JP2001170955A - Injection molding method, injection molding apparatus, and method for cleaning plastic material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a molded article having no flaw from an aspect of quality by removing foreign matter or the like sticking to a plastic material. SOLUTION: In an injection molding method, a charged plastic material 15 is irradiated with X-rays or ultraviolet rays under vacuum and the irradiated cleaned plastic material 16 is used to be injection-molded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection molding method for molding a plastic molded article using a plastic material, an injection molding apparatus for performing the method, and a method for cleaning a plastic material.

[0002]

2. Description of the Related Art Conventionally, an injection molding apparatus for molding a plastic molded article by injection molding is disclosed in Japanese Patent Application Laid-Open No. 7-65886 as a method for removing static electricity in the plastic molding apparatus.
The technology disclosed in Japanese Unexamined Patent Publication (Kokai) No. H10-214,878 is disclosed. This technique will be described with reference to FIG.

[0003] A material tank 151 for charging a plastic material Y in the form of pellets and a hopper 153 of a dryer 152 are connected by a suction line 154.
The plastic material Y in the material tank 151 is sucked into the hopper 153 by the suction force of the suction loader 155 connected to the
2 Then, the plastic material Y is dried in the dryer 152. Further, a lower portion of the dryer 152 and a supply hopper 158 disposed on a hopper 157 of the injection molding machine 156 are connected by a suction pipe 159, and the dryer 152 is suctioned by a suction loader 160 connected to the supply hopper 158. After sucking the dried plastic material Y in the supply hopper 158, the injection molding machine 15
The hopper 157 supplies the plastic material Y to the injection molding machine 156.

Then, the plastic material heated and melted from the injection molding machine 156 is injected in a state where a pair of molding dies 161 and 162 arranged in front of the injection molding machine 156 are closed. A plastic molded article is molded in a cavity (not shown) to be formed. Thereafter, the pair of molding dies 161 and 162 are opened, and the plastic molded product Z molded in the cavity is removed by, for example, an automatic removal machine 163 to obtain a plastic molded product having a desired shape. At this time, dust, dirt, or powder of the plastic material generated during the contact between the plastic materials or the sliding in the suction pipe is attached to the pellet-shaped plastic material put into the material tank 151. Since it is lighter than the plastic material, the suction loader 155 and the suction loader 160 remove it by suction.

In the above-described injection molding apparatus, the plastic material Y slides in the suction pipe 154 and the suction pipe 159 when the plastic materials Y come into contact with each other. In the Japanese Unexamined Patent Application Publication No. 7-65886, the suction pipes 154 connected to the hoppers 153 and 157 are electrically charged, so that the supply of the plastic material Y to the hoppers 153 and 157 cannot be performed smoothly. 159 are provided with ion generators 181 and 182, respectively. Then, the air is ionized by the ion generators 181 and 182, and the ionized air is blown.
54, 159, or by irradiating ions to the plastic material Y passing through the conduits in the ion generators 181, 182, the static electricity of the plastic material Y is removed. The supply was made smooth.

[0006]

In the above-mentioned prior art, ions are brought into contact with a plastic material by blowing air, that is, ions of static elimination are brought into contact with the plastic material by blowing air or the plastic material is directly irradiated with ions. And to make the charged plastic material electrically neutral. However, when the plastic material is in a lump-like state and moves in the pipeline, the static elimination ions do not reach the plastic material inside the lump by blowing air, and the plastic material is directly irradiated with ions. Also, the ions do not reach the inside of a lump-like state. The phenomenon in which the plastic material moves like a lump and moves in the pipeline is caused by the suction loader 155.
Alternatively, when the operation of the suction loader 160 is started, it is particularly likely to occur before the suction force is stabilized. Therefore, due to this phenomenon, it has been difficult to make ions uniformly contact the plastic material.

Further, in the above-described injection molding apparatus, as described above, since the static removal of the pellet-shaped plastic material is insufficient, the surface of the insufficient plastic material is covered with dust, dirt, or plastic. The powder of the material is strongly adhered by the static electricity, and the dust, dust, or the powder of the plastic material is discharged from each suction loader 15.
5, is transferred into the hopper 157 of the injection molding machine 156 without being removed by suction, and is molded together with the plastic material by the injection molding machine 156;
Foreign matter was mixed inside the plastic molded product.
Therefore, the foreign matter causes a quality defect in the plastic molded product. The quality defect includes, for example, a phenomenon in which a foreign substance in a prism used as a light source of a backlight of a liquid crystal display causes diffuse reflection and appears as a white spot on a display panel.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention according to claims 1, 2 and 3 is to remove foreign substances and the like adhering to a plastic material and reduce defects in quality. It is an object of the present invention to provide an injection molding method for obtaining a molded article having no molding.

An object of the invention according to claims 4, 5, 6 or 7 is to provide an injection molding apparatus for performing the injection molding method according to the invention according to claims 1, 2 or 3.

An object of the present invention according to claim 8 is to provide a method for cleaning a plastic material, which removes foreign substances and the like adhering to the plastic material and obtains a molded product having no quality defect.

[0011]

According to a first aspect of the present invention, there is provided an injection molding method, comprising irradiating a charged plastic material with X-rays or vacuum ultraviolet rays and then using the plastic material. And injection molding.

According to a second or third aspect of the present invention, in the injection molding method, the charged plastic material and the foreign matter
Injection molding is performed using a plastic material from which foreign matter has been removed by irradiating a wire or vacuum ultraviolet rays.

According to a fourth aspect of the present invention, in the injection molding apparatus, an X-ray or vacuum ultraviolet irradiation means for electrically neutralizing a charged plastic material and an X-ray or vacuum ultraviolet irradiation means are provided. Foreign matter removing means for removing foreign matter from the electrically neutralized plastic material.

According to a fifth, sixth or seventh aspect of the present invention, in an injection molding apparatus, a storage means for storing a plastic material, and an electric neutralizing means for electrically charging the charged plastic material attached to the storage means. X-ray or vacuum ultraviolet irradiation means, diffusion means for sowing and diffusing a plastic material in the storage means, and foreign matter attached to the storage means for removing foreign matter from the electrically neutralized plastic material Removing means.

According to an eighth aspect of the present invention, in the method for cleaning a plastic material, the plastic material is irradiated with X-rays or vacuum ultraviolet rays to remove foreign matter or plastic material powder and the plastic material which are electrically attached to the plastic material. Separation by making it electrically neutral,
Obtain a plastic material free of foreign matter or plastic material powder.

In the injection molding method according to the first aspect of the present invention,
By irradiating the charged plastic material with X-rays or vacuum ultraviolet rays, and then performing injection molding using this plastic material, the plastic materials charged by the irradiation of the X-rays or vacuum ultraviolet rays are neutralized to separate foreign substances, and the foreign substances are separated. The injection molding is performed using the plastic material after the separation.

In the injection molding method according to the second or third aspect of the present invention, the charged plastic material and the foreign matter are irradiated with X-rays or vacuum ultraviolet rays, and injection-molded using the plastic material from which the foreign matter has been removed. The plastic material charged by the irradiation of X-rays or vacuum ultraviolet rays is neutralized, the plastic material and the foreign matter are separated, the foreign matter is removed, and the plastic material after the removal of the foreign matter is subjected to injection molding.

In the injection molding method according to the third aspect of the present invention,
In addition to the above operation, the irradiation of X-rays or vacuum ultraviolet rays and the removal of foreign matter are performed before the supply of the plastic material to the injection cylinder of the injection molding apparatus, so that the cleaned plastic material is supplied to the injection cylinder. , Melting and injection are performed.

In the injection molding apparatus of the invention according to claim 4,
X-ray or vacuum ultraviolet irradiation means for electrically neutralizing the charged plastic material, and foreign matter removing means for removing foreign matter from the plastic material electrically neutralized by the vacuum ultraviolet irradiation means. The plastic material charged by the X-ray or vacuum ultraviolet irradiation means is electrically neutralized to separate foreign matter, and the foreign matter is removed from the injection molding apparatus by the foreign matter removing means.

In the injection molding apparatus of the invention according to claim 5, 6, or 7, the storage means for storing the plastic material,
X-ray or vacuum ultraviolet irradiation means for electrically neutralizing the charged plastic material attached to the storage means, diffusion means for sowing and diffusing the plastic material in the storage means, Having foreign matter removing means attached to the means for removing foreign matter from the electrically neutralized plastic material, whereby the plastic material stored in the storing means is sowed in the storing means by the diffusion means, The plastic material blown up by the X-ray or vacuum ultraviolet irradiation means attached to the storage means is electrically neutralized to separate foreign matter, and the foreign matter is removed from the injection molding apparatus by the foreign matter removing means.

According to the injection molding apparatus of the invention according to claim 6,
In addition to the above operation, the storage means has a means for preventing leakage of X-rays or vacuum ultraviolet rays, so that the X-rays or vacuum ultraviolet rays are reflected or absorbed in the storage means and stopped.

In the injection molding apparatus of the invention according to claim 7,
In addition to the above operation, the storage means has a reflecting member at a position corresponding to the irradiation range of the X-ray or the vacuum ultraviolet ray, so that the X-ray or the vacuum ultraviolet ray emitted from the X-ray or the vacuum ultraviolet ray irradiating device can reflect the reflecting member. And the reflected light spreads all over the interior of the storage means.

In the method of cleaning a plastic material according to the present invention, the plastic material is irradiated with X-rays or vacuum ultraviolet rays to remove foreign matter or the plastic material powder and the plastic material that are electrically attached to the plastic material. By obtaining a plastic material to which the foreign matter or the plastic material powder is not adhered by making it neutral to be neutral, the charged plastic material and the foreign matter or the plastic material powder are adhered to each other.
When irradiated with a line or vacuum ultraviolet rays, each is neutralized to become a substance in an electrically neutral state, the plastic material and the foreign material or the powder of the plastic material are separated from each other, and a purified plastic material is obtained.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments will be described. In the embodiment of the present invention, X-rays (electromagnetic waves having a wavelength of 50 ° (angstrom) or less, for example, about 1 °) are used to separate foreign matter or plastic material powder from a charged plastic material.
Vacuum ultraviolet rays (electromagnetic waves having a wavelength of about 2000 to 50 degrees) can be used instead of the lines. Further, as the X-ray irradiating device as the irradiating means, a vacuum ultraviolet irradiating device for irradiating vacuum ultraviolet instead of X-ray can be used.

(Embodiment 1) FIGS. 1 and 2 show Embodiment 1, and FIG. 1 is a schematic configuration diagram of an entire injection molding apparatus.
FIG. 2 is an enlarged sectional view around the plastic material supply device.

First, the injection molding apparatus will be described. In FIG. 1, an injection molding machine, which is a base of the injection molding apparatus,
On a substantially left side of the base 1, a mold clamping device 50 in which a pair of dies 3, 4 for molding a plastic molded product is mounted so as to open and close the dies.
And an injection device 51 that supplies a molten plastic material to the pair of molds 3 and 4, and a plastic material supply device 52 that supplies the injection device 51 with a plastic material
And a control device (not shown) for controlling these. The mold clamping device 50 is fixed by attaching a driving unit 55 that makes the movable platen 54 to which the mold 3 of the pair of molds is attached movable, and the mold 4 of the pair of molds. And a fixed platen 56. Injection device 5
1 includes a nozzle (not shown) on the fixed platen 56 side, and heats and softens a plastic material supplied from the hopper 5 above the injection cylinder 2 into the injection cylinder 2 so that the plastic material is paired with the nozzle. Is injected and filled into a cavity (not shown) formed between the molds 3 and 4.

The plastic material supply device 52 for supplying a plastic material to the injection cylinder 2 is provided with a hopper 5 as a rectangular cylindrical storage means which is mounted on the upper right side of the injection cylinder 2 and has a conical lower side. An irradiating device 12 is provided as an irradiating means, which is attached in close contact with a substantially central side wall surface of the hopper 5 and is capable of irradiating X-rays toward the inside of the hopper 5. The upper portion of the hopper 5 has a generally rectangular cylindrical shape and is formed mainly of glass having a thickness of 0.5 mm (because glass having a thickness of 0.5 mm or more does not transmit X-rays). The pyramid is made of stainless steel, and is connected to the injection cylinder 2 at the lower stainless steel tubular section 5a. In the present embodiment, the reason why glass is used for the hopper 5 is that the diffusion state of the plastic material in the hopper 5 described later can be confirmed, and the air volume can be adjusted based on this. In order to further supply the plastic material, the hopper 5 of the plastic material supply device 52 is provided with a storage tank 6 for storing the plastic material supplied from the supply device 60 via the pressure pipe 33 and the hopper 5 and the storage tank 6. The supply pipe 9 to be connected is connected. A material transporter 34 is provided below the storage tank 6 to transfer the plastic material to the hopper 5 via the supply pipe 9.

Further, a removing device 7 provided with a suction device for sucking and removing foreign matter (dust, dust, and powder of plastic material lighter than plastic material in pellet form) in the hopper 5.
And a removal pipe 10 connecting the hopper 5 and the removal device 7 are connected. The removing device 7 and the removing pipe 10 constitute foreign matter removing means. The hopper 5 is connected to a diffusion means 57 which is connected to a motor and has a built-in fan so as to blow air from the entire circumference of the lower end of the cylindrical shape toward the upper side and the upper side. As shown in FIG. 2, the diffusion means 57 has a ring-shaped outlet 19 provided inside the quadrangular pyramid so as to allow air to flow along the inner periphery in the hopper 5 and upward toward the center. The air for diffusing the groove 18 and the plastic material 15 with foreign matter is supplied, that is, the plastic material 15 with foreign matter falling from the supply pipe 9 into the hopper 5 is blown up by air blown from below. A diffusion device 8 (FIG. 1) incorporating a motor connected to a fan that sends air to diffuse.
) And the diffusion tube 1 connecting the hopper 5 and the diffusion device 8.
1 and 1. In addition, a control device (not shown) for controlling the injection molding device is provided in addition to the above.

In FIG. 2, inside the hopper 5, a supply pipe 9 and a removal pipe 10 arranged on the upper side are respectively opened downward, and are also directed upward along the inner circumference. A diffusion tube 11 disposed below the opening is opened.
An opening 5b of a square tubular portion 5a is formed. The opening of the supply pipe 9 is not positioned on an extension of the opening diameter d of the opening 5b of the square tubular portion 5a (that is, an extension of the opening shape). That is, the plastic material dropped from the supply pipe 9 does not directly enter the opening 5b of the square tubular portion 5a when dropped by itself. Further, an X-ray irradiator 12 attached to the outside of the hopper 5 and capable of irradiating X-rays toward the inside of the hopper 5.
Irradiation hole 13 for taking in the X-ray of
Supply pipe 9 for supplying plastic material into hopper 5
Are provided so as to intersect (orthogonal in the figure) with respect to the extension of the opening.

Therefore, the plastic material supplied from the supply pipe 9 is exposed to the X-rays radiated from the irradiation hole 13 and also X-rays when the plastic material soars by the air blown from below the inside of the hopper 5. Because it will be exposed to X-rays when it falls and then soars and falls, and its posture changes when the plastic material moves (for example, the orientation changes as the pellets rotate) The surface of the plastic material is almost uniformly exposed to X-rays. Therefore, the plastic material and the foreign material attached to the surface thereof or the foreign material entering the hopper 5 together with the plastic material are also exposed to the X-ray.

Next, an injection molding method using the injection molding apparatus having the above configuration will be described. In the present embodiment, using an acrylic pellet material as a plastic material,
Injection molding of a lens as an optical component will be described. However, it is a matter of course that the present embodiment can be applied to a prism or the like which is an optical component other than a lens, or a plastic molded product which does not allow foreign matter. As shown in FIG. 1, first, the supply pipe 9 is supplied from the storage tank 6 already stored from the supply device 60 via the pressure feed pipe 33 by the material transporter 34.
, The plastic material is transferred to the hopper 5. At this time, a foreign substance consisting of material powder due to collision between the plastic materials and dust (dust, dust) other than the plastic material adheres to the plastic material due to static electricity generated due to friction or the like during transport, and the plastic with the foreign substance is attached. The material 15 (see FIG. 2) is supplied into the hopper 5 from the opening of the supply pipe 9.

As shown in FIG. 2, air is continuously blown into the lower ring-shaped groove 18 in the hopper 5 from the diffusion tube 11 in advance, and the inside of the hopper 5 is A turbulence is caused by the air flowing toward the upper side as indicated by arrow B and the air flowing toward the center. Air is continuously sucked from the inside of the hopper 5 from the opening of the removal pipe 10 as shown by the arrow C. Further, X-rays are continuously emitted from the irradiation hole 13 by the irradiation device 12 as shown by an arrow E. Further, as shown by an arrow F, the irradiated X-ray has a thickness of 0.5 mm.
Since the light does not go out of the hopper 5 through the glass wall of not less than mm, the light is irregularly reflected in the hopper 5 and reaches every corner inside the hopper 5.

Therefore, as shown by the arrow A, the plastic material 1 with foreign matter introduced into the hopper 5 from the supply pipe 9
5 is exposed to X-rays immediately after being supplied from the supply pipe 9 to neutralize static electricity, or is soaked and diffused by turbulence from below in the hopper 5 and is irradiated with X-rays. Ions are generated in the vicinity of the foreign matter-containing plastic material 15 to neutralize the charged foreign matter-containing plastic material 15, or thereafter, the foreign matter-containing plastic material 15 moves toward the opening of the square cylindrical portion. At this time, the charged plastic material 15 with foreign matter is neutralized by being irradiated with the X-rays applied to the plastic material 15, and is separated into the plastic material 16 and the foreign matter 17.

The foreign matter 17 rises by the turbulence and is sucked into the opening of the removal pipe 10 above the hopper 5 as shown by an arrow C, and the plastic material 16 heavier than the foreign matter 17 becomes a square tubular portion 5a at the bottom of the hopper 5. Into the opening 5b, and the arrow D
Is supplied to the upper side of the injection cylinder 2 as shown by. The balance between the air flow indicated by the arrow B and the air flow indicated by the arrow C is adjusted by a control means (not shown) such that the foreign matter 17 always rises and is sucked into the removal pipe 10 (in the present embodiment, the arrow B is used). Side is 117.6 kPa (1.2 kgf / c
corresponding to m ^2), arrow C side is 98 kPa (1.0 kgf /
irradiation intensity of cm ² are appropriate) it is in) to have, also the X-ray is set to 0.01 Sv / h. As shown in FIG. 1, the plastic material 16 having undergone the above-described process is supplied to the injection cylinder 2, and is heated and softened inside the injection cylinder 2 by a screw (not shown) and a heating device of the injection device 51, so that the pair of dies 3 is formed. 4 is fed in the direction of a mold cavity (not shown), and is injected and filled into the cavity to form a lens having a desired shape.

According to the present embodiment, ions are generated so that the X-rays can reach all corners in the hopper 5 and irradiate all the plastic material 15 with foreign matter introduced into the hopper 5 without fail. All the foreign-material-containing plastic materials 15 can be made electrically neutral. The neutralized foreign matter 17 that has been neutralized is separated from the hopper 5.
The turbulent air blown from the diffusion pipe 11 disposed below the hopper 5 rises above the hopper 5 and is sucked and removed from the removal pipe 10.
Thus, the injection cylinder 2 can be supplied with only the plastic material 16. Therefore,
If the plastic material 16 is injection-molded,
Lens without quality defects due to the above.
The absence of quality defects includes, for example, the following. There is no generation of white foreign matter recognized when viewed through the molded lens. There is no black foreign matter recognized when viewed through a molded lens. No bright spots appear when light passes through the molded lens.

In this embodiment, the hopper 5 has a thickness of 0.5
Although a glass having a thickness of not less than mm was used, a resin such as acrylic having a plate thickness that does not allow X-rays or vacuum ultraviolet rays to pass therethrough (X-rays having a plate thickness of not less than 1.5 mm), polycarbonate, and the like may be used instead. . In the case of a substance other than the above-mentioned metals, a multi-layered structure in which the outer periphery of the hopper is surrounded by a metal may be used. Further, in addition to the diffusion means using compressed air from below the hopper 5 shown in the present embodiment, an opening is formed below (downstream side) the irradiation device 12 provided on the side surface of the hopper 5, and the supply pipe 9 is provided. Air with a high discharge pressure is blown so as to blow up the plastic material supplied from. That is, a diffusion pipe 43 (see FIG. 2) indicated by a broken line is directly attached to the side surface of the hopper 5 to blow air into the hopper 5 or to a position in a falling direction of the plastic material supplied from the supply pipe 9. Alternatively, another diffusion pipe 20 (see FIG. 2) indicated by a broken line may be attached to the bottom of the hopper 5 and air may be blown toward the upper part of the hopper 5.

In addition to the continuous irradiation of X-rays or vacuum ultraviolet rays shown in the present embodiment, intermittent irradiation may be performed according to the intermittent supply of the plastic material supplied from the supply pipe 9. . That is, even if the supply is intermittent, if the foreign matter after the static electricity is already neutralized is removed from the hopper, the foreign matter is not attached to the plastic material in the hopper, so that the molding is good. Therefore, it is only necessary to neutralize static electricity on the plastic material newly supplied into the hopper. In addition, the plastic material supplied into the hopper is diffused by the air flow supplied into the hopper and is soared. Since the material is at a high position and irradiation may be interrupted until the material falls, intermittent irradiation may be performed.

Further, in addition to the X-ray irradiation intensity shown in the present embodiment, the irradiation intensity may be adjusted as appropriate according to the size of the hopper, the flow rate of the material and the flow speed.
Further, the installation position of the removal tube 10 shown in the present embodiment is located above the hopper 5, but in addition to this position, the removal tube 21 (shown by a broken line) is located at a position higher than the X-ray irradiation position on the side surface of the hopper 5. 2 (see FIG. 2).

(Embodiment 2) FIG. 3 shows Embodiment 2 and is a longitudinal sectional view of a supply pipe to which an X-ray irradiator and foreign matter removing means are attached. The injection molding apparatus of the present embodiment
In addition to the X-ray irradiator and the foreign matter removing means attached to the hopper in the first embodiment, an X-ray irradiator and a foreign matter remover are attached to the supply pipe, and only the added portion is the first embodiment. Unlike the first embodiment, the other parts are the same as those in the first embodiment. Therefore, only different parts will be described, and drawings and descriptions of the same parts will be omitted.

In FIG. 1, an outer wall of a supply pipe 9 constituting a plastic material supply device 52 for supplying a plastic material to the hopper 5 is provided with an X-ray irradiation device 22 as irradiation means, as shown in FIG. , A removing pipe 23 attached downstream thereof, and a removing port 25 serving as an opening of the removing pipe 23.
And a filter 26 covering the filter. The other end of the removing tube 23 is connected to a removing device (not shown) (which may also be used as the removing device 7 of the first embodiment) provided with a suction means for sucking and removing foreign matter. The filter 26, the removing tube 23, and a removing device (not shown) constitute a foreign matter removing unit. Other configurations are the same as those of the first embodiment.

X-rays are transferred from the upstream storage tank 6 (see FIG. 1) in the supply pipe 9 in the direction of the arrow G as shown by the arrow H from the irradiation port 24 formed in the pipe wall of the supply pipe 9. Irradiated on the plastic material 15 with foreign matter, and the static electricity between the plastic material and the foreign matter attached by static electricity is X
Neutralized by the irradiation of the radiation, the plastic material and the foreign matter are electrically neutralized and separated from each other. Next, the separated foreign matter 17 is sucked through a filter 26 provided in a removal port 25 formed on the downstream side of the supply pipe 9 and is removed by the removal pipe 2.
3 is removed in the direction of arrow I. Therefore, only the neutralized plastic material 16 does not pass through the filter 26 provided in the removal port 25, passes through the removal pipe 9, and is sent into the hopper 5 (see FIG. 2). And plastic material 16
Is supplied into the hopper 5, and again, as described in the first embodiment, the X-ray irradiation device 12 attached to the hopper 5
Thereby, irradiation of the plastic material 16 is performed, electrical neutralization of the plastic material is performed again, and foreign matter is removed. Other injection molding methods are the same as in the first embodiment.

According to the present embodiment, in addition to the effect of the first embodiment, the foreign matter is removed by both the supply pipe 9 and the hopper 5, so that the foreign matter removing effect is further enhanced. If the foreign matter removing effect in the supply pipe 9 is sufficient, the foreign matter removing means in the hopper 5 may be omitted.

(Embodiment 3) FIG. 4 shows Embodiment 3 in which a part near a storage tank to which an X-ray irradiator and a foreign matter removing means are attached is cut away. The injection molding apparatus according to the present embodiment includes an X-ray irradiator, a foreign substance removing unit, and a diffusing unit in addition to an X-ray irradiator, a foreign substance removing unit, and a diffusing unit attached to the hopper according to the first embodiment. And only the added portion is different from the first embodiment, and the other portions are the first embodiment.
Therefore, only different portions will be described, and drawings and descriptions of the same portions will be omitted.

In FIG. 4, a storage tank 6 serving as a storage means has a lower portion formed in a truncated conical shape and an upper portion formed in a bottomed cylindrical shape. An X-ray irradiating device 26 as an irradiating means is disposed on a substantially central side wall surface of the storage tank 6, and a removal pipe 32 is connected to an upper wall surface together with a pressure feeding pipe 33.
The removing tube 32 is connected to the removing device 7 (see FIG. 1) similar to the first embodiment. The removing pipe 32 and the removing device 7 constitute a foreign matter removing means. Further, a hot air blower 27 as a diffusion means for sending hot air into the inside of the storage tank 6 is connected via a hot air pipe 29 to a lower portion of the storage tank 6. A ring-shaped groove 6a is formed in a portion where the hot air pipe 29 is connected to the lower portion of the storage tank 6, and the hot air is blown upward through the groove 6a. .
Therefore, a diffusion means having basically the same structure as that of the first embodiment is provided, and an opening 6b to the supply pipe 9 is provided at a lower center in the storage tank 6, and an opening is provided at an upper part of the storage tank 6. The openings of the pressure feed pipe 33 and the removal pipe 32 are formed at positions outside the opening diameter d of 6b. Other configurations are the same as those of the first embodiment.

In the present embodiment, warm air is blown into the inside of the storage tank 6 from the lower side of the storage tank 6 through a warm air pipe 29 through a warm air pipe 29 in the direction of arrow M in a ring shape. The plastic material 15 with foreign matter introduced from above is sowed up and diffused and dried. That is, the plastic material 15 with the foreign matter introduced from the pressure feed pipe 33 is exposed to the X-ray irradiated from the X-ray irradiator 26 in the direction of the arrow J and is electrically neutralized by the neutralization. The foreign matter 17 which has been separated into 16 and foreign matter 17 and is blown up by the warm air is sucked from the removing pipe 32 and stored in the removing device 7 (see FIG. 1). Therefore, only the electrically neutralized and dried plastic material 16 is filled with the lower opening 6b of the storage tank 6.
From the hopper 5 via the supply pipe 9 by the material transporter 34
Is transferred to It is to be noted that what is indicated by a dotted line below the irradiation device 26 is a hot air tube 30, and by additionally arranging it in addition to the hot air tube 29 on the lower side of the storage tank 6, drying and diffusion are more facilitated. It can be performed sufficiently.
Other injection molding methods are the same as in the first embodiment.

According to the present embodiment, in addition to the effect of the first embodiment, since foreign matter is removed in the storage tank 6, the foreign matter does not adhere to the inner wall of the supply pipe 9. Therefore, the inner wall of the supply pipe 9 is always clean, the plastic material 16 can be smoothly transferred, and the foreign matter is removed again by the X-ray irradiation in the hopper 5, so that the foreign matter removing effect is further enhanced.

When the foreign matter removing effect in the storage tank 6 is sufficient, the foreign matter removing operation in the hopper 5 and the foreign matter removing means may be omitted. When a higher foreign matter removal effect is required, as described in the second embodiment,
X-ray irradiating means including X-ray irradiator 22 (see FIG. 3) and downstream filter 26 (see FIG. 3) on the outer wall surface of supply pipe 9 connecting hopper 5 and storage tank 6, and foreign matter It is also possible to use a removing means together.

(Embodiment 4) FIG. 5 shows Embodiment 4 and is an enlarged sectional view of a hopper. The injection molding apparatus of the present embodiment is obtained by adding a reflection member in the hopper of the first embodiment, and the other parts are the same as those of the first embodiment.
Only different portions will be described, and the drawings and description of the same portions will be omitted. Also, in FIG. 5, the same members as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In FIG. 5, a reflecting member 35 for reflecting X-rays is provided on the inner wall of the hopper 5 corresponding to an X-ray irradiation area directly irradiated from the X-ray irradiation device 12.
A stainless steel plate is used for the reflection member 35, and the reflection surface 35a
Is mirror-finished, and is set to have an area slightly larger than the irradiation area of the directly irradiated X-rays. Other configurations of the injection molding apparatus are the same as those of the first embodiment.

The X-rays emitted from the X-ray irradiating device 12 are reflected by the reflecting surface 35 a of the reflecting member 35, and the reflected light is spread throughout the hopper 5. Other injection molding methods are the same as in the first embodiment.

According to the present embodiment, in addition to the effects of the first embodiment, there is no absorption of X-rays as compared with a state in which no reflection member is provided in the hopper, so that a sufficient amount of plastic material can be obtained. Irradiation can be performed. As a result, it is possible to increase the effect of separating the plastic material and the foreign matter in the plastic material with the foreign matter.

In this embodiment, the reflection member is provided in the direct X-ray irradiation area. However, if a reflection member is provided on the entire inner wall of the hopper, or if the reflection surface is made to be irregularly reflected, the reflection member may be provided. Needless to say, the effect is further improved.

(Fifth Embodiment) FIG. 6 shows a fifth embodiment and is a front view of a mechanism for attaching an irradiation device to a hopper.
The injection molding apparatus of the present embodiment is different from the first embodiment only in the mounting structure of the irradiation device to the hopper, and the other parts are the same as those of the first embodiment. The description is omitted. Also, in FIG. 6, the same members as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In FIG. 6, a stopper 36 having a substantially ring shape and having protrusions 36 a at both ends thereof is fitted around the outer periphery of the hopper 5, and the stopper 36 is tightened by a set screw 37. The hopper 5 is fixed to the lower periphery. The stopper 36 has two bent screw holes (not shown) for fixing the X-ray irradiating device 12, and a bent angle 42 is erected. A stay 39 is integrally formed on the lower surface of the X-ray irradiation device 12 having a box-like external shape.
And an elongated hole 40 corresponding to a screw hole (not shown) of the angle 42 is formed on a wall surface thereof. Angle 4
2, two setscrews 41 are screwed into the screw holes (not shown) through the long holes 40 of the stays 39.
Is fixed. The long hole 40 is a long hole in the horizontal direction so that the pressing force for pressing the X-ray irradiation device 12 against the hopper 5 can be adjusted. A buffer member 38 made of neoprene rubber containing lead is bonded and fixed to the entire outer peripheral surface of the box-shaped X-ray irradiation device 12. The buffer material 38 has an irradiation hole 1 of the hopper 5 so as not to hinder X-ray irradiation between the X-ray irradiation device 12 and the hopper 5.
3 (see FIG. 2), a through-hole (not shown) is formed. The X-ray irradiator 12 presses the buffer material 38 so as to be closely attached to the hopper 5 so as to be attached to the hopper 5.
The position is adjusted at 0 and fixed by screws 41.

According to the present embodiment, in addition to the effects of the first embodiment, the X-ray irradiating device 12 can be tightly fixed to the side wall of the hopper 5 via the buffer material 38, and the X-ray can be The X-ray does not leak from the gap between the X-ray irradiating device 12 and the hopper 5 because it is reflected or absorbed inside. Also, since the buffer material 38 itself is made of lead-containing neoprene rubber, it absorbs X-rays and does not leak it.

In the embodiment of the present invention, a plastic material used for an injection molding apparatus is irradiated with X-rays (having a wavelength of 50).
ÅHereinafter, by irradiating electromagnetic waves of, for example, electromagnetic waves of about 1 紫外線 or vacuum ultraviolet rays (wavelength of 2000 to 50Å), ions generated in the vicinity of the plastic material neutralize static electricity of the plastic material and foreign substances adhering thereto. Then, the two are neutralized and separated, and the separated foreign matter is removed in a state of being suspended by a difference in mass from the plastic material. The plastic material thus obtained from which foreign matter has been removed can be used not only as a material for injection molding, but also as a material for compression molding or a material for extrusion molding.

In the embodiment of the present invention, in a mode in which a plastic material is molded by injection molding, air is blown up from the lower side in the hopper to diffuse the plastic material and irradiate X-rays or electromagnetic waves of vacuum ultraviolet rays. However, in the case of vacuum ultraviolet rays, gases such as Ar gas and He gas other than the above are used instead of air because they are easily absorbed by O ₂ , N ₂ , and CO _2. May be. In the supply pipe described in the second embodiment and the storage tank described in the third embodiment (that is, in the plastic material supply apparatus), when irradiating vacuum ultraviolet electromagnetic waves, O ₂ , N ₂ , and CO ₂ are excluded. The static electricity may be neutralized while flowing a gas such as Ar or He.

The following technical ideas are derived from the embodiments of the present invention. (Supplementary Note) (1) A method for molding a plastic molded article, which comprises irradiating a charged plastic material with X-rays or vacuum ultraviolet rays and then molding using the plastic material.

According to appendix (1), the plastic material charged by irradiation with X-rays or vacuum ultraviolet rays is neutralized and molded with the neutralized plastic material, so that foreign substances and the like adhering to the plastic material are removed. And
A plastic molded product without quality defects can be obtained.

(2) A method of molding a plastic molded article, which comprises irradiating a charged plastic material and foreign matter with X-rays or vacuum ultraviolet rays and using the plastic material after removing the foreign matter.

According to appendix (2), the plastic material charged by irradiation with X-rays or vacuum ultraviolet rays is neutralized, the plastic material is separated from the foreign matter, the foreign matter is removed, and the plastic material after the foreign matter is removed is removed. Therefore, a plastic molded product having no quality defect can be obtained.

[0062]

According to the first aspect of the present invention, the plastic material charged by irradiation with X-rays or vacuum ultraviolet rays is neutralized to separate foreign substances, and injection molding is performed with the plastic material after the foreign substances are separated. As a result, it is possible to remove foreign substances adhering to the plastic material and obtain a molded article free from defects in quality.

According to the second or third aspect of the present invention, X
The plastic material charged by the irradiation of the line or vacuum ultraviolet rays is neutralized, the plastic material and the foreign matter are separated, the foreign matter is removed, and the plastic material after the removal of the foreign matter is subjected to injection molding. And a molded product without the same can be obtained.

According to the third aspect of the present invention, in addition to the above effects, the plastic material after being cleaned is supplied to the injection cylinder, and melting and injection are performed. Goods can be obtained.

According to the fourth aspect of the invention, the plastic material charged by the X-ray or vacuum ultraviolet irradiation means is electrically neutralized to separate foreign matter, and the foreign matter is removed by the foreign matter removing means in the injection molding apparatus. Is excluded from
A molded article without quality defects can be molded.

According to the fifth, sixth or seventh aspect of the present invention, the plastic material stored in the storage means is sowed in the storage means by the diffusion means, and the plastic material of X-ray or vacuum ultraviolet light attached to the storage means. The plastic material raised by the irradiating means is electrically neutralized to separate foreign matter, and the foreign matter is removed from the injection molding apparatus by the foreign matter removing means, so that it is possible to mold a molded article having no quality defect. it can.

According to the sixth aspect of the present invention, in addition to the above-mentioned effects, since the X-rays or vacuum ultraviolet rays are reflected or absorbed in the storage means and stopped, leakage of the X-rays or vacuum ultraviolet rays outside the injection molding apparatus is prevented. Can be prevented.

According to the seventh aspect of the invention, in addition to the above effects, the X-rays or vacuum ultraviolet rays emitted from the X-ray or vacuum ultraviolet ray irradiation device are reflected by the reflecting member, and the reflected light is reflected inside the storage means. Therefore, the separation between the plastic material and the foreign matter is performed efficiently.

According to the eighth aspect of the present invention, when the charged plastic material and the foreign material or the plastic material powder are adhered to each other and irradiated with X-rays or vacuum ultraviolet rays, each of them is neutralized, and is electrically neutralized. The plastic material and the foreign material or the powder of the plastic material are separated from each other, and a purified plastic material can be obtained. A molded product without defects can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an entire injection molding apparatus according to a first embodiment.

FIG. 2 is an enlarged cross-sectional view around a plastic material supply device according to the first embodiment.

FIG. 3 is a longitudinal sectional view of a supply pipe to which an X-ray irradiating apparatus and a foreign matter removing unit according to a second embodiment are attached.

FIG. 4 is a configuration diagram in which a part near a storage tank to which an X-ray irradiating apparatus and a foreign matter removing unit according to a third embodiment are attached is mounted.

FIG. 5 is an enlarged sectional view of a hopper according to a fourth embodiment.

FIG. 6 is a front view of a mechanism for attaching an irradiation device to a hopper according to a fifth embodiment.

FIG. 7 is a front view of a conventional plastic molding injection molding apparatus.

[Explanation of symbols]

 15 Plastic material with foreign substances 16 Plastic material E X-ray

Claims (8)

[Claims] 1. An injection molding method comprising irradiating a charged plastic material with X-rays or vacuum ultraviolet rays and then performing injection molding using the plastic material. 2. The charged plastic material and foreign matter
An injection molding method characterized by irradiating with a line or vacuum ultraviolet rays and performing injection molding using a plastic material from which foreign matter has been removed. 3. The injection molding method according to claim 2, wherein the irradiation of X-rays or vacuum ultraviolet rays and the removal of foreign matter are performed before the supply of the plastic material to the injection cylinder of the injection molding apparatus. 4. An X-ray or vacuum ultraviolet irradiation means for electrically neutralizing a charged plastic material,
And a foreign matter removing means for removing foreign matter from the plastic material electrically neutralized by the X-ray or vacuum ultraviolet irradiation means. 5. A storage means for storing a plastic material, an X-ray or vacuum ultraviolet irradiation means attached to the storage means for electrically neutralizing a charged plastic material, and An injection molding apparatus comprising: a diffusion means for raising and diffusing a plastic material; and a foreign matter removing means attached to the storage means for removing foreign matter from the electrically neutralized plastic material. 6. The injection molding apparatus according to claim 5, wherein said storage means has means for preventing leakage of X-rays or vacuum ultraviolet rays. 7. The injection molding apparatus according to claim 5, wherein said storage means is provided with a reflection member at a position corresponding to an irradiation range of X-rays or vacuum ultraviolet rays. 8. A plastic material is irradiated with X-rays or vacuum ultraviolet rays to separate foreign matter or plastic material powder and plastic material that are electrically attached to the plastic material by neutralizing the foreign matter. A method for cleaning a plastic material, comprising obtaining a plastic material to which no plastic material powder is attached.