JPS5862029A - Injection and plasticizing apparatus of injection molder - Google Patents

Abstract

PURPOSE:To control precisely the plasticizing, measuring and injection steps with a large plasticizing capacity retained even for molding when the injection amount is small, by changing the injection speed and pressure at an arbitrary position of the injection stroke of a screw. CONSTITUTION:An arithmetic unit 34 calculates the injection amount from the positions of screws 13, 14 detected by potentiometers 19, 20, and a comparison decision apparatus 35 compares it with the value of a setting apparatus 36 in which a required injection amount is set, and judges the injection amount, injection period, tc. of injection and plasticizing apparatuses 11, 12. A signal sending apparatus 37 sends a control signal required for actuating the injection and plasticizing apparatus 11, which acts on timers and others for controlling the opening periods of an electromagnetic proportional flow rate adjusting valve 21, an electromagnetic proportional pressure adjusting valve 23 and a valve 32. A signal sending apparatus 38 sends a control signal required for actuating the injection and plasticizing apparatus 12, which acts on timers and others for controlling the opening periods of an electromagnetic proportional flow rate adjusting valve 22, an electromagnetic proportional pressure adjusting valve 24 and a valve 32.

Description

[Detailed description of the invention] The present invention relates to an injection plasticizing device for an injection molding machine.

When molding products with a small injection amount [(d) The injection stroke of the screw or plunger (hereinafter simply referred to as screw) in the injection plasticizing device must be shortened to maintain plasticization metering accuracy and control accuracy of the injection process. It is difficult to control the Rimi, Tosui, and
This is caused by the injection stroke being completed before the timer, etc. can reach a stable operating position.

Therefore, the injection amount varied from shot to shot, making it impossible to continuously obtain molded products of stable quality. Screw diameter to solve this drawback? There is an injection plasticizing device that increases the injection stroke, but since the screw diameter is small, the plasticizing section force decreases, the plasticizing metering time becomes longer, and the maximum injection amount decreases. There are drawbacks.

The present invention eliminates the above-mentioned drawbacks, provides an injection plasticizing device for an injection molding machine, which has a large plasticizing capacity even for molding with a small injection amount, and is capable of accurately measuring plasticizing and controlling the injection process. ke.

Next, FIG. 1 shows one embodiment of the present invention, an injection plasticizing device that can completely change the injection speed and pressure at any position during the injection stroke of the scree, and seven cases in which there is an alloy phase.
and 12 is an injection plasticizing device, with screws 13 and 14 rotatable by hydraulic motors 15 and 16, respectively;
It is fitted into the injection cylinders 17 and 18 so that it can move forward and backward. Reference numerals 19 and 20 are potentiometers, which are used to adjust the screw IJ as the screws 13 and 14 move forward and backward,
Changes in position are detected as chemical signals. 21
and 22 are electromagnetic proportional flow rate regulating valves that open 1f't! depending on the strength of the applied voltage or other electrical signal; ! 11111
．． , the amount of pressure oil sent to the hydraulic motors 15 and 16? The rotational speed of the screws 13 and 14 is fully controlled. By changing the strength of electric signals such as voltage applied to 23 and 24 by electromagnetic proportional pressure regulating valves, the set pressure in the circuit is completely changed, and the set pressure of the injection cylinders 17 and 18 is changed. It is something to control. 25 is the injection plasticizing device 1
Inlets 26 and 2 connected to the tips of 1 and 12
7 Yoji molten resin? Introducing and merging, - injection holes 2
This is a nozzle designed to emit light from 8. Said nozzle i
The resin passage 29 in open communication with the injection holes 28 and the inlet ports 26 and 27 of °8 is actuated by hydraulic cylinders 30 and 31 by an electromagnetic switching valve (not shown) or the like.
Valves 32 and 33 are provided for opening and closing. 34
The potentiometers 19 and 20 are operated by a computing device.
What is the injection amount that should be injected from the detected positions of screws 13 and 14? It is calculated. 35 compares the value of the setting device 36, in which the injection amount required for molding is predetermined in advance, with the value calculated by the arithmetic device 34 using a comparison/determination device; 1. The injection amount required for injection molding is
1. This is a device that determines which injection amount between 1 and 12 is required per second, and whether the total injection amount of the injection plasticizing devices 11 and 12 is required. 37 to 39 are signal transmitting devices; 37 is a device for transmitting all necessary signals (such as operating the injection plasticizing device lit); Electromagnetic proportional pressure regulating valve 23 and the valve 32 (not shown)
This acts on a timer that controls the opening time of the

38 is a device that sends control signals necessary to operate the injection plasticizing device 12, and a timer that controls the opening time of the electromagnetic proportional flow rate regulating valve 22, the same pressure regulating valve 24, and the valve 33 (not shown). It works. 39, the injection plasticizing apparatuses 11 and 12'ffi are activated simultaneously by a device that transmits a signal to operate the electromagnetic proportional flow regulating valves 21 and 22, the electromagnetic proportional pressure regulating valves 23 and 24, or the opening time of the valves 32 and 33vi. It acts on the timer etc. that controls the sound.

With the structure described above, the drawbacks listed at the beginning have been eliminated, and it has developed a large plasticizing ability even for molding with a small injection amount. Since the pressure can be changed, the valve provided in the nozzle can be opened and closed according to the injection speed and injection amount commensurate with the pressure, allowing accurate plasticization metering and injection process control. In addition, each of the two injection plasticizing machines can change the injection speed and pressure, and various combinations of injection speed and pressure can be made, so it can handle different operating conditions depending on the shape of the molded product or the properties of the resin material. It is possible. Furthermore, if one of the two injection plasticizers is used for filling one harmonic resin while the other one is used for pressure holding, the former can be used to measure plasticization during the pressure holding process of the latter. It can also help shorten the time.

[Brief explanation of drawings]

Claims (1)

[Claims] ], a plurality of injection plasticizing devices having screws or planar jars, and a plurality of injection plasticizing devices connected to the respective tips of the plurality of injection plasticizing devices through an inlet Introducing all the molten resin from the device, merging it together, and injecting it from one injection hole? Injection plasticizing of an injection molding device consisting of pulp nozzles, which are provided in the same number as the injection plasticizing devices between the molten resin inlet of the nozzle and the injection hole, and which selectively open and close the flow of the molten resin. conversion device. 2. The invention is characterized in that the injection speed and pressure of the plurality of injection plasticizing devices each having the screw or plunger assembly can be changed at any position during the injection stroke of the screw or plunger, respectively. An injection plasticizing device for the injection molding machine described above. 3. Injection plasticizing of the injection molding machine according to claims 1 and 2, characterized in that the plurality of injection plasticizing devices having the screws or plunger metals selectively share the load depending on the injection amount. conversion device.