JPH0729318B2 - Foaming pressure detection device in foam molding machine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a foaming pressure detection device for automatically adjusting and controlling a molding die in a molding machine for manufacturing a polystyrene foam molded article.

[Prior Art] Generally, an open-close mold is used for the production of a Styrofoam molded product, and the expandable thermoplastic resin particles (hereinafter referred to as beads) are pre-expanded, or a pre-expanded mold cavity is used as it is. It is usual that after filling, steam is injected to heat-mold, then cooled, the mold is opened and the mold is released and then dried.

In this conventional foam molding machine, a mold is provided on a fixed plate and a movable plate, and it is operated so as to obtain a predetermined foaming pressure by controlling the distance between both plates. Since a switch or a proximity switch is used, at the time of setting, the position of the limit switch is manually adjusted before the molding operation in consideration of the shape thickness of the mold and the like before starting the manufacturing process.

[Problems to be solved by the invention]

Therefore, in the conventional molding work, the setting position must be manually adjusted, which is complicated and time-consuming, and in addition, many of the limit switches for mold closing completion, cracking, and ejecting mold opening completion are complicated in molding work. Since it is necessary to deploy a switch group of, not only the workability is poor, but also mechanical control due to contact often causes poor control due to inactivity due to external conditions, which causes problems in safe driving and management, In particular, the quality of the foaming pressure has a great influence on the quality of the product, and it is not possible to check the operation status numerically because the confirmation work cannot be performed during operation because of quality control, and it is not always the one that matches the ideal conditions. It was not satisfactory in terms of reliability such as lack of accuracy and delay in finding abnormal operation.

In the present invention, these conventional drawbacks are properly eliminated, and the foaming pressure condition of the Styrofoam molding operation can be numerically determined and known, and it is possible to deal with the fluctuation of many working conditions. It is an object of the present invention to provide a foaming pressure detection device for a foaming molding machine, which can be automatically controlled, the adjustment time can be significantly shortened, and the polystyrene foam molding work with high safety can be performed.

[Means for solving problems]

According to the present invention, a male die, a female die or a female die of the same type is provided so as to open and close so as to form a cavity in a die under a pressure-holding state, and the cavity is filled with a raw material to be heated and foamed. In a product for molding with a clamp frame, a clamp frame is disposed in contact with the molding die, the clamper is detachably supported on the clamp frame, a pressure receiving portion connected to the clamper via a rod, and the pressure receiving portion. Is connected to a pressure converter, and the detected pressure at the pressure receiving portion is converted into an electric signal and displayed, and the foaming pressure detection device in a foam molding machine is characterized.

[Action]

In this foam polystyrene foaming machine foaming pressure detecting device, when the cavity 3 in the mold is filled with the raw material (beads) and heated, the clamp frame 4 is pressed by the vapor pressure and the foaming gas pressure of the beads, and the clamp frame 4 The clamper 5 abutting against is moved, and the clamp lock bolt 12 and the rod 6 fixed to the clamper 5 compress the oil in the cylinder 10 serving as the pressure receiving portion 7 to generate an internal pressure. This internal pressure is generated by the pressure converter 11. The electric signal is displayed on the display unit 15, and the data processing of the computer unit 16 automatically controls the heating time and the vacuum cooling time without using a timer. The foaming pressure detected even between the molds 1 and 2 of the mold is input as an analog signal and converted to a digital signal. Control the drive unit that moves and drives the molding die by comparing it with the data and adjust the opening and closing operation of the molding die, and continuously operate the digital display to record the operating status automatically and digitally. In addition to displaying
By processing the results as data, the opening and closing work of the molding die can be optimally performed under ideal conditions, and the Styrofoam molded product can be manufactured safely and efficiently.

〔Example〕

In the embodiment of the present invention, a female mold 1 is provided on a fixed plate 21, and a male mold 2 provided on a movable plate 22 facing the fixed mold 21.
In the example shown in FIG. 3 in which is slidably mounted on the driving part, for example, the driving cylinder or the motor, the molding dies 1 and 2 of the male type, the female type or the female type are arranged so as to be openable and closable. In a mold in which a cavity 3 is formed in a mold under a pressure-holding state, a raw material is filled in the cavity 3 and heat-foamed to mold a product, a clamp frame 4 is placed in contact with the molding mold 1, A clamper 5 detachably supported on the clamp frame 4, a pressure receiving portion 7 connected to the clamper 5 through a rod 6, and the pressure receiving portion 7 are connected to a pressure converter 11 to provide the pressure receiving portion 7 The detected pressure in step 1 is converted into an electric signal and digitally displayed on the display unit 15, and the heating time and the vacuum cooling time can be automatically controlled by the computer unit 16 by the signal.

Also, the electric signal of the foaming pressure is the molding die for both moldings.
It may be applied to the interval control of 1,2, in this case the molding die 1,2
In order to automatically adjust the interval of, the detection signal of the optical sensor or the sound wave sensor is used as an analog sensor, and the signal is input to the computer unit 16 of the data processing unit as an analog signal.

The computer unit 16 can input fixed data of mold closing completion, cracking, eject, and mold opening completion in the setting section 19 as shown in FIG. 2, and can convert the analog signal into a digital signal. It can be compared with the input signal from the converter 20 and can process data.
The device including the drive unit can be controlled by the change of the above, and the operation can be automatically controlled by comparing with the data input to the computer unit 16 by the setting unit 19.

The pressure receiving portion 7 is a piston 9 urged by a spring 8.
And a piston 10 in which the piston 9 is slidably fitted and an oil filled cylinder 10 is used on one side, and a solenoid valve 17 is used on the other side.
The air for opening and closing is press-fitted by opening and closing of, and is connected to the clamper 5 by the spherical washer 13 via the lock bolt 12 to the rod 6 provided on the piston 9 and is pressed by the machine frame 14 with a constant pressure. The clamper 5 is mounted so as to straddle the clamp frame 4, and the clamper 5 is displaced by the movement of the clamp frame 4 with one end of the clamper 5 contacting the machine frame 14 serving as a fulcrum. There is. The clamper 5 and the pressure receiving portion 7 are provided in a plurality, for example, eight locations in the example of FIG. 2 with respect to the hollow cylindrical clamp frame 4, and the detected internal pressure (internal pressure compressed in the cylinder) is collected by the manifold 18 to generate a pressure. Although it can be input to the transducer 11, a pressure receiving surface of the diaphragm is formed as the pressure receiving portion 7 in the case, and this is supported by a strain bar, and the load measurement value is replaced by a load cell or a piezoelectric element having a strain gauge. May be input as an analog signal.

In the setting unit 19 of the computer unit 16, a slowdown position for switching the movable plate 22 from the high speed mold closing to the low speed mold closing before the mold closing completion, and the mold closing completion position, which is a signal for shifting to the raw material filling step. Position where the product is sandwiched between the male and female dies, and when the mold closing is stopped at low speed, or when the product does not reach the predetermined position within a certain time, the operation signal is issued to open the product and drop the sandwiched product. And the eject position of the position to control the timing of pushing down the product in the female mold with an eject pin, the change position to switch from the low speed mold opening to the high speed mold opening before the mold opening completion, and the mold opening completion position, especially the mold release is bad. In the case of products, in order to attach the product to the male mold first, the mold is opened at a certain interval and then closed again, and the opened product is attached to the female mold to facilitate release by ejecting. Operated by setting such first mold opening to control the spacing position when the case of performing Chiboru specific release.

In any case, when the male and female molding dies 1 and 2 are arranged so as to be openable and closable so that they can be molded in-mold, the intervals between the two dies are set to the mold closing completion, cracking, eject, and mold opening. Cylinder that detects completion data with analog sensor and inputs as analog signal, converts into digital signal with A / D converter, compares data with internal fixed data in data processing unit, and moves and drives the molding die or The drive unit such as a motor is controlled to adjust the opening / closing operation of the molding die.

Although the display unit 15 is digitally displayed numerically, it may be of a type that also uses an alarm lamp or a buzzer, and the fixed plate 21 may be a movable plate.

In the figure, 23 is a seal ring, 24 is an oil pipe, and 25 is an air pipe.

In the specific example of FIG. 4, the mold 1 is mounted on the fixed plate 21 with a spacer 26 interposed, and a load cell including a diaphragm 27, a strain bar 28, and a strain gauge 29 is used as the pressure receiving portion 7. There is.

〔The invention's effect〕

According to the present invention, when the cavity in the molding die is filled with beads and heated, the clamper displaced by a constant force via the clamp frame is displaced by the vapor pressure and the foaming gas pressure of the beads, and the displacement amount By compressing the oil in the cylinder of the pressure receiving part, the generated internal pressure is converted into an electric signal by a pressure converter, and the heating time and vacuum cooling time are automatically controlled without using a timer or the like,
The foaming pressure in the molding die is constantly adjusted to the ideal condition for foaming work, and the situation of this styrofoam molding work can be numerically determined and known, and high quality products can be produced, and there are many items. Automatic control can be performed under fluctuations in certain working conditions, and the adjustment time can be greatly shortened, making it possible to perform highly safe Styrofoam molding work, as well as detecting abnormal operations and adjusting molding dies. The reliability is extremely high, the internal conditions of molding in the mold can be accurately grasped and operated, the planned work can be planned by the numerical display, the handling is simple, and the man-hours required for changing the setting conditions are easy. It can be done quickly.

[Brief description of drawings]

The drawings show an embodiment of the present invention, in which FIG. 1 is a longitudinal sectional view and FIG.
The figure is an explanatory diagram of the system, and Fig. 3 is a longitudinal sectional view of a part of the state of use,
FIG. 4 is a vertical cross-sectional view of a part of another usage state. 1,2 Molding die, 3 Cavity, 4 Clamp frame, 5 Clamper, 6 Rod, 7 Pressure receiving part, 8 Spring, 9 Piston, 10 Cylinder , 11
...... Pressure transducer, 12 …… Lock bolt, 13 …… Spherical washer, 14 …… Mechanical frame, 15 …… Display, 16 …… Computer unit.

Claims (4)

[Claims] 1. A mold for molding a male mold, a female mold or female molds (1).
(2) is arranged so as to be openable and closable so as to form a cavity (3) in a mold under a pressure-holding state, and the cavity (3) is filled with a raw material and heat-foamed to form a product, A clamp frame (4) is placed in contact with the molding die (1), and a clamper (5) is detachably supported on the clamp frame (4), and a rod (6) is interposed in the clamper (5). And a pressure receiving portion (7) connected to each other and the pressure receiving portion (7) connected to a pressure converter (11) to display the pressure detected by the pressure receiving portion (7) in place of an electric signal. A foaming pressure detection device for a foam molding machine. 2. A piston (9) biased by a spring (8) and a cylinder (10) in which the piston (9) is slidably fitted and filled with oil, said pressure receiving portion (7). The foaming pressure detection device according to claim 1, wherein the foaming pressure detection device is a shock absorber. 3. The foaming pressure detecting device according to claim 1, wherein the pressure receiving portion (7) is a load cell in which a pressure receiving surface of a diaphragm is supported by a strain bar in a case. 4. The clamper (5) is provided with a lock bolt (1).
Any one of claims 1 to 3, which comprises 2) and a spherical washer (13) and is connected to the rod (6) and is mounted on a machine frame (14). The foaming pressure detection device according to one of the items.