 21 is formed therein. The extrusion side of the punch 11 is “rear”, and is “lower” in the present embodiment. Further, the side opposite to the extrusion side is “front”, and in this embodiment is “upper side”.

  The die hole 21 is stepped and has a large-diameter hole portion 22 through which the punch sleeve 12 is inserted and a small-diameter hole portion 23 through which the slide punch guide 14 is inserted. The small-diameter hole portion 23 is located on the extrusion side from the large-diameter hole portion 22, and, as shown in FIG. 3, when the material W1 extruded by the punch 11 is inserted, between the outer periphery of the material W1. The gap C is formed. Here, the punch sleeve 12 and the die 13 correspond to “fixing means” described in the claims. The die 13 corresponds to “allowing means” described in the claims.

  The slide punch guide 14 is externally attached to the counter punch 15, and supports the counter punch 15 perpendicularly to the material W1. The slide punch guide 14 is slidably arranged in the vertical direction in the small-diameter hole portion 23 via a spring (not shown).

  The counter punch 15 is a pin member whose tip is round and has a gently curved surface, and is fixed in the small-diameter hole 23 with its base end held by the holder 16. The shape of the counter punch 15 is transferred as the shape of the deep hole 1 (see FIG. 4) formed in the material W1. At the center of the lower end surface 10 of the material W1, a hole 24 into which the tip of the counter punch 15 is inserted when centering with the counter punch 15 is formed to be concave in the axial direction. The hole 24 is formed in the material W1 in the pre-process of deep hole forging. In addition, the ratio of the radial cross-sectional area of the counter punch 15 to the radial cross-sectional area of the material W1, that is, the cross-sectional reduction rate is 10% or less.

[Action]
Next, a deep hole forging method using the deep hole forging apparatus 101 will be described. With the punch 11 and the punch sleeve 12 raised, the punch sleeve 12 is first lowered to the large-diameter hole portion 22 of the die hole 21. Next, the material W <b> 1 is put into the punch sleeve 12. As shown in FIG. 1, the lower end surface 10 of the material W <b> 1 contacts the upper end surface of the slide punch guide 14. Next, while the punch 11 is guided by the punch sleeve 12, the punch 11 is lowered until it abuts on the upper end surface of the material W1. At this time, the outer periphery and bottom surface of the punch sleeve 12 and the large-diameter hole portion 22 of the die 13 are fitted. Further, the inner periphery of the punch sleeve 12 and the material W1 are fitted. Thereby, the coaxiality of the die 13 and the punch sleeve 12 is ensured. As a result, the coaxiality of the material W1 with respect to the counter punch 15 is ensured.

  Next, the punch 11 is slightly lowered and the tip of the counter punch 15 is brought into contact with the bottom of the centering hole 24 formed in the material W1 as shown in FIG. This is the state immediately before the start of drilling, and the material W1 is not moved by the die 13 and the punch sleeve 12, and is positioned and fixed straight with respect to the counter punch 15.

  Next, the punch 11 is further lowered, and the deep hole 1 is formed in the material W1 as shown in FIG. As the punch 11 descends, the lower end surface 10 of the material W1 is pressed with a strong force by the counter punch 15, and the deep hole 1 extending in the axial direction from the lower end surface 10 is gradually formed. At this time, the outer diameter of the material W1 is unconstrained by the gap C (see FIG. 3) with the die hole 21 (small-diameter hole portion 23), and the material W1 can flow in the radially outward direction. When the counter punch 15 is inserted, the material at the inserted portion is pushed backward along the side surface of the counter punch 15. At this time, a strong frictional force usually acts between the counter punch 15 and the material W1, but in this embodiment, the material W1 can flow in the radially outward direction due to the gap C, and thus the frictional force is reduced. The

[effect]
According to the present embodiment, by making the outer diameter of the material W1 during drilling unconstrained, the frictional force between the material W1 and the counter punch 15 is reduced, and the material can be pushed backward with less resistance. it can. And the buckling of the counter punch 15 is suppressed as much as possible by reducing the surface pressure generated in the counter punch 15. Thereby, damage to the counter punch 15 can be reduced and the life of the counter punch 15 can be extended.

  In addition, when forming a deep hole having an L / D ratio of 10 or more, for example, it has been necessary to perform multi-stage forging in a plurality of times, but according to the present embodiment, the process is performed once. Deep holes can be formed, processing time is shortened, and processing can be performed efficiently.

  Further, when the cross-section reduction rate is small, such as 10% or less, the load acting on the counter punch 15 tends to increase. However, according to the present embodiment, even if the cross-section reduction rate is 10% or less, the counter punch 15 Can be effectively suppressed.

  In addition, there is a method of forming a deep hole by cutting when forming a deep hole, but it is difficult to process the shape of the stop portion corresponding to the bottom of the hole in cutting, and it takes time to perform accurate hole processing. There is. In that respect, in the forging process according to the present embodiment, the tip shape of the counter punch 15 can be transferred, so that the process is easy. Moreover, in the forging process, work hardening of the raw material W1 is obtained, and in view of the recent high pressure situation, the deep hole 1 can be formed while giving strength to the raw material W1 by the forging process. Can be formed.

Second Embodiment
[Constitution]
Next, a deep hole forging device 102 according to a second embodiment of the present invention will be described with reference to FIGS. The material W <b> 2 in the present embodiment is a stainless steel material, and is a cylindrical member with a flange having a cylindrical portion 31 and a flange portion 32. A deep hole having an L / D ratio of about 10 is formed in this material W2 by forging. First, the configuration of the deep hole forging device 102 will be described.

  As shown in FIGS. 5, 7, and 8, the deep hole forging device 102 of the present embodiment includes a punch 11, a die 33, a cam holder 34, a slide cam 35, and a slide punch guide 14. The counter punch 15, the holder 16, and the gas cushion 36 are provided.

  The die 33 constituting a part of the lower mold has a cylindrical shape having an opening at one end, and a cam holder 34, a slide cam 35, a slide punch guide 14, a counter punch 15, a holder 16, and a gas cushion 36 are contained therein. Each member is accommodated. Note that the punch 11, counter punch 15, holder 16, and slide punch guide 14 have substantially the same structure as that of the first embodiment, and therefore, the same reference numerals as those of the first embodiment are used and description thereof is omitted.

  The cam holder 34 is a thick cylindrical member, and is disposed in the die 33 so as to be slidable in the pushing direction. A hole 37 into which the slide punch guide 14 is inserted is formed at the center of the cam holder 34. The pushing side of the cam holder 34 is connected to a gas cushion 36. The gas cushion 36 generates a cushioning force Fc opposite to the pushing direction, that is, forward.

  The cam holder 34 receives a forward pressing force from the gas cushion 36 as the punch 11 is lowered. As shown in FIG. 6, a plurality of (for example, six) slits 38 extending in the axial direction are formed at equal intervals in the circumferential direction on the punch 11 side (the upper side in the present embodiment) of the cam holder 34. The lower end of the slit 38 is formed as a tapered surface 39 whose height increases in the radially outward direction.

  The slide cam 35 is a thin plate member whose cross-sectional shape is a pentagonal shape, and is formed as an inclined surface 41 whose one side has the same inclination as the tapered surface 39 of the cam holder 34. The slide cam 35 is arranged one by one in each slit 38 with one side extending straight in the vertical direction positioned on the inner diameter side of the cam holder 34 and the inclined surface 41 facing the tapered surface 39 of the cam holder 34.

  Then, as shown in FIG. 7, an urging force Fe inward in the radial direction acts on the slide cam 35 through the tapered surface 39 and the inclined surface 41 by the transmission of the upward cushion force Fc by the gas cushion 36. It is like that. The urging force Fe according to the lowered state of the punch 11 acts, so that the slide cam 35 can move in the radial direction within the slit 38. The slide punch guide 14 is supported by an inner peripheral surface in which no slit 38 is formed in the hole 37 of the cam holder 34. Here, the slide cam 35 corresponds to “fixing means” and “allowing means” described in the claims.

[Action]
Next, a deep hole forging method by the deep hole forging device 102 will be described. The material W2 is put on the slide punch guide 14 with the punch 11 raised. Next, when the punch 11 is lowered, the punch 11 comes into contact with the upper end surface of the material W2 as shown in FIG. Further, as the punch 11 descends, the lower end surface of the flange portion 32 of the material W2 comes into contact with the upper end surface of the slide cam 35 as shown in FIG. At this time, the slide cam 35 receives the urging force Fe, slides slightly inward in the radial direction so as to slide on the tapered surface 39, and grips the outer peripheral portion of the material W2. Accordingly, the material W2 is positioned and fixed, and the coaxiality of the material W2 with respect to the counter punch 15 is ensured.

  Next, the punch 11 is further lowered, and a deep hole 2 is formed in the material W2 as shown in FIG. As the punch 11 descends, the cam holder 34 slides downward. Then, the lower end surface 20 of the material W2 is pressed with a strong force by the counter punch 15, and the deep holes 2 extending in the axial direction from the lower end surface 20 are gradually formed.

  Here, FIG. 9 is a diagram showing the urging force Fe and the flow force Fm generated along with the lowering stroke of the punch 11, and shows a state after the start of drilling. The fluid force Fm is a force that tends to deform in the outer diameter direction when the material W2 is pressed in the axial direction. In the radial direction of the material W2, a flow force Fm caused by the material W2 and an urging force Fe caused by the slide cam 35 act during processing. As shown in FIG. 9, the flow force Fm increases rapidly after the start of machining, and the rising gradient becomes gentle as the drilling process proceeds to some extent. On the other hand, the urging force Fe is proportional to the cushioning force Fc by the gas cushion 36, that is, linearly increases in proportion to the stroke.

  At the time of starting the drilling process and immediately after starting the drilling process, the urging force Fe is larger than the flow force Fm, and the material W2 is firmly held radially inward by the urging force Fe. When the stroke of the punch 11 increases and the counter punch 15 is gradually inserted into the material W2, the fluid force Fm exceeds the biasing force Fe at an early stage when the stroke becomes t. Then, as shown in FIG. 8, the slide cam 35 moves by sliding on the tapered surface 39 in the radially outward direction so as to follow the flow of the material W2. That is, when the flow force Fm increases to some extent, the material flow in the radially outward direction of the material W2 is permitted by the movement of the slide cam 35.

  Immediately after the start of the drilling process, there is room for the material W2 to flow backward along the outer surface of the counter punch 15, and therefore it is preferable that the biasing force Fe is higher from the viewpoint of fixing the material W2. However, as the drilling process proceeds, the material becomes difficult to flow, and at that time, it is important to allow the flow of the material W2 in the outer diameter direction.

  As described above, the slide cam 35 functions as a fixing means for fixing the material W2 and an allowance means for allowing deformation of the material W2 according to the balance between the urging force Fe and the fluid force Fm. That is, when the urging force Fe is larger than the flow force Fm, the slide cam 35 functions as a fixing unit that fixes the material W2 by the urging force Fe. When the fluid force Fm is larger than the urging force Fe, the slide cam 35 functions as a permitting unit that allows the material force W2 to be deformed in the radially outward direction by the fluid force Fm.

  According to the present embodiment, the same effect as that of the first embodiment can be obtained, and the deep hole 2 can be efficiently formed by forging the material W2 having a flanged cylindrical shape. Further, since a plurality of the slide cams 35 are provided radially outside the material W2, it is possible to suitably allow deformation of the material over the outer periphery of the material W2.

<Other embodiments>
In the first embodiment, the gap C is provided between the die 13 and the material W1 at the machining start position. However, the gap C is not necessarily formed at the machining start position. Drilling may be started, and a gap C may be formed between the die 13 and the material W1 at a position where the punch 11 is slightly lowered. The point is that the material W1 can be allowed to flow in the radial direction by the gap at the stage where there is no room for the material W1 to be pushed backward along the outer surface of the counter punch 15.

  In the second embodiment, six slide cams 35 are provided. However, a plurality of slide cams 35 may be provided, such as a single piece or other three pieces. The slide punch guide 14 is held on the inner peripheral surface in which the slit 38 is not formed in the hole 37 of the cam holder 34. If the slide punch guide 14 can be appropriately held, six or more are provided. Multiple sheets may be used.

  In the second embodiment, as in the first embodiment, the centering hole 24 may be formed in the material W2 in the previous step.

  In the second embodiment, the slide cam 35 is pressed in the axial direction by the flange portion 32 of the material W2. However, for example, a flat cam pressing member may be provided as a separate member.

  In the second embodiment, the cushion force Fc by the gas cushion 36 is used. However, other configurations may be used as long as the slide cam 35 can be slid radially outward with the deformation of the material W2. For example, the radially outward direction of the slide member is connected to a spring, and the spring is biased radially inward with a predetermined force. When the material W2 is deformed, the slide member may follow the deformation of the material W2 and move outward in the radial direction.

  In the second embodiment, a hydraulic cushion may be provided instead of the gas cushion 36, and the urging force Fe may be constant as shown in FIG.

  In each of the above embodiments, both the materials W1 and W2 are cylindrical members, but the outer shape of the materials can be variously modified. For example, a pipe-shaped member that is long in the axial direction or a polygonal cross section orthogonal to the axial direction is polygonal. It may be a member having a shape. In the case of a member having a polygonal shape, the “radially outward direction” described in the claims refers to an outside in a plane orthogonal to the axial direction, for example, from the central axis of the material that coincides with the pushing direction of the punch 11. It can be interpreted as meaning direction.

  The present invention is not limited to the embodiments described above, and can be implemented in various forms without departing from the spirit of the invention.

1, 2 ... Deep hole 10 ... Lower end face (end face)
11: Punch 12: Punch sleeve (fixing means)
13 ... Die (fixing means, permitting means)
15 ・ ・ ・ Counter punch (protruding pin)
20 ... Lower end surface (end surface)
21 ・ ・ ・ Die hole 33 ・ ・ ・ Die 35 ・ ・ ・ Slide cam (sliding member, fixing means, allowing means)
36 ・ ・ ・ Gas cushion (cushion member)
101, 102 ... Forging deep hole processing device Fc ... Cushion force Fe ... Energizing force Fm ... Fluid force

Claims (5)

A punch (11) that moves in the axial direction and extrudes the material (W1, W2);
Protrusions provided on the extrusion side of the punch for punching deep holes (1, 2) extending in the axial direction from the end surfaces while pressing the end surfaces (10, 20) of the materials when the materials are extruded. A die (13, 33) having a pin (15);
Prior to the drilling process, fixing means (12, 13, 35) for positioning and fixing the material with respect to the protruding pin;
Allowance means (13, 35) for allowing deformation of the material in the radially outward direction accompanying the drilling process;
A deep hole forging device characterized by comprising:   The die (13) has a die hole (21) that forms a gap (C) between the die (13) and the material (W1) pushed out by the punch, and also serves as the allowance means. The deep hole forging device according to 1. The allowing means is
Provided on the radially outer side of the material (W2), the diameter of the material is allowed to be deformed in the radially outward direction by the flow force (Fm) that deforms the material in the radially outward direction during the drilling process. The deep hole forging device according to claim 1, wherein the deep hole forging device is a slide member (35) movable outward. A cushion member (36) for generating a cushioning force (Fc) in the direction opposite to the pushing direction by the punch,
Depending on the balance between the urging force (Fe) generated by transmission of the cushion force and urging the slide member in the radially inward direction, and the fluid force,
When the biasing force is larger than the fluid force, the slide member functions as the fixing means for fixing the material by the biasing force,
The said slide member functions as the said permissible means which accept | permits the deformation | transformation to the radial direction of the said raw material by the said fluid force when the said fluid force is larger than the said urging | biasing force. Deep hole forging machine.   5. The deep hole forging device according to claim 3, wherein a plurality of the slide members are radially provided outside the raw material in the radial direction.

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