CN110248793B

CN110248793B - Molding die

Info

Publication number: CN110248793B
Application number: CN201880008860.6A
Authority: CN
Inventors: 三浦慎吾; 井出彻; 森浦智也; 宫冈哲也; 江藤拓也
Original assignee: Honda Motor Co Ltd
Current assignee: Honda Motor Co Ltd
Priority date: 2017-01-27
Filing date: 2018-01-26
Publication date: 2021-06-11
Anticipated expiration: 2038-01-26
Also published as: CN110248793A; JPWO2018139566A1; WO2018139566A1; JP6741354B2

Abstract

The molding die (10) has a stationary die (14), a movable die (16), and a nest (18). The nest (18) is capable of forming a cavity (20) between it and the stationary mold (14) into which molding material flows. The nest (18) has a contact portion (58a) that contacts the movable mold (16) in the expanded state, and a non-contact portion (58b) that does not contact the movable mold (16) by forming a gap (60) between the non-contact portion and the movable mold (16). The nest (18) has a hollow portion (70), and the hollow portion (70) extends from an end surface (64a) on the opposite side of the side where the cavity (20) is formed to the vicinity of the cavity (20) and is not communicated with the cavity (20).

Description

Molding die

Technical Field

The present invention relates to a molding die (molding die) for producing a molded product by injection molding (injection molding) with a nest (liner) housed inside.

Background

In order to suppress molding defects of a molded product, it is necessary to appropriately control the temperature of the mold itself at the time of injection molding. Therefore, for example, a molding die disclosed in japanese patent application laid-open No. 4503351 is configured to have a plurality of cavities and passages communicating with the cavities on the back surfaces of the cavities of the fixed-side die and the movable-side die, and to flow a heat medium (high-temperature water or low-temperature water) through the plurality of cavities and passages. That is, the temperature of the molding die can be adjusted by flowing the heat medium.

In such injection molding, the insert may be housed and fixed in the molding die in advance, and the temperature may be locally (or entirely) adjusted by the insert. For example, the temperature can be adjusted by providing a flow path for flowing the heat medium in the nest.

Disclosure of Invention

However, when a relatively large molded product such as a cowl (cowl) of a vehicle (e.g., a motorcycle) is injection molded, the nest inevitably becomes large and has a complicated shape. Therefore, the length of the flow path of the heat medium provided in the jacket also increases. Therefore, even if the temperature is adjusted by nesting at the time of injection molding of the molded product, a large amount of energy (temperature rise energy, cooling energy) is required as a result, which causes an increase in manufacturing cost.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a molding die capable of quickly adjusting or maintaining the temperature of the nest with a simple structure, thereby saving energy during injection molding and reducing manufacturing cost.

In order to achieve the above object, a molding die according to the present invention includes a first die, a second die, and a nest, wherein the first die and the second die are clamped; the nest is disposed in the first mold, and is capable of forming a cavity into which a molding material flows between the nest and the second mold, and has an abutting portion that abuts against the first mold in an expanded state due to temperature rise, a non-abutting portion, and a hollow portion; the non-abutting portion forms a gap between it and the first mold without abutting in the expanded state; the hollow portion extends from an end surface on the opposite side of the cavity to the vicinity of the cavity, and is not communicated with the cavity.

According to the above configuration, the molding die can favorably position the first die and the nest by the abutting portion of the nest, and the cavity can be formed with high accuracy. In addition, in the expanded state, by forming a gap between the non-contact portion of the nest and the first mold, heat conduction between the nest and the first mold can be suppressed satisfactorily by the heat insulating effect of the gap. Furthermore, since the nest has a hollow portion, the hollow portion also has a heat insulating effect. Therefore, the nesting temperature can be maintained by a simple structure, and energy for adjusting the nesting temperature can be saved during injection molding. As a result, the manufacturing cost for manufacturing the molded article can be reduced.

Preferably, the nest has a plurality of hollow portions with a wall portion therebetween.

Since the molding die has a plurality of hollow portions, the heat insulating effect of the nest can be further improved while maintaining the shape of the nest.

Preferably, the first mold has a housing space for housing the nest, and the gap is formed on a back side of the housing space with respect to the abutting portion and is formed over an entire circumferential direction of an inner circumferential surface constituting the housing space.

Since the abutting portion is disposed in the vicinity of the opening of the housing space, the molding die can maintain the shape of the cavity with higher accuracy. Further, since the clearance is formed over the entire circumferential direction of the inner circumferential surface of the first die, the energy for adjusting the temperature of the nest can be significantly reduced.

Further, it is preferable that a heat insulating member is provided between the nest and the first mold.

The molding die can further suppress heat conduction to the first die by the heat insulating member.

Here, it is preferable that the nest has a flow channel through which a heat medium for adjusting the temperature of the nest itself flows, and the flow channel can discharge the heat medium as needed. .

The nest is able to quickly adjust the temperature of the nest itself through the flow channel. The flow channel can exhibit a heat insulating effect by discharging the heat medium, as in the hollow portion.

Preferably, the flow channel is provided in a molding wall portion constituting the cavity at least at a position closer to the second mold than the hollow portion.

The nested molding wall portions can be smoothly adjusted in temperature by the heat medium, thereby giving an appropriate temperature to the molding material injected into the cavity.

Preferably, the flow channel is formed to extend between the gap and the hollow portion and to communicate with a flow channel provided in the molding wall portion.

Since the flow channel extends between the gap and the hollow portion, a heat insulating effect is exerted around the flow channel, and a heat medium can be favorably made to flow while suppressing a temperature change.

Preferably, the heat medium includes a refrigerant, and the flow channel is configured to cool the nested cooling mechanism at the time of injection molding.

The molding die can easily cool the nest by a cooling mechanism for flowing a refrigerant in the flow passage, and can favorably promote solidification of the molding material.

The flow path is grouped for each of the parts of the nest, and the heat medium can be caused to flow for each of the parts.

The molding die can perform detailed temperature adjustment according to the position of the molded product by grouping the flow channels for each nested position.

Preferably, a driven nest is provided in the first mold, the driven nest partially closing the gap and being configured as another member different from the nest and being freely displaceable, the driven nest allowing thermal expansion and thermal contraction of the nest while continuously closing the gap.

Since the molding die has the driven nest, the molding material can be prevented from entering the gap satisfactorily while allowing thermal expansion of the nest.

According to the present invention, the molding die can rapidly adjust or maintain the temperature of the nest by a simple structure, thereby saving energy during injection molding and reducing manufacturing cost.

Drawings

Fig. 1 is an explanatory view schematically showing a molding die and an injection molding apparatus according to an embodiment of the present invention.

Fig. 2 is a perspective view showing the overall structure of the nest of fig. 1.

Fig. 3 is an enlarged explanatory view of the movable mold and the nest shown in fig. 1.

Detailed Description

Next, a molding die according to the present invention will be described in detail with reference to the accompanying drawings by referring to preferred embodiments.

A molding die 10 according to an embodiment of the present invention is a molding die for injection molding a cowl (molded article) of a vehicle, and is provided in an injection molding device 12 as shown in fig. 1. In the following description, the direction is indicated based on the direction of arrow X, Y, Z in fig. 1 as necessary. Specifically, the arrow X direction is the left-right direction in fig. 1, the arrow Y direction is the front-back direction of the paper in fig. 1, and the arrow Z direction is the up-down direction in fig. 1.

The molding die 10 has, as main components, a fixed die 14 (second die), a movable die 16 (first die), and a nest 18. The nest 18 has a temperature adjustment function of the nest 18 itself, and the nest 18 is attached to the movable mold 16 to form a cavity 20 between the movable mold 16 and the stationary mold 14 along with the movement of the movable mold 16. A molded product is molded by injecting a molding material into the cavity 20.

The cowl as a molded article is formed in a three-dimensional shape having a predetermined length in the front-rear direction (arrow Z direction) and the width direction (arrow Y direction) of the vehicle and a sufficient length in the height direction (arrow X direction). Therefore, the molding die 10 also has a sufficient length in the arrow X direction. Needless to say, the molded article produced by the molding die 10 is not limited to the cowl. The shape of the cavity 20 of the molding die may be appropriately designed according to the shape of the molded product.

The injection molding apparatus 12 includes a clamping mechanism 22 for clamping the molding die 10, and the clamping mechanism 22 supports the fixed mold 14 via a fixed platen 24 and supports the movable mold 16 via a movable platen 26. The stationary platen 24 is firmly fixed to a support body, not shown, provided in the injection molding apparatus 12, and the stationary platen 14 and the movable platen 16 are arranged to face each other.

The movable disk 26 is connected and fixed to a movable actuator 28. The movable actuator 28 is operated under the control of the control unit 30 of the injection molding apparatus 12, and reciprocates the movable platen 26 and the movable mold 16 in the arrow X direction. The movable mold 16 and the fixed mold 14 are moved relatively in the direction of the arrow X1, whereby the movable mold 16 and the fixed mold 14 are brought into proximity and contact (mold clamping). Conversely, when the movable mold 16 and the fixed mold 14 are moved relative to each other in the direction of the arrow X2, the mold clamping between the movable mold 16 and the fixed mold 14 is released, and the movable mold 16 moves away from the fixed mold 14.

The injection molding apparatus 12 further includes an injection mechanism 32 for injecting a molding material into the cavity 20. The injection mechanism 32 has an injection nozzle 34, and the injection nozzle 34 is inserted into the stationary platen 24 so as to communicate with a sprue (squirle) 40 of the stationary mold 14. The injection mechanism 32 is provided with a hopper (hopper), a heater, a screw, and the like (not shown). The injection mechanism 32 supplies the molding material from the hopper to the injection nozzle 34 under the control of the control unit 30, heats and melts the molding material by the heater, and moves the molding material by the rotational drive of the screw in the injection nozzle 34. Accordingly, the injection nozzle 34 injects the molding material from the tip. In addition, the injection mechanism 32 may take other configurations.

The fixed mold 14 of the molding die 10 constitutes one surface of the cavity 20 as described above. The stationary mold 14 includes a base portion 36 and a projection portion 38, wherein the base portion 36 is joined to the stationary platen 24; the protrusion 38 is continuous with the base portion 36 and protrudes from the base portion 36 toward the movable mold 16 (in the direction of the arrow X2).

The base portion 36 is formed in a block shape having a predetermined thickness, and the base portion 36 is expanded outward (in the arrow Y-Z direction) from the projection portion 38 when viewed from the front side of the driven die 16. The surface (the surface around the convex portion 38) of the base portion 36 facing the movable mold 16 forms a partition surface 36a serving as a boundary reference of the molding die 10.

A guide pin boss (36 b) is provided on the partition surface (36 a) of the base portion (36), and the guide pin boss (36 b) guides and positions the mold (10) for molding in cooperation with a guide pin (56) described later. Further, a sprue 40, a runner (runner)42, and a gate (gate)44 for supplying molten metal of the molding material are provided in the base portion 36 so as to communicate between the cavity 20 and the injection nozzle 34.

The convex portion 38 of the fixed mold 14 is a portion formed to protrude in accordance with the shape of the molded product, and faces the nest 18 housed in the movable mold 16. That is, a mold shape for forming the shape of one surface of the molded article is formed on the surface of the convex portion 38 (the portion protruding from the partition surface 36 a).

Although not shown, the fixed mold 14 has an Ejector mechanism (Ejector mechanism) for taking out an injection-molded article from the fixed mold 14. Furthermore, the ejection mechanism may also be provided on the movable mold 16 or the nest 18.

On the other hand, the movable die 16 of the molding die 10 is formed in a concave shape having a housing space 16a of the housing nest 18. Specifically, the movable mold 16 includes a bottom wall 46 fixed to the movable platen 26 and side walls 48 projecting in the direction of arrow X1 from 4 sides of the bottom wall 46, and the movable mold 16 is box-shaped as a whole. The movable mold 16 is provided with a driven nest 50, and the driven nest 50 is configured as another member different from the nest 18 and operates based on expansion of the nest 18.

A fixing member 52 such as a bolt for fixing the boss 18 is provided on the bottom wall 46 of the movable mold 16. Further, a heat insulating plate 54 (heat insulating member) is provided on a surface of the bottom wall 46 facing the housing space 16 a. On the other hand, the side wall 48 surrounds the housing space 16a, and an end surface of a projecting end (an end portion on the opposite side from the bottom wall 46) thereof constitutes a partition surface 48a facing the partition surface 36a of the fixed mold 14. The side wall 48 is provided with a plurality of guide pins 56 projecting from the partition surface 48a in the direction of arrow X1.

The fixing member 52 penetrates the bottom wall 46 of the movable mold 16 and the heat insulating plate 54, and connects and holds the nest 18. Here, the fixing member 52 functions as a base point when the nest 18 expands, in the mold 10 for molding, in consideration of the degree of expansion of the nest 18 caused by heating at the time of injection molding.

The heat insulating plate 54 is disposed and fixed between the movable mold 16 (the bottom wall 46) and the nest 18, thereby suppressing heat conduction between the bottom wall 46 and the nest 18. The heat shield plate 54 is formed flat, and holes for passing the fixing member 52 and the

flow passages

68 and 74 described later are provided at appropriate positions on the plate surface. The material of the heat insulating plate 54 is not particularly limited, and may be, for example, ceramic (porous body) having bubbles, a material having low thermal conductivity, or the like.

The guide pin 56 projects short from the partition surface 48a of the movable mold 16, and is inserted into the guide pin boss 36b on the fixed mold 14 side when the fixed mold 14 and the movable mold 16 are closed. Accordingly, the fixed mold 14 and the movable mold 16 are prevented from being displaced in the arrow Y-Z direction, and a molded article is molded with high accuracy.

The nest 18 of the molding die 10 is inserted into and fixed to the housing space 16a, and is disposed and fixed at a position facing the projection 38 of the fixed die 14. The nest 18 has a sufficient thickness from the bottom wall 46 toward the fixed mold 14 so as to mold a molded article having a predetermined height as described above.

The thickness of the nest 18 corresponds to the protruding length of the movable mold 16 (the side wall 48), and the peripheral portion 58 near the side wall 48 protrudes from the bottom wall 46 until it coincides with the partition surface 48 a. On the other hand, the portion inside the peripheral portion 58 is recessed from the partition surface 62a toward the bottom wall 46 side in accordance with the shape of the convex portion 38 of the fixed mold 14.

The peripheral portion 58 of the nest 18 has an abutting portion 58a in the vicinity of the opening portion of the movable mold 16 (the arrow X1 direction side), and the abutting portion 58a is in close contact with (abuts against) the inner peripheral surface of the side wall 48 in a state where the temperature of the nest 18 is increased and the side wall is expanded. The peripheral portion 58 of the nest 18 has a non-contact portion 58b on the back side of the housing space 16a relative to the contact portion 58a, and the non-contact portion 58b does not contact the inner peripheral surface of the side wall 48 even in a state where the temperature of the nest 18 is increased and the nest is expanded. That is, a portion of the nest 18 forms a gap 60 with respect to the movable mold 16.

In more detail, the nest 18 is functionally divided along its thickness direction (arrow X direction) into a formed wall portion 62 and a material removal portion 64.

The molding wall portion 62 is a portion that directly faces the stationary mold 14 at a position away from the bottom wall 46. The molded wall portion 62 has a sufficient thickness to maintain the cavity 20 during injection molding, and continues in the direction of the arrow Y-Z perpendicular to the thickness direction while maintaining the thickness. The outer portion of the molded wall 62 in the arrow Y-Z direction constitutes an abutment portion 58a, and is fixed in contact with the inner peripheral surface of the side wall 48. The molding wall portion 62 has a partition surface 62a near the abutting portion 58a by a surface facing the fixed mold 14. The molding wall portion 62 is recessed inward in the arrow X2 direction from the partition surface 62a to form a recessed space 63 into which the convex portion 38 of the fixed mold 14 enters.

When the movable mold 16 and the fixed mold 14 are clamped, a part of the molding wall portion 62 contacts the fixed mold 14. In detail, the cavity 20 is formed inside the partition surface 62a by the partition surface 62a contacting the partition surface 36a of the base portion 36 of the fixed mold 14. That is, a surface of the molding wall 62 facing the fixed mold 14 at a position inside the partition surface 62a constitutes one surface of the cavity 20. In addition, the wall portion 62 to be molded according to the present embodiment can maintain the shape of the cavity 20 by the surface contact of the portions 62b to be abutted, which are set substantially at the center, with the convex portion 38 of the fixed mold 14 in addition to the partition surface 62 a.

Here, a plurality of flow channels 68 through which a heat medium flows are provided as the temperature adjusting mechanism 66 (including a cooling mechanism) inside the molded wall portion 62. The plurality of flow channels 68 communicate with a flow channel 74 provided in the material removing portion 64 described later, and supply and discharge the heat medium. Examples of the heat medium include water, oil, and the like, the temperature of which has been adjusted. The respective flow channels 68 are collected by the heat medium and brought into a vacuum state (or a state in which air whose flow is stopped is present).

The plurality of flow channels 68 extend in the direction of the arrows Y-Z within the forming wall 62, enabling the temperature of the forming wall 62 (particularly near the cavity 20) to be adjusted in a concentrated manner. In addition, the plurality of flow passages 68 are grouped for each portion of the molding wall 62, so that the heat medium is supplied and discharged for each portion. Accordingly, the molded wall 62 can be temperature-adjusted at a site (e.g., the portion to be abutted 62 b) to be particularly cooled or heated. The plurality of flow passages 68 may be provided separately as a high-temperature flow passage through which a high-temperature heat medium (heat medium) flows and a low-temperature flow passage through which a low-temperature heat medium (refrigerant) flows.

On the other hand, as shown in fig. 1 and 2, the material removal portion 64 of the nest 18 is provided between the molding wall portion 62 and the bottom wall 46, and has a plurality of hollow portions 70 in which the material of the nest 18 itself is cut out. That is, the material-removed portion 64 of the nest 18 corresponds to a portion having the hollow portion 70 in the arrow X direction, and on the contrary, the molded wall portion 62 corresponds to a portion having no hollow portion 70.

Further, the outer peripheral portion of the material removing portion 64 in the arrow Y-Z direction is cut away inward from the outer peripheral portion (abutting portion 58a) of the molded wall portion 62 in the arrow Y-Z direction. That is, the outer peripheral portion of the material removing portion 64 constitutes the non-contact portion 58b that does not contact the side wall 48 in the state where the movable mold 16 is housed. The notch (non-abutting portion 58b) of the material removing portion 64 is provided in the entire circumferential direction of the inner circumferential surface of the side wall 48. Of course, a portion of the material removal portion 64 may be in contact with the side wall 48.

The hollow portions 70 are provided in a substantially matrix shape with respect to the arrow Y-Z direction, and do not communicate with the cavity 20. In the present embodiment, there are 9 hollow portions 70 in total, 3 rows in the arrow Y direction and 3 columns in the arrow Z direction. The hollow portions 70 have different depths in the direction of the arrow X depending on the shape of the molded wall portion 62 from the end surface 64a located on the opposite side of the molded wall portion 62 (so as to ensure the thickness of the molded wall portion 62). More specifically, when the entire thickness of the nest 18 is large in the X direction according to the shape of the cavity 20, the hollow portion 70 is formed to be deep at the bottom and large in the arrow Y-Z direction. On the other hand, when the wall thickness of the entire nest 18 is small in the X direction, the hollow portion 70 is formed to be shallow at the bottom and small in the arrow Y-Z direction.

The block wall portion 72 of the material removal portion 64 partitioning the plurality of hollow portions 70 is designed in a shape that can sufficiently obtain the strength of the nest 18 in the arrow X direction even if the plurality of hollow portions 70 exist. The block wall portion 72 is formed to have a wide width in the arrow Y-Z direction at a shallow portion of the hollow portion 70 (near the center portion in the arrow Y-Z direction), and to have a narrow width in the arrow Y-Z direction at a deep portion of the hollow portion 70 (near the outer peripheral portion in the arrow Y-Z direction).

The block wall portion 72 is provided with a plurality of flow channels 74 through which the heat medium flows as the temperature adjustment mechanism 66. A plurality of flow channels 74 extend in the direction of arrow X from the end face 64a of the material removal portion 64 and communicate with the appropriate (e.g., group-by-group) flow channels 68 of the shaped wall portion 62, respectively. The

flow passages

68, 74 of the molded wall portion 62 and the block wall portion 72 constitute a circulation circuit for circulating the heat medium, and function as a heat insulation function in a case where the heat medium is discharged from the flow passages 68, 74 (a vacuum state, a state where air stagnates). A plurality of flow channels 74 extend between the gap 60 and the hollow 70, respectively. Therefore, each flow channel 74 exerts a heat insulating effect on the surroundings, and suppresses temperature change, thereby flowing the heat medium.

The flow passage 74 of the block wall portion 72 communicates with the communication passage 76 of the movable mold 16 via the hole of the heat insulating plate 54. The communication passage 76 is connected to a pipe 78, and the pipe 78 communicates with a heat medium source 80 provided outside the movable mold 16. The heat medium source 80 has the following functions: the heat medium (heat medium, refrigerant) at an appropriate temperature is supplied to the

flow paths

68, 74 under the control of the controller 30, and the heat medium existing in the

flow paths

68, 74 is collected.

As shown in fig. 2, the nest 18 (the molding wall portion 62 and the material removal portion 64) has a plurality of holes 82 smaller than the hollow portion 70 in addition to the hollow portion 70. The plurality of apertures 82 can further improve the insulating properties of the nest 18. The location, number, shape, etc. of the holes 82 can be designed arbitrarily according to the shape and strength of the nest 18.

As shown in fig. 1, a tapered portion 84 for disposing the driven nest 50 is provided on the side wall 48 of the movable mold 16 and a part of the molding wall portion 62 of the nest 18. Driven nest 50 has the following functions: as the nest 18 thermally expands, displacement occurs, allowing the thermal expansion, thereby suppressing damage to the nest 18. In fig. 1, only the driven nest 50 is shown as being disposed between the movable die 16 and the nest 18 in the arrow Z direction, but the driven nest 50 is also preferably disposed between the movable die 16 and the nest 18 in the arrow Y direction.

The inclined surfaces formed by the tapered portion 84 and the driven nest 50 contact each other. The tapered end of the driven nest 50 is connected to the stepped portion of the movable mold 16 via the elastic member 86, while the tapered end of the driven nest 50 faces the runner 42 of the fixed mold 14. The driven nest 50 is formed of a material such as stainless steel having a lower thermal conductivity than the nest 18 and the movable mold 16.

Accordingly, the gap 60 between the side wall 48 and the material removal portion 64 (non-contact portion 58b) and the flow path 42 are always closed. That is, when the nest 18 thermally expands in the arrow Y-Z direction, the driven nest 50 slides along the inclined surface and is pushed out toward the flow path 42. Thus, the gap 60 is continuously closed from the flow passage 42 while allowing the nest 18 to thermally expand. On the other hand, when the nest 18 is cooled and contracted, the driven nest 50 slides along the inclined surface by the restoring force of the elastic member 86 and is pulled back to the elastic member 86 side. At this time, the driven nest 50 also contacts the movable mold 16 and the nest 18, and the gap 60 and the flow passage 42 are continuously closed.

The molding die 10 according to the present embodiment is basically configured as described above, and its operational effects will be described below.

The injection molding apparatus 12 having the molding die 10 is disposed at a position where the movable mold 16 and the fixed mold 14 are separated from each other before injection molding of a molded article. In this state, the controller 30 supplies a heat medium of a predetermined temperature (equal to or higher than the melting temperature of the molding material) to the flow path 68 of the nest 18 to heat the nest 18. The nest 18 thermally expands by this heating, but the stress of the thermal expansion is suppressed by the abutting portion 58a of the molded wall portion 62 coming into contact with the side wall 48 fixed to the movable die 16 and moving in and out from the driven nest 50 toward the flow passage 42.

After that, the controller 30 controls the driving of the movable actuator 28 to move the movable mold 16 toward the fixed mold 14 to perform mold clamping. By this mold clamping, the

partition surfaces

48a, 62a of the movable mold 16 and the nest 18 are brought into contact with the partition surface 36a of the fixed mold 14, and the cavity 20 is formed inside the

partition surfaces

48a, 62a of the movable mold 16 and the nest 18. In this state, although the nest 18 receives a pressing force between the fixed mold 14 and the movable mold 16, the material removed portion 64 has a suitable strength and supports the molding wall portion 62, and thus the shape of the cavity 20 can be favorably maintained.

As shown in fig. 3, in the nest 18, only the abutting portion 58a of the molding wall portion 62 is in contact with the side wall 48 of the movable mold 16, and a gap 60 is present between the non-abutting portion 58b of the material removed portion 64 and the side wall 48 of the movable mold 16, thereby being insulated. Further, since the heat insulating plate 54 is provided between the end surface 64a of the material removed portion 64 and the bottom wall 46 of the movable mold 16, heat dissipation from the nest 18 can be suppressed. In addition, the hollow portion 70 and the aperture 82 also improve the thermal insulation of the nest 18. Therefore, even if the heating of the temperature adjustment mechanism 66 is suppressed or stopped, the nest 18 can maintain a desired temperature well.

After the mold is closed, the injection molding apparatus 12 injects the molten molding material from the injection nozzle 34 of the injection mechanism 32 into the cavity 20 through the sprue 40, the runner 42, and the gate 44. After or during this injection, the control unit 30 supplies a refrigerant of a predetermined temperature or lower to the flow passage 68 of the nest 18 to cool the nest 18. Accordingly, the nest 18 shrinks due to the temperature drop.

At this time, the flow passage 74 in the block wall portion 72 is insulated by the hollow portion 70 and the hole 82 provided therearound. Therefore, the coolant is supplied to the flow channel 68 of the molded wall 62 while suppressing the temperature rise, and thus the nest 18 can be efficiently cooled.

When the temperature of the molding wall 62 is lowered, the injected molding material is solidified and molded into a molded article. When the temperature of the nest 18 reaches a predetermined temperature, the refrigerant is recovered from the

flow passages

68 and 74, and the movable mold 16 is moved in the direction of the arrow X2 to open the mold. After that, when the molded article is taken out by the ejector mechanism and injection molding is performed again, the same operation as described above is repeated.

As described above, according to the molding die 10 of the present embodiment, the movable die 16 and the nest 18 can be positioned satisfactorily by the contact portion 58a of the nest 18, and the cavity 20 can be formed with high accuracy. Further, by forming the gap 60 between the non-contact portion 58b of the nest 18 and the movable die 16 in the expanded state, the heat conduction between the nest 18 and the movable die 16 can be suppressed satisfactorily by the heat insulating effect of the gap 60. Further, since the nest 18 has the hollow portion 70, the hollow portion 70 also has a heat insulating effect. Therefore, the temperature change of the nest 18 can be suppressed, and energy for adjusting the temperature of the nest 18 can be saved at the time of injection molding. As a result, the manufacturing cost for manufacturing the molded article can be reduced.

In this case, the molding die 10 has the plurality of hollow portions 70, and thus the heat insulating effect of the nest 18 can be further improved. Further, since the abutting portion 58a is disposed in the vicinity of the opening of the housing space 16a, the molding die 10 can maintain the shape of the cavity 20 with higher accuracy. Further, since the gap 60 is formed in the entire circumferential direction of the inner circumferential surface of the movable mold 16 (the side wall 48), the heat insulating effect is increased, and thus the energy consumed for temperature adjustment of the nest 18 can be greatly reduced. In addition, the mold 10 can further suppress the conduction of heat to the movable mold 16 through the heat insulating plate 54.

Further, the nest 18 can easily change the temperature of the nest 18 itself through the

flow passages

68 and 74, and the

flow passages

68 and 74 can exhibit the heat insulating effect similar to the hollow portion 70 by discharging the heat medium. In particular, the molding wall 62 of the nest 18 can be smoothly adjusted in temperature by a heat medium with little temperature change, thereby providing an appropriate temperature to the molding material injected into the cavity 20. The temperature adjustment mechanism 66 can easily cool the nest 18 by flowing a refrigerant as a heat medium through the flow passage 68, and can favorably promote solidification of the molding material.

The present invention is not limited to the above-described embodiments, and various modifications can be made in accordance with the gist of the present invention. For example, the nest 18 may be provided not only on the movable mold 16 but also on the stationary mold 14.

Claims

1. A molding die (10) is characterized in that,

having a first die (16), a second die (14) and a nest (18), wherein,

the first mold (16) and the second mold (14) are closed;

the nest (18) being configured to the first mold (16),

the nest (18) being capable of forming a cavity (20) between it and the second mould (14) into which moulding material flows, and,

the nest (18) having an abutment portion (58a), a non-abutment portion (58b) and a hollow portion (70), wherein,

the contact portion (58a) is in contact with the first mold (16) in an expanded state due to temperature rise;

the non-abutting portion (58b) forming a gap (60) between it and the first die (16) without abutting in the expanded state;

the hollow part (70) extends from an end surface (64a) on the opposite side of the cavity (20) to the vicinity of the cavity (20) and is not communicated with the cavity (20),

the nest (18) has a flow channel (68, 74), the flow channel (68, 74) is used for the flow of the heat medium for adjusting the temperature of the nest (18),

the flow channel (68) is provided in a molding wall (62) that forms the cavity (20) at least at a position closer to the second mold (14) than the hollow portion (70),

the flow channel (74) is also formed to extend between the gap (60) and the hollow portion (70), and to communicate with a flow channel (68) provided in the molded wall portion (62).

2. A molding die (10) according to claim 1,

the nest (18) has a plurality of hollow portions (70) with a wall portion therebetween.

3. A molding die (10) according to claim 1,

the first mold (16) has a receiving space (16a) for receiving the nest (18),

the gap (60) is formed on the inner side of the storage space (16a) with respect to the contact portion (58a), and is formed over the entire circumferential direction of the inner circumferential surface constituting the storage space (16 a).

4. A molding die (10) according to claim 1,

a thermal insulating member (54) is disposed between the nest (18) and the first mold (16).

5. A molding die (10) according to claim 1,

the heat medium may comprise a refrigerant and,

the flow channels (68, 74) are designed as cooling means (66) for cooling the insert (18) during injection molding.

6. A molding die (10) according to claim 1,

the flow channels (68, 74) are grouped for each location of the nest (18) and enable the thermal medium to flow for each location.

7. A molding die (10) according to claim 1,

a driven nest (50) is provided in the first mold (16), the driven nest (50) partially closing the gap (60) and being configured to be displaceable as a separate member from the nest (18),

the driven nest (50) allows for thermal expansion and contraction of the nest (18) while continuously closing the gap (60).