JP5913251B2 - Fiber-reinforced resin injection molding apparatus and injection molding method - Google Patents

Description

  The present invention relates to injection molding using a fiber reinforced resin.

  A fiber reinforced resin whose strength is increased by containing reinforcing fibers is used in various molded products. In order to obtain a molded product of fiber reinforced resin by injection molding, the thermoplastic resin is melted by rotating the screw while retreating in a cylinder, and the fiber is kneaded into the melted resin. Then, the kneaded material in which a predetermined amount is stored at the front end of the cylinder is injected from the discharge nozzle into the mold.

In the fiber reinforced resin, it is important that the fibers are uniformly dispersed with respect to the resin and the fibers are contained in a certain ratio. If the ratio of the fiber to the resin (fiber content) varies, the strength varies in each part of the molded product.
In order to make the fiber content constant, the present applicant has applied for Patent Document 1 and Patent Document 2.

These injection molding apparatuses described in Patent Document 1 and Patent Document 2 individually include a resin supply unit that supplies resin pellets into a cylinder and a fiber supply unit that supplies fibers into the same cylinder. The fiber supply unit is provided in front of the resin supply unit in the cylinder.
In Patent Document 1, the supply of fibers that have been stopped at the time of injection to advance the screw until then is continuously performed including the time of injection to suppress the occurrence of a location where fibers are not supplied in the groove of the screw. This makes the fiber content constant.

  In Patent Document 2, the screw is divided into a first stage for melting the resin and a second stage in which a fiber supply unit is arranged and kneaded the molten resin and fibers. The lead of the second stage flight is made larger than the lead. As a result, the opportunity for the fiber drop supplied from the fiber supply section to be blocked by the flight when the screw advances and retreats is reduced, and the fiber is sufficiently supplied to the groove between the flights of the second stage. To be fixed.

PCT / JP2013 / 001998 Japanese Patent Application No. 2013-084564

Although the effect described in Patent Document 1 or Patent Document 2 is effective in suppressing variations in fiber content, it is difficult to stabilize the fiber content of the fiber-reinforced resin at a constant level.
Therefore, when the mixing ratio of the resin and fiber kneaded material discharged from the nozzle at the front end of the cylinder is examined, the mixing ratio varies.

  The present invention has been made on the basis of the above problems, and improves the stability of the fiber content in the molded article by stabilizing the mixing ratio of the resin and the fiber kneaded material discharged from the nozzle. It is an object of the present invention to provide a fiber reinforced resin injection molding apparatus and a fiber reinforced resin injection molding method.

  The inventor of the present case considers that the mixing ratio of the kneaded material passing through the discharge nozzle varies due to the fluctuation in the flow rate of the molten resin that merges with the fibers supplied into the cylinder. I confirmed.

The injection molding apparatus of the present invention made on the basis of the above knowledge is formed in a cylinder provided with a discharge nozzle on the front side, a screw provided inside the cylinder so as to be rotatable and movable in the direction of the rotation axis, and the cylinder. A resin supply section for supplying a resin raw material into the cylinder through the formed resin receiving port, and a fiber supply for supplying reinforcing fibers into the cylinder through a fiber receiving port formed in front of the resin receiving port in the cylinder A part.
In the present invention, the supply amount of the reinforcing fiber supplied into the cylinder via the fiber receiving port and joined to the resin raw material flowing in from the rear is defined as a predetermined position in the axial direction of the cylinder behind the fiber receiving port. A control unit that variably controls the flow rate of the molten resin material flowing between the screw and the control unit, each of the pressure loss and temperature of the resin material flowing between the predetermined location and the screw. The flow rate is acquired using the detected value, and the supply amount of the reinforcing fiber is variably controlled according to the acquired flow rate .

  According to the present invention, the resin raw material is variably controlled in accordance with the flow rate of the molten resin raw material that flows from the rear to the joining location with the reinforcing fiber supplied into the cylinder, Even if the flow rate varies, the joining ratio of the resin raw material and the reinforcing fiber can be kept constant. Since the joining ratio is subsequently taken over in the process in which the reinforcing fiber and the resin raw material are both conveyed, the mixing ratio of the reinforcing fiber discharged from the discharge nozzle and the resin raw material can be stabilized. As a result, the stability of the fiber content of the obtained molded product can be improved.

In the injection molding apparatus of the present invention, it is preferable that a cylindrical flow path is formed between the inner periphery of a predetermined portion of the cylinder and the outer periphery of the screw.
The flow of the molten resin raw material flowing through the cylindrical flow path can be easily obtained using a mathematical expression relating to the cylindrical flow path (formula (1) described later).

In the injection molding apparatus of the present invention, the control unit obtains the flow rate using the detected values of the pressure difference and the temperature of the resin raw material flowing between the predetermined portion and the screw, and the reinforcing fiber according to the obtained flow rate. The supply amount is controlled variably .
Thereby, based on the flow rate acquired using the pressure difference and temperature of the resin raw material actually measured during the injection molding process, control according to the actual machine and the actual process can be performed.

  The control unit of the injection molding apparatus of the present invention includes, for example, a flow rate acquisition unit that acquires a flow rate of a resin raw material, a fiber supply amount acquisition unit that acquires a supply amount of reinforcing fibers using the flow rate and a predetermined fiber content rate, And a fiber supply unit controller that issues a control command for instructing the drive amount of the fiber supply unit corresponding to the supply amount.

The injection control method of the present invention includes a resin raw material that is provided in a cylinder in which a discharge nozzle is provided on the front side and a screw is disposed therein, and a reinforcing fiber that is supplied in front of the resin raw material in the cylinder. Each of the pressure loss and temperature detected values of the resin raw material flowing between the predetermined portion in the axial direction of the cylinder and the screw behind the portion where the reinforcing fiber and the resin raw material join together was used to get the flow rate of the molten resin material, in accordance with the acquired flow rate, supplied into the cylinder and variable control of the supply amount of the reinforcing fibers joins the resin material flowing from the rear that It is characterized by.

  According to the present invention, the supply amount of the reinforcing fiber is variably controlled in accordance with the flow rate of the molten resin raw material flowing from the rear to the joining point with the reinforcing fiber supplied in the cylinder, thereby Even if the flow rate varies, the joining ratio of the resin raw material and the reinforcing fiber can be kept constant. Since the joining ratio is subsequently taken over in the process in which the reinforcing fiber and the resin raw material are both conveyed, the mixing ratio of the reinforcing fiber discharged from the discharge nozzle and the resin raw material can be stabilized. As a result, the stability of the fiber content of the obtained molded product can be improved.

In the injection molding method of the present invention, the flow rate is acquired according to the pressure difference and temperature of the resin raw material flowing between the predetermined location and the screw, and the supply amount of the reinforcing fiber is variably controlled according to the acquired flow rate .
Thereby, based on the flow rate acquired using the pressure difference and temperature of the resin raw material actually measured during the injection molding process, control according to the actual machine and the actual process can be performed.

  The injection molding method of the present invention includes, for example, a resin flow rate acquisition step for acquiring a flow rate of a resin raw material, and a fiber supply amount acquisition step for acquiring a supply amount of reinforcing fibers using the acquired flow rate and a predetermined fiber content rate. And a fiber supply control step of supplying the reinforcing fibers according to the acquired supply amount.

  According to the present invention, the stability of the fiber content in the molded article can be improved by stabilizing the mixing ratio of the resin and the fiber kneaded product discharged from the nozzle.

It is a figure which shows the structure of the injection molding apparatus which concerns on 1st Embodiment of this invention. It is a figure which shows the plasticization unit of an injection molding apparatus. It is a figure which shows typically the molten state of the resin in each process of injection molding, (a) is the beginning of plasticization, (b) is the time of completion of plasticization, (c) has shown the time of completion of injection. (A) is an enlarged view of the A section shown in FIG. (B) is a graph which shows the time change of the flow volume of the molten resin which flows in into a joining location with a reinforced fiber from back. It is a block diagram which shows the part regarding control of the supply amount of a reinforced fiber among the structures of a control part. It is a flowchart which shows control of the fiber supply amount by a control part. It is a figure which shows the other example of a fiber supply apparatus. It is a figure which shows the modification of 1st Embodiment. In the plasticization unit of the injection molding device concerning a 2nd embodiment of the present invention, it is a figure showing a cylinder and a screw in the back of a fiber reception port, and a pressure sensor. (A) is a graph which shows the relationship between the pressure of molten resin, and a cylinder position. (B) is a graph which shows the relationship between the pressure of molten resin, and screw retraction amount (or plasticization time). In the plasticization unit of the injection molding device concerning a 3rd embodiment of the present invention, it is a figure showing a cylinder and a screw in the back of a fiber reception port, and a pressure sensor. It is a graph which shows the relationship between the pressure of molten resin, and a cylinder position.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
[First Embodiment]
As shown in FIG. 1, the injection molding machine 1 according to the present embodiment includes a mold clamping unit 100, a plasticizing unit 200, and a control unit 50 that controls the operation of these units.
Hereinafter, the configuration and operation of the mold clamping unit 100 and the outline of the configuration and operation of the plasticizing unit 200 will be described, and then the procedure of injection molding by the injection molding machine 1 will be described.

[Configuration of mold clamping unit]
The mold clamping unit 100 is fixedly mounted on a base frame 101 and a fixed die plate 105 to which a fixed mold 103 is attached, and a sliding member 107 such as a rail or a sliding plate by operation of a hydraulic cylinder 113. A movable die plate 111 that moves in the middle and left and right directions and has a movable die 109 attached thereto, and a plurality of tie bars 115 that connect the fixed die plate 105 and the movable die plate 111 are provided. The fixed die plate 105 is provided with a hydraulic cylinder 117 for mold clamping coaxially with each tie bar 115, and one end of each tie bar 115 is connected to a ram 119 of the hydraulic cylinder 117.
Each of these elements performs necessary operations in accordance with instructions from the control unit 50.

[Operation of mold clamping unit]
The general operation of the mold clamping unit 100 is as follows.
First, the movable die plate 111 is moved to the position of the two-dot chain line in the figure by the operation of the hydraulic cylinder 113 for opening and closing the mold, and the movable mold 109 is brought into contact with the fixed mold 103. Next, the male screw portion 121 of each tie bar 115 and the half nut 123 provided on the movable die plate 111 are engaged to fix the movable die plate 111 to the tie bar 115. Then, the pressure of the hydraulic oil in the oil chamber on the movable die plate 111 side in the hydraulic cylinder 117 is increased, and the fixed mold 103 and the movable mold 109 are tightened. After performing the mold clamping in this way, the molten resin M is injected from the plasticizing unit 200 into the cavity of the mold to form a molded product.
In addition, since the plasticizing unit 200 of this embodiment is a system which supplies the thermoplastic resin pellet P and the reinforced fiber F separately to a screw longitudinal direction so that it may mention later, the full length of the screw 10 or the full length of the plasticizing unit 200 is used. Tends to be long. For this reason, the present embodiment is configured as described above, which can be installed even in a narrow space where a mold clamping device of a toggle link system or a mold clamping cylinder on the back of a movable die plate cannot be installed. A mold clamping unit 100 having the following is shown. However, the configuration of the mold clamping unit 100 shown here is merely an example, and does not prevent other configurations from being applied or replaced. For example, in this embodiment, the hydraulic cylinder 113 is shown as the mold opening / closing actuator. However, the mold opening / closing actuator is a member that converts a rotary motion such as a ball screw or a rack and pinion into a linear motion, a servo motor, or an induction motor. A combination with an electric motor such as a motor may be used. Needless to say, it may be replaced with a toggle link type clamping unit by electric drive or hydraulic drive.

[Configuration of plasticizing unit]
As shown in FIG. 2, the plasticizing unit 200 includes a cylindrical heating cylinder 201, a discharge nozzle 203 provided on the front side of the heating cylinder 201, a screw 10 provided inside the heating cylinder 201, and a heating cylinder. A fiber supply device 213 that supplies the reinforcing fiber F into the 201 and a resin supply hopper 207 that supplies the resin pellet P into the heating cylinder 201 are provided.
The resin supply hopper 207 is connected to a resin receiving port 208 formed in the heating cylinder 201.
The fiber supply device 213 is connected to a fiber receiving port 206 formed in front of the resin receiving port 208 in the heating cylinder 201.
The plasticizing unit 200 includes a first electric motor 209 that moves the screw 10 forward or backward, a second electric motor 211 that can rotate the screw 10, a pellet supply device 215 that supplies the resin pellet P to the resin supply hopper 207, It has. Each of these elements performs necessary operations in accordance with instructions from the control unit 50. In the plasticizing unit 200, the side on which the molten resin M is injected is the front, and the side on which the raw materials (reinforcing fibers and resin pellets) are supplied is the rear.

The screw 10 has a two-stage design similar to a so-called gas vent type screw. Specifically, on the rear side of the screw 10, the first stage 21 including the supply unit 29 and the compression unit 24, the supply unit 25 connected to the first stage 21, and the second stage 22 including the compression unit 26 are provided. Designed.
In the first stage 21, the resin is melted (molten resin M), and in the second stage 22, the molten resin M and the reinforcing fibers F are mixed and dispersed. It is necessary to reduce the pressure of the molten resin M in the heating cylinder 201 that is high pressure due to compression at the terminal end (front end) of the first stage 21 in order to fill the reinforcing fibers F into the grooves of the screw 10. . For this purpose, the supply portion 25, which is a deep groove portion of the second stage 22, is indirectly connected to the terminal end (front end) of the first stage 21 through a throttle channel formed by the cylindrical portion 23.
The lead of the second flight 28 of the second stage 22 to which the reinforcing fiber F is supplied is set larger than the lead of the first flight 27. This is effective in suppressing breakage of the reinforcing fiber F. Specifically, since the helical groove length of the screw groove to the screw tip can be shortened, the molten resin M containing the reinforcing fiber F by the rotation of the screw during the plasticizing process is caused by the swirling flow in the screw groove. This is because the distance or time for receiving the shearing force can be shortened.
On the other hand, the first stage 21 makes the lead L1 smaller than the lead L2 in order to ensure the conveyance speed and plasticizing ability of the molten resin M.

Between the 1st stage 21 and the 2nd stage 22, as shown to Fig.4 (a), the cylindrical part 23 is located.
A cylindrical detection channel S is formed between the outer peripheral surface of the column part 23 and the inner peripheral surface of the heating cylinder 201. The detection flow path S is formed concentrically with the axis of the screw 10. The heating cylinder 201 is provided with pressure sensors 31 and 32 with the detection flow path S sandwiched in the axial direction.
The molten resin M melted in the first stage 21 flows into the second stage 22 through the detection flow path S between the outer periphery of the cylindrical portion 23 and the inner wall of the heating cylinder 201. As will be described later, the temperature of the molten resin M flowing through the detection flow path S and the pressure loss (pressure difference) before and after the detection flow path S are detected, and the flow rate of the molten resin M is calculated using the detected value.
Then, the temperature sensor 33 detects the temperature of the molten resin M flowing through the detection flow path S. The detection position by the temperature sensor 33 is intermediate between the detection position by the rear pressure sensor 31 and the detection position by the front pressure sensor 32 in the figure, but the position is not particularly limited. At this time, the temperature sensor 33 may be exposed to the inner wall of the heating cylinder 201 to directly measure the temperature of the molten resin M inside the heating cylinder 201, or the temperature sensor 33 may be exposed to the inner wall of the heating cylinder 201. Alternatively, the temperature of the body of the heating cylinder 201 may be measured and used as the temperature of the molten resin M.
If the temperatures at the front end side and the rear end side of the detection flow path S are different, the temperatures detected at the front end side and the rear end side may be averaged.

As shown in FIG. 8 (a), a plurality of sets of pressure sensors each including a rear pressure sensor 31 disposed relatively rearward and a front pressure sensor 32 disposed relatively frontward are provided, and the heating cylinder 201. These may be arranged in the axial direction, and a group of pressure sensors at the rear may be sequentially used in synchronization with the retraction amount of the screw 10 (see FIGS. 8A and 8B). 8A and 8B, “A” is attached to the pressure sensor used for measurement, and “N” is attached to the pressure sensor not used for measurement. This also applies to FIGS. 8C and 8D.
According to the above, since the pressure can be detected almost always at the same position across the detection flow path S in the screw 10, the flow rate of the molten resin M can be calculated with high accuracy. At this time, the distance between each pair of pressure sensors is preferably the same. Further, the circumferential positions where the pressure sensors of each set are provided may all have the same phase, or may each have a different phase. Furthermore, a plurality of sets of pressure sensors may have the same phase, and the other plurality of sets of pressure sensors may have different phases.
Further, the pressure sensor 30 is lined up in the axial direction of the heating cylinder 201 as shown in FIG. In synchronism, the pressure sensors 30 that are in a positional relationship sandwiching the cylindrical portion 23 may be sequentially selected and used (see FIGS. 8C and 8D). This also provides the same effect as in FIGS. 8A and 8B.
In the above example shown in FIG. 8, three or more pressure sensors are arranged in the axial direction of the heating cylinder 201, but a pair of pressure sensors 31 and 32 that can move in the axial direction of the heating cylinder 201 may be provided instead. it can. In that case, it is preferable that the pressure sensors 31 and 32 are moved backward so as to sandwich the cylindrical portion 23 in synchronism with the backward movement of the screw 10.

[Configuration of fiber feeder]
The fiber feeder 213 can use a screw-type or piston-type measuring feeder. In this case, the fiber supply device 213 may be directly connected to the heating cylinder 201, and the reinforcing fiber F may be supplied directly into the heating cylinder 201, or the fiber supply hopper 205 (FIG. 7B) is connected to the fiber receiving port 206. The reinforcing fiber F may be supplied from the fiber supply device 213 to the fiber supply hopper 205.

When the weighing feeder is directly connected to the heating cylinder 201, the reinforcing fiber F can be pushed into the heating cylinder 201 by the driving force of the weighing feeder. Therefore, even if the reinforcing fiber F is entangled in the fiber receiving port 206, a predetermined amount is obtained. The reinforcing fiber F can be filled in the groove of the screw 10 by the supply amount.
For maintenance such as cleaning of the fiber receiving port 206, it is preferable that the measuring feeder and the heating cylinder 201 have a structure that can be easily detached.
When using a screw-type measuring feeder, a single-screw feeder with one screw or a multi-axial feeder with a plurality of screws can be used. A multi-axis feeder that has a strong conveying force to measure and stably supply the reinforcing fiber F and can suppress slippage between the reinforcing fiber F and the feeder is preferable. A biaxial feeder with a simple structure is particularly cost-effective. Moreover, it is preferable also in terms of control.

  In addition, when using a screw-type measuring feeder in a multi-axis type feeder, even a so-called biaxial extruder-type feeder screw, in which the screw flight and the groove mesh with each other, is independent of the partition or has no partition. May be independent feeder screws without interfering with each other. In the case of using a twin screw extruder-type feeder screw, the direction of rotation of the screw may be the same or different.

The fiber supply device 213 of the present embodiment continues to supply the reinforcing fibers F through the plasticizing process and the injection process.
In the present embodiment, as shown in FIG. 1, a biaxial screw feeder 214 is provided in the heating cylinder 201 to forcibly supply the reinforcing fiber F into the groove of the screw 10. It goes without saying that there is no problem even if a single-screw screw feeder is used.
In order to increase the wettability of the resin on the surface of the reinforcing fiber F, the screw feeder may be heated by a heater (not shown). Thereby, when the temperature of the reinforcing fiber F in the screw feeder rises and the molten resin M comes into contact with the reinforcing fiber F, the temperature of the molten resin M decreases and the solidification or viscosity increases. It is possible to prevent the molten resin M from entering the inside. Thereby, the molten resin M enters between the fibers of the reinforcing fiber F, the bundle of fibers is unwound, and the dispersion of the reinforcing fiber F into the molten resin M can be promoted. Further, since the temperature of the reinforcing fiber F is increased, the molten resin M easily adheres to the reinforcing fiber F, so that the reinforcing fiber F is drawn into the cylinder from the fiber receiving port 206 as the screw 10 rotates or advances.

The reinforcing fiber F can be supplied to the biaxial screw feeder 214 by directly feeding continuous fibers, so-called roving fibers (hereinafter referred to as roving fibers), into the biaxial screw feeder 214. You may throw in the fiber (henceforth chopped fiber) of the chopped strand state cut | disconnected by the predetermined length. Alternatively, roving fibers and chopped fibers may be mixed and introduced at a predetermined ratio.
When the chopped fiber is introduced, it may be conveyed to the vicinity of the fiber insertion port of the measuring feeder with the roving fiber, and may be input to the measuring feeder immediately after cutting the roving fiber in the vicinity of the fiber input port. Thereby, since the chopped fiber which is easily scattered is not exposed until the molding machine is charged, workability can be improved.
In this embodiment, a roving cutter 218 is provided in the vicinity of the fiber insertion port of the biaxial screw feeder 214. The roving cutter 218 cuts the roving fiber into a chopped fiber, and then supplies the chopped fiber to the biaxial screw feeder 214.

  The roving cutter 218 is a rotary cutter that rotates toward the biaxial screw feeder 214. Thereby, the cut chopped fiber can be directly put into the screw groove of the biaxial screw feeder 214 without using the storage member of the reinforcing fiber F such as a hopper, using the rotational force of the cutter. As a result, the chopped fibers can be fed into the biaxial screw feeder 214 with little entanglement immediately after cutting, so that the chopped fibers are efficiently bited into the biaxial screw feeder 214 and stabilized from the biaxial screw feeder 214. Thus, the chopped fiber can be supplied into the groove of the screw 10.

[Operation of plasticizing unit]
The general operation of the plasticizing unit 200 is as follows. Please refer to FIG. 1. When the screw 10 provided in the heating cylinder 201 is rotated, the reinforcing fiber F supplied from the fiber supply device 213 through the fiber receiving port 206 and the resin supply hopper 207 are shown. The pellets (resin pellets P) made of thermoplastic resin supplied through the resin receiving port 208 are sent out to the discharge nozzle 203 side on the front side of the heating cylinder 201. In this process, the heated and melted resin pellets P (molten resin M) are kneaded with the reinforcing fibers F and then to the cavity formed between the fixed mold 103 and the movable mold 109 of the mold clamping unit 100. A predetermined amount is injected. Needless to say, the basic operation of the screw 10 is to perform injection by moving forward after plasticizing while the screw 10 is moved backward. In addition, a heater (not shown) is provided on the outer periphery of the heating cylinder 201 in order to melt the resin pellets P.

[Injection molding procedure]
The injection molding machine 1 including the above elements performs injection molding according to the following procedure.
As is well known, the injection molding is performed by closing the movable mold 109 and the fixed mold 103 and clamping at a high pressure, and plasticizing the resin pellet P by heating and melting in the heating cylinder 201. A plasticizing step, an injection step of injecting and filling the plasticized molten resin M into a cavity formed by the movable mold 109 and the fixed mold 103, and until the molten resin M filled in the cavity is solidified. A holding process for cooling, a mold opening process for opening the mold, and a taking-out process for taking out the molded product that has been cooled and solidified in the cavity are carried out, and the above-mentioned processes are performed sequentially or partially in parallel. Completes one cycle.

The plasticizing step and the injection step will be described in order with reference to FIG.
[Plasticization process]
In the plasticizing step, the resin pellets P are supplied from the resin supply hopper 207 at the rear of the heating cylinder 201 into the heating cylinder 201 through the resin receiving port 208 and from the fiber supply device 213 through the fiber receiving port 206. F is supplied into the heating cylinder 201.
In the plasticizing step, the supply of the resin pellets P and the reinforcing fibers F is continuously performed.
At the beginning of plasticization, the screw 10 is located at the front end of the heating cylinder 201, and is retracted while rotating the screw 10 from the initial position (FIG. 3 (a) "Begin plasticization").
The resin pellet P supplied between the screw 10 and the heating cylinder 201 is gradually melted while being heated by receiving the shearing force by rotating the screw 10 and conveyed forward. The molten resin M transported to the position of the fiber supply device 213 is transported further forward while being kneaded with the reinforcing fiber F supplied from the fiber supply device 213, and collected in front of the screw 10. In the process, the bundle of reinforcing fibers F is loosened and dispersed in the molten resin M.
As the molten resin M is conveyed forward, the pressure of the molten resin M is gradually increased. The screw 10 is moved backward while balancing the pressure of the molten resin M stored in front of the screw 10 with the back pressure that suppresses the screw 10 from moving backward.
When the necessary amount of the molten resin M is accumulated in this way, the rotation and retreat of the screw 10 are stopped (FIG. 3 (b) “plasticization complete”).

  FIG. 3 schematically shows the state of the resin (resin pellet P, molten resin M) and the reinforcing fiber F in four stages of “unmelted resin”, “resin melt”, “fiber dispersion”, and “fiber dispersion complete”. Shown separately. At the stage of “plasticization completion” (FIG. 3B), “fiber dispersion completion” in front of the screw 10 indicates a state in which the reinforcing fibers F are dispersed in the molten resin M and used for injection. “Fiber dispersion” indicates that the supplied reinforcing fibers F are dispersed in the molten resin M as the screw 10 rotates. Further, “resin melting” indicates that the resin pellet P is melted by receiving a shearing force, and “unmelted resin” is subjected to the shearing force but has not yet been melted.

[Injection process]
In the subsequent injection process, the screw 10 is advanced as shown in FIG. At this time, a backflow prevention valve (not shown) provided at the tip of the screw 10 is closed. When the screw 10 is advanced, the pressure (resin pressure) of the molten resin M dispersed in the reinforcing fibers F accumulated in the front of the screw 10 is increased, and the molten resin M in which the reinforcing fibers F are dispersed is discharged from the discharge nozzle 203 into the cavity. It is discharged toward.

[Main features of this embodiment]
Hereinafter, main features of the present embodiment will be described.
In the fiber reinforced resin, in order to obtain design strength, it is important that the reinforcing fibers F are uniformly dispersed in the resin and the resin and the reinforcing fibers F are contained in a certain ratio.
In the fiber reinforced resin molded product, the fiber content is determined based on the required strength design.
Hereinafter, the fiber content refers to the weight of fiber contents based on weight. The weight fiber content is determined by the ratio of the weight of the resin in the fiber reinforced resin and the weight of the reinforced fiber F contained in the resin.
In place of the weight fiber content, a volume of fiber contents based on volume may be used.

In order to improve the stability of the fiber content, it is necessary to stabilize the mixing ratio of the mixture of the molten resin M and the reinforcing fiber F discharged from the discharge nozzle 203.
By the way, the reinforcing fiber F is joined to the molten resin M in the groove of the screw 10 located immediately below the fiber receiving port 206 (the joining point J) for supplying the reinforcing fiber F into the heating cylinder 201.
The supplied reinforcing fibers F adhere to the molten resin M, are gradually loosened by being kneaded with the molten resin M by the screw 10, and are dispersed in the molten resin M. In the process, the reinforcing fiber F is captured by the molten resin M having a predetermined viscosity, and is conveyed forward together with the molten resin M.
Here, all the reinforcing fibers F supplied from the fiber supply device 213 join the molten resin M at the joining point J and are transported to the front of the screw 10 without flowing back in the groove of the screw 10, so that they are discharged. The mixing ratio in the kneaded product is almost determined by the ratio (merging ratio) between the molten resin M and the reinforcing fibers F that merge.
Then, if the merging ratio of the molten resin M and the reinforcing fiber F varies, the ratio variation affects the mixing ratio of the mixture discharged from the discharge nozzle 203.

Even if the supply amount of the reinforcing fiber F supplied from the fiber supply device 213 is constant, if the supply amount (flow rate) of the molten resin M that joins the reinforcing fiber F varies, the molten resin M and the reinforcing fiber F The merge ratio varies.
In order to calculate the flow rate of the molten resin M at the junction J, the pressure loss (pressure difference) and temperature of the molten resin M flowing through the detection flow path S are detected.
Here, if the flow rate at the junction J can be calculated appropriately using the pressure difference and temperature of the molten resin M at the junction J, the detection flow path S need not be used.
However, when the pressure is measured at the junction J, the fiber supply device 213 forcibly fills the molten resin M in the groove of the screw 10 with the reinforcing fiber F, so that the pressure of the molten resin M becomes irregular. fluctuate. For this reason, the measured pressure value of the molten resin M is affected by the filling of the reinforcing fibers F, and the fluctuation of the flow rate of the molten resin M that flows into the joining point J from the rear and joins the reinforcing fibers F is appropriately captured. It is difficult.
Therefore, it is necessary to detect the pressure difference of the molten resin M behind the junction J (the same behind the fiber receiving port 206).
As described above, the pressure difference of the molten resin M is detected in the detection flow path S that is separated backward from the joining point J to the extent that the influence of the forced filling by the fiber supply device 213 is not greatly received and the melted resin flows. Determined as a point.

  Moreover, since the cylindrical part 23 is located at the terminal end (front end) of the first stage 21 responsible for the melting of the resin pellets P, the state of the resin located around the cylindrical part 23 is shown in FIGS. Are melted through a plasticizing process and an injection process. That is, what flows through the detection flow path S around the cylindrical portion 23 is a completely molten resin or a molten resin containing a semi-molten resin that has been sufficiently softened even if it does not reach complete melting.

  From the above, the resin flowing through the detection flow path S does not include the large lumps of the reinforcing fibers F and the resin pellets P, and has a uniform fluidity, so that correction or the like is not made based on the fluid theory. The flow rate Q can be easily derived. That is, the flow rate Q can be appropriately calculated based on the difference between the inlet pressure P1 and the outlet pressure P2 of the detection flow path S and the temperature T of the molten resin M that affects the viscosity of the molten resin M. .

Here, since the detection flow path S is cylindrical, the flow of the molten resin M in the detection flow path S conforms to Expression (1) for obtaining the flow rate Q of the cylindrical flow path. Please also refer to FIG.
Q = π (R2 + R1) (R2-R1) ³ (P1-P2) / (12ηL) (1)
R1: Inner radius of the detection channel S R2: Outer radius of the detection channel S P1: Pressure on the inlet side of the detection channel S P2: Pressure on the outlet side of the detection channel S η: Viscosity of the molten resin M L: Detection Distance from the entrance to the exit of the flow path S The above R1, R2, and L are known, and η is the material of the resin used (for example, polypropylene, polyethylene, etc.) and the temperature T detected by the temperature sensor 33 Determined from.
P1 is detected by the rear pressure sensor 31, and P2 is detected by the front pressure sensor 32.

The pressure sensors 31 and 32 and the temperature sensor 33 continuously detect the pressure difference and temperature of the molten resin M flowing through the detection flow path S, and calculate the flow rate Q of the molten resin M from the equation (1).
Part of the temporal change in the flow rate Q of the molten resin M thus obtained is shown in FIG.
As shown in FIG. 4B, a maximum point and a minimum point can be recognized in the flow rate Q of the molten resin M. The flow rate Q changes substantially periodically so as to correspond to the cycle time of injection molding.
The fluctuation of the flow rate Q as described above corresponds to a change in the pressure state of the molten resin M in the process of injection molding. For example, during the plasticizing process, as the molten resin M is transported forward, the pressure is increased by the pump characteristics of the screw, so that the pressure of the molten resin M flowing through the detection flow path S gradually increases. In addition, when the plasticizing process is completed, the pumping effect due to the screw rotation is lost, so the pressure of the molten resin M decreases.
FIG. 4B schematically shows the temporal change of the molten resin M, and the actual flow rate Q fluctuates up and down every moment.

As described above, the flow rate Q of the molten resin M that flows through the detection flow path S and flows into the joining point J varies. Control is performed such that the supply amount Q _F (supply amount per unit time) of the reinforcing fiber F follows the temporal change in the flow rate Q as shown by a broken line in FIG.

In the present embodiment, the supply of reinforcing fibers F, since use of the fiber feed device 213 that requires a driving force, by controlling the drive amount, for variably controlling the supply amount Q _F.
Advance were tested and simulation, it is preferable to create a table data indicating the correspondence between the supply amount Q _F and the driving amount of the fiber feed device 213.

The control unit 50 performs the following control as described above.
As shown in FIG. 5, the control unit 50 includes a resin flow rate calculation unit 51 that calculates the flow rate Q of the molten resin M, and a fiber supply amount calculation unit 52 that calculates the supply amount Q _F of the reinforcing fibers F according to the flow rate Q. When, and a fiber supply controller 53 issues a control command for instructing the driving amount of the fiber feed device 213 in accordance with the supply amount Q _F.
The control unit 50 is configured by a computer program or an electric circuit / electronic circuit incorporating a circuit element.

With reference to FIG. 6, operation | movement of each part 51-53 of the control part 50 is demonstrated.
When the control of the fiber supply amount by the control unit 50 is started, the resin flow rate calculation unit 51 is based on the detection values obtained from the rear pressure sensor 31, the front pressure sensor 32, and the temperature sensor 33, and Expression (1). The flow rate Q is calculated (step S1 for calculating the flow rate of the molten resin).

Next, the fiber supply amount calculation unit 52 calculates the supply amount Q _F of the reinforcing fiber F necessary for realizing a predetermined fiber content with respect to the flow rate Q calculated by the resin flow rate calculation unit 51 ( Fiber supply amount calculation step S2). The supply amount Q _F can be obtained by multiplying the flow rate Q by the fiber content. The supply amount Q _F can be obtained using a predetermined correction value in addition to the flow rate Q and the fiber content.

Then, the fiber supply control unit 53 sends a control command for instructing driving of the fiber feed device 213 corresponding to the supply amount Q _F calculated by the fiber feed amount calculating section 52 to the fiber feed device 213 (fiber supply control Step S3). The driving amount of the fiber supply device 213 is controlled based on the control command.
When the fiber feeder 213 is a screw feeder, the number of rotations of the screw feeder is controlled by a control command.
By controlling the drive amount of the fiber supply device 213, the supply amount Q _F of the reinforcing fiber F by the fiber supply device 213 is controlled.

When step S3 is completed, the process returns to step S1. The resin flow rate calculation unit 51 continuously outputs the calculation result of the flow rate Q according to the equation (1) while observing the pressure difference and temperature of the molten resin M flowing through the detection flow path S by the sensors 31 to 33. Thereafter, step S2 and step S3 are performed in the same manner as described above.
The above steps S1 to S3 are continuously performed only through the plasticizing process or through the plasticizing process and the injection process.

Controlled by, as shown in FIG. 4 (b), with respect to the temporal variation of the flow rate Q of the molten resin M, supply amount Q _F to follow.
That is, when the flow rate Q of the molten resin M is large, a large amount of reinforcing fiber F is supplied, and when the flow rate Q of the molten resin M is small, a small amount of reinforcing fiber F is also supplied.
The flow rate Q of the molten resin M that flows through the detection flow path S is equal to the flow rate of the molten resin M that flows into the junction J from behind.
Therefore, to be a constant confluence percentage of that supply quantity Q _F of the reinforcing fibers F in accordance with the variation of the flow rate Q of the molten resin M is controlled, the reinforcing fibers F at the joining portion J and the molten resin M it can.

As described above, in the present embodiment, the supply amount QF of the reinforcing fiber _F is variably controlled according to the flow rate Q of the molten resin M flowing from the rear to the joining point J with the reinforcing fiber F. Even if the flow rate Q of the molten resin M fluctuates, the joining ratio of the molten resin M and the reinforcing fibers F can be kept constant. Thereafter, the joining ratio is inherited even in the process in which both the reinforcing fiber F and the molten resin M are conveyed, so that the mixing ratio of the reinforcing fiber F and the molten resin M discharged from the discharge nozzle 203 can be stabilized. As a result, the stability of the fiber content of the obtained molded product can be improved.

Further, in the present embodiment, the pressure difference and temperature of the molten resin M flowing in the detection flow path S between the columnar portion 23 located between the first stage 21 and the second stage 22 of the screw 10 and the heating cylinder 201. Is used to calculate the flow rate Q of the molten resin M.
Here, since the melting of the resin is completed in the first stage 21, the resin is melted at the position of the cylindrical portion 23.
In addition, the reinforcing fiber F does not enter the detection flow path S because the cylindrical portion 23 is positioned behind the fiber receiving port 206 through the plasticizing process and the injection process.
Therefore, since only the molten resin M flows through the detection flow path S, the flow rate Q of the molten resin M flowing through the detection flow path S can be properly grasped. According to the flow rate Q, the supply amount Q _F of the reinforcing fiber F can be appropriately controlled. Further, since the reinforcing fibers F do not enter the pressure sensors 31 and 32, it is possible to prevent the life of the pressure sensors 31 and 32 from being worn by the reinforcing fibers F from being shortened.

  By the way, the pressure measurement value in the groove of the screw 10 due to the rotation of the screw 10 fluctuates with one rotation of the screw 10 as one cycle. Specifically, the measured pressure waveform has a sawtooth shape. Therefore, as the pressure value for calculating the flow rate Q of the molten resin M, either the upper limit value, the lower limit value, or the average value of the sawtooth may be used.

[Second Embodiment]
In the present embodiment, the same injection molding machine 1 as in the first embodiment is used. However, even if the position of the detection flow path S with respect to the heating cylinder 201 changes as the cylindrical portion 23 moves due to the retraction of the screw 10, the detection flow path S is sandwiched between the two pressure sensors as much as possible to melt. Instead of providing a plurality of pressure sensors so as to detect the pressure of the resin M (FIG. 8), the flow rate Q of the molten resin M is estimated based on the pressure measured at at least two locations behind the detection flow path S. . Below, it demonstrates centering on a different point from 1st Embodiment.
Also in this embodiment, the pressure sensors 31 and 32 are fixed to the heating cylinder 201 as in the first embodiment, but both the pressure sensors 31 and 32 (FIG. 9) are provided behind the detection flow path S. . More specifically, the pressure sensors 31 and 32 are located slightly behind the position of the cylindrical portion 23 when the screw 10 is retracted to the maximum.
In the present embodiment, the screw 10 is integrated with the screw 10 from the difference between the pressure P1 of the pressure sensor 31 positioned relatively rearward and behind the detection flow path S and the pressure P2 of the pressure sensor 32 positioned relatively forward. Thus, the pressure P3 of the virtual point X3 located in front of the detection flow path S that moves backward together with the screw 10 is estimated by extrapolation, for example (FIG. 10A).
The relative position between the pressure sensors 31, 32 provided in the heating cylinder 201 and the detection flow path S is uniquely determined by the mechanical assembly state. In general, the pressure of the molten resin M at the time of plasticization on the front end side of the first stage 21 is approximately as it goes forward due to the pump characteristics of the screw, that is, as it becomes closer to the detection flow path S when viewed from the pressure sensors 31 and 32. It is known to rise proportionally. Using this, the detection flow path S is based on the difference between the pressure P1 and the pressure P2 and the relative position between the pressure sensor 31 and the detection flow path S (or the relative position between the pressure sensor 32 and the detection flow path S). The pressure P3 at the virtual point X3 located in front of is estimated, for example, by extrapolation (FIG. 10B).
In the detection flow path S that retreats together with the screw, plasticization proceeds, that is, as the retraction amount of the screw 10 increases (or as the plasticization time elapses), the detection flow path S approaches the pressure sensor 32. This means that the value of the pressure P3 approaches the value of the pressure P2 (FIG. 10 (b)).
As described above, the pressure P3 of the virtual point X3 located in front of the detection flow path S can be obtained following the retreat of the screw 10.
By the way, it is preferable that the 2nd stage supply section (fiber receiving port 206) on the front side of the detection flow path section is decompressed to about atmospheric pressure in order to fill the reinforcing fibers. In this case, in the present embodiment, the flow rate Q can be calculated using the pressure difference between the pressure P3 and the atmospheric pressure.
Further, if the pressure is measured by providing another pressure sensor at a certain position of the heating cylinder 201 located on the front side from the detection flow path S through the plasticizing process from the start of the retreat of the screw 10 to the completion of the retreat, As a pressure difference before and after sandwiching the detection flow path S as in the first embodiment, the pressure difference between the measurement pressure of the pressure sensor and the pressure P3 can be obtained. By calculating the flow rate Q using the pressure difference, the same effect as described in the first embodiment can be obtained, and the calculation accuracy of the flow rate Q can be further improved.

[Third Embodiment]
Also in this embodiment, the injection molding machine 1 of the first embodiment is used. However, the flow rate Q of the molten resin M is estimated based on the pressure measured by one pressure sensor 31 (FIG. 11) at one location behind the detection flow path S. Below, it demonstrates centering on a different point from 1st Embodiment.
The pressure sensor 31 is fixed to the heating cylinder 201 as in the first embodiment.
The relative position between the pressure sensor 31 provided in the heating cylinder 201 and the detection flow path S is uniquely determined by the mechanical assembly state. In general, the pressure of the molten resin M at the time of plasticization on the front end side of the first stage 21 is substantially proportional as it goes forward due to the pump characteristics of the screw, that is, as it becomes closer to the detection flow path S as viewed from the pressure sensor 31. Is known to rise. Utilizing this, a change in the pressure P1 is measured in advance by experiments, and the pressure P1 and the relative position between the pressure sensor 31 and the detection flow path S are positioned in front of the detection flow path S. The pressure P3 at the virtual point X3 is estimated by extrapolation, for example (FIG. 12).
Thus, the pressure P3 at the virtual point X3 before the detection flow path S can be obtained following the retreat of the screw 10. At this time, when the supply unit (fiber receiving port 206) of the 2nd stage is reduced to about atmospheric pressure, the flow rate Q can be calculated using the pressure difference between the pressure P3 and the atmospheric pressure. Further, if the pressure is measured by providing another pressure sensor at a certain position of the heating cylinder 201 located on the front side from the detection flow path S through the plasticizing process from the start of the retreat of the screw 10 to the completion of the retreat, As a pressure difference before and after sandwiching the detection flow path S as in the first embodiment, the pressure difference between the measurement pressure of the pressure sensor and the pressure P3 can be obtained. By calculating the flow rate Q using the pressure difference, the same effect as described in the first embodiment can be obtained, and the calculation accuracy of the flow rate Q can be further improved.

This embodiment can be modified in various ways.
Since the detection flow path S is cylindrical, the flow rate Q can be obtained using Equation (1), but the shape of the detection flow path S is not limited to the cylindrical shape. For example, even if the detection flow path S is formed in a shape corresponding to a protrusion or a depression formed on a part of the outer peripheral surface of the cylindrical portion 23, from the correlation between the pressure difference and the temperature and the flow rate through experiments and simulations. The flow rate Q of the molten resin M flowing through the detection flow path S can be obtained.
Further, not only the cylindrical portion 23 but also a space formed between the inner peripheral surface at a predetermined position in the axial direction of the heating cylinder 201 and the outer periphery (for example, the flight top surface) of the screw 10 is used as the detection flow path S. However, the present invention allows.
Therefore, the cylindrical portion 23 is not essential to the present invention.
Here, even if the cylindrical portion 23 is formed in the screw 10, the position is not limited between the first stage 21 and the second stage 22.

In the present embodiment, when the supply of the reinforcing fiber F is continued through the plasticizing step and the injection step, the supply amount Q _F is controlled to follow the flow rate Q through the plasticizing step and the injection step. The merging ratio can be kept constant throughout the period. In this way, since the kneaded material having a constant mixing ratio can be continuously injected, the effect of improving the stability of the fiber content is the highest.
However, the present invention is, stop the supply of the reinforcing fibers F in some periods of the plasticizing step and injection step, and stops the control of the supply amount Q _F at a part of the period, the supply amount previously determined It is allowed to supply the reinforcing fiber F. Even in such a case, the mixing ratio can be stabilized by controlling the supply amount Q _F of the reinforcing fiber F in the remaining period, which can contribute to an improvement in the stability of the fiber content.

Further, in this embodiment, immediately after the flow rate Q is calculated by the resin flow rate calculation unit 51, the supply amount Q _F of the reinforcing fiber _F is calculated, but the molten resin present around the cylindrical portion 23 at the time of calculation of the flow rate Q. The response of the supply amount Q _F of the reinforcing fiber F to the flow rate Q may be delayed according to the time required for M to reach the joining point J (time required for arrival) (see the one-dot chain line in FIG. 4B). ).
In order to perform the control as described above, the temporal change in the flow rate Q is stored, and the supply amount Q _F of the reinforcing fiber _F is calculated according to the flow rate Q detected at a time traced back by the required arrival time. Good.

As described above, in the present embodiment, the flow rate Q is calculated using the pressure difference and the temperature at a predetermined location of the molten resin M flowing from the rear to the joining location J, and the supply amount Q of the reinforcing fibers F according to the flow rate Q. _F is controlled variably.
Therefore, based on the flow rate Q calculated from the pressure difference and temperature of the molten resin M actually measured during the injection molding process, it is possible to perform control according to the actual machine and the actual process. The flow rate Q set in advance based on experiments and simulations is acquired and used for controlling the supply amount Q _F of the reinforcing fiber F.
In addition, by performing an experiment in advance, for example, by setting the flow rate Q for one cycle of injection molding in the table data, it is possible to control to withstand practical use without calculating the flow rate Q from the on-time measured value. be able to.

As a form of the apparatus which supplies the reinforced fiber F, the structure shown to Fig.7 (a) or the structure shown to FIG.7 (b) is also employable.
Fig.7 (a) shows the single axis | shaft type screw feeder 216 as a fiber supply apparatus. Thus, the reinforcing fiber F can be supplied by providing the single screw feeder 216 in communication with the fiber receiving port 206. The reinforcing fiber F is forcibly supplied into the groove of the screw 10 by the single-screw screw feeder 216.

On the other hand, when the reinforcing fiber F is supplied through the fiber supply hopper 205, a belt feeder 217 as shown in FIG. 7B can be used as the fiber supply device 213. By adjusting the conveyance speed of the belt feeder 217, the reinforcing fiber F can be supplied to the fiber supply hopper 205 by a predetermined amount.
Here, when the reinforcing fiber F is supplied from the belt feeder 217 to the fiber supply hopper 205, the supply amount that does not entangle the reinforcing fiber F in the fiber receiving port 206, specifically, the fiber receiving port 206 is filled. By restricting the supply amount of the reinforcing fiber F to such an extent that it does not occur, the reinforcing fiber F can be filled in the screw 10 without closing the inside of the fiber receiving port 206. Thereby, since it can supply in the groove | channel of the screw 10 without giving a load to the reinforced fiber F, the fiber breakage before throwing in in the groove | channel of the screw 10 can be suppressed.

Moreover, the screw used by this invention is not limited to the screw 10 of the said embodiment, A various form can be taken. The screw of the present invention is not limited to the two-stage type including the first stage 21 and the second stage 22.
Moreover, although the screw 10 is provided with the 1st flight 27 and the 2nd flight 28 from which a lead differs, the screw of this invention may be provided with 1 type of flight which has a single lead.
If the screw shape changes, the molten state of the resin also changes. For this reason, the present invention allows the molten resin M passing through the detection flow path S to be not completely melted and to contain unmelted residue that does not hinder the detection of the pressure difference and temperature.

Moreover, neither the resin raw material nor the reinforcing fiber applied to the present invention is particularly limited.
As the resin raw material, known resins such as general-purpose resins such as polypropylene and polyethylene and engineering plastics such as polyamide and polycarbonate can be widely used.
As the reinforcing fiber, known fibers such as glass fiber, carbon fiber, bamboo fiber, hemp fiber can be widely used.

  In addition to the above, the configurations described in the above embodiments can be selected or modified as appropriate to other configurations without departing from the gist of the present invention.

  The present invention can be applied to extrusion molding in addition to injection molding. The extrusion molding apparatus can be configured in the same manner as the injection molding apparatus of the present invention except that the screw is not advanced or retracted.

DESCRIPTION OF SYMBOLS 1 Injection molding machine 10 Screw 21 1st stage 22 2nd stage 23 Column part 24 Compression part 25 Supply part 26 Compression part 27 1st flight 28 2nd flight 29 Supply part 31 Back pressure sensor 32 Front pressure sensor 33 Temperature sensor 50 Control Unit 51 Resin flow rate calculation unit (resin flow rate acquisition unit)
52 Fiber supply amount calculation unit (fiber supply amount acquisition unit)
53 Fiber Supply Control Unit 100 Clamping Unit 101 Base Frame 103 Fixed Mold 105 Fixed Die Plate 107 Sliding Member 109 Movable Mold 111 Movable Die Plate 113 Hydraulic Cylinder 115 Tie Bar 117 Hydraulic Cylinder 119 Ram 121 Male Threaded Section 123 Nut 200 Plasticization Unit 201 Heating cylinder (cylinder)
203 Discharge nozzle 205 Fiber supply hopper 206 Fiber receiving port 207 Resin supply hopper (resin supply unit)
208 Resin receiving port 209 First electric motor 211 Second electric motor 213 Fiber supply device (fiber supply unit)
214 Biaxial screw feeder 215 Pellet feeder 216 Single screw screw feeder 217 Belt feeder 218 Roving cutter F Reinforcing fiber J Merge location L1 First lead L2 Second lead P Resin pellet (resin raw material)
Q flow rate Q _F supply amount S detection flow path S1 flow rate calculation step (flow rate acquisition step)
S2 Fiber supply amount calculation step (fiber supply amount acquisition step)
S3 Fiber supply control step

Claims (5)

A cylinder provided with a discharge nozzle on the front side;
A screw provided inside the cylinder so as to be rotatable and movable in the direction of the rotation axis;
A resin supply section for supplying a resin raw material into the cylinder via a resin receiving port formed in the cylinder;
A fiber supply unit for supplying reinforcing fibers into the cylinder through a fiber receiving port formed on the front side of the resin receiving port in the cylinder;
A supply amount of the reinforcing fibers supplied into the cylinder through the fiber receiving port and joined to the resin raw material flowing in from the rear is set to a predetermined position in the axial direction of the cylinder behind the fiber receiving port. A controller that variably controls according to the flow rate of the molten resin raw material flowing between the screws ,
The controller is
The flow rate is acquired using detected values of the pressure loss and temperature of the resin raw material flowing between the predetermined portion and the screw, and the supply amount of the reinforcing fiber is variable according to the acquired flow rate. To control,
A fiber-reinforced resin injection molding apparatus characterized by the above. Between the outer periphery of the inner periphery and the screw of said predetermined portion of said cylinder, a cylindrical flow path is formed,
The fiber-reinforced resin injection molding apparatus according to claim 1. The controller is
A flow rate acquisition unit for acquiring the flow rate of the resin raw material;
A fiber supply amount acquisition unit that acquires the supply amount of the reinforcing fibers using the flow rate and a predetermined fiber content;
A fiber supply unit control unit that issues a control command that instructs a drive amount of the fiber supply unit corresponding to the supply amount;
An injection molding apparatus for fiber reinforced resin according to claim 2 . An injection nozzle is provided on the front side, and injection molding is performed using a resin raw material supplied into a cylinder in which a screw is disposed inside and a reinforcing fiber supplied in front of the resin raw material into the cylinder. A method,
Using the detected values of the pressure loss and temperature of the resin raw material flowing between the screw and the predetermined location in the axial direction of the cylinder behind the location where the reinforcing fiber and the resin raw material merge, Acquire the flow rate of the resin raw material, and according to the acquired flow rate,
The supplied into the cylinder and variable control of the supply amount of the reinforcing fibers to be merged into the resin material flowing from the rear,
An injection molding method of a fiber reinforced resin characterized by the above. A resin flow rate obtaining step for obtaining the flow rate of the resin raw material;
A fiber supply amount acquisition step of acquiring the supply amount of the reinforcing fibers using the acquired flow rate and a predetermined fiber content;
A fiber supply control step of supplying the reinforcing fibers according to the acquired supply amount,
An injection molding method for a fiber reinforced resin according to claim 4 .

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