KR910007998B1 - Method and apparatus for controlling surface temperature of molding roll in foam extrusion molding apparatus - Google Patents

Abstract

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Description

Method and apparatus for controlling surface temperature of molding roll in foam extrusion molding apparatus

Figure 1 is a plan view of the main part showing the center around the semi-circular forming roll is installed the temperature control device of the present invention.

2 is an enlarged cross-sectional view taken along the line A-A of FIG.

3 is a cross-sectional view showing a modification of the air supply pipe shown in the partially enlarged view of FIG.

Figure 4 is a perspective view showing the separated appearance of the air supply pipe of the present invention thermostat.

5 is a perspective view showing a modified embodiment of FIG.

6 is a principal part clear view showing another modified embodiment of the present invention.

7 is a principal part clear view showing another modified embodiment of the present invention.

8 is a cross-sectional view taken along the line B-B in FIG.

Figure 9 is a schematic diagram for explaining the temperature control method of the present invention.

The present invention relates to a method and apparatus for controlling the surface temperature of upper and lower semi-circular forming rolls for molding a foam extruded from a die hole in a porous plastic foam molding apparatus.

In general, the plastic foam molding method uses a styrene or similar foam molding thermoplastic resin containing a blowing agent to supply the die hole into the vacuum chamber, which maintains the vacuum state through the melt in a molten state at a temperature higher than the appropriate temperature, and then immediately expands and moves radially. In addition, a molding method is adopted in which a plurality of semi-circular forming rolls, a surface treatment machine, and a conveyor are passed to obtain a foam having a predetermined thickness and a predetermined density.

Related to such conventional foam molding methods or apparatuses are described in detail in Patent Publication Nos. 83-1231,1232,1233,1234,1235,1236 and 1237 83-2740, 85-1876 and the like.

However, in the prior art already described above, the material entering the vacuum chamber through the die hole is foamed by self-expansion by internal vacuum, and passes through semi-circular upper and lower forming rolls to form a foam having a predetermined thickness and a predetermined density. When the upper and lower semi-circular forming rolls are used continuously for a long time, the upper and lower semi-circular moldings are formed with the rise of the internal temperature of the device because the upper and lower rolls pass directly through the holes of the die in the state of melting the material. This results in an increase in roll surface temperature.

The surface temperature rise of the upper and lower semi-circular forming rolls causes problems such as wrinkles, defects and deformations on the surface of the foam which is continuously moved and formed by melting and attaching a part of the foamed material to the upper and lower semi-circular forming rolls. There are some disadvantages that can adversely affect the quality of the product.

In particular, in order to solve the above problems, in order to remove the foreign matter adhering to the surface of the upper and lower semi-circular forming rolls, the entire apparatus must be stopped, the pressure inside the vacuum chamber must be raised to atmospheric pressure, and then some devices must be separated. As it is possible to carry out the removal work, there is a huge economic loss, such as the discontinuation of the work and the dismantling operation which must be done on a daily basis. .

The present invention has been researched and developed on the basis of the basic principle that the above-mentioned problems can be solved by maintaining the proper temperature by cooling the temperature inside the vacuum chamber, in particular, the surface temperature of the upper and lower forming rolls consisting of semi-circles. .

The main purpose of the present invention is to maintain a constant surface temperature of the upper and lower rolls of the foam molding apparatus to prevent the sticking of a part of the material to the upper and lower semi-circular forming rolls, and to control the temperature of the product to improve the quality of the product. To provide a method and apparatus.

It is another object of the present invention to maintain a high production quality and to facilitate the production of a plastic foam molded article continuously and to maintain a high productivity.

Another object of the present invention is to provide a method and apparatus for controlling the surface temperature of the upper and lower semi-circular forming rolls without any influence on the basic production line to be extruded, foamed molding.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

In order to achieve the above object of the present invention, the present invention will be described with respect to several embodiments in various methods and apparatuses that can be made based on the above-described basic principles.

1, 2 and 4 illustrate an embodiment of the present invention, a semi-circular forming roll (1, 2, 3, 4, 5) arranged in pairs on the top and bottom horizontally The air supply pipe 6 having the same curvature is installed adjacent to the upper and lower portions of the first stage forming rolls 1 and 1, but the air supply tube 6 faces the first stage forming rolls 1 and 1. A plurality of micropores 7 are formed in the longitudinal direction, respectively, and a flow rate control valve VE is installed at an inlet part installed through the front wall 8 so as to supply air having a constant temperature from the constant temperature chamber.

In addition, a bulk head 8 is provided with a die 10 at the center and a surface finisher 11 at the rear of the semi-circular forming roll 5 so that the raw material 12 is vacuum chamber 13 from the die 10. 3) It is transported through the surface finisher 11 while passing through the above-mentioned semi-circular forming rolls 1, 2, 3, 4, 5 while radially spreading and foaming according to the internal characteristics.

FIG. 3 shows a modified embodiment in which the micropores 7 have different shapes in the above-described embodiment, and show that a plurality of micropores 7 'and 7' are formed in two rows in the longitudinal direction.

FIG. 5 illustrates an embodiment in which the structure of the air supply pipe 6 is modified in the embodiments shown in FIGS. 1 to 4, which has a branching in two directions from the inlet. The embodiment formed in one side of the up and down type is shown.

Figure 6 shows another modified embodiment of the present invention, the air supply pipe (6-1,6-2,6-3,6-4) for each of the semi-circular forming rolls (1,2,3,4,5) , 6-5) is installed adjacent to the upper and lower parts.

7 and 8 show yet another modified embodiment of the present invention, the air supply hole (1a) is formed in the center of the axis (1A) of the semi-circular forming roll (1) and the air supply hole (1a) and the shaft Between the outer circumferential one side of 1A, a plurality of fine holes 1b are formed in the longitudinal direction of the shaft 1A so that the air supply pipe 6 'and the air supply hole 1a provided with a flow control valve VE are provided. By connecting the air supply pipe (6`), through the air supply hole (1a) is an embodiment that can control the surface temperature of the semi-circular forming roll (1) by the injection of air through the fine hole (1b).

Unlike the previous embodiment, only some of the semi-circular forming rolls 1, 2, 3, 4, 5, for example, may be installed and used.

In addition, the inlets of the air supply pipes 6-1, 6-2, 6-3, 6-4, and 6-5 may be separately configured as shown in FIG. 6, or may be configured as a single branch if necessary. You may.

Figure 7 illustrates a system diagram for temperature control of the present invention, the temperature sensor (TS) is installed on each of the semi-circular forming roll (1, 2, 3, 4, 5) or the air supply pipe 6 is installed adjacent It is installed on one side of the forming roll.

Here, the flow regulating valve VE can use a conventional solenoid valve.

The display D and the microprocessor MP are usually installed outside of the device. Here, the microprocessor MP receives data about the temperature of the internal forming rolls 1, 2, 3, 4, and 5 from the temperature sensor TS, and the condition inside the device is displayed on the display D. The input and calibration of data by the operator OR (usually by selecting an appropriate temperature condition required for the semi-circular forming rolls 1, 2, 3, 4 and 5) can be performed. The microprocessor MP compares the temperature value input from the temperature sensor TS and the data input by the operator OR to control the opening and closing of the flow control valve VE.

At this time, the number of the temperature sensor TS or the number of the flow control valve VE may be selected according to the conditions installed inside the device.

Next, the operation and effects of the present invention will be described based on the above description.

First, as in the conventional method, when a material such as styrene or a thermoplastic resin such as a polyurethane mixed with a blowing agent is melted to an appropriate degree and sent out into the vacuum chamber 13 through the hole of the die 10, the die hole is expanded immediately. The surface temperature of the upper and lower semi-circular forming rolls (1, 2, 3, 4, 5) is detected by the temperature sensor (TS) and appears on the display (D) while foaming out from the radial shape.

When the surface temperature of the semi-circular forming rolls (1, 2, 3, 4, 5) according to the characteristics of the material to input the data of the appropriate temperature by the operator (OR) to the microprocessor (MP) This data is displayed on the display (D) and the surface temperature of the semi-circular forming rolls (1, 2, 3, 4, 5) and the input appropriate temperature data are compared and calculated inside the microprocessor (MP). This is done continuously and the operation of the flow control valve (VE) by the signal generated from the microprocessor (MP) is performed as follows.

First, when the surface temperature of the semi-circular forming rolls (1, 2, 3, 4, 5) detected by the sensor (TS) is higher than the appropriate temperature data input to the microprocessor (MP) by the operator (OR) In response to the command signal from the microprocessor (MP), the flow control valve (VE) automatically opens and maintains the maximum open state, whereby air of constant temperature is supplied from the constant temperature chamber to the air supply pipe (6 or 6-1, 6-2, 6-3). , 6-4,6-5,6`) and micropores (1b, 7,7`) are supplied to the upper and lower semi-circular forming rolls (1,2,3,4,5) via a vacuum chamber. Due to the characteristics of (13), the pressure inside the vacuum chamber (13) is significantly lower than the constant temperature chamber, so that air is naturally sucked from the constant temperature chamber into the vacuum chamber (13) by the pressure difference, and thus uniformity through the micropores (1b, 7, and 7`). The injection is continued to cool the surface of the semi-circular forming rolls (1, 2, 3, 4, 5) until the proper temperature input to the microprocessor (MP) is reached.

Second, when the surface temperature of the semi-circular forming rolls (1, 2, 3, 4, 5) detected by the detection sensor (TS) coincides with the appropriate temperature data input to the microprocessor (MP) by the operator (OR). In response to the electrical signal from the microprocessor MP, the flow regulating valve VE is kept in a constant state, and the flow rate of the air flowing into the vacuum chamber 13 is continuously supplied in a constant amount, thereby semi-circular forming rolls 1, 2, 3 The surface temperature of (4, 5) is kept in a state consistent with the appropriate temperature data.

Third, when the surface temperature of the semi-circular forming rolls (1, 2, 3, 4, 5) detected by the sensor (TS) is lower than the appropriate temperature data input to the microprocessor (MP) by the operator (OR) In response to the electrical signal from the microprocessor (MP), the flow control valve (VE) is closed and the air in the constant temperature chamber supplied into the vacuum chamber 13 is stopped and the semi-circular forming rolls (1, 2, 3, 4, 5). The flow rate control valve VE is kept closed until the surface temperature of e) reaches a temperature consistent with the appropriate temperature data.

As described above, the surface temperature of the semi-circular forming rolls 1, 2, 3, 4 and 5 can be kept constant by the continuous operation, and the timing of inputting the data of the appropriate temperature by the operator OR has already been mentioned. As described above, the device may be input at the initial stage after starting the operation of the device, or may be input at the preparation stage before starting the operation of the device.

In addition, instead of the automatic adjustment method shown in FIG. 7, the temperature of the vacuum chamber 13 or the surface temperature of the semi-circular forming rolls 1, 2, 3, 4, and 5 are manually checked to manually open or close the flow control valve VE. By adjusting the degree, a manual operation method for maintaining the surface temperature of the semi-circular forming rolls 1, 2, 3, 4 and 5 at an appropriate temperature state is also possible.

Therefore, the present invention as described above is to maintain the surface temperature of the upper and lower rolls at an appropriate temperature state to prevent the phenomenon that a part of the material is attached to the upper or lower rolls during the operation of the foaming device and accordingly the product made of foam It can maintain the quality of the product in good condition and can be continuously made without interruption of production, which can greatly improve productivity and at the same time, it is easy to install and has no effect on the existing equipment line in which I / O molding is performed. To have.

Finally, the present invention can be variously modified as shown in the various embodiments as already mentioned, but when such various modifications are consistent with the technical spirit of the present invention, the various modifications as described above will be described in the claims of the present invention. I want to know that it belongs to.

Claims (5)

In the foam extrusion molding apparatus, an air supply pipe is installed adjacent to the upper and lower portions of the semi-circular forming roll, and a plurality of fine holes are formed in the air supply pipe, and a flow control valve is installed at the inlet, and the air supply pipe is connected to the constant temperature chamber. The surface temperature control device of the forming roll, characterized in that the temperature sensor is installed adjacent to the semi-circular forming rolls or semi-circular forming rolls, and the display and the microprocessor are installed outside the apparatus. 2. The surface temperature control apparatus of claim 1, wherein the air supply hole is formed at the center of the shaft of the semi-circular forming roll, and a plurality of fine holes are formed in the longitudinal direction of the shaft to be connected to the air supply pipe. An air supply pipe having a plurality of micropores is formed adjacent to the upper and lower portions of the semi-circular forming roll, and a flow control valve is installed at the inlet, but the flow rate of the air supply pipe is controlled by controlling the opening and closing of the flow control valve. Method of controlling the surface temperature of the forming roll in the foam extrusion molding apparatus, characterized in that to control the surface temperature of the semi-circular forming roll. 4. The method according to claim 3, wherein the air supply hole is formed at the center of the semi-circular forming roll, and a plurality of fine holes are formed in the longitudinal direction of the shaft and connected to the air supply pipe. The surface temperature of the semi-circular forming roll is detected by a temperature sensor and the appropriate temperature data by the operator is input to the microprocessor, and the comparison operation of the surface temperature and the appropriate temperature data in the microprocessor. The method of controlling the surface temperature of the semi-circular forming roll in the foam molding apparatus, characterized in that the operation of the flow control valve is performed by the signal generated from the microprocessor to adjust the surface temperature of the semi-circular forming roll.

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