JP2838329B2 - Mold clamping control device of molding machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic control of a molding machine, and more particularly to an improvement of a mold clamping control device used for setting the origin position of a mold.

[0002]

2. Description of the Related Art When a molded product is obtained by a molding machine, an origin position of a mold (hereinafter referred to as an origin position) is set for mold clamping control. And a type in which the controller calculates the origin based on the input mold thickness and sets the origin from the mold clamping position side.

[0003]

However, in the setting of the origin of the mold position or the detection based on the origin, the amount of compression of the mold and the amount of expansion of the tie bar or the constituent members caused by the pressing force during the actual molding. The influence of the cost of the death of a movable plate or the like is not taken into account, and therefore, there has been a problem that stable and high-precision die control becomes difficult.

Accordingly, an object of the present invention is to provide a mold clamping control device for a molding machine capable of accurately setting the origin position of a mold and repeatedly and stably detecting the origin position of the mold.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a stationary platen 2, a mold clamping cylinder 7,
And a plurality of tie bars 6 that are tensioned between the flange portions 8 of the mold clamping cylinder 7, a movable plate 3 provided along the tie bars 6 so as to be able to approach and separate from the fixed plate 2, and a fixed plate fixed to the fixed plate 2 A mold clamping device for a molding machine, comprising a mold 4, a movable mold 5 fixed to the movable platen 3, and a hydraulic drive device 9 for supplying hydraulic fluid for driving and controlling the movable plate 3 to the mold clamping cylinder 7. In the above, the position detecting means 15 for detecting the position of the movable platen 3, the pressure detecting means 11 for detecting the pressure of the hydraulic oil supplied to the mold clamping cylinder 7, and the operation supplied to the mold clamping cylinder 7 Input means 14 for arbitrarily setting and inputting the oil pressure value, and the hydraulic oil pressure value which is connected to the position detecting means 15 and is detected by the pressure detecting means 11 and is set and input by the input means 14 Set the position of movable platen 3 when it reaches to the origin position A home position setting means 12 for,
Drive control means for inputting a hydraulic control signal to the hydraulic drive device 9 for controlling the position of the movable platen 3 corresponding to the elapse of a preset time based on the origin position set by the origin position setting means 12 10 is provided.

A position allowable value setting means 19 for setting an allowable range of the position of the movable platen 3 with respect to the origin position corresponding to a time preset in the hydraulic drive device 9 for an arbitrary time section; Movable board 3 detected by means 15
And a monitor signal output means 13 for outputting a monitor signal when the position deviates from the origin position beyond an allowable range.

[0007]

[Operation] Since the present invention is configured as described above, the origin position setting means 12 can set the origin positions of the dies 4 and 5 based on the mold clamping pressure clamped by the hydraulic drive device 9. The drive control means 10 drives and controls the hydraulic drive device 9 based on the origin position.

The monitoring signal output means 13 outputs a monitoring signal when the movable platen 3 deviates from the origin position beyond the allowable range set by the position allowable value setting means 19.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a mold clamping control device of a molding machine.
In this embodiment, a case where the molding machine 1 is constituted by a vertical press molding machine will be described.

The molding machine 1 is provided with a fixed platen 2 and a movable platen 3. A fixed die 4 is fixed to the fixed platen 2, while a movable die 5 is fixed to the movable platen 3. Reference numeral 6 denotes a plurality of tie bars, 7 denotes a mold clamping cylinder, and 8 denotes a flange.

The tie bars 6 are respectively composed of a fixed platen 2 and a movable platen 3.
Is supported between the fixed platen 2 and the mold clamping cylinder 7. The tie bar 6 guides the movable platen 3 when the movable platen 3 is driven and controlled by the mold clamping cylinder 7 and opens and closes the dies 4 and 5, and the movable platen 3 is provided so as to be able to approach and separate from the fixed platen 2. I have. Reference numeral 9 denotes a hydraulic drive, and the hydraulic drive 9 supplies hydraulic oil for driving and controlling the movable platen 3 to the mold clamping cylinder 7. The hydraulic drive device 9 is controlled by a control signal input from the drive control means 10.

The drive control means 10 has a CPU and a memory, both of which are not shown, as main components. The memory stores a program for controlling the molding machine 1 and various control data. In addition to the hydraulic drive device 9, a pressure detection unit 11 having a pressure sensor (not shown) and an origin position setting unit 12 are connected to the drive control unit 10.

The drive control means 10 includes a pressure detection means 11
A signal for controlling the driving of the mold clamping cylinder 7 is generated based on various signals input from the origin position setting means 12, the above-mentioned program and various control data. The pressure sensor of the pressure detecting means 11 is provided on the mold clamping cylinder 7,
A signal corresponding to the mold clamping pressure value of the mold clamping cylinder 7 is input to the drive control means 10.

The pressure detecting means 11 detects the fluctuation of the clamping pressure of the dies 4 and 5 based on the pressure of the hydraulic oil supplied to the clamping cylinder 7 based on the pressure detection signal inputted from the pressure sensor. . Then, a signal corresponding to the pressure value of the hydraulic oil is input to the drive control means 10, the origin position setting means 12, and the monitoring signal output means 13.

The origin position setting means 12 is for setting the origin positions of the molds 4 and 5 (or the movable platen 3). The origin position setting means 12 includes an input means 14 comprising a keyboard, a movable mold 5 or a movable mold. A position detecting means 15 for detecting the position of the panel 3 is connected. The input means 14 can arbitrarily set and input various control data to the origin position setting means 12.

In the origin position setting means 12, a pressure value (hereinafter referred to as an original pressure value) for setting a timing for setting the origin positions of the dies 4 and 5 is preset by the input means 14.
When the pressure of the hydraulic oil supplied to the mold clamping cylinder 7 detected by the pressure detecting means 11 at the time of mold clamping rises and reaches the original pressure value (for example, 70 kg / square cm), the origin position setting means 12 Movable platen 3 when the original pressure value is reached
Are set to the origin positions of the dies 4 and 5 based on the position detection means 15, and the position detection means 15 inputs a signal corresponding to this origin position to the drive control means 10.

On the other hand, the drive control means 10 is an origin position setting means.
The movable platen 3 corresponding to the lapse of a preset time as shown in FIG.
A hydraulic control signal for controlling the position of the
To enter. Accordingly, the hydraulic drive device 9 controls the driving of the mold clamping cylinder 7 based on the origin positions of the dies 4 and 5.

Since the position detecting means 15 constantly inputs a signal corresponding to the position of the movable platen 3 to the drive control means 10,
The drive control means 10 can control the drive while monitoring the position of the mold clamping cylinder 7, and the drive control means 10 constantly inputs a signal corresponding to the position of the movable platen 3 to the monitoring signal output means 13.

The drive control means 10 is provided with a timer (not shown) for measuring a monitoring time. In addition, the raw pressure value is arbitrarily determined according to the molded product,
It depends on the size, material and thickness.

The position detecting means 15 includes a position detector such as an encoder (not shown) provided on the fixed platen 2, a pinion 16, a rack 17 fixed to the movable platen 3, and the like. The pinion 16 is provided so as to be engaged and rotatable with the rack 17 over the entire stroke of the movable platen 3, and a signal corresponding to the amount of operation of the movable platen 3 is generated from the encoder directly connected to the rotation shaft. It is output to the position setting means 12 and the drive control means 10.

The monitoring signal output means 13 detects the pressure of the hydraulic oil in the mold clamping cylinder 7 by the pressure detecting means 11, and
By detecting the positions of the dies 4 and 5 via the position detection means 15, the origin position setting means 12 and the drive control means 10, when the position of the movable platen 3 is out of the allowable range from the origin position, a monitoring signal is generated. Output. This allowable range is set by the position allowable value setting means 19.

The position allowable value setting means 19 sets the allowable range as follows:
The allowable position of the movable platen 3 corresponding to the elapse of the monitoring time set in the hydraulic drive device 9 in advance is set with respect to the origin position.

The operation in the case where actual molding is performed using the mold clamping control device of the molding machine having the above configuration will be described below. Note that this embodiment is an example of a case where a resin material is molded.

First, the mold replacement will be described. When the molding of one product is completed, the mold is removed by the operator, and a new mold for molding another product is installed. That is, the fixed die 4 is fixed to the fixed platen 2 of the molding machine 1.
However, the movable molds 5 are fixed to the movable platen 3, respectively. Then, in order to obtain a pressing force suitable for the molded product, the operator inputs and sets, for example, 70 kg / cm 2 as the original pressure value from the input means 14 to the origin position setting means 12.

A hydraulic pressure is supplied from the hydraulic drive unit 9 to the mold clamping cylinder 7 for setting the origin position, and the movable platen 3 is raised to bring the molds 4 and 5 into contact. As the hydraulic pressure increases, the tie bar 6 expands due to tensile stress, and the components such as the dies 4, 5 and the movable platen 3 are compressed.

Then, the oil pressure of the mold clamping cylinder 7 detected by the pressure detecting means 11 is set as the original pressure value.
At the point in time when it becomes equal to 0 kg / cm 2, the position detecting means
The position detection value of the movable platen 3 detected by 15 is set by the origin position setting means 12 as the origin position (0) of the mold clamping control.

As described above, the origin position of the mold clamping control is set in a state in which the original pressure value is applied, that is, in consideration of the allowance for the extension of the tie bar 6, the allowance for the compression of the mold, and the allowance for the death of the constituent members. Thus, stable and high-precision mold clamping control becomes possible.

When the molds 4 and 5 are attached and the origin position determination of the mold clamping control is completed, a trial operation of press molding is performed by operating the hydraulic drive unit 9 and the drive control means 10 is operated in accordance with the obtained molded product. The above-mentioned monitoring time is set in the above timer. Further, the position allowable value setting means 19 is operated to set the allowable range of the movable platen 3 with respect to the origin position.

FIG. 2 shows the distance from the origin position of the mold to the elapse of one cycle, which is simplified for explaining the present embodiment. When a powdery resin material (not shown) is charged into the movable mold 5, a mold clamping step (see FIG. 2A) is started.

The movable platen 3 rises, and the raw material is melted between the fixed mold 4 and the movable mold 5 while being heated. At this time, the compression speed is controlled by controlling the distance from the origin position of the movable platen 3 (or the movable mold 5) to the elapse of time, and the thickness of the molded product can be made constant.

When the pressure of the hydraulic oil in the mold clamping cylinder 7 reaches the original pressure value (see FIG. 2B), the drive control means
The timer 10 starts measuring the monitoring time. During the measurement, the monitoring signal output means 13 monitors the positions of the molds 4 and 5 by the position detecting means 15 via the origin position setting means 12 and the drive control means 10.

If the position of the movable platen 3 with respect to the origin position exceeds the allowable range during the monitoring time measurement, the monitoring signal output means 13 performs a predetermined action (for example, stopping molding and driving a product quality selection shooter). Output a monitoring signal for

In this embodiment, a timer (not shown) is set as a monitoring time from the end of A to B in FIG.
± 0.1 mm from the origin position (0) of movable platen 3
Is set by the position allowable value setting means 19 as an allowable range.

As a result, an abnormal phenomenon such as uneven thickness of the molded product or burrs between the dies 4 and 5 due to the curing abnormality occurs, and the displacement of the movable platen 3 from the origin position (0) is caused. When the distance exceeds ± 0.1 mm, the monitor signal output means 13 immediately outputs a monitor signal, and effective measures for these can be taken promptly.

When the forming process is completed (see FIG. 2C),
The hydraulic drive device 9 opens the dies 4 and 5 by inputting a drive control signal to the mold clamping cylinder 7 to start the next forming process in the same manner as described above.

In this embodiment, a vertical press molding machine has been described. However, the present invention is not limited to this and may be applied to a horizontal press molding machine.

[0037]

Since the present invention is constructed as described above, the origin position of the mold can be set based on the pressure value of the hydraulic oil in the mold clamping cylinder predetermined by the origin position setting means. The compression allowance of the mold and the extension allowance of the tie bar or the death of the movable plate or the like caused by the pressing force during molding are not affected by the allowance. This allows the origin position of the mold to be accurately set by the origin position setting means, and
Since the origin position of the mold can be repeatedly and stably detected, high-precision mold control can be easily performed, so that mold clamping control, improvement of molding quality (especially thickness), and stabilization of molding quality can be easily achieved. The accuracy does not depend on the number of times of processing.

Further, the monitoring signal output means outputs a monitoring signal when the position of the movable platen with respect to the origin position deviates from the allowable range, so that it is possible to immediately cope with it by interrupting the processing, etc. Defective products can be prevented from being mixed in. In addition, since the position allowable value setting means can arbitrarily set an allowable range with respect to the origin position of the mold, accuracy and quality can be reduced according to a molded product.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a main part of an embodiment of the present invention.

FIG. 2 is a diagram showing a distance from an origin position of a mold that changes with the passage of time of one cycle by using the apparatus of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Molding machine 2 Fixed board 3 Movable board 4 Fixed type 5 Movable type 6 Tie bar 7 Mold clamping cylinder 8 Flange 9 Hydraulic drive device 10 Drive control means 11 Pressure detection means 12 Origin position setting means 13 Monitoring signal output means 14 Input means 15 Origin position detecting means 19 Position allowable value setting means

Claims (2)

(57) [Claims] 1. A fixed platen (2) and a mold clamping cylinder (7)
A plurality of tie bars (6) that are tensioned between the fixed plate (2) and the flange portion (8) of the mold clamping cylinder (7), and the fixed plate (2) is moved along the tie bar (6). A movable plate (3) provided so as to be able to approach and separate, a fixed die (4) fixed to the fixed plate (2), a movable die (5) fixed to the movable plate (3), and the movable plate A position of the movable plate (3) in a mold clamping device of a molding machine, comprising: a hydraulic drive device (9) for supplying hydraulic fluid for driving and controlling the plate (3) to the mold clamping cylinder (7). Position detecting means (15) for detecting the pressure, and pressure detecting means (11) for detecting the pressure of the hydraulic oil supplied to the mold clamping cylinder (7).
An input means (14) for arbitrarily setting and inputting a pressure value of hydraulic oil supplied to the mold clamping cylinder (7); and the pressure detecting means (11) connected to the position detecting means (15). Position setting means for setting the position of the movable platen (3) to the origin position when the pressure of the working oil detected by the operation means reaches the pressure value of the working oil set and inputted by the input means (14). (12) and a hydraulic control signal for controlling the position of the movable platen (3) corresponding to the passage of a preset time based on the origin position set by the origin position setting means (12). A mold clamping control device for a molding machine, comprising: a drive control means (10) for inputting to a hydraulic drive device (9). 2. A position allowable value setting means capable of setting an allowable range of a position with respect to an origin position of a movable platen (3) corresponding to a time set in advance in a hydraulic drive device (9) for an arbitrary time section. (19) monitoring signal output means ( 13 ) for outputting a monitoring signal when the position of the movable platen (3) detected by the position detection means (15) deviates from the origin position beyond the allowable range. The mold clamping control device for a molding machine according to claim 1, further comprising: