JPH0614897Y2 - Mold work positioning device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention is a mold work for positioning and holding a work to be pressed between an upper mold and a lower mold on the lower mold. Retaining structure.

<Prior Art> Conventionally, a metal plate material is formed into, for example, a bottomed tubular shape by a process such as deep drawing, redrawing, and restriking.

When performing such processing, the work is conveyed to the mold by a feeding device such as a transfer feed. However, the positioning of the work with respect to the mold depends on the above-mentioned feeding device or the lower mold. Stand the guide pin,
The work is placed along the pin and placed on the lower mold.

However, especially when performing finishing processing such as restriking, it is necessary to position the work relatively accurately with respect to the mold, and the above-mentioned positioning causes the work to be deviated, so the processing is performed as it is. Then, there is a drawback in that not only the work is defectively machined, but also the mold side is easily worn due to an unbalanced load, and the life is shortened.

<Problems to be Solved by the Invention> In view of such drawbacks of the conventional technique, a main object of the present invention is to provide a work holding structure of a die capable of stably holding a work to be pressed. .

<Means for Solving the Problems> According to the present invention, such a purpose is to position and hold the work to be pressed between the upper die and the lower die with respect to the punch and the die. And a work supporting member which is elastically supported by the lower mold via first spring means for generating upward elastic force, and which supports the work in a point manner. A centering member that is elastically supported by the upper die via second spring means that generates downward elastic force, and has a lower end portion that positions the head of the workpiece. It is achieved by providing a work positioning device for a die, characterized in that the biasing force of the first spring means is made stronger than that of the second spring means.

<Operation> In this way, in the mold clamping process, when the centering member provided on the upper die comes into contact with the head of the work placed on the work supporting member provided on the lower die, Displaces upwards before the work support member. Therefore, the work point-supported on the work support member can easily move along the lower end of the centering member, and the work is positioned with high precision before being pushed into the lower die and the punch.

<Embodiment> Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a cross-sectional view showing the structure of a press molding apparatus to which the present invention is applied, which may be used for wrist-liking. The press molding apparatus has a fixed lower mold unit 1 and a movable upper mold unit 2. And have.

A cylindrical lower punch 4 is fixed to a central portion of a bottomed cylindrical lower die holder 3 in the lower die unit 1 via a punch retainer 5. An annular lower die 7 is provided at the inner edge of the annular lower die holder 6 fixed to the opening of the lower die holder 3. From the center of the opening of the lower die 7, the tip portion of the lower punch 4 described above projects. Further, as also shown in FIG. 2, a plurality of pins 16 for roughly positioning the work 18 are provided so as to project upward at appropriate places on the lower die 7.

A knockout holder 10 and a lower knockout member 9 fixed to the holder are provided on the outer periphery of the lower punch 4 in the opening of the lower die 7 so as to be vertically movable. The knockout holder 10 has four lift-up pins 15 as work supporting members provided to penetrate the lower knockout member 9, and a first lift-up pin 15 that elastically biases the pins upward.
A spring holder 13 which receives a spring 14 as a spring means therein is fixed. The lift-up pin 15 projects from the opening of the upper end surface of the lower knockout member 9 so as to be retractable (Fig. 2).

Inside the lower die holder 3, a cushion plate 12 biased upward by a spring 11 is loosely fitted to the outer periphery of the punch retainer 5 so as to be vertically movable. Four pins 17 are projectingly provided on the upper end surface of the cushion plate 12, and the pins 17 project upward from the opening of the lower die holder 6. The upper end surface of the cushion plate 12 contacts the lower end surface of the lower knockout holder 10 to support the holder and the lower knockout member 9.

On the other hand, on the upper die unit 2 side, a cylindrical shape corresponding to the lower punch 4 and the lower die 7 described above is provided at the center lower end portion of the upper die holder 20 connected to a vertical driving device (not shown). The ring punch 21 is provided so as to project downward. Further, on the lower end surface of the upper die holder 20, four pushers 22 corresponding to the pins 17 are provided so as to project downward.

A pad 25 is fitted on the outer periphery of the ring punch 21 so as to be vertically movable. This pad 25 has a spring 27
The stopper 23 provided on the lower end surface of the upper die holder 20 defines the moving range of the upper die unit 2 while being urged downward by the.

In the center inner hole 29 of the ring punch 21, a knockout pin 32 as a centering member, an intermediate member 31,
The base end member 30 and the base end member 30 are received in order from the lower side so as to be vertically movable. Between the base member 30 and the intermediate member 31, and between the intermediate member 31 and the knockout pin 32, springs 33 and 34 for separating the two members from each other.
Is provided. Further, a stopper 35 that engages with the base end member 30 and a stopper 36 that engages with the knockout pin 32 are provided at both upper and lower ends of the intermediate member 31, and the base end member 30, the intermediate member 31, and the knockout pin 32 are provided by both stoppers. The relative movement range between and is defined.

Here, the knockout pin 32 has a lower free end portion 37.
Has a shape that matches the shape of the head portion 18a of the work 18.

The biasing force of the spring 33 is set stronger than that of the spring 14 described above. The urging force of the spring 34 as the second spring means is
Is set weaker than. That is, the urging forces of these springs are in the relationship of spring 34 <spring 14 <spring 33.

The base end member 30 is biased downward by a urethane spring 38 received in the intermediate recess 20a of the upper mold holder 20. Further, the base end member 30 is formed with an enlarged diameter portion 30a located in the recess 20a, and the lower shoulder surface of the enlarged diameter portion abuts on the upper end surface of the ring punch 21 so that the base end member 30 is exposed. The moving range provided in the upper mold unit is specified.

Reference numeral 40 in FIG. 2 indicates four guide pins that guide the upper mold unit 2 in the vertical direction.

Next, the operation procedure of the press molding apparatus to which the present invention is applied will be described.

As shown in FIG. 1, the work 18 is placed on the lift-up pin 15 while being guided by the positioning pin 16 by transfer feed (not shown), and the upper mold unit 2 is lowered. Then, first, the free end portion 37 of the knockout pin 32 on the upper die unit 2 side comes into contact with the head portion 18 at the center of the work 18, and the spring 34 having the weakest biasing force is compressed, as shown in FIG. 32 strikes the intermediate member 31.

Next, as shown in FIG. 4, the spring 14 is compressed,
The lift-up pin 15 is retracted inside the lower knockout member 9, and the lower end surface of the work 18 is located at the lower knockout member 9.
Abut the upper end surface of. At this time, knockout pin 32
In the process of gradually immersing in the inner hole 29 and in the process of gradually immersing the lift-up pin 15 in the lower knockout member 9, the contact area with respect to the work 18 is relatively small, that is, sliding. The work 18 is easily moved on the lift-up pin 15 having a small resistance, and the work 18 follows the lower end of the knockout 32 before being pushed into the lower punch 4 and the lower die 7. As a result, the work can be easily centered.

Then, the pusher 22 contacts the pin 17 and presses the pin to compress the spring 11 and lower the cushion plate 12. At the same time, the knockout holder 10, the knockout member 9, and the work 18 supported on the cushion plate 12 descend.

Thereafter, as shown in FIG. 5, the lower end surface of the pad 25 contacts the upper end surface of the lower die 7, the spring 27 is compressed through the pad, and the ring punch 21 relatively projects downward. The work 18 is pressed together with the lower die 7 and the lower punch 4. At this time, knockout pin 3
By pressing 2 from the lower side, the spring 35 between the base end member 30 and the intermediate member 31 is compressed in the inner hole 29, and the base end member 31 further rises, and the urethane spring 3
8 are compressed. The position of the lower knockout member 9 at this time is defined by the lower end surface of the lower knockout holder 1 contacting the upper end surface of the punch retainer.

On the other hand, when the mold is opened, the operation reverses to the above operation. That is, when the upper mold unit 2 is raised from the state shown in FIG. 5, the pad 25 urged by the spring 27,
The ring punch 21 rises while urging the work 18 downward by the urethane spring 38 and the knockout pin 32 urged by the spring 35 via the base end member 30 and the intermediate member 31, and the work 18 is lifted from the ring punch 21. Release. At this time, on the lower mold unit 1 side, the cushion plate 12 rises due to the urging force of the spring 11.

After that, the cushion plate 12 contacts the lower end surface of the lower knockout holder 10 and raises the holder, so that the work 18 on the lower knockout member 9 is released from the lower die 7 and the lower punch 4 (No. (Fig. 4).

Next, as shown in FIG. 3, the lift-up pin 15 is pushed by the urging force of the spring 14 to a position where the head portion 15a of the pin comes into contact with the internal shoulder surface 9a of the lower knockout member 9,
While supporting the work 18, it projects from the upper end surface of the lower knockout member 9. Thereafter, the free end portion 37 of the knockout pin 32 is projected downward from the inner hole 29 of the ring punch 21 by the biasing force of the spring 34 on the upper die unit 2 side while holding the head portion 18a of the work 18, and finally the first It separates from the work 18 as shown in FIG.

Here, for example, when the mold opening is performed at a high speed, there is a problem that the work knocks out in the releasing direction or the holding position is displaced due to the urging force of the lower knockout member 9 and the lift-up pin 15 against the work 18. , Knockout pin 3 by the urging force of spring 34 until the end of mold opening
This can be avoided by urging and holding the work 18 toward the lower mold side by the free end portion 37 of No. 2.

<Effect of the device> As described above, according to the present invention, since the work is positioned on the upper mold side while the work is supported on the lower mold by points, the sliding resistance between the work and the lower mold is increased. Is reduced and the work to be machined can be easily and accurately positioned with respect to the die, so that the occurrence of machining defects can be prevented. Further, it is possible to prevent the wear of the mold from increasing due to an unbalanced load, so that the life of the mold is extended. From the above, the effect of the present invention is great.

[Brief description of drawings]

FIG. 1 is a sectional view showing the structure of a press forming apparatus to which a work holding structure according to the present invention is applied. FIG. 2 is a view of FIG. 1 viewed from the line II-II. 3 to 5 are operation explanatory views of a press forming apparatus to which a work structure according to the present invention is applied. 1 ... Lower mold unit, 2 ... Upper mold unit 3 ... Lower mold holder, 4 ... Lower punch 5 ... Punch retainer, 6 ... Lower die holder 7 ... Lower die, 9 ... Lower side Knockout member 9a ...... Shoulder surface 10 ...... Lower knockout holder 11 ...... Spring, 12 ...... Cushion plate 13 ...... Spring holder 14 ...... Spring, 15 ...... Lift-up pin 15a ...... Head, 16 ...... Positioning Pin 17 ... Pin, 18 ... Workpiece 18a ... Head, 20 ... Upper mold holder 20a ... Recess, 21 ... Ring punch 22 ... Pusher, 23 ... Stopper 25 ... Pad, 27 ... Spring 29 ... Inner hole, 30 ... Base end member 30a ... Expanded part, 31 ... Intermediate member 32 ... Knockout pin 33, 34 ... Spring 35, 36 ... Stopper, 37 …… Free end 38 …… Urethane spring 40 …… Guide pin

Claims (1)

[Scope of utility model registration request] 1. A work positioning device for a die for positioning and holding a work to be pressed between an upper die and a lower die with respect to a punch and a die, the elastic force being upward. Via a first spring means for generating a force and a work supporting member elastically supported by the lower die and supporting the work in a point manner, and a second spring means for generating a downward elastic force. A centering member that is elastically supported by the upper die and has a lower end portion that positions the head portion of the work; and the urging force of the first spring means is applied to the second spring. A work positioning device for a die, characterized in that it is stronger than the means.