JP4139745B2 - Resin raw material supply device for synthetic resin molding machine and operation method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is an apparatus for supplying a resin raw material to a synthetic resin molding machine, and more specifically, while quickly removing water vapor and gas generated during heating and conveying the resin raw material with a heating cylinder comprising a screw and a casing, The present invention relates to a supply device that does not generate a silver strip or a cavity in a synthetic resin molded product by a molding machine, and an operation method thereof.
[0002]
[Prior art]
In the production of synthetic resin molded products by injecting molten resin into a synthetic resin molding machine (extrusion molding machine, injection molding machine) while transporting and melting the resin raw material with a heating cylinder consisting of a screw and casing, In the casing of the heating cylinder that is the melting region, water vapor due to moisture adhering to the resin raw material, or decomposition gas or volatile gas due to the resin component (monomer, oligomer or solvent) is generated.
[0003]
If such water vapor and gas are not sufficiently removed before reaching the molding machine, silver strips and cavities and the like are generated in the synthetic resin molded product produced by the molding machine, causing a product defect.
[0004]
Patent Document 1 discloses a gas or moisture removing device for a synthetic resin molding machine so as not to cause such product defects. In Patent Document 1, an inner cylinder part (material introduction pipe) and an outer cylinder part (cylindrical lower body) surrounding the inner cylinder part (material introduction pipe) are provided at a resin raw material inlet (material supply inlet) of a heating cylinder constituting the molding machine. The heating cylinder is sucked and exhausted through the raw material charging port by a suction air source connected to the outer cylindrical portion while charging the resin raw material from the inner cylindrical portion to the heating cylinder.
[0005]
Patent Document 2 is a further improvement, in which undried resin pellets are supplied into a cylinder of an injection molding machine to perform the first injection, and the quality of the resin purge injected after a predetermined time has elapsed from the first injection. A method of performing injection molding by performing injection with an optimum deposition amount per unit shot obtained by inspection is disclosed.
[0006]
[Patent Document 1]
Japanese Utility Model Publication No. 7-2182 [Patent Document 2]
WO99 / 33630 gazette [0007]
[Problems to be solved by the invention]
The gas, water vapor and the like (hereinafter referred to as “gas”) removal device disclosed in Patent Document 1 is a gas generated in a casing when the resin raw material is heated and melted while being conveyed toward a molding machine with a screw feeder. However, there are still problems to be solved as follows.
[0008]
That is, as the continuously supplied resin raw material is conveyed by the heating cylinder toward the injection port (nozzle) to the former molding machine, the inside of the casing of the heating cylinder is closed by the molten resin. Therefore, the gas generated at the front side portion is not sufficiently exhausted.
[0009]
As described above, if the exhaust in the casing is not sufficiently performed, the molten resin is injected into the molding machine while containing the gas, which causes the occurrence of silver strips and cavities, and product defects still occur. There was a thing. In addition, in the case of the method of Patent Document 2, since injection is always performed with an optimum deposition amount, such a problem does not occur, but it is necessary to perform resin purge many times for each molding process, and production efficiency is improved. There was a problem of getting worse.
[0010]
Further, in this type of conventional resin molding machine, it is common sense that the molding machine is operated with a maximum supply amount of resin material, that is, with a filling rate of almost 100%, in order to stabilize the weighing process. Had been done.
[0011]
On the other hand, in order to prevent the resin raw material from being caught in the molding machine, it has been proposed not to fill the molding machine, and also from the viewpoint of suction and discharge of gas, the resin is formed so as to generate a void in the molding machine. The idea that it is desirable to supply raw materials is becoming known.
[0012]
Therefore, the inventor pays attention to the concept of filling rate and porosity (also called hunger rate), finds an optimal porosity value that is optimal for gas suction, and then determines the porosity to be an optimized numerical value. It was a new technical problem to stabilize the air gap and make the air gap uniform without bias.
[0013]
The present invention has been proposed in view of such circumstances, and the gas generated in the casing of the heating cylinder can be quickly and rapidly provided that the heating cylinder in the weighing process is maintained in an optimal gap state. A resin raw material supply device for a synthetic resin molding machine that can evacuate without delay and can efficiently produce synthetic resin molded products without causing quality defects such as silver stripes and cavities in the products produced by the molding machine. It is intended to provide.
[0014]
Here, the filling rate and the hunger rate are calculated by the following formulas.
[0015]
Filling rate = Actual raw material supply to molding machine / Maximum raw material supply to molding machine Hunger rate = 1-Filling rate
[Means for Solving the Problems]
In order to solve the above problems, a resin raw material supply device for a synthetic resin molding machine according to claim 1 is a resin raw material installed at a raw material inlet of a heating cylinder of a synthetic resin molding machine comprising a screw and a casing. The supply device has the following configuration.
[0017]
That is, the raw material charging port is provided with a raw material charging inner cylinder part and an exhaust outer cylinder part surrounding the inner cylindrical part and connected to the gas suction device. A charge tank storing a resin raw material in which the supply amount for one shot to be replenished to the casing during the process is stored in advance, and the resin raw material stored in the charge tank through a raw material charging inner cylinder portion of the raw material charging port A raw material feeder that is on / off controlled to be supplied into the casing, a distance sensor that is provided in the exhaust outer cylinder portion and detects the presence or absence of the raw material on the screw surface near the raw material inlet, and raw material supply Supply device control means for on / off control of the machine, the supply device control means within the period of the weighing process after the measurement start signal is output until the measurement completion signal is output, distance In accordance with the detection signal of the capacitors, the raw material supply machine by turning on / off control, and intermittently replenished constructed by dividing one shot of the resin material stored in the charge tank in the casing.
[0018]
According to such a configuration, since the raw material can be charged for each shot, the inside of the heating cylinder can be maintained at a constant starvation rate. And by including a gap with a certain starvation rate, it becomes easier to sequentially discharge the gas generated in the casing of the heating cylinder by the gas suction device, and the gas stays in the molten resin causing silver strips and cavities, etc. Can be prevented. In particular, since the presence or absence of the raw material on the screw surface is detected by the distance sensor, the raw material resin can be supplied intermittently by repeatedly stopping / permitting the feeder control. It can be in the state including the voids.
[0019]
According to a second aspect of the present invention, the distance sensor includes a light emitting means, a light receiving means, and a light transmission fiber having a light exit and a light entrance respectively facing a portion of the screw surface corresponding to the exhaust outer cylinder. The feeder control means is configured to compare the received light level received by the light receiving means with a preset threshold value, and to turn on / off the raw material feeder based on the determined result.
[0020]
The resin raw material supply apparatus for a synthetic resin molding machine according to claim 3 further includes an operation panel, and the threshold value can be changed on the operation panel.
[0021]
In the resin raw material supply device for a synthetic resin molding machine according to claim 4, the charge tank is provided with a residual material detection sensor, and when the weighing process of the molding machine is completed, the residual material detection sensor is An alarm means for outputting an alarm when the remaining amount is detected is further provided.
[0022]
The operation method of the resin raw material supply apparatus for a synthetic resin molding machine according to claim 5 is an operation method of the resin raw material supply apparatus having the following configuration.
[0023]
That is, the supply device is installed at a raw material charging port of a heating cylinder of a synthetic resin molding machine composed of a screw and a casing. The raw material charging port surrounds the inner cylindrical portion for raw material charging, the inner cylindrical portion, and gas. The exhaust outer cylinder connected to the suction device is connected continuously, the charge tank for storing the resin raw material, and the resin raw material stored in the charge tank through the raw material charging inner cylinder of the raw material charging port, A raw material feeder that is controlled to be turned on / off to be supplied into the casing, a distance sensor that is provided in the exhaust outer cylinder portion and detects the presence or absence of the raw material on the screw surface near the raw material inlet, and a raw material feeder And a feeder control means for controlling on / off of the apparatus.
[0024]
In the operation method, the charge tank stores a metered resin raw material for one shot to be replenished to the casing during the metering process of the injection molding machine, and the feeder control means outputs a metering start signal. 1 shot stored in the charge tank by performing on / off control of the raw material supplier in accordance with the detection signal of the distance sensor within the period of the measurement process until the measurement completion signal is output. The resin material is divided into the casing and replenished intermittently .
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0026]
FIG. 1 is an overall configuration diagram showing a resin raw material supply system to a synthetic resin molding apparatus in which the present invention is employed. FIG. 2 is a schematic enlarged longitudinal sectional view of a main part of the embodiment in the system.
[0027]
In FIG. 1, 1 is a main hopper for storing synthetic resin pellets as the main raw material of the present system, and 11 is a recycling hopper for crushing and collecting burrs and the like generated from resin molded products for reuse. Are attached with rotary valves 1a and 11a which can adjust the discharge of a predetermined amount of raw material by timer control. Reference numeral 12 denotes a colorant hopper, and each colorant is supplied to the colorant service hopper 13 by a feeder 12 a attached to the lower end of each colorant hopper 12. The service hopper 13 is provided with a load cell 13a for weighing, and a desired amount of colorant is weighed here and fed to the next step.
[0028]
14 is an air transport line, and the resin raw material discharged from each of the hoppers 1, 11, 12... Is air transported along the air transport line 14 and collected by the suction hopper 2. 15 is a suction blower for pneumatic transportation, and 15a is a filter.
[0029]
In the figure, the suction air from the suction blower 15 is discharged to the atmosphere, but the downstream side of the suction blower 15 is connected to the air transport line 14 via a three-way valve and a heat exchanger, and airflow mixing / preliminary heating is performed. It is also possible to construct an air circulation system for temperature. In this way, the resin raw material collected in the suction hopper 2 is preliminarily heated in the suction hopper 2 by contact with heated air. Reference numeral 21 denotes a level sensor that detects whether or not the resin raw material in the suction hopper 2 has reached a predetermined amount.
[0030]
A charge tank 3 is connected to the lower end of the suction hopper 2 via a second damper 31 (upper damper) operated by an air cylinder 31a, and the resin raw material collected in the suction hopper 2 is the damper 31. the by open, one shot from the upper end material inlet 32 is introduced into the blood Yajitanku 3. Reference numeral 33 denotes a level sensor that detects the remaining amount of the resin material in the charge tank 3. The damper 31 is configured to hermetically shut off the charge tank 3 and its upstream supply line.
[0031]
At the lower end of the charge tank 3, a screw feeder (raw material feeder) 4 that is driven to rotate by a variable speed motor 41 is installed. Further, a discharge port 43 that leads to an inner cylinder portion 5 described later of the screw feeder 4 Double cylinders 5 and 6 described later are connected via a damper 42 (lower damper) operated by an air cylinder 42a, and further connected to a raw material inlet 70 of the synthetic resin molding machine 7.
[0032]
The variable speed motor 41 is repeatedly turned on and off to rotate and stop the screw feeder 4 based on a control command of a feeder control means (CPU) 9 described later in FIG. That is, the raw material supply machine 4 is repeatedly controlled to start (on) and stop (off) every rotation according to a detection signal of a distance sensor S described later. Dropped intermittently.
[0033]
As shown in FIG. 2, the synthetic resin molding machine 7 includes a heating cylinder 71 including a screw 71a and its casing 71b, a hydraulic cylinder 72 that moves the screw 71a forward, a motor 73 that rotates the screw 71a, and The heater 74 is provided around the casing 71b, and an injection or extrusion mold 75 is disposed in close contact with the tip nozzle portion 71c of the heating cylinder 71.
[0034]
The resin material P input from the material input port 70 is heated and melted by the heater 74 while being fed in the casing 71b toward the nozzle portion 71c by the rotation of the screw 71a. The molten resin is compressed with high density in the vicinity of the nozzle portion 71c at the tip. Thereafter, the operation of the ram 72 a of the hydraulic cylinder 72 causes the screw 71 a to move to the left in FIGS. 1 and 2, whereby molten resin is injected from the nozzle portion 71 c and injected into the core of the mold 75. After cooling and curing, the mold 75 is removed and the synthetic resin molded product is taken out.
[0035]
The double cylinder is composed of a raw material charging inner cylinder part 5 and an exhaust outer cylinder part 6 surrounding the inner cylinder part 5. The inner cylinder portion 5 is connected to the discharge side of the screw feeder 4 via a damper 42, and the resin raw material discharged from the screw feeder 4 passes through the inner cylinder portion 5 from the raw material inlet 70 to the molding machine. It is put into the heating cylinder 71.
[0036]
The exhaust outer cylinder portion 6 is disposed so as to surround the inner cylinder portion 5, and a lower end opening thereof communicates with the raw material inlet 70. A suction port 61 is provided in the middle of the outer cylinder portion 6, and an exhaust suction blower 8 is connected to the suction port 61 via a pulsation generator 81. The pulsation generator 81 is composed of a valve body that is operated by a continuously rotating motor (not shown). By alternately opening and closing the pipe 80 along with the rotation of the valve body, the pulsation generator 81 gives strength to the suction air flow in the pipe 80. It is intended to pulsate the suction airflow. By the pulsating suction devices 8 and 81, the inside of the heating cylinder 71 of the molding machine is depressurized to about 600 torr. 82 is a filter.
[0037]
Thus, when the upper damper 31 is closed and the lower damper 42 is opened and the screw feeder 4 is operated, the resin raw material P in the charge tank 3 passes through the raw material input port 70 from the inner cylinder portion 5, and the molding machine 7. It is put into the heating cylinder 71. The charged resin material P is sequentially fed to the front side of the casing 71b by the rotation of the screw 71a, and is heated and melted by the heater 74 during this feeding.
[0038]
Since the suction blower 8 is connected to the exhaust outer cylinder portion 6 via the suction port 61, the raw material is charged from the outer cylinder portion 6 when the resin raw material is charged and the casing 71b is fed. The casing 71b is sucked under reduced pressure through the port 70, and the gas generated in the casing 71b is sequentially discharged. At this time, since the damper 31 hermetically shuts off the charge tank 3 and the supply line upstream thereof, there is no leakage at this portion, and vacuum suction is efficiently performed.
[0039]
In the present invention, since the resin raw material is charged into the charge tank 3 for each shot, the inside of the heating cylinder 71 is kept in a state including a gap with a constant hunger rate obtained by experiments or the like. are possible, thereby are that you in the casing 71b to the optimum gas flow conditions as a possible.
[0040]
Furthermore, since the raw material can be intermittently charged by the material detection operation of the distance sensor S described later, the air gap in the casing 71b can be provided uniformly without being biased. It is possible to ensure an optimal void state for gas discharge.
[0041]
Next, an embodiment of the present invention will be described with reference to an operation time chart of FIG. In FIG. 3, as a previous stage, the pneumatic blower suction blower 15 is activated by the detection signal of the level sensor 21 of the suction hopper 2, and the rotary valves 1 a, 11 a and feeders 12 a of the raw material hoppers 1, 11, 12 are appropriately set. In operation, the resin raw material is pneumatically transported and collected in the suction hopper 2. When the level sensor 21 generates a full signal, the suction blower 15 and each feeder are stopped. These operations are performed based on the detection signal of the level sensor 21 independently of the following steps. During this time, the upper damper 31 is closed, and is hermetically shut off from the charge tank 3 and below.
[0042]
At the start of the molding process, the molding machine 7 is in a standby state in which the holding pressure in the previous process is released and the mold is clamped after demolding. In this state, the hydraulic cylinder 72 is unloaded but the ram 72a is In the extended state, the screw 71a is thus waiting in the forward position within the casing 71b. The exhaust suction blower 8 is always turned on, and the charge tank 3 has already been charged with a resin material as will be described later, and the level sensor 33 outputs a full signal. Further, the lower damper 42 is opened.
[0043]
In this state, when a measurement start signal sw1 is issued from the molding machine 7 (t0), the motor 73 of the molding machine 7 is turned on, and the screw 71a starts to rotate in the direction A in FIG.
[0044]
And according to the presence or absence of the raw material on the surface of the screw 71a detected by the distance sensor S, the variable speed motor 41 repeats the start and stop of rotation, and controls the feeder 4 on / off. That is, if the distance sensor S determines that the raw material is present, the supply machine 4 is turned off to stop providing the raw material resin, while if the distance sensor S determines that there is no raw material, the supply machine 4 is turned on and the raw material resin is stopped. Allow supply of resin. In the example of FIG. 2, the distance sensor S is provided on the upstream side (right side of the raw material input port in FIG. 2), but may be provided on the downstream side (left side of the raw material input port).
[0045]
The resin raw material P charged as described above is heated and melted by the heater 74 while being sequentially fed to the front side of the casing 71b of the heating cylinder 71 by the feeding action accompanying the rotation of the screw 71a. The reaction force is applied to the heating cylinder 71 as the molten resin is pumped to the inner side of the casing 71b. At this time, since the hydraulic cylinder 72 is in an unloaded state, the ram 72a is retracted by this reaction force. When the ram 72a is degenerated and a position sensor (not shown) installed at a predetermined position is operated, a measurement completion signal sw2 is transmitted (t2), and based on this, the motor 73 of the molding machine 7 is turned off and supplied soon. The machine 4 also stops.
[0046]
Thereafter, the hydraulic cylinder 72 of the molding machine 7 is operated, and the ram 72 a is expanded and one shot of molten resin staying at the tip of the heating cylinder 71 is injected from the nozzle 71 c and injected into the mold 75. The pressure holding state (the hydraulic cylinder 72 is in the operating state) is maintained for a predetermined time, and then the operation of the hydraulic cylinder 72 is released to bring it into a no-load state before cooling and demolding.
[0047]
When the resin raw material in the charge tank 3 is sequentially discharged by the operation of the supply device 4 and falls below a predetermined level, the level sensor 33 generates an empty signal (raw material request signal). Thereafter, the upper damper 31 is opened, and the resin raw material is charged into the charge tank 3 from the suction hopper 2 by natural dropping. The lower damper 42 is normally opened, but is closed when the upper damper 31 is opened, and the inside of the heating cylinder 71 of the molding machine 7 is maintained in a reduced pressure state.
[0048]
Further, when the level sensor 33 does not emit an empty signal and detects the remaining amount in spite of the measurement completion signal sw2 being transmitted, the molding machine 7 has not been charged with the resin raw material for one shot. And an alarm is output by alarm means (not shown) such as a buzzer.
[0049]
In addition, when the upper damper 31 is in the open state and the resin raw material is being charged into the charge tank 3, the raw material level in the suction hopper 2 may drop, and the level sensor 21 may emit an empty signal (raw material request signal). At this time, the upper damper 31 is closed and the lower damper 42 is opened, and the air transport blower 15 is operated, and the resin raw materials are pneumatically transported to the suction hopper 2 as described above. To be collected. This is repeated until the level sensor 33 of the charge tank 3 generates a full signal, and preparation for the next molding process is made.
[0050]
FIG. 4 shows a control block diagram for executing the above-described operation, and a feeder control means constituted by the CPU 9 or the like executes and controls the above-described operation sequence. The CPU 9 operates the air transport blower 15 in response to the raw material request signal from the level sensor 21, and opens the upper damper 31 in response to the raw material request signal from the level sensor 33, and accordingly instructs the opening / closing of the lower damper 42. Furthermore, the metering start signal sw1 of the molding machine 7 is received, the on / off control of the feeder 4 is repeated according to the detection signal of the distance sensor S, and the intermittent operation of the feeder 4 is stopped in response to the metering completion signal sw2. .
[0051]
In addition, it goes without saying that the CPU 9 also executes operation control of the exhaust suction blower 8, operation control of the feeders 1 a, 11 a, 12 a in the raw material hoppers 1, 11, 12, operation control of the load cell 13 a, and the like. The operation control of the hydraulic cylinder 72 and the motor 73 of the molding machine 7 is performed by a control sequence unique to the molding machine (not shown). In the resin raw material supply system of the present invention, the measurement start signal sw1 and the measurement from the molding machine 7 are measured. The completion signal sw2 is input and the above operation control is performed.
[0052]
FIG. 5 is a diagram showing a basic configuration of the distance sensor S. As shown in FIG.
[0053]
As shown in FIG. 5, the distance sensor S is a reflected light sensor in which a light emitting element S1 and a light receiver S2 including a light receiving element are combined at the tips of optical transmission fibers S3a and S3b led out to the raw material inlet 70. Yes, when the light emitting element S1 is driven to irradiate the screw 71a with light from the outer cylinder part 6 that is provided outside the inner cylinder part 5 provided in the raw material introduction port 70 and communicates with the suction port 61, The reflected light is detected by the light receiver S2, and the light intensity at that time is measured to determine the presence or absence of the raw material on the surface of the screw 71a near the raw material inlet 70, and the feeder control means 9 is a variable speed motor 41 is driven to turn on and off the feeder 4.
[0054]
The intensity of the reflected light detected by the light receiver is determined by comparison with a preset threshold value. If the intensity is smaller than the threshold value, it is determined that there is no material on the surface of the screw 71a of the material insertion port 70, and the threshold value is set. If it exceeds, it is determined that the raw material is present. FIG. 6 shows a graph showing the relationship between the received light intensity and the threshold value.
[0055]
The light from the light emitting element S1 does not have to be continuous irradiation, and may be intermittent irradiation.
[0056]
In this method, since the threshold value can be freely changed, the amount of raw material charged by the feeder 4 can be controlled by adjusting the threshold value, so that it is possible to adjust to the optimum gap state. In addition, it can easily cope with a raw material resin having a different color and light reflectance as compared with the level sensor.
[0057]
In this way, by providing the reflected light type sensor S and determining the presence or absence of the raw material on the surface of the screw 71a while supplying the resin raw material input from the material input port 70 uniformly, the metering process of the molding machine The optimal gap state at the time is ensured.
[0058]
Then, by carrying out the measuring step with the gap of the optimum starvation rate included in the casing 71b, the gas generated in the casing 71b can be sucked and discharged, and as a result, the quality of the molded product can be improved. Furthermore, by keeping the hunger rate constant for each molding, it is possible to stabilize the weighing process and keep the quality of the molded product constant.
[0059]
The distance sensor is not limited to the one using the optical transmission fiber, and may be a laser sensor, an ultrasonic sensor, or the like.
[0060]
Although not shown in the above embodiment diagrams, an operation panel is provided in the vicinity of the synthetic resin molding apparatus, and the threshold for determining the received light intensity level can be changed from this panel. The threshold value can be changed by an operator at the site, thereby enabling fine adjustment of the air gap state.
[0061]
【The invention's effect】
As can be understood from the above description, in the resin raw material supply device for a synthetic resin molding machine according to claim 1 or 5, and the operation method thereof, since the resin raw material for each shot is put into the casing, It is always possible to include a constant starvation rate void in the casing. In addition, since the on / off control of the feeder is performed while determining the presence or absence of the material on the screw surface in the exhaust outer cylinder, the resin material can be intermittently charged into the casing, and the gap in the casing can be made uniform. can do. With the above action, gas suction can be performed smoothly, thereby preventing gas stagnation in the molten resin that causes silver stripes and cavities, etc., and high-quality resin molded products are efficient. Can be manufactured well.
[0062]
According to the second aspect of the present invention, since the distance sensor is a reflected light type sensor, a threshold value can be set, whereby the interval of intermittent charging can be adjusted, and the gap state can be made uniform. Moreover, it can respond easily also to raw material resin from which a color and light reflectance differ.
[0063]
According to the third aspect, since the threshold value can be changed on the operation panel, the interval of the intermittent supply of the raw material can be adjusted by the operator's on-site operation .
[0064]
According to the fourth aspect, since the remaining amount of the charge tank is detected and an alarm is output, it can be confirmed that the charging of the resin raw material for one shot has not been completed at the end of the measurement process .
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram showing a resin raw material supply system to a synthetic resin molding apparatus in which the present invention is employed.
FIG. 2 is a schematic enlarged longitudinal sectional view of a main part in the system.
FIG. 3 is an operation time chart for the embodiment of the present invention.
FIG. 4 is a control block diagram according to the embodiment of the present invention.
FIG. 5 is a diagram showing a basic configuration of a distance sensor.
FIG. 6 is a graph showing the relationship between received light intensity and threshold value.
[Explanation of symbols]
3 Charge tank 31 Second damper (upper damper)
33 Level sensor (residual material detection sensor)
4 Material feeder 41 Variable speed motor 42 Damper (lower damper)
43 Discharge port 5 Raw material charging inner cylinder part 6 Exhaust outer cylinder part 7 Synthetic resin molding machine 70 Raw material charging port 71 Heating cylinder 71a Screw 71b Casing 74 Heating heater 8, 81 Pulsating suction device 9 Feeder control means S Reflected light type Sensor S1 Light emitting element S2 Light receiver S3a, S3b Optical transmission fiber

Claims (5)

A resin raw material supply device installed at a raw material inlet of a heating cylinder of a synthetic resin molding machine comprising a screw and a casing,
The raw material charging port is provided with a raw material charging inner cylinder portion and an exhaust outer cylinder portion surrounding the inner cylindrical portion and connected to a gas suction device.
The supply device is
A charge tank for storing a resin raw material in which the supply amount for one shot to be replenished to the casing during the weighing process of the injection molding machine is pre-weighed;
A raw material feeder that is on / off controlled to supply the resin raw material stored in the charge tank into the casing through the raw material charging inner cylinder portion of the raw material charging port;
A distance sensor provided in the exhaust outer cylinder portion for detecting the presence or absence of the raw material on the screw surface near the raw material inlet,
A feeder control means for controlling on / off of the raw material feeder,
The feeder control means turns on / off the raw material feeder in accordance with the detection signal of the distance sensor within the period of the weighing process after the weighing start signal is outputted and until the weighing completion signal is outputted. A resin raw material supply device for a synthetic resin molding machine configured to control and to intermittently replenish one shot of the resin material stored in the charge tank into the casing by controlling. In claim 1,
The distance sensor
A light emitting means, a light receiving means, and a light transmission fiber facing the light exit and the light entrance respectively in the portion corresponding to the outer cylinder portion for exhaust on the screw surface;
The feeder control means compares the received light intensity of the reflected light received by the light receiving means with a preset threshold value, and controls the raw material feeder on / off based on the determined result. Resin raw material supply equipment for synthetic resin molding machines. In claim 2,
An operation panel is further provided,
In this operation panel, a resin raw material supply device for a synthetic resin molding machine, in which the threshold value can be changed. In claim 1 or 2,
The charge tank is provided with a remaining material detection sensor,
An apparatus for supplying a resin raw material for a synthetic resin molding machine, further comprising an alarm means for outputting an alarm when the remaining material detection sensor detects the remaining amount of the resin raw material when the measuring step of the molding machine is completed. Installed at the raw material inlet of the heating cylinder of a synthetic resin molding machine consisting of a screw and a casing. The raw material inlet encloses the inner cylinder part for raw material introduction and the inner cylinder part, and is connected to a gas suction device. The exhaust outer cylinder is connected continuously,
A charge tank for storing resin raw materials;
A raw material feeder that is on / off controlled to supply the resin raw material stored in the charge tank into the casing through the raw material charging inner cylinder portion of the raw material charging port;
A distance sensor provided in the exhaust outer cylinder portion for detecting the presence or absence of the raw material on the screw surface near the raw material inlet,
An operation method of a resin raw material supply apparatus comprising a supply machine control means for controlling on / off of the raw material supply machine,
In the charge tank, the metered resin raw material for one shot to be replenished to the casing during the weighing process of the injection molding machine is stored,
The feeder control means turns on / off the raw material feeder in accordance with the detection signal of the distance sensor within the period of the weighing process after the weighing start signal is outputted and until the weighing completion signal is outputted. Operation of the resin raw material supply device for a synthetic resin molding machine, wherein the resin material for one shot stored in the charge tank is divided into the casing and replenished intermittently by controlling Method.

Images