JP5102387B1 - Injection molding machine with synchronous nozzle touch mechanism - Google Patents

Abstract

An injection molding machine having a synchronous nozzle touch mechanism capable of measuring the time required for retreating an injection unit every cycle and completing nozzle touch simultaneously with completion of mold clamping or in accordance with delay time. .
When a sprue break is used, a difference is calculated by subtracting in order to make the mold clamping time and the injection unit advance time the same. In order to make the mold clamping time and the injection unit advance time the same when using the sprue break, the difference is calculated by subtracting the injection unit advance time from the mold clamping time. The n-th shot clamping time (time from the start of mold closing to the completion of clamping) is measured as T, the time from the start of advancement of the injection unit to completion of nozzle touch (injection unit advancement time) is measured as t, The difference is calculated by the time difference α = T−t. The injection unit advance start time (timing) is set based on the time difference α.
[Selection] Figure 2

Description

  The present invention relates to an injection molding machine, and more particularly to an injection molding machine having a synchronous nozzle touch mechanism.

  The injection molding machine has a mold clamping part and an injection part on the machine base, and if the continuous operation is performed with the nozzle touched during molding by the injection molding machine, the heat at the nozzle tip is taken away by the mold. Uses a sprue break function that pulls the nozzle away from the mold after completion. In a conventional injection molding machine, as shown in FIG. 9, a sequential operation is performed to start mold closing and complete mold clamping (step 1) to start nozzle advancement and injection unit advance completion (step 2). Yes. Hereinafter, the sequential operation in this conventional injection molding machine is referred to as Conventional Technology A. In this prior art A, as shown in FIG. 10, the operation is performed in the order of mold closing, mold clamping, nozzle advance, nozzle touch, and injection. When the nozzle touches, the injection is performed without waiting. Although this can be prevented, there arises a problem that the cycle time is extended. The configuration of each reference numeral in FIG. 9 is the same as or similar to the description of the embodiment for carrying out the invention, and thus the description thereof is omitted.

  Therefore, there is a technique for shortening the cycle time by simultaneously performing the mold closing operation and the nozzle advance operation at the start of the cycle. Hereinafter, a technique for simultaneously shortening the cycle time by simultaneously performing the mold closing operation and the nozzle advancing operation at the start of the cycle is referred to as Conventional Technology B. In this prior art B, as shown in FIG. 11, the cycle time can be shortened by performing the simultaneous operation of the mold closing start and the nozzle advance start. However, since the nozzle touch is usually completed prior to the completion of mold clamping, there is a problem that the nozzle touches the standby state and the molten resin at the nozzle tip is hardened. In order to solve this problem, as shown in FIG. 12, in Patent Document 1, before the start of molding, the difference between the advance time of the injection unit and the time from the mold touch to the completion of mold clamping is obtained. A technique is disclosed in which an injection unit is advanced so as to compensate for the difference, and nozzle touch completion and mold clamping completion are performed simultaneously. Hereinafter, this technology is referred to as Conventional Technology C.

Japanese Patent Laid-Open No. 5-147077

  In this prior art C, the advance time of the injection unit is obtained before the start of molding. However, when the operator reduces the amount of nozzle retraction in order to shorten the cycle during the cycle, or conversely, it is drowned. There is a problem that cannot be applied when the amount of retraction of the nozzle is increased in order to take out the resin.

  Therefore, the present invention provides an injection molding machine having a synchronous nozzle touch mechanism capable of measuring the time required for retreating the injection unit every cycle, and performing nozzle touch completion simultaneously with completion of mold clamping or in accordance with delay time. Is to provide.

  The invention according to claim 1 of the present application has a nozzle touch mechanism that moves the injection unit forward and presses the nozzle against the mold, and moves the injection unit backward after the measurement is completed to move the nozzle away from the mold. In the injection molding machine that performs the mold clamping time measurement unit that measures the time from the start of mold closing to the completion of mold clamping, the injection unit retraction time measurement unit that measures the time from the start of retraction of the injection unit to the completion of retraction, The injection unit in the molding cycle immediately before the current molding cycle from the mold clamping time measured by the mold clamping time measuring unit in any molding cycle from the molding start to the molding cycle immediately before the current molding cycle A time difference calculation unit for subtracting the injection unit reverse time measured by the reverse time measurement unit to obtain a time difference between the mold clamping time and the injection unit reverse time; A controller that advances mold injection and nozzle touch simultaneously based on the time difference obtained by the time difference calculator in the current cycle, or advances the injection unit at the time when the nozzle touch is completed after completion of mold clamping. This is an injection molding machine having a synchronized nozzle touch mechanism.

  In the invention according to claim 2, when the time difference obtained by the time difference calculation unit is positive, that is, when the mold clamping time is longer than the injection unit retraction time, the time difference has elapsed after the mold closing starts. The advancement of the injection unit is started from the time point to the time point when the mold clamping is completed, and when the obtained time difference is zero, the mold closing and the advancement of the injection unit are performed simultaneously or from the time point when the mold closing starts to the time point when the mold clamping is completed. When the calculated time difference is negative, that is, when the mold clamping time is shorter than the injection unit retraction time, the injection unit advances from the mold closing start time to the mold clamping completion time. Or start the advancement of the injection unit first and close the mold between the start of advancement of the injection unit and the time when the time difference elapses. An injection molding machine having a synchronous nozzle touch mechanism as set forth in claim 1, characterized in that to start.

  According to the present invention, it is possible to provide an injection molding machine having a synchronous nozzle touch mechanism capable of measuring the time required for retreating the injection unit every cycle and completing the nozzle touch simultaneously with the completion of mold clamping or in accordance with the delay time. .

It is a schematic block diagram of an injection molding machine. It is a figure explaining subtracting and calculating a difference in order to make mold clamping time and injection unit advance time the same at the time of sprue break use. It is a figure explaining that the temperature fall of the front-end | tip of a nozzle can be suppressed to the minimum if completion | finish of mold clamping and completion of advance of an injection unit can be performed simultaneously. It is a figure explaining the molding cycle concerning the present invention. (A) is a time chart regarding the difference between the mold clamping time and the injection unit advance time in the present invention when the time difference is positive, and (b) is the difference between the mold clamp time and the injection unit advance time in the present invention when the time difference is zero. It is a time chart regarding. (C) is a time chart regarding the difference between the mold clamping time and the injection unit advance time in the present invention when the time difference is negative. (D) is a time chart regarding the difference between the mold clamping time and the injection unit advance time in the present invention when the time difference is negative. It is a supplementary explanatory drawing of the time chart which concerns on this invention. It is a flowchart explaining the flow of the injection molding of the 1st shot which concerns on this invention. It is a flowchart explaining the flow of the injection molding of the (n + 1) th shot (1 <= n) which concerns on this invention (the 1). It is a flowchart explaining the flow of the injection molding of the (n + 1) th shot (1 <= n) which concerns on this invention (the 2). It is a figure explaining the machine operation at the time of sprue break use in a prior art. It is a figure explaining the cycle of the prior art A. FIG. It is a figure explaining the cycle of the prior art B. It is a figure explaining the cycle of the prior art C. FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic configuration diagram of an embodiment of an injection molding machine. The injection molding machine M includes a mold clamping part Mc and an injection part Mi on a machine base Mb, and a numerical controller 50 that controls each part of the injection molding machine M is configured as a main part.
The mold clamping portion Mc includes a fixed platen 33, a movable platen 30, and a rear platen 31, and the movable platen 30 is slidably mounted on a tie bar 32 that combines the rear platen 31 and the fixed platen 33, and the movable platen attached to the rear platen 31. It can be moved in the front-rear direction (the injection part Mi side is forward) by the forward-reverse motor M4. The base of the fixed platen 33 is fixed to the machine base Mb, and the fixed mold 40b is fixed to the rear surface. The movable mold 40 a is fixed to the front surface of the movable platen 30. The rear platen 31 is moved forward and backward by the mold clamping position adjusting motor M5, and its position is adjusted.

  The injection part Mi is composed of a screw forward / reverse servomotor M1, a servomotor M2, an extruder base 15 that supports an injection unit Mu that includes a cylinder 1 in which an injection screw 3 is inserted. The description of the support structure such as the screw forward / backward servomotor M1 in the injection unit Mu is omitted. The nozzle 2 at the tip of the cylinder 1 faces a sprue hole (not shown) of a fixed mold 40b attached to the fixed platen 33. A screw 3 is inserted into the cylinder 1. At the time of injection, the nozzle 2 at the tip of the cylinder 1 is pressed against the sprue hole.

  The nozzle touch device Mt included in the injection unit Mi includes a nozzle touch motor M3, a brake (not shown), and a ball screw 14. The ball screw 14 is rotated by the nozzle touch motor M3 and is fixed to the extruder base 15. The rotational movement is converted into a linear movement by a nut (not shown), and the extruder base 15 moves on a rail (not shown) of the machine base Mb in the front-rear direction (the mold clamping part Mc side is forward) with respect to the mold clamping part Mc. . As the extruder base 15 moves forward, the injection unit Mu attached to the extruder base 15 is pushed forward (the mold clamping portion Mc side is forward). The nozzle touch motor M3 is fixed to the machine base Mb by means not shown.

  The numerical control device 50 is a conventionally known numerical control device used for an injection molding machine, and includes an arithmetic device (not shown) for instructing a sequence operation, and an arithmetic device (not shown) for performing judgment and calculation. Manage the operation of the entire molding machine.

  In the present invention, in the injection molding machine as shown in FIG. 1, the time required for retreating the injection unit can be measured every molding cycle, and the nozzle touch can be completed simultaneously with the completion of mold clamping or in accordance with the delay time. . This method considers injection unit reverse time (nozzle reverse time) = injection unit advance time (nozzle advance time) and measures the time difference from the start of mold closing to the completion of mold clamping by measuring the injection unit reverse time of each molding cycle. The nozzle touch is completed at the same time as the completion of mold clamping or in accordance with the delay time. The injection unit retraction time (nozzle retraction time) = injection unit advance time (nozzle advance time) can be considered as the maximum rated rotation speed of the nozzle touch motor M3 in order to speed up one molding cycle. This is because it is driven so as to rotate forward or backward, and the injection unit Mu moves forward and backward.

  FIG. 2 is a diagram for explaining that the difference is calculated by subtracting in order to make the mold clamping time and the injection unit advance time the same when using the sprue break. In order to make the mold clamping completion and injection unit advance completion the same when using the sprue break, the difference is calculated by subtracting the injection unit advance time from the mold clamping time. The time from the start of mold closing to the completion of mold clamping is T, the time from the start of advancement of the injection unit to the completion of nozzle touch (injection unit advancement time) is t, and the time difference α = T−t is calculated. FIG. 3 is a diagram illustrating that the temperature drop at the tip of the nozzle can be minimized if the mold clamping completion and the injection unit advance completion can be performed simultaneously. In this specification, the time required from the start of mold closing to the completion of mold clamping is referred to as mold clamping time.

Next, the molding cycle according to the present invention will be described with reference to FIG.
In the first shot of the molding start, mold closing and injection unit advancement are started simultaneously to generate mold clamping force and complete nozzle touch after mold clamping is completed. In the first shot, the time taken from the start of mold closing to the completion of mold clamping is set in advance. Further, the injection unit advance time is set longer than the time from the start of mold closing to the completion of mold clamping. As a result, it is possible to avoid a state in which the nozzle remains touching the mold before moving to the injection process.

  A mold clamping time, which is a required time from the start of mold closing of the first shot to the completion of mold clamping, may be measured. When the nozzle touch is completed, the process proceeds to an injection process, a pressure holding process, and a cooling process. The metering process is started simultaneously with the cooling process, and when the metering is completed, the injection unit is retracted (nozzle retracting). When the cooling process is completed, one mold cycle is completed by executing the mold opening process and the ejection process. Here, the required time (injection unit retraction time) related to the injection unit retreat (nozzle retreat) is measured.

  In the second shot of the start of molding, the mold closing, mold clamping, and mold clamping are completed, and the process proceeds to the injection process. On the other hand, in the injection unit, the mold clamping time after the start of mold closing and the first shot obtained from the first shot are measured so that the nozzle touch completion time is the same as the mold clamping completion time. After the time of the difference of the injection unit reverse (nozzle reverse) time obtained by the measurement has elapsed, the advance of the injection unit is started. Thereby, in the molding cycle of the second shot, following the injection process, the pressure holding process, the cooling process, the mold opening process, and the ejection process are executed, and one molding cycle is completed. The metering process starts simultaneously with the cooling process, and the injection unit is retracted after the metering process. Note that the mold clamping time (time from mold closing to mold clamping completion) and injection unit retreat time are measured, and the injection unit advance start time (timing to start the injection unit advance) for the third shot of molding is specified. Used to do.

In FIG. 4, the advancement of the injection unit is started with a delay from the start of mold closing. However, depending on the length of the backward movement time of the injection unit, when the mold closing is started after the mold closing start, the mold clamping completion and the nozzle touch end may not be performed at the same time.
Therefore, with reference to FIG. 5, the difference between the mold clamping time from the start of mold closing to the completion of mold clamping and the injection unit advance time from the completion of nozzle touch in the present invention will be described for each case.
FIG. 5A is a time chart regarding the difference between the mold clamping time and the injection unit advance time in the present invention when the time difference is positive. If the mold clamping time is longer than the injection unit advance time, the injection unit starts to advance with a delay of the difference between the mold clamping time and the injection unit advance time. Thereby, completion of mold clamping and completion of nozzle touch can be performed simultaneously.
FIG. 5B is a time chart regarding the difference between the mold clamping time and the injection unit advance time in the present invention when the time difference is zero. When the mold clamping time and the injection unit advance time are the same length, the mold closing start and the injection unit advance are simultaneously performed. In this case, the mold closing and the injection unit advance completion (nozzle touch completion) can be simultaneously performed by simultaneously starting the mold closing and the injection unit advance.
FIG. 5C is a time chart regarding the difference between the mold clamping time and the injection unit advance time in the present invention when the time difference is negative. By starting the mold closing and the injection unit advance at the same time, the injection unit advance completion (nozzle touch completion) is delayed from the completion of mold clamping, and heat is taken away from the nozzle tip before proceeding to the injection process. Can be prevented.
FIG. 5D is a time chart regarding the difference between the mold clamping time and the injection unit advance time in the present invention when the injection unit advance time until the nozzle touch is completed is longer than the mold clamping time. Prior to the start of mold closing, the injection unit starts to advance. Thereby, mold clamping completion and injection unit advance completion (nozzle touch completion) can be made at the same time (same timing).

  FIG. 6 is a supplementary explanatory diagram of the time chart according to the present invention. In FIG. 6, at which point in each molding cycle the advance of the injection unit is started is determined by calculating the injection unit advance time of the current molding cycle from the injection unit advance time until nozzle touch completion obtained in the previous molding cycle. Ask. Even if the retraction distance of the injection unit is changed after executing multiple molding cycles, the injection unit retraction time in the case of changing the retreat distance of the previous molding cycle is changed in the next molding cycle. It can be found on the basis.

FIG. 7 is a flowchart for explaining a molding cycle of the first shot injection molding according to the present invention. Hereinafter, it demonstrates according to each step. The molding cycle of this injection molding corresponds to the first shot in FIG.
[Step SA01] When the mold closing starts, the injection unit starts to advance.
[Step SA02] Measurement of mold clamping time from the start of mold closing is started.
[Step SA03] It is determined whether or not the mold clamping is completed. If the mold clamping is completed, the process proceeds to Step SA04. If the mold clamping is not completed, the process waits until the mold clamping is completed, and then proceeds to Step SA04.
[Step SA04] The measurement of the mold clamping time is completed.
[Step SA05] The clamping time obtained by measurement is T1 (n).
[Step SA06] It is determined whether or not the advance of the injection unit is completed. If the advance is completed, the process proceeds to Step SA07. If the advance is not completed, the process waits for the completion and proceeds to Step SA07.
[Step SA07] The injection process is started, and when the injection process ends, the process proceeds to Step SA08.
[Step SA08] The pressure holding process is started, and when the pressure holding process ends, the process proceeds to step SA09.
[Step SA09] The cooling process is started.
[Step SA10] The measurement process is started simultaneously with the start of the cooling process.
[Step SA11] It is determined whether or not the measurement is completed. When the measurement is completed, the process proceeds to Step SA12. When the measurement is not completed, the process proceeds to Step SA12 after the measurement is completed.
[Step SA12] The injection unit retreat is started.
[Step SA13] Measurement of the injection unit retraction time from the start of retraction of the injection unit is started.
[Step SA14] It is determined whether or not the injection unit has been retracted. If the operation is completed, the process proceeds to Step SA15. If the operation is not completed, the process proceeds to Step SA15 after completion of the operation.
[Step SA15] The injection unit retreat time measurement is terminated.
[Step SA16] Let the measured injection unit retreat time be T2 (n).
[Step SA17] It is determined whether or not the cooling is completed. If the cooling is completed, the process proceeds to Step SA18. If the cooling is not completed, the process proceeds to Step SA18 after the cooling is completed.
[Step SA18] Mold opening is started, and when mold opening is completed, the process proceeds to Step SA19.
[Step SA19] The molded product in the mold is ejected and the molding cycle for the first shot is completed.

FIG. 8 is a flowchart for explaining the flow of injection molding of the (n + 1) th shot (1 ≦ n) according to the present invention. Hereinafter, it demonstrates according to each step. The molding cycle of this injection molding corresponds to the molding cycles after the second shot in FIG.
[Step SB01] It is determined whether or not the value obtained by subtracting the mold clamping time T1 (n) from the injection unit retraction time T2 (n) is positive. If the subtracted value is positive, the process proceeds to Step SB02 and is subtracted. If the value is not positive (that is, 0 or less), the process proceeds to step SB08.
[Step SB02] The injection unit advances for the length of the injection unit reverse time T2 (n) (advance until the nozzle touch confirmation switch is activated).
[Step SB03] A timer is started when the injection unit starts to advance, and the elapsed time from the start of advance of the injection unit is measured.
[Step SB04] It is determined whether or not the time length of the difference obtained by subtracting the mold clamping time T1 (n) from the injection unit retraction time T2 (n) has elapsed. If it has elapsed, the process proceeds to step SB05, and if the difference time has not elapsed, the process proceeds to step SB05 after waiting for the time to elapse.
[Step SB05] The timer started in step SB03 is reset.
[Step SB06] Mold closing starts.
[Step SB07] Measurement of mold clamping time is started, and the process proceeds to Step SB14.
[Step SB08] Mold closing starts.
[Step SB09] Simultaneously with the start of mold closing, measurement of mold clamping time is started, and the process proceeds to Step SB10.
[Step SB10] The timer is started.
[Step SB11] Determine whether or not the length of the difference time obtained by subtracting the injection unit retraction time T2 (n) from the mold clamping time T1 (n) has elapsed (waiting for time has been completed), If the difference time length has elapsed, the process proceeds to step SB12. If the difference time length has not elapsed, the process proceeds to step SB12 after waiting for the difference to elapse.
[Step SB12] The timer is reset.
[Step SB13] The advancement of the injection unit is started for the time of the injection unit reverse time T2 (n) (advance until the nozzle touch confirmation switch is activated).
[Step SB14] It is determined whether or not the mold clamping is completed. If the mold clamping is completed, the process proceeds to Step SB15. If the mold clamping is not completed, the process proceeds to Step SB15 after the mold clamping is completed.
[Step SB15] The measurement of the mold clamping time is completed.
[Step SB16] The clamping time obtained by measurement is T1 (n + 1).
[Step SB17] It is determined whether or not the advancement of the injection unit is completed. If the advancement is completed, the process proceeds to Step SB18. If the advancement of the injection unit is not completed, the process proceeds to Step SB18 after completion of the advancement.
[Step SB18] The injection process is started, and when the injection process ends, the process proceeds to Step SB19.
[Step SB19] The pressure holding process is started, and when the pressure holding process is completed, the process proceeds to Step SB20.
[Step SB20] The cooling process is started.
[Step SB21] The weighing process is started simultaneously with the start of the cooling process.
[Step SB22] It is determined whether or not the measurement is finished. When the measurement is finished, the process proceeds to Step SB23. When the measurement is not finished, the measurement is finished and the process proceeds to Step SB23.
[Step SB23] The injection unit retreat is started.
[Step SB24] Measurement of the injection time backward time is started from the start of the backward injection unit.
[Step SB25] It is determined whether or not the reverse of the injection unit is completed. If the reverse is complete, the process proceeds to Step SB26. If the reverse is not complete, the process proceeds to Step SB26 after completion of the reverse.
[Step SB26] The injection unit retreat time measurement is completed.
[Step SB27] The measured injection unit retraction time is T2 (n + 1).
[Step SB28] It is determined whether or not the cooling is completed. If the cooling is completed, the process proceeds to Step SB29. If the cooling is not completed, the process proceeds to Step SB29 after the cooling is completed.
[Step SB29] The mold opening process is started, and when the mold opening is completed, the process proceeds to Step SB30.
[Step SB30] The molded product in the mold is ejected, and when the ejection is completed, the process proceeds to Step SB31.
[Step SB31] It is determined whether or not the molding is finished. If the molding is not finished, the process proceeds to Step SB32. If the molding is finished, the process is finished.
[Step SB32] n + 1 is set to n, and the clamping time T1 (n + 1) acquired in the current molding cycle is replaced with the clamping time T1 (n) acquired in the previous molding cycle. The acquired injection unit retraction time T2 (n + 1) is replaced with the injection unit retraction time T1 (n + 1) acquired in the previous molding cycle, the process proceeds to step SB01, and the process is continued.

  Here, the above flowchart will be supplementarily described. The injection unit retraction time T1 (n) and the mold clamping time T2 (n) do not need to be measured every shot. For example, the injection unit retraction time T1 (n) can be set every 10 shots. It is possible to respond promptly when there is a change in the reverse distance. In the above flowchart, the operation of the mold clamping unit and the operation of the injection unit are described as one flow. However, the time (timing) of the mold closing start and the injection unit start is based on the mold clamping time and the injection unit retraction time. As described above, the present invention may be described by describing a flowchart for each operation. The completion of the advancement of the injection unit may be determined based on whether or not the time T2 (n) has elapsed. However, the constituent elements of the nozzle touch device Mt and the nozzle touch confirmation switch are provided so that the extruder base 15 can advance the injection unit. The confirmation switch may be activated when the completion position is reached. The nozzle touch can be confirmed by monitoring the operation of the confirmation switch. In this case as well, the injection unit advance start time does not change that the injection unit advance time in the current molding cycle is determined based on the injection unit advance time measured before or before.

  Note that the time from when the time difference described in the claims has passed to the time when mold clamping is completed includes the same time as the time difference has elapsed and also includes the same time as the time when mold clamping is completed. In the case of completion of mold clamping, the injection unit advance time is represented by a broken line in FIG. The same applies to other similar expressions. Also, with this method, the injection unit advance time of the current molding cycle is obtained from the injection unit retract time of the previous molding cycle, so even if the operator changes the retract amount during the molding cycle, the next shot can be handled. Is possible. Further, since the backward movement time of the first shot of molding can be used as a difference, mold clamping completion and nozzle advance completion can be performed from the second shot of molding start. Therefore, the nozzle does not remain in touch with the mold even at the second shot of the start of molding.

M Injection molding machine Mc Mold clamping part Mi Injection part Mt Nozzle touch device Mu Injection unit Mb Machine base M1 Screw servo motor M2 Servo motor M3 Nozzle touch motor M4 Movable platen forward motor M5 Mold clamping position adjustment motor

1 cylinder 2 nozzle 3 screw 4 hopper 5 heat

14 Ball screw 15 Extruder base

30 Movable platen 31 Rear platen 32 Tie bar 33 Fixed platen 34 Crosshead 36 Toggle mechanism 38 Ball screw shaft

40a Movable side mold 40b Fixed side mold

50 Numerical controller

Claims (2)

In an injection molding machine that has a nozzle touch mechanism that moves the injection unit forward and presses the nozzle against the mold, and moves the injection unit backward after the measurement is completed to move the nozzle away from the mold.
A mold clamping time measuring unit that measures the time from the start of mold closing to the completion of mold clamping;
An injection unit retraction time measuring unit that measures the time from the start of retraction of the injection unit to the completion of retraction;
The injection unit in the molding cycle immediately before the current molding cycle from the mold clamping time measured by the mold clamping time measuring unit in any molding cycle from the molding start to the molding cycle immediately before the current molding cycle A time difference calculation unit for subtracting the injection unit reverse time measured by the reverse time measurement unit to obtain a time difference between the mold clamping time and the injection unit reverse time;
A controller that advances mold injection and nozzle touch simultaneously based on the time difference obtained by the time difference calculator in the current cycle, or advances the injection unit at the time when the nozzle touch is completed after completion of mold clamping. An injection molding machine having a synchronized nozzle touch mechanism. The controller is
When the time difference obtained by the time difference calculation unit is positive, that is, when the mold clamping time is longer than the injection unit retraction time, the advancement of the injection unit from the time when the time difference elapses until the mold clamping is completed after the mold closing is started. Start
When the obtained time difference is zero, the mold closing and the advance of the injection unit are started simultaneously or the advance of the injection unit is started from the mold closing start time to the mold clamping completion time,
When the obtained time difference is negative, that is, when the mold clamping time is shorter than the injection unit retraction time, the advancement of the injection unit is started from the mold closing start time to the mold clamping completion time, or the injection unit Start moving forward,
2. The injection molding machine having a synchronous nozzle touch mechanism according to claim 1, wherein mold closing is started between a time point at which a time difference elapses from a time point when the injection unit starts moving forward.