JP2023175183A - Die unit and injection molding machine - Google Patents

Abstract

To provide a die unit and an injection molding machine that have a simple configuration, perform molding work after surely returning a placed core to a die, and do not damage the die.SOLUTION: An injection molding machine 10 has control means 80 that controls operation of the injection molding machine and is connected to detection means and negative pressure means, wherein the control means 80 closes a first air passage 52a and a second air passage 53f when the placing core 60 is located in a recess part when molding of a molded product F is completed and a movable die 52 is separated from a fixed die 51, and enables the movable die 52 to operate when the detection means detects a predetermined air pressure.SELECTED DRAWING: Figure 8

Description

The present invention relates to a mold unit and an injection molding machine using the same, which performs molding using an undercut core.

Patent Document 1 describes a simple injection mold, and according to this, the simple injection mold is composed of a fixed side mold, a movable side mold, and a placing core, and the fixed side mold and The molded product was formed by filling a closed mold space formed by a movable mold and a placing core with molten resin, and cooling and solidifying the resin.

Japanese Patent Application Publication No. 2001-205679

However, in the above-mentioned simple molding die, when ejecting the molded product, the placing core is taken out of the mold together with the molded product by the ejector pin, and is manually returned to the mold.

In order to confirm whether the placed core has been returned reliably, it is possible to compare the reference image with the real-time image, but the judgment accuracy may be affected due to the difference in light exposure due to the time difference between the reference image and the real-time image. There was a risk that it would become lower.

It is also conceivable to use a touch sensor, but the thermal expansion of the mold and placed core would lower the accuracy of the judgment, and the configuration would be complicated because wiring would have to be provided.

From the above, if a molding operation is performed before the placed core has returned completely to the mold, there is a risk that it will interfere with the mold during clamping and damage the mold.

The present invention provides a mold unit and an injection molding machine that have a simple configuration, perform molding work after reliably returning the placed core to the mold, and do not damage the mold. .

In the invention according to claim 1, a fixed side mold, a movable side mold that approaches and moves away from the fixed side mold, and a movable side mold that is arranged on the fixed side mold and/or the movable side mold. A mold unit used in an injection molding machine that molds a molded product by injecting molten resin into a product molding section formed by a placing core,
The mold unit includes the fixed mold, the movable mold, and the placing core,
The fixed side mold and/or the movable side mold in which the placed core is arranged include:
A recess opening facing the product molding section is provided, and a first air passage through which air can flow so as to communicate with the recess, and air can flow through a position different from the first air passage. a second air passage;
The placing core is formed to be movable within the recess, and is capable of closing the first air passage and the second air passage at the same time,
The second air passage is connected in this order to a detection means for detecting air pressure in the second air passage, and a negative pressure means for bringing the second air passage into a negative pressure state,
In the assembled state, the detection means is connected to a control means for controlling the operation of the injection molding machine,
When the molding of the molded product is completed and the movable mold is separated from the fixed mold, the placing core is located in the recess and the first air passage and the second air When the passage is closed and the detection means detects that the air pressure is at a predetermined level, a signal is output to the control means to enable the movable mold.

According to this, the first air passage and the second air passage are closed by the placing core, and the detection means detects that the air pressure is at a predetermined level, so that the placing core can be securely placed with a simple configuration. After returning to the mold, a molding operation can be performed, and a mold unit that does not damage the mold can be obtained.

Further, an ejector capable of sending out the placed core toward the product forming section can be arranged in the first air passage.

According to this, the first air passage also functions as a passage in which the ejector is arranged, leading to a simple configuration.

Further, in the invention according to claim 3, a fixed side mold, a movable side mold that approaches and moves away from the fixed side mold, and the fixed side mold and/or the movable side mold. An injection molding machine that molds a molded product by injecting molten resin into a product molding section formed by a placed core,
The fixed side mold and/or the movable side mold in which the placing core is placed are provided with a recess that opens to face the product molding section, and communicates with the recess. , a first air passage through which air can flow, and a second air passage through which air can flow are arranged at a position different from the first air passage,
The placing core is formed to be movable within the recess, and is capable of closing the first air passage and the second air passage at the same time,
The second air passage is connected in this order to a detection means for detecting air pressure in the second air passage, and a negative pressure means for bringing the second air passage into a negative pressure state,
comprising a control means that controls the operation of the injection molding machine and is connected to the detection means,
The control means may be arranged such that when the molding of the molded product is completed and the movable mold is separated from the fixed mold, the placing core is located in the recess and the first air passage is controlled. Then, when the second air passage is closed and the detection means detects that the air pressure is at a predetermined level, the movable mold is made operable.

According to this, it is possible to provide an injection molding machine that exhibits the effects of the mold unit according to the first aspect.

Further, an ejector that can send out the placed core toward the product forming section is disposed in the first air passage.

According to this, it is possible to provide an injection molding machine that exhibits the effects of the mold unit according to the second aspect.

Further, the negative pressure means and the detection means are disposed outside the fixed mold and/or the movable mold in which the placing core is disposed.

According to this, maintenance can be performed by removing the negative pressure means and the detection means from the stationary side mold and/or the movable side mold, so maintenance management can be facilitated.

Further, a filter is disposed between the second air passage and the detection means.

According to this, the filter can prevent problems caused by dirt on the negative pressure means and the detection means.

1 is a schematic side view of an injection molding machine according to an embodiment of the present invention. It is a block explanatory diagram of the main part of the same embodiment. FIG. 2 is an explanatory diagram showing the operating state of main parts of the injection molding machine of the same embodiment. FIG. 4 is an explanatory diagram showing an operation state continued from FIG. 3; FIG. 5 is an explanatory diagram showing an operation state continued from FIG. 4; FIG. 6 is an explanatory diagram showing an operation state continued from FIG. 5; FIG. 7 is an explanatory diagram showing an operation state continued from FIG. 6; FIG. 8 is an explanatory diagram showing an operation state continued from FIG. 7; It is an explanatory view showing a modification in the case where a core is placed in a stationary mold.

An embodiment of an injection molding machine according to the present invention will be described based on the drawings. In the following description, F is the front, B is the back, R is the right, L is the left, U is the top, and D is the bottom of the arrows in each drawing.

As shown in FIG. 1, the injection molding machine 10 includes an injection device 20, a mold clamping device 30, and a mold 50.

In the injection device 20 , a screw 22 is disposed within a cylindrical heating cylinder 21 , and the screw 22 is rotated by a hydraulic motor 23 . A heater 24 for melting the synthetic resin W is disposed on the outer peripheral surface of the heating cylinder 21. A hopper 25 for storing synthetic resin W and supplying it into the heating cylinder 21 is provided at the front end of the heating cylinder 21 .

The injection device 20 is configured such that the molten resin W1 heated by the heater 24 and turned into a molten state from the synthetic resin W is conveyed by a screw 22 and extruded from a nozzle 26 disposed at the rear end of the heating cylinder 21. has been done.

A plurality of mold clamping devices 30 are arranged: a fixed platen 31 fixed on the bed 11, an end housing 32 arranged on the rear side of the fixed platen 31, and a plurality of mold clamping devices 30 between the fixed platen 31 and the end housing 32. A diver 33, a movable platen 34 disposed between the fixed platen 31 and the end housing 32 and formed so that the diver 33 can be inserted therethrough, and a crosshead 35 disposed between the end housing 32 and the movable platen 34. The toggle mechanism 36 has a toggle mechanism 36, a servo motor 37 as a drive device that drives the toggle mechanism 36, and a belt 39 that connects the servo motor 37 and the toggle mechanism 36 via a pulley 38.

An ejector 40 is disposed on the movable platen 34, and an ejector rod 40a can be inserted through an insertion hole 34a formed through the movable platen 34 in the front-rear direction. An ejector pin 42 is attached to the front end of the ejector rod 40a via a plate-like plate 41, so that the completed molded product F can be pushed out to the front.

In the mold clamping device 30, a movable platen 34 is movable in the front-rear direction by driving a servo motor 37.

As shown in FIGS. 3 to 8, the mold 50 includes a fixed mold 51, a movable mold 52, and a placing core 60.

The stationary side mold 51 is formed into a rectangular parallelepiped shape and is attached to the stationary platen 31. A receiving port 31 a formed in a shape corresponding to the nozzle 26 is provided at a position of the fixed plate 31 facing the nozzle 26 . A sprue flow path 51c is formed in the fixed mold 51 from the front end surface 51a toward the rear end surface 51b and communicating with the receiving port 31a.

The movable side mold 52 is formed into a rectangular parallelepiped shape and is attached to the movable platen 34.

The movable mold 52 includes a front block 53 and a rear block 54.

The front block 53 includes a bottomed hole portion 53c formed as a bottomed hole extending from the front end surface 53a to the rear end surface 53b of the front block 53, and a rear end surface 53b of the front block 53, which is smaller in width than the bottomed hole portion 53c. The ejector passage forming hole 53d is formed as a bottomed hole extending from the bottom toward the front end surface 53a, and the ejector passage forming hole 53d is formed to be smaller in width than the bottomed hole 53c and larger than the ejector passage forming hole 53d, and is formed as a bottomed hole. A communication hole portion 53e is provided that communicates the ejector passage forming hole portion 53c with the ejector passage forming hole portion 53d.

The front block 53 is provided with a second air passage 53f that is formed to extend backward from the bottomed hole 53c in parallel with the ejector passage forming hole 53d, and then extend downward. A negative pressure measurement unit 70, which will be described later, is connected to the second air passage 53f.

The rear block 54 is provided with a plate arrangement portion 54c formed as a through hole extending from the front end surface 54a of the rear block 54 to the rear end surface 54b.

The placing core 60 is formed so as to be movable in the longitudinal direction within the communication hole 53e. The placing core 60 is provided with a molding recess 60c formed as a recess extending from the outer peripheral surface toward the axis.

In this embodiment, the rear end surface 51b of the stationary mold 51, the bottomed hole 53c, the front end surface 60a and the molding recess 60c of the placing core 60, and the portion of the communicating hole 53e facing the molding recess 60c. The space surrounded by , is the product molding section 55. In other words, the communication hole portion 53e forms a part of the product molding portion 55, and the portion that does not form the product molding portion 55 functions as a recessed portion within the scope of the claims.

Further, the ejector passage forming hole 53d and the plate arrangement part 54c constitute a first air passage 52a in the claims, and the first air passage 52a includes a plate 41 and an ejector pin that constitute the ejector 40. 42 is placed. There are gaps between the ejector rod 40a and the insertion hole 34a, and between the ejector pin 42 and the ejector passage forming hole 53d, allowing air to flow therethrough.

In this embodiment, a mold unit is composed of a fixed mold 51, a movable mold 52, a placing core 60, and a negative pressure measurement unit 70.

As shown in FIG. 2, the negative pressure measurement unit 70 includes a vacuum generator 71 as a negative pressure means for bringing the second air passage 53f into a negative pressure state, and a detection means for detecting the air pressure in the second air passage 53f. The pressure switch 72 and the filter 73 are connected to the second air passage 53f.

The second air passage 53f is connected in this order to a detection means for detecting the air pressure in the second air passage 53f and a negative pressure means for bringing the second air passage 53f into a negative pressure state. Become. Further, the vacuum generator 71 is connected to an air compressor 75, and generates negative pressure by the force of air supplied from the air compressor 75. Note that the arrows in FIG. 2 indicate the flow of air.

In this embodiment, a mold unit is composed of a fixed mold 51, a movable mold 52, a placing core 60, and a negative pressure measurement unit 70.

In the injection molding machine 10, an injection device 20, a mold clamping device 30, a negative pressure measuring unit 70, etc. are connected to a control means 80 that includes a communication interface, a control circuit, and an arithmetic processing circuit.

To explain the main parts of the present invention, as shown in FIG. 2, the pressure switch 72 of the negative pressure measurement unit 70 and the mold 50 (movable mold 52) are connected to a control means 80. The vacuum generator 71 and the air compressor 75 operate independently of the control of the control means 80.

The vacuum generator 71, pressure switch 72, and air compressor 75 are set to operate at all times during the molding operation.

When the pressure switch 72 detects air pressure within a predetermined range close to vacuum, it outputs a signal to the control means 80 to enable the movable mold 52 to operate.

The manner in which the injection molding machine 10 is used will be explained.

The injection device 20 of the injection molding machine 10 moves toward the mold clamping device 30 and presses the rear end of the nozzle 26 against the receiving port 31a.

At this time, the mold clamping device 30 is in a state where the fixed mold 51 and the movable mold 52 are close to each other, as shown in FIG. In addition, when the placing core 60 closes the first air passage 52a and the second air passage 53f, the pressure switch 72 detects that the pressure switch 72 is in a predetermined range close to vacuum. 52 is in operational condition.

When a predetermined injection volume of molten resin W1 is injected from the nozzle 26, the molten resin W1 passes through the sprue channel 51c and is injected into the product molding section 55, as shown in FIG.

After injecting a predetermined injection volume of molten resin W1, the injection device 20 moves forward to prepare for the next injection operation.

When the molding of the molded product F is completed, as shown in FIG. 4, the movable mold 52 is separated from the fixed mold 51 by the drive of the servo motor 37, and then the ejector 40 is driven as shown in FIG. By moving the ejector pin 42 forward, the rear end surface 60b of the placing core 60 is pushed, and the molded product F integrated with the placing core 60 is ejected.

After the operator separates the placing core 60 and the molded product F as shown in FIG. 6, the worker returns the placing core 60 into the communication hole 53e as a recess, as shown in FIG.

In the states shown in FIGS. 5 to 7, the vacuum generator 71 and the pressure switch 72 are in an activated state, but there is a gap between the ejector pin 42 and the ejector passage forming hole 53d, and the placing core 60 does not block the first air passage 52a and the second air passage 53f, allowing air to flow into the first air passage 52a and the second air passage 53f. Therefore, the movable mold 52 does not operate because the pressure switch 72 does not detect that the pressure is within a predetermined range close to vacuum.

As shown in FIG. 8, when the placing core 60 closes the first air passage 52a and the second air passage 53f, the pressure switch 72 changes the atmospheric pressure by the vacuum generator 71, in other words, It is detected that the movable mold 52 is within a close predetermined range, and a signal is output to the control means 80 to enable the movable mold 52 to operate. As a result, the movable mold 52 becomes operable.

If the above invention is viewed as a mold unit, a fixed mold 51, a movable mold 52 that approaches and moves away from the fixed mold 51, and a placing core 60 disposed in the movable mold 52. A mold unit used in an injection molding machine that molds a molded product F by injecting molten resin W1 into a product molding section 55 formed by,
The mold unit includes a fixed mold 51, a movable mold 52, and a placing core 60,
The movable side mold 52 in which the placing core 60 is arranged includes:
A recess (communication hole 53e) that opens to face the product molding section 55 is provided, and a first air passage 52a (ejector passage forming hole 53d and plate arrangement) through which air can flow communicates with the recess. portion 54c) and a second air passage 53f through which air can circulate at a position different from the first air passage 52a,
The placing core 60 is formed to be movable within the recess (communication hole 53e) and can close the first air passage 52a and the second air passage 53f at the same time,
The second air passage 53f is connected in this order to a detection means (pressure switch 72) for detecting the air pressure in the second air passage 53f, and a negative pressure means (vacuum generator 71) for bringing the second air passage 53f into a negative pressure state. is,
In the assembled state, the detection means is connected to the control means 80 for controlling the operation of the injection molding machine 10;
When the molding of the molded product F is completed and the movable mold 52 is separated from the fixed mold 51, the placing core 60 is located in the recess, and the first air passage 52a and the second air passage 53f are closed. When the detection means detects that the air pressure is at a predetermined level, a signal is output to the control means 80 to enable the movable mold 52 to operate.

According to this, the first air passage 52a and the second air passage 53f are closed by the placing core 60, and the detecting means detects that the air pressure is at a predetermined level, so that the placing core 60 can be used with a simple configuration. The molding operation is performed after the child 60 is reliably returned to the movable mold 52, and a mold unit can be obtained without damaging the mold 50.

Further, an ejector 40 capable of feeding out the placed core 60 to the product forming section 55 side can be arranged in the first air passage 52a.

According to this, the first air passage 52a also functions as a passage in which the ejector 40 is arranged, leading to a simple configuration.

Further, if the present invention is viewed as an injection molding machine, a fixed side mold 51, a movable side mold 52 that approaches and moves away from the fixed side mold 51, and a placed core arranged in the movable side mold 52. An injection molding machine that molds a molded product F by injecting molten resin W1 into a product molding section 55 formed by 60 and
The movable mold 52 in which the placing core 60 is placed is provided with a recess (communication hole 53e) that opens to face the product molding section 55, and allows air to flow through the recess so as to communicate with the recess. A first air passage 52a and a second air passage 53f through which air can flow are arranged at a different position from the first air passage 52a,
The placing core 60 is formed to be movable within the recess (communication hole 53e) and can close the first air passage 52a and the second air passage 53f at the same time,
The second air passage 53f is connected in this order to a detection means (pressure switch 72) for detecting the air pressure in the second air passage 53f, and a negative pressure means (vacuum generator 71) for bringing the second air passage 53f into a negative pressure state. is,
It has a control means 80 that controls the operation of the injection molding machine 10 and is connected to the detection means,
The control means 80 controls the control means 80 so that when the molding of the molded product F is completed and the movable mold 52 is separated from the fixed mold 51, the placing core 60 is located in the recess and the first air passage 52a and When the second air passage 53f is closed and the detection means detects that the air pressure is at a predetermined level, the movable mold 52 is made operable.

According to this, it is possible to provide an injection molding machine that exhibits the effects of the mold unit described above.

Furthermore, an ejector 40 that can send out the placed core 60 to the product forming section 55 side is arranged in the first air passage 52a.

According to this, it is possible to provide an injection molding machine that exhibits the effects of the mold unit described above.

Further, a negative pressure means (vacuum generator 71) and a detection means (pressure switch 72) are arranged outside the movable mold 52 in which the placing core 60 is placed.

According to this, maintenance can be performed by removing the negative pressure means and the detection means from the movable mold 52, so that maintenance management can be facilitated.

Further, a filter 73 is disposed between the second air passage 53f and the detection means (pressure switch 72).

According to this, the filter 73 can prevent problems caused by dirt on the negative pressure means and the detection means.

The present invention is not limited to the above configuration. That is, various design changes are possible without departing from the gist of the present invention. Components similar to those in the first embodiment are given the same numbers, and a description of all or part of them will be omitted.

For example, a modification example in which the core is placed in the stationary mold will be described based on FIG. 9.

The fixed side mold 151 includes a bottomed hole portion 151c formed as a bottomed hole extending from the rear end surface 151b to the front end surface 151a of the fixed side mold 151, and a bottomed hole portion 151c that is smaller in width than the bottomed hole portion 151c. A communicating hole portion 151e formed as a bottomed hole extending from the bottom surface of the portion 151c toward the front end surface 151a of the stationary mold 151 is provided.

The fixed mold 151 is provided with a first air passage 151d that extends forward from the bottomed hole 151c and then extends downward.

Further, the fixed side mold 151 is provided with a second air passage 151f that is formed to extend forward from the bottomed hole portion 151c and then extend upward. A negative pressure measurement unit 70 is connected to the second air passage 151f.

With such a configuration, the mold unit and injection mold 50 can be formed without damaging the mold 50 by performing the molding operation after reliably returning the placing core 60 to the stationary mold 151 with a simple configuration. It can be a molding machine.

Although the mold clamping device 30 uses a toggle type, a direct pressure type mold clamping device can be used.

Further, the injection device 20 having the above configuration is not limited to any existing injection device, as long as it can inject the molten resin W1 into the product molding section 55.

Further, the shape of the product molding section 55 can be changed as appropriate.

Furthermore, it is also possible to reverse the unevenness of the fixed side mold 51 and the movable side mold 52.

Further, the placing core 60 can also be placed in the fixed mold 51 and the movable mold 52.

10 Injection molding machine 40 Ejector 51 Fixed side mold 52 Movable side mold 52a First air passage 53d Ejector passage forming hole section 53e Communication hole section 53f Second air passage 54c Plate arrangement section 55 Product molding section 60 Placed core 71 Vacuum Generator 72 Pressure switch 80 Control means 151 Fixed side mold 151d First air passage 151e Communication hole portion 151f Second air passage F Molded product W1 Molten resin

Claims (6)

Formed by a fixed side mold, a movable side mold that approaches and moves away from the fixed side mold, and a placing core arranged in the fixed side mold and/or the movable side mold. A mold unit used in an injection molding machine that injects molten resin into a product molding section to mold a molded product,
The mold unit includes the fixed mold, the movable mold, and the placing core,
The fixed side mold and/or the movable side mold in which the placed core is arranged include:
A recess opening facing the product molding section is provided, and a first air passage through which air can flow so as to communicate with the recess, and air can flow through a position different from the first air passage. a second air passage;
The placing core is formed to be movable within the recess, and is capable of closing the first air passage and the second air passage at the same time,
The second air passage is connected in this order to a detection means for detecting air pressure in the second air passage, and a negative pressure means for bringing the second air passage into a negative pressure state,
In the assembled state, the detection means is connected to a control means for controlling the operation of the injection molding machine,
When the molding of the molded product is completed and the movable mold is separated from the fixed mold, the placing core is located in the recess and the first air passage and the second air A mold unit characterized in that when the passage is closed and the detection means detects that a predetermined air pressure is present, a signal is output to the control means to enable the movable mold. 2. The mold unit according to claim 1, wherein an ejector capable of sending out the placed core toward the product molding section is disposed in the first air passage. Formed by a fixed side mold, a movable side mold that approaches and moves away from the fixed side mold, and a placing core arranged in the fixed side mold and/or the movable side mold. An injection molding machine that injects molten resin into a product molding section to form a molded product,
The fixed side mold and/or the movable side mold in which the placing core is placed are provided with a recess that opens to face the product molding section, and communicates with the recess. , a first air passage through which air can flow, and a second air passage through which air can flow are arranged at a position different from the first air passage,
The placing core is formed to be movable within the recess, and is capable of closing the first air passage and the second air passage at the same time,
The second air passage is connected in this order to a detection means for detecting air pressure in the second air passage, and a negative pressure means for bringing the second air passage into a negative pressure state,
comprising a control means that controls the operation of the injection molding machine and is connected to the detection means,
The control means may be arranged such that when the molding of the molded product is completed and the movable mold is separated from the fixed mold, the placing core is located in the recess and the first air passage is controlled. and an injection molding machine characterized in that, when the second air passage is closed and the detection means detects that a predetermined air pressure is present, the movable side mold is enabled to operate. 4. The injection molding machine according to claim 3, wherein the first air passage is provided with an ejector that can send out the placed core toward the product molding section. Claim 3, wherein the negative pressure means and the detection means are arranged outside the fixed side mold and/or the movable side mold in which the placed core is arranged. Or the injection molding machine according to 4. 5. The injection molding machine according to claim 3, wherein a filter is disposed between the second air passage and the detection means.

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