JP2014177047A - Injection molding apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an injection molding apparatus having such a configuration that a metal mold set comprising a plurality of molds is fastened by one fastening unit and to provide a technique for miniaturizing the injection molding apparatus.SOLUTION: The injection molding apparatus comprises: a fastening unit 20; a first fixed quantity measuring/supplying unit 60 attached to a fixed plate 21; and a second fixed quantity measuring/supplying unit 60B attached to a movable plate 60B. As a result, since the first or second fixed quantity measuring/supplying unit has a mechanism for measuring/extruding a fixed amount of a liquefied resin material, the unit becomes smaller and lightweight easily and can be disposed without restraint. In other words, the first or second fixed quantity measuring/supplying unit can be miniaturized satisfactorily when compared with the conventional injection machine comprising a heating cylinder, a screw, a screw rotating mechanism and a screw advancing mechanism. Furthermore, since the first or second fixed quantity measuring/supplying unit can be disposed without restraint, the unit can be attached without widening the width of the injection molding apparatus.

Description

  The present invention relates to an injection molding apparatus in which a mold set composed of a plurality of molds is clamped with a single mold clamping device.

In the field of resin injection molding, it is possible to obtain a resin molded product by nozzle-touching an injection machine to a mold clamped by a mold clamping device and injecting a resin material from the injection machine into a cavity in the mold. It is actively done.
Basically, one set of molds is clamped with one clamping device and injected with one injection machine.

  However, while the equipment is required to be used effectively, for example, a technique for clamping two sets of molds with a single clamping device is proposed (for example, Patent Document 1 (FIG. 5)).

Patent document 1 is demonstrated based on the following figure.
FIG. 11 is a diagram for explaining the basic configuration of a conventional injection molding apparatus, and the first mold 201 and the second mold 202 are clamped by the mold clamping apparatus 200. The mold clamping is performed by attaching a mold clamping cylinder 205 to a pressure receiving plate 204 disposed opposite to the fixed plate 203 and pushing the movable plate 206 with the mold clamping cylinder 205. A first injection machine 207 is disposed on the side opposite to the mold clamping cylinder 205, and a resin material is injected into the first mold 201 by the first injection machine 207. The second mold 202 is injected by the second injection machine 208.

  Since the mold clamping cylinder 205 is arranged on the opposite side of the first injection machine 207, the second injection machine 208 is arranged perpendicular to the axis of the first injection machine 207. Inevitably, the width of the injection molding apparatus increases and the installation floor area increases as the second injection machine 208 extends.

In recent years, a liquid resin material typified by silicone rubber (hereinafter referred to as a liquid resin material) has been molded with a mold.
Even when the liquid resin material is injected by the second injection machine 208, the size of the injection molding apparatus is increased by the extent that the second injection machine 208 extends.

When the injection molding apparatus is enlarged, the number of injection molding apparatuses that can be installed in a factory building is limited. However, from the viewpoint of improving productivity, it is desirable to install as many injection molding apparatuses as possible in the factory building.
In recent years, since improvement in productivity is required, even an injection molding apparatus that molds a mold set composed of a plurality of molds with a single mold clamping device is required to be downsized.

Japanese Patent No. 311624

  An object of the present invention is to provide a technique capable of downsizing even an injection molding apparatus in which a mold set including a plurality of molds is clamped by a single mold clamping device.

  The present inventors have found that if the resin material is limited to a liquid resin material, the structure of the first and second injection machines can be reviewed to suppress an increase in the width dimension of the injection molding apparatus. . And from this knowledge, it came to complete invention.

That is, the invention according to claim 1 is an injection molding apparatus for obtaining a resin molded product by injecting a liquid resin material into a cavity in a mold and solidifying in the mold.
A mold set having a first cavity and a second cavity;
A mold clamping device for clamping the mold set;
A first quantitative metering supply mechanism provided separately from the mold set and metering and extruding the first liquid resin material;
A first supply path extending from the first fixed supply mechanism to the mold set and supplying the first liquid resin material to the first cavity;
A second quantitative metering supply mechanism provided separately from the mold set and metering and extruding the second liquid resin material;
And a second supply path that extends from the second fixed supply mechanism to the mold set and supplies the second liquid resin material to the second cavity.

  In the invention according to claim 2, the first quantitative metering supply mechanism is mounted on the stationary platen of the mold clamping device via the first bracket, and the second quantitative metering supply mechanism is provided on the mold clamping device via the second bracket. It is mounted on a movable board.

In the invention according to claim 3, if the supply pressure of the first liquid resin material is not more than a predetermined value in the middle of the first supply path or between the first supply path and the first cavity, the first supply path is closed. A first nozzle opening / closing mechanism that opens when the supply pressure of the liquid resin material exceeds a predetermined value;
If the supply pressure of the second liquid resin material is less than or equal to a predetermined value in the middle of the second supply path or between the second supply path and the second cavity, the supply pressure of the second liquid resin material is predetermined. A second nozzle opening / closing mechanism that opens when the value is exceeded is provided.

  The invention according to claim 4 further includes an injection machine that injects a non-liquid resin material into the first cavity.

The invention according to claim 5 is an injection molding apparatus for obtaining a resin molded product by injecting a liquid resin material into a cavity in a mold and solidifying in the mold.
A mold set having a cavity;
A mold clamping device for clamping the mold set;
A first quantitative metering and feeding mechanism that is provided separately from the mold set and quantitatively measures and extrudes the first liquid resin material, or a second liquid resin material that is provided separately from the mold set and extrudes and extrudes. A second quantitative metering supply mechanism;
A first supply path that extends from the first quantitative supply mechanism to the mold set and supplies the first liquid resin material to the cavity, or extends from the second quantitative supply mechanism to the mold set and extends to the mold set. A second supply path for supplying a second liquid resin material to the cavity;
An injection machine for injecting a non-liquid resin material into the cavity;
It is characterized by comprising.

In the invention according to claim 1, the constituent elements corresponding to the conventional injection machine are constituted by the first and second quantitative metering supply mechanisms and the first and second supply paths. The quantitative metering supply mechanism is a mechanism that measures and extrudes a certain amount of the liquid resin material, so that it is easy to reduce the size and weight, and can be freely arranged.
That is, the quantitative metering supply mechanism of the present invention can be sufficiently downsized compared to a conventional injection machine including a heating cylinder, a screw, a screw rotation mechanism, and a screw advance mechanism. In addition, since the arrangement is free, it is possible to attach the quantitative metering supply mechanism without increasing the width of the injection molding apparatus.

In the invention according to claim 2, the first and second quantitative metering supply mechanisms are respectively mounted on the fixed plate and the movable plate of the mold clamping device. The relative position between the mold set and the stationary platen and the relative position between the mold set and the movable platen do not change. Therefore, the first and second supply passages connecting the first and second quantitative metering supply mechanisms and the mold set are not repeatedly bent or even slightly applied.
As a result, the service life of the first and second supply paths can be extended, and the parts replacement cost can be saved.

In the invention according to claim 3, the first and second nozzle opening / closing mechanisms are provided in the middle of the first and second supply paths or between the first and second supply paths and the first and second cavities. Yes.
Since the nozzle opening / closing mechanism is provided, leakage can be suppressed even with a liquid resin material having high fluidity.

  In the invention according to claim 4, the first liquid resin material is injected into the first cavity by the first constant metering and supply mechanism, and the resin material (for example, thermoplastic resin material) harder than the liquid resin material is injected by the injection machine. Can be selectively implemented. Therefore, two resin molded products having different forms and resin materials can be obtained.

In the invention which concerns on Claim 5, a non-liquid resin material is inject | poured into the metal mold | die set clamped with the injection machine, and a liquid resin material is inject | poured with a 1st fixed quantity supply mechanism or a 2nd fixed quantity supply mechanism.
That is, an apparatus is completed only by attaching a first quantitative metering supply mechanism or a second quantitative metering supply mechanism to an existing injection molding apparatus composed of an injection machine and a mold clamping device. Since the completed injection molding apparatus can handle non-liquid resin materials and liquid resin materials, the use is dramatically expanded.
Since the attached first quantitative metering supply mechanism or second quantitative metering supply mechanism is sufficiently small, it is possible to suppress an increase in the size of the injection molding apparatus.

It is a side view of the injection molding device concerning the present invention. It is a principle diagram of the first and second pump mechanisms. It is a principle diagram of the first and second quantitative metering supply mechanisms. It is a principle diagram of the first and second injection nozzles. It is an operation view of the first and second injection nozzles. It is a side view which shows the example of a change of an injection molding apparatus. It is a principle diagram of the first and second nozzle opening and closing mechanism. It is a side view which shows the further example of a change of an injection molding apparatus. It is a side view which shows the further example of a change of an injection molding apparatus. It is a side view which shows the further example of a change of an injection molding apparatus. It is a figure explaining the basic composition of the conventional injection molding device.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings are viewed in the direction of the reference numerals.

  As shown in FIG. 1, an injection molding apparatus 10 includes a machine base 11, a mold clamping device 20 mounted on the machine base 11, a mold set 30 clamped by the mold clamping apparatus 20, and the mold. First and second quantitative metering supply mechanisms 60, 60B provided separately from the set 30, and first and second supply channels extending from the first and second quantitative metering supply mechanisms 60, 60B to the mold set 30 39 and 39B are main components. Details of the components will be described in detail below.

  The mold clamping device 20 includes a fixed plate 21 fixed to the machine base 11, a pressure receiving plate 22 fixed to the machine base 11 at a position away from the fixed plate 21, and the pressure receiving plate 22. A movable plate 23 disposed between the platen 21, tie bars 24, 24 that are passed to the pressure platen 22 and the fixed platen 21 to guide the movable platen 23, and a mold that is attached to the pressure platen 22 and pushes out the movable platen 23 And a fastening cylinder 25. The mold clamping cylinder 25 may be a toggle mechanism.

The mold set 30 includes a first mold 31 attached to the fixed platen 21, a second mold 32 attached to the movable platen 23, and a third mold 33 sandwiched between the first mold 31 and the second mold 32.
In this example, a first sprue 34 is provided between the first mold 31 and the third mold 33, and a second sprue 35 is provided between the second mold 32 and the third mold 33.
Then, the first liquid resin material 51 is injected into the first cavity 36 via the first sprue 34, and the second liquid resin material 51 </ b> B is injected into the second cavity 37 via the second sprue 35.

Although the detailed structure of the first quantitative metering supply mechanism 60 will be described later, the first quantitative metering supply mechanism 60 is attached to the stationary platen 21 via the first bracket 41. A vertical rail 42 is attached to the first bracket 41, and a slider 43 is attached to the vertical rail 42 so as to be movable up and down. A first injection nozzle 100 (detailed structure will be described later) is attached to the slider 43. The first injection nozzle 100 is moved up and down by a first cylinder 44 lowered from the first bracket 41, and makes a nozzle touch on the first sprue 34 when lowered.
The first liquid resin material 51 is supplied to the first quantitative metering supply mechanism 60 by the first pump mechanism 50.

  As shown in FIG. 2, the first pump mechanism 50 includes a container 52 in which a first liquid resin material 51 in which an additive such as a curing agent is added and sufficiently mixed is added to the main agent, and in this container 52. A drop lid-shaped disk 53 to be set, a suction pipe 54 standing from the center of the disk 53, a pump casing 55 connected to the upper end of the suction pipe 54, and an upper surface of the pump casing 55 are fixed. A pump motor 56 that rotates pump blades built in the pump casing 55 at high speed, a discharge port 57 that extends laterally from the pump casing 55, and a discharge pipe 58 that extends from the discharge port 57.

  The disc 53 is provided with a sealing material 59 such as an O-ring, and the disc 53 is tightly fitted to the inner peripheral surface of the container 52. Then, the pump motor 56 is started. The first liquid resin material 51 is discharged from the discharge port 57. With this discharge, the upper surface of the first liquid resin material 51 is lowered, but the disk 53 is also lowered together. Will not be mixed.

  The second pump mechanism 50B is a mechanism having the same configuration as the first pump mechanism 50 except that the second liquid resin material 51B is sucked and discharged, and detailed description thereof is omitted.

  In FIG. 1, the first liquid resin material 51 that is pumped by the first pump mechanism 50 is sent to the first fixed metering and feeding mechanism 60 via the discharge pipe 58, and is pumped by the second pump mechanism 50 </ b> B. The second liquid resin material 51B is sent to the second quantitative metering supply mechanism 60B through the discharge pipe 58B.

  As shown in FIG. 3, the first quantitative metering supply mechanism 60 discharges the liquid resin material from the pot portion 62 for storing the liquid resin material, the inlet 63 for introducing the liquid resin material into the pot portion 62, and the pot portion 62. A main body portion 65 having an outlet 64, a plunger 66 movably attached to the main body portion 65 and retreating (rising up in the drawing) by the pressure of the liquid resin material accumulated in the pot portion 62, and a plunger provided in the main body portion 65 A plunger pushing means 67 for pushing 66 forward, an inflow valve 68 provided in the discharge pipe 58 for blocking or allowing the flow of the liquid resin material, and a flow of the liquid resin material provided in the first supply path 39 for blocking or And an allowed outflow valve 69.

  The plunger push-out means 67 includes a bracket 71 provided on the upper portion of the main body 65, a plurality of rods 72 standing from the bracket 71, a top plate 73 fixed to the upper ends of these rods 72, and the top plate 73. Are provided on the top plate 73, a nut 74 that is guided below the rod 72 so as to be movable up and down, a piston rod 75 that is integrally formed with the nut 74, a feed screw 76 that is screwed into the nut 74 and extends upward. A thrust bearing 77 that rotatably supports the feed screw 76, a driven pulley 78 provided at the upper end of the feed screw 76, a servo motor 79 provided on the top plate 73, and a drive attached to the motor shaft 81 of the servo motor 79. A pulley 82 and a bell connecting the drive pulley 82 and the driven pulley 78 83, and a control unit 84 which controls the servo motor 79.

  Furthermore, a pressure gauge 85 that measures the pressure of the liquid resin material in the vicinity of the outlet 64 is attached to the main body 65. A storage case 86 is fixed to the upper end of the plunger 66, and a proximity sensor 87 is stored in the storage case 86. The proximity sensor 87 detects the contact state between the piston rod 75 and the storage case 86.

The inflow port 63 is provided at a position offset by a distance L from the outflow port 64 toward the plunger pusher 67 in the axial direction of the plunger 66.
Furthermore, the plunger 66 is provided with a material flow path 91 that guides the liquid resin material supplied from the inlet 63 to the tip of the plunger 66 even when the plunger 66 is at the most advanced position.
The material flow path 91 is preferably a spiral groove 92 provided in a spiral shape on the outer peripheral surface of the plunger 66.
Since it is the spiral groove 92, there is no fear that force in the direction perpendicular to the axis is applied to the plunger 66, and the sliding resistance between the plunger 66 and the main body 65 can be lowered.
Further, since the spiral groove 92 is used, the flow resistance is larger than that of the straight groove, and the back flow of the liquid resin material can be prevented.

The operation of the first quantitative metering supply mechanism 60 having such a configuration will be described next.
The piston rod 75 stands by at a predetermined position, that is, a preset measurement completion position. When the plunger 66 is pushed up by the liquid resin material and the storage case 86 and the piston rod 75 come into contact with each other, this contact is detected by the proximity sensor 87 and it is detected that the plunger 66 has reached a predetermined position. When there is a concern about erroneous detection of the proximity sensor 87, erroneous detection may be prevented by using both detection by the proximity sensor 87 and completion of timing for a predetermined time, or the proximity sensor 87 may be used instead. Thus, highly accurate position detecting means may be employed. It is determined that measurement has been completed based on the detection.

  The inflow valve 68 is closed and the outflow valve 69 is opened. The piston rod 75 is lowered by causing the servo motor 79 to output at a first torque that is a predetermined torque. Then, the plunger 66 moves forward, and the liquid resin material is supplied to the first cavity via the first supply path 39. During this supply, the pressure of the liquid resin material is measured by the pressure gauge 85 and sent to the control unit 84.

  When the pressure of the liquid resin material reaches a predetermined pressure, the control unit 84 controls the servo motor 79 by changing it to a second torque lower than the first torque. This control is called holding pressure control. When the plunger 66 moves forward to the forward limit or the supply time reaches a predetermined time, the material discharge is completed.

  The second quantitative metering supply mechanism 60B is the same as the first metering metering supply mechanism 60 except that the second liquid resin material is received by the discharge pipe 58B and led to the second supply path 39B. Description is omitted.

  As shown in FIG. 4, the first injection nozzle 100 includes a cylinder 103 having a nozzle hole 101 at the tip and an introduction hole 102 on a side surface, a piston 104 movably fitted in the cylinder 103, and the piston A plug portion 105 that extends from 104 and closes the nozzle hole 101, a spring 106 that pushes the back surface of the piston 104, and a lid 107 that closes the opening of the cylindrical body 103.

  As shown in FIG. 5, when a high-pressure liquid resin material exceeding a predetermined value is introduced into the cylindrical body 103 from the introduction hole 102, the spring 106 is compressed by the resin pressure, and the piston 104 moves backward. As a result, the plug portion 105 is separated from the nozzle hole 101, and the liquid resin material is discharged from the nozzle hole 101.

That is, the first injection nozzle 100 includes a first nozzle opening / closing mechanism 108 that is closed when the supply pressure of the liquid resin material is a predetermined value or less and opens when the supply pressure of the liquid resin material exceeds the predetermined value. . The first nozzle opening / closing mechanism 108 includes a plug portion 105, a piston 104, and a spring 106.
The predetermined value corresponds to the injection pressure (discharge pressure) required from the moldability.
The nozzle opening / closing mechanism may be a cylinder opening / closing mechanism, but a spring opening / closing mechanism is preferable in that it contributes to downsizing of the apparatus.

  Since the second injection nozzle 100B is the same as the first injection nozzle 100 except that the second injection nozzle 100B is opened and closed by the second nozzle opening and closing mechanism 108B, detailed description of the structure is omitted.

  In FIG. 1, an appropriate amount of the first liquid resin material 51 is injected into the first cavity 36, and an appropriate amount of the second liquid resin material 51 </ b> B is injected into the second cavity 37. The resin molded product can be obtained. For this purpose, the first and second quantitative metering and feeding mechanisms 60 and 60B are much smaller than conventional injection machines (consisting of a heating cylinder, a screw, a screw rotating mechanism, and a screw advancing mechanism). Therefore, the injection molding apparatus 10 is sufficiently compact.

  Moreover, the flexible tube represented by the flexible hose is suitable for the 1st and 2nd supply paths 39 and 39B. This is because flexibility increases the degree of freedom of arrangement of the first and second quantitative metering supply mechanisms 60 and 60B.

Next, a modified example of the present invention will be described based on the drawings.
As shown in FIG. 6, with respect to FIG. 1, the injection molding apparatus 10 </ b> B incorporates a first nozzle opening / closing mechanism 108 in a first mold 31, and a joint 111 is screwed into the first mold 31. The point that the tip of the supply passage 39 is connected, the second nozzle opening / closing mechanism 108B is built in the second die 32, the joint 111B is screwed into the second die 32, and the tip of the second supply passage 39B is connected to the joint 111B. Different. Since others are the same as FIG. 1, detailed description is abbreviate | omitted using a code | symbol.

  In FIG. 6, the first and second brackets 41 and 41B are smaller than those in FIG. 1, and the first and second brackets 41 and 41B are made clearer. Therefore, the injection molding apparatus 10B is further downsized. Is possible.

  As shown in FIG. 7, the first nozzle opening / closing mechanisms 108 and 108B built in the first and second molds 31 and 32 are movably fitted in the introduction hole 102 and the first and second molds 31 and 32, respectively. The piston 104 includes a plug portion 105 that extends from the piston 104 and closes the nozzle hole 101, a spring 106 that pushes the back surface of the piston 104, and a lid 107 that closes the opening of the cylinder 103. Since the operation is the same as in FIG.

An injection molding apparatus 10C shown in FIG. 8 has a structural feature in that an injection machine 112 is added to FIG. In other cases, reference numerals are used to omit the description of the structure.
In the injection molding apparatus 10 </ b> C, the first liquid resin material 51 is injected into the first cavity 36 by the first quantitative metering supply mechanism 60, and the resin material harder than the liquid resin material by the injection machine 112 (for example, a thermoplastic resin material). Can be selectively performed. Therefore, two resin molded products having different forms and resin materials can be obtained. In addition, by injecting the resin material into the second cavity by the injection machine, it becomes possible to take a large number of composite molded products without complicating the mold structure.

In other words, the existing injection molding apparatus composed of the injection machine 112 and the mold clamping device 20 includes first and second pump mechanisms 50 and 50B, first and second quantitative metering supply mechanisms 60 and 60B, It can be said that the injection molding apparatus 10C is completed only by adding the second supply paths 39 and 39B.
By simply remodeling an existing injection molding apparatus, the convenience of the injection molding apparatus 10C is greatly improved.

  Further, an injection molding apparatus 10D as shown in FIG. 9 can be easily obtained. In the injection molding apparatus 10D, a molded product made of a resin material harder than the liquid material is obtained in the first cavity 36, and a soft molded product made of the liquid material is obtained simultaneously in the second cavity 37.

  Furthermore, an injection molding apparatus 10E shown in FIG. 10 can be easily obtained. In this injection molding apparatus 10E, in the first cavity 36, a molded product made of a resin material harder than the liquid material or a soft molded product made of the liquid material is selectively obtained. It is also easy to obtain a composite molded product.

  In the present invention, one or two cavities are provided in the mold set, but the number of cavities may be three or more.

  The present invention is suitable for an injection molding apparatus that handles a liquid resin material.

  10, 10B, 10C, 10D, 10E ... Injection molding device, 20 ... Clamping device, 21 ... Fixed platen, 23 ... Movable platen, 30 ... Mold set, 36 ... First cavity, 37 ... Second cavity, 39 ... 1st supply path, 39B ... 2nd supply path, 41 ... 1st bracket, 41B ... 2nd bracket, 51 ... 1st liquid resin material, 51B ... 2nd liquid resin material, 60 ... 1st fixed metering supply mechanism , 60B, second quantitative metering supply mechanism, 108, first nozzle opening / closing mechanism, 108B, second nozzle opening / closing mechanism, 112, injection machine.

Claims (5)

In an injection molding apparatus for obtaining a resin molded product by injecting a liquid resin material into a cavity in a mold and solidifying in the mold,
A mold set having a first cavity and a second cavity;
A mold clamping device for clamping the mold set;
A first quantitative metering supply mechanism provided separately from the mold set and metering and extruding the first liquid resin material;
A first supply path extending from the first fixed supply mechanism to the mold set and supplying the first liquid resin material to the first cavity;
A second quantitative metering supply mechanism provided separately from the mold set and metering and extruding the second liquid resin material;
A second supply path extending from the second constant supply mechanism to the mold set and supplying the second liquid resin material to the second cavity;
An injection molding apparatus comprising: The first quantitative metering supply mechanism is mounted on the fixed plate of the mold clamping device via the first bracket,
2. The injection molding apparatus according to claim 1, wherein the second quantitative metering supply mechanism is mounted on a movable platen of the mold clamping device via a second bracket. If the supply pressure of the first liquid resin material is not more than a predetermined value in the middle of the first supply path or between the first supply path and the first cavity, the first liquid resin material is closed. A first nozzle opening / closing mechanism that opens when the supply pressure exceeds a predetermined value;
If the supply pressure of the second liquid resin material is lower than a predetermined value in the middle of the second supply path or between the second supply path and the second cavity, the second liquid resin material is closed. The injection molding apparatus according to claim 1 or 2, further comprising a second nozzle opening / closing mechanism that opens when the supply pressure exceeds a predetermined value.   The injection molding apparatus according to claim 1, further comprising an injection machine that injects a non-liquid resin material into the first cavity. In an injection molding apparatus for obtaining a resin molded product by injecting a liquid resin material into a cavity in a mold and solidifying in the mold,
A mold set having a cavity;
A mold clamping device for clamping the mold set;
A first quantitative metering and feeding mechanism that is provided separately from the mold set and quantitatively measures and extrudes the first liquid resin material, or a second liquid resin material that is provided separately from the mold set and extrudes and extrudes. A second quantitative metering supply mechanism;
A first supply path that extends from the first quantitative supply mechanism to the mold set and supplies the first liquid resin material to the cavity, or extends from the second quantitative supply mechanism to the mold set and extends to the mold set. A second supply path for supplying a second liquid resin material to the cavity;
An injection machine for injecting a non-liquid resin material into the cavity;
An injection molding apparatus comprising:

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