KR100679454B1 - Elastic valve system for injection molding - Google Patents

Abstract

The present invention discloses an elastic valve device for an injection molding machine.

The elastic valve device for injection molding machine of the present invention is a member of a length member having a tubular shape processed to be a small diameter while the outer diameter of the lower end portion in the valve device for injection molding machine, the upper end protrudes to the upper side of the manifold and the upper surface The elastic adjustment cap is screwed in to selectively change the internal space, and the lower end is located on the diameter reduction part where the diameter of the resin channel is reduced, and the pressure at which the upper part of the valve pin is slide-inserted to be moved upward by the resin pressure therein. A control pin, and a spring provided between the valve pin and the elastic control cap to selectively block the gate by applying an elastic force to the valve pin, and by lifting the pressure control pin, screwed to the upper outer periphery of the pressure control pin While preventing the movement in the vertical direction to the manifold is configured to include a control means that is capable of rotation. The injection valve elastic valve device and the resin pressure of the nozzle can be precisely controlled as described above, so that the processing error of each nozzle and the processing error of the branched resin channel of the manifold in the injection molding machine employing the multi-type nozzle It is possible to uniformly control by compensating for the uneven injection amount by the.

Hot Runner, Manifold, Spring, Nozzle, Valve Pin

Description

Elastic valve system for injection molding

1 is a cross-sectional view showing a valve device for an injection molding machine according to the prior art,

2 and 3 is a cross-sectional view showing a gate opening state of the elastic valve device for injection molding machine according to the present invention,

4 is a cross-sectional view showing a state of changing the diameter of the resin channel in the elastic valve device for injection molding machine of FIG.

5 is a cross-sectional view showing a state in which the elastic control cap retracted in the elastic valve device for injection molding machine of FIG.

<Explanation of symbols for the main parts of the drawings>

10: manifold 10b: diameter reduction part

20: nozzle 20a: resin channel

30: pressure control pin 35: elastic control cap

40: spring 50: adjusting means

51 support body 52 rotating body

The present invention relates to an elastic valve device for an injection molding machine that controls the lift of the valve pin using the resin pressure and the spring, and more specifically, to precisely control the injection amount while controlling the nozzle opening timing by adjusting the spring elasticity. An elastic valve device for an injection molding machine that enables mass production of high quality molded products.

In general, an injection molding machine for molding a plastic product injects a water support material into a manifold from a mold cylinder in which resin is melted, and the injected resin is distributed evenly along a resin channel branched in the manifold to be coupled to the bottom of the manifold. It is a device that is supplied to each of the at least one nozzle and injected into the cavity of the mold, which is a product forming mold.

The injection molding machine is configured to open and close the gate by the lifting and lowering operation of the valve pin, and in the case of molding several pieces at a time according to the quantity of molded products, a manifold type that receives resin through a manifold is used, and a single product is produced. Single type is used when

1 is a cross-sectional view showing a valve device for an injection molding machine for raising and lowering the valve pin by using a high-pressure air as the operating pressure according to the prior art.

As shown in the related art, the conventional injection molding machine valve device includes a driving unit 100 and a valve device 200, and uses high pressure air as a driving source for the lifting operation of the valve pin 210.

That is, the driving unit 100 is formed with a plurality of air channels (110, 120) which is a pipe for supplying and discharging air of high pressure from the outside, and selectively through the plurality of air channels (110, 120) The piston 140 in the cylinder 130 moves up and down by the high pressure air flowing in. At this time, the lower end of the piston 130 has a structure in which the valve pin 210 is connected and interlocked.

In addition, the valve pin 210 is configured to selectively block or open a gate that forms the front end of the nozzle 220 by being elevated in conjunction with the piston 130.

On the other hand, the valve device 200 includes a nozzle 220 to which the heater is wound to prevent the solidification of the resin by forming an outer body, the valve pin 210 in the nozzle 220 in the vertical direction It is a structure that is installed to achieve lifting. Here, the nozzle 220 is a resin channel 230 is formed with a predetermined gap around the valve pin 210, both ends of the resin channel 230, the gate of the nozzle and the resin channel of the manifold 300 Each structure is connected to the 310.

In the valve device for injection molding machine configured as described above, when the high pressure working pressure is selectively supplied through the air channels 110 and 120, the piston 140 moves up or down, and at the same time, the valve pin 210 is interlocked with each other. The lifting operation is performed. Therefore, as the piston 140 is elevated, the gate of the nozzle is opened or shut off, and as a result, the resin supplied through the manifold 300 is supplied into the mold or blocked through the gate.

In summary, the valve gate device for the injection molding machine to operate the air pressure according to the prior art to raise the piston 140 by selectively supplying the high pressure air into the cylinder 130 through the corresponding air channels (110, 120), At this time, in conjunction with the piston 140, the valve pin 210 opens and closes the gate of the nozzle.

However, since the valve device according to the related art configured as described above uses high pressure air as an operation source for elevating the valve pin, it is necessary to adopt an airtight structure to prevent air leakage and a large pneumatic device for supplying the working pressure. As it requires a compressor, the structure is complicated by its volume, which is not only limited to the installation space but also has a disadvantage of extremely poor maintenance and management.

In addition, when applied to a multi-cavity mold having a plurality of nozzles, due to the dimensional dispersion of each nozzle, a deviation occurs in the injection amount of each nozzle, there was a problem that it is difficult to mass-produce a molded article having a uniform quality.

In order to solve such a problem, the applicant has applied for utility model registration No. 2002-09883 (Registration No. 0280604, registration decision), Utility Model Registration Application No. 2002-09884 (Registration No. 0280605, Registration Maintenance Decision), utility Application for registration of utility model No. 2002-09885 (registration No. 0280606, registration maintenance decision), application for utility model registration No. 2002-19175 (registration No. 0290456, registration maintenance decision), application for utility model registration No. 2003-0034932 (registration) No. 0341515 registration maintenance decision, Utility Model Registration Application No. 2003-0038360 (Registration No. 0344137 registration maintenance decision) has proposed a valve device for operating the valve pin in the vertical direction by the power source.

Looking at the configuration of these valve device roughly, the valve body and the drive means is largely composed, the valve body is a resin flow path for injecting the resin into the mold through the gate provided at the tip is formed in general Take the valve structure. As the driving means, a forward / reverse motor or an actuator for raising and lowering the valve pin by power supply is used.

In this way, the applicant's prior application of the valve device allows the size of the valve device to be reduced in size by employing a forward / reverse motor or an actuator as a driving source, thereby increasing the degree of freedom in mold design and increasing the amount of valve pin movement. Quick and precise control is possible.

However, since the present inventors have applied for a high-cost electronic device, the valve device is suitable for injection of precision molded products, but there is an economical inefficiency in injection of a simple molded product that does not require precision molding.

In addition, even when the resin channels of the manifold and the nozzle are precisely molded without dimensional dispersion, the manifold and the nozzle of the metal material are exposed for a long time due to the high temperature heat generated during the injection process, causing deformation, resulting in uneven injection amount. There was a problem of reworking.

On the other hand, the present applicant has filed a "injection molding machine with an injection pressure control device" to Patent Application No. 10-2005-0002522 in order to solve the above problems.

The injection molding machine equipped with the injection pressure adjusting device, which the applicant has previously applied, allows to uniformly control a plurality of nozzle injection amounts through a configuration of additionally mounting a resin pressure adjusting means capable of variably adjusting the diameter on the resin channel.

However, the injection molding machine equipped with the injection pressure adjusting device, which has been filed by the applicant, has a disadvantage in that there is a limit in compensating the injection amount according to the processing error when the processing error of each resin channel of the manifold and the nozzle is large. There was a disadvantage that it is difficult to precisely control the opening and closing of the.

In addition, since a pneumatic cylinder is employed as a driving source for elevating the valve pin, there is a disadvantage in that the workability and serviceability are poor due to its large volume and complexity.

The present invention has been made to solve the above problems, an object of the present invention is to operate the valve pin using the injection pressure and the spring without requiring a separate drive source, and to variably adjust the elastic force of the spring nozzle An elastic valve device for an injection molding machine that can easily control the opening and closing speed of the.

Another object of the present invention is to equally precisely control the injection amount of each nozzle in the multi-nozzle to compensate for the molding quality unevenness according to the processing deviation of the manifold and the nozzle to improve the quality of the product and the processing of the manifold and the nozzle The present invention provides an elastic valve device for an injection molding machine that can significantly increase the degree of freedom and reduce manufacturing costs.

An elastic valve device for an injection molding machine according to the present invention for realizing the above object comprises: a manifold having a branched resin channel for injecting a water support material into a mold; In the valve device for an injection molding machine, the resin channel is connected to the gate of the front end portion, the valve device comprising a nozzle having a valve pin in the center to open and close the gate by a lifting operation,

A member of a length member having a tubular shape processed to become a small diameter while the outer diameter of the lower end proceeds downward, the upper end protrudes to the upper side of the manifold, the upper surface is screwed with an elastic control cap to selectively vary the internal space, the lower end The pressure adjusting pin is located on the diameter reducing portion in which the diameter of the resin channel is reduced, and the upper portion of the valve pin is slide-inserted to move upward by the resin pressure therein; A spring provided between the valve pin and the elastic control cap to selectively block the gate by applying an elastic force to the valve pin; By elevating the pressure control pin, the screw is coupled to the upper outer periphery of the pressure control pin to prevent movement in the vertical direction to the manifold, characterized in that it comprises a control means that is rotatably provided.

As a preferred feature of the invention, the valve pin is formed at least one guide groove in the vertical direction in proportion to the gate opening and closing movement distance on the outer periphery of the upper end, so as to limit the opening and closing position of the gate, corresponding to the guide groove The upper inner circumferential surface of the pressure control pin is to protrude the stopper for limiting the moving distance of the valve pin.

As another preferable feature of the present invention, the adjusting means is a support fixedly installed on the manifold at intervals with the upper outer circumference of the pressure control pin, and the lower inner circumferential surface is rotatably fitted to the outer circumferential surface of the support and the upper portion is It extends upward and is configured to include a rotating body screwed to the upper outer periphery of the valve pin.

The features and advantages of the present invention will become more apparent from the following detailed description based on the accompanying drawings. Prior to this, the terms or words used in the present specification and claims are consistent with the technical spirit of the present invention based on the principle that the inventor can appropriately define the concept of the term in order to explain the invention in the best way. It must be interpreted as meaning and concept.

Hereinafter, a preferred embodiment of a valve device for an injection molding machine according to the present invention will be described in detail with reference to the accompanying drawings.

2 and 3 are cross-sectional views showing a gate opening state of the elastic valve device for injection molding machine according to the present invention, Figure 4 is a cross-sectional view showing a state of changing the diameter of the resin channel in the elastic valve device for injection molding machine of FIG. . And, Figure 5 is a cross-sectional view showing a state in which the elastic control cap retracted in the elastic valve device for injection molding machine of FIG.

As shown in the figure, the elastic valve device for injection molding machine of the present invention, the manifold (10) in which the resin channel (10a) is divided into several branches so that the resin can be moved therein to inject the water support material into the mold. And a valve pin installed on the lower surface of the manifold 10 to receive resin and inject the resin into the mold. The valve pin for selectively opening and closing the inlet (hereinafter referred to as a 'gate') of the nozzle 20 ( 21).

Here, the nozzle 20 is a member of the tubular length member tapered in a form in which the lower end portion, that is, the portion where the gate is located, is reduced in diameter while traveling downward, and at the inner center of the manifold 10 A resin channel 20a is connected to the resin channel 10a to receive resin. Here, although not shown, the gate of the nozzle 20 is connected to one end of a mold for molding a molded article, and the nozzle 20 is for preventing the solidification of the resin passing through the resin channel 20a to the outer circumferential surface thereof. The heater wire is wound.

The nozzle 20 is provided with a valve pin 21 having a smaller diameter than the inner diameter of the resin channel 20a formed at the center thereof, and the valve pin 21 is lifted to selectively open and close the gate.

The configuration as described above is similar to the configuration of the valve device for injection molding machines. However, in the present invention, the valve pin 21 is selectively lifted by using the resin pressure and the spring 40 without providing a separate driving source, and the inside diameter of the resin channel is varied so that a large number of dies in the cavity die can be obtained. The nozzle 20 is to be able to uniformly adjust the injection amount.

To this end, the present invention, as shown in Figures 2 and 3, the upper end of the valve pin 21 to slide the valve pin 21 is inserted into the pressure adjustment pin to the position change in the vertical direction by the screw adjustment method 30, a spring 40 for elastically pressing upward from the valve pin 21 to open the gate, and an adjusting means 50 for transmitting the operator's operating force to the pressure adjusting pin 30. Configuration.

The pressure regulating pin 30 is a member of a length member having a tubular shape, the upper end of which protrudes upward of the manifold 10 and the lower end of which is located on the resin channel 10a.

Here, the upper end of the pressure adjusting pin 30 is screwed to the outer periphery is coupled to the screw fastened to the control means 50 to be described later to be interlocked, the open top surface as shown in the drawing elastic control cap 35 It is a structure that is screwed to be able to variably adjust the size of the upper internal space of the pressure control pin 30 by moving in the vertical direction by the screw adjustment method.

In addition, the lower end of the pressure control pin 30 is tapered to have a small diameter while the outer diameter is downward, and the tapered lower end is positioned on a diameter reduction portion 10b in which the diameter of the resin channel 10a is reduced. . Here, the diameter reducing portion 10b of the resin channel is tapered to form a narrower diameter as it proceeds downward as shown in the drawing so that the diameter can be reduced when the pressure adjusting pin 30 moves downward. The minimum diameter of the reduction part 10b is the same size as the diameter of the resin channel 20a of the nozzle 20.

On the other hand, the upper end of the valve pin 21 is inserted into the lower end of the pressure control pin 30, the inner diameter of the pressure control pin 30 is compared with the size of the resin channel inner diameter of the nozzle 20 It is processed greatly. That is, the upper end of the valve pin 21 slide-inserted into the lower portion of the pressure control pin 30 forms an expanded portion 21a having an expanded diameter, and as shown in the drawing, the resin pressure acts on the lower surface thereof. Will move upward.

The pressure regulating pin 30 configured as described above is provided with a spring 40 in an upper inner space thereof, and is elevated in a vertical direction along the valve pin 21 in association with an adjusting means 50 that receives an operator's operation force.

The spring 40 is provided in the space between the valve pin 21 and the elastic control cap 35 serves to block the gate by lowering by applying an elastic pressing force to the valve pin 21. The spring 40 is to maintain the gate of the nozzle 20 is blocked when the resin pressure is not applied to the nozzle 20, a conventional coil spring may be used.

On the other hand, the pressure of the spring 40 is within a range in which the gate is not opened by the back pressure when the resin is plasticized while having a pressure smaller than the resin pressure acting on the cylinder (not shown) for supplying the molten resin. Low pressure is preferred.

The spring 40 configured as described above lowers the valve pin 21 to block the gate in a state in which the elastic pressure is applied to the valve pin 21 so that the resin pressure does not act on the nozzle 20. The spring 40 is the elastic force is adjusted by moving the elastic control cap 35 in the vertical direction by the screw adjustment method, through which the magnitude of the elastic pressing force applied to the valve pin 21 is changed. Therefore, when the resin pressure is fluctuated or the elastic force of the spring 40 is changed, the elastic modulus of the spring 40 may be constantly adjusted by using the elastic adjustment cap 35.

The adjusting means 50 is a member for transmitting the operating force of the operator to move the above-mentioned pressure adjusting pin 30 in the vertical direction, and is largely composed of the support 51 and the rotating body 52, the rotating body ( The bearing may be provided on the contact surface so that the 52 may rotate smoothly with respect to the support 51.

Here, the support 51 is a member having an annular shape that is fixed to the manifold 10 at intervals at the outer circumference of the upper end of the pressure adjusting pin 30, the bottom surface of which is welded on the manifold 10 or It is fixedly installed through the fitting structure.

In addition, the rotor 52 is rotatably supported by the lower end of the support 51 and the upper portion of the structure is the inner circumferential surface is screwed to the upper outer periphery of the valve pin 21.

Here, the rotating body 52 and the support 51 is provided with a structure in which the projections and grooves are formed to correspond to the lower inner circumferential surface of the rotating body 52 and the outer circumferential surface of the support 51, respectively, and are fitted to each other. 52 is provided to be rotated in the rotational direction while the movement in the vertical direction relative to the support 51.

When the adjustment means 50 is configured in this way or rotates in one direction or in reverse direction, the pressure adjusting pin 30 moves in the vertical direction. For example, when the rotating body 52 of the adjusting means 50 rotates in one direction as shown in FIG. 3, the pressure adjusting pin 30 moves downward in association with the diameter of the diameter reducing part 10b as shown in FIG. 4. As a result, the amount of resin passing through the nozzle 20 is adjusted. Here, when the pressure control pin 30 is moved, the elastic force of the spring 40 is changed accordingly. The elastic force change of the spring 40 may be adjusted by using the elastic adjustment cap 35.

On the other hand, the present invention is a guide groove 22 in the valve pin 21 and the pressure control pin 30, respectively, so as to limit the moving distance, that is, the opening and closing position of the gate when the valve pin 21 is moved in the vertical direction. And a stopper 32.

That is, the valve pin 21 has a structure in which at least one guide groove 22 having a distance proportional to the opening and closing movement distance of the gate is formed in the vertical direction on the outer circumference of the upper end of the diameter, and the pressure regulating pin 30 ) Is a structure in which the stopper 32 is inserted into the guide groove 22 into the inner circumferential surface of the upper end of the valve pin 21 so as to protrude from the end of the groove.

Meanwhile, in the present invention, the lower end of the pressure adjusting pin is provided on the resin channel 10a of the manifold connected in series with the resin channel 20a of the nozzle 20. However, the present invention is not limited thereto. Without having a feature that can vary the size of the inner diameter of the resin channel may be carried out by having the lower end of the pressure control pin in various positions. For example, the lower end of the pressure regulating pin may be formed to extend to a position close to the gate of the nozzle, wherein the diameter reduction portion is formed to correspond to the injection channel of the nozzle in which the end of the pressure regulating pin is located.

Referring to the operation of the elastic valve device for injection molding machine of the present invention configured as described above are as follows.

First, in the state where resin is not supplied from the cylinder through the manifold 10 as shown in FIG. 2, since the resin pressure does not act in the nozzle 20, the valve pin 21 is lowered by the spring 40 to open the gate. Will be blocked.

In this state, when the resin is supplied to the nozzle 20 and the resin pressure acts, the resin pressure acts upward to the upper lower surface of the valve pin 21 as shown in FIG. 3 to open the gate. Since the spring 40 has a smaller pressure than the resin pressure, the spring 40 is compressed when the resin pressure is applied.

Subsequently, when the injection is terminated and the resin is not supplied to the nozzle 20, the resin pressure acting on the nozzle 20 is released, so that the spring 40 is elastically returned and the valve pin 21 is lowered as shown in FIG. 2. State, that is, a state in which the gate is blocked.

In this case, when the elastic control cap 35 is rotated in one direction or the reverse direction, the elastic force of the spring 40 may be adjusted by moving upward or downward based on the pressure adjusting pin 30. As such, when the elastic force of the spring 40 is adjusted, the size of the elastic pressing force applied to the valve pin 21 can be adjusted. As a result, the reaction speed and the gate opening and closing time of the valve pin 21 according to the resin pressure can be precisely controlled. It can be adjusted.

On the other hand, in the case of adjusting the injection amount of the nozzle 20 by changing the diameter of the resin channel, by rotating the rotary body 52 of the adjusting means 50 by a predetermined angle, the rotary body 52 and the screw adjustment method The pressure control pin 30 is coupled to move up or down while rotating.

At this time, the lower end of the pressure control pin 30 is located on the diameter reducing portion (10b), so when moving downwards is located in the form of reducing the interval with the diameter reducing portion (10b) as shown in Figure 4 and consequently passed through the resin In the case of reducing the amount and moving upward, the amount of resin passing is increased by expanding the gap with the diameter reducing portion 10b.

The elastic valve device for the injection molding machine configured as described above has a manifold 10 due to a high temperature heat generated in the injection channel or a process error in the resin channel of a specific nozzle among the branched resin channels or the plurality of nozzles 20. And when the nozzles 20 are deformed and the injection amounts of the nozzles 20 are not the same, the injection volume of each nozzle 20 is equally adjusted by precisely adjusting the resin passage amount on the resin channel by using the pressure adjusting pin 30. Can be controlled.

In addition, even when the resin pressure is changed or the elastic force of the spring 40 is reduced, the elastic force of the spring 40 is simply adjusted by using the elastic adjustment cap 35 to optimally adjust the response condition of the valve pin 21. Can be maintained.

It is apparent to those skilled in the art that the present invention is not limited to the described embodiments, and that various modifications and changes can be made without departing from the spirit and scope of the present invention. Therefore, such modifications or variations will have to belong to the claims of the present invention.

The injection valve elastic valve device configured and operated as described above has a structure in which the inlet of the nozzle, that is, the gate is blocked by a spring, and when the injection is started in this state, the gate is opened by the resin pressure and the injection is made. It does not need to have a simple structure and good maintainability.

In particular, the resin pressure of the nozzle can be precisely controlled by simply adjusting the pressure adjusting pin by lifting the adjustment means, so that the injection error of the multi-type nozzle and the branched resin channel of the manifold are different. Non-uniform injection amount caused by processing error can be compensated and uniformly adjusted.

Therefore, it is possible to greatly increase the degree of freedom of processing of the nozzle and manifold, thereby reducing the production cost, enabling mass production of molded articles having a uniform quality, and providing an advantage of significantly increasing the reliability of the device.

In addition, the response speed of the valve pin can be varied by variably adjusting the elastic force of the spring. Therefore, the injection speed can be adjusted according to the size and material of the molded part. Therefore, it is useful to improve the quality and productivity of the molded part. to provide.

Claims (3)

The manifold is formed with a branched resin channel for injecting the support material into the mold, and the resin channel coupled to the lower surface of the manifold is connected to the gate of the front end and the gate is opened and closed at the center by a lifting operation. In the valve device for injection molding machine consisting of a nozzle having a valve pin, A member of a length member having a tubular shape tapered to a small diameter as the outer diameter of the lower end proceeds downward, the upper end protrudes to the upper side of the manifold, and the upper surface of the lower end portion is selectively variable by varying the internal space, the lower end The pressure adjusting pin is located on the diameter reducing portion in which the diameter of the resin channel is reduced, and the upper portion of the valve pin is slide-inserted to move upward by the resin pressure therein; A spring provided between the valve pin and the elastic control cap to selectively block the gate by applying an elastic force to the valve pin; By raising and lowering the pressure adjusting pin, screwing is coupled to the upper outer circumference of the pressure adjusting pin to prevent movement in the vertical direction to the manifold and the rotation means is provided; Elastic valve device for injection molding machine comprising a. According to claim 1, wherein the valve pin is formed at least one guide groove in the vertical direction in the vertical direction on the outer periphery of the upper end portion so as to limit the opening and closing position of the gate, the pressure control corresponding to the guide groove The upper inner circumferential surface of the pin is an elastic valve device for injection molding machine, characterized in that the stopper protruding to limit the moving distance of the valve pin. According to claim 1 or 2, wherein the adjusting means is a support that is fixed on the manifold at intervals with the outer peripheral edge of the pressure control pin and the lower inner peripheral surface rotatably fitted to the outer peripheral surface of the support An upper portion of the elastic valve device for injection molding machine characterized in that it comprises a rotating body which is screwed to the upper outer periphery of the upper end of the valve pin.

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