JP3126744B2 - Gate seal injection molding apparatus and injection molding method using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection molding apparatus and an injection molding method using the same, and more particularly to an injection molding apparatus suitable for injection molding of an optical element such as a plastic lens and an injection molding method using the same.

[0002]

2. Description of the Related Art In recent years, due to the high precision of plastic molding, various injection moldings utilizing the advantages of molding (molding), for example, injection molding of plastic lenses such as aspherical lenses (optical elements) have been made. . In this type of molding apparatus, since it is required to reduce the molding time per molded article to reduce the cost, for example, JP-A-1-139231 and JP-A-2-38012.
As described in Japanese Patent Application Laid-Open Publication No. H10-209, there is an apparatus in which a plurality of mold units are used so that one mold can be opened to another mold before the mold is opened and a molded product is taken out.

On the other hand, in molding a lens or the like having a large thickness and a large thickness deviation ratio, in order to enhance the accuracy of shape transfer by a molding die, an appropriate amount of resin is used just before the filling of the cavity is completed until the filling resin solidifies. It is necessary to keep applying pressure. Therefore, for example, a molding method in which a gate is sealed as described in JP-A-64-36421.
A law has been proposed.

[0004] In this method, in order to eliminate the non-uniformity of the resin pressure and the resin temperature caused by the resin orientation and pressure distribution as shown in FIG. 12, the mold is heated by a mold as shown in FIG. The temperature is raised above the glass transition point to perform injection filling, the gate is sealed and the flow of the resin is stopped, and then the resin is relaxed by keeping the mold at a temperature above the glass transition point, and the inside of the cavity is relaxed. The pressure and temperature of the resin are made uniform, and then the resin is slowly cooled slowly until the temperature becomes equal to or lower than the heat distortion temperature, and the molded product is taken out when the resin pressure becomes 0 (kgf / cm ² ).

[0005]

However, this is not the case.
In the molding in which the gate is sealed as described above, there is a problem that the molding cycle becomes longer due to the slow cooling and the productivity is reduced. In the case of using multiple mold units to shorten the molding cycle, a predetermined pressure cannot be continuously applied until the resin solidifies, so that satisfactory molding accuracy is secured. I couldn't.

The present invention has been made in view of such conventional problems, and has as its object to provide an injection molding apparatus and an injection molding method having high-accuracy transferability and high productivity. I do.

[0007]

In order to achieve the above object, according to the first aspect of the present invention, each unit has a pair of molds each having a cavity formed therein, and the pair of molds are connected to each other in a mold clamping direction. A plurality of cavity units consisting of a self-holding mechanism that self-holds the force of the cavity unit, a predetermined heating station, a filling / relaxation station,
Conveying means for conveying in the order of the slow cooling station and the molded article taking-out station, heating means provided in the heating station for heating the cavity unit to a temperature equal to or higher than the glass transition point, and heating means provided in the filling / relaxation station and heated by the heating means an injection filling means for injecting the molten resin through the gate portion into the cavity unit, each cavity
Is installed to move under the resin pressure
Sealing means having a moving valve body , cooling means provided at the slow cooling station for gradually cooling the cavity unit, and a molded product solidified in the cavity unit provided at the molded product removal station and taken out of the cavity unit. And a self-holding unit.
Mechanism to maintain the mold clamping force in the cavity unit
When the molten resin is injected and filled by the injection filling means
To the movable valve body which has received the resin pressure on the cavity side.
Therefore, the gate portion of the cavity unit is sealed .

According to a second aspect of the present invention, the injection filling means comprises an injection molding machine, a die positioning jig is provided on a die plate of the injection molding machine, and a heater for keeping heat is provided. The invention according to claim 3 is characterized in that the cavity unit located at the filling / relaxation station is provided with a pressing means for applying a pressing force in a direction orthogonal to a mold clamping direction. It is.

According to a fourth aspect of the present invention, in the injection molding apparatus of the first aspect, the moving valve body of the gate sealing means is provided.
Is formed in the gate portion forming groove of the mold of the cavity unit.
It is a spherical valve body provided so as to be movable . According to a fifth aspect of the present invention, in the injection molding apparatus of the first aspect, each of the cavity units arranges the self-holding mechanism in the vicinity of a mold piece having a transfer surface of a mold constituting the cavity unit. It is characterized by doing.

Further, according to the invention described in claim 6 , the injection
An injection molding method using a molding apparatus , wherein when a cavity unit is gradually cooled in a slow cooling station, 5 ° C /
The cooling is performed at a cooling rate of not more than one minute, and the resin in the cavity unit is cooled to a heat deformation temperature or less.

[0011]

According to the first aspect of the present invention, when the molten resin is filled into the cavity unit heated to a temperature equal to or higher than the glass transition point by the injection filling means, and the gate of the cavity unit is sealed by the gate sealing means, the cavity is closed. The unit alone can maintain the resin temperature and the resin pressure by itself. Therefore, the cavity unit is conveyed from the filling / relaxation station to the slow cooling station and gradually cooled by the cooling means. During this time, the other cavity units can be injected and filled with the molten resin, thereby improving the productivity.
Further, since the resin temperature and the resin pressure are appropriately maintained, the molding accuracy is improved. Also, check the resin pressure on the cavity side.
Since it is used for sealing, gates can be used even at high filling pressures.
Moving valve body of gate sealing means while sealing is reliable
Can be handled integrally with the cavity unit,
Work can be facilitated.

According to the third aspect of the present invention, since the pressing means applies a pressing force to the cavity unit in a direction orthogonal to the mold clamping direction, high-pressure resin is applied between the mold piece and the mold plate of the cavity unit. Intrusion is prevented, and deformation of the mold piece is also prevented. In the invention according to claim 4,
The moving valve element is the gate unit forming groove of the mold of the cavity unit.
Because it is a spherical valve body that is provided so that it can move
Sealing can be performed, and an effective pressure holding state can be ensured without depending on the pressure holding of the injection molding machine.

According to the fifth aspect of the present invention, since the self-holding mechanism is disposed near the mold piece, an effective mold clamping force can be obtained even after the injection molding machine is opened. In addition, 請
In the invention according to claim 6 , since the cavity unit is gradually cooled at a cooling rate of 5 ° C./min or less to a heat deformation temperature or less, uneven cooling is prevented, and high quality without deformation such as sink marks. Can be obtained.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 to 11 show a projection according to the first to fifth aspects of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows one Example of an out-molding apparatus , and has shown the example which applied this invention to shaping of the lens which is an optical element. First, the configuration will be described.

In FIG. 1 to FIG. 4, reference numeral 10 denotes a plurality of cavity units.
It comprises a pair of upper and lower molds 11, 12 which form a cavity 10a of a predetermined shape inside. The upper and lower molds 11 and 12 are composed of lens mirror pieces 11a and 12a (mold pieces), gate pieces 11b and 12b and input pieces 11c and 12c, and two mold plates for attaching the pieces.
It is divided into 11d, 11e and 12d, 12e, which form a strip-shaped cavity 10a as shown in FIG. In addition, the upper and lower molds 11 and 12
A groove-shaped concave portion (not shown) is formed in the peripheral portion of the transfer surfaces a and 12a, and a plurality of ribs R are formed at the ridge portion of the cavity 10a.

The plurality of cavity units 10 are conveyed by conveying means 90 such as a chain, heated at a predetermined heating station 20, and then charged at a filling / relaxation station.
Sent to 30, the filling-relieving station 30 is injected the molten resin into the cavity 10a while being gate seal is relaxed and the temperature and pressure, and then is transported to the annealing station 40 heat distortion temperature or less Gradually cooled to
At the part removal station 50, the mold is opened for removal of the part.

The heating station 20 is a place for quickly heating the cavity unit 10 with uniform heat, and includes a plurality of mold heating devices 21A, 21B, 21C as heating means. As shown in FIGS. 5 and 6, the mold heating device 21A
To 21C are copper materials having good thermal conductivity (heat conductivity 3
32 kcal / mh ° C.) and a pair of L-shaped heater blocks 22, 23,
Multiple sets of rod heaters 24 and thermocouples 25 embedded in 23
A clamping means 26 of a general clamp type, which is fixed upright on a substrate 27 together with the lower heater block 22, and a plurality of bolts 28A, 28B to form an upper heater block 23.
And a heater block retainer 29 connected to the heater block holder 29. Then, the tension lever part 262 of the fastening means 26
Is rotated, the cavity unit 10 inserted in the space between the heater blocks 22 and 23 is clamped, or the clamped state is released. Also, a heater controller (not shown) cooperates with the thermocouple 25 to manage the calorific value of the rod-shaped heater 24. In both figures, reference numeral 261 denotes a stand portion of the tightening means 26, 263 denotes a pressing plate interposed between the tension lever portion 262 and the heater block presser 29, and 291 and 292.
, 293 and 271 are heat insulating plates, and 231 and 232 are relative rotation stoppers between the heater blocks 22 and 23 attached to the heater block 23.

The fastening means 26 serves to shorten the time for heating the cavity unit 10 and for increasing the temperature. That is, as shown in FIG.
The heating / heating time varies significantly depending on the degree of adhesion between 22 and 23, and the heating time of the cavity unit 10 can be shortened by heating while generating a strong fastening force by the fastening means 26.

In the heating method of the present embodiment, for example, the mold heating device 21A, which is the first heating stage, is set slightly higher than the target temperature (the temperature at the time of injection), and then the second and third heating stages are performed. A step heating method of uniformly heating the cavity unit 10 stepwise by the mold heating devices 21B and 21C as stages was adopted. Further, the shape of the heater blocks 22 and 23 does not necessarily have to be L-shaped, and heating from four directions (four-sided heating) may be performed. The material of the heater blocks 22 and 23 may be replaced with the above-described copper material. For example, an aluminum material having good heat conductivity can be used. Further, the tightening method of the tightening means 26 can obtain a sufficient tightening force by any power such as hydraulic pressure or air pressure.

In the filling / relaxation station 30, a resin is injected and filled into the cavity 10a of the cavity unit 10 at a high pressure, and a ball-shaped moving valve 13 (gate sealing ) as shown in FIGS. Means) seals the gate of the cavity unit 10 to reduce uneven distribution of the resin temperature and pressure after filling. The injection / filling operation is performed by a known injection molding machine 60 (injection filling means) at a high pressure of, for example, 1000 kgf / cm ² or more. Die plate of this injection molding machine 60
As shown in FIG.
Are mounted, and die positioning jigs 65 and 66 for positioning the cavity unit 10 at predetermined positions are attached to the die plate 62.

The filling / relaxation station of the present embodiment
9, the pressing unit 71 including the hydraulic cylinder 71a and the contact member 71b also tightens the cavity unit 10 in a direction orthogonal to the mold clamping direction as shown in FIG. This prevents the cavity unit 10 from being deformed so as to open in the orthogonal direction during injection filling. When such deformation occurs, a gap is generated between the lens mirror pieces 11a, 12a constituting the cavity unit 10 and the mold plates 11e, 11d, 12d, 12e which are the mold main body, and burrs are generated. In severe cases, the lens mirror piece 11a,
This is because the deformation of 12a occurs.

On the other hand, the cavity unit 10 is provided with a self-holding mechanism 15 so that a predetermined mold clamping force can be held by the self-holding mechanism 15. Specifically, as shown in FIGS. 2 and 3, the self-holding mechanism 15 includes a plurality (four) of self-holding bolts 16 that connect the upper and lower dies 11 and 12 of the cavity unit 10 by tightening them in the mold-clamping direction. The self-holding bolt 16 is provided near the cavity 10a and penetrates the mold 11 and is screwed to the mold 12. By adopting the self-holding mechanism 15, the gate portion 10b of the cavity unit 10 is moved to the movable valve body 13 after filling / relaxation by the injection molding machine 60.
So that opening the injection molding machine 60 in a state where the gate sealing, it is possible to maintain the predetermined holding pressure state does not depend on the injection molding machine 60 with slow cooling of the cavity unit 10 alone by. 2 and 3, 14a, 14b
Is a positioning pin for relative positioning of the upper and lower dies 11, 12.

The slow cooling station 40 is provided with a cavity unit taken out of the injection molding machine 60 by opening the machine.
10 is provided with an air-based slow cooling device 41 that gradually cools 10 at a cooling rate of 5 ° C./minute or less to a temperature equal to or lower than a heat deformation temperature (solidification temperature). like,
It is composed of a forced exhaust duct 43 installed on the mold transfer section. The mold transfer section 42 constitutes a part of the transfer means 90, and advances at a fixed speed by a set count number or stops for a set stop time. Further, it is set so that the time of one molding cycle = the moving time of the mold conveying unit 42 + the stopping time. The forced exhaust duct 43
It is provided for the purpose of causing an air flow in the interior covered by the cover to cool the mold more quickly, and the air flow of the entire duct can be adjusted by adjusting the air intake volume of the exhaust duct 43 by air volume scale or the like. Further, in order to change the slow cooling rate (cooling rate) of the cavity unit 10, shielding plates 44 are provided at four positions of the apparatus, and the air flow can be adjusted by changing the directions thereof. .

The molded product take-out station 50 uses a well-known nut runner (automatic tightening tool) 51 as shown in FIG. After loosening the plurality of self-holding bolts 16 of the holding mechanism 15, the upper and lower dies 11, 12 are opened by the die opening / closing device 52 shown in FIG. The mold opening / closing device 52 includes a lifting plate 54 attached to a plurality of guide posts 53 (only one is shown) so as to be able to move up and down, a fixed plate 55 fixed below the lifting plate 54, Attached to plate 54, cavity unit 10
(For example, an automatic type using a pneumatic cylinder) and a mold clamp 57 attached to a fixing plate 55.
And a lifting drive source (not shown). Also,
Since the cavity unit 10 does not have an eject mechanism, the molded product is taken out by a so-called pick-up type take-out device (not shown). The cavity unit 10 from which the molded product has been taken out is tightened with the self-holding bolt 16 by the nut runner 51, and the mold is closed and clamped again.

Next, the injection molding apparatus having the above configuration was used.
An embodiment of the injection molding method according to the invention of claim 6 will be described. First, in this embodiment, the cavity unit
Between the upper and lower molds 11 and 12 of 10, for example, the moving valve body 13 is put into the gate forming groove of the lower mold 12, and the self-holding bolt 16 is tightened by the mold opening / closing device 52 of the molded product take-out station 50, The cavity unit 10 is closed and clamped.

After the cavity unit 10 is uniformly heated to a predetermined temperature in the heating station 20, it is conveyed to the filling / relaxation station 30 and set (clamped) in the injection molding machine 60. Receiving the mold clamping force. In addition to the mold clamping, the cavity unit 10 is also clamped by the pressing mechanism 71 in a direction orthogonal to the mold clamping direction. In this state, the cavity in the cavity unit 10 is injected and filled with the molten resin. When the injection is completed, the gate is sealed by the movable valve body 13 which has received the injection resin pressure on the side of the cavity 10b, and the injection molding machine 60 maintains a constant temperature equal to or higher than the glass transition point in the mold-clamped state for a fixed time. Thus, uneven distribution of the pressure and temperature of the resin in the cavity unit 10 is reduced.

Next, the mold of the cavity unit 10 by the injection molding machine 60 is released, and the cavity unit 10 is released by opening the injection molding machine 60 and releasing the clamp of the pressing mechanism 71.
Is taken out of the injection molding machine 60, the cavity unit 10 is sent to the slow cooling station 40 where it is gradually cooled. At this time, the cavity unit 10 that is gradually cooled
Is tightened by the self-holding bolt 16,
Injection molding machine that can hold a predetermined mold clamping force by itself
Even if the holding pressure of 60 is not used, a desired holding pressure state can be obtained.
Therefore, the transfer surface shape formed on the upper and lower molds 11 and 12 of the cavity unit 10 (the surface forming the cavity 10a)
Is transferred with high accuracy, and unnecessary burrs do not occur.

When the cavity unit 10 is gradually cooled, the resin inside the cavity unit 10 is solidified (cooled to the heat deformation temperature), and when the cavity unit 10 is transported to the molded product take-out station 50, the self-holding bolt is held by the nut runner 51.
16 is loosened, and the mold of the cavity unit 10 is opened. Then, the solidified molded product is taken out of the cavity unit 10 by the take-out type take-out device.
Hereinafter, continuous molding is performed with the above series of steps as one cycle.

As described above, in this embodiment, the injection molding machine 60 fills the cavity unit 10 heated above the glass transition point with molten resin, and the moving valve 13 seals the gate of the cavity unit 10. Then, the cavity unit 10 closed and clamped by the self-holding bolt 16 can self-hold a predetermined mold clamping force. Therefore, the cavity unit 10 is conveyed from the filling / relaxation station 30 to the annealing station 40, and is gradually cooled by the pneumatic annealing device 41.
10 can be filled with molten resin by injection molding machine 60
To shorten the molding time per molded product,
Productivity can be improved. Further, in addition to the cavity unit 10, a cavity unit having a different shape of a molded product can be used, and a molding process in which a plurality of types are mixed can be performed. Further, even after the injection molding machine 60 is opened, the resin temperature and the resin pressure in the cavity unit 10 are appropriately maintained, so that a plastic lens with stable quality and high molding accuracy can be obtained.

Further, since the heating station 20 has a plurality of heating stages having appropriately set temperatures, the heating time can be shortened and uniform heating can be performed, and it is not necessary to provide a temperature adjusting means or the like in the cavity unit. . Further, mold positioning jigs 65 and 66 are provided on the die plate 62 of the injection molding machine 60, and the die plates 61 and 62 have heaters for keeping heat.
Since the 63 and 64 are provided, the temperature can be quickly and uniformly increased in combination with the uniform heating, and the cavity unit 10 can be reduced in size to a small size and low cost which does not require a temperature control means (for example, a hot water passage). In addition, the accuracy of nozzle touch and mold clamping is improved, and mold clamping can be performed at a constant mold temperature. Further, since the pressing mechanism 71 applies a pressing force to the cavity unit 10 in a direction orthogonal to the mold clamping direction, the lens mirror pieces 11a and 12a of the cavity unit 10 and the mold plate portions 11d and 11
The high-pressure resin is prevented from entering between e, 12d, and 12e, and deformation of the lens mirror pieces 11a, 12a is also prevented. Further, the lens mirror pieces 11a, 12a and the template portions 11d, 11e, 12
Since the groove-shaped concave portions were formed at the contact portions with d and 12e,
Although the molded product has a rib shape outside the lens region, the resin is easily cooled and solidified by that amount, and the pressure loss increases. Therefore, generation of burrs is prevented.

Further, since the self-holding mechanism 15 and the movable valve body 13 can ensure an effective pressure-holding state with little variation without depending on the pressure-holding of the injection molding machine 60,
The sealing is assured, and the movable valve body 13 as the gate sealing means can be handled integrally with the mold 11, thereby facilitating the operation. Further, since the self-holding bolt 16 is disposed near the lens mirror pieces 11a and 12a, an effective mold clamping force can be obtained even after the injection molding machine 60 is opened. Furthermore, when the cavity unit 10 is gradually cooled, 5 ° C.
At a cooling rate of less than / minute and below the heat deformation temperature (solidification temperature)
Since the cooling is carried out, uneven cooling is prevented, and a high-quality molded product without deformation such as sink marks can be obtained.

In addition, in the present embodiment, when forming the cavity 10a of the cavity unit 10, a so-called draft angle is not provided, and a taper process for that purpose need not be performed. Therefore, the manufacture of the mold is facilitated and the cost is reduced. In the present embodiment uses the ball as a moving valve body constituting the gate sealing means, the necessary gate seal
It is needless to say that various conventional valve elements can be applied as long as the stop function can be exerted. For example, a polygonal valve element may be used.

[0033]

According to the first aspect of the present invention, the gate sealing is achieved.
While the cavity unit is gradually cooled in the stopped state, the other cavity units can be filled with the molten resin, thereby improving the productivity and maintaining the predetermined space by the self-holding mechanism and the gate sealing means. By maintaining the pressure state, appropriate resin temperature and pressure can be maintained, and molding accuracy can be improved.

Further, according to the second aspect of the present invention, it is possible to perform rapid and uniform heating, it can be as simple a plurality of cavity unit at a low cost without temperature adjusting member, an injection The manufacturing cost of the molding device can be reduced. According to the third aspect of the invention, the pressing force in the direction orthogonal to the mold clamping direction is applied to the cavity unit 10.
Can be prevented, and high-pressure resin can be prevented from entering between the mold piece portion and the mold plate portion of the cavity unit, and also the deformation of the transfer surface shape can be prevented.

According to the invention described in claim 4, the cavity is provided.
Spherical moving valve body receiving resin pressure on the side
Since the gate can be sealed, it is possible to secure the effective predetermined pressure-holding state independent of the injection molding machine. According to the fifth aspect of the present invention, since the self-holding mechanism is disposed near the mold piece, an effective mold clamping force can be obtained even after the injection molding machine is opened. Claim 6
According to the invention described above, since the cavity unit is gradually cooled to a temperature equal to or lower than the thermal deformation temperature at a cooling rate of 5 ° C./min or less, uneven cooling is prevented, and a high-quality molded product without deformation such as sink marks is obtained. be able to.

[Brief description of the drawings]

FIG. 1 is a plan view showing a system configuration of an embodiment of an injection molding apparatus according to the present invention.

FIGS. 2A and 2B are diagrams showing a configuration of a cavity unit according to an embodiment, wherein FIG. 2A is a front sectional view and FIG. 2B is a side sectional view.

FIG. 3 is a perspective view of an upper mold of the cavity unit.

FIG. 4 is a perspective view showing the shape of the cavity.

FIG. 5 is a partial sectional view of a mold heating device according to one embodiment.

FIG. 6 is a side view of the mold heating device.

FIG. 7 is a graph showing a relationship between a mold clamping pressure and a temperature rising time.

FIG. 8 is a diagram showing a configuration of a gate sealing unit according to one embodiment;
(A) shows the injection filling time when the moving valve body moves to the cavity side, and (b) shows the gate sealing time when the moving valve body moves to the nozzle side.

FIG. 9 is a configuration diagram of a vertical injection molding machine of one embodiment.

FIG. 10 is a schematic configuration diagram of a pneumatic slow cooling device of one embodiment.

FIG. 11 is a configuration diagram of a mold opening / closing device for removing a molded product according to one embodiment.

FIG. 12 is an explanatory view of a conventional injection molding method .

FIG. 13 is a graph showing changes in pressure and temperature in each step of the conventional injection molding.

[Explanation of symbols]

10 Cavity unit 10a Cavity 10b Gate section 11, 12 Upper and lower molds 11a, 12a Lens mirror pieces (mold pieces) 11d, 11e, 12d, 12e Mold plate section 13 Moving valve body (gate sealing means) 15 Self-holding mechanism 16 Self-holding bolt 20 Heating station 21 Type heating device (heating means) 30 Filling / relaxation station 40 Slow cooling station 41 Pneumatic slow cooling device (cooling means) 50 Mold removal station 60 Injection molding machine (injection filling means) 61 , 62 Die plate 63, 64 Heat retention heater 65, 66 Mold positioning jig 71 Pressing mechanism (pressing means) 90 Transporting means

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Akira Fukushima 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (72) Inventor Wataru Otani 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (72) Inventor Toshihiro Kanematsu 1-3-6 Nakamagome, Ota-ku, Tokyo Co., Ltd. Inside Ricoh Co., Ltd. (72) Shinya Senoo 1-3-6 Nakamagome, Ota-ku, Tokyo Co., Ltd. Ricoh Company (72) Inventor Jun Watanabe 1-3-6 Nakamagome, Ota-ku, Tokyo Co., Ltd. Ricoh Company (72) Inventor Akishi Hirano 1-3-6 Nakamagome, Ota-ku, Tokyo Co., Ltd. In Ricoh (56) References JP-A-1-139231 (JP, A) JP-A-64-36421 (JP, A) JP-A-51-79160 (JP, A) "Injection mold" (Nikkan Kogyo) Newspaper, 1976 10 days Fourth Edition issue), pp. 157-188 (58) investigated the field (Int.Cl. ^7, DB name) B29C 45/26 - 45/44 B29C 45/73

Claims (7)

(57) [Claims] A plurality of cavity units each comprising a pair of molds each having a cavity formed therein and a self-holding mechanism for self-holding a force in a mold clamping direction by connecting the pair of molds; Conveying means for conveying the cavity unit in the order of a predetermined heating station, filling / relaxation station, slow cooling station, and molded article removal station; heating means provided at the heating station for heating the cavity unit to a temperature equal to or higher than the glass transition point; Injection filling means provided at the relaxation station for injecting and filling the molten resin into the cavity unit heated by the heating means through its gate portion, and moving under the pressure of the resin into each cavity unit.
A gate sealing means having a moving valve body provided; a cooling means provided at the slow cooling station for gradually cooling the cavity unit; and a molded product provided at the molded product take-out station and solidified in the cavity unit. and a demold means for withdrawing from the mold clamping force is held by the self-holding mechanism Cavity
Molten resin is injected into the unit by the injection filling means
When filled, before receiving the resin pressure on the cavity side
The gate of the cavity unit is moved by the moving valve body.
An injection molding device characterized by being sealed . 2. The injection filling means comprises an injection molding machine.
The injection molding apparatus according to claim 1, wherein a mold positioning jig is provided on a die plate of the injection molding machine, and a heater for keeping heat is provided. 3. A pressing means for applying a pressing force in a direction orthogonal to a mold clamping direction is provided in the cavity unit located at the filling / relaxation station.
Or the injection molding apparatus according to 2. 4. The moving valve body of the gate sealing means is provided with a key.
Can be moved to the mold groove of the cavity unit mold
2. A spherical valve body provided.
The injection molding apparatus according to the above. 5. The injection molding apparatus according to claim 1, wherein a groove is provided at a contact portion between a mold piece and a mold plate of a mold constituting the cavity unit. 6. The self-holding mechanism according to claim 1, wherein each of the cavity units has the self-holding mechanism disposed near a mold piece having a transfer surface of a mold constituting the cavity unit. Injection molding equipment. 7. An injection molding method using the injection molding apparatus according to claim 1, wherein when the cavity unit is gradually cooled in the slow cooling station, the cavity unit is cooled at a cooling rate of 5 ° C./min or less. An injection molding method comprising cooling a resin in a cavity unit to a temperature equal to or lower than a heat deformation temperature.