JP3176271B2 - Initial pressure loading device for press dies - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an initial pressure loading device for a press die, which applies an initial pressure to an elastic body such as a coil spring or rubber incorporated in the press die in advance.

[0002]

2. Description of the Related Art Conventionally, as an initial pressure load device for a press die, for example, a device shown in FIGS. 8 to 10 is well known as a conventional example. As an initial pressure load device in this conventional example, an upper die 1 attached to an upper ram of a press device is used.
An elastic body 3 such as a coil spring or rubber built in for the purpose of holding down and fixing the workpiece is used, and its arrangement and fixing means are, as shown in FIG. A pressing plate 2 for a workpiece disposed below the upper die 1, an elastic body 3 such as a coil spring interposed between the pressing plate 2 and the upper die 1, A stepped bolt 4 whose base end is supported by the presser plate 2, and the elastic body 3 is disposed on the upper surface of the presser plate 2 with a free length, and a short cylindrical spring guide is provided therein. The stepped bolt 4 is fastened and fixed via a bush 5.

When an initial pressure is applied in advance for the purpose of increasing the pressing force of the workpiece, as shown in FIG. 9, a coil spring or the like is provided between the upper die 1 and the pressing plate 2. In addition to the elastic body 3, a stopper bolt 8 for applying initial pressure to which a screw is applied is interposed, and the screw head 9 is inserted into the elastic body 3 as shown in FIG.
And the interfering part can be escaped by the escape hole 11 or the like.

[0004]

However, in the above-mentioned conventional initial pressure loading means, a relief hole 11 and a space for screw operation are required in the pressing plate 2 of the workpiece. In bending, it was difficult to secure the space.

Also, a method of inserting the screw rod 9 into the elastic body 3 by tightening the head with a double nut 10 and releasing the interfering part with the escape hole 11 or the like can be used.
In addition to the time required to adjust the height of the holes to the same value, extra man-hours were required, such as machining the relief holes.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and can easily and surely provide an elastic body such as a coil spring without using a conventionally used spring guide bush, a relief hole, and a space for screw operation. It is an object of the present invention to provide an initial pressure loading device for a press die capable of applying an initial pressure in advance.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned conventional problems and to achieve the intended object, the constitution of the present invention comprises an upper mold having a predetermined shape, and an upper mold having a predetermined shape. A holding plate for a workpiece disposed at a lower position, an elastic body made of a coil spring or rubber or the like interposed between the holding plate and the upper die, and a base end side supported by the holding plate. with the a fastening member of the stepped bolts, and the elastic body, the first pressure load for press die formed by freely held displace the fastening member via a flanged bush free end In the device ,
The flanged bush projects outward from the outer peripheral surface of the upper end
An outer flange for pressing and supporting the upper end surface of the elastic body,
At least the fastening member protrudes inward from the inner peripheral surface of the end.
And an inner collar for slidably retaining the large diameter part of
A cylindrical body provided with the elastic body at the lower end surface of the outer flange.
Fitted in the center hole of the elastic body to be locked on the upper end surface
In this state, the fastening member supported and retained by the inner collar is
There is an initial pressure load device for a press die formed by screwing only the lower end side to the holding plate .

[0008]

Further, the outer flange may have a gradient of 3 to 10 degrees on the contact surface side with the elastic body.

[0010] In the initial pressure loading device for a press die according to the present invention, the bush with a flange is formed as follows.
Pressing and supporting the upper end surface of the elastic body by projecting outward from the surface
And an outer flange for
At least, it is possible to slidably support the large diameter portion of the fastening member.
And a cylindrical body having an inner flange for holding the outer flange.
The elastic member is locked at the lower end surface to the upper end surface of the elastic body.
With the inner collar fitted in the center hole of the body,
Only the lower end side of the supported fastening member is screwed to the holding plate.
With this configuration, the elastic body moves from the free length state.
Initial pressure is applied as a single unit.
Can be deformed up to the amount of deflection that can be obtained.
The initial pressure can be easily applied .

[0011]

In addition, a plurality of elastic members are incorporated in order to uniformly tighten the flanged bush from above through a fastening member such as a hexagon socket head bolt machined to a predetermined size by machining. In this case, there is no variation in height.

Further, if the outer flange is provided with a gradient of 3 to 10 degrees on the contact surface side with the elastic body, a centering effect of the gradient of the flange surface is produced, and the inner peripheral surface of the elastic body is There is almost no contact with the outer peripheral surface of the flanged bush, and the durability of the elastic body can be significantly improved.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a first embodiment of an initial pressure load device for a press die according to the present invention will be described with reference to FIGS. A in FIG. 1 is an initial pressure load device for a press die according to the present invention, and the initial pressure load device A includes an upper die 1 having a predetermined shape as shown in an enlarged view in FIG. A holding plate 2 for a workpiece disposed below the upper mold 1;
An elastic body 3 interposed between the holding plate 2 and the upper mold 1
And a fastening member 4 whose upper end is slidably held by the elastic body 3 and whose lower end is connected and supported by the pressing plate 2.

The elastic member 3 is made of a coil spring, rubber, or the like, and supports the fastening member 4 at its release end via a flanged bush 5 described later so as to be freely displaceable.

Further, a stepped bolt having an enlarged head is used as the fastening member 4, but a stepped bolt with a hexagonal hole machined to a predetermined size by machining is preferably used. It is preferred to use.

In other words, as shown in FIG. 2, the fastening member 4 is screwed onto the holding plate 2 so that the large-diameter portion 4a is engaged with an inner flange 5b of a flanged bush 5 described later. The hexagonal wrench is inserted into a hexagonal hole (not shown) formed in the top end surface of the large diameter portion 4a, and can be detachably fastened and screwed by rotating in a predetermined direction. .

On the other hand, the flanged bush 5 has an outer flange 5a for pressing and supporting the upper end surface (free end surface) of the elastic body 3.
And a cylindrical body having an upper end opening provided with at least an inner flange 5b for locking the large diameter portion 4a of the fastening member 4, and the fastening member is provided through an opening 5c formed in the lower end surface thereof. 4
Is slidably held.

The initial pressure loading device for a press die according to the present invention, which is configured as described above, comprises a bush with a flange 5 at the upper end of an elastic body 3 interposed between the upper die 1 and the holding plate 2. And the large diameter portion 4a of the fastening member 4 is slidably engaged, so that the upper end of the elastic body 3 always contacts the lower surface of the outer flange 5a of the flanged bush 5, A bending amount corresponding to a desired initial pressure can be applied to the free length of the elastic body 3, and a pressing force is applied from the upper surface of the outer flange 5a in this state, and as shown in FIG. Since the body 3 is compressed, there is no need for a spring guide bush, a relief hole, and a space for screw operation, which were conventionally used.
The initial pressure can be applied to the elastic body 3 simply and reliably.

Next, a second embodiment of an initial pressure load device for a press die according to the present invention will be described with reference to FIGS. To facilitate understanding, the same parts as those in the first embodiment are denoted by the same reference numerals, and only the parts having different configurations will be described with new numbers.

FIG. 4 is a cross-sectional view showing a state where an initial pressure is applied to the elastic body 6 via the flanged bush 5.
For example, a urethane spring or elastic rubber is used in place of the coil spring used in the first embodiment.

In particular, the urethane spring is made of a polyester cast urethane elastomer having excellent heat resistance, excellent in repeated compression characteristics, and having high rebound resilience, impact resistance, weather resistance, and load resistance. Combined with its excellent properties, it is most suitable as an elastic body for a press die.

The elastic body 6 is disposed between the upper mold 1 and the holding plate 2 as in the first embodiment, but has a through hole formed in the axial direction. The flanged bush 5 is held coaxially through the hole 6a.

In other words, the flanged bush 5 is fitted into the through hole 6a so that the lower surface of the outer flange 5a contacts the upper end surface of the elastic body 6, and is different from the first embodiment. Similarly, the large-diameter portion 4a of the fastening member 4 is locked to the inner flange 5b (see FIG. 4).

Therefore, the initial pressure loading device for a press die according to the present invention, which is configured as described above, can previously apply a bending amount corresponding to a desired initial pressure to the free length of the elastic body 6. At the same time, a pressing force is applied from the upper surface of the outer flange 5a from this state, and the elastic body 6 is compressed downward (see FIG. 5). The initial pressure can be applied to the elastic body 6 simply and reliably without requiring the holding plate 2 at all.

Next, a third embodiment of an initial pressure load device for a press die according to the present invention will be described with reference to FIGS. For easy understanding, the same parts as those in the above-described first and second embodiments are denoted by the same reference numerals, and only the parts having different configurations will be described with new numbers.

FIG. 6 is a sectional view showing a state in which an initial pressure is applied to the rubber-like elastic body 6. The upper end of the elastic body 6 has a lower surface of the outer flange 7 a, that is, a contact surface side with the elastic body 6. An initial pressure is applied to the elastic body 6 through a flanged bush 7 having a gradient of 5 degrees.

The angle of the outer flange 7a produces a centering effect of the gradient of the flange surface, so that the inner peripheral surface of the elastic body 6 and the outer peripheral surface of the flanged bush 7 hardly come into contact with each other. The durability of the body 6 is remarkably improved, and the service life can be obtained about twice as long as the conventional spring guide bush.

It should be noted that the present invention is not limited to these embodiments, but can be freely changed in design within the scope of the present invention, and the present invention covers all of them. For example, in the present embodiment, the elastic bodies 3 and 6 are described as being set up substantially vertically, but the present invention is not limited to this, and the vertical movement of the press is converted into horizontal movement using the inclination angle. When a cam mechanism or the like is used, the elastic members 3 and 6 are also arranged substantially horizontally, and the elastic members 3 and 6 themselves are used with a free length. It is preferable to apply an initial pressure of about 5 to 8% of the repellent length.

The "press mold" referred to in the present specification is not limited to the cam cut mold shown in this embodiment (FIG. 1), but may be a flange mold, a cam piercing mold, or a blanking mold. It is needless to say that the initial pressure loading device of the present invention can be mounted and applied to all of these press dies such as a draw die, a draw die and the like.

[0031]

According to the initial pressure load device for a press die according to the present invention configured as described above, the flanged bush is
Overhang from the outer peripheral surface of the upper end to the upper end surface of the elastic body
Outer flange for pressure support and inward from inner peripheral surface at lower end
And slidably remove at least the large diameter portion of the fastening member.
It consists of a cylindrical body with an inner collar for supporting
The lower end of the outer collar is to be locked to the upper end of the elastic body.
In a state fitted in the center hole of the elastic body,
Only the lower end side of the fastening member supported and prevented from falling off is
The elastic body has a free length
Initial pressure is applied as a single unit from the state, and
Since it can be deformed up to the amount of deflection that gives the repulsion reaction force,
In other words, the initial pressure can be easily applied to the elastic body.
Is greater than the desired initial pressure for the free length of the elastic body.
Not only can be loaded up to the amount of deflection, but also
Easy and reliable without the need for holes or screw operation space
Apply an initial pressure to an elastic body such as a coil spring in advance.
Can provide an initial pressure loading device for press dies
You. In addition, the flanged bush is not
Through fastening members such as stepped bolts machined to a certain size
Can be tightened uniformly from above.
Even when incorporated, variations in height may occur
Absent.

[0032]

Further, if the outer flange is provided with a gradient of 3 to 10 degrees on the contact surface side with the elastic body, a centering effect of the gradient of the flange surface occurs, so that the inner peripheral surface of the elastic body and the flange are formed. There was almost no contact with the outer peripheral surface of the attached bush, the durability of the elastic body was remarkably improved, and a service life approximately twice as long as that obtained when a conventional spring guide bush was used was obtained.

As described above, according to the present invention, in particular, the contact between the spring and the spring guide bush can be avoided.
In addition to being able to apply initial pressure with the spring alone, eliminating the need for machining relief holes in other members such as the spring mounting plate, it has tremendous effects.In addition, the simple configuration is suitable for mass production and the price is low. Can be supplied to consumers as
Implementing the invention has tremendous practical value.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a press die to which an initial pressure load device according to the present invention is assembled.

FIG. 2 is an explanatory view of a main part showing a first embodiment of an initial pressure load device according to the present invention.

FIG. 3 is an explanatory view of a main part showing a lower limit position of the initial pressure load device.

FIG. 4 is an explanatory view showing a main part of a second embodiment of an initial pressure load device according to the present invention.

FIG. 5 is an explanatory view of a main part showing a lower limit position of the initial pressure load device.

FIG. 6 is an explanatory view of a main part of a third embodiment of an initial pressure load device according to the present invention.

FIG. 7 is an explanatory view of a main part showing a lower limit position of the initial pressure load device.

FIG. 8 is an explanatory view of a main part showing a conventional initial pressure load device.

FIG. 9 is an explanatory view of a main part showing a conventional initial pressure load device.

FIG. 10 is an explanatory view of a main part showing a conventional initial pressure load device.

[Explanation of symbols]

 Reference Signs List 1 upper die 2 presser plate 3 elastic body 4 fastening member (stepped bolt) 4a large diameter portion 5 flanged bush 5a outer flange 5b inner flange 5c opening 6 elastic body 6a through hole 7 flanged bush 7a outer flange 7b inside Tsuba 8 Stopper bolt 9 Screw rod 10 Double nut 11 Relief hole

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-B-55-35213 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) B21D 37/00 B30B 15/02 F16F 1 / 44 B21D 24/06

Claims (2)

(57) [Claims] An upper mold having a predetermined shape, a press plate for a workpiece disposed below the upper mold, and a coil spring interposed between the press plate and the upper mold. Or an elastic body made of rubber or the like, and a fastening member such as a stepped bolt whose base end is supported by the holding plate, and the elastic body is
The free end via a flanged bush initial pressure load device smell for press die formed by freely held displace the fastening member
The flanged bush extends outward from the outer peripheral surface at the upper end.
An outer flange for pressing and supporting the upper end surface of the elastic body,
At least the fastening member protrudes inward from the inner peripheral surface of the end.
And an inner collar for slidably retaining the large diameter part of
A cylindrical body provided with the elastic body at the lower end surface of the outer flange.
Fitted in the center hole of the elastic body to be locked on the upper end surface
In this state, the fastening member supported and retained by the inner collar is
An initial pressure load device for a press die, characterized in that only a lower end side is screwed to the holding plate . 2. The method according to claim 1, wherein the outer flange is provided on a contact surface side with the elastic body.
2. The method according to claim 1, wherein a gradient of 10 to 10 degrees is provided.
2. An initial pressure load device for a press die according to 1.