JPH01286814A - Molding device of resin - Google Patents

Abstract

PURPOSE:To improve a quality of a product, by a method wherein a motor turning and driving a screw and a vibration motor are fitted, a molding material is agitated by vibrating the screw, dispersion in a quantity of injecting plastic to a molding tool part is reduced and a quantity of resin is controlled constantly. CONSTITUTION:A resin molding material is supplied within an extruding cylinder 1 through a replenishment instrument 8, sent to the central part of the cylinder 1 with a screw 2, injected within a shot cavity 17 through a nozzle 15 after heating, sent into a mold cavity in succession and molded into a fixed form. A motor 4 turning and driving the screw 2 and a vibration motor 7 are fitted in series and the vibration motor 7 can be fitted to a rotary shaft or a housing of a rotary driving motor 4. With this construction, the motor 4 is vibrated, the screw 2 is caused to resonate, the uncured molding material filled out in a space around the screw 2 becomes a uniform molecule through agitation and accurate amount is injected.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in an apparatus for molding a resin molding material by injection molding.

(Prior art) Thermoplastic or thermosetting resin molding material is supplied into the cylinder from a supply device, sent to a heating section by a material transfer means such as a screw or piston, and heated in the heating section to become plastic. A resin molding apparatus for molding by injecting a molding material into a mold cavity from a nozzle provided at the tip of a cylinder is well known, and the present inventor previously disclosed the method in Japanese Unexamined Patent Application Publication No. 1986-60-
No. 162620 "Forming device" and JP-A-61-18162
In No. 2 "Resin injection molding method and equipment", we proposed a new molding equipment.

However, with conventional resin molding equipment, it is difficult to maintain a constant amount of resin injected from the nozzle into the mold cavity, resulting in an error of about plus or minus 10%, making it difficult to maintain product precision. Met.

(Problems to be Solved by the Invention) An object of the present invention is to improve the quality of products by reducing the variation in the amount of plastic injected into the mold and controlling the amount of resin to a constant level. The objective is to provide a resin molding device that can.

(Means for Solving the Problems and Their Effects) The above-mentioned object of the present invention is to supply the resin molding material into the cylinder from the supply device and transfer it to the heating section by the material transfer means in the first Li +9=. In the resin molding apparatus that molds by injecting the molding material heated in the feeding and heating section into the shot cavity from the tip of the cylinder and injecting it from the shot cavity into the mold cavity, the material transfer means is configured with a screw. This is achieved by a resin molding apparatus in which a vibration motor is attached in series or parallel to the motor that rotationally drives the screw, and the screw is vibrated to agitate the molding material.

The above-mentioned object of the present invention, in its second aspect, is to supply a resin molding material from a material injection cylinder into a shot cavity, send it to a heating section by a material transfer means, and transfer the molding material heated in the heating section to the shot cavity. A resin molding apparatus that performs molding by injecting molding material from a cavity into a mold cavity, the material injection cylinder being arranged at the bottom of the shot cavity to inject molding material into the shot cavity; This is achieved using a resin molding device that has a piston-cylinder mechanism built into it.

According to the first aspect of the present invention, the vibration motor installed in series or parallel with the motor that rotationally drives the screw rotates and generates vibrations, so that the screw vibrates and enhances the mixing effect of the resin. The resin molecules are uniformly stirred and extruded uniformly. In this way, molding can be performed with a more accurate amount of resin than in the past.

According to the second aspect, the material injection cylinder is arranged at the bottom of the shot cavity to inject the molding material into the shot cavity and extrude it with the piston.
The conventional influence of gravity is eliminated and the resin is uniformly stirred.

Further features and advantages of the invention will become apparent from the following description with reference to the accompanying drawings.

(Embodiment) Fig. 1 shows a resin molding apparatus according to a first embodiment of the present invention. In the figure, 1 is a cylinder for extruding resin material, 2 is a screw for material transfer, and 3 is a cylinder mounting Flange, 4 is a motor that rotationally drives the screw, 4A
is a rotary encoder for detecting and controlling the rotation angle and rotation speed of the motor 4 and the screw 2; 5 is a coupling; 6 is an elastic support that supports the motor; 7 is a vibration motor; 8 is a material replenisher; 9 is a supply item. a mounting member; 10 is a column supporting the tip of the cylinder 1; 13 is an inductor consisting of an excitation coil for high-frequency induction heating; 15 is a material extrusion nozzle;
16 is an injection cylinder, 17 is a shot cavity, 18
1 represents a piston slidably housed in a shot cavity 17, and 19 represents a nozzle for injecting material into a mold cavity (not shown).

Based on this configuration, in the resin molding apparatus shown in FIG.
The resin molding material is supplied into the extrusion cylinder 1 from the supply device 8, sent to the heating part, that is, the center part of the cylinder 1 by the screw 2, and after being heated, it is sent from the nozzle 15 at the tip of the cylinder 1 to the shot cavity 17. It is then ejected into a mold cavity and molded into a predetermined shape.

Based on the features of the present invention, a vibration motor 7 is installed in series with the motor 4 that rotationally drives the screw 2, and the vibration motor 7 has, for example, an unbalanced weight attached to its rotating shaft to convert the centrifugal force caused by the rotation into an excitation force. The vibration motor 7 can be attached to the rotating shaft or housing of the rotary drive motor 4, so that the vibration motor 7 can be used as a
vibrates, causing the screw 2 to resonate, and the uncured molding material filled around the screw 2 is stirred to form uniform molecules, allowing for a precise amount to be injected.

The output of a power supply device (not shown) that supplies electric power to the motor 4 is controlled by a control device including a numerical control device (not shown) using a detection signal of the rotary encoder 4A and a readout signal of a preprogrammed program. This makes it possible to control the starting and stopping of the motor 4, as well as its rotation speed, rotation angle, and the like.

In FIG. 1, the vibration motor 7 is arranged behind the rotary drive motor 4, but the vibration motor 7 is directly connected to the screw 2, and the rotary drive motor 4 is connected to the screw 2 via a belt mechanism or a gear mechanism. In this case, both motors may be arranged in parallel.

Further, other types of vibration motors may be used (for example, a mechanism that generates vibration by applying a magnetic field to a giant magnetostrictive material or an electrostrictive material to cause it to expand and contract may also be used).

In addition, multiple temperature detectors and pressure detectors are attached to the cylinder 1 at appropriate intervals to accurately detect the temperature and pressure of the molding material at each position within the cylinder 1, and this information is centrally controlled. It is sent to a computer in the room, where it records and analyzes the temperature distribution and pressure distribution throughout the device as a function of time, predicts the temperature and pressure distribution in the near future,
It is desirable to control the amount of heat supplied to each part based on the predicted data, thereby controlling the amount of injection more precisely.

FIG. 2 shows a resin molding apparatus according to a second embodiment of the present invention, in which a material injection cylinder 42 is disposed at the bottom of a shot cavity 41, and a screw type extrusion pump 43 is provided.
Pressure is applied to the material using the upper shot cavity 4.
It is configured to eject into the interior of Spout port 44
is located directly below the shot cavity 41 having a circular cross section, and its direction is inclined forward at an angle α, for example 30°, with respect to the vertical direction.

The material transfer means attached adjacent to the shot cavity 41 is composed of a piston-cylinder mechanism including a piston 45 and a cylinder 46 that reciprocate in a generally horizontal direction,
The cylinder 46 is caused to reciprocate by feeding fluid 50 into the cylinder 46 from the cylinder 47 and 48.

According to this type of ejection method, compared to the conventional method of letting the resin fall naturally by gravity, it is possible to freely control the supply speed of the resin, and it is also possible to enhance the stirring effect of the material, making it possible to achieve precision It became possible to inject a large amount. According to the experimental results, the variation in the injection amount when the supply device is attached to the top position and allowed to fall naturally is plus or minus 11%.
When the syringe is attached to the side and the spray is ejected horizontally, the variation is about plus or minus 3%, and when the syringe is attached to the bottom and the spray is made to spray upwards, the variation is about plus or minus 1%. found.

3 to 5 show a mold part of a resin molding apparatus according to a third embodiment of the present invention, and FIG. 3 shows a combination of a first mold 61 and a second mold 62. This represents a method of forming a correction reservoir 63 with a small volume, for example, about 1 to 3% of the total volume, on the surface.

FIG. 4 shows a mating mold to be combined with the first mold 71.
This shows a method in which the molding material 70 is injected into a second mold 72 fixed to the tip of a piston 74 and a cylinder wall 73.

In FIG. 5, a mating mold to be combined with a first mold 81 is composed of an outer part 82 and an inner part 83, the outer part 82 is welded to a cylinder wall 84, and the inner part 83 is welded to a piston 8.
5, and a correction reservoir 88 is formed between the mold 81 and the outer portion 82.

In particular, if you use the method shown in Figure 5, which is a combination of Figures 3 and 4, if the amount of resin injected is too large, it will be absorbed by the correction reservoir, and if the amount of resin injected is too small, it will be absorbed by the amount of push of the piston. If the amount of movement of the piston is controlled in this way, a precise amount of resin can be injected by controlling its position. In this way, by using a part of the tip of the piston as a mold, it is possible to prevent heated resin from sticking to the mold, clogging it and making the injection amount inaccurate, resulting in high-quality molding work. becomes possible.

As explained in detail above, according to the resin molding apparatus of the present invention, the variation in the amount of plastic injected into the mold section is reduced, and the quality of the product is improved by precisely controlling the amount of resin. The technological effects are extremely remarkable.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional front view showing a resin molding apparatus according to a first embodiment of the present invention, and FIG. 2 is a front sectional view showing a cylinder portion of a resin molding apparatus according to a second embodiment of the present invention. FIG. 3 is a longitudinal sectional view showing a mold part of a resin molding apparatus according to a third embodiment of the present invention, FIG. 4 is a longitudinal sectional view showing a mold and a piston cylinder, and FIG. 5 is a vertical sectional view showing a mold and a piston cylinder. FIG. Machining... Extrusion cylinder 2... Screw 3...
Flange 4... Drive motor 5... Coupling 6... Elastic support 7... Vibration motor
8... Replenisher 15... Extrusion nozzle 16... Injection cylinder 17... Shot cavity 18... Piston 19... Injection nozzle 41... Shot cavity 42... Injection cylinder 43...・Pump 44... spout 45...
Piston 46...Cylinder Patent applicant Inoue Japanx Research Institute Representative Patent attorney Masataka Ninomiya Figure 1 Figure 2 @ Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] 1. Supplying resin molding material into the cylinder from a supply device, sending it to a heating section by a material transfer means, and injecting the molding material heated in the heating section into the shot cavity from the tip of the cylinder. In a resin molding apparatus that performs molding by injecting from a shot cavity into a mold cavity, the material transfer means is comprised of a screw, and a vibration motor is installed in series or parallel with a motor that rotationally drives the screw, and the material transfer means is configured with a screw. A resin molding device characterized in that the molding material is stirred by vibration. 2. A resin molded by supplying a resin molding material from a material injection cylinder into a shot cavity, sending it to a heating section by a material transfer means, and injecting the molding material heated in the heating section from the shot cavity into a mold cavity. The molding device is characterized in that the material injection cylinder is arranged on the bottom surface of the shot cavity and is configured to inject the molding material into the shot cavity, and a piston cylinder mechanism is built in the shot cavity. Resin molding equipment.