KR20030088935A - Control method of gate valve for injection molding - Google Patents

Abstract

PURPOSE: A method for controlling a gate valve for injection molding is provided to injection-mold two or more resins into a product by successively controlling the gate valve. CONSTITUTION: A method for controlling a gate valve comprises the steps of: inputting information on a product cavity(S10); operating resin injection unit, and supplying resin(S20); operating a gate timer(S30); receiving counted operating time(S40); determining whether the received operating time is the open time of gate valves(S51,S52); opening the gate valves if the received operating time is the open time of gate valves(S61,S62); determining whether the operating time is the close time of the gate valves while the gate valves is opened(S71,S72); and closing the gate valves if the operating time is the close time of the gate valves(S81,S82).

Description

Gate valve control method for injection molding {CONTROL METHOD OF GATE VALVE FOR INJECTION MOLDING}

The present invention relates to a method for controlling a gate valve for injection molding, and more particularly, an injection molding gate which enables injection molding of a product made of at least two resin materials by adjusting a resin supply timing through sequential control of the gate valve. It relates to a valve control method.

In general, injection molding is one of the molding processing methods of plastics, and forms the center of a method of molding thermoplastic resins.

In the injection molding process, first, a compound made of several mm chips of cylindrical or square shape is added to a hopper by adding pigments, stabilizers, plasticizers, fillers, and the like to plastics.

It has a resin injector connected to the inlet, and heats it by electric heat, high pressure steam, etc., and heats the plastic appropriately depending on the material to about 170 ° C for styrene resin or polyvinyl chloride and about 200 ° C for polypropylene. Make it.

This is injected into the mold through the inlet through a piston. When it flows to the corner of the mold, the piston returns and the mold is divided into upper and lower molds, and the hard plastic is taken out from the mold.

FIG. 1 is a schematic view showing an injection molding system for such an injection molding. In the general injection molding system, a product cavity 5 and 7 is formed between an upper mold 1 and a lower mold 3, and the product Corresponding to the cavities 5 and 7, a plurality of gate valves G1 and G2 are provided to the molds 1 and 3 on the resin inlets 13 and 15 through which resin is supplied from the external resin injectors 9 and 11. Is placed.

In addition, each of the gate valves G1 and G2 is connected to an external air tank 17 and each air line 19 so as to receive an air pressure that is an operating pressure for operating the gate valves G1 and G2. The solenoids are respectively provided on the air line 19. Valves 21, 23, and 25 are configured, each of the solenoid valves 21, 23, and 25 being electrically connected to a controller 29 including a timer 27 to turn on / off from the controller 29. Each gate valve G1 and G2 can be controlled by a control signal.

In this injection molding system, as shown in FIG. 3, the control method of the injection molding gate valve first inputs information on the product cavity 5, 7 to be injection molded into the controller 29. In operation S100, when the first and second resin injectors 9 and 11 are operated (S200), the controller 29 determines whether there is a resin supply signal from the first and second resin injectors 9 and 11 (S300). .

In this case, when it is determined that the resin supply signal is input, the controller 29 outputs a control signal to simultaneously open the gate valves G1 and G2 (S400), whereby the resin is a gate valve. At the same time as it is introduced into the product cavity (5,7) via (G1, G2). The timer 27 operates to count the supply time (S500).

During this operation, the controller 29 determines whether the counting time reaches the set time from the timer 27, and when the set time is reached (S600), outputs a simultaneous close signal to each of the gate valves G1 and G2. (S700) is to block the supply of resin into the product cavity (5,7).

However, when the gate valve is controlled by the conventional injection valve control method for injection molding as described above, in the case of producing a product made of different resin materials for each of the product cavities 5 and 7, each boundary portion P ), There is a problem that the boundary due to the dissimilar resin material is unclear and causes product defects.

Therefore, the present invention was created in order to solve the above problems, and an object of the present invention is to adjust the resin supply timing through the sequential control of the gate valve to injection molding a product made of at least two resin materials. The present invention relates to a gate valve control method for injection molding in which the boundary portion (P) can be distinguished well.

1 is a block diagram of an injection molding system to which the present invention is applied.

2 is a flowchart illustrating a method for controlling a gate valve for injection molding according to the present invention.

Figure 3 is a flow chart for illustrating a gate valve control method for injection molding according to the prior art.

Gate valve control method for injection molding according to the present invention for achieving the object as described above is formed between the upper mold and the lower mold product cavity is formed to be filled with a different resin material, the upper mold and the corresponding product cavity In the lower mold, a plurality of gate valves are arranged on the resin inlets through which the different resins are supplied from the first and second resin injectors, and each gate valve is connected to an external air tank and each air line to receive the working pressure. Each solenoid valve is configured on the air line, and each solenoid valve is electrically connected to a controller including a timer to control each gate valve by an on / off control signal from the controller. In the injection molding gate valve control method for controlling the injection molding system,

A first step of inputting information of a product cavity in which the heterogeneous resin material is to be filled into the controller; A second step of supplying heterogeneous resin to be filled in a product cavity by operating the first and second resin injectors; A third step of operating a timer to count an operating time for operating the respective gate valves (G1, G2) to a time zone set according to the product cavity information; A fourth step of the controller receiving an operation time counted in a timer from a third step; A fifth step of determining whether the operation time received in the fourth step is an open time of each gate valve G1 and G2; If the operation time received in the fifth step is the open time of each gate valve G1, G2, an open signal is output to the corresponding solenoid valve to open the corresponding gate valve G1, G2, and the operating pressure is applied to the corresponding gate valve ( A sixth step of supplying to G1, G2); A seventh step of determining whether the operation time received from the fourth step is a close time of each gate valve (G1, G2) while the corresponding gate valves (G1, G2) are opened in the sixth step; In the seventh step, if the received operation time is the close time of the gate valves G1 and G2, a close signal is output to the solenoid valve to close the gate valves G1 and G2, so that the corresponding gate valve G1, G8) includes an eighth step of shutting off the working pressure.

Hereinafter, the preferred cylinder head casting method of the present invention will be described in detail with reference to the accompanying drawings.

1 is a configuration diagram of an injection molding system to which the present invention is applied, and FIG. 2 is a flowchart illustrating a method for controlling a gate valve for injection molding according to the present invention. First, a configuration of an injection molding system to which the present invention is applied will be described. , Between the upper mold 1 and the lower mold 3, product cavities 5 and 7 to be filled with different kinds of resin materials are formed, and a plurality of molds 1 and 3 correspond to the product cavities 5 and 7. Gate valves G1 and G2 are disposed on the resin inlets 13 and 15 to which resin is supplied from external first and second resin injectors 9 and 11.

In addition, each of the gate valves G1 and G2 is connected to an external air tank 17 and each air line 19 so as to receive an air pressure that is an operating pressure for operating the gate valves G1 and G2. The solenoids are respectively provided on the air line 19. Valves 21, 23, and 25 are configured, each of the solenoid valves 21, 23, and 25 being electrically connected to a controller 29 including a timer 27 to turn on / off from the controller 29. Each gate valve G1 and G2 can be controlled by a control signal.

In the injection molding system, as shown in FIG. 2, the control method of the injection molding gate valve first inputs information of product cavities 5 and 7 to be filled with different resin materials in the controller 29. (S10)

At this time, the first resin injector 9 for supplying the first resin to the product cavity 7 is connected through a first gate valve G1 and a resin inlet 13, and the product cavity ( The second resin injector 11 for supplying the second resin to 5) is connected through the second gate valve G2 and the resin inlet 15.

Then, the first and second resin injectors 9 and 11 are operated to supply heterogeneous resins to be filled in the product cavities 5 and 7. (S20)

After the step S20, the timer is operated to count an operation time for operating the respective gate valves G1 and G2 in a time zone set according to the product cavity information.

Subsequently, the controller receives an operating time counted by a timer from the step S30, and determines whether the received operating time is an open time of each gate valve G1 or G2 (S51, S52). )

At this time, in the present embodiment, the first gate valve G1 is first opened to inject the first resin into the product cavity 7, and then the second gate valve G2 is opened to open the product cavity 5. The operating time is set so that the second resin is injected into the resin.

If the operation time received in the step (S51, S52) is the open time of each gate valve (G1, G2), the open signal to the corresponding solenoid valve (21 → 23, 25) to open the corresponding gate valve (G1 → G2) The output pressure is sequentially supplied to the corresponding gate valves G1 and G2. (S61, S62)

In this state, when the corresponding gate valves G1 and G2 are open, it is determined whether the operation time received from the step S40 is a closing time of each gate valve G1 and G2. (S71 and S72)

If the received operation time in the step (S71, S72) is the closing time of the gate valve (G1, G2), close to the solenoid valve (21, 23, 25) to close the gate valve (G1, G2) The injection molding of the product is terminated by outputting a signal to cut the working pressure to the corresponding gate valves G1 and G2.

In the description of the operation as described above, the open operation time and the closing operation time of the first and second gate valves (G1, G2) may be set by the cavity information of the product, the set time may vary. After the closing operation point of the one-gate valve G1, the opening operation point of the second gate valve G2 does not have to be continued.

According to the gate valve control method for injection molding according to the present invention as described above, when injection molding a product made of at least two resin materials by adjusting the resin supply time through the sequential control of the gate valve, the boundary portion (P) ), It is possible to get a good price of an injection product.

Claims (1)

A product cavity is formed between the upper mold and the lower mold to be filled with different resin materials, and a plurality of gate valves are supplied to the upper mold and the lower mold from the first and second resin injectors, respectively, to correspond to the product cavity. It is disposed on the resin inlet, and each gate valve is connected to the external air tank and each air line so that the working pressure can be supplied, the solenoid valve is configured on the air line, each of the solenoid valve is a timer In the injection molding gate valve control method for controlling the injection molding system is electrically connected to a controller including a control configured to control the respective gate valves by the on / off control signal from the controller, A first step of inputting information of a product cavity in which the heterogeneous resin material is to be filled into the controller; A second step of supplying heterogeneous resin to be filled in the product cavity by operating the first and second resin injectors; A third step of operating a timer to count an operating time for operating the respective gate valves (G1, G2) to a time zone set according to the product cavity information; A fourth step of the controller receiving an operation time counted in a timer from a third step; A fifth step of determining whether the operation time received in the fourth step is an open time of each gate valve G1 and G2; If the operation time received in the fifth step is the open time of each gate valve G1, G2, an open signal is output to the corresponding solenoid valve to open the corresponding gate valve G1, G2, and the operating pressure is applied to the corresponding gate valve ( A sixth step of supplying to G1, G2); A seventh step of determining whether the operation time received from the fourth step is a close time of each gate valve (G1, G2) while the corresponding gate valves (G1, G2) are opened in the sixth step; In the seventh step, if the received operation time is the close time of the gate valves G1 and G2, a close signal is output to the solenoid valve to close the gate valves G1 and G2, so that the corresponding gate valve G1, An eighth step of shutting off the operating pressure at G2); Gate valve control method for injection molding comprising a.