JP4247139B2 - Injection molding machine and control method thereof - Google Patents

Description

  The present invention relates to an injection molding machine and a control method thereof.

  Conventionally, a molding machine, for example, an injection molding machine has an injection device, and a screw is rotatably and reciprocally disposed in a heating cylinder of the injection device, and the screw is rotated by a drive unit, It can be moved forward and backward. Then, during the weighing process, the screw is rotated in the forward direction, the resin as the molding material that has entered the heating cylinder from the hopper is melted and stored in front of the screw head, and during the injection process, the screw is advanced from the injection nozzle. Resin is injected and filled into the cavity space of the mold apparatus.

  By the way, in the injection molding machine, for example, when a disk substrate is molded as a molded product, a fine pattern of a stamper arranged facing the cavity space is transferred to a resin in the cavity space. However, in order to improve the quality of the disk substrate, the track pitch (information recording density) of the fine pattern is set to about 0.7 [μm], so it is necessary to perform transfer with extremely high transfer accuracy.

  Therefore, it is conceivable to increase the temperature of the resin in order to increase the transfer accuracy of the fine pattern. However, as the temperature of the resin increases, the resin staying in the heating cylinder may carbonize or yellow. It becomes easy to burn the resin. When the burned resin is filled in the cavity space, a molding defect occurs.

  Further, when the resin is burnt, carbides adhere not only to the inner peripheral surface of the heating cylinder but also to various parts of the screw. Therefore, the screw is taken out from the heating cylinder to remove the carbide adhering to the inner peripheral surface of the heating cylinder, or a screw assembly including a screw head, a check ring, a seal ring, etc. disposed at the front end of the screw. It is necessary to decompose and remove the carbide adhering to each place, and the work for that is troublesome.

Therefore, for example, a surface treatment for suppressing resin adhesion is applied to a portion where the resin is liable to adhere, such as a screw head, or a gas for preventing oxidation of the resin is injected into the heating cylinder. For example, the resin is prevented from being burned (see, for example, Patent Document 1).
JP 2000-289067 A

  However, in the conventional injection molding machine, if the surface treatment is performed on the portion where the resin is likely to adhere or if gas is injected into the heating cylinder, not only the cost of the injection molding machine increases, but also the resin It is impossible to reliably prevent the occurrence of burning.

  The present invention solves the problems of the conventional injection molding machine, can improve the quality of the molded product, can reduce the cost of the molding machine, and ensures that the molding material is burned. It is an object of the present invention to provide an injection molding machine and a control method thereof that can be prevented.

  For this purpose, in the injection molding machine of the present invention, a cylinder member, an injection member disposed so as to be movable back and forth in the cylinder member, a drive unit for moving the injection member back and forth, and molding in the cylinder member A temperature at which the temperature of the molding material is set while changing the temperature of the molding material between the temperature required for purging and the molding temperature, a heating source for heating the material, a temperature detection unit for detecting the temperature of the molding material Purge processing means for purging each time the change occurs.

  According to the present invention, in an injection molding machine, a cylinder member, an injection member disposed so as to be movable back and forth within the cylinder member, a drive unit for moving the injection member forward and backward, and molding within the cylinder member A temperature at which the temperature of the molding material is set while changing the temperature of the molding material between the temperature required for purging and the molding temperature, a heating source for heating the material, a temperature detection unit for detecting the temperature of the molding material Purge processing means for purging each time the change occurs.

  In this case, while the temperature of the molding material is changed between the purge required temperature and the molding temperature, purge is performed each time the temperature of the molding material changes by the set temperature, and the molding material is discharged. Further, it is possible to reliably prevent the burning of the molding material staying in the cylinder member. Therefore, it is possible to prevent the occurrence of molding defects and improve the quality of the molded product.

  In addition, since it is not necessary to perform surface treatment on the portion where the molding material is likely to adhere or to inject gas into the cylinder member, the cost of the molding machine can be reduced.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In this case, the case where an injection molding machine is used as a molding machine and a disk substrate is molded as a molded product will be described.

  FIG. 1 is a conceptual diagram of an injection apparatus according to the first embodiment of the present invention.

  In the figure, 11 is a heating cylinder as a cylinder member, 12 is a screw as an injection member disposed so as to be rotatable and reciprocating in the heating cylinder 11, and 13 is a front end of the heating cylinder 11 (in the figure). The injection nozzle 16 attached to the left end) is attached to a predetermined position near the rear end (right end in the figure) of the heating cylinder 11, accommodates resin as a molding material, and supplies it into the heating cylinder 11. A nozzle opening is formed in the injection nozzle 13.

  A first heater (not shown) as a first heating source for heating the resin via the heating cylinder 11 is disposed at a predetermined location on the outer periphery of the heating cylinder 11. In this embodiment, in the present embodiment, a temperature sensor 66 as a first temperature detection unit for detecting the temperature of the resin in the heating cylinder 11 is provided at the front portion (left portion in the drawing) of the heating cylinder 11. Arranged. In the present embodiment, one temperature sensor 66 is arranged, but a plurality of temperature sensors can be arranged.

  Similarly, a second heater (not shown) as a second heating source for heating the resin through the injection nozzle 13 is disposed on the outer periphery of the injection nozzle 13. Is provided with a temperature sensor (not shown) as a second temperature detection unit for detecting the temperature of the resin in the injection nozzle 13.

  The screw 12 includes a flight part and a screw assembly disposed at the front end of the flight part. The flight part includes a screw-like flight 23 formed on the main body of the screw 12, that is, the outer peripheral surface of the screw main body, and a spiral groove 24 is formed by the flight 23. The screw assembly includes a seal ring (not shown) attached to the front end of the flight part, a screw head 27 that extends forward (leftward in the figure) through the seal ring, the screw A check ring (not shown) is provided around the head 27 and prevents the resin from flowing back.

  By the way, the rear end of the heating cylinder 11 is attached to a front injection support 31 as a first support member, and a rear injection support 32 as a second support member at a predetermined distance from the front injection support 31. Is disposed. A guide bar 33 is installed between the front injection support 31 and the rear injection support 32, and a pressure plate 34 as a third support member advances and retreats along the guide bar 33 (moves in the horizontal direction in the figure). Arranged freely. The front injection support 31 is fixed to a slide base (not shown) with a bolt (not shown), and is attached to a plasticizing moving device (not shown) via the slide base. The plasticizing moving device includes a support plate that supports the injection device, a rail that is attached to a frame of an injection molding machine and guides the support plate, a plasticizing moving motor as a drive unit for plasticizing movement, and the like. By driving the plasticizing movement motor, the support plate is moved back and forth along the rail, the injection device is moved forward (moved leftward in the figure), and the injection nozzle 13 is brought into contact with a mold device (not shown). The injection nozzle 13 can be moved away from the mold apparatus by moving the injection apparatus backward (moving rightward in the drawing).

  Further, a drive shaft 35 is connected to the rear end of the screw 12, and the drive shaft 35 is rotatably supported by the pressure plate 34 by bearings 36 and 37. A metering motor 41 composed of an electric servo motor is attached to the pressure plate 34 as a metering drive unit, and is composed of pulleys 42 and 43 and a timing belt 44 between the metering motor 41 and the drive shaft 35. A first rotation transmission unit is disposed. Therefore, by driving the metering motor 41, the screw 12 can be rotated in the forward direction or the reverse direction. In the present embodiment, the metering motor 41 including an electric servo motor is used as the metering drive unit. However, a hydraulic motor may be used instead of the electric metering motor 41. it can.

  Further, a ball screw 47 including a ball screw shaft 45 and a ball nut 46 screwed together is disposed behind the pressure plate 34 (rightward in the drawing). The motion direction conversion unit is configured to convert the rotational motion of the ball nut 46 into the straight motion of the ball nut 46. The ball screw shaft 45 constitutes a first conversion element, and the ball nut 46 constitutes a second conversion element. Moreover, it can replace with the said ball screw 47 and can use a roller screw as a moving direction conversion part. The roller screw includes a roller screw shaft as a first conversion element and a roller nut as a second conversion element, and converts the rotational motion of the roller screw shaft into a linear motion of the roller nut.

  The ball screw shaft 45 is rotatably supported by a bearing 48 with respect to the rear injection support 32, and the ball nut 46 includes a plate 51 as a holding member and a load cell 52 as a strain detection unit. To the pressure plate 34.

  Further, an injection motor 53 comprising an electric servo motor as an injection drive unit is attached to the rear injection support 32, and pulleys 54, 55 are disposed between the injection motor 53 and the ball screw shaft 45. And the 2nd rotation transmission part which consists of a timing belt 56 is arrange | positioned. Therefore, by driving the injection motor 53 and rotating the ball screw shaft 45, the ball nut 46 and the pressure plate 34 can be advanced and retracted, and the screw 12 can be advanced and retracted. In the present embodiment, an injection motor 53 including an electric servo motor is used as the injection drive unit. However, an injection cylinder can be used instead of the injection motor 53. .

  In the injection molding machine having the above-described configuration, the molding processing means (not shown) of the control unit 71 performs molding processing and performs molding according to predetermined molding conditions. Therefore, during the weighing process, the weighing processing means of the molding processing means performs the weighing process, and when the weighing motor 41 is driven to rotate the screw 12 in the forward direction, the pellet-shaped resin in the hopper 16 is heated. It enters into the cylinder 11, advances in the groove 24, is melted by the first heater, and is stored in front of the screw head 27. Accordingly, the screw 12 is retracted.

  Subsequently, during the injection process, the injection processing means of the molding processing means performs an injection process, and when the screw 12 is advanced by driving the injection motor 53, the resin stored in front of the screw head 27 is injected. It is injected from the nozzle 13 and filled into the cavity space of the mold apparatus.

  In the mold apparatus, a stamper is disposed so as to face the cavity space, and a fine pattern of the stamper is transferred to the resin filled in the cavity space. Subsequently, a hole is drilled by a cut punch of a mold apparatus to form a disk substrate.

  Incidentally, a setter 72 is connected to the control unit 71, and injection molding is performed according to various molding conditions set in the setter 72. In addition to detecting the load by the load cell 52 and the temperature of the resin by the temperature sensor 66, the rotor of the metering motor 41 detected by a not-shown metering position detector disposed in the metering motor 41 is also shown. , The position of the rotor of the injection motor 53 detected by an injection position detection unit (not shown) disposed in the injection motor 53, and the like are sent to the control unit 71. When the positions of the rotors of the metering motor 41 and the injection motor 53 are sent, a rotational speed detection processing means (not shown) of the control unit 71 performs a rotational speed detection process, and performs measurement based on the position of each rotor. The rotational speeds of the motor 41 and the injection motor 53 are calculated and detected.

  A position detection processing unit (not shown) of the control unit 71 performs position detection processing, and calculates and detects the position of the screw 12, that is, the screw position, based on the position of the rotor of the injection motor 53. Can do. In addition, a position sensor as a position detection unit (not shown) is provided in the injection device, and the screw position can be detected by the sensor output of the position sensor.

  By the way, in order to improve the quality of the disk substrate, the track pitch (information recording density) of the fine pattern is set to about 0.7 [μm], so it is necessary to perform transfer with extremely high transfer accuracy. Therefore, it is conceivable to increase the temperature of the resin in order to increase the transfer accuracy of the fine pattern. However, as the temperature of the resin increases, the resin staying in the heating cylinder may carbonize or yellow. It becomes easy, and it becomes easy to generate | occur | produce a resin, and when the resin which the baking generate | occur | produced is filled in a cavity space, a shaping | molding defect will generate | occur | produce.

  Further, when the resin is burnt, carbide adheres not only to the inner peripheral surface of the heating cylinder 11 but also to various parts of the screw 12. Therefore, it is necessary to take out the screw 12 from the heating cylinder 11 and remove the carbide adhering to the inner peripheral surface of the heating cylinder 11, or to disassemble the screw assembly to remove the carbide adhering to various places. The work for that is troublesome.

  Therefore, in the present embodiment, in a predetermined state where the injection molding machine is stopped from the start of molding to the end of molding, purging is performed according to predetermined conditions to discharge the resin. I have to.

  FIG. 2 is a time chart showing the operation of the injection apparatus according to the first embodiment of the present invention.

  First, when an operator operates an operation unit (not shown) to turn on a start switch of an injection molding machine, a heat insulation processing unit (not shown) of the control unit 71 (FIG. 1) performs a heat insulation process, and the first, The second heater is turned on to heat the resin through the heating cylinder 11 and the injection nozzle 13, and the first and second heaters are set so that the temperature detected by the temperature sensor 66 or the like becomes equal to the set heat retention temperature. Turn on and off.

  Subsequently, when the operator operates the operation unit to start molding and turns on the molding start switch, the first temperature increase processing unit (not shown) of the control unit 71 performs the first temperature increase. The process is started, the first and second heaters are kept on, and the temperature of the resin is increased at the first rate of temperature increase. In the injection molding machine, even if the start switch is turned on and then the molding start switch is turned on, the injection molding machine remains stopped unless the molding process is started.

  When the temperature of the resin becomes equal to the temperature at which purging needs to be performed as the first monitoring temperature (320 [° C.] in this embodiment), that is, the purge required temperature, the first rise The temperature processing means ends the first temperature raising process, and the second temperature raising processing means (not shown) of the control unit 71 starts the second temperature raising process, and the temperature riser preset by the setting device 72 is set. The set temperature is gradually changed according to the temperature pattern, the first and second heaters are turned on / off, and the temperature of the resin is increased at a second temperature increase rate lower than the first temperature increase rate. In the present embodiment, the second temperature increase rate is set lower than the first temperature increase rate, but the first and second temperature increase rates can also be set equal.

  In addition, a first purge processing unit (not shown) of the control unit 71 starts the first purge processing and performs purge intermittently. For this purpose, the first purge processing means starts timing by a timer (not shown) built in the control unit 71 as the first purge processing starts, and drives the plasticizing movement motor. The injection device is retracted, and the injection nozzle 13 is separated from the mold device. The first purge processing means performs a purge every time t1 every time a preset time T1 elapses, and performs metering by driving the metering motor 41 while the purge is being performed. And the injection by driving the injection motor 53 is alternately repeated, the resin in the heating cylinder 11 is agitated (stirred), and discharged intermittently from the injection nozzle 13.

  During this time, the second temperature raising means continues to turn on the first and second heaters, so that the temperature of the resin increases during time T1, but during time t1, purging is performed, Since the resin is repeatedly discharged, the temperature of the resin does not increase and becomes substantially constant.

  In the present embodiment, the time T1 is constant during the first purge process, but the lower the resin temperature, that is, the longer and higher the closer to the purge temperature required temperature, That is, the closer to the molding temperature, the shorter can be achieved. In the present embodiment, the time t1 is constant while the first purge process is being performed. However, the time t1 is shorter as the temperature of the resin is closer to the required purge temperature, and is longer as the temperature is closer to the molding temperature. be able to.

  When the temperature of the resin is equal to a temperature suitable for performing molding (390 [° C.] in the present embodiment) as the second monitoring temperature, that is, equal to the molding temperature, the second temperature rise is performed. The temperature processing means ends the second temperature raising process, and the molding processing means of the control unit 71 starts the molding process and turns on the first and second heaters to keep the resin temperature at the molding temperature.・ Turn it off. Then, the molding processing means drives the plasticizing movement motor to advance the injection device, the injection nozzle 13 is brought into contact with the mold device, the metering processing by the metering processing means, and the injection processing by the injection processing means. I do.

  The purge required temperature and the molding temperature can be appropriately changed by operating the setting device 72 according to the type of resin used.

  By the way, if the molding process is not started immediately after the temperature of the resin reaches the molding temperature, purging can be performed.

  Therefore, a molding standby processing unit (not shown) of the control unit 71 starts a molding standby processing, and the second purge processing unit of the control unit 71 is a second purge process similar to the first purge process. To start. The second purge processing means starts counting by the timer, and performs a purge by time t2 every time a preset time T2 elapses while keeping the injection nozzle 13 away from the mold apparatus. While the purge is being performed, measurement and injection are repeated, the resin in the heating cylinder 11 is stirred, and is intermittently discharged from the injection nozzle 13.

  During this time, the molding standby processing means turns on and off the first and second heaters in order to keep the temperature of the resin at the molding temperature. Therefore, the temperature of the resin does not increase and becomes substantially constant. In the present embodiment, the time T2 is equal to the time T1, and the time t2 is equal to the time t1, but the times T2 and t2 can be arbitrarily set. In the present embodiment, the times T2 and t2 are made equal while the second purge process is being performed.

  When the molding process is started before a preset molding waiting time τ1 (15 [minutes] in the present embodiment) elapses after the second purge process is started, the molding process is started. The standby processing means ends the molding standby processing, the second purge processing means ends the second purge processing, and the molding processing means drives the plasticizing movement motor to advance the injection device. Then, the injection nozzle 13 is brought into contact with the mold apparatus, and the measurement processing by the measurement processing means and the injection processing by the injection processing means are performed.

  Further, when the molding standby time τ1 elapses without the molding process being started, the molding standby processing means ends the molding standby process, and the second purge processing means ends the second purge process. Subsequently, a first temperature-decreasing process unit (not shown) of the control unit 71 performs a first temperature-decreasing process, and gradually changes a set temperature in accordance with a temperature-decreasing pattern set in advance by a setting device 72. The heater No. 2 is turned on / off to lower the resin temperature at the first temperature drop rate.

  Further, a third purge processing means (not shown) of the control unit 71 starts the third purge processing and intermittently purges. For this purpose, the third purge processing means starts timing by the timer with the start of the third purge processing. The third purge processing means performs the purge every time t3 every time the preset time T3 elapses while keeping the injection nozzle 13 away from the mold apparatus, and while the purge is being performed. The measurement and injection are repeated, the resin in the heating cylinder 11 is stirred, and is intermittently discharged from the injection nozzle 13.

  During this time, during the time t3, the purge is performed and the resin is repeatedly discharged, so that the temperature of the resin is lowered.

  When the temperature of the resin reaches the purge required temperature, the first temperature lowering processing means ends the first temperature lowering process, and the second temperature lowering processing means (not shown) of the control unit 71 A temperature lowering process is started, the first and second heaters are turned off, and the temperature of the resin is lowered at a second temperature lowering rate higher than the first temperature lowering rate. In the present embodiment, the second temperature decrease rate is set higher than the first temperature decrease rate, but the first and second temperature decrease rates can also be set equal.

  In the present embodiment, the time T3 is equal to the times T1 and T2, and the time t3 is equal to the times t1 and t2. However, the times T3 and t3 can be arbitrarily set. In the present embodiment, the time T3 is fixed while the third purge process is being performed. However, the time T3 is longer as the temperature of the resin is closer to the purge required temperature and shorter as the temperature is closer to the molding temperature. be able to. The time t3 is constant during the third purge process, but it can be shortened as the temperature of the resin is closer to the purge required temperature and can be longer as the temperature is closer to the molding temperature.

  Subsequently, when the temperature of the resin becomes equal to the heat retention temperature, the heat retention processing means turns on and off the first and second heaters to keep the resin temperature at the heat retention temperature.

  In the present embodiment, in order to perform the purge, the metering and the injection are alternately repeated by the first to third purge processing means, but the screw 12 is held at a predetermined position. By rotating as it is, the resin in the heating cylinder 11 can be stirred and discharged from the injection nozzle 13. In addition, the metering is performed first, and after the screw 12 reaches the backward limit position, the screw 12 is rotated while being held at the backward limit position, thereby stirring the resin in the heating cylinder 11, and It can also be discharged from the injection nozzle 13.

  Since the injection molding machine seems to be stopped while the purge is being performed, the notification processing unit (not shown) of the control unit 71 performs the notification process and is not shown while the purge is being performed. The display unit displays that purging is being performed and notifies the operator. In this case, instead of displaying on the display unit, it is also possible to notify the operator that purging is being performed by a patrol light, a lamp, a buzzer, or the like. Further, the notification process can be performed while the first to third purge processes are being performed, the molding standby process is being performed, and the like.

  The heating cylinder 11, the screw 12, the metering motor 41, the injection motor 53, the temperature sensor 66, the control unit 71, and the like constitute an injection molding machine.

  Thus, even if the temperature of the resin is set high in order to increase the transfer accuracy of the fine pattern, the purge is intermittently performed and the resin is stirred in the heating cylinder 11 and discharged from the injection nozzle 13. Therefore, the resin staying in the heating cylinder 11 is not carbonized or yellowed, and it is possible to reliably prevent the burning. Therefore, it is possible to prevent molding defects from occurring and improve the quality of the disk substrate.

  Further, the screw 12 is taken out from the heating cylinder 11 to remove the carbide adhering to the inner peripheral surface of the heating cylinder 11, or the screw assembly disposed at the front end of the screw 12 is disassembled and adhered to various places. Since it is not necessary to remove the carbide, maintenance and management of the injection device can be simplified.

  Furthermore, since it is not necessary to perform surface treatment on the portion where the resin is likely to adhere or to inject gas into the heating cylinder 11, the cost of the injection molding machine can be reduced.

  Next, a second embodiment of the present invention will be described. In addition, since it has the same structure as 1st Embodiment about an injection device, FIG. 1 is used.

  FIG. 3 is a time chart showing the operation of the injection apparatus according to the second embodiment of the present invention.

  First, when the operator operates the operation section to turn on the start switch of the injection molding machine, the heat retaining means turns on the first and second heaters as the heating source and functions as a cylinder member. The resin as the molding material is heated via the heating cylinder 11 (FIG. 1) and the injection nozzle 13 so that the temperature detected by the temperature sensor 66 or the like as the temperature detection unit becomes equal to the set heat retention temperature. Then, the second heater is turned on / off.

  Subsequently, when the operator operates the operation unit to turn on the molding start switch, the first temperature raising process means starts the first temperature raising process, and the first and second heaters Is kept on and the temperature of the resin is increased at the first rate of temperature increase.

  When the temperature of the resin reaches the purge required temperature as the first monitoring temperature (320 [° C.] in the present embodiment), the first temperature raising means performs the first temperature raising treatment. The second temperature raising process means starts the second temperature raising process, gradually changes the set temperature in accordance with the temperature raising pattern preset in the setting device 72, and the first and second The heater is turned on and off, and the temperature of the resin is increased at a second temperature increase rate lower than the first temperature increase rate. In the present embodiment, the second temperature increase rate is set lower than the first temperature increase rate, but the first and second temperature increase rates can be set equal.

  The first purge processing means starts the first purge processing and intermittently purges. For this purpose, the first purge processing means drives the plasticizing movement motor to retract the injection apparatus, and separates the injection nozzle 13 from the mold apparatus. Then, the first purge processing means reads the temperature of the resin detected by the temperature sensor 66 and performs the purge every time t11 every time the temperature becomes higher by a preset temperature δtm. For this purpose, a plurality of purge temperatures are set by setting the purge required temperature as an initial temperature for each temperature δtm, and purge is performed each time the detected temperature becomes equal to the purge temperature.

  While the purge is being performed, the first purge processing means performs the metering by driving the metering motor 41 as the metering drive unit and the injection motor 53 as the ejection drive unit. The injection by driving is alternately repeated, the resin in the heating cylinder 11 is stirred, and discharged intermittently from the injection nozzle 13.

  During this time, the temperature raising means keeps turning on the first and second heaters, so that the temperature of the resin becomes high except for the time t11, but during the time t11, the purge is performed and the resin is heated. Is repeatedly discharged, the temperature of the resin does not increase and becomes substantially constant.

  In the present embodiment, the time t11 is made constant while the first purge process is being performed. However, the time t11 is shorter as the temperature of the resin is closer to the purge required temperature, and is longer as the temperature is closer to the molding temperature. Can do.

  When the temperature of the resin becomes equal to the molding temperature as the second monitoring temperature (390 [° C.] in the present embodiment), the second temperature raising process means performs the second temperature raising process. The molding processing means starts the molding process and turns on and off the first and second heaters in order to keep the resin temperature at the molding temperature. Then, the molding processing means drives the plasticizing movement motor to advance the injection device, the injection nozzle 13 is brought into contact with the mold device, the metering processing by the metering processing means, and the injection processing by the injection processing means. I do.

  By the way, if the molding process is not started immediately after the temperature of the resin reaches the molding temperature, purging can be performed. For this purpose, the molding standby processing unit starts the molding standby processing, and the second purge processing unit of the control unit 71 starts the second purge processing. Then, the second purge processing means starts counting by the timer, and performs the purge every time t12 every time a preset time T12 elapses while keeping the injection nozzle 13 away from the mold apparatus. While the purge is being performed, measurement and injection are repeated, the resin in the heating cylinder 11 is stirred, and is intermittently discharged from the injection nozzle 13.

  During this time, the molding standby processing means turns on and off the first and second heaters in order to keep the temperature of the resin at the molding temperature. Therefore, the temperature of the resin does not increase and becomes substantially constant. In the present embodiment, the time t12 is equal to the time t11, but the time t12 can be arbitrarily set. In the present embodiment, the times T2 and t12 are made equal while the second purge process is being performed.

  When the molding process is started before a preset molding waiting time τ11 (15 [minutes] in the present embodiment) elapses after the second purge process is started, the molding process is started. The standby processing means ends the molding standby processing, the second purge processing means ends the second purge processing, and the molding processing means drives the plasticizing movement motor to advance the injection device. Then, the injection nozzle 13 is brought into contact with the mold apparatus, and the measurement processing by the measurement processing means and the injection processing by the injection processing means are performed.

  When the molding standby time τ11 elapses without the molding process being started, the molding standby processing unit ends the molding standby process, and the second purge processing unit ends the second purge process. Subsequently, the first temperature decrease processing means of the control unit 71 starts the first temperature decrease process, gradually changes the set temperature according to the temperature decrease pattern preset in the setting device 72, and the first and second The heater No. 2 is turned on / off to lower the resin temperature at the first temperature drop rate.

  In addition, the third purge processing means of the control unit 71 starts the third purge process and performs the purge intermittently. For this purpose, the third purge processing means reads the temperature of the resin detected by the temperature sensor 66, and keeps the injection nozzle 13 away from the mold apparatus, every time the temperature becomes lower by the preset temperature δtm, the time t13. Purge one by one. A plurality of purge temperatures are set by setting the molding temperature as an initial temperature for each temperature δtm, and purge is performed each time the detected temperature and the purge temperature become equal.

  In this case, during the time t13, the purge is performed and the resin is repeatedly discharged, so that the temperature of the resin is lowered.

  When the temperature of the resin reaches the purge required temperature, the first temperature lowering processing unit ends the first temperature lowering processing, and the second temperature lowering processing unit of the control unit 71 performs the second temperature lowering processing. The process is started, the first and second heaters are turned off, and the temperature of the resin is lowered at a second temperature lowering rate higher than the first temperature lowering rate. In the present embodiment, the second temperature decrease rate is set higher than the first temperature decrease rate, but the first and second temperature decrease rates can also be set equal.

  In the present embodiment, the time t13 is equal to the times t11 and t12, but the time t13 can be arbitrarily set. Further, the time t13 is fixed during the third purge process, but it can be shortened as the temperature of the resin is closer to the purge required temperature and longer as it is closer to the molding temperature. The temperature δtm is kept constant during the first and third purge processes, but it can be increased as the temperature of the resin is closer to the purge required temperature and can be decreased as the temperature is closer to the molding temperature. .

  Subsequently, when the temperature of the resin becomes equal to the heat retention temperature, the heat retention processing means turns on and off the first and second heaters to keep the resin temperature at the heat retention temperature.

  In each of the above-described embodiments, when the molding standby times τ1 and τ11 have elapsed without the molding process being started after the second purge process is started, the molding standby process is terminated and the first temperature lowering process is started. However, after the molding process is performed, the operation of the injection molding machine is terminated, and when the injection molding machine is stopped, the first temperature lowering process can be started. .

  In each of the above embodiments, when the molding standby time τ1, τ11 elapses without the molding process being started, the second purge process is ended and the first temperature lowering process is started. The second purge process may be terminated and the first temperature lowering process may be started after purging is performed a set number of times without starting the molding process.

  By the way, if the temperature increase in the injection nozzle 13 is started simultaneously with the start of the temperature increase in the heating cylinder 11, the injection nozzle 13 has a smaller heat capacity than the heating cylinder 11, so that the resin is burned in the injection nozzle 13. Therefore, the timing for starting the temperature rise in the injection nozzle 13 is set so that the timing when the temperature of the resin in the heating cylinder 11 reaches the molding temperature and the timing when the temperature of the resin in the injection nozzle 13 reaches the molding temperature are the same. The timing of starting the temperature rise in the heating cylinder 11 can be delayed.

  In addition, the timing for starting the temperature increase in the injection nozzle 13 and the timing for starting the temperature increase in the heating cylinder 11 are made simultaneous, and the temperature increase rate in the injection nozzle 13 is made lower than the temperature increase rate in the heating cylinder 11. The timing at which the temperature of the resin in the heating cylinder 11 reaches the molding temperature and the timing at which the temperature of the resin in the injection nozzle 13 reaches the molding temperature can be made simultaneous.

  In addition, this invention is not limited to the said embodiment, It can change variously based on the meaning of this invention, and does not exclude them from the scope of the present invention.

It is a conceptual diagram of the injection apparatus in the 1st Embodiment of this invention. It is a time chart which shows operation | movement of the injection device in the 1st Embodiment of this invention. It is a time chart which shows operation | movement of the injection device in the 2nd Embodiment of this invention.

Explanation of symbols

11 Heating cylinder 12 Screw 13 Injection nozzle 41 Weighing motor 53 Injection motor 66 Temperature sensor 71 Control unit

Claims (14)

(A) a cylinder member;
(B) an injection member disposed in the cylinder member so as to freely advance and retract;
(C) a drive unit for advancing and retracting the injection member;
(D) a heating source for heating the molding material in the cylinder member;
(E) a temperature detector for detecting the temperature of the molding material;
(F) during vary between purge required temperature the temperature of the molding material and the molding temperature, characterized in that it has a row Cormorant purging means purging each time changes by temperature at which the temperature is set in the molding material And injection molding machine. 2. The injection molding machine according to claim 1, wherein the purge processing means increases the set temperature as the temperature of the molding material is closer to the purge required temperature. The injection molding machine according to claim 1, wherein the purge processing unit decreases the set temperature as the temperature of the molding material is closer to the molding temperature. (A) a cylinder member;
(B) an injection member disposed in the cylinder member so as to freely advance and retract;
(C) a drive unit for advancing and retracting the injection member;
(D) a heating source for heating the molding material in the cylinder member;
(E) a temperature detector for detecting the temperature of the molding material;
(F) having a purge processing means for purging each time set according to the temperature of the molding material while the temperature of the molding material is changed between the purge required temperature and the molding temperature. Characteristic injection molding machine. 5. The injection molding machine according to claim 4, wherein the purge processing means lengthens the set time as the temperature of the molding material is closer to the purge required temperature. The injection molding machine according to claim 4, wherein the purge processing unit shortens the set time as the temperature of the molding material is closer to the molding temperature. The injection molding machine according to any one of claims 1 to 6, wherein the purge processing unit performs the purge while the temperature raising process is performed to change the temperature of the molding material from the purge required temperature to the molding temperature . Pre Symbol purging means, an injection molding machine according to any one of claims 1 to 6 for purging while cooling process to the temperature of the molding material from the molding temperature to purge required temperature is being performed. The injection molding machine according to any one of claims 1 to 8, wherein the purge processing unit shortens the time for purging as the temperature of the molding material is closer to the purge required temperature. The injection molding machine according to any one of claims 1 to 8, wherein the purge processing means lengthens the purge time as the temperature of the molding material is closer to the molding temperature. The injection molding machine according to any one of claims 1 to 10 , further comprising notification processing means for notifying an operator that purging is being performed while the purging is being performed. (A) having an injection nozzle attached to the front end of the cylinder member;
(B) The injection molding machine according to any one of claims 1 to 11 , wherein the temperature rise start or the temperature rise speed is set differently between the cylinder member and the injection nozzle. Cylinder member, injection member disposed so as to be movable back and forth in the cylinder member, a drive unit for moving the injection member forward and backward, a heating source for heating the molding material in the cylinder member, and detecting the temperature of the molding material In a method for controlling an injection molding machine having a temperature detecting unit,
Between vary between the temperature of the molding material as purge required temperature and the molding temperature, the control method of an injection molding machine, characterized in that intends rows purge every time changes by temperature at which the temperature is set in the molding material. Cylinder member, injection member disposed so as to be movable back and forth in the cylinder member, a drive unit for moving the injection member forward and backward, a heating source for heating the molding material in the cylinder member, and detecting the temperature of the molding material In a method for controlling an injection molding machine having a temperature detecting unit,
A control method for an injection molding machine, wherein purging is performed every time set according to the temperature of the molding material while the temperature of the molding material is changed between the purge required temperature and the molding temperature. .

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