JPH04110126A - Speed-commanding device of injection molding machine - Google Patents

Abstract

PURPOSE:To reduce injection time by a method in which when injection speed and the acceleration time and the deceleration time in injection speed- commanding value are inputted, the speed-changing amount in each sampling time is computed, thereby making speed-commanding pattern, and then a device is constructed so that a motor is driven by said pattern. CONSTITUTION:Injection speed, the acceleration time and the deceleration time of injection speed-command and other molding condition are inputted in the man-machine controller(MMC) provided in a device. MPU makes injection speed-commanding pattern on the basis of the molding condition, and sends a speed-command to servomotor through a motor drive controller, thereby advancing a screw forward and backward. Injection speed-command and the true value of injection speed are monitored by a monitor device. When the injection speed and the acceleration time t1 and the deceleration time t3 in the commanding value of said injection speed are inputted through MMC, the speed-changing values DELTAVa1, DELTAValpha in sampling time tau are computed so that the acceleration and the deceleration are finished in each time, whereby speed- commanding pattern is made, and the servomotor is driven by said speed- commanding pattern.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a speed command device for an injection molding machine.

(Prior art) Conventionally, a molding material heated and fluidized in a heating cylinder is injected into a mold under high pressure, cooled and solidified or hardened therein, and then the mold is opened to take out the molded product. In injection molding machines, the screw is moved back and forth in the heating cylinder by driving the motor, but acceleration and deceleration times are set in the injection speed command sent from the motor drive control device to the servo motor. , the actual value follows the command value of the injection speed well.

If a high injection speed is required, the acceleration time is changed depending on the shape of the mold and the characteristics of the resin, and the acceleration/deceleration time is adjusted within a range that does not deteriorate the tracking of the actual injection speed command value. The aim is to shorten the overall injection time.

(Problems to be Solved by the Invention) However, in the speed command device of the conventional injection molding machine described above, the acceleration time and deceleration time cannot be set to different values.

Here, an electric injection molding machine using a servo motor will be explained.

FIG. 5 is a diagram showing an injection speed pattern and a torque pattern in a speed command device of a conventional injection molding machine.

As shown in the figure, at acceleration time t1, if the actual motor required torque (T, +TL), which is the sum of the acceleration torque T1 required for acceleration and the load torque TL, is the maximum torque that the motor can output in the servo system, then time tz
At (h = t+), the actual motor required torque, which is the sum of deceleration torque T6 and load torque TL, is (Ta −
Tt). Therefore, when decelerating, compared to accelerating, (T, +Tt) - (T4-TL) = 2T
There is a torque margin of t, T-=T d. In other words, the torque of the motor cannot be utilized to its fullest extent.

The present invention provides a speed command bag for the above-mentioned conventional injection molding machine! It is an object of the present invention to provide a speed command device for an injection molding machine that can solve the above problems and shorten injection time by utilizing the maximum torque that a motor can produce even during deceleration.

(Means for Solving the Problems) For this purpose, the injection molding machine control device of the present invention includes a monitor device for monitoring the command value and the actual value of the injection speed, the injection speed, and the command value of the injection speed. a man-machine controller for inputting an acceleration time and a deceleration time at a value; and a means for calculating a speed change amount for each sample time based on the input injection speed and the acceleration time and deceleration time at a command value of the injection speed. , a means for creating a speed command pattern from the speed change amount, a means for driving the motor according to the speed command pattern, a means for setting a plurality of injection speed command values, and a separate means for each command value. The vehicle may have a means for manually adjusting the acceleration time and deceleration time.

(Function) According to the present invention, as described above, there is provided a monitor device for monitoring the command value and actual value of the injection speed, and a monitor device for inputting the injection speed and the acceleration time and deceleration time at the command value of the injection speed. Since it has a man-machine controller and a means for calculating the amount of speed change for each sample time based on the input injection speed and the acceleration time and deceleration time at the injection speed command value, the operator can control the man-machine controller. When inputting the injection speed and the acceleration time and deceleration time at the command value of the injection speed through the controller, the speed change amount is set so that the acceleration/deceleration is completed within the acceleration time and deceleration time.

Then, a speed command pattern is created from this speed change amount, and the motor is driven by the speed command pattern.

In addition, by having means for setting multiple injection speed command values and means for inputting separate acceleration and deceleration times for each command value, various command values can be selected as necessary. At the same time, it is possible to select an acceleration/deceleration pattern based on the command value.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic diagram of a speed command device for an injection molding machine according to the present invention.

In the figure, engineering is a monitor device, 2 is an MMC (man-machine controller), and 3 is an MPU (micro process).
ssingUnit), 4 is a motor drive control device,
5 is a speed detector, 6 is a servo motor, 7 is a belt, 8 is a pulley, 9 is a ball screw, and 10 is a screw.

The MMC 2 is used to input the injection speed, acceleration time and deceleration time of the injection speed command, and other molding conditions. -PU 3 monitors the human power of the above molding conditions,
Output according to the sequence. Then, an injection speed command pattern is created based on the molding conditions, and a speed command is given to the servo motor 6 via the motor drive control device 4.

The rotational motion of the servo motor 6 is transmitted to the screw 0 via the heald 7, pulley 8, and ball screw 9, causing the screw 0 to move forward and backward. Further, the configuration is such that the injection speed command and the actual value of the injection speed can be monitored by the monitor device 1.

In the speed command device of the injection molding machine having the above configuration, ? IM
When the injection speed, acceleration time, and deceleration time are input to the MPU 3 from C2, the MPU 3 creates a speed command pattern using the following method.

Fig. 2 is a speed pattern diagram set by the speed command device of the injection molding machine of the present invention, Fig. 2 (A) is a speed pattern diagram during acceleration, and Fig. 2 (B) is a speed pattern diagram during deceleration. be.

First) During acceleration, the IPU 3 increases the speed increment ΔV in one sample as shown in FIG. 2(A).

is determined by the formula △v* − (V / t + ) xτ.

Similarly, during deceleration, as shown in Figure 2 (B), the decrease in speed Δ■ in one sample is calculated by Δva-(-V/1
3) Calculate by the formula of Xτ.

Then, a speed command pattern can be created from the increment Δv during acceleration and the deceleration Δv4 during g speed.

Figure 3 is a diagram showing the injection speed pattern and torque pattern when the followability is poor in the speed command device of the injection molding machine of the present invention, Figure 3 (A) is an injection speed pattern diagram, and Figure 3 (B) is FIG. 3 is a diagram showing a torque pattern.

When actually performing molding, the operator uses the monitor device 1.
The command value and the actual value of the injection speed are compared, and the minimum acceleration time and minimum deceleration time that provide good followability are input to the MPU 3 via the MMC 2.

In this case, the set values of the acceleration time and deceleration time are too small, and the actual values shown by the broken line cannot follow the command values shown by the solid line.

FIG. 4 is a diagram showing an injection speed pattern and a torque pattern when the followability is good in the speed command device of the injection molding machine of the present invention, FIG. 4(A) is an injection speed pattern diagram,
Figure (B) is a diagram showing a torque pattern.

In this case, the set values of the acceleration time and deceleration time are appropriate, and the actual values shown by the broken line follow the command values shown by the solid line.

Therefore, the torque of the servo motor 6 is effectively utilized.

That is, in the case shown in FIG. 3, the acceleration/deceleration time may be lengthened so that the pattern shown in FIG. 4 is obtained.

Note that the present invention is not limited to the above embodiments,
Various modifications are possible based on the spirit of the present invention, and these are not excluded from the scope of the present invention.

(Effects of the Invention) As explained in detail above, according to the present invention, the acceleration time and deceleration time of the injection speed command can be set separately, so it is possible to mainly shorten the deceleration time. .

In addition, since deceleration at the gate portion can be performed quickly, injection can be performed at high speed and high pressure.

Furthermore, since the overall injection time is shortened, the filling of the resin into the mold is also improved.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a speed command device for an injection molding machine of the present invention;
FIG. 2 is a speed pattern diagram set by the speed command device of the injection molding machine of the present invention, FIG. 2(A) is a speed pattern diagram during acceleration, FIG. 2(B) is a speed pattern diagram during deceleration,
Fig. 3 is a diagram showing an injection speed pattern and a torque pattern when the followability is poor in the speed command device of the injection molding machine of the present invention, Fig. 3 (A) is an injection speed pattern diagram,
Figure (B) is a diagram showing a torque pattern, and Figure 4 is a diagram showing an injection speed pattern and a torque pattern when the followability is good in the speed command device of the injection molding machine of the present invention.
FIG. 4A is a diagram showing an injection speed pattern, FIG. 4<8) is a diagram showing a torque pattern, and FIG. 5 is a diagram showing an injection speed pattern and a torque pattern in a speed command device of a conventional injection molding machine. 1...Monitor device, 2...h anus, 3...? IPU
, 4... Control bag for motor drive! , 5... Speed detector, 6... Servo motor, 7... Heald, 8...
Pulley, 9...ball screw, 10...screw. Patent applicant Sumitomo Heavy Industries, Ltd. sub-agent Patent attorney Makoto Kawagoe (1 other person) -] 71 Full value ≠ Ideal value / Kenguhachicho Keiho

Claims (2)

[Claims] (1) (a) A monitor device for monitoring the command value and actual value of the injection speed; (b) A man-machine controller for inputting the injection speed and the acceleration time and deceleration time at the command value of the injection speed. (c) means for calculating the speed change amount for each sample time based on the input injection speed and the acceleration time and deceleration time at the command value of the injection speed; and (d) calculating a speed command pattern from the speed change amount. (e) means for driving a motor according to the speed command pattern. (2) The injection molding machine according to claim 1, further comprising (a) means for setting a plurality of injection speed command values, and (b) means for inputting separate acceleration and deceleration times for each command value. speed control device.