JP3326049B2 - Thermosetting resin injection equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermosetting resin injection device, and more particularly to an injection device capable of efficiently releasing gas in a raw material and reducing variations in injection amount. Note that the thermosetting resin injection device of the present invention is used for molding rubber in addition to the thermosetting resin.

[0002]

2. Description of the Related Art In a conventional thermosetting resin injection apparatus, a resin material is introduced into a heating cylinder from a hopper provided in the heating cylinder, and the resin material is heated by a heating means such as a heater provided in the heating cylinder. While heating and plasticizing, it is sent to the tip of the heating cylinder by a screw in the heating cylinder, and finally the plastic material is injected from the tip of the heating cylinder.

[0003] By the way, a thermosetting resin raw material usually generates a gas at the time of its plasticization. Therefore, in order to obtain a good molded product, it is necessary to inject the gas after releasing the gas. However, in a conventional thermosetting resin injection device, gas venting means is not specially provided, and the gas generated in the heating cylinder has a narrow gap between the inner peripheral surface of the heating cylinder and the outer peripheral surface of the screw. It only escaped behind the heating cylinder. For this reason, sufficient degassing could not be performed, and most of the gas was injected together with the plastic raw material while being confined in the plastic raw material.

Further, the injection device for a thermosetting resin differs from the injection device for a thermoplastic resin in that a check valve cannot be provided at the tip of the screw. This is because, once the thermosetting resin material is plasticized by heating, once it cures with the passage of time, it does not plasticize again even if it is heated again. When the resin raw material stays, the screw may harden as it is and the screw may not be used again.

However, the check valve is required to prevent the raw material from flowing back through a gap existing between the screw groove on the outer peripheral surface of the screw and the inner peripheral surface of the heating cylinder during injection. Therefore, in a conventional thermosetting resin injection device without a check valve, the backflow is likely to occur at the time of injection, and the injection amount changes for each shot, or the injection pressure is not sufficiently transmitted to the mold, and molding failure occurs. There is a problem that easily occurs.

In recent years, an injection device shown in FIG. 7 has been proposed as an injection device for escaping gas in a resin raw material (Japanese Utility Model Application Publication No.
No. 49864). This injection device connects a decompression chamber 71, which is larger than the diameter of the plasticizing heating cylinder 70, to the distal end of the plasticizing heating cylinder 70 at a right angle to the plasticizing heating cylinder 70. A degassing through-hole 72 is formed in the wall surface of the decompression chamber 71 opposite to the above, and a vacuum device (not shown) is connected to the degassing through-hole 72. Then, the pressure in the decompression chamber 71 is reduced by a vacuum device, and a plastic raw material is sent out from the tip of the plasticization heating cylinder 70 into the decompression chamber 71 by a screw 73 in the plasticization heating cylinder 70. After the deaeration, the injection plunger 74 in the decompression chamber 71 is advanced to eject from the front end of the decompression chamber 71. Reference numeral 75 is a hopper, 76 is a screw driving device, 77
Is an injection plunger driving device, and M is a resin raw material.

[0007] However, the injection device shown in FIG. 7 requires large-scale equipment such as a vacuum device, and is directly sent out of the plasticizing heating cylinder to the degassing chamber and is injected therefrom. (Melting), impurities and the like generated from the resin material easily remain in the degassing chamber, and it is not easy to remove the residue. Further, since the degassing chamber and the plasticizing heating cylinder are arranged at right angles, there is a problem that the injection device itself becomes large.

[0008]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of the above points, and it is possible to sufficiently release gas generated during plasticization of a thermosetting resin material from the plastic material, and An object of the present invention is to provide an injection device for a thermosetting resin that can be injected without causing a backflow of a plastic raw material.

[0009]

According to the present invention, a feed screw which is fed from the tip of the plasticizing measuring cylinder by a feed screw in the plasticizing measuring cylinder and supplied to the plunger cylinder is injected from the plunger cylinder by advancement of the plunger. A thermosetting resin injection device, wherein a raw material transfer member having a shutter plate formed on the outer surface of a raw material transfer cylinder having an inner diameter larger than the inner diameter of the plasticizing and measuring cylinder, When feeding the raw material, the raw material transfer cylinder is positioned in communication with the tip of the plasticizing and measuring cylinder. On the other hand, at the time of plasticizing and measuring, the shutter plate closes the plasticizing and measuring cylinder and the raw material transfer cylinder is connected to the plunger. Move between the tip of the plasticizing measuring cylinder and the plunger cylinder so that it is located in communication with the cylinder. Characterized by providing freely.

[0010]

According to the thermosetting resin injection device of the present invention, the feedstock is fed by the feed screw to the tip of the plasticizing measuring cylinder, that is, the plastic raw material after the measurement is completed is
As the feed screw advances, the feed screw is fed into the raw material transfer cylinder located at the tip of the plasticizing measuring cylinder, and is accommodated in the raw material transfer cylinder. At this time, since the inner diameter of the raw material transfer cylinder is larger than the inner diameter of the plasticizing measuring cylinder, the surface area of the plastic raw material increases as soon as the plastic raw material is sent from the tip of the plasticizing measuring cylinder into the raw material transfer cylinder, and the pressure is reduced. State. Therefore, gas generated from the raw material during the plasticization and confined in the plastic raw material as it is is released from the surface of the plastic raw material, and degassing is performed.

Next, the raw material transfer member moves, and the raw material transfer cylinder moves to the position of the plunger cylinder together with the raw material therein. Then, the plunger moves forward and ejects the raw material in the raw material transfer cylinder from the tip of the plunger cylinder. At this time, the plunger is used only for injection, so that plasticization and measurement of the raw material are not performed, and there is no need to provide a screw groove on the outer peripheral surface of the plunger. Therefore, there is no gap between the outer peripheral surface of the plunger and the inner peripheral surface of the plunger cylinder due to the screw groove, and it is possible to prevent the raw material from flowing backward during injection.

Moreover, since the plasticized raw material is once stored in the raw material transfer cylinder portion and then transferred to the plunger cylinder as described above, impurities and the like appearing on the raw material surface during plasticization and degassing are reduced. It remains in the transfer cylinder and moves less to the plunger cylinder. Therefore, the residue can be removed by cleaning the raw material transfer cylinder, and the maintenance is simple. In addition, since a large and expensive device such as a vacuum suction device or the like is not required for degassing, the entire injection device is inexpensive and compact.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a cross-sectional view showing a plasticizing and measuring state of an injection device according to an embodiment of the present invention, FIG. 2 is a cross-sectional view showing a raw material delivery state in the same embodiment, and FIG. 3 is a raw material transfer state in the same embodiment. FIG. 4 is a sectional view showing an injection state in the embodiment, FIG. 5 is a perspective view showing an example of a raw material transfer member, and FIG. 6 is a sectional view showing a main part of an injection apparatus according to another embodiment of the present invention. is there.

The injection device 10 of the present invention shown in FIGS. 1 to 4 has a plasticizing measuring cylinder 20 having a feed screw 25 therein and an plunger cylinder 30 having a plunger 35 provided below and substantially parallel to each other. Have been. The plasticizing and measuring cylinder 20 is formed of a cylindrical body having an opening 21 for feeding the raw material at the tip thereof,
A jacket for distributing the temperature control medium is provided on the outer periphery. A hopper 23 for charging raw materials is attached to the rear of the plasticizing and measuring cylinder 20.

The feed screw 25 feeds a predetermined amount of the thermosetting resin raw material M introduced from the raw material charging hopper 23 to the rear end of the plasticizing and measuring cylinder 20 while kneading and plasticizing the raw material. The feed screw 25 is retracted by that amount to measure the plastic raw material M1 and to feed the plastic raw material M1 to the raw material transfer cylinder 45 of the raw material transfer member 40 described later. The feed screw 25 is inserted into the plasticizing and measuring cylinder 20 so as to be rotatable and forward / backward by a screw driving device 26 provided at a rear portion thereof.

The plunger cylinder 30 injects, by means of a plunger 35, a plastic raw material M 1, which is plasticized in the plasticizing measuring cylinder 20 and accommodated and transferred in a raw material transfer cylinder portion 45 of a raw material transfer member 40 described later. It is for doing. Further, in this embodiment, a heating means 31 composed of a jacket for distributing a temperature control medium is provided on the outer periphery of the plunger cylinder 30 in order to maintain the plastic state of the plastic raw material M1. Further, the tip of the plunger cylinder 30 is a nozzle 32 connected to a mold (not shown).

The plunger 35 is for injecting the plastic raw material M1 transferred into the plunger cylinder 30 from a nozzle 32 at the tip of the plunger cylinder 30 into a mold. The plunger cylinder 30 is moved forward and backward by the moving device 39. The outer diameter of the plunger 35 in the vicinity of the tip is substantially equal to the inner diameter of the plunger cylinder 30, thereby preventing backflow during injection.

Between the tip of the plasticizing measuring cylinder 20 and the plunger cylinder 30, there is provided a raw material transfer member 40 which moves between the two cylinders 20, 30. The raw material transfer member 40 of this embodiment is configured to slide up and down by a raw material transfer member moving device 46 provided on the upper part thereof. Further, in this example, a cylinder device known as the moving device 46 is mounted in a suspended state on the plate-shaped body 33 erected on the upper surface of the peripheral wall of the plunger cylinder 30, and the lower end of the operating rod 47 is attached to the raw material. It is fixed to the transfer member 40.

The raw material transfer member 40 has a shutter plate 4 of a size to close the opening 21 at the tip of the plasticizing measuring cylinder 20, as can be clearly understood from FIG.
1 and a raw material transfer cylinder 45 provided at the lower end of one surface thereof
And

The shutter plate 41 closes the opening 21 at the end of the plasticizing and measuring cylinder 20 during the plasticizing and measuring step described later and opens it during the raw material transfer step. It is arranged to be in sliding contact with. Note that the shutter plate 41 of this embodiment is
A hole is formed in a portion where the raw material transfer cylinder 45 is provided so that the raw material transfer cylinder 45 is not closed.

On the other hand, the raw material transfer cylinder portion 45 accommodates the plastic raw material M1 extruded from the tip of the plasticization measuring cylinder 20 during the raw material transfer step, and after the gas is released from the plastic raw material M1, the plastic raw material M1 is released. The raw material is transferred to the plunger cylinder 30. The raw material transfer cylinder portion 45 has an inner diameter larger than the inner diameter of the plasticizing and measuring cylinder 20 and the plunger cylinder 3
It is made equal to the inner diameter of 0, and is moved between the tip of the plasticizing measuring cylinder 20 and the plunger cylinder 30 by the movement of the raw material transfer member 40. It is preferable that the inner volume of the raw material transfer cylinder portion 45 be larger than the volume of the plastic raw material sent to the tip of the plasticizing and measuring cylinder 20 in the plasticizing and measuring step. In addition, this material transfer cylinder 45
The end surface 46 on the side opposite to the shutter plate 41 slides on the surface of the plate-shaped body 33 erected on the upper surface of the peripheral wall of the plunger cylinder 30. This prevents the plastic raw material from leaking out of the raw material transfer cylinder 45 during the raw material transfer step.

The thermosetting resin injection device 10 thus configured performs the plasticization measurement step, the raw material transfer step, and the injection step as follows. First, in the plasticizing and measuring step, as shown in FIG. 1, the shutter plate 41 of the raw material transfer member 40 is positioned at the tip of the plasticizing and measuring cylinder 20 and closes the resin raw material delivery opening 21. At this time, the raw material transfer cylinder 45 of the raw material transfer member 40 is
It is located at.

Then, the thermosetting resin material M in the material input hopper 23 is rotated by the rotation of the feed screw 25,
It is sent to the tip of the plasticizing measuring cylinder 20 while being kneaded. At that time, the raw material M is heated by frictional heat due to kneading and heat supplied from the heating means 22 on the outer periphery of the plasticizing and measuring cylinder 20, and is sequentially sent to the tip of the plasticizing and measuring cylinder 20 as a plastic raw material M1. During this plasticization, a decomposition gas or the like is generated from the raw material M. A part of the generated gas passes through the gap between the inner peripheral surface of the plasticizing and measuring cylinder 20 and the outer peripheral surface of the feed screw 25, and
Although escaping to the rear, most of the gas is trapped in the plastic raw material M1 and sent to the tip of the plasticizing measuring cylinder 20 together with the plastic raw material M1.

After the plasticized raw material M1 is sent to the tip of the plasticizing and measuring cylinder 20 by a predetermined amount by the rotation of the feed screw 25, that is, after the plasticized raw material M1 is measured, a raw material transfer step is performed. In the raw material transfer step, first, as shown in FIG. 2, the raw material transfer member 40 is raised by the operation of the raw material transfer member moving device 46, and the raw material transfer cylinder 45 is moved to the tip of the plasticizing and measuring cylinder 20 to cause the plasticization. It communicates with the chemical weighing cylinder 20 to open the resin raw material delivery opening 21.

Then, the feed screw 25 advances, and the plastic material M1 at the tip of the plasticizing and measuring cylinder 20 is removed.
The raw material is sent out into the raw material transfer cylinder 45 having an inner diameter larger than the inner diameter of the plasticizing and measuring cylinder 20, and is accommodated in the raw material transfer cylinder 45. At that time, the plastic raw material M1 is sent out to the raw material transfer cylinder 45, and at the same time, the surface area increases and the pressure is reduced.
The gas trapped inside the plastic raw material M1 until then escapes from the surface of the plastic raw material M1 to the outside, and becomes the degassed plastic raw material M2.

After the plastic raw material M1 is sent out to the raw material transfer cylinder portion 45, the operating rod 47 of the raw material transfer member moving device 46 is extended, and the raw material transfer member 40 is lowered. Then, as shown in FIG. 3, the raw material transfer cylinder portion 45 moves to the position of the plunger cylinder 30 together with the degassed plastic raw material M2 housed therein, and the plunger cylinder 3
The plastic raw material M2 is transferred to the inside of the tube. On the other hand, the opening 21 for feeding the resin raw material at the tip of the plasticizing measuring cylinder 20
Is closed by the shutter plate 41. In addition,
In the raw material transfer step, the plunger 3 is moved so that the lowering of the raw material transfer cylinder 45 is not hindered by the plunger 35.
Reference numeral 5 is a retreat position, and the raw material transfer cylinder 45 moves forward of the plunger 35 together with the plastic raw material M2.

Subsequently, an injection step shown in FIG. 4 is performed. In this injection step, the plunger 35 is
0, and the plastic raw material M2 in the raw material transfer cylinder 45 is transferred to the plunger cylinder 30.
Inject from the nozzle 32 at the tip. At that time, plunger 3
5 has no screw groove, and no gap is formed between the outer peripheral surface of the plunger 35 and the inner peripheral surface of the plunger cylinder 30 and between the outer peripheral surface of the plunger 35 and the inner peripheral surface of the raw material transfer cylinder portion 45. The injection amount is constant without the backflow of the raw material M2.

Thereafter, when the injection molding is to be continued, the above-mentioned plasticization measuring step, raw material transfer step and injection step are repeated. It is efficient to carry out the plasticizing and measuring step in parallel with the injection step.

FIG. 6 shows another example of the injection device of the present invention.
Are attached. By providing this plate 50, the plastic raw material M1 passes through the through-hole 51 at the time of raw material delivery shown in FIG.
It becomes a plurality of cords and is pushed into the raw material transfer cylinder 45A. Since the plastic raw material M1 is extruded in a plurality of cords, the surface area of the plastic raw material M1 increases, so that the amount of gas in the plastic raw material M1 that escapes through the surface of the plastic raw material M1 increases. In addition, degassing can be performed more efficiently.

When the plate 50 is provided, the plastic raw material M is formed through the through hole 51 of the plate 50.
Since the gas in 1 can be efficiently extracted, the inner diameter of the raw material transfer cylinder 45A may be substantially equal to the inner diameter of the plasticizing and measuring cylinder 20A.

[0031]

As shown and described above, according to the present invention, a plastic thermosetting resin raw material is fed from a plasticizing measuring cylinder to a raw material transfer cylinder, and the surface area of the plastic raw material is increased. Therefore, degassing can be sufficiently performed from the plastic material. In addition, according to the present invention, the plunger does not need the function of plasticizing and measuring the raw material, and it is not necessary to provide a screw groove for plasticizing and measuring the outer circumference. Therefore, there is no gap between the inner peripheral surface of the plunger cylinder and the inner peripheral surface of the raw material transfer cylinder and the outer peripheral surface of the plunger, and the backflow of the raw material can be prevented during injection. Further, in the injection device of the present invention, there is no need to provide a vacuum suction device or the like for degassing the raw material. .

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a plasticizing and measuring state of an injection device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a raw material delivery state in the embodiment.

FIG. 3 is a sectional view showing a raw material transfer state in the embodiment.

FIG. 4 is a sectional view showing an injection state in the embodiment.

FIG. 5 is a perspective view showing an example of a raw material transfer member.

FIG. 6 is a sectional view showing a main part of an injection device according to another example of the present invention.

FIG. 7 is a cross-sectional view illustrating an example of a conventional injection device.

[Description of Signs] 10 Injection device 20 Plasticizing and measuring cylinder 25 Feed screw 30 Plunger cylinder 35 Plunger 40 Raw material transfer member 41 Shutter plate 45 Raw material transfer cylinder M raw material M1 Plastic raw material M2 Degassed plastic raw material

Claims (3)

(57) [Claims] 1. A thermosetting resin injection device for injecting a raw material which is fed from the tip of the plasticizing measuring cylinder by a feed screw in the plasticizing measuring cylinder and supplied to the plunger cylinder from the plunger cylinder as the plunger advances. A raw material transfer member having a shutter plate formed on an outer surface of a raw material transfer cylinder portion having an inner diameter larger than the inner diameter of the plasticizing and measuring cylinder. Part is located in communication with the plasticizing metering cylinder tip, while the plasticizing metering cylinder tip is closed while the shutter plate closes the plasticizing metering cylinder tip during plasticizing metering and injection, and the material transfer cylinder part is positioned in communication with the plunger cylinder. Wherein the plasticizing measuring cylinder is provided so as to be movable between the tip of the cylinder and the plunger cylinder. Injection device that thermosetting resin. 2. The thermosetting resin injection device according to claim 1, wherein a plate having a plurality of through holes is attached to a tip of the plasticizing measuring cylinder. 3. The method according to claim 1, wherein the inner diameter of the raw material transfer cylinder is substantially equal to the inner diameter of the plasticizing and measuring cylinder.
A thermosetting resin injection device, wherein a plate having a plurality of through holes is attached to a tip of the plasticizing measuring cylinder.