JP2002192561A - Mold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mold capable of adjusting cavity balance. SOLUTION: In a multi-cavity mold having a plurality of cavities 6, parts for changing the direction of a resin material filling route is provided to the individual runners 4 communicating with the gates 5 of the respective cavities and resin sump parts 3 are provided to the parts for changing the direction of a resin material filling route in a material straight advance direction and at least one of the resin sump parts 3 is constituted so as to be adjustable in its volume.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold for injection molding,
In particular, injection molding dies that can fine-tune the balance between cavities with multi-cavity dies, and multipoint gate dies that fill a cavity with materials from multiple gates. The present invention relates to an injection molding die capable of finely adjusting the balance.

[0002]

2. Description of the Related Art Injection molding is a processing method used for producing parts constituting products in all fields as a part processing method suitable for mass-producing parts having complicated shapes at low cost.

When a large number of molded articles of the same shape are produced by injection molding, a plurality of cavities of the same shape are provided in one mold to reduce the processing cost. “Multi-cavity” molding, in which a plurality of molded products are molded simultaneously by a mold, is performed.

[0004] One of the troubles in performing multi-cavity injection molding is the problem of balance between cavities. This is because when a sprue (usually one place) to which a nozzle of an injection molding machine is connected is branched at a runner portion to fill each cavity with resin, even if the sprue or the runner is designed to be symmetrical, the mold is not used. Due to processing errors, assembly errors, temperature distribution of the mold, and the like, the balance of resin filling and holding pressure among a plurality of cavities is lost, and the dimensional accuracy and appearance quality of molded products differ depending on the cavities.
If the cavity balance is broken, the injection speed, injection pressure, mold temperature,
If molding conditions such as resin temperature are adjusted, another cavity becomes defective, and a good product cannot be obtained from all cavities at the same time.

[0005] In order to improve such troubles,
It is necessary to adjust the mold to adjust the cavity balance to an optimum state.

The cavity balance can be adjusted by changing the cross-sectional shape and land length of the gate of each cavity, or by branching the resin flow path from the sprue portion where the molding machine nozzle is connected to each gate, and then adjusting the gate. By changing the shape of the runner up to each cavity, it is performed by adjusting the flow resistance of the resin up to each cavity and the balance between the solidification speed and the pressure loss.

[0007] In a mold in which cavity balance adjustment is required from the beginning of the mold design, for example, Japanese Patent Application Laid-Open No. 7-2
As disclosed in Japanese Patent No. 23242, when a part of a runner or a gate part is formed in a nested structure, and the nest is replaced to adjust the cross-sectional area of the flow path, thereby enabling the cavity balance to be adjusted. There are many.

Further, as disclosed in Japanese Patent Application Laid-Open No. 5-433, a slide core for changing the flow path cross-sectional area of the runner is provided, and the slide core is moved forward and backward to change the flow path cross-sectional area. The pressure transmission of the molten resin in the runner to the cavities may be changed to adjust the balance between the cavities.

The conventional technique relating to the balance adjustment between the cavities in the "multi-cavity mold" has been described above. Next, the conventional technique relating to the gate balance adjustment in the "multipoint gate mold" will be described.

When molding a molded article having a certain size and weight or a molded article having a complicated shape and poor filling properties by injection molding, it is difficult to completely fill the molded article with only one gate. In other words, a "multipoint gate" mold in which two or more gates are filled is used.

One of the troubles in performing injection molding using a multipoint gate mold is a problem of balance between gates. This is due to the shape of the runner and the temperature distribution of the mold when the resin is filled into the cavity from each sprue from the sprue (usually one place) to which the nozzle of the injection molding machine is connected. This is a phenomenon in which the balance between the filling of the resin and the holding pressure among a plurality of gates becomes inappropriate, and the dimensional accuracy of the molded product and the appearance quality such as weld are deteriorated. If the gate balance is lost, adjust the injection conditions such as injection speed, injection pressure, mold temperature, resin temperature, etc. so that the accuracy and appearance of specific parts in the molded product are good, Another part becomes defective, and it is impossible to obtain a good product in which the whole molded product satisfies all specifications at the same time.

In order to improve such troubles,
It is necessary to adjust the mold to adjust the gate balance to an optimum state.

The gate balance is adjusted by changing the cross-sectional shape and land length of each gate, or by branching the resin flow path from the sprue portion where the molding machine nozzle is connected to each gate, and then adjusting the individual gates. By changing the shape of the runner up to each cavity, the flow resistance of the resin up to each cavity, the solidification speed, and the balance of pressure loss are adjusted.

In a mold that requires fine adjustment of the gate balance from the beginning of the mold design, for example, Japanese Patent Application Laid-Open No.
As disclosed in Japanese Patent Application Laid-Open No. 141704, there is a case where a mold structure in which the flow resistance of the runner can be adjusted without disassembling the mold is provided so that the cavity balance can be adjusted while molding.

[0015]

However, the conventional method for adjusting the cavity balance in the multi-cavity mold described above has the following disadvantages.

A conventional method for adjusting the cavity balance in a multi-cavity mold is to adjust the balance between the resin filling and the holding pressure by changing the shape of the mold on the resin filling path from the molding machine nozzle to the cavity. Met. Therefore,
In addition to adjusting the cavity balance during fluid filling of the resin, this also has an effect on the holding pressure and the holding time applied to the cavity in the pressure holding step after filling.

For example, when a molded product having a thin rib 31 in a part of a relatively thick shape as shown in FIG. 6 is formed, the flow front of the resin flowing from the gate 32 reaches the root of the rib 31. Even when it reaches, the tip of the thin rib is not filled immediately, it is filled in the remaining thick shape with smaller flow resistance, and after the filling of the thick portion is completed, the resin pressure at the root of the thin rib rises The thin rib 31 is filled.

When such a molded product is molded in multiple pieces, in order to completely fill the thin ribs 31 in all the cavities, it is necessary to simultaneously fill all the cavities and apply pressure to the thin rib portions at the same time. . If the filling of a certain cavity is fast, even if the filling of the thick part in that cavity is completed, the pressure in the cavity does not immediately rise because the thick part of the other cavity is not filled, The flow end portion that has once stopped at the root of the thin rib of the cavity has a longer stopping time of the resin flow than other cavities. The pressure will rise only after the filling of the thick part of other cavities is completed, but when the pressure rises, the resin flow tip stopped at the rib base of the cavity where the filling is fast is cooled down and the viscosity increases. Due to the increase, the resin was not filled, and the thin rib portion sometimes caused a short circuit failure.

In this case, the short-circuit defect is eliminated by reducing the cross-sectional area of the gate of the cavity and delaying the resin filling so that the cavity is filled simultaneously with the other cavities (conventional cavity balance adjusting method).

However, since the cross-sectional area of the gate is reduced, the pressure loss in the gate portion is increased, and the gate sealing time is also shortened. Since the dwell time is also shortened, as a result, sinks occur in the thick part and the dimensions and warpage of the entire molded product are different from those of other cavities. Sometimes it became.

As described above, in a multi-cavity molded product, there is a problem of short-circuit failure of a thin portion affected by a delicate balance at the time of filling with a resin, and a delicate condition of a holding pressure and a holding time in a pressure holding step after filling. If there is a problem of inaccurate dimensions or warping that is affected by a poor balance, the conventional method of adjusting the cavity balance by adjusting the gate and runner shapes eliminates all problems at the same time, There was a problem that a good product could not be obtained.

On the other hand, the above-described conventional method of adjusting the cavity balance in the multipoint gate mold also has the following disadvantages.

In a conventional gate balance adjusting method for a multipoint gate mold, the shape of the mold on the resin filling path from the resin to the cavity of the molding machine is changed by changing the shape of the resin.
It was a method of adjusting the balance of the holding pressure. Therefore, the cavity balance at the time of fluid filling of the resin is adjusted, and at the same time, the holding pressure and the holding time applied to the cavity in the pressure holding step after the filling are affected.

For example, as shown in FIG. 10, a part having relatively thin wall portions 31A and 31B
When molding a molded product of a point gate, two gates 32A
Of the flow of the resin that has flowed in from the thin film 32 and the thin wall 31
Even if it reaches to, the entire thin-walled shape part is not immediately filled,
Filled to the remaining thicker shape with smaller flow resistance,
After the filling of the thick portion is completed, the thin portion 31 is filled only when the resin pressure increases.

Therefore, when such a molded product is molded by a two-point gate mold, it is necessary to simultaneously fill the two-point gate and simultaneously apply pressure to the thin part in order to completely fill the thin shape 31. . If the filling from the gate 32A is early, the thin-walled portion 31A on the side of the gate 32A stops once when the flow front slightly enters the thin-walled shape, and the filling from the other gate 32B proceeds to fill the thick-walled portion. Is completed for the first time, but when the pressure rises, the cooling of the flow front, which had already stopped at 31A, has progressed, and the viscosity of the resin has increased, and the thin wall on the gate 32A side, where the filling was quick, has been completed. In some cases, a short-circuit failure occurs in the shape portion 31A.

In this case, by reducing the cross-sectional area of the gate 32A and delaying the resin filling so that the gate 32A is filled at the same time as the other gate 32B, the short circuit defect is eliminated (conventional cavity balance adjusting method).

However, since the cross section of the gate is reduced, the pressure loss at the gate portion is increased, and the gate sealing time is also shortened. Since the pressure time is also shortened, as a result, the dimensions and warpage of the entire molded product are different between the two gates, and even if the filling failure is eliminated, the precision may be poor.

As described above, in the molded product of the multi-point gate, the problem of short-circuit failure of the thin portion affected by the delicate balance at the time of filling with the resin, and the balance between the holding pressure and the holding time in the pressure holding step after filling. If you have the problem of poor dimensions or warpage accuracy that affects the conventional method of adjusting the gate and runner shape to adjust the gate balance, you cannot solve all the problems at the same time and obtain a good product There was a problem.

The present invention solves the above-mentioned drawbacks of the conventional method of adjusting the cavity balance in the multi-cavity mold by adjusting only the balance of the filling step such as simultaneous filling of each cavity with the resin. Aiming to provide a mold that enables cavity balance adjustment without changing the balance of the subsequent pressure holding process, and to obtain a good product simultaneously for all cavities even in multi-cavity molding of molded products with strict precision standards as well as fillability. I have.

Further, according to the present invention, in order to solve the drawbacks of the above-mentioned conventional method in adjusting the gate balance of the multipoint gate mold, only the balance of the step of filling the resin from each gate is adjusted, and the maintenance after filling the resin is performed. Providing a mold that enables gate balance adjustment without changing the balance of the pressure process, and aims to obtain a good product even if it is a molded product of a multi-point gate where both the gate balance for filling and the required accuracy are strict. .

[0031]

Means for Solving the Problems The above-mentioned problems are solved,
In order to achieve the object, a molding die according to the present invention is:
A multi-cavity molding die having a plurality of cavities, wherein each runner communicating with a gate of each cavity has a portion for changing a direction of a filling path of a resin material, and changing a direction of the filling path. A resin pool portion is provided in a portion to be made in the material straight traveling direction, at least one of the resin pool portions,
The volume is adjustable.

Further, in the molding die according to the present invention, the resin reservoir is formed in a detachable nest, and the volume of the resin reservoir is adjusted by exchanging the nest.

In the molding die according to the present invention, the shape of the side surface of the resin reservoir is formed in the resin reservoir, and the resin reservoir can move in and out of the parting surface of the molding die. It is characterized in that a movable core is provided, and by adjusting the fixed position of the movable core, the external dimensions of the resin reservoir are changed to adjust the volume of the resin reservoir.

Also, in the molding die according to the present invention, a movable core is provided in the resin reservoir in the opening and closing direction of the molding die, and a fixed position of the movable core is adjusted. The volume of the resin reservoir is adjusted.

A molding die according to the present invention is a molding die of a multi-point gate type in which a resin material is filled in one cavity from a plurality of gates, and the molding die communicates with each of the plurality of gates. At least one of the runners
It has a portion that changes the direction of the filling path of the resin material, and a resin pool portion is provided in the material moving direction in the portion that changes the direction of the filling route, and the volume of the resin pool portion is adjustable. I have.

Further, in the molding die according to the present invention, the resin reservoir is formed in a detachable nest, and the volume of the resin reservoir is adjusted by replacing the nest.

Further, in the molding die according to the present invention, the resin reservoir has a shape of a side surface of the resin reservoir, and is capable of moving in and out of a parting surface of the molding die. It is characterized in that a movable core is provided, and by adjusting the fixed position of the movable core, the external dimensions of the resin reservoir are changed to adjust the volume of the resin reservoir.

Further, in the molding die according to the present invention, a movable core is provided in the resin reservoir in the opening and closing direction of the molding die, and a fixed position of the movable core is adjusted. The volume of the resin reservoir is adjusted.

[0039]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below.

According to one embodiment of the present invention, in a multi-cavity mold having a plurality of cavities, a runner communicating with a gate of each cavity has a portion where the direction of a material filling path changes. A molding die, characterized in that a resin pool is provided in a straight traveling direction, and at least one of the resin pools is capable of adjusting a volume of a resin pool portion.

Still another embodiment of the present invention is a multipoint gate type mold for filling a cavity from a plurality of gates with a material, wherein at least one of a plurality of runners respectively communicating with the plurality of gates is provided. On the one hand, there is a portion for changing the direction of a material filling path, and in a mold provided with a resin reservoir in this position in a direction in which the material travels, the volume of the resin reservoir can be adjusted. It is a mold.

Generally, in injection molding dies, a runner is often provided with a resin reservoir for the purpose of not filling the cavity with impurities such as cold slugs or of releasing gas generated from the resin at the time of filling. . In the present embodiment, the resin reservoir is provided in a portion in which the direction of the material filling path of the runner changes, in the material straight traveling direction. After the molten resin that has flowed through the runner goes straight and fills the resin pool, it flows into the runner that connects to the cavity.
If the volume of the resin pool is large, the filling of the cavity is delayed, and if the volume of the resin pool is small, the filling of the cavity is quick. Further, the holding pressure and the holding time in the holding pressure step after filling do not depend on the volume of the resin pool.

Therefore, in the multi-cavity mold, the volumes of the resin reservoirs are individually adjusted one by one on a mold in which one resin reservoir corresponds to only one cavity. Only the balance of the filling process such as simultaneous filling of the resin into each cavity is adjusted, and the cavity balance can be adjusted without changing the balance of the pressure holding process after filling the resin.

In a multi-point gate mold, the volume of the resin pool is individually adjusted on a mold in which one resin pool corresponds to only one gate. Only the balance of the filling process, such as the timing of filling the resin from each gate into the cavity, can be adjusted, and the gate balance can be adjusted without changing the balance of the pressure-holding process after filling the resin.

The specific mold structure will be described in detail below.

(First Embodiment) FIG. 1 shows a first embodiment of the present invention.
It is a figure showing a metallic mold of an embodiment. This is a four-cavity mold that branches into two runners 2 immediately below the sprue 1 and further branches into two branches. The resin filled from the sprue 1 passes through the runner 2, fills the resin pool 3, passes through the last runner 4 just before the gate, passes through the gate 5 and fills the cavity 6. The resin reservoir 3 is formed by a nest 7 that can be removed from the parting surface. The nest 7 can be replaced from the parting surface with the mold attached to the molding machine.

If it is desired to fill the resin into a specific cavity earlier than other cavities, the nest 7 forming the resin pool of the runner connected to that cavity is replaced with a nest having a shorter resin pool shape length. If you want to delay resin filling from other cavities, nest 7
May be replaced with a nest having a long resin reservoir shape length.
If nests with different lengths of resin reservoir shape are prepared in advance, each resin reservoir is formed while checking the filling condition of resin in each cavity while actually molding with the mold attached to the molding machine By properly selecting the nest 7 to be filled, the cavity filling balance can be made appropriate.

(Second Embodiment) FIG. 2 shows a second embodiment of the present invention.
It is a figure showing a metallic mold of an embodiment. This is a four-cavity mold that branches into two runners 2 immediately below the sprue 1 and further branches into two branches. The resin filled from the sprue 1 passes through the runner 2, fills the resin pool 3, passes through the last runner 4 just before the gate, passes through the gate 5 and fills the cavity 6. The shape of the side surface of the resin reservoir 3 is constituted by a movable core 17 that can advance and retreat in the in-plane direction of the parting surface.

FIG. 3 is a diagram for explaining a method of adjusting the movable core 17 of FIG. Inclined piece 18 is height adjustment piece 19
And is fixed to the side wall 20 of the template pocket by a bolt (not shown). By replacing the height adjustment piece 19, the height of the inclined piece 18 changes, the movable core 17 moves in the direction of the arrow in the figure, and the width dimension of the resin pool 3 changes, so that the resin pool 3 The volume is adjustable. By adjusting the height adjustment piece 19 to an appropriate height while confirming the filling state of the resin in each cavity while actually molding with the mold attached to the molding machine, the filling balance of the cavity is improved. It can be appropriate.

In this embodiment, the position of the movable core 17 is
The form in which the height is adjusted by adjusting the height of the height adjusting piece 19 has been described. Of course, a driving means for moving the movable core forward and backward may be provided in the mold as shown in JP-A-5-433. It is valid.

(Third Embodiment) FIG. 4 shows a third embodiment of the present invention.
It is a figure showing a metallic mold of an embodiment. This is an eight-cavity mold that branches into two runners 2 immediately below the sprue 1, and further reaches the cavity 6 through two forked branches. The resin filled from the sprue 1 passes through the runner 2, fills the resin reservoir 3 immediately before the gate, passes through the final runner 4 just before the gate, passes through the gate 5, and fills the cavity 6. A movable core pin 27 that can move forward and backward in the mold opening and closing direction protrudes from the resin reservoir 3.

FIG. 5 is a view for explaining details of the movable core portion of FIG. The movable core pin 27 can move forward and backward in the direction of the arrow in the figure, and the movable core pin 27 not shown
Can be fixed at an arbitrary position by the screw at the root of. When the movable core pin 27 is protruded, the volume of the resin pool decreases, and when the movable core pin 27 is retracted, the volume of the resin pool 3 increases, so that the eight movable core pins 27 provided in the resin pool near each cavity are fixed. By adjusting the position, the filling balance between the cavities can be made appropriate.

(Fourth Embodiment) FIG. 7 shows a fourth embodiment of the present invention.
It is a figure showing a metallic mold of an embodiment. It is a two-cavity mold that branches into two runners 2 immediately below the sprue 1 and then branches into two forks. The resin filled from the sprue 1 passes through the runner 2, fills the resin pool 3, passes through the last runner 4 just before the gate, passes through the gate 5 and fills the cavity 6. The resin reservoir 3 is formed by a nest 7 that can be removed from the parting surface. The nest 7 can be replaced from the parting surface with the mold attached to the molding machine.

If it is desired to fill the resin from a specific gate earlier than other gates, the nest 7 forming the resin pool of the runner connected to that gate is replaced with a nest having a shorter resin pool shape length. If it is desired to delay the resin filling from other gates, the nest 7 may be replaced with a nest having a longer resin reservoir shape length. If nests with different lengths of the resin pool shape are prepared in advance, it is possible to check the filling condition of the resin from each gate while actually molding with the mold attached to the molding machine, By selecting the proper nest 7, the gate filling balance can be made appropriate.

(Fifth Embodiment) FIG. 8 shows a fifth embodiment of the present invention.
It is a figure showing a metallic mold of an embodiment. The mold is a two-cavity two-gate gate mold that branches into two runners 2 immediately below the sprue 1 and then branches into two branches. The resin to be filled from the sprue 1 passes through the runner 2 and fills the resin pool 3, then passes through the final runner 4 just before the gate, and passes through the gate 5
Is filled into the cavity 6. The shape of the side surface of the resin reservoir 3 is constituted by a movable core 17 that can advance and retreat in the in-plane direction of the parting surface.

FIG. 3 is a diagram for explaining a method of adjusting the movable core 17 shown in FIG. An inclined piece 18 is fixed to a height adjusting piece 19 and a side face 20 of a template pocket by a bolt (not shown) in a state of being abutted. By replacing the height adjustment piece 19, the height of the inclined piece 18 changes, the movable core 17 moves in the direction of the arrow in the figure, and the width dimension of the resin pool 3 changes, so that the resin pool 3 The volume is adjustable. While actually molding with the mold attached to the molding machine, while checking the filling state of the resin in each cavity,
By adjusting the height adjustment piece 19 to an appropriate height, the filling balance of the cavity can be made appropriate.

In this embodiment, the position of the movable core 17 is
The form in which the height is adjusted by adjusting the height of the height adjusting piece 19 has been described. Of course, a driving means for moving the movable core forward and backward may be provided in the mold as shown in JP-A-5-433. It is valid.

(Sixth Embodiment) FIG. 9 shows a sixth embodiment of the present invention.
It is a figure showing a runner part of a metallic mold of an embodiment. This is a two-cavity three-plate mold with four cavity gates, each of which is branched into two runners 2 immediately below the sprue 1 and further divided into eight pinpoint gates through two forked branches.
The resin filled from the sprue 1 passes through the runner 2, fills the resin pool 3 immediately before flowing into the secondary sprue 14, and then fills the cavity 6 via the secondary sprue 14 and a gate (not shown). A movable core pin 27 that can move forward and backward in the mold opening and closing direction protrudes from the resin reservoir 3.

FIG. 5 is a view for explaining details of the movable core portion of FIG. The movable core pin 27 can move forward and backward in the direction of the arrow in the figure, and the movable core pin 27 not shown
Can be fixed at an arbitrary position by the screw at the root of. When the movable core pins 27 protrude, the volume of the resin reservoir 3 decreases, and when the movable core pins 27 are retracted, the volume of the resin reservoir 3 increases. By adjusting the fixing position, the filling balance between the gates can be made appropriate.

As in the embodiment described above, the runner is not limited to the two-plate mold of the side gate, but is extended to the part where the runner changes to the secondary sprue even with the three-plate mold of the pinpoint gate. If the resin reservoir is provided so that the volume of the resin reservoir can be individually adjusted, it is possible to perform the balance adjustment between the cavities of the multi-cavity mold and the gate balance adjustment of the multipoint gate mold.

Further, by using the present invention together with the conventional balance adjusting method for changing the shape of the runner and the gate on the resin filling path, the simultaneous filling property of the resin and the holding pressure and the holding time of the holding pressure step can be reduced. A more delicate balance adjustment that takes into account both factors is possible, and even for molded products with strict resin filling and precision standards and a very narrow range of molding conditions, good products in multi-cavity dies and multi-point gate dies Can be obtained.

[0062]

As described above, according to the present invention,
In the multi-cavity mold, it is possible to adjust the balance of the filling process such as simultaneous filling of the cavities with the resin and to adjust the cavity balance without changing the balance of the pressure-holding process after filling the resin.

Further, in the multipoint gate mold, only the balance of the filling timing of the resin from each gate is adjusted,
The gate balance can be adjusted without changing the balance of the pressure holding step after filling the resin.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a mold according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a mold according to a second embodiment of the present invention.

FIG. 3 is a view for explaining a method of adjusting the movable core of FIG. 2;

FIG. 4 is a diagram illustrating a mold according to a third embodiment of the present invention.

FIG. 5 is a diagram illustrating details of a movable core portion in FIG. 4;

FIG. 6 is a diagram illustrating a shape of a molded product.

FIG. 7 is a diagram illustrating a mold according to a fourth embodiment of the present invention.

FIG. 8 is a diagram illustrating a mold according to a fifth embodiment of the present invention.

FIG. 9 is a diagram illustrating a mold according to a sixth embodiment of the present invention.

FIG. 10 is a diagram illustrating the shape of a molded product.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sprue 2 Runner 3 Resin pool 4 Runner 5 Gate 6 Cavity 7 Nesting 17 Movable core 18 Inclined piece 19 Height adjustment piece 27 Movable core pin

Claims (8)

[Claims] 1. A multi-cavity molding mold having a plurality of cavities, wherein each runner communicating with a gate of each cavity has a portion for changing the direction of a resin material filling path, and A molding die, characterized in that a resin reservoir is provided in a portion in which the direction of the path is changed in a direction in which the material travels straight, and at least one of the resin reservoirs is configured so that its volume can be adjusted. 2. The molding die according to claim 1, wherein the resin pool is formed in a detachable nest, and the volume of the resin pool is adjusted by exchanging the nest. 3. A movable core having a shape of a side surface of the resin reservoir, a movable core capable of moving back and forth in an in-plane direction of a parting surface of the molding die, and fixing the movable core. The molding die according to claim 1, wherein a volume of the resin reservoir is adjusted by adjusting a position of the resin reservoir by changing an outer dimension of the resin reservoir. 4. A volume of the resin reservoir is adjusted by providing a movable core in the resin reservoir in the opening and closing direction of the molding die and adjusting a fixed position of the movable core. The molding die according to claim 1, characterized in that: 5. A molding die of a multi-point gate type wherein a resin material is filled into one cavity from a plurality of gates, wherein at least one of a plurality of runners each communicating with the plurality of gates includes a resin. It has a portion for changing the direction of the filling path of the material, and a resin pool portion is provided in the portion for changing the direction of the filling route in a direction in which the material goes straight, so that the volume of the resin pool portion can be adjusted. Mold for molding. 6. The molding die according to claim 5, wherein the resin reservoir is formed in a detachable nest, and the volume of the resin reservoir is adjusted by exchanging the nest. 7. A movable core having a shape of a side surface of the resin reservoir, a movable core capable of moving back and forth in an in-plane direction of a parting surface of the molding die, and fixing the movable core. 6. The molding die according to claim 5, wherein the volume of the resin reservoir is adjusted by adjusting the position to change the outer dimensions of the resin reservoir. 8. The volume of the resin reservoir is adjusted by providing a movable core in the resin reservoir in the opening and closing direction of the molding die and adjusting a fixed position of the movable core. The molding die according to claim 5, characterized in that: