JPH0716727B2 - Press molding equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a press forming apparatus, and more particularly to a press forming apparatus suitable for press forming a conical tapered surface of a workpiece.

(Prior Art) Conventionally, in this type of press forming apparatus, when press-forming a conical taper surface on a work piece placed on a work table, the taper surface of the work piece is to be press-formed. It is usually performed by pressing the punch.

(Problems to be Solved by the Invention) In such a configuration, when a conical taper surface having a small surface accuracy and a high roundness suitable for a seal or the like is to be obtained by press molding, high precision press molding is required. Equipment is required. However, in terms of the original function of the press-molding apparatus, it is not a good idea to increase the precision of a portion that does not have the necessity of increasing the precision because it is expensive. Even with such an expensive press molding apparatus, there is a strict discrepancy in the cores, and there is a limit in increasing the roundness.

Therefore, in order to cope with such a situation, the present invention aims to sufficiently enhance the press forming accuracy of a conical tapered surface of a workpiece in a press forming apparatus without unnecessarily increasing the press forming accuracy. Is what you are trying to do.

(Means for Solving the Problem) In solving the problem, the structure of the present invention is supported by a stationary member above a processing table on which a workpiece is placed and hangs vertically toward the workpiece. A pressurizing cylinder having a drive shaft, a shaft-shaped tilting member which is connected to the drive shaft so as to be tiltable in the lateral direction and hangs down, and a lower portion of the tilting member is formed with a space immediately below the lid to cover the lid. A tubular casing coaxially fitted and fixed to the tilting member from below, a punch housed in the cavity so as to be movable laterally relative to a lower portion of the tilting member, and a punch housed in the cavity. An elastic member for urging the punch upward is provided, and a pressing rod of the punch is hung in a central hole of a bottom wall of the casing so that a tip cone portion thereof can face the workpiece. It was decided to let it fit loosely in.

(Operation) With the above configuration of the present invention, when the pressurizing cylinder moves its drive shaft downward, the casing moves downward together with the tilting member. Then, when a part of the lower end surface of the casing comes into contact with the upper surface of the workpiece, the casing tilts together with the tilting member to bring the entire lower end surface into contact with the upper surface of the workpiece. After that, when the tilting member further moves downward, the punch moves downward against the elastic member and partially abuts the work portion of the work piece at its tip conical portion, and then the lateral While moving in the direction, the tip conical portion is brought into contact with the entire circumference of the processed portion to press-form the tapered surface.

(Effect of the Invention) With such an action, the tapered surface of the processed portion of the workpiece is pressure-molded as a highly accurate tapered surface similar to the tip conical portion of the punch. In such a case, the punch is held in a floating state in the casing by the elastic member, and the punch responds to the tilting of the tilting member when the workpiece and the upper surface of the casing are partially brought into contact with each other. Since the tip conical portion is moved in the lateral direction with the tilting of the casing so that the tip conical portion is made to follow the portion to be processed, the tip conical portion of the punch does not need to be particularly improved in accuracy of this type of press forming apparatus. It is possible to achieve high-accuracy molding of the tapered surface of the processed portion while achieving high-precision centering between the portion and the processed portion of the workpiece.

(Embodiment) An embodiment of the present invention will be described below with reference to the drawings.
The figure shows an example of a press molding apparatus according to the present invention.
This press-molding apparatus is equipped with a processing table 10, on which an L-shaped base body 20 is erected on its leg parts 20a and its head part 20b is shown in FIG. It extends horizontally toward the front of the paper. A cylindrical tubular body 20 is provided in a through hole portion 21 vertically formed in the central portion of the head portion 20b of the base body 20.
c is coaxially fitted in the cylindrical portion 22, and the annular flange portion 23 of the cylindrical body 20c is seated on the upper end of the through hole portion 21.

The inverted L-shaped frame body 30 has both legs 30a and 30b symmetrically erected on the head portion 20b of the base body 20 as shown in FIG. The frame body 30 is assembled on the base body 20 by fastening, and a through hole 33 is formed coaxially with the tubular body 20c at the center of the horizontal upper wall 30c of the frame body 30.
The cylindrical pressure cylinder 40 is mounted on the upper wall 30c of the frame body 30 coaxially with the through hole 33, and the annular flange portion 41 of the pressure cylinder 40 is placed on the upper wall 30c of the frame body 30. Is fastened by screws 42, 43. The pressurizing cylinder 40 has a drive shaft 44, and the drive shaft 44 hangs coaxially in the frame 30 through a through hole 33. The pressurizing cylinder 40 vertically moves the drive shaft 44 in accordance with the operation thereof.

The coupling 50 has a stepped conical shape, and the large diameter portion 51 of the coupling 50 has a female screw hole portion 51a formed concentrically at the upper end portion thereof, together with a nut 51b, a driving shaft of the pressure cylinder 40. The small diameter portion 52 and the middle diameter portion 53 are coaxially hung so as to be fastened together with the male screw portion 44a of 44. Further, the lower end surface 53a of the middle diameter portion 53 is formed in a spherical shape. The rod 60 is connected to the medium diameter portion 53 of the coupling 50 by an annular large diameter portion 60a formed coaxially at the upper end thereof, as shown in FIG. 1, and the small diameter portion 60b of the rod 60 is It hangs down through the cylinder 20c. In such a case, the coupling 50 has a small diameter portion 52.
Is loosely fitted in a through hole 61 formed coaxially at the center of the upper wall of the large diameter portion 60a of the rod 60, and the middle diameter portion 53 is
60a is loosely fitted and connected. Also the coupling 5
0 The axial length of the medium diameter portion 53 is shorter than the distance between the axial upper and lower end faces in the large diameter portion 60a, and the large diameter portion of the rod 60
The tilting in the radial direction based on 60a is sufficiently allowed. Further, the axial length of the small diameter portion 52 is made larger than the plate thickness of the upper wall of the large diameter portion 60a.

A female screw hole portion 62 is coaxially formed in the lower portion of the small diameter portion 60b of the rod 60, and the rod 70 is screwed from below into the female screw hole portion 62 at its tip male screw portion 71. There is. The cylindrical tubular body 80 is coaxially fitted to the small diameter portion 60b of the rod 60 from the outside in the tubular body 20c.
The large-diameter hole portion 81 of the rod 60 has a lower portion of the small-diameter portion 60b of the rod 60, which is relatively rotatable in the circumferential direction and is relatively movable in the axial direction, through a direct acting ball bearing 90 press-fitted coaxially with the inner peripheral surface thereof. On the other hand, the small-diameter hole portion 82 of the cylindrical body 80 faces the upper portion of the small-diameter portion 60b of the rod 62 at the inner peripheral surface thereof with an annular gap. Further, the outer diameter of the tubular body 80 is set smaller than the inner diameter of the tubular body 20c by a predetermined length to allow the rod 60 to tilt.

Between the upper end surface of the tubular body 80 and the annular lower surface of the large diameter portion 60a of the rod 60, the coil spring 100 is provided, and the small diameter portion 60b of the rod 60 is provided.
The coil spring 100 has an annular inner end portion 83a of an annular flange 83 formed at the lower end of the tubular body 80, which is abutted on the flange portion 72 of the rod 70. I am in contact. The stepped cylindrical casing 110 has a flange portion 72 and a lower end portion 73 of the rod 70 at the large diameter portion 110a.
Is mounted on the flange 83 of the tubular body 80 coaxially from below by fastening each bolt 111, and the punch 120 is provided in the casing 110 with its flange portion 120a.
Is loosely fitted into the remaining space in the large diameter portion 110 substantially coaxially with the rod 70, and the boss portion 120b is fitted to the small diameter portion 110 of the casing 110.
The rod 120c is loosely fitted into the b substantially coaxially, and the rod 120c is inserted into the through hole 112 formed in the center of the lower wall of the small diameter portion 110b and accommodated therein. However, the inner diameter of the through hole 112 is set to be larger than the outer diameter of the rod 120c by a predetermined length so as to secure a sufficient amount of relative movement of the rod 120c in the radial direction with respect to the small diameter portion 110b.

Flange portion 120a of punch 120 and flange portion 72 of rod 70
A thrust bearing 130 is loosely fitted to the lower end portion 73 of the rod 70 and is interposed therebetween. The thrust bearing 130 allows relative movement in the radial direction between the flange portions 120a and 72. is doing. Also, the flange portion 1 of the punch 120
Between the 20a and the bottom wall of the small-diameter portion 110b of the casing 110, a coil spring 140 is interposed in the small-diameter portion 110b by being substantially coaxially loosely fitted to the tubular portion 120b of the punch 120, The coil spring 140 biases the flange portion 120a upward, and at the same time, lower surface of the flange portion 120a and the large diameter portion 11a.
A predetermined gap h is provided between the upper surface of the annular step portion 0a. However, the spring constant of the coil spring 140 is made larger than that of the coil spring 100. The conical taper surface 11a of the stepped hole 11 formed by rough machining on the upper wall of the workpiece 10a on the machining table 10 is the rod 120c of the punch 120.
Corresponds to the surface press-molded by the conical portion 120d formed at the tip of the.

In the present embodiment configured as described above, the casing 11
The small diameter portion 110b of 0 and the rod 120c of the punch 120 are the workpiece 10
It shall be at the position shown in FIG. 2 with respect to the stepped hole 11 of a. In this state, if the pressurizing cylinder 40 moves the drive shaft 44 downward in response to its operation, the rod 60 and the tubular body 80 will move to the tubular body 20.
Both of them move downward in c, and the small-diameter portion 110b of the casing 110 abuts on the workpiece 10a at the lower right end in FIG. Therefore, the spring constant of the coil spring 100 is smaller than that of the coil spring 40, and an annular gap exists between the outer peripheral surface of the cylindrical body 80 and the inner peripheral surface of the cylindrical body 20c. Therefore, the tubular body 80 tilts in the tubular body 20c rightward in FIG. 1 with reference to the coupling 50 together with the rod 60. As a result, the small diameter portion 110b of the casing 110 is corrected so as to tilt so as to come into contact with the workpiece 10a over the entire lower end surface thereof.

After that, when the drive shaft 44 of the pressurizing cylinder 40 further moves downward against both coil springs 100 and 140, the rod 60 moves to the cylindrical body 80.
Move down along the linear motion ball bearing 90 and punch 120
Moves downward together with the thrust bearing 130, and the conical portion 120d of the rod 120c is stepped hole 11 as shown by a point P in FIG.
The lower end of the taper surface 11a is abutted. At this time, due to the contact between the conical portion 120d and the tapered surface 11a as described above, a pressing force S as shown in FIG. 3 is generated in a vector amount. Therefore, the radial component Sr of the pressing force S effectively acts on the movement of the conical portion 120d of the rod 120c to the left in the drawing in FIG.

Then, the punch 120 moves downward along the thrust bearing 130 according to the radial component Sr of the pressing force S while moving downward under the action of the pressurizing cylinder 40, and moves to the left in FIG. The portion 120d is brought into contact with the entire lower end portion of the tapered surface 11a as indicated by the two-dot chain line in FIG. After that, the drive shaft 44 of the pressurizing cylinder 40 is connected to both coil springs 100, 140.
If the punch 120 is further moved downward, the punch 120 press-forms the tapered surface 11a of the stepped hole 11 with the tapered surface 11b by the conical portion 120d as shown in FIG. At this time, the predetermined gap h is zero due to the compression of the spring 140.

As a result, the tapered surface 11b of the stepped hole 11 is formed as a highly accurate tapered surface similar to the conical portion 120d of the punch 120.
In such a case, the punch 120 is held in a floating state in the casing 110 by the coil spring 140, and when the casing 110 partially contacts the upper surface of the workpiece 10a, the punch 120 is tilted by the coil 60 and the coil spring 100. By moving the casing 110 along with the tilting of the casing 110 according to the compression of, the rod 120c is made to follow the stepped hole 11, so without particularly increasing the precision of this type of press forming apparatus, It is possible to achieve the centering between the rod 120c of the punch 120 and the stepped hole 11 of the workpiece 10a with high accuracy, and at the same time, to achieve the high precision molding of the tapered surface 11b. Further, since the spring constant of the coil spring 100 is small, the force required to cause the punch 120 to follow the workpiece 10a is a weak force (about 1/20) of the working force.

In carrying out the present invention, the rod 60 and the cylindrical body 80
Alternatively, the rotation may be restricted by a key, a detent screw, or the like.

Further, the coil springs 100 and 104 may be replaced with elastic rubber or leaf springs.

[Brief description of drawings]

FIG. 1 is a fragmentary front view showing an embodiment of the present invention, and FIGS. 2 to 4 are explanatory views showing an operating process of the present invention. Explanation of code 10 …… Processing table, 10a …… Workpiece, 11 …… Stepped hole, 20…
… Base, 30… Frame, 40… Pressure cylinder, 44… Drive shaft, 50… Coupling, 60, 70… Rod, 80… Cylindrical body, 110… Casing, 120… Punch , 120c …… rod, 120d …… cone part, 140 …… coil spring.

Claims (1)

[Claims] 1. A pressurizing cylinder having a drive shaft which is supported by a stationary member above a work table on which a work piece is placed and which hangs vertically toward the work piece, and a pressure cylinder transverse to the drive shaft. A shaft-shaped tilting member that is connected so as to be tiltable in the direction and hangs down,
A tubular casing coaxially fitted and fixed to the tilting member from below so as to cover the lower part of the tilting member by forming a space directly below the tilting member, and a lower part of the tilting member in the space. The punch rod is housed in the cavity so as to be relatively movable in the lateral direction, and the elastic member is housed in the cavity and biases the punch upward. A press forming apparatus adapted to be loosely fitted into a central hole of the bottom wall of the casing so as to face the work piece.