JP6069470B1 - Injection device, injection molding machine and injection method - Google Patents

Abstract

An object of the present invention is to add to a thermoplastic resin while minimizing shearing and cutting of continuous reinforcing fibers. SOLUTION: A barrel 20 and a screw 30 accommodated in the barrel 20 are provided. The screw 30 has a first material melting portion 50 to which a thermoplastic resin is supplied and a second material to which a continuous reinforcing fiber is supplied. The second material kneading unit 60 includes a second supply unit 61, a second compression unit 62, and a second metering unit 63, and the barrel 30 includes the second supply unit 61. And the fiber supply part 23 which sends a reinforced fiber in the position spaced apart from the boundary with the 1st material fusion | melting part 50 at least more than the distance equal to 1 pitch of the flight 32 of the screw 30 is provided. [Selection] Figure 1

Description

The present invention, I De apparatus, a injection molding machine及beauty injection how, to a technique for adding reinforcing fibers while particular melt the thermoplastic resin.

  Conventionally, in order to improve the strength of a molded product, reinforcing fibers such as carbon fiber and glass fiber are added to a thermoplastic resin to produce a molded product of fiber reinforced resin. As a method for producing a molded product of fiber reinforced resin, a method is known in which pellets in which reinforced fibers are added to a thermoplastic resin in advance are supplied to an apparatus, and melted and kneaded for molding. Also known is a method in which thermoplastic resin pellets are supplied to the apparatus and melted, and continuous reinforcing fibers are supplied from the middle, and the reinforcing fibers are sheared and cut and kneaded with the molten thermoplastic resin to form. It has been.

  Such molding methods include in-line injection molding machines that continuously perform the process from melting of the pellets to injection into the mold, and melting the pellets with a plasticizer, adding reinforcing fibers, and supplying them to the plunger device. This is performed using a plunger-type injection molding machine that injects into a mold (see, for example, Patent Document 1).

JP 2009-242616 A

  However, the above-described injection molding machine has the following problems.

  In an inline type injection molding machine, pellets in which reinforcing fibers have been added to thermoplastic resin in advance are supplied and molded, so the length of reinforcing fibers contained in the pellets is not sufficient, and a molded product with a desired strength can be obtained. In some cases, the reinforcing fibers are sheared and cut in the process of kneading with a screw and shortened, and a molded product having a desired strength may not be obtained.

  Even in the plunger type injection molding machine, if the reinforcing fiber supplied in the middle is finely sheared and cut by a plasticizer and a molded product with a desired strength cannot be obtained, or the reinforcing fiber supplied from the middle is excessive. There is a case where a molded product having a desired strength cannot be obtained due to insufficient addition to the thermoplastic resin wound around the screw and melted.

Accordingly, the present invention performs kneading with a molten thermoplastic resin while maintaining a length capable of exhibiting sufficient strength while minimizing shearing and cutting of continuously supplied reinforcing fibers, device out morphism Ru can be added reinforcing fibers in thermoplastic resins, and its object is to provide an injection molding machine及beauty injection how.

To achieve the solution to the purpose of the problem, it De apparatus of the present invention, an injection molding machine及beauty injection how is constructed as follows.

And barrel, housed within the barrel, the flight is provided in a spiral manner around the circumference of the shaft, and a plasticizing unit having a screw which is rotated by the drive movement unit, and the cylinder, the inner cylinder by the driving unit An injection device comprising a plunger device having a plunger that moves forward or backward, and a pipe that connects the barrel and the cylinder, wherein the screw is thermoplastic from the proximal side to the distal side . A first material melting portion to which resin is supplied and a second material kneading portion to which continuous reinforcing fibers in the form of threads or belts are supplied , the first material melting portion from the proximal end side to the distal end side The first supply part, the first compression part, and the first metering part are provided, and the shaft body has a diameter D1 in the first supply part, and a gradual diameter in the first compression part. Larger than the diameter D1 in the first measuring section. Heard diameter D2, and the prior SL second material kneading section, toward the proximal end side to the distal side, and a second feed portion, a second compression unit, and a second metering section has a said shaft body , in the second supply part is to the diameter D2 smaller than the diameter D3, the gradual diameter becomes large in the second compression unit, and in the second measuring section and the diameter D3 is greater than the diameter D4, and the prior SL barrel, the A fiber supply unit that feeds the reinforcing fibers to a position that is a second supply unit and is separated from the boundary with the first material melting unit by at least a distance equal to one pitch of the screw flight is provided.

A first material melting portion that is housed in a barrel of the plasticizing apparatus and is supplied with thermoplastic resin from the base end side toward the tip end side, and a second material kneading portion that is supplied with continuous reinforcing fibers in the form of threads or belts And the first material melting part has a first supply part, a first compression part, and a first metering from the base end side toward the tip end side. and parts, and having a, in screw second material kneading section before SL is, toward the base end side to the tip side, to be classified and the second supply section, and the second compression unit, and a second measuring unit, The shaft body has a diameter D1 in the first supply section, a gradually increasing diameter in the first compression section, a diameter D2 larger than the diameter D1 in the first metering section, and the diameter in the second supply section. The diameter D3 is smaller than the diameter D2, the diameter gradually increases in the second compression portion, and the second measurement In the in diameter D3 larger diameter D4, by adding the reinforcing fibers by melting the pre Kinetsu thermoplastic resin to produce a fiber-reinforced resin in a molten state, the molten state discharged from the plasticizing unit The fiber-reinforced resin is injected into the cylinder of the plunger device, and the plunger is operated to inject the molten fiber-reinforced resin, wherein the thermoplastic material is used in the first material melting portion of the plasticizing device. Melting the resin and feeding the reinforcing fiber from a position separated from the boundary between the second supply part and the first material melting part by a distance equal to or greater than at least one pitch of the flight of the screw, and the second material kneading part Kneading the thermoplastic resin and the reinforcing fiber melted in the step, and adding the reinforcing fiber to the thermoplastic resin to produce a molten fiber reinforced resin; The fiber-reinforced resin in the molten state the fed into the cylinder of the turbocharger unit, is injected by operating the plunger.

  According to the present invention, kneading with a thermoplastic resin melted in a state in which it is maintained in a length capable of exhibiting sufficient strength while minimizing shearing and cutting of continuously supplied reinforcing fibers, Reinforcing fibers can be added to the thermoplastic resin. Thereby, the molded article of desired intensity | strength can be manufactured.

Sectional drawing which shows the injection molding machine provided with the plasticizing apparatus which concerns on embodiment of this invention. The side view which shows the axial body of the screw integrated in a plasticizing apparatus. Explanatory drawing which shows the flight projection part of a screw from an axial direction. The side view which shows the axial body of the screw as a comparative example. Explanatory drawing which shows the flight projection part of the screw as a comparative example from an axial direction.

  An embodiment of the present invention will be described with reference to FIGS.

  In FIG. 1, the injection molding machine 1 provided with the plasticizing apparatus 10 which concerns on embodiment of this invention is shown. The injection molding machine 1 includes an injection device 2 and a mold clamping device (not shown) for opening and closing the mold 3. The injection device 2 melts a thermoplastic resin that is one of the materials of a molded product, and adds a reinforcing fiber that is also one of the materials to generate a fiber-reinforced resin in a molten state; A plunger device 11 for injecting the produced molten fiber reinforced resin into the cavity 4 of the mold 3 is provided.

  The plasticizing apparatus 10 includes a cylindrical barrel 20 and a screw 30 incorporated in the barrel 20 and arranged coaxially. The screw 30 includes a shaft body 31 and a flight 32 provided in a spiral shape on the outer periphery of the shaft body 31. P in the figure indicates the distance between adjacent flights 32, that is, the flight pitch. The base end of the screw 30 is connected to the drive unit 33. The drive unit 33 includes a motor, a rotating shaft, and the like (not shown). A screw head 34 is attached to the tip of the screw 30. In the drawing, a one-dot chain line C indicates a rotation axis of the screw 30 and the shaft body 31, and the screw 30 is rotationally driven by the drive unit 33.

  The screw 30 has a first material melting part 50 on the base end side that is the upstream side, and a second material kneading part 60 on the tip side that is the downstream side. The first material melting unit 50 and the second material kneading unit 60 are adjacent to each other. That is, in the screw 30, the first material melting part 50 and the second material kneading part 60 are arranged next to the first material melting part 50 from the upstream side proximal end side to the downstream side distal end side. ing. Further, the first material melting unit 50 is divided into a first supply unit 51, a first compression unit 52, and a first metering unit 53 from the proximal end side toward the distal end side. Similarly, the second material kneading unit 60 is also divided into a second supply unit 61, a second compression unit 62, and a second metering unit 63 from the proximal end side toward the distal end side. Therefore, it can be said that the 1st measurement part 53 and the 2nd supply part 61, the 1st material fusion | melting part 50 and the 2nd supply part 61, the 1st measurement part 53, and the 2nd material kneading part 60 are adjacent.

  Here, the shaft body 31 of the screw 30 will be described with reference to FIG. The diameter of the shaft body 31 changes along the rotation axis C direction. In the first material melting unit 50, the shaft body 31 has a constant diameter D1 in the first supply unit 51, a gradually increasing diameter in the first compression unit 52, and a constant larger than the diameter D1 in the first measuring unit 53. Of the diameter D2. Further, in the second material kneading unit 60, the shaft body 31 has a constant diameter D3 smaller than the diameter D2 in the second supply unit 61, and gradually increases in diameter in the second compression unit 62. Then, it becomes a constant diameter D4 larger than the diameter D3. In addition, the passing of the flight 32 formed on the outer periphery of the shaft body 31, that is, the screw diameter of the screw 30 is a constant value from the first material melting part 50 to the second material kneading part 60. The screw diameter of the screw 30 is set slightly smaller than the inner diameter of the barrel 20.

  In the state where the screw 30 described above is incorporated in the barrel 20, the base end side of the barrel 20 is in the same direction as the base end side of the screw 30, and the base end side of the barrel 20 is the upstream side.

  The barrel 20 is a base end side of the barrel 20 and a resin supply unit 21 for supplying the pellet-shaped thermoplastic resin Q to the first supply unit 51 at a position facing the first supply unit 51 of the screw 30. Is provided. The resin supply part 21 is formed with a supply hole 22 penetrating from the outer periphery to the inner periphery of the barrel 20 so that the thermoplastic resin Q can be introduced into the first supply part 51.

  Further, the barrel 20 is an intermediate portion of the barrel 20, and is reinforced fiber such as carbon fiber or glass fiber that is continuous with the second supply unit 61 in a thread-like or belt-like manner at a position facing the second supply unit 61 of the screw 30. A fiber supply unit 23 for supplying F is provided. The fiber supply part 23 is formed with a supply hole 24 penetrating from the outer periphery to the inner periphery of the barrel 20 so that the reinforcing fiber F can be fed into the second supply part 61. The supply hole 24 is a boundary between the first material melting part 50 and the second material kneading part 60 of the screw 30 and from the depressurization position X which is also a boundary between the first measuring part 53 and the second supply part 61. It is provided at a position separated at least by a distance equal to or greater than one pitch (1P) of the flight 32 toward the downstream end side. In other words, the barrel 20 is a reinforcing fiber at a position separated from the boundary with the first material melting unit 50 by at least a distance equal to or more than one pitch (1P) of the flight 32 of the screw 30 from the boundary with the first material melting unit 50. A fiber supply unit 23 for feeding F is provided.

  A pipe 12 connected to the cylinder 40 of the plunger device 11 is provided at the tip of the barrel 20. The plunger device 11 includes a plunger 41 that moves forward and backward in the cylinder 40 by a drive unit (not shown).

  In the injection molding machine 1 including the plasticizing apparatus 10 configured as described above, injection molding is performed as follows.

  That is, the barrel 20 and the cylinder 40 are fixed to each other by a heater (not shown) provided on the outer periphery of the barrel 20 of the plasticizer 10 and a heater (not shown) provided on the outer periphery of the cylinder 40 of the plunger device 11. Heat to temperature. Next, the screw 30 is continuously rotated by the drive unit 33. Next, the thermoplastic resin Q is put into the first supply part 51 of the screw 30 by supplying the pellet-shaped thermoplastic resin Q through the supply hole 22 of the resin supply part 21 provided in the barrel 20. The introduced thermoplastic resin Q is melted and measured while being transferred from the first supply unit 51 of the first material melting unit 50 to the first compression unit 52 and the first measuring unit 53 by the rotation of the screw 30. The melted and weighed thermoplastic resin Q is continuously transferred by the rotation of the screw 30, passes through the depressurization position X, and reaches the second supply unit 61.

  Next, the reinforcing fiber F such as continuous carbon fiber or glass fiber in the form of thread or belt is supplied through the supply hole 24 of the fiber supply unit 23 provided in the barrel 20, thereby supplying the second supply unit 61 of the screw 30. Reinforcement fiber F is fed. At this time, there is a possibility that the reinforcing fiber F is excessively wound around the screw 30, but this is solved by the present invention. The reason will be described later. Note that the volume between adjacent flights 32 in the second supply unit 61 downstream of the depressurization position X is larger than the volume between adjacent flights 32 in the first measuring unit 53 upstream of the depressurization position X. Since it is large, the pressure of the molten thermoplastic resin Q is lowered at the second supply unit 61, and it becomes easy to feed the reinforcing fibers F, and the reinforcing fibers F are not drawn upstream.

  By rotating the screw 30, the reinforcing fiber F continuous with the molten thermoplastic resin Q is transferred from the second supply unit 61 of the second material kneading unit 60 to the second compression unit 62, and the second compression unit 62 uses the reinforcing fiber F. And the melted thermoplastic resin Q and the sheared and cut reinforcing fiber F are kneaded. Reinforcing fibers maintained in a length that can minimize shearing and cutting and exhibit sufficient strength in the molten thermoplastic resin Q by kneading in the second compression unit 62 of the second material kneading unit 60 F is added to produce a fiber reinforced resin in a molten state. The produced molten fiber reinforced resin is continuously transferred to the second measuring unit 63 by the rotation of the screw 30, measured, and discharged from the plasticizing device 10.

  A molten fiber reinforced resin continuously discharged from the plasticizing device 10 is fed into the cylinder 40 of the plunger device 11 through the pipe 12. The plunger 41 is operated, and the fiber reinforced resin in the molten state supplied into the cylinder 40 is injected into the cavity 4 formed inside the mold 3 by performing a mold clamping operation by operating a mold clamping device in advance. Thereafter, the molten fiber reinforced resin injected into the cavity 4 is cooled in the mold 3 to produce a molded product.

  Here, the reason why the phenomenon in which the reinforcing fiber F is excessively wound around the screw 30 is eliminated will be described with reference to FIGS.

  As shown in FIG. 2, in the present invention, the supply hole 24 of the fiber supply unit 23 is spaced from the pressure-reducing position X to the downstream end side by a distance equal to or greater than at least one pitch (1P) of the flight 32. Is provided. For this reason, when the flight 32 is viewed in the direction of the rotation axis C, as shown in FIG. 3, the projection surface of the flight 32 removes the cross section of the shaft body 31 from the passing of the flight 32, that is, from a circle having a screw diameter. It becomes a circular ring. The area of this projection surface is proportional to the thrust for pushing the molten thermoplastic resin Q downstream. For this reason, in order to push the molten thermoplastic resin Q and the fed reinforcing fiber F with a large thrust, the reinforcing fiber F is prevented from being excessively wound around the screw 30 in the region of the two-dot chain line G, and finely sheared or cut. it can. Therefore, it is possible to knead and add to the molten thermoplastic resin Q the reinforcing fiber F maintained in a length that can minimize shearing and cutting and exhibit sufficient strength.

  On the other hand, in FIG. 4, as a comparative example, the shaft 31A of the screw 30A in which the distance from the decompression position X to the supply hole 24 of the fiber supply unit 23 is equal to ¼ of the pitch P of the flight 32A. Indicates. Since the distance from the decompression position X to the supply hole 24 of the fiber supply unit 23 is (1/4) P, as shown in FIG. 5, the projection plane of the flight 32 is 1/4 of the projection plane in FIG. It becomes. Then, the thrust for pushing the molten thermoplastic resin Q and the fed reinforcing fiber F forward is not sufficiently obtained, and the reinforcing fiber F is excessively wound around the screw 30A in the region of the two-dot chain line L, and is finely sheared.・ It will be cut off. Accordingly, it is impossible to knead and add the reinforcing fiber F maintained in a length that can minimize shearing and cutting and exhibit sufficient strength to the molten thermoplastic resin Q.

  Thus, in the injection molding machine 1 provided with the plasticizing apparatus 10 according to the present embodiment, the length of the sufficient strength can be exhibited by minimizing the shearing and cutting of the reinforcing fibers F that are continuously fed. Kneading with a molten thermoplastic resin in a maintained state can be performed, and reinforcing fibers can be added to the thermoplastic resin. Thereby, the molded article of desired intensity | strength can be manufactured.

  In addition, this invention is not limited to the above-mentioned embodiment, Of course, various deformation | transformation implementation is possible in the range which does not deviate from the summary of this invention. For example, the form of the thermoplastic resin Q in the above-described embodiment is not limited to the pellet form, and may be other forms such as a powder form, a granular form, a chip form, and the like. Further, the reinforcing fiber F in the embodiment described above is not limited to carbon fiber and glass fiber, but may be aramid fiber, boron fiber, or the like. Moreover, in embodiment mentioned above, although the continuous reinforcement fiber F is sent, this invention is not limited to this, For example, you may send the long reinforcement fiber F without interruption.

  DESCRIPTION OF SYMBOLS 1 ... Injection molding machine, 2 ... Injection device, 3 ... Mold, 4 ... Cavity, 10 ... Plasticizing device, 11 ... Plunger device, 12 ... Pipe, 20 ... Barrel, 21 ... Resin supply part, 22 ... Supply hole, DESCRIPTION OF SYMBOLS 23 ... Fiber supply part, 24 ... Supply hole, 30 ... Screw, 31 ... Shaft body, 32 ... Flight, 33 ... Drive part, 34 ... Screw head, 40 ... Cylinder, 41 ... Plunger, 50 ... 1st material fusion | melting part, DESCRIPTION OF SYMBOLS 51 ... 1st supply part, 52 ... 1st compression part, 53 ... 1st measurement part, 60 ... 2nd material kneading part, 61 ... 2nd supply part, 62 ... 2nd compression part, 63 ... 2nd measurement part.

Claims (3)

And barrel, housed within the barrel, the flight is provided in a spiral manner around the circumference of the shaft, and a plasticizing unit having a screw which is rotated by the drive movement unit,
A plunger device having a cylinder and a plunger that moves forward or backward in the cylinder by a drive unit;
An injection device comprising a pipe connecting the barrel and the cylinder,
The screw has a first material melting portion to which a thermoplastic resin is supplied from a proximal end side to a distal end side, and a second material kneading portion to which a continuous reinforcing fiber in the form of a thread or a belt is supplied. ,
The first material melting part has a first supply part, a first compression part, and a first metering part from the base end side toward the tip end side,
The shaft body has a diameter D1 in the first supply unit, a gradually increasing diameter in the first compression unit, and a diameter D2 larger than the diameter D1 in the first measurement unit,
The second material kneading section before SL is toward the proximal side to the distal side, and a second feed portion, a second compression unit, and a second metering section, and
The shaft body has a diameter D3 smaller than the diameter D2 in the second supply unit, a gradually increasing diameter in the second compression unit, and a diameter D4 larger than the diameter D3 in the second measurement unit,
Before SL barrel in the second supply section, and the fiber feed unit for feeding the reinforcing fibers at a position spaced at least in the screw flights one pitch equal to the distance over from the boundary between the first material melt portion An injection apparatus characterized by being provided.   An injection molding machine comprising the injection device according to claim 1. A first material melting portion that is housed in a barrel of the plasticizing apparatus and is supplied with thermoplastic resin from the base end side toward the tip end side, and a second material kneading portion that is supplied with continuous reinforcing fibers in the form of threads or belts Have
A spiral flight is provided on the outer periphery of the shaft body, and the first material melting part includes a first supply part, a first compression part, and a first metering part from the base end side toward the tip end side. and having a second material kneading section before SL is, toward the base end side to the distal side, and a second feed portion, a second compression unit, in screw is divided into a second metering section,
The shaft body has a diameter D1 in the first supply section, a gradually increasing diameter in the first compression section, a diameter D2 larger than the diameter D1 in the first metering section, and the diameter in the second supply section. is the diameter D2 smaller than the diameter D3, gradually diameter becomes large in the second compression unit, and in the second metering section is the diameter D3 larger diameter D4, the reinforcing fibers by melting the pre Kinetsu thermoplastic resin By adding, the fiber reinforced resin in a molten state is generated, the fiber reinforced resin in the molten state discharged from the plasticizing device is fed into the cylinder of the plunger device, the plunger is operated, and the fiber in the molten state is An injection method for injecting reinforced resin,
Melting the thermoplastic resin in the first material melting portion of the plasticizer;
The reinforcing fiber is fed from a position separated from the boundary between the second supply part and the first material melting part by a distance equal to or more than at least one pitch of the screw flight,
The thermoplastic resin melted in the second material kneading section and the reinforcing fiber are kneaded, the reinforcing fiber is added to the thermoplastic resin to produce a molten fiber reinforced resin, and the cylinder of the plunger device An injection method characterized by injecting the molten fiber reinforced resin fed into the interior by operating a plunger.