JP6436454B2 - Molten material supply equipment - Google Patents

Description

According to the present invention, a screw is disposed in a heating cylinder so that the screw can rotate and move forward and backward, and a nozzle is disposed in a front part of the heating cylinder, and a resin material including a fiber material is plasticized in the heating cylinder and injected from the nozzle. Or it is related with the molten material supply apparatus to discharge.

A screw is arranged in the heating cylinder so that it can rotate and move forward and backward, and a nozzle is arranged in the front part of the heating cylinder, and a resin material containing a fiber material is plasticized in the heating cylinder and injected or discharged from the nozzle. When a molded product is molded using the material supply device, a molded product having a desired strength cannot be obtained unless the fiber material having a sufficient length remains in the molded product at a certain ratio or more. Moreover, a molded article having a desired strength cannot be obtained unless the fiber material is well dispersed in the resin.

The reason why the fiber material is cut when the resin material containing the fiber material is plasticized in the heating cylinder and injected or discharged to form a molded product is that the fiber material is subjected to a certain level of stress during plasticization or injection. It is conceivable that the fiber material is cut due to the crack. For this reason, conventionally, measures have been taken such as reducing the screw rotation speed during plasticization to a certain level or less, or not increasing the injection speed during injection. Also, if there is a narrow part in the screw or nozzle in the heating cylinder, the sprue and runner in the mold, or the cavity, the melted material containing the fiber material generates stress when it passes through the narrow part. May lead to disconnection.

Therefore, as a result of various verifications by the applicant of the present application, when the resin material containing the fiber material is injection-molded, the cross-sectional area of the narrowest channel in the portion of the backflow prevention valve of the screw is the cut of the fiber material. It came to know that it has influenced.

2. Description of the Related Art Conventionally, in a molten material supply apparatus, what is described in Patent Document 1 is known as a description of the cross-sectional area of the resin flow path of the check valve portion. Patent document 1 has two backflow prevention valves in a center part and a front-end | tip part. And even if pellet raw material that is not completely melted in the molten resin is mixed in the resin raw material, the central part backflow prevention valve is better than the backflow prevention valve at the tip so that it can pass smoothly. The cross-sectional area of the resin flow path 53 through which the molten resin material passes is set wide.

That is, the cross-sectional area of the resin flow path 53 (see FIG. 2a) in the central backflow prevention valve is 107.0 mm ² , and the cross-sectional area in the direction orthogonal to the axial direction of the screw 22 (the cross-sectional area of the inner hole of the heating cylinder). Substantially equivalent) to 17.4% of 615.4 mm ² (π14 ² ). However, the cross-sectional area of Patent Document 1 is a cross-sectional area of a portion orthogonal to the axial direction between the small-diameter portion of the screw shaft portion D2 and the backflow prevention valve D3, and is between the shaft portion of the screw and the backflow prevention valve. Whether or not the cross-sectional area of the narrowest channel is not certain. Moreover, in patent document 1, the relationship between the cross-sectional area of the resin flow path 53 of a backflow prevention valve and the cross-sectional area of the groove part of a screw is not described.

Moreover, what was described in patent document 2 is known as what prescribes | regulates the cross-sectional area of a backflow prevention valve with the cross-sectional area of the flow path of a screw. In Patent Document 2, the ratio between the cross-sectional area of the backflow prevention valve and the cross-sectional area of the molten resin passage cut in the direction perpendicular to the flight in the screw metering zone is in the range of 1.0 to 2.0. It is described as being good. When the ratio of the cross-sectional area is smaller than 1.0, it is described that the discharge pressure increases and the plasticizing ability decreases, or the temperature of the molten resin rises and a predetermined resin temperature cannot be obtained. ing. Further, when the ratio of the cross-sectional area is larger than 2.0, the temperature of the molten resin becomes non-uniform, and in some cases, the molten resin becomes unmelted, and the kneadability and temperature unevenness of the molten resin are likely to occur. Have been described. However, Patent Document 2 does not describe the relationship between the cross-sectional area of the resin flow path of the check valve and the cross-sectional area of the groove of the feed zone of the screw.

In a screw of an injection device of a general injection molding machine, the cross-sectional area of the narrowest channel of the backflow prevention valve is set to be smaller than the cross-sectional area of the groove portion of the screw feed zone. And the cross-sectional area of the flow path of the narrowest part of the backflow prevention valve is set to about 6% to 10% of the cross-sectional area of the inner hole of the heating cylinder. The lower limit value of the narrowest portion of the backflow prevention valve is such that if the cross section of the narrowest portion of the backflow prevention valve is narrower than this, the plasticizing ability is lowered and the temperature of the molten resin is increased. A numerical value has been selected. On the other hand, for the upper limit value, such a value is often selected from the strength and durability of the check valve. That is, in order to increase the cross-sectional area of the narrowest part of the backflow prevention valve, it is necessary to reduce the thickness of the ring part or the diameter of the shaft part. It is thought that it falls. Therefore, conventionally, no attempt has been made to actively increase the cross-sectional area of the narrowest portion of the check valve.

JP 2012-51268 A (0032, 0034, 0035, FIG. 2) JP 2010-247432 A (Claims 1, 0024, 0028, FIG. 1)

Since Patent Document 1 plasticizes a material obtained by adding a chemical foaming agent to a thermoplastic resin, even if there is a narrow portion in the flow path of the backflow prevention valve, the flow of the backflow prevention valve is not limited as long as the resin is in a molten state. The cross-sectional area of the road was not a big problem. For this reason, in Patent Document 1, it can be said that the cross-sectional area of the flow path of the check valve in the above-described range remains. However, when plasticizing a resin material containing a fiber material using a screw equipped with a check valve of Patent Document 1, it is presumed that cutting of the fiber material cannot be reduced sufficiently. As a result, it is presumed that a desired strength cannot be obtained even for a molded product formed by using a molten resin obtained by cutting a fiber material at a certain level or more.

Further, Patent Document 2 does not mention the cross-sectional area of the flow path at the narrowest part of the check valve, and does not mention plasticization of a resin material including a fiber material. In addition, in the case of a screw of an injection device of a general injection molding machine, the backflow prevention valve portion is not designed to be optimal for plasticizing resin materials including fiber materials, and has a structure that emphasizes durability. It has become.

Therefore, in view of the above problems, the present invention has an object to provide a molten material supply device capable of reducing the cutting of the fiber material, particularly when the resin material containing the fiber material is plasticized in the heating cylinder. To do.

The molten material supply apparatus according to claim 1 of the present invention is a thermoplastic resin material in which a screw is disposed in a heating cylinder so as to be rotatable and can be moved forward and backward, and a nozzle is disposed in front of the heating cylinder, and includes a fiber material. in the molten material supply device for emitting or discharging from the nozzle and plasticized in the heating cylinder, said screw, the screw rear end face and rear end face of the ring portion of the check valve is abutting upon retraction The cross-sectional area of the narrowest channel excluding the channel between the two parts is formed wider than the cross-sectional area of the groove of the feed zone of the screw, and the flow of the narrowest part of the check valve is cut off. The area is formed to be 25% to 35% with respect to the cross-sectional area of the inner hole of the heating cylinder.

The molten material supply apparatus according to claim 2 of the present invention is a thermoplastic resin material in which a screw is disposed in a heating cylinder so as to be rotatable and can be moved forward and backward, a nozzle is disposed in a front portion of the heating cylinder, and includes a fiber material. In the molten material supply apparatus for plasticizing in the heating cylinder and injecting or discharging from the nozzle, the groove depth of the screw feed zone is 10.5 to 16.1% of the screw diameter, sectional area of the flow path of the narrowest portion excluding the flow path groove of the feed zone of the screw between the scan crus portion rear end face and rear end face of the ring portion of the valve is brought into contact when retracted The cross-sectional area of the flow path at the narrowest part of the check valve is 300% to 500% of the cross-sectional area of the groove of the screw metering zone. Features.

According to a third aspect of the present invention, there is provided the molten material supply device according to the first or second aspect, wherein the head portion of the screw head provided on the front side of the backflow prevention valve is in contact with the backflow prevention valve. 2 to 6 blade portions that are tapered from the contact portion toward the tip of the head portion.

In the molten material supply device of the present invention, a screw is disposed in a heating cylinder so that the screw can rotate and move forward and backward, and a nozzle is disposed in a front part of the heating cylinder, and a thermoplastic resin material including a fiber material is disposed in the heating cylinder. in the molten material supply device for emitting or discharging from the nozzle plasticized, the screw, the flow between the portion of the screw rear end face and rear end face of the ring portion of the check valve is brought into contact when retracted The cross-sectional area of the narrowest channel excluding the channel is formed wider than the cross-sectional area of the groove of the screw feed zone, and the cross-sectional area of the narrowest channel of the backflow prevention valve is Since it is formed at 25% to 35% with respect to the cross-sectional area of the inner hole, cutting of the fiber material during plasticization can be reduced.

It is sectional drawing of the injection apparatus of one Embodiment of the molten material supply apparatus of this invention. It is an expanded sectional view of the screw of one embodiment of the molten material supply device of the present invention. It is a front view of the screw of one embodiment of the molten material supply device of the present invention.

An injection apparatus 12 according to an embodiment of the molten material supply apparatus of the present invention will be described with reference to FIG. In the injection device 12 of the injection molding machine 11, a screw 22 is disposed in the inner hole 16 a of the heating cylinder 16 so as to be rotatable and can be moved forward and backward, and a nozzle 15 is disposed in front of the heating cylinder 16. The injection device 12 plasticizes the resin material M including the fiber material in the heating cylinder 16 and injects it from the nozzle 15. The injection molding machine 11 is provided with a mold clamping device 13 in front of the injection device 12, and the nozzle 15 is touched to a mold 14 (fixed mold) attached to the mold clamping device 13. As for the injection device 12, a housing portion 17 is provided in the vicinity of the rear portion of the heating cylinder 16, and a material supply hole 18 and a supply device 19 are provided in the housing portion 17. The heating cylinder 16 is provided with an inner hole 16a in the axial direction, and a heater 20 capable of controlling the temperature for each zone is provided on the outer periphery. A cylinder head portion 21 is fixed to the front portion of the heating cylinder 16. The inner side surface 21 a of the cylinder head portion 21 is tapered, the rear large diameter portion is connected to the inner hole 16 a of the heating cylinder 16, and the front small diameter portion is connected to the nozzle hole 15 a of the nozzle 15. Yes. In the present invention, the cylinder head portion 21 is also referred to as a heating cylinder, and the hollow portion inside thereof is referred to as a heating cylinder. Moreover, the heating cylinder 16 calls the nozzle 15 side the front, and calls the housing part 17 side the back.

The screw 22 is rotatably provided by a metering motor (not shown), and is provided so as to be movable forward and backward by an injection motor (not shown). The shape of the screw 22 is such that, from the rear, the feed zone 23 with a constant cross-sectional area D2 of the groove part, the compression zone 24 in which the shaft part is gradually thickened and the groove part is gradually shallow, and the cross-sectional area D3 of the groove part is constant. A ring zone 25 is formed. The flights 22a of the screw 22 are formed at the same pitch in each of the zones 23, 24, and 25. The compression ratio of the screw 22 is not limited to this, but is preferably 1.0 to 3.0, more preferably 1.2 to 2.2, and the compression ratio is relatively low. The generation of force is made as small as possible to prevent cutting when using a fiber material as much as possible. Further, the screw 22 may have another flight such as a subflight, or may be provided with a mixing zone in which fine irregularities are formed. The inner hole 16a and the screw 22 of the heating cylinder 16 are preferably subjected to wear resistance processing, particularly when a resin containing glass fiber or the like is used as a molding material. Furthermore, the heating cylinder 16 is configured such that the inside of the inner hole 16a can be vacuum-sucked by a vacuum pump from the material supply hole 18 or the vicinity of the middle of the heating cylinder 16, or nitrogen gas is supplied into the inner hole 16a. But you can.

Further, in the screw 22 having a diameter of 90 mm according to the present embodiment, the cross-sectional area D2 of the flow path of the groove portion of the feed zone 23 of the screw 22 (the area of the surface in the direction perpendicular to the direction of the flight 22a as shown in FIG. 1) 8.8 cm ² . By using the screw 22 that secures the flow path area of the groove portion of the feed zone 23 as described above, it is possible to reduce the cutting of the fiber material such as glass fiber or carbon fiber in the feed zone 23 of the heating cylinder 16. In the case of the screw 22 having a diameter of 90 mm according to the present embodiment, the groove depth of the feed zone 23 is desirably about 9.5 to 14.5 mm. The groove depth of the feed zone 23 differs depending on the screw diameter and is not limited to this, but it is preferably about 10.5% to 16.1% of the diameter of the screw 22 as an example.

In the present embodiment, the groove depth H of the metal ring zone 25 of the screw 22 is deeper than that of a normal screw. In other words, the diameter of the shaft portion 25a of the metering zone 25 is smaller than that of a normal screw. In the case of a general screw having a diameter of 90 mm, the groove depth of the metering zone 25 is about 4.5 to 5 mm, but in this embodiment, the groove depth H is deeper than that. The groove depth H of the metal ring zone differs depending on the screw diameter and is not limited to this, but in this embodiment, it is preferably about 6% to 10.5% of the diameter of the screw 22 as an example.

As shown in FIG. 2, the cross-sectional area D3 of the flow path of the groove portion of the metering zone 25 of the screw 22 having a diameter of 90 mm according to this embodiment (the surface in the direction orthogonal to the direction of the flight 22a as shown in FIG. 2). The area) is 4.9 cm ² , which is about 1.5 times that of a general screw. In this way, by using the screw 22 that secures the groove depth and the flow path area of the metering zone 25, the fiber material such as glass fiber or carbon fiber can be used as the inner hole 16 a of the heating cylinder 16 and the metering zone 25 of the screw 22. It is possible to reduce short cutting due to the shearing action between the two.

A disc-shaped wear plate 33 is provided at the front of the metering zone 25 of the screw 22. The wear plate 33 is a portion that comes into contact when the rear end surface 35a of the ring portion 35 of the check valve 26 is retracted. In the present embodiment, the outer diameter of the wear plate 33 is provided to be the same as the diameter of the shaft portion 25 a of the metering zone 25. The diameter of the wear plate 33 does not have to be the same as the diameter of the shaft portion 25a of the metering zone 25. However, as an example, the diameter of the wear plate 33 is desirably about −4 mm to +4 mm than the diameter of the shaft portion 25 a of the metering zone 25.

2 and 3, the shaft portion 34 of the screw head 27 is inserted into the center portion of the front portion of the wear plate 33, and is screwed and fixed to the screw body. The rear end side of the shaft portion 34 is a large-diameter portion 34a having a large shaft diameter, and a ring-facing portion 34b having a thin shaft diameter is provided so that the diameter smoothly decreases toward the front. A hollow ring portion 35 of the backflow prevention valve 26 is attached to the outer periphery of the ring facing portion 34b with a predetermined interval. Two blade portions 36 are formed in a radial direction from the shaft core O in the head portion 34 c further forward of the ring facing portion 34 b of the shaft portion 34. A portion of the rear end surface 36a of each blade portion 36 close to the inner hole 16a of the heating cylinder 16 is brought into contact with the front end surface 35b of the ring portion 35. More specifically, a portion on the outer peripheral side (a portion on the inner hole 16 a side) of the rear end surface 36 a of the blade portion 36 in the radial direction is a contact surface with the ring portion 35. In this way, the outer peripheral portion of the rear end surface 36 a of the blade portion 36 abuts on the ring portion 35, so that a wide flow path is secured between the ring portion 35 and the shaft portion 34.

In the present embodiment, the blade portion 36 is tapered toward the tip of the screw head 27 in correspondence with the tapered surface of the recess 29 at the rear portion of the torpedo 28. That is, the blade portion 36 has a triangular shape with the most acute angle on the most distal side of the screw head 27 as viewed from the side. And as FIG. 3 shows, the part which does not have the blade | wing part 36 of the head part 34c is provided with the same diameter as the ring opposing part 34b. The flow path of the check valve 26 is connected to the ring outlet flow path D6 between the front head section 34c and the ring section 35 from the ring internal flow path D4 between the ring facing section 34b and the ring section 25. . The ring outlet side channel 35 has a narrower cross-sectional area than the ring internal channel D4 because the blade portion 36 has no channel.

A portion of the head portion 34c of the screw head 27 other than the blade portion 36 has the same diameter as the ring facing portion 34b. The front end portion of the head portion 34c is a conical portion 34d having a tapered diameter. The inclination angle of the conical part 34d is the same as the inclination angle of the blades of the blade part 36. The shaft diameter of the head portion 34c of the screw head 27 may be increased or reduced in diameter within a certain range toward the front. In this embodiment, the large diameter portion 34 a of the shaft portion 34 of the screw head 27, the ring facing portion 34 b, and the blade portion 36 constitute a part of the backflow prevention valve 26. However, a conical screw head may be provided by a separate member from the backflow prevention valve 26.

As described above, the blade portion 36 serves to lock the forward movement of the ring portion 35 of the backflow prevention valve 26 and rotates as a part of the screw head 27 during plasticization to be stored in front of the screw 22. It also has a role of kneading molten resin containing the fiber material to be produced. It is desirable that two to six blade portions 36 are formed on the screw head 27. About the width | variety (thickness) of the blade | wing part 36, about 5 to 25% of the diameter of the screw 22 is desirable as an example. However, according to the present invention, if the cross-sectional area of the narrowest channel of the backflow prevention valve 26 is ensured, the blade portion 36 as described above is not formed in the screw head 27 but another kneading element is formed. Or a general conical screw head having no kneading element may be provided.

As shown in FIGS. 1 to 3, a backflow prevention valve 26 is provided at the front portion of the screw 22. The backflow prevention valve 26 is essential in the present invention in order to prevent the molten material stored on the front side of the heating cylinder 16 during the injection from moving to the rear of the screw 22 and the injection amount becoming unstable. The hollow ring portion 35 that forms the backflow prevention valve 26 has an outer diameter that is inserted into the inner hole 16a of the heating cylinder 16 without a gap. It is formed to have a dimension that faces the ring internal channel D4 between the ring facing part 34b. In the present embodiment, a donut-shaped ring internal flow path D4 having a width of 12 mm is formed in the radial direction from the axis O of the shaft portion 34. The ring portion 35 is inserted between the front end surface 33a of the wear plate 33 and the rear end surface 36a of the blade portion 36 so as to be movable in the axial direction X of the screw 22 by a predetermined stroke S. In other words, the length in the axial direction X of the ring portion 35 is shorter by a predetermined length than the distance between the front end surface 33a of the wear plate 33 and the rear end surface 36a of the blade portion 36, and the difference between them is The movement stroke S of the ring portion 35 is obtained. The stroke S is not limited to this in order to widen the cross-sectional area of the narrowest portion of the backflow prevention valve 26, which will be described later. However, as an example, the stroke S is 12.0 with respect to the diameter D of the screw 22. It is desirable to set the stroke S between% and 16.0%.

Further, as shown in FIG. 3, the front end surface 35a of the ring portion 35 is formed with two engaging protrusions 35c for preventing the rotation of the ring portion 35 so as to sandwich both sides of the blade portion 36. Has been. In the present invention, the screw 22 includes all of the ring portion 35 and the screw head 27 of the backflow prevention valve 26. The wear plate 33, the ring portion 35, and the blade portion 36 of the screw head 27 are preferably manufactured using a special alloy, or subjected to a surface hardening process or a wear-resistant process on a steel or special alloy material.

Further, in the present embodiment, as shown in FIG. 2, the large diameter portion 34 a on the rear end side of the shaft portion 34 of the screw head 27 and the inner peripheral side end of the rear end surface 35 a of the ring portion 35 of the backflow prevention valve 26. The ring inlet channel D5 in between is the narrowest channel of the check valve 26. In this embodiment, the ring inlet channel D5 has a cross-sectional area (doughnut-shaped cross-sectional area) of 18.0 cm ^2, and a cross-sectional area D1 of the inner hole 16a of the heating cylinder 16 (in a direction perpendicular to the screw axis). The area corresponds to a ratio of 28.3% with respect to the cross-sectional area (about 63.6 cm ² when the diameter is 90 mm). Therefore, compared with a general screw backflow prevention valve, the flow resistance when the molten resin and the fiber material pass through the narrowest portion during plasticization can be greatly reduced. The flow path at the narrowest portion of the backflow prevention valve 26 of this embodiment is not a surface orthogonal to the axial direction X of the screw 22 but a donut-shaped surface protruding toward the outer periphery. However, the angle of the cross section of the narrowest channel is not limited by the shape of the backflow prevention valve 26.

The thickness of the ring portion 35 of the check valve 26 cannot be made thinner than 10 mm in the case of the screw 22 having a diameter of 90 mm because of the cylindrical tensile stress. Therefore, the diameter on the inner peripheral side of the ring portion 35 cannot be made larger than 70 mm. Further, the diameter of the shaft portion 34 of the screw head 27 cannot be made smaller than a certain value due to the torsional stress. Therefore, the cross-sectional area of the shaft part 34, the ring part 35, and the narrowest part cannot be larger than 50% of the cross-sectional area D1 of the inner hole 16a of the heating cylinder 16 (the cross-sectional area in the direction perpendicular to the screw axis). From the above limitation, in the screw 22 of the present invention, the cross-sectional area of the narrowest channel of the backflow prevention valve 26 is preferably 20% to 50% with respect to the cross-sectional area D1 of the inner hole 16a of the heating cylinder 16. More preferably, the cross-sectional area of the narrowest channel of the backflow prevention valve 26 is more preferably 25% to 35%, more preferably the ring portion 35. This is because if the thickness is made thinner or the diameter of the shaft portion 34 of the screw head 27 is made smaller, the durable life of the check valve 26 may be shortened. Cross-sectional area is backflow prevention It is determined from consideration of the degree of breakage of the durability and fibrous materials of the valve 26.

In the present invention, the narrowest channel of the check valve 26 is the ring inlet channel D5. Depending on the structure of the check valve 26, the ring inner channel D4 and the ring outlet channel may be used. It is also assumed that D6 is the narrowest channel. For the backflow prevention valve 26, if the cross-sectional area of the narrowest part can be secured within a range of 20 to 50% of the cross-sectional area D1 of the inner hole 16a of the heating cylinder 16, the inside of the screw A ball check type backflow prevention valve in which a flow path is formed in the flow path and a ball capable of moving back and forth is disposed in the flow path may be used.

And the cross-sectional area D5 of the flow path of the narrowest part of the backflow prevention valve 26 is provided wider than the cross-sectional area D2 of the groove part of the feed zone 23 of the screw 22. The cross-sectional area D5 is wider than the cross-sectional area D2 of the groove portion of the feed zone 23 of the screw 22, and the upper limit is desirably formed to an area of 200% or less as an example. The cross-sectional area D5 of the narrowest channel of the backflow prevention valve 26 is preferably 300% to 500% of the cross-sectional area D3 of the groove portion of the metering zone 25 of the screw 22. Thus, by providing the cross-sectional area D5 of the flow path of the narrowest part of the backflow prevention valve 26, a state in which the stress is reduced when the molten resin containing glass fiber passes through the part of the backflow prevention valve 26. In order to prevent fiber breakage.

A torpedo 28 is provided in the heating cylinder 16 at a position further forward than the position where the screw 22 has moved to the maximum forward side (forward limit). In the torpedo 28, the diameter of the outer peripheral portion 30 is smaller than the inner hole of the heating cylinder 16, and the cross-sectional area of the flow path in the heating cylinder 16 is narrow at the portion where the torpedo 28 is provided. The torpedo 28 has a cylindrical shape on the outside, and is fixed with the longitudinal direction in the axial direction of the heating cylinder 16. The method of attaching the torpedo 28 is fixedly supported in the heating cylinder 22 by a plurality of support portions (not shown) formed from the inner hole 16a side of the heating cylinder 16 toward the shaft core side. The torpedo 28 is formed with a tapered recess 29 on the rear side facing the screw head 27 at the tip of the screw 22. An internal flow path 31 a is formed in the torpedo 28 in communication with the recess 29.

An outer peripheral flow path 31b is formed between the outer peripheral portion 30 of the torpedo 28 and the inner hole 16a of the heating cylinder 16 (including the inside of the concave portion 21a of the cylinder head portion 21). The outer peripheral flow path 31b is formed on the entire circumference from the rear to the front of the torpedo 28 except for the support portion. Therefore, the inner flow path 31a and the outer peripheral flow path 31b are provided in parallel in the part behind the center of the torpedo 28 in the front-rear direction. The cylindrical portion 30a on the outer periphery of the torpedo 28 and a conical portion 30b in front of the torpedo 28 are each formed with a plurality of protruding portions 32 that protrude. In addition, the internal flow path 31a and the convex part 32 of the torpedo 28 are not essential, respectively, and a general torpedo shaped torpedo 28 may be used. The torpedo 28 may be provided in the nozzle 15. Furthermore, in the present invention, the torpedo 28 is not essential and can be omitted.

Next, the plasticizing process and the injection process using the injection apparatus 12 which is the molten material supply apparatus of this embodiment will be described. The material M used in the present embodiment is a glass fiber (fiber material) and a thermoplastic resin pellet (resin material) supplied separately. The length of the glass fiber at the time of supply is 4 mm to 10 mm. However, the thermoplastic resin pellet itself may contain glass fibers. The fiber material and the resin material may be supplied from separate material supply holes. On the other hand, the temperature of each zone of the heating cylinder 16 of the injection device 12 is set within the range of the set temperature range of the general heating cylinder 16 set corresponding to each type of thermoplastic resin. The material M made of glass fiber and thermoplastic resin pellets supplied from the supply device 19 through the material supply hole 18 into the heating cylinder 16 starts the plasticizing process and operates a metering motor (not shown). The screw 22 is rotated and fed forward in the order of the feed zone 23, the compression zone 24, and the metering zone 25, and the melting proceeds. The thermoplastic resin pellets are almost completely melted in the metal ring zone 25, and the ring inlet channel D5 (the narrowest part of the narrowest part) of the backflow prevention valve 26 in which the ring part 35 is moved to the front contact part 36a. Flow path), the ring internal flow path D4, and the ring exit flow path D6.

Rotational speed of the screw 22 by metering motor in this case, it is desirable also affected by the diameter of the screw 22 is a 20min ^-1 ~150min ^-1 as an example. The back pressure controlled by the injection motor or the injection hydraulic cylinder is desirably controlled to 0 MPa to 10.0 MPa as an example. And since the groove depth H of the metal ring zone 25 of the screw 22 is provided deeper than a general screw in the range described in the paragraph number (0021), the cutting of the fiber material in the metal ring zone 25 is reduced. To do. In the present invention, the screw 22 is provided such that the cross-sectional area of the ring inlet flow path D5, which is the narrowest flow path of the check valve 26, is larger than the cross-sectional area D2 of the groove portion of the feed zone 23 of the screw 22. Since the cross-sectional area D1 of the inner hole 16a of the heating cylinder 16 is 20% to 50% of the cross-sectional area D1, the flow resistance at the portion of the backflow prevention valve 26 is compared with that of the conventional backflow prevention valve. Decreases and the glass fiber is cut less. Further, since the cross-sectional area of the narrowest channel is formed to be 300% to 500% of the cross-sectional area D3 of the groove portion of the metering zone 25 of the screw 22, the backflow prevention valve 26 in front of the metering zone 25 is formed. The pressure is released even when the molten resin is sent to the narrowest part. And even if the feed direction of the molten resin containing the glass fiber which has advanced between flights is changed, it will reduce that a glass fiber is cut | disconnected.

Moreover, since the molten resin containing the glass fiber that has passed through the backflow prevention valve 26 is agitated with the screw rotation by the blade portion 36 provided in the shaft portion 34, the mixing of the glass fiber and the molten resin is further improved. . In the plasticizing step, the screw 22 is driven to rotate and the screw 22 is retracted, and the distance between the concave 29 side of the torpedo 28 and the screw head 27 of the screw 22 is widened. Molten material) is stored in that part. When the plasticizing process is completed, the injection device 12 waits until the molded product in the mold 14 is taken out and is clamped again. Note that the backflow prevention valve 26 may be intentionally closed by reversely rotating or advancing the screw 22 after the latter half or the end of the plasticizing step. Next, when the injection process is started, the injection device 12 operates the injection motor to advance the screw 22 as an example at an injection speed (maximum speed) of 15 mm / sec to 120 mm / sec. As a result, the molten resin passes through the flow passage portion of the torpedo 28 in the heating cylinder 16 and is injected from the nozzle 15 into the mold 14. At this time, the ring portion 35 of the backflow prevention valve 26 moves rearward and the rear end surface 35a comes into contact with the wear plate 33 to block the flow of the molten resin from the screw head 27 side to the flight 22a side. Make the amount constant.

At the time of injection, the molten resin contained in the glass fiber is sent forward in parallel from the internal flow path 31a and the outer peripheral flow path 31b of the torpedo 28. Since the internal flow path 31a is connected to the outer peripheral flow path 31b at a substantially central portion in the front-rear direction of the torpedo 28, the molten resin sent from the internal flow path 31a and the outer peripheral flow path 3 is merged and mixed. Is done. In addition, since the plurality of convex portions 32 are formed on the cylindrical portion 30a and the conical portion 30b of the torpedo 28, mixing of the molten resin contained in the glass fiber is performed more satisfactorily at the time of injection.

The present invention is not enumerated one by one, but is not limited to that of the above-described embodiment, and it goes without saying that those skilled in the art also apply modifications made in accordance with the spirit of the present invention. is there. The material melted by the injection apparatus is a mixture of a thermoplastic or thermosetting resin and a fiber material such as carbon fiber or glass fiber, but the combination and ratio thereof are not limited.

Furthermore, the molten material supply device of the present invention may be a stamping-molded molten material supply device that discharges molten resin containing measured fibers from a nozzle (including a T die) onto a press die. In addition, the molten material supply device of the present invention may be used for a plasticizing device portion of a pre-plastic (registered trademark) type injection device to which a plasticizing device and a plunger device are respectively connected.

DESCRIPTION OF SYMBOLS 11 Injection molding machine 12 Injection apparatus 15 Nozzle 16 Heating cylinder 16a Inner hole 22 Screw 23 Feed zone 24 Compression zone 25 Metalling zone 26 Backflow prevention valve 27 Screw head 28 Torpedo 34 Shaft part 35 Ring part 36 Blade part D1 Inner hole Cross-sectional area D2 Cross-sectional area D3 of feed zone groove section Cross-sectional area D5 of metering zone groove section D5 Ring inlet channel

Claims (3)

A screw is arranged in the heating cylinder so that it can rotate and move forward and backward, and a nozzle is arranged in the front part of the heating cylinder, and a thermoplastic resin material containing a fiber material is plasticized in the heating cylinder and injected or discharged from the nozzle. In the molten material supply device
The screw, the screw is a cross-sectional area of the flow path of the narrowest portion excluding the flow path between the portion of the scan Cru rear end face and rear end face of the ring portion of the check valve is brought into contact when retracted Is formed wider than the cross-sectional area of the groove of the feed zone,
The molten material supply apparatus, wherein the cross-sectional area of the flow path at the narrowest part of the backflow prevention valve is 25% to 35% with respect to the cross-sectional area of the inner hole of the heating cylinder. A screw is arranged in the heating cylinder so that it can rotate and move forward and backward, and a nozzle is arranged in the front part of the heating cylinder, and a thermoplastic resin material containing a fiber material is plasticized in the heating cylinder and injected or discharged from the nozzle. In the molten material supply device
The groove depth of the screw feed zone is 10.5 to 16.1% of the diameter of the screw, and the screw that comes into contact when the rear end surface of the ring portion of the check valve and the rear end surface are retracted. of being wider than the cross-sectional area of the groove of the feed zone of the cross-sectional area is the screw of the flow path of the narrowest portion excluding the flow path between the section component,
The molten material supply apparatus according to claim 1, wherein a cross-sectional area of a flow path at a narrowest portion of the backflow prevention valve is formed to be 300% to 500% of a cross-sectional area of a groove portion of a screw metering zone. The head portion of the screw head provided on the front side of the backflow prevention valve has a contact portion with which the backflow prevention valve abuts, and a blade portion that is tapered from the contact portion toward the tip of the head portion. The molten material supply apparatus according to claim 1, wherein two or six of the molten material are provided.