JPS6323005A - Method controlling movement quantity of injection device in injection molder - Google Patents

Abstract

PURPOSE:To reduce a cost by detecting movement quantity of a cylinder based on pressure areas of the cylinder and a supply of hydraulic fluid. CONSTITUTION:Respective pressure areas A1, A2 of a cylinder when it is advanced and retracted are set preliminarily by a setting device 12, and output from the setting device 12, a stroke setting device 13 and a flow setting device 10 are inputted into a computing element 15. Movement quantity of an injection device 2 is computed by the computing element 15, and a stroke is controlled. Thus a cost can be reduced because need of using a movement quantity detector to directly detect movement quantity of the injection device 2 when it is advanced and retracted is eliminated.

Description

Detailed Description of the Invention "Industrial Application Field" The present invention provides a method for controlling the amount of movement of the injection device using the movement time of the injection device in controlling the amount of forward and backward movement of the injection device in an injection molding machine. It is about the method.

``Prior Art'' Conventionally, in an injection molding machine, the amount of forward and backward movement of an injection device has been controlled using a limit switch or a value detected by a movement amount detector such as a potentiometer.

"Problems to be Solved by the Invention" Such conventional methods have a drawback in that, for example, if a limit switch is used, remote setting operation is not possible.

Further, a method using a movement amount detector such as a potentiometer allows remote setting operation, but has the disadvantage that the movement amount detector such as a potentiometer is expensive.

"Means for Solving the Problems" The present invention aims to solve these problems. First, the pressure-receiving area A1 of the hydraulic cylinder that drives the injection device when it moves forward is set.

Also, 2 is set to the pressure receiving area during the retreat.

A supply amount Q 1 of hydraulic oil per unit time for forward and backward movement of the injection device and a Q number are set.

Furthermore, the amount of movement S of the injection device is set in advance.

When the injection device moves forward, a calculator calculates the forward speed V of the injection device by dividing the supply ff1Q of hydraulic oil per unit time by the pressure receiving area AL of the hydraulic cylinder when moving forward.

That is, Qx/A,=Ve.

Similarly, when the injection device is retracted, the computer calculates the retraction speed VZ of the injection device by dividing the hydraulic oil supply ffi Q z per unit time by the pressure receiving area A of the hydraulic cylinder during retraction.

That is, Q2'/Ax-V2.

Next, the preset movement amount S of the injection device is changed to the forward speed v1 of the injection device obtained as described above.
Alternatively, the moving times T1 and T2 of the injection device are obtained by dividing by the backward speed VU using a calculator.

That is, S/vl = T L , S/V2
= T2 There is.

The forward or backward movement of the injection device is controlled during these travel times TL and T2.

"Function" In the present invention, the drive for moving the injection device is controlled by the forward or backward travel time T1, TL of the injection device obtained as described above. This is done using the control device's internal timer.

"Embodiment" The drawings showing one embodiment of the apparatus for carrying out the method of the present invention will be described.

1 is a screw cylinder, 2 is an injection device, 3 is a nozzle,
Reference numeral 4 denotes a stationary plate of the injection molding machine, and the drawing shows a state in which the nozzle 3 is retracted from a mold (not shown) attached to the stationary plate 4. 5 is a hydraulic cylinder.

Movement amount S1 In other words, the stroke is the amount by which the injection device 2 is driven backwards and forwards by the hydraulic cylinder 5 as a sequential operation in every cycle during continuous molding, and is also driven sequentially forward and forward, so that the nozzle 3 comes into contact with the mold. At this point, the process moves to the injection operation process.

That is, here, the amount of movement can be controlled without using a position or stroke detector such as a limit switch or potentiometer that directly detects the amount of movement S.

Further, to explain the specific means for detecting this movement amount S, in the case of forward movement of the injection device 2, a command is issued from the sequencer 11 to energize the solenoid valve 6 1ff1llb, and at the same time, a command is sent to the hydraulic cylinder 5. Amplifier 9 of electromagnetic flow valve 7 through flow rate setting device IO that controls the amount of hydraulic oil.
A command is issued to supply Q1 per predetermined unit time.
(The opening degree of the electromagnetic flow valve 7 is controlled.

At this time, the forward speed V1 of the injection device is as follows: V = Q, /A.

It is.

Here, -Ql is the amount of hydraulic oil supplied per unit time when the injection device 2 advances, which is set by the flow rate setting device IO, as described above, and this is the amount of hydraulic oil supplied to the electromagnetic flow valve 7 as described above.
This is due to the opening command.

Further, A1 indicates the hydraulic oil pressure receiving area of the hydraulic cylinder 5 when the injection device 2 moves forward.

The time T for the injection device to move by the amount of movement S (stroke) is T=S/V.

! By substituting the above v1 = Q1/A in Tearari and Kono V1, we get T, =S/V, = SXA, /Q,
' becomes.

That is, the amount of movement S1, the pressure receiving area A1 when the screw cylinder moves forward, and the amount of supply per predetermined unit time Q1
If is known, then by energizing one side of the valve 6, the injection device 2 can move forward by the amount of movement S and achieve its purpose.

To calculate the travel time T1 of the injection device 2, the set value of the flow rate setter 10, the set value A1 of the cylinder surface edge setter 12, and the forward movement amount S of the injection device 2 are set. The value of the stroke setter 16 is transmitted to the computing unit 15, and the computing unit 15 outputs SXA, /Q.

is calculated, and the travel time T of the injection device is calculated.

This calculation result is transmitted to the sequencer 11, and the sequencer 11 controls the solenoid valve 6 for that time according to the value of the movement time TI, thereby achieving the purpose.

In the case of backward control of the injection device 2, each setting value A I , Q l , Vl, etc. in the case of forward movement is changed to the setting value A
2% Q2, V), etc., and the travel time T
, T:2='5XA2/Q.

It can be found as

In the embodiment of the present invention, hydraulic operation is used, but if the injection device 2 is moved forward and backward by an electric motor, an electric motor rotation speed setting device may be used instead of the flow rate setting device IO. (In this case, the moving speed of the injection device 2 is proportional to the rotation speed of the electric motor.) In this case, the driving device for moving the injection device 2 is the electromagnetic flow valve 7, the solenoid valve 6, and the hydraulic cylinder 5. Instead, a driving means such as an electric motor or a ball screw may be used.

``Effects of the Invention'' According to the present invention, unlike in the past, there is no need to provide a movement amount detector that directly detects the amount of forward and backward movement of the injection device 2.
Since the amount of forward and backward movement can be controlled, the cost of control can be reduced by the cost of installing a movement amount detector.

Moreover, the control can be performed in an extremely simple manner.

[Brief explanation of the drawing]

The drawing is a front view of an embodiment of an apparatus for carrying out the method of the present invention. 2. Injection device 5. ,,,,hydraulic cylinder 1
5. ,. Arithmetic unit A , A , Pressure receiving area S, Travel amount T , T , Travel time Q , Q , Supply amount per unit time V , Forward speed V
,,,,,. Reverse speed

Claims (1)

[Claims] The pressure-receiving area when the hydraulic cylinder that drives the injection device moves forward and the pressure-receiving area when it retreats, the amount of hydraulic fluid supplied per unit time for the forward and backward movement of the injection device, and the amount of movement of the injection device are set in advance. When the injection device moves forward,
A calculator calculates the supply amount of hydraulic oil per unit time.
By dividing by the pressure receiving area when the hydraulic cylinder moves forward,
The forward speed of the injection device is determined, and when the injection device is retracted, the retraction speed of the injection device is determined by dividing the supply amount of hydraulic oil per unit time by the pressure-receiving area of the hydraulic cylinder at the time of retraction. The travel time of the injection device is determined by dividing the set travel amount of the injection device by the forward speed or backward speed of the injection device using a calculator, and the forward and backward travel amount of the injection device is controlled using this travel time. A method for controlling the amount of movement of an injection device of an injection molding machine.