JPH0552248B2 - - Google Patents

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to a plastic molding machine having a mold clamping mechanism and an injection mechanism. This invention relates to an improvement in a control device for a plastic molding machine that allows pressure, speed, etc. during product ejection to be set to arbitrary values in multiple stages.

[Technical background of the invention and its problems]

Conventionally, as an example of multi-stage control of mold opening/closing speed and pressure and injection plunger speed and pressure in a plastic molding machine, there is one in which a plurality of hydraulic manual valves incorporated in a hydraulic circuit are switched.

FIG. 4 shows an example of a hydraulic circuit that enables this type of multi-stage control, in which 1 is an injection plunger, 2a is
~2d is an injection position detection sensor, 3a is a low speed flow control valve, 3b is a medium speed flow control valve, 4, 5, 6, 8, 10 are solenoid valves, 7 is a relief valve, 9a is a low pressure remote control valve , 9b is a medium pressure remote control valve, and 11 is a hydraulic pump.

Therefore, a case will be described in which injection sensors 2d to 2c are used for high speed and high pressure injection, injection sensors 2c to 2b are used for medium speed and high pressure injection, and injection sensors 2b to 2a are used for low speed and medium pressure injection.

First, when the solenoid a of the solenoid valve 6 that performs the injection operation is excited, and the solenoid b of the solenoid valve 8 is excited, high-speed, high-pressure injection is performed. Furthermore, by exciting the solenoid b of the solenoid valve 5, the injection sensors 2c to 2b perform medium-speed and high-pressure injection. Furthermore, when the injection sensors 2b to 2a further energize solenoid b of solenoid valve 4, solenoid a of solenoid valve 8, and solenoid b of solenoid valve 10, low-speed, medium-pressure injection is achieved.

As described above, a large number of valves are provided, and each of them must be operated individually using a push button or the like, which has the drawback that smooth switching is not possible.

Further, as another example of conventional multi-stage control, there is one using electromagnetic valves such as electromagnetic flow control valves and electromagnetic relief valves, as shown in FIGS. 5 and 6.

As shown in Fig. 5, this is equipped with an operation panel 15 equipped with digital switches 16 in a state corresponding to each displacement position, and the speed and pressure at each position are adjusted based on the settings of each digital switch 16. This is a multi-stage control system.

That is, the operation panel 15 displays the speed during the injection operation,
A first setting section 15a that sets the pressure, a second setting section 15b that sets the speed and pressure during the return operation after injection, and a third setting section 15b that sets the speed and pressure during the mold clamping operation.
A setting section 15c, a fourth setting section 15d for setting the speed and pressure during mold opening operation, etc. are provided, and digital switches 16 are provided for each of these setting sections 15a to 15d depending on the number of change stages. The unit of the numerical value of each digital switch 16 is expressed as a total percentage, and the numerical value is set by operating a setting member (not shown) such as a button or a knob provided for each digital switch 16.

In the example shown in Figure 5, the injection speed is 4 steps and the injection pressure is 3 steps.
Can change in stages. Then, as shown in the figure, set the values of the digital switch 16 for setting the injection speed to 80, 50,
40, 20, and the values of the digital switch 16 for setting the injection pressure are set to 90, 50, 10 in sequence. At first, the injection speed is 80% and the pressure is 90%, high speed and high pressure. Then, the speed drops to 50% but the pressure remains the same, then the speed goes to 40% and the pressure goes to 50%, and finally the speed goes down to 20% and the pressure goes to 10%, which is a low speed and low pressure.

Similarly, the speed and pressure during injection return, the speed and pressure during mold clamping, and the speed and pressure during mold opening can also be set.

However, this method requires a large number of dedicated digital switches 16, making the control panel 15 inevitably large and expensive.

In addition, in the conventional electromagnetic valve system, as shown in Fig. 6, the maximum setting value used is different between the mold clamping side and the injection side, so the electromagnetic flow control valve 21
a, 21b and electromagnetic relief valves 22a, 22b
This is a hydraulic circuit that is installed independently on the mold clamping side and the injection side.

In other words, when the maximum hydraulic pressure is 210 kg/cm ² on the mold clamping side and 140 kg/cm ² on the injection molding side, the digital switch displays the setting as a percentage of the maximum value, as shown in Figure 6. Separate electromagnetic valves, that is, electromagnetic flow control valves 21a and 21b and electromagnetic relief valve 22 so that the maximum value can be set in advance.
It was necessary to provide a and 22b.

In Fig. 6, 17 is an injection cylinder, 18 is a mold clamping cylinder, 19 and 20 are solenoid valves, and 2
3 is a hydraulic pump, 24a to 24d are injection position detection sensors, and 25a to 25d are mold clamping position detection sensors.

As described above, conventional control devices employing electromagnetic valves have separate speed setting and pressure setting sections, and have the problem of requiring a large amount of space.

[Purpose of the invention]

The present invention was made based on the above circumstances, and
The object is to provide a compact control device for a plastic molding machine that can extremely easily perform multistage control of speed and pressure during mold opening/closing operations, injection operations, and ejection operations.

[Summary of the invention]

In order to achieve the above object, the present invention provides a variable area display panel that displays variable areas of speed and pressure of mold opening/closing operation, injection operation, and product ejection operation in a plastic molding machine having a mold clamping mechanism and an injection mechanism. , a selection switch for each operation to select mold opening/closing operation, injection operation, or product ejection operation, an operation position setting switch to set the operation position, and a selection switch to select either speed setting or pressure setting. a switch, one setting switch for setting a speed value or a pressure value, and a display device for displaying the set value, and the mold opening/closing operation, injection operation,
By setting the maximum values of speed and pressure for each operation during ejection operation in advance and specifying the ratio using the one setting switch, speed and pressure settings suitable for each operation can be performed. This is what I did.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 1 to 3.

FIG. 1 shows a hydraulic circuit. In the figure, 30 is an injection cylinder of an injection mechanism. This injection cylinder 30 is driven by a two-axis motor 29 via a solenoid valve 31 and an electromagnetic flow control valve 32 for flow rate adjustment in series. Large capacity pump 33 driven by
It is connected to.

Additionally, a relief valve 34 is provided between the electromagnetic flow control valve 32 and the large capacity pump 33.
However, an electromagnetic relief valve 35 is connected in series to the relief valve 34.

On the other hand, a mold clamping cylinder 38 of the mold clamping mechanism is connected to a small capacity pump 36 driven by the other shaft of the two-shaft motor 29 via a solenoid valve 37.

Further, a conduit 39 is connected at one end between the solenoid valve 31 and the electromagnetic flow control valve 32 and at the other end between the solenoid valve 37 and the small capacity pump 36.
An ejecting cylinder 41 of a product ejecting mechanism is connected to a midway portion of this conduit 39 via a solenoid valve 40.

Further, a check valve 42 is provided at one end of the pipe line 39.

In addition, 43a to 43e are injection position detection sensors,
44a to 44d are mold clamping position detection sensors, 45a,
45b is a protrusion position detection sensor.

The control panel of this device has a configuration as shown in FIG.

That is, the upper part of the control panel 60 has a mold opening/closing operation,
A variable area display panel (operating position display monitor) 61 is provided to display variable areas (operating positions) of speed and pressure for injection operation and product ejecting operation, and a variable area display panel (operating position display monitor) 61 is provided in the center. Push button switches 62a, 62b, 6 as selection switches for selecting one of the operations.
2c, push button switches 63a and 63b as selection switches for selecting either pressure setting or speed setting, and a display section 64 for displaying set values.
are arranged. Further, at the bottom, there is a digital switch 65 as an operation position setting switch for setting the operation position, a digital switch 66 as one setting switch for setting the speed value or pressure value, and writing for storing each set value. A switch 67, a confirmation switch 68 consisting of a push button for confirming the set value, and a cancellation switch 69 consisting of a push button for canceling the set value are arranged.

Therefore, in the present invention, the electromagnetic valve includes one electromagnetic flow control valve 32 for flow rate control and one electromagnetic relief valve 35 for pressure control,
The operating pressure and speed of the injection cylinder 30, the clamping cylinder 38, and the ejection cylinder 41 can be controlled via the respective solenoid valves 31, 37, and 40.

Figure 3 shows an electromagnetic flow control valve 32, an electromagnetic relief valve 35, and a control amplifier 70.
This is an explanatory diagram of a control system that can set the maximum speed and pressure for mold clamping, injection _{, and} ejection operations with a set of _. , maximum pressure P _IM , maximum velocity V _EM and maximum pressure P _EM during ejection are individually set. Then, the operation panel 6 shown in FIG.
0, each operating switch 62a, 62b, 6
By selecting one of 2c, the maximum speed value and maximum pressure value of that operation are selected, and when the speed and pressure are set to a certain value with the setting digital switch 66, the operation will be performed at a percentage of the maximum value of that operation. I will do it.

In other words, if the pressure during the mold clamping operation is set to the maximum value,
When setting P _CM = 210Kg/cm ² , inputting the 50% setting value with digital switch 66 automatically
The pressure becomes 105Kg/cm ² .

Further, selection of operation and setting of pressure and speed for this operation are performed by operating various switches on a control panel 60 shown in FIG. That is,
Whether to set the pressure or the speed is selected by pressing either the push button 63a or 63b, which serves as a selection switch, and whether to select mold clamping operation, ejection operation, or injection operation is selected using the operation selection switch. push buttons 62a, 62b,
Select by pressing one of 62c. In addition, variable area display panel (operating position display monitor) 61
By setting the position number in the digital switch 65 and setting the pressure and speed set values in the digital switch 66, multi-stage control of the speed and pressure of each operation can be performed.

For example, when setting the speed setting of the operation position (2) of the mold opening/closing operation to a high speed of "92.8", first press the speed setting button 63b, then set the digital switch 65 for section setting to "2". At the same time, set the digital switch 66 to "92.8".

Write switch 6 for memorizing each setting value
7 and press the confirmation switch 68 to display the display section 64.
The value "92.8" is displayed.

In order to control the speed and pressure at each position of various operations in this way, a control amplifier 70 (see Fig. 3) is used for the electromagnetic flow control valve 32 for flow rate control and the electromagnetic relief valve 35 for pressure control.
This allows commands to be issued using a single setting digital switch 66.

The cancel switch 69 is used to cancel a set value. For example, if you make a mistake during setting and want to cancel the value, press this switch to cancel the set value of the section number that was last set.

If you want to cancel everything, enter section number "1" and press the cancel switch 69, then press section number "2" and press the cancel switch 69.
Press , and perform the following steps to cancel.

In operation, the pressure and speed of all sections for mold clamping, injection, and ejection operations are set in advance and then started.

〔Effect of the invention〕

As explained above, the present invention provides a plastic molding machine having a mold clamping mechanism and an injection mechanism; A selection switch for each operation selects mold opening/closing operation, injection operation, or product ejection operation, an operation position setting switch for setting the operation position, and a selection switch for selecting either speed setting or pressure setting. , a setting switch for setting a speed value or a pressure value, and a display device for displaying the set value, and displays the maximum speed and pressure for each operation during the mold opening/closing operation, injection operation, and ejection operation. By setting the ratio in advance and specifying the ratio using the one setting switch, speed setting and pressure setting suitable for each operation can be performed. Therefore, multistage control of speed and pressure during mold opening/closing operations, injection operations, and ejection operations can be performed extremely easily, and furthermore, it is possible to provide a compact control device for a plastic molding machine.

[Brief explanation of drawings]

Figures 1 to 3 show one embodiment of the present invention, where Figure 1 is a hydraulic circuit diagram, Figure 2 is a plan view of the control panel, and Figure 3 is an explanatory diagram showing a part of the control system. , FIG. 4 is a hydraulic circuit diagram showing a conventional example of the first injection cylinder section employing a manual valve, and FIGS.
The figures show a second conventional example employing an electromagnetic valve, with FIG. 5 being a plan view of the control panel, and FIG. 6 being a hydraulic circuit diagram. 61...Variable area display panel, 62a to 62c...
Selection switch, 63a, 63b...Selection switch, 64...Display section, 65...Operation position setting switch, 66...Speed and pressure value setting switch,
30...Injection cylinder, 38...Mold clamping cylinder,
41...Protruding cylinder.

Claims (1)

[Claims] 1. In a plastic molding machine having a mold clamping mechanism and an injection mechanism, there is a variable area display panel that displays the speed and pressure variable area of the mold opening/closing operation, injection operation, and product ejection operation, and the variable area display panel that displays the variable area of the speed and pressure of the mold opening/closing operation, injection operation, and product ejection operation. A selection switch for each operation to select ejection operation, an operation position setting switch to set the operation position, a selection switch to select either speed setting or pressure setting, and setting the speed value or pressure value. and a display device to display the set values, and the maximum speed and pressure for each operation during the mold opening/closing operation, the injection operation, and the ejection operation are set in advance, and the A control device for a plastic molding machine, characterized in that the speed and pressure settings suitable for each operation can be set by specifying the ratio with one setting switch.