JP2000233416A - Molding apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To mass-produce a non-foamed molded article by casting of a liq. molding material, to avoid complication of an apparatus and to make cleaning on every molding unnecessary. SOLUTION: This apparatus is provided with a casting nozzle 12 for a casting machine 1 for foaming and a vacuum chamber 4 hermetically surrounding the outer periphery of a butting part of a sprue 2a of a mold unit 2 butted to this. When molding is performed, at first, under a condition where the casting nozzle 12 and the mold unit 2 are separated from each other, the surroundings is hermetically sealed by the vacuum chamber 4 and when a vacuum chamber VS partitioned thereby is sucked by means of a vacuum pump 5, casting spaces 2b-2c, etc., in the mold unit and a high pressure head 11 of the casting machine 1 for foaming are drawn to a vacuum through the vacuum chamber VS and the molding material is evacuated. Thereafter, the mold unit 2 is hermetically butted with the casting nozzle 12 by means of a pressing and heating unit 3 and they are clamped to cast the molding material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding technique for molding a non-foamed resin molded article such as an elastic part for automobiles, an anti-vibration material and a cushion material by casting a liquid material.

[0002]

2. Description of the Related Art Conventionally, when molding is performed by casting a highly viscous molding material, such as rubber molding, for example.
Molding with a molding device having a poppet valve inside the mold is possible. That is, when the plasticized molding material is cast into the mold, the pressure of the molding material closes the poppet valve in the mold, and the material is confined in the mold and molded. However, in such a molding apparatus, when the liquid molding material is cast, its viscosity is low, so if the casting is not performed at a high speed, the liquid molding material will not be molded before the pressure for closing the poppet valve rises. It leaks out of the meeting surface. Further, in molding with a liquid molding material, if the air is not sufficiently degassed by evacuation, bubbles will be formed in the molded product, so that it is difficult to perform non-foam molding.

[0003] In particular, for example, urethane products,
In the case of gelling and non-foaming molding by mixing two types of liquid materials, at the laboratory level, air bubbles in the molding material are removed by mixing and uniformly stirring the two liquid materials in a vacuum chamber. It is possible to perform non-foaming molding by casting it in a vacuum-evacuated mold. However, it is pointed out that the apparatus is complicated and large-scaled in order to be able to mass-produce this. Moreover, a liquid molding material for molding urethane or the like generally has a property of curing by reacting with moisture in the air, that is, since the liquid molding material attached to a mold surface or the like is cured, a stirring / mixing container is required. In addition, it is necessary to clean the mold.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has as its technical object the mass production of a non-foamed molded product by casting a low-viscosity liquid molding material. It is an object of the present invention to provide a molding apparatus which does not require complicated cleaning and does not require cleaning for each molding.

[0005]

As a means for effectively solving the above-mentioned technical problems, a molding apparatus according to the present invention comprises a mold unit into which a liquid molding material is cast from a head of a casting machine. A pressurizing / heating unit that clamps and heats the sprue of the mold unit against the casting nozzle at the tip of the head, and an abutting position between the mold unit and the casting nozzle. The vacuum chamber includes a vacuum chamber that seals an outer peripheral space to define a vacuum chamber, and a valve device that selectively connects the vacuum chamber to a vacuum pump or an atmosphere open side. With such a configuration, the inside of the casting space of the mold unit and the inside of the head of the casting machine can be degassed by vacuuming through the vacuum chamber, and can be subjected to non-foaming molding.

As another means for effectively solving the above-mentioned technical problem, instead of the vacuum chamber in the above-described configuration, the mold is abutted to a mold unit at the time of mold clamping and connected to a vacuum pump inside. A vacuum case in which a vacuum chamber is defined, and a valve device that is opened at an abutting portion between the mold unit and the vacuum case and opens and closes a vent that communicates the vacuum chamber with a casting space of the mold unit. Also in the configuration, the inside of the casting space of the mold unit and the inside of the head of the casting machine can be similarly evacuated.

[0007]

1 to 4 show a first embodiment of a molding apparatus according to the present invention. That is, this molding apparatus is for molding a urethane product having rubber-like elasticity by, for example, mixing isocyanate (urethane prepolymer + plasticizer) which is a liquid molding material and a polyol and casting the mixture in a mold. As shown in FIG. 1, a mold unit 2 into which the above two types of liquid molding materials are cast from a foaming casting machine 1 and a sprue (described later) of the mold unit 2 are attached to the foaming casting machine. A pressurizing / heating unit 3 that clamps and heats a mold while being brought into contact with a casting nozzle (described later) of the machine 1, a vacuum chamber 4 that defines a vacuum chamber VS around the mold unit 2, Vacuum pump 5 for chamber VS
Alternatively, a vacuum valve 6 selectively connected to the atmosphere open side is provided.

The foam casting machine 1 has a known structure including a degassing device for degassing a material piping system and a material tank by a vacuum pump and an internal cleaning mechanism (not shown). A table 13 and a high-pressure head 11 fixedly installed on a top plate 13a are provided. A casting nozzle 12 protruding from the tip (lower end) of the high-pressure head 11 penetrates the top plate 13a downward.

The mold unit 2 includes a movable plate 21, a lower mold 22, and a middle mold 2, which are arranged on the movable plate 21 in order.
3, consisting of an upper mold 24 and an I mold 25. The uppermost I-type 25 is provided with a sprue 2a, which is a connection portion with the casting nozzle 12 of the foaming casting machine 1, and is formed between the I-type 25 and the upper die 24 disposed thereunder. The sprue 2 between the joints
a, a plurality of cavities 2c that are molding cavities astride the upper mold 24, the middle mold 23 and the lower mold 22 via the runner 2b.
Are formed. As shown in FIG. 2, a part of the mold unit 2 is shown in an enlarged manner, and a material escape portion 2d is formed at an end of the runner 2b.

The outer peripheral portions of the abutment surfaces (parting surfaces) of the respective dies 22 to 25 in the die unit 2 are sealed via O-rings 26 in the illustrated combined state.
The abutting surface between the sprue 2 a and the casting nozzle 12 is sealed via an O-ring 27.

The pressurizing / heating unit 3 includes an output rod 31
a, a pressurizing cylinder 31 protruding vertically upward, and a central portion at the upper end of the output rod 31a, a spherical washer (not shown).
A heat insulating plate 32 mounted via a floating joint 31b, a heating plate 33 mounted on the heat insulating plate 32 and incorporating a heater (not shown), and a protection plate 34 mounted on the heat plate 33 The heat insulating plate 32, the hot platen 33, and the protective plate 34 are integrally moved up and down by driving the pressurizing cylinder 31 (output rod 31a). The mold unit 2 is positioned and set on the protective plate 34 from outside the apparatus by a mold unloading mechanism (not shown).

The pressurizing / heating unit 3 includes a guide plate 35 fixed to the upper end of the cylinder body of the pressurizing cylinder 31, and a plurality of vertical portions via bearings 35a at a plurality of locations on the outer peripheral portion of the guide plate 35. A guide rod 36 is inserted so as to be reciprocally movable in the direction, and the upper end of each guide rod 36 is fixed to the outer peripheral portion of the heat insulating plate 32 via a flange 36a. Thus, the heat insulating plate 32, the hot platen 33 and the protection plate 34
Is guided and the rotation is stopped.

The vacuum chamber 4 comprises a top plate 4a and side walls 4b extending downward from the outer periphery of the top plate 4a. That is, the vacuum chamber 4 has a case shape in which the lower end is open. It is arranged movably. A plurality of coil springs 41 are interposed between the outer peripheral portion of the upper surface of the top plate 4a of the vacuum chamber 4 and the top plate 13a of the mounting base 13.

An opening 4c is formed in the center of the top plate 4a of the vacuum chamber 4, and a casting nozzle 12 protruding from the lower end of the high-pressure head 11 of the foaming casting machine 1 closes the opening 4c. Penetrates downward. In addition, the opening 4c is slidably in close contact with the outer peripheral surface of the casting nozzle 12.
A ring 42 is mounted.

The vacuum chamber 4 includes a pressurizing / heating unit 3
Lower mold 2 of mold unit 2 set on protective plate 34
2, a volume capable of surrounding the middle mold 23, the upper mold 24, and the I-form 25, and the lower end edge of the side wall 4b is more peripheral than the outer surfaces of the lower mold 22, the middle mold 23, the upper mold 24, and the I-form 25; The vacuum chamber VS is defined by closely contacting the upper surface of the outer peripheral portion of the movable plate 21 projecting to the side via the O-ring 43. In this close state, the pressurizing cylinder 31 of the pressurizing / heating unit 3 causes the mold unit 2
The sprue 2a formed on the upper surface of the I-type 25 in the mold unit 2 is moved up and down together with the vacuum chamber 4 to a predetermined height, as shown in FIG. The lower surface of the casting nozzle 12 is closely abutted.

The vacuum chamber V defined by the vacuum chamber 4
S can be evacuated by a vacuum pump 5 arranged outside. To describe this in more detail, a vacuum pipe 51 opened to the vacuum chamber VS is attached to the top plate 4a of the vacuum chamber 4, and the vacuum pipe 51 is attached to the top plate 13a of the mounting base 13 of the foam casting machine 1. Opened hole 13
b, a vacuum pipe 52 extending from the suction port of the vacuum pump 5 to the outside, and a vent pipe 5 open to the atmosphere.
3 is selectively switched and connected via a vacuum valve 6.

More specifically, the vacuum valve 6 has a shut-off section 61, a vacuum connection section 62, and an atmosphere opening section 63, and these sections 61 to 63 are provided with solenoid ON / OF.
By F, it is selectively moved to the connection position with the vacuum pipes 51, 52 and the ventilation pipe 53. That is, when the connection position is in the cutoff section 61, the vacuum pipe 51 is cut off from the vacuum pipe 52 and the ventilation pipe 53, and the connection is made to the vacuum connection section 6.
2, the vacuum pipe 51 is connected to the vacuum pipe 52.
When the connection is switched to the open-to-atmosphere section 63, the vacuum pipe 51 is connected to the ventilation pipe 53 and the vacuum pipe 52 is shut off.

According to the molding apparatus of the first embodiment,
The molding operation is performed as follows. First, as shown in FIG. 3, the pressurizing / heating unit 3 includes a pressurizing cylinder 3
1, the heat insulating plate 32, the hot platen 33, and the protective plate 34 have been lowered to their lower movement limit positions, and the moving plate 21, the lower mold 22, the middle mold 23, the upper mold 24, and the I mold 25 in the mold unit 2 They are combined in a vertically stacked state outside the molding apparatus, and are positioned and set on the protection plate 34 by a mold unloading mechanism (not shown). Each mold 22 to 25 of the set mold unit 2 is pressurized and
Heating is performed by the heating platen 33 of the heating unit 3 via the protection plate 34 and the moving plate 21, and the molding material is maintained at an appropriate temperature required for a thermosetting reaction.

Next, the mold unit 2 is moved upward by driving the pressurizing cylinder 31 of the pressurizing / heating unit 3 so that the output rod 31a projects vertically upward by application of hydraulic pressure. At this time, the upward movement of the mold unit 2 is performed by reciprocating the guide plate 35 fixed to the pressurizing cylinder 31 and the outer peripheral portion of the heat insulating plate 32 in the vertical direction via the bearing 35a on the outer peripheral portion of the guide plate 35. Guide rod 36 movably inserted
Thus, the guide is guided through the heat insulating plate 32, the hot platen 33, and the protective plate 34, and the rotation about the floating joint 31b is prevented.

In the process of raising the mold unit 2 described above,
The upper surface of the outer peripheral portion of the moving plate 21 is in close contact with the lower end surface of the side wall 4b of the vacuum chamber 4 via the O-ring 43 and pushes it up, so that the vacuum chamber 4 also rises together with the mold unit 2 at that point. The rising operation at this time is performed when the state shown in FIG. 1 is reached, that is, the upper surface of the I-type 25 in the mold unit 2 is spaced from the lower surface of the casting nozzle 12 of the foaming casting machine 1 by several mm. Stops once it reaches the adjacent height via.

When the upward movement of the mold unit 2 is stopped in the state shown in FIG. 1, the connection of the vacuum valve 6 is changed to a vacuum connection portion 62.
And the vacuum chamber 4 driven by the vacuum pump 5
Forcibly exhaust (evacuate) the inside. In the vacuum chamber 4 (vacuum chamber VS), a contact portion between the lower end of the side wall 4b and the movable plate 21 is sealed by an O-ring 43, and a gap between the opening 4c and the outer peripheral surface of the casting nozzle 12 penetrating therethrough. O-ring 42
, The degree of vacuum is increased by the forced evacuation.

At this time, the sprue 2a of the mold unit 2
Are separated from the casting nozzle 12,
a and the casting nozzle 12 are open to the vacuum chamber VS. Therefore, the runner 2 which is a casting space in the mold unit 2 is
b, the cavity 2c, the material release portion 2d, and the inside of the high-pressure head 11 of the foaming casting machine 1 are also evacuated through the vacuum chamber VS.

The isocyanate, which is a liquid molding material for urethane molding, is cured by reacting with water vapor in the air. However, the inside of the high-pressure head 11 of the foaming casting machine 1 is evacuated as described above. Accordingly, it is possible to effectively prevent the liquid molding material from being cured by steam in the high-pressure head 11. In addition, bubbles generated in the liquid molding material in the high-pressure head 11 are also effectively degassed.

When the degree of vacuum in the vacuum chamber VS reaches a predetermined level, the mold unit 2 and the vacuum chamber 4 are again raised by the pressurizing cylinder 31. Then, as shown in FIG. 4, the sprue 2 on the upper surface of the
When "a" comes into close contact with the lower end of the casting nozzle 12 of the foaming casting machine 1 via the O-ring 27, the lifting operation by the pressurizing cylinder 31 is stopped. Note that the vacuum state in the vacuum chamber VS can be maintained by switching the connection of the vacuum valve 6 to the shut-off unit 61. Since the load from the mold unit 2 is received from the vacuum chamber 4 by the mounting base 13 via the coil spring 41, the load by the pressurizing cylinder 31 is concentrated on the abutting portion between the sprue 2a and the casting nozzle 12. Can be prevented.

After the mold has been clamped as described above, a predetermined amount of the liquid molding material is poured from the foaming casting machine 1 into the mold unit 2, and the respective cavities 2c are passed through the runner 2b and the gate 2d. Is filled. At this time, since the inside of the runner 2b, the cavity 2c, and the material release portion 2d, which are the casting space of the mold unit 2, are in a state of being evacuated as described above, the casting is quickly performed. In addition, no bubbles are mixed into the liquid molding material.

The cast liquid molding material receives heat from the mold unit 2 heated by the hot platen 33 of the pressurizing / heating unit 3 and undergoes a hardening reaction with time. And
The cured portion of the molding material in the cavity 2c is the product.

After a predetermined time required for curing (forming) the molding material has elapsed, the pressure cylinder 31 of the pressure / heating unit 3 is operated in the direction of releasing the mold clamping, that is, in the direction of lowering the output rod 31a. As a result, the mold unit 2 moves downward, and the sprue 2 a of the I-type 25 is separated from the casting nozzle 12 of the foaming casting machine 1.

When the mold unit 2 starts lowering, the vacuum chamber 4 also lowers accordingly. At this time, the vacuum valve VS is switched to the atmosphere opening section 63 so that the inside of the vacuum chamber VS is connected to the pipe 5. Since the vacuum chamber 4 and the moving plate 21 are released from the vacuum state and the suction state is released, the moving plate 21 is moved from the vacuum chamber 4 when the vacuum chamber 4 reaches the lower movement limit position. When released, the mold unit 2 descends to the lower movement limit position shown in FIG. And the mold unit 2 descended to the lower limit position of movement
Is moved to the outside of the molding apparatus by a mold unloading mechanism (not shown), the mold is opened, and the molded product is released.

When the above-described series of molding steps is completed, a cleaning operation for removing the cured molding material adhered to the mold unit 2 is performed as necessary. The foaming casting machine 1 has an internal cleaning mechanism. Therefore, the cleaning operation only needs to be performed on the mold unit alone.

Next, FIG. 5 shows a second embodiment of the molding apparatus according to the present invention. In the molding apparatus according to this embodiment, as shown in FIG. 1, the configurations of a foaming casting machine 1, a mold unit 2, and a pressurizing / heating unit 3 are substantially the same as those of the above-described first embodiment. The configuration for vacuuming the inside of the high-pressure head 11 and the inside of the mold unit 2 of the foaming casting machine 1 is different.

That is to say, this will be described in detail. The lower surface of the top plate 13a of the mounting base 13 in the foam casting machine 1 is
A vacuum case 7 is hermetically mounted via an O-ring 71, and a vacuum chamber VS ′ defined by the vacuum case 7 is a vacuum pipe mounted through the top plate 13 a of the mounting base 13. It is connected to the suction port of the vacuum pump 5 via 51. The outer periphery of the upper surface of the uppermost I-type 25 in the mold unit 2 is pressed by the pressurizing / heating unit 3 into the casting nozzle 12 of the foaming casting machine 1.
When the sprue 2a rises to the height at which the sprue 2a abuts (the upper limit of the movement), the sprue 2a is abutted against the bottom of the vacuum case 7.

A vent hole 7a is formed at the bottom of the vacuum case 7 at an abutting position with the I-type 25. The I-type 25 communicates with the runner 2b in the mold unit 2 and has a valve seat 25a '. Vent holes 25a are provided corresponding to the vent holes 7a. Also, the mounting table 1 of the foaming casting machine 1
A poppet valve 8 whose axis is vertical is inserted through the top plate 13a of the third concentrically from the outside concentrically with the vent hole 7a. The poppet valve 8 is reciprocated in the axial direction (vertical direction) by an external actuator (not shown), and as shown in a partially enlarged view in FIG. The surface 8a enters the I-shaped air hole 25a at the upper limit of the movement from the air hole 7a, and closes and closes the valve seat 25a '.

The insertion portion of the poppet valve 8 in the top plate 13a of the mounting base 13 is sealed by an O-ring 14, and the insertion portion of the vacuum pipe 51 is sealed by an O-ring 15. Further, a gap formed on the outer periphery between the ventilation holes 7a and 25a when the upper surface of the I-type 25 abuts against the bottom of the vacuum case 7 is sealed by an O-ring 28.

On the lower surface of the top plate 13a of the mounting base 13, a required number of stopper blocks 9 are arranged on the outer periphery of the casting nozzle 12. The stopper block 9 has the same height as the vacuum case 7 and
The bolt 3a is vertically movably supported by a predetermined distance by a bolt 91 screwed from below, and is elastically urged downward by a coil spring 92. Accordingly, when the mold unit 2 is at a position separated downward from the casting nozzle 12 as shown in FIG. 6 (A), the stopper block 9 projects downward from the lower surface of the vacuum case 7. It is in.

According to the molding apparatus of the second embodiment,
The molding operation is performed as follows. First, the pressurizing / heating unit 3 uses a pressurizing cylinder 31 to
The hot platen 33 and the protection plate 34 have been lowered to their lower movement limit positions. The mold unit 2 composed of the moving plate 21, the lower mold 22, the middle mold 23, the upper mold 24, and the I mold 25 is combined with each other in a vertically stacked state outside the molding apparatus, and a mold not shown in and out. It is set on the protection plate 34 by a mechanism.

At this time, the protection plate 34 and the mold unit 2 are positioned with respect to each other via a rocket pin or the like (not shown). Also, the set mold unit 2
Each of the molds 22 to 25 is a hot platen 33 of the pressurizing / heating unit 3.
Thus, the molding material is constantly heated via the protection plate 34 and the moving plate 21, and is maintained at an appropriate temperature required for the thermosetting reaction of the molding material.

Next, the mold unit 2 is moved upward by driving the pressurizing cylinder 31 of the pressurizing / heating unit 3 so that the output rod 31a projects vertically upward by application of oil pressure. Then, as shown in FIG. 5, the sprue 2a on the upper surface of the I-type 25 in the mold unit 2 comes into close contact with the lower end of the casting nozzle 12 of the foaming casting machine 1 via the O-ring 27, as shown in FIG. When the outer periphery of the upper surface of the I-type 25 comes into close contact with the bottom of the vacuum case 7 via the O-ring 28, the operation is stopped.

In the above-described mold raising process, the lower surface of the stopper block 9 which has been projected downward from the lower surface of the vacuum case 7 as shown in FIG. The stopper block 9 comes in contact with the upper surface of the I-type 25 of the unit 2 and thereafter rises together with the mold unit 2 while compressing the coil spring 92. Then, the sprue 2 a is connected to the casting nozzle 12 via the O-ring 27.
At the same time that the outer periphery of the upper surface of the I-type 25 is closely abutted with the bottom of the vacuum case 7 via the O-ring 28, and the stopper block 9 is The mold unit 2 contacts the lower surface of the plate 13a.
Therefore, it is possible to prevent the load of the pressurizing cylinder 31 from being concentrated on the abutting portion between the sprue 2a and the casting nozzle 12.

The mold unit 2 includes a pressing cylinder 3
1 and a guide rod 36 fixed to the outer peripheral portion of the heat insulating plate 32 and inserted through the outer peripheral portion of the guide plate 35 via a bearing 35a so as to be vertically reciprocally movable. , Is prevented from rotating through the hot platen 33 and the protection plate 34, and is positioned on the protection plate 34. Therefore, when the I-type 25 and the vacuum case 7 abut against each other, the ventilation holes 7a, 25
a are connected to each other. Also, the ventilation holes 7a, 2
The gap formed between 5a is sealed by O-ring 28.

Next, the vacuum case 7 is
Forcibly exhaust (evacuate) the inside. At this time, as shown in FIG. 5, since the poppet valve 8 is at the upper limit position of its movement and the vent holes 7a and 25a are open, the forced exhaustion causes the vacuum chamber VS 'in the vacuum case 7 to be closed. As the degree of vacuum increases, the runner 2b, the cavity 2c, and the material release portion 2d, which are the casting space in the mold unit 2, are also evacuated through the vacuum chamber VS ',
Further, the interior of the high-pressure head 11 of the foaming casting machine 1 in a state of being in communication with the runner 2b is also evacuated via the casting nozzle 12 closely contacted with the sprue 2a, and the degree of vacuum is increased. go. For this reason, the hardening of the liquid molding material in the high-pressure head 11 is effectively prevented, and the bubbles generated in the molding material are also effectively degassed.

When the inside of the vacuum case 7 reaches a predetermined degree of vacuum, as shown in FIG. 6B, the poppet valve 8 is lowered by an external actuator (not shown).
The lower end tapered surface 8 a is
a into the ventilation hole 25a of the mold unit 2 from the
5a 'and the valve is closed.

The vent holes 7a, 25a are opened by the poppet valve 8.
Is closed, a predetermined amount of the liquid molding material is poured into the mold unit 2 from the foaming casting machine 1. At this time, since the inside of the runner 2b, the cavity 2c, and the material release portion 2d, which are the casting spaces of the mold unit 2, are in a evacuated state as described above, the casting is quickly performed, In addition, no bubbles are mixed into the liquid molding material. The cast liquid molding material receives a heat from the mold unit 2 heated by the hot platen 33 of the pressurizing / heating unit 3 and undergoes a hardening reaction with time.

After a predetermined time required for curing (molding) the liquid molding material in the mold has elapsed, the pressure cylinder 31 of the pressure / heating unit 3 is operated in the mold release direction. As a result, the mold unit 2 moves downward, and the sprue 2 a of the I-type 25 is separated from the casting nozzle 12 of the foaming casting machine 1. And the mold unit 2 descended to the lower limit position of movement
Is moved to the outside of the molding apparatus by a mold unloading mechanism (not shown), the mold is opened, and the molded product is released.

After the above-described series of steps is completed, a cleaning operation for removing the hardened molding material adhered to the mold unit 2 is performed. However, since the foaming casting machine 1 has an internal cleaning mechanism, The cleaning operation need only be performed on the mold unit alone.

[0045]

As is apparent from the above description, according to the molding apparatus of the present invention, the inside of the mold unit and the inside of the head of the casting machine have the vacuum chamber which is brought into contact with the mold unit at the time of mold clamping. Since the air is evacuated through the air, air bubbles in the molding material can be surely degassed and non-foaming molding can be performed. Moreover, since it is not necessary to provide a vacuuming mechanism in the casting machine itself, the apparatus can be made inexpensive, and the cleaning operation after molding can be performed only on the mold unit.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a state of a vacuum chamber in a first embodiment of a molding apparatus according to the present invention at the time of evacuation.

FIG. 2 is an explanatory diagram showing an enlarged part of a cross section of a mold unit in the molding apparatus of the embodiment.

FIG. 3 is an explanatory diagram showing a state where a mold unit is separated downward from a vacuum chamber in the embodiment.

FIG. 4 is an explanatory diagram showing a mold clamping state in the embodiment.

FIG. 5 is an explanatory view showing a second embodiment of the molding apparatus according to the present invention.

FIG. 6 is a partially enlarged view of the second embodiment, in which (A) shows a state in which the mold unit is separated from the casting nozzle and the vacuum case, and (B) shows a state in which the mold unit is cast. It is explanatory drawing which shows the state which joined the nozzle and the bottom part of a vacuum case.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Foaming casting machine 11 High-pressure head 12 Casting nozzle 13 Mounting stand 14, 15, 26, 27, 28, 42, 43, 71 O
Ring 2 Mold unit 2a Sprue 2b Runner 2c Cavity 2d Material escape part 21 Moving plate 22 Lower die 23 Middle die 24 Upper die 25 I-type 25a Vent hole 25a 'Valve seat 3 Pressurizing / heating unit 31 Pressurizing cylinder 32 Heat insulating plate 33 Heating plate 34 Protective plate 35 Guide plate 36 Guide rod 4 Vacuum chamber 41,92 Coil spring 5 Vacuum pump 51,52 Vacuum pipe 53 Vent pipe 6 Vacuum valve 61 Shut off part 62 Vacuum connection part 63 Atmospheric release part 7 Vacuum case 7a Vent hole 8 Poppet valve 9 Stopper block 91 Bolt VS, VS 'Vacuum chamber

Continued on front page F term (reference) 4F204 AA31 AA45 AC05 AH15 AH26 AM28 EA03 EB01 EE01 EE06 EE10 EK09 EK13 4F206 AA31 AA45 AC05 AH15 AH26 AM28 JA01 JL02 JM03 JM04 JN26 JN43 JQ81 JQ90

Claims (2)

[Claims] 1. A mold unit (2) into which a liquid molding material from a head (11) of a casting machine (1) is cast, and a sprue (2a) of the mold unit (2) is attached to the head (2). 11) a pressurizing / heating unit (3) for clamping and heating in a state of being abutted against the casting nozzle (12) at the tip, and the mold unit (2) and the casting nozzle (12). A vacuum chamber (4) for sealing a space around an abutment position to define a vacuum chamber (VS), and a valve device for selectively connecting the vacuum chamber (VS) to a vacuum pump (5) or an atmosphere open side. (54). A molding apparatus comprising: 2. A mold unit (2) into which a liquid molding material from a head (11) of a casting machine (1) is cast, and a sprue (2a) of the mold unit (2) is attached to the head (2). 11) a pressurizing / heating unit (3) for clamping and heating in a state in which the mold is brought into contact with the casting nozzle (12) at the tip of the tip; A vacuum case (6) defining a vacuum chamber (VS ') connected to a vacuum pump (5); and a vacuum chamber (6), which is opened at an abutting portion between the mold unit (2) and the vacuum case (6). A valve device (55) for opening and closing the ventilation holes (6a, 25a) communicating the chamber (VS ') with the casting spaces (2b to 2d) of the mold unit (2). Molding equipment.