JP2003127187A - Valve gate mold assembly and molding method using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To smoothly release a molded product from a mold equipped with a valve device during opening a mold, in a valve gate mold assembly with a valve pin installed in a direction crossing the mold opening/closing direction. SOLUTION: The valve gate mold assembly is equipped with a liquid pressure cylinder device for driving the valve pin 61 in an axial direction D, and the valve pin 61 is arranged in a finely movable manner in a piston 73 of the liquid pressure cylinder device. A gate 33 is closed in such a way that the tip of the valve pin 61 is protruded into a cavity 23 from the gate 33. After a molding material is cured in the cavity 23, the tip of the valve pin 61 is extracted from the cavity 23 in such a way that the gate 33 is closed. After this extracting procedure, a cavity side 21 and a movable part 22 are opened in a mold opening/closing direction A. When a molded product is released, the tip of the valve pin 61 does not become caught by the molded product.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve gate mold apparatus used for injection molding of thermoplastic resin and a molding method using the same.

[0002]

SUMMARY OF THE INVENTION In a hot runner mold apparatus for constantly heating a resin, which is a molding material in a material passage to a gate to a cavity, to keep a molten state, a gate is mechanically operated by a valve pin which is a valve body. A valve gate type mold device that opens and closes is known. The hot runner mold device is intended to increase the molding efficiency, and the gate is closed to prevent the resin from leaking from the gate when the mold is opened.

In the valve gate type mold device, the valve pin is moved in the opening and closing direction of the mold to open and close the gate in manufacturing the mold.

However, depending on the condition of the molded product (product), it may not be possible to use a valve pin that moves in the mold opening / closing direction. For example, depending on the product shape, it is not possible to provide a gate at a position corresponding to the valve pin in the mold opening and closing direction, or if a gate mark is left at that position, it is not preferable for the product, or the product is long in the mold opening and closing direction. There are cases where the device that opens and closes with a normal stroke cannot open and close the mold.

Here, when a die using a valve body that moves in a direction intersecting with the die opening / closing direction is examined, as shown in FIG. 5, the fixed die 1 and the movable die 2, which are the die bodies, are vertically moved in the figure. The cavities 3 are opened and closed to form cavities 3 between them when the mold is closed. The cavity 3 includes a central portion 102 for molding the center of the molded product 101 and a peripheral wall portion 10 provided around the central portion 102.
The fixed mold 1 is provided with the gate 4 having the number 3 and communicating with the peripheral wall 103. A valve device 5 for opening and closing the gate 4 is provided movably in a valve casing 6 with a valve pin 7 as a valve body. The valve pin 7 has an axial direction perpendicular to the mold opening / closing direction and moves in this axial direction. By doing so, the gate closing portion 8 which is a tip end portion is fitted into the gate 4 so as to be freely inserted and removed, and the gate 4 is closed. A material passage 9 communicating with the gate 4 is provided in the valve casing 6, and the material passage 9 is connected to the runner of the manifold. A heater 10 is provided around the outer circumference of the valve casing 6 to heat the molding material in the material passage 9 so as to keep the molding material in a molten state. Further, the base end side of the valve pin 7 is connected to a fluid pressure cylinder device 11 such as a hydraulic cylinder device, and is driven by this fluid pressure cylinder device 11.

At the time of molding, the fixed mold 1 and the movable mold 2
After closing the molds and forming the cavity 3 between the fixed mold 1 and the movable mold 2, the valve pin 7 is moved in the direction away from the cavity 3 to open the gate 4. Then, a molten thermoplastic resin, which is a thermoplastic molding material, is injected into the fixed mold 1 from the injection molding machine. This resin flows into the cavity 3 from the gate 4 through the runner of the manifold and the material passage 9 in the valve casing 6. After the cavity 3 is filled with the resin in this way, the valve pin 7 is moved to the movable die 2 after the pressure is maintained.
Moving toward and fitting the gate 4 to close the gate 4. Then, after the resin in the cavity 3 is cooled and solidified, the fixed mold 1 and the movable mold 2 are opened. At this time, the resin in the cavity 3, that is, the molded product 101, first separates from the fixed mold 1 or the movable mold 2 and remains on one side due to the difference in the mold release resistance between the fixed mold 1 side and the movable mold 2 side. ,Molding
101 is separated and taken out by the operation of the ejection plate.
After that, the mold is closed again and the above molding cycle is repeated. Throughout the entire molding cycle, the runner of the manifold and the resin in the material passage 9 of the valve casing 6 are always kept in a molten state by the heating of the heater 10.

In such a valve gate type mold apparatus,
Manufacturing and assembling are performed so that the tip of the valve pin 7 is accurately aligned with the gate position. However, as described above, heating is performed to keep the resin in the material passage 9 in a molten state at all times. Since the valve pin 7 undergoes thermal expansion due to the temperature condition of, it is difficult to accurately align the tip end surface 8A of the valve pin 7 with the cavity forming surface 13 on the gate 4 side.

For this reason, the barbi pin 7 has its tip surface 8
A tends to be in a state of protruding into the cavity 3 or retracting into the gate 4. Then, after the resin in the cavity 3 is cured, when the mold release is performed with the tip of the valve pin 7 protruding into the cavity 3, the tip of the valve pin 7 is caught by the molded product 101, while the tip of the valve pin 7 is When the mold is released from the forming surface 11 while it is retracted into the gate 4, the part of the molded product 101 that has entered into the gate 4 and hardened is caught by the gate 4, and the molded product 101 can be smoothly released from the fixed mold 1. There is a problem of disappearing.

Further, as shown in FIG. 5, in the movable mold 2, the cavity forming surface 12 forming the peripheral wall portion 103 is provided with a draft, but depending on the shape of the molded product 101, as shown in FIG. When the cavity forming surface 13 forming the peripheral wall portion 103 of the fixed mold 1 is formed parallel to the mold opening / closing direction, the tip of the valve pin 7 is the cavity 3 as described above.
When it is retracted inside or inside the gate 4, the mold release process is not smoothly performed, and if the mold release is forcibly performed, the gate 4 of the molded product 101
There is also a problem that undercuts occur in the places.

The present invention is intended to solve such a problem, and in a valve gate type mold apparatus in which a valve body moves in a direction intersecting with a mold opening / closing direction to open / close a gate, a valve is opened when the mold is opened. An object is to smoothly release a molded product from a mold body provided with a device.

[0011]

In order to achieve the above object, the invention of claim 1 is a valve gate type mold device in which the axial direction of the valve body intersects the opening and closing directions of both mold bodies. The driving means includes a moving body that moves in the axial direction of the valve body, and the moving body is provided so that the valve body can be finely moved in the axial direction. It is provided with a fine movement drive means for moving.

At the time of molding, a plurality of mold bodies are closed to form a cavity between these mold bodies and a gate is opened,
The molding material is filled into the cavity from the material passage through the gate. Then, the gate is closed by the valve body of the valve device, and after the molding material in the cavity is solidified, the mold is opened to take out the molding material in the cavity, that is, the molded product. Then, the mold is closed again and the above molding cycle is repeated.

The valve body moves in a direction intersecting the opening / closing direction of the mold body to open / close the gate. When closing the gate
The fine movement drive means moves the valve body to the gate side with respect to the moving body, and the drive means sets the tip of the valve body to slightly project from the gate into the cavity. After the molding material in the cavity is solidified, the fine motion drive means retracts the tip of the valve body into the cavity with the gate closed. After that, by opening the two mold bodies, the molded product can be smoothly released from the mold body provided with the valve device without catching the tip of the valve body on the molded product.

According to a second aspect of the present invention, in the valve gate mold apparatus according to the first aspect of the present invention, the driving means is a fluid pressure cylinder device, and the moving body is a piston of the fluid pressure cylinder device. .

In this case, the piston, which is the moving body, moves a predetermined stroke by the fluid pressure, the valve body opens and closes the gate, and the finely moving drive means moves the valve body that is finely movable with respect to the piston. The tip of the valve body can be set in and out of the gate without moving the piston.

According to a third aspect of the present invention, in the valve gate mold apparatus according to the first or second aspect of the invention, the valve body is movably inserted into the movable body, and the movable body,
One-sided moving engagement portion that engages with the valve body to move the valve body to one side when moving in one side direction, and engages the valve body to moves the valve body to the other side when moving to the other side The other side moving engaging portion, the valve body is capable of fine movement between the engaging positions of the one side and the other side engaging portion, and the fine movement driving means is connected to the valve body. is there.

Thus, the valve body can be incorporated in the moving body so that the valve body can be finely moved, the valve body can be moved by the movement of the moving body, and the fine movement can be made to the base end side of the valve body. By connecting the drive means, the fine movement drive means can be compactly incorporated.

According to a fourth aspect of the present invention, there is provided a molding method using a valve gate type mold device, wherein a molding material is placed in the cavity in a molding method in which a valve body moves in a direction intersecting with an opening / closing direction of the mold body. After filling, close the gate with the tip of the valve body protruding from the gate into the cavity, and after the molding material in the cavity hardens, place the tip of the valve body in the cavity with the gate closed. It is a molding method in which both mold bodies are opened after the drawing.

After the filled molding material is hardened and before the mold is opened, the valve body is pulled out from the cavity, so that the valve body is not caught on the molded product at the time of mold release, and smooth mold release can be performed. .

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the valve gate mold apparatus of the present invention and a molding method using the same will be described below.
This will be described with reference to FIGS. The molded product 101 to be molded is the same as that described in FIG. 5 described above. First, the configuration of the valve gate mold apparatus will be described.

Reference numeral 21 is a fixed die, and 22 is a movable die. The fixed die 21 and the movable die 22, which are die bodies, move in the vertical direction in the figure (die opening / closing direction A) to open and close, and when the die is closed, they are separated from each other. A plurality of product cavities 23 in the shape of the product 101 are formed. The cavity 23 makes the axial direction of the product 101 coincide with the mold opening / closing direction A.

The fixed mold 21 includes a first fixed mold plate 26,
The first fixed-side mold plate 26 is provided with a second fixed-side mold plate 27 fixed to the surface opposite to the movable mold 22. These fixed mold plates 26 are used for the product 101 in the product cavity 23.
To form a surface corresponding to the outer surface of. Also, the first
A valve device built-in block 28 is fixed to the side of the second fixed mold plates 26 and 27. Although not shown, the main manifold is fixed to the surface of the second fixed-side mold plate 27 opposite to the movable mold 22, and the main manifold is fixed to the surface opposite to the movable mold 22 of this main manifold. Has a fixed-side mounting plate fixed to a fixed-side platen of the injection molding machine.

The first fixed mold plate 26 and the valve device incorporating block 28 are provided with a valve device incorporating hole.
31 and 32 are formed. The valve device incorporating hole 31 of the first fixed-side mold plate 26 has a substantially rotating body shape whose axial direction D is a direction orthogonal to the mold opening / closing direction A, and extends to the side surface of the first fixed-side mold plate 26. It is open. Further, the end of the valve device incorporating hole 31 on the opposite side to the opening is a hole-shaped gate 33 that opens into the product cavity 23.
The gate 33 is opened at the position of the cavity forming surface 24 of the first fixed mold plate 26 with the direction orthogonal to the mold opening / closing direction A as the axial direction D. It is a position that does not hinder the occurrence of. The cavity forming surface 24 is formed parallel to the mold opening / closing direction A and forms the outer surface of the peripheral wall portion 103.

A valve device 36 for opening and closing the gate 33 is incorporated in the valve device incorporating block 31 through the valve device incorporating hole 31 of the first stationary mold plate 26.

Next, the structure of the valve device 36 will be described. 37 is a valve casing, and this valve casing 37 has a substantially cylindrical shape whose axial direction D is a direction orthogonal to the mold opening / closing direction A.
It is built into 1,32. On one end side of the valve casing 37, a flange portion 38 having a substantially quadrangular prism shape is formed, and the flange portion 38 is formed in the valve device incorporating hole 32 of the valve device incorporating block 28 having substantially the same shape from above in the drawing. It is fitted. This valve device built-in hole
Although the valve casing 37 is prevented from rotating by the fact that the 32 and the flange portion 38 are substantially square pole-shaped,
The flat surface of the flange portion 38 (the upper surface in the drawing) is in contact with the surface of the runner 39, which is the material passage, at the outlet portion 39A. This liner 39 includes the manifold and the flange portion.
A heater 42 is provided which is formed in the sub-manifold 41 provided between the heaters 38 and heats the runner 39.

When assembling the valve device 36 into the fixed die 21, the valve casing 37 is assembled in the valve device incorporating block 28, and then the valve device incorporating block 28 is fixed to the first stationary mold plate 26. The valve casing 37 may be inserted into the valve device incorporating hole 31 of the first fixed mold plate 26. In addition, the flange part
A block 43 coaxially butted against 38 is fitted in the valve device incorporating hole 32.

A material passage 51 is formed in the valve casing 37 to connect the runner 39 of the sub-manifold 41 to the cavity 23 via the gate 33. Most of the material passage 51 extends in the axial direction D of the valve casing 37 and coaxially faces the gate 33.
One end of 51 is a bent portion 52, and the flange portion 38
Has an opening on the upper surface in the figure. The bent portion 52 communicates with the outlet 39A of the runner 39. A heater 53 that heats the material passage 51 is provided on the outer peripheral surface of the valve casing 37, and a cylindrical heater cover 54 that covers the heater 53 from the outer peripheral side is provided. Further, the valve casing 37 is provided with a temperature sensor 55 along the inside of the heater 53. The tip of the valve casing 37 on the gate 33 side is supported by being partially fitted to a fitting surface 56 formed in the valve device incorporating hole 31. In the other portions, a gap is formed between the valve casing 37 or the heater cover 54 and the first fixed mold plate 26 and the valve device incorporating block 28 for heat insulation.

Further, the material passage of the valve casing 37
A valve pin 61 is provided as a valve body that penetrates the inside of the shaft 51 coaxially and opens and closes the gate 33. The valve pin 61 has a direction orthogonal to the mold opening / closing direction A as an axial direction D and moves in the axial direction D.
It has a gate closing portion 62 at its tip end portion that is fitted in the gate 33 in a removable manner. Further, the valve pin 61 slidably penetrates the guide bush 63 fixed in the flange portion 38 of the valve casing 37, and the tip end on the gate 33 side is formed on the peripheral surface of the material passage 51. The support blades 64 are always slidably fitted inside. As a result, the valve pin 61 is supported by the valve casing 37.

The block 28 for incorporating the valve device is also provided.
Inside, a fluid pressure cylinder device 71, which is a driving means for driving the valve pin 61, is installed coaxially with the valve casing 37. In this example, the fluid pressure cylinder device 71 is a hydraulic cylinder device. The fluid pressure cylinder device 71 includes a cylinder chamber 72 and a piston 73, which is a movable body provided movably in the cylinder chamber 72.

The valve pin 61 is connected to the block 43.
Further, the piston 73 is provided so as to be capable of fine movement so as to penetrate a part of the valve device built-in block 28. The piston 73 has a through hole 74 formed in the axial direction D at the center, and the through hole 74 has a small diameter portion 74A on the gate 33 side.
The opposite side is a large diameter portion 74B, and a step surface 74C is formed between the small diameter portion 74A and the large diameter portion 74B. A washer 75 as an annular plate is fitted in the large-diameter portion 74B while being in contact with the step surface 74C, and this washer 75 serves as the other side engaging portion. A head portion 76, which is an engagement receiving portion, is provided on the base end side of the valve pin 61, the valve pin 61 penetrates the inside of the small diameter portion 74A and the washer 75, and the head portion 76 has the large diameter portion 74B.
It is located inside. Further, a cylindrical spacer ring 77 located on the outer peripheral side of the head portion 76 is coaxially fitted in the large diameter portion 74B. Further, a washer 78 as one side engaging portion is arranged on the side opposite to the gate 33 of the head 76 in the large-diameter portion 74B, and a pair of holesed screws 79, 80 are screwed into the large-diameter portion 74B. ing. These screws 79 and 80 are prevented from loosening by hitting each other, and both ends of the spacer ring 77 are abutted against the washer 75 abutting on the stepped surface 74C and the washer 78 abutting on the screw 79, so that they are sandwiched. There is. Further, the head portion 76 is formed slightly shorter than the spacer ring 77, so that the head portion 76 in the spacer ring 77 has an axial direction D.
Fine movement is possible. That is, fine movement drive means
By the drive of 81, the position where the head 76 contacts the washer 75 that is the other side engaging portion is the position closest to the gate 33, and the position where the head 76 contacts the washer 78 that is the one side engaging portion. Is the farthest position from gate 33.

Further, the actuating rod 82 of the fine movement drive device 81 is screwed into the head 76 through the screws 80 and 79 and the washer 78 from the base end side of the valve pin 61, and the fine movement drive is performed. The device 81 is a liquid pressure cylinder device such as a hydraulic cylinder, and moves the operating rod 82 forward and backward in the axial direction D.

On both sides of the cylinder chamber 72, small diameter portions 91, 92 having a diameter smaller than that of the cylinder chamber 72 are formed to communicate with each other.
Rod portion 73 slidably inserted into these small diameter portions 91, 92
A and 73B are provided on both sides of the piston 73, and the anti-gate
The rod portion 73B on the 33 side penetrates the small diameter portion 92 to expose the base end, and the large diameter portion 74B of the through hole 74 is formed in the rod portion 73B.
The base end of is open. Further, the small diameter portions 91 and 92 are provided with O-rings 95 and 96 for sealing which are in contact with the outer peripheral surfaces of the rod portions 73A and 73B, respectively. Further, an O-ring 97 for sealing that is in contact with the inner peripheral surface of the cylinder chamber 72 is provided on the outer periphery of the piston 73. Therefore, the inside of the cylinder chamber 72 is airtightly partitioned between the O-rings 95 and 97 on the gate 33 side of the cylinder chamber 72 and between the O-rings 97 and 96 on the side opposite to the gate 33. Liquid inlets and outlets 98 and 99 are formed on the side opposite to the gate 33, respectively. Further, the small diameter portion 92 is formed on the base end wall member 110 forming the base end wall portion of the cylinder chamber 72, and the base end wall member 110 is attachable to and detachable from the attaching / detaching means 111 such as a bolt on the built-in block 28. And the O-ring 112 for sealing keeps the cylinder chamber 72 airtight.

In this example, as shown in FIGS. 3 and 4, the spacer ring 77 is formed longer than the head portion 76 by the length L, and the length L is, for example, about 0.2 mm. Further, as shown in FIG. 1, when the piston 73 of the hydraulic cylinder device 71 is moved to the position closest to the gate 33, the fine movement driving means 81 drives the tip of the gate fitting portion 72 to move from the gate 33. The valve pin 61 can be driven to a protruding position and a position to be recessed in the gate 33. In this example, in the driven state, the length Lout at which the tip of the gate fitting portion 72 projects from the gate 33 at the position where the valve pin 61 is moved to the gate 33 side by the fine movement driving means 81 is the above-mentioned length. It is set to about 1/2 (L / 2) of L, and at the position where the valve pin 61 is moved to the side opposite to the gate 33 by the fine movement drive means 81,
Length Lin with which the tip of the gate fitting portion 72 is retracted from the gate 33
Is set to be half (L / 2) of the length L. Further, the driving force of the liquid pressure cylinder 71 is set to be larger than the driving force of the fine movement driving device 81. In the above setting, the protruding length Lout of the valve pin 61 is
The length may be set from less than L to more than 0. Also, since the gate 33 is closed with the tip of the valve pin 61 pulled out from the cavity 23,
The length of fitting of the gate 33 with the gate closing portion 62 is equal to or longer than the length Lin, that is, the length Lin of the tip of the valve pin 61 retracted into the gate 33 is the fitting length of the gate 33 with the gate closing portion 62. Shorter than the total length.

At the time of assembly, the valve casing 37 may be assembled into the valve device incorporating block 28, and then the valve pin 61 may be inserted into the valve casing 37. Conversely, at the time of disassembly, the valve pin 61 may be removed from the valve casing 37. After that, the valve casing 37 may be removed from the valve device built-in block 28.

As described above, the valve device 71 is oriented laterally with respect to the mold opening / closing direction A by making the axial direction D of the valve pin 61 orthogonal to the mold opening / closing direction A.

Further, a fluid passage 121 is formed surrounding the cavity 23 in the stationary mold plate 26 for passing a fluid fluid such as water for cooling the cavity 23.

The movable mold 22 has the first fixed mold plate 26.
And a movable side mold plate 131 that abuts the valve device built-in block 28, and a movable side receiving plate (not shown) fixed to the surface of the movable side mold plate 131 opposite to the fixed mold 21, Although not shown, a movable side mounting plate fixed to a surface of the movable side receiving plate opposite to the fixed die 21 via a spacer block and mounted on a movable platen of the injection molding machine is provided. Further, the core 132 fixed by being sandwiched between the movable side mold plate 131 and the movable side receiving plate projects toward the fixed mold 21, and the first fixed side mold plate 26 has a recess into which the core 132 is fitted. 26A is formed. On the core 132, the molded product 101 molded is formed into a movable mold 52.
An ejecting member 133 that is ejected from and is released from the movable mold 52 is externally fitted, and the ejecting member 133 can be driven in a direction away from the movable mold plate 131, and the molded product 101 is ejected from the movable mold 52 and released. It is what makes me. In addition, the movable block 22 includes slide blocks 1 on both sides of the protruding member 133.
34,134 are provided, and these slide blocks 134,134
Is movable to a position where it engages with the protruding member 133 and a non-engagement position.

Next, an injection molding method using the valve gate mold apparatus will be described. At the time of molding, first, the fixed mold 21 and the movable mold 22 are closed, a product cavity 23 is formed between the fixed mold 21 and the movable mold 22, and then the fluid pressure cylinder device 71 is driven to retract the valve pin 61. Open the gate 73. And from injection molding machine to fixed mold
A molten thermoplastic resin, which is a thermoplastic molding material, is injected into 21. This resin is the runner of the sub manifold 41.
39, and the material passage inside the valve casing 37.
The gas flows from the gate 33 into the cavity 23 through the space between the support blades 64 to which the valve pin 61 and the valve pin 61 are fitted. After the cavity 23 has been filled with the resin in this way, after holding pressure,
As shown in FIGS. 1, 2 and 3, the valve pin 61 is moved forward by driving the fluid pressure cylinder device 71, and the gate closing portion 62 thereof is fitted into the gate 33 to close the gate 33. In this case, the movement of the piston 73 of the hydraulic cylinder device 71 causes the washer 78 to engage with the head portion 76 and the valve pin 61 to the gate 33.
Move to the side. Here, when the fine movement driving means 81 is further driven to move the valve pin 61 by the length L toward the gate 33, the tip of the valve pin 61 projects from the gate 33 into the cavity 23 by the length Lout. Then, the resin in the cavity 23 is positively cooled by the cooling fluid passing through the liquid passage 121, and after the resin in the cavity 23 is cooled and solidified, the fine movement drive device 81 is driven before the mold opening. This moves the valve pin 61 to the side opposite to the gate 33. In this case, the operating rod 82 of the fine movement drive device 81 retracts and stops at the position where the head portion 76 abuts the washer 78. This is because the driving force of the fine movement driving device 81 is set to be smaller than the driving force of the fluid pressure cylinder device 71, and the fluid pressure cylinder device 71 moves the valve pin with the gate pin in FIG.
The force that pushes 61 toward the gate 33 side is set to be larger than the force by which the fine motion drive device 81 pulls the valve pin 61 toward the side opposite to the gate 33.
Even when the gate 33 is open, the hydraulic cylinder device
Since the force by which 71 pulls the valve pin 61 toward the side opposite to the gate 33 is set to be larger than the force by which the fine motion drive device 81 pushes the valve pin 61 toward the gate 33 side, the piston 73 cannot move due to the drive of the fine motion drive device 81. Absent. Then, by driving the fine movement drive device 81. The tip of the valve pin 61 is immersed in the gate 33 by the length Lin, and then the fixed mold 21 and the movable mold 12 are opened. At this time, the resin in the cavity 23, that is, the molded product 101 is first separated from the fixed mold 21 due to the difference in the mold release resistance between the fixed mold 21 side and the movable mold 22 side, and the tip of the valve pin 61 is molded product 101. The mold can be opened smoothly without being caught in the. Next, the molded product 101 is the protruding member 1
It is separated from the movable mold 22 by the operation of 33 and is taken out. Then, the mold is closed again and the above molding cycle is repeated.

As described above, in this embodiment, in accordance with the first aspect, the fixed mold 21 and the movable mold 22 which are a plurality of mold bodies which are opened and closed to form the cavity 23 between them when the mold is closed, and the fixed mold. A valve pin 61, which is a valve body that opens and closes a gate 33 that is provided in 21 and connects the material passage 51 to the cavity 23, and a liquid pressure cylinder device 71 that is a driving means that opens and closes the gate 33 by moving the valve pin 61 in the axial direction. The axial direction D of the valve pin 61 is set to the opening / closing direction A of the fixed mold 21 and the movable mold 22.
A valve gate type mold device crossed with respect to
The drive means includes a piston 73 that is a moving body that moves in the axial direction D of the valve pin 61. The piston 73 is provided with the valve pin 61 so that the valve pin 61 can be finely moved in the axial direction D, and the valve pin 61 is finely moved with respect to the piston 73. Since the means 81 is provided,
At the time of molding, the fixed mold 21 and the movable mold 22 are closed to form a cavity 23 between the fixed mold 21 and the movable mold 22 and the gate 33 is opened, and the material passage 51 is molded into the cavity 23 through the gate 33. After filling the material, the gate 33 is closed by the valve pin 61 of the valve device 36, and after the molding material in the cavity 23 is solidified, the mold is opened to open the cavity 23.
The molding material inside, that is, the molded product 101 molded is taken out. Then, the mold is closed again and the above molding cycle is repeated. In such molding, the valve pin 61 is
In order to open and close 33, the fixed die 21 and the movable die 22 are moved in the opening / closing direction A and the intersecting direction D. Then, when the gate 33 is closed, the fine movement driving means 81 moves the valve pin 61 to the gate 73 side with respect to the piston 73, and the tip of the valve pin 61 is slightly moved from the gate 33 into the cavity 23 by the liquid pressure cylinder device 71. Set to project. cavity
After the molding material in 23 is solidified, by the fine movement drive means 81,
With the gate 33 closed, the tip of the valve pin 61 is retracted outside the cavity 23, that is, outside the cavity forming surface 24. After that, by opening the fixed mold 21 and the movable mold 22, the tip of the valve pin 61 is not caught by the molded product 101, and the molded product 10 from the fixed mold 21 provided with the valve device 36.
1 can be released smoothly.

Further, as described above, in this embodiment, the driving means corresponds to the fluid pressure cylinder device 71.
Since the moving body is the piston 73 of the fluid pressure cylinder device 71, the piston 73 moves a predetermined stroke by the fluid pressure, the valve pin 61 opens and closes the gate 33, and the fine movement is possible with respect to the piston 73. Provided valve pin
By moving 61 by the fine movement driving means 81, it is possible to set the tip of the valve pin 61 to be projected and retracted from the gate 33 without moving the piston 73.

As described above, in this embodiment, according to claim 3, the valve pin 61 is movably inserted into the piston 73 which is a moving body, and the piston 73 is engaged with the valve pin 61 when moving in one direction. Valve pin 61 to one side (gate 33
A washer 78 that is a one-sided moving engaging portion that moves to the other side) and a other-side moving engaging portion that engages the valve pin 61 and moves the valve pin 61 to the other side (the side opposite the gate 33) when moving in the other side direction. Washer 75
The valve pin 61 is capable of fine movement between the engagement positions of the one side and the other side engagement portion, and the fine movement drive means 81 is provided on the base end side of the washer 78 which is one side engagement portion of the valve pin 61. Since the connection is made, the valve pin 61 can be incorporated in the piston 73 so that the valve pin 61 can be finely moved, and the valve pin 61 can be moved by the movement of the piston 73. Furthermore, from the washer 78 that is one side engaging portion of the valve pin 61. By connecting the fine movement drive means 81 to the base end side, the fine movement drive means 81 can be compactly incorporated.

As described above, in this embodiment, in accordance with the fourth aspect, the fixed mold 21 and the movable mold 22, which are a plurality of mold bodies that are opened and closed with each other, are closed to form a cavity between the fixed mold 21 and the movable mold 22. 23 is formed and the molding material is filled from the material passage 51 provided in the fixed mold 21 and the movable mold 22 through the gate 33, and when the molding material is filled in the cavity 23, the gate 33 is unexpectedly closed by the valve pin 61. In the molding method in which the valve pin 61 moves in the direction intersecting the opening / closing direction A of the fixed mold 21 and the movable mold 22, after filling the cavity 23 with the molding material,
With the tip of the valve pin 61 protruding from the gate 33 into the cavity 23, the gate 33 is closed, and after the molding material in the cavity 23 has hardened, the tip of the valve pin 61 is pulled out from the cavity 23 with the gate 33 closed. This is a molding method in which the fixed mold 21 and the movable mold 22 are opened after this withdrawal, and since the valve pin 61 is withdrawn from the cavity 23 before the mold is opened after the filled molding material has hardened, the valve pin 61 at the time of releasing the mold. Does not get caught on the molded product 101, and smooth mold release can be performed.

The present invention is not limited to the above embodiment, but various modifications can be made. For example,
The mold opening / closing direction and the axial direction of the valve body do not have to be completely orthogonal, and the axial direction of the valve body may be inclined with respect to the direction orthogonal to the mold opening / closing direction.

[0044]

According to the invention of claim 1, there is provided a valve gate type mold device in which the axial direction of the valve body is intersected with the opening and closing directions of the two mold bodies, wherein the driving means comprises: A moving body that moves in the axial direction of the valve body is provided, the valve body is provided on the moving body such that the valve body can be finely moved in the axial direction, and a fine movement drive unit that moves the valve body with respect to the moving body is provided. In the valve gate type mold device in which the valve body moves in the direction crossing the mold opening / closing direction to open / close the gate, the molded product can be smoothly released from the mold body provided with the valve device when the mold is opened.

According to a second aspect of the present invention, in the valve gate mold apparatus according to the first aspect of the present invention, the drive means is a fluid pressure cylinder device, and the moving body is a piston of the fluid pressure cylinder device. By moving the valve body, which is finely movable with respect to the piston, by the fine movement drive means, the tip of the valve body can be set in and out from the gate without moving the piston.

According to a third aspect of the invention, in the valve gate mold apparatus according to the first or second aspect of the invention, the valve body is movably inserted into the movable body, and the movable body is
One-sided moving engagement portion that engages with the valve body to move the valve body to one side when moving in one side direction, and engages the valve body to moves the valve body to the other side when moving to the other side The other side moving engaging portion, the valve body is capable of fine movement between the engaging positions of the one side and the other side engaging portion, and the fine movement driving means is connected to the valve body. Yes, the valve body can be incorporated into the moving body so that the valve body can be finely moved, and the valve body can be moved by the movement of the moving body. Further, the fine movement driving means is connected to the base end side of the valve body. By doing so, the fine movement driving means can be compactly incorporated.

A molding method using the valve gate mold apparatus according to a fourth aspect of the present invention is a molding method in which a valve body moves in a direction intersecting the opening / closing direction of the mold body, and a molding material is placed in the cavity. After filling, close the gate with the tip of the valve body protruding from the gate into the cavity, and after the molding material in the cavity hardens, place the tip of the valve body in the cavity with the gate closed. This is a molding method in which both molds are opened after this is withdrawn, and after the filled molding material has hardened, the valve body is pulled out from the cavity before opening the mold, so the valve body is molded when releasing. It is possible to perform a smooth mold release without being caught in the.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing an embodiment of a valve gate type mold device of the present invention.

2 is an enlarged cross-sectional view of the vicinity of the gate shown in FIG.

FIG. 3 is a sectional view of the gate and the moving body, showing a state in which the tip of the valve pin projects into the cavity.

FIG. 4 is a cross-sectional view of the gate and the moving body, showing a state in which the tip of the valve pin is pulled out from the inside of the cavity.

FIG. 5 is a sectional view showing an example of a conventional valve gate mold apparatus.

[Explanation of symbols]

21 Fixed type 22 Movable type 23 cavities 33 gates 36 valve device 37 Valve casing 39 Runner (material passage) 51 Material passage 61 valve pin 62 Gate fitting 71 Fluid pressure cylinder device (drive means) 72 cylinder chamber 73 piston 75 Washer (other side engaging part) 76 Head (engagement receiving part) 77 Spacer ring 78 Washer (One side engaging part) 81 Fine motion drive

Claims (4)

[Claims] 1. A plurality of mold bodies that open and close each other to form cavities between them when the mold is closed, a valve body that opens and closes a gate that is provided in the mold body, and that opens and closes a gate that communicates a material passage with the cavity, and the valve body. A valve gate type mold device, comprising: a driving unit that moves in the axial direction to open and close the gate, and intersects the axial direction of the valve body with the opening and closing directions of the mold units. Includes a moving body that moves in the axial direction of the valve body, the moving body is provided with the valve body such that the valve body can be finely moved in the axial direction, and a fine movement driving unit that moves the valve body with respect to the moving body is provided. A valve gate type mold device characterized in that 2. The valve gate mold apparatus according to claim 1, wherein the driving means is a fluid pressure cylinder apparatus, and the moving body is a piston of the fluid pressure cylinder apparatus. 3. A one-sided moving engagement in which the valve body is movably inserted into the movable body, and the movable body engages with the valve body and moves the valve body to one side when moving in one side direction. Part and an other side moving engagement part that engages with the valve body to move the valve body to the other side when moving to the other side, and between the engagement positions of the one side and the other side engagement part. 3. The valve gate mold apparatus according to claim 1, wherein the valve body is capable of fine movement, and the fine movement drive means is connected to the valve body. 4. A mold is formed by closing a plurality of molds which are opened and closed with each other to form a cavity between the molds, and a molding material is filled from a material passage provided in the mold through a gate to mold in the cavity. In the molding method in which the gate is unexpectedly closed by a valve body when filling the material, and the valve body moves in a direction intersecting with the opening / closing direction of the mold body,
After filling the cavity with the molding material, the gate is closed with the tip of the valve body protruding from the gate into the cavity, and after the molding material in the cavity is cured, the gate is closed with the molding material. A molding method using a valve gate type mold device, characterized in that the front end of the valve body is pulled out from the cavity, and after the pulling out, both die bodies are opened.