JPH09220697A - Press device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To practically detect the pressure impressed on a material to be pressed, and to control the quality in the high precision. SOLUTION: In a press device which provides at least an upper die 1 and a lower die 2, puts a material 3 to be pressed between both dies 1, 2 and which presses and forms it, a pressure sensor 4 is installed on the one side, at least, between the upper die 1 and the lower die 2, and the pressure receiving face 5 of this pressure sensor 4 is brought in contact with the material 3 to be pressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a press device,
In particular, it relates to a device capable of detecting the press pressure.

[0002]

2. Description of the Related Art As is well known, when manufacturing a brake pad used for a vehicle brake or the like, a resin (pressed material) containing a friction material or metal powder is put into a three-division type mold, A method of solidifying the internal resin by applying a high pressure (press) to the mold is adopted.

However, it is known that the quality of the brake pad depends on the pressing pressure.
That is, if the pressure varies, the hardness and wear resistance of the brake pad also vary, so it is necessary to monitor the brake pad so that the pressure is always constant.

There are various methods for detecting the press pressure, but when the press is performed by a hydraulic press device, there is a method in which a pressure sensor is inserted in a rod or the like connecting a piston of the hydraulic device and a die. . It is also possible to calculate the press pressure by detecting the hydraulic pressure itself.

The pressure detected by such a method is considered as the actual pressure on the material to be pressed, and the value is controlled so as to be always constant, whereby quality control is performed.

[0006]

However, the pressure value obtained as described above is only the pressure generated on the side of the pressing device, and is not the same as the pressure actually applied to the material to be pressed. May occur. In particular, when a large number of dies are driven by a single pressing device, the pressing force may not be dispersed uniformly due to mechanical problems, and there is a risk that the pressing pressure may vary depending on the dies.

This variation is also caused by the weight of the material to be pressed, the density difference between the left and right, the parallelism of the press, the mold distortion, and the like. The present invention has been made in view of the above matters,
It is a technical object to provide a press device capable of actually detecting the pressure applied to the material to be pressed and performing quality control with high accuracy.

[0008]

In order to solve the above-mentioned technical problems, the present invention comprises at least an upper mold 1 and a lower mold 2, and a material 3 to be pressed is put between both molds 1, 2. The press device for press-molding this has the following configuration.

That is, in the structure of claim 1, a pressure sensor 4 is provided on at least one of the upper die 1 and the lower die 2, and the pressure receiving surface 5 of the pressure sensor 4 is the pressed material 3
It was placed so that it touched. [Upper mold 1] The upper mold 1 does not necessarily mean a mold located on the upper side, but when combined with the lower mold 2, the outer wall and the inner wall of the upper mold 1 are brought into close contact with each other just like a piston and a cylinder, and the surface of the upper mold 1 is A mold is shown in which the (lower surface) and the surface (upper surface) of the lower mold 2 can come into contact with or come close to each other. [Lower mold 2] The lower mold 2 is used in combination with the upper mold 1, but the lower mold 2 does not necessarily have to be integrated, and is a concept including a plurality of other molds such as a middle mold. In short, upper mold 1
The lower mold 2 is a minimum required component, and the number of divided molds and the shape are not limited.

The pressing step by the upper mold 1 and the lower mold 2 may be a step of simply pressing the material 3 to be pressed, or a step of pressing the material 3 to be pressed while heating it. [Pressed Material 3] The pressed material 3 is a raw material mainly composed of powder, and after press molding, for example, becomes a brake pad or a clutch plate. [Pressure Sensor 4] As the pressure sensor 4, a strain gauge such as a mechanical type or a piezoelectric element is used.
Is exposed on the surface of the upper die 1 or the lower die 2 that contacts the pressed material 3. The pressure sensor 4 is
It is desirable to place it in the center of the mold.

The pressure receiving surface 5 of the pressure sensor 4 may be set flush with the surface of the upper mold 1 or the lower mold 2, or may be provided so as to project or recede from the surface.
With the above-described configuration, the actual pressure applied to the material 3 to be pressed can be detected, and it can be used as a guideline for correcting the excess or deficiency of the pressure.

In particular, when a large number of molds are driven by a single press device, the distribution of the pressing force is often not uniform, but the length of the rod connecting the press devices and the molds is finely adjusted. By doing so, it is possible to achieve uniformity.

Further, in the structure of claim 2, a plurality of the pressure sensors 4 are provided. Thereby, even if the pressed material 3 is large, the pressure distribution of the pressed material 3 can be accurately detected,
It serves as a guide for adjusting the press equipment.

Further, in the structure of claim 3, the pressed material 3 is a molded material of a brake pad. This allows
It is possible to obtain a highly accurate brake pad.

[0015]

[First Embodiment] A first embodiment of the present invention will be described with reference to FIG.

In this embodiment, the present invention is applied to a device for molding a brake pad. The lower mold 2 is placed on the base 9, and the cylindrical middle mold 6 is separably provided on the lower mold 2. The inner surface of the middle die 6 is in the shape of a cylinder, and the upper die 1 formed in the shape of a piston is fitted in the middle die 6 so as to be insertable and removable.

The material 3 to be pressed is put in a portion surrounded by the upper die 1, the lower die 2 and the middle die 6. A pressing shaft 7 of a pressing device (not shown) is provided above the upper mold 1, and the tip of the pressing shaft 7 abuts the upper surface of the upper mold 1. The pressing shaft 7 and the upper mold 1 may be integrally formed or may be formed so as to be connectable with each other.

A cavity portion 1a is formed in the upper die 1, and the cavity portion 1a is opened at the center and the side surface of the lower surface of the upper die 1. Then, the pressure sensor 4 is provided in a portion where the hollow portion 1 a opens on the lower surface of the upper mold 1. The pressure sensor 4 is attached so that its pressure receiving surface 5 is substantially flush with the lower surface of the upper mold 1. A cord 8 is connected to the pressure sensor 4, and the cord 8 is connected to a measuring device (not shown) to display a pressure value.

During the actual pressing, the pressure receiving surface 5 of the pressure sensor 4 comes into contact with the material 3 to be pressed. The pressure sensor 4 may be provided on the lower mold 2 side.

In the above-mentioned structure, as shown in FIG. 1, an upper die 1, a lower die 2 and an intermediate die 6 are assembled, and a material 3 to be pressed, which has been previously put in a fixed amount, is pushed into the die. . Then, when the upper die 1 is pressed by the pressing shaft 7, the pressure of the pressing shaft 7 presses and presses the material 3 to be pressed.

At that time, the pressure of the pressed material 3 is transmitted to the pressure sensor 4 as it is, and the pressure actually applied to the pressed material 3 is sent out from the cord 8 to the outside. Then, the pressure value is read, and if the pressure is not normal, the press device is adjusted. It is also possible to automatically read the output from the code 8 and automatically adjust the press device according to the value. [Second Embodiment] A second embodiment of the present invention will be described with reference to FIG.

In the second embodiment, an example of driving a plurality of molds by one press device 10 will be described. The pressing device 10 is a hydraulic type, and the pressing shaft 7 is provided so as to be freely movable in and out. A lateral beam 11 is provided at the tip of the pressing shaft 7, and four screw-type pressing shafts 7 are screwed into the lateral beam 11 so as to penetrate therethrough. Four sets of the upper mold 1, the lower mold 2, the middle mold 6 and the pressure sensor 4 are provided below each pressing shaft 7. The lower end of the pressing shaft 7 is in contact with the upper surface of each upper mold 1.

In the above-mentioned structure, when the press device 10 is moved downward, the transverse beam 11 and the pressing shaft 7 are accompanied with this.
Moves down. This allows four sets of molds to operate simultaneously. Here, the signal from the pressure sensor 4 is measured, and the deviation from the prescribed pressure is measured. When there is a deviation, the pressing shaft 7 is rotated so as to minimize the deviation, and the height of the pressing shaft 7 (the length from the cross beam 11 to the lower end of the pressing shaft 7) is finely adjusted to average the pressing force. .

It is needless to say that the measurement and adjustment can be automated in this embodiment as well. [Third Embodiment] A third embodiment of the present invention will be described with reference to FIG. This embodiment is particularly effective when the material 3 to be pressed is large.

That is, when the material 3 to be pressed is large, the pressure may vary depending on its part. For example, this causes a pressure difference depending on the part even if the positional accuracy between the molds is poor or the accuracy of the mold itself is poor.

Therefore, a total of four pressure sensors 4 are provided on the upper mold 1. The position is one in the center and 120 to each other.
Three are provided with an angle difference of degrees. Thereby, even if the material 3 to be pressed is large, the pressure distribution of the material 3 to be pressed can be accurately detected, and it serves as a guideline for adjusting the press device.

[0027]

According to the present invention, a pressure sensor is provided on at least one of the upper die and the lower die, and the pressure receiving surface of the pressure sensor is arranged so as to contact the material to be pressed. The applied pressure can be detected.

Therefore, the quality control can be performed with high accuracy by correcting the press pressure and the like based on this actual pressure value. Further, it is possible to provide a press device that can manage molded products with high accuracy in this manner with a simple configuration at low cost.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a main part according to a first embodiment of the present invention.

FIG. 2 is a side view of the entire apparatus showing the second embodiment of the present invention.

FIG. 3 is a bottom view of the upper mold showing the third embodiment of the present invention.

[Explanation of symbols]

 1 ・ ・ Upper mold 1a ・ ・ Cavity 2 ・ ・ Lower mold 3 ・ ・ Pressed material 4 ・ ・ Pressure sensor 5 ・ ・ Pressure receiving surface 6 ・ ・ Medium size 7 ・ ・ Pressing shaft 8 ・ ・ Cord 9 ・ ・ Base 10 ..Pressing device 11 ..

Claims (3)

[Claims] 1. A press device comprising at least an upper mold and a lower mold, wherein a material to be pressed is put between both molds and pressure-molded, wherein a pressure sensor is provided in at least one of the upper mold and the lower mold. And a pressure receiving surface of the pressure sensor is in contact with the material to be pressed. 2. The press device according to claim 1, wherein a plurality of the pressure sensors are provided. 3. The press device according to claim 1, wherein the material to be pressed is a molded material of a brake pad.