JPH10235700A - Injection machine and injection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To rapidly change a material by discharging the material loaded into an almost horizontal and pillar-shaped weighing chamber into a discharge passage with the help of a plunger and at the same time, providing a material supply passage connected to the downstream end of the bottom wall of the weighing chamber. SOLUTION: The first branched passage 133 of a material supply passage 13 is connected to the upper corner part 152 of a columnar weighing chamber 15 set almost horizontally with a center shaft. On the other hand, the downstream end 130 of a second branched passage 134 is connected to the lower corner part 151 of the bottom wall of the weighing chamber 15 by bending the downstream end 130 so that it detours a discharge passage 17. In addition, a center axis passing through the discharge passage 17 and the weighing chamber 15 is straight. The tip face 153 of the weighing chamber 15 is conical and the discharge passage 17 is connected to the apex of the cone. Besides, the outer periphery of a plunger 11 is set in close proximity to the inner periphery of the weighing chamber 15 to such as extent that a resin material does not penetrate in between. The tip face 113 of the plunger 11 is conically shaped to that the tip face 113 coincides with the tip face 153 of the weighing chamber 15, and is connected to the tip part of a rod 114 linked with a piston 115. The resin material is injected into a metal mold from the nozzle 3 of the discharge passage 17.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection machine and an injection method, and more particularly to an injection machine and an injection method for extruding a plasticized resin with a plunger, and a die casting for forming a non-ferrous metal such as aluminum in a molten state. It can also be used for molding and the like.

[0002]

2. Description of the Related Art FIG. 2 is a sectional view of a main part of a conventional injection machine. The resin discharge port (24) of the extruder (2) equipped with the extrusion cylinder (22) and the screw (21) loaded therein is connected to the upstream end of the material supply path (13) of the injection machine (1). Has been
The downstream end (130) of the material supply path (13) is connected to the injection cylinder (1).
2) The upper corner (1) of the inner peripheral wall of the measuring chamber (15) formed in
52) is connected to A plunger (11) is slidably housed in the measuring chamber (15), and the plunger (11) is
A discharge path (17) for injecting a resin material into a mold (not shown) extends from the downstream end of (5).

In this apparatus, when a plasticized resin material is discharged from a resin discharge port (24) of an extruder (2), it is discharged from a downstream end (130) of a material supply path (13) to an injection cylinder (130). It is stored in the measuring chamber (15) of (12), and then the plunger (11) is advanced and the resin material in the measuring chamber (15) is injected into the mold (not shown) from the discharge path (17).

[0004]

However, in the above-described conventional injection machine, the discharge path (17) is required to change the color of the molded product.
When the resin material to be injected from the resin is switched to a different color, there is a problem that the color switching operation cannot be performed quickly. The above problem will be described in more detail.

When the color of a molded article is changed in the above-described conventional apparatus, a resin material of a new color is discharged from the extruder (2), and the resin material is supplied into the material supply path (13) and the measuring chamber (15). Plunger (11) until the remaining original color resin material is gone
And the injection operation is repeated. And the discharge path
When it is confirmed that a resin material of a new color has been discharged from the downstream end of (17), injection molding with the resin material of the color is started thereafter. However, as shown by the imaginary line in the figure, a slight clearance (G) is secured between the distal end surface of the plunger (11) in the most advanced state and the inner surface of the weighing chamber (15) opposed thereto. Have been. At the time of injection plunger (1
This is to prevent the tip of (1) from colliding with the inner surface of the weighing chamber (15) opposed thereto, thereby preventing such damage. Therefore, even if the plunger (11) is advanced, the clearance
The resin of the portion (G) remains in the measuring chamber (15) without being injected. Then, the resin material of the original color remaining in the clearance (G) portion travels along the wall surface of the measuring chamber (15), drips to the lower corner portion (151) at the downstream end thereof, and remains in the portion,
This is not smoothly discharged to the discharge path (17) side. Therefore, even if the resin material of a new color starts being discharged from the discharge path (17), the resin material of the original color remaining in the lower corner portion (151) of the measuring chamber (15) is mixed with the new resin material. Then, the ink is gradually discharged, and the switching to the resin material of a new color cannot be performed quickly.

In the above description, the problem in changing the color has been described. However, the same problem as described above also occurs when the resin material used is changed to one having different characteristics such as melting point and hardness. . The same problem as described above also occurs in the case of performing the die-cast molding in which the molten metal such as aluminum discharged from the extruder (2) is injected by the plunger (11).

The present application has been made in view of the above points,
An object of the present invention is to provide an injection machine that can promptly respond to a change in material. Another object of the present invention is to provide an injection method capable of promptly responding to a change in material.

[0008]

Means for Solving the Problems The technical means of the present invention according to claim 1 employed for solving the above-mentioned problem is that the column-shaped measuring chamber (15) having a central axis set substantially horizontally, Discharge path (17) drawn from the downstream end in the axial direction of the measuring chamber (15)
A plunger (11) for discharging the material in the measuring chamber (15) to the discharge path (17), and a material supply path (13) connected to a downstream end of a bottom wall of the measuring chamber (15). Is provided. "

In the above invention, the material supply path (13) is connected to the measuring chamber (1).
5) It is connected to the downstream end of the bottom wall. Therefore, a new material is supplied to the material supply path (1) at the downstream end of the bottom wall of the measuring chamber (15) where the material that has not been injected toward the discharge path (17) during the previous injection is likely to remain.
Injected from 3). Therefore, the material remaining at the downstream end of the bottom wall of the measuring chamber (15) flows together with new material injected from the material supply passage (13) and diffuses throughout the measuring chamber (15), and thereafter, Then, the liquid is injected toward the discharge path (17) by the plunger (11). That is, according to the above technical means, a new material from the material supply passage (13) is always injected into the downstream end of the bottom wall of the measuring chamber (15), and the old material remains in this portion. Will not be done.

[0010] Claim 3 adopted to solve the above problem.
The technical means of the invention is that the `` injecting step of injecting the material into the measuring chamber (15), and extruding the material in the measuring chamber (15) through a discharge path (17) extending from the measuring chamber (15) An extrusion step, a step of injecting a new material toward the material remaining in the measuring chamber (15) after the extrusion step, and a step of combining the newly injected material and the remaining material together in the discharge path (17). )).

According to the above technical means, a new material is injected toward the material remaining in the measuring chamber (15), and these are diffused together in the entire measuring chamber (15), and then are injected into the discharge path (17). Since the material is extruded, the old material remaining in the measuring chamber (15) is quickly discharged.

[0012]

As described above, according to the first aspect of the present invention, the material which has not been injected toward the discharge path (17) at the time of the previous injection is likely to remain downstream of the bottom wall of the measuring chamber (15). At the end, new material from the material supply path (13) is always injected, and no old material remains in this portion. Therefore, even when the type or color of the material is changed, the material such as the old color before the change is quickly discharged from the measuring chamber (15), and an injection machine can be provided which can quickly respond to the change of the color.

According to the third aspect of the present invention, since the old material remaining in the measuring chamber (15) is quickly discharged, it is possible to provide an injection method capable of promptly responding to switching of colors and the like.

[0014]

Next, an embodiment of the present invention will be described. FIG. 1 is a partial cross-sectional view of a pre-plastic injection molding apparatus in which an injection machine according to an embodiment of the present invention is incorporated. The injection machine (1) to which the present invention is applied and a resin material is supplied thereto. And an extruder (2).

The screw (21) of the extruder (2) is inserted into an extrusion cylinder (22), and the extrusion cylinder (22) is
At the rear end, a rotation driving device (26) for rotating the screw (21) is provided. In addition, the extrusion cylinder (2
2) A hopper (27) for supplying a thermoplastic resin material is continuously provided on the upper surface near the rear end, and the resin material is plasticized on the outer periphery of the extrusion cylinder (22). Heater (2
0) is attached.

A resin discharge port (24) formed at the tip of the extruder (2), that is, at the downstream end, is connected to a material supply passage of the injection machine (1).
It is connected to the upstream end of (13). The material supply path (13) formed in the injection machine (1) has an inclined path (131) connected to the extruder (2) side, a vertical path (132) following the tip thereof, and further, the vertical path (132). First and second branch paths (133) branching from the tip of the vehicle
(134).

The former first branch (133) is connected to an upper corner (152) near the downstream end of a cylindrical measuring chamber (15) having a central axis set substantially horizontally. The measuring chamber (15) is located at the tip of the injection cylinder (12), and a heater (16) is additionally provided on the outer wall surface of the measuring chamber (15). On the other hand, the second branch path (13) in the material supply path (13)
4) is connected to a lower corner portion (151) located at the downstream end of the bottom wall of the weighing chamber (15), and in the middle of the second branch (134), It is curved so as to bypass the linear discharge path (17) drawn out from the downstream end in the axial direction of (15). The central axis of the discharge path (17) and the measuring chamber (15) are aligned in a straight line, and the distal end face (153) on the downstream side of the measuring chamber (15) is formed in a conical shape. The upstream end of the discharge path (17) is connected to the vertex.

A plunger (11) is inserted into the measuring chamber (15), and the outer periphery of the plunger (11) and the inner periphery of the measuring chamber (15) come into close contact with each other to such an extent that the resin material does not enter. ing.
Further, the tip surface (113) of the plunger (11) is formed in a conical shape corresponding to the tip surface (153) of the measuring chamber (15), and the plunger (11) is a piston of a hydraulic cylinder (116).
It is connected to the tip of a rod (114) connected to (115). Further, a nozzle (3) is connected to the downstream end of the discharge path (17) coaxially with the measuring chamber (15).
, A resin material is injected into a mold (not shown).

Next, a cylindrical sliding valve (41) corresponds to a valve port (136) which is a connection between the inclined path (131) of the material supply path (13) and the vertical path (132). , The sliding valve (41), the valve port (13
6) is adjusted, and the valve port (136) is opened and closed. Specifically, the rod (411) connected to the sliding valve (41) is connected to a driving device (412), and the sliding valve (41) is moved forward and backward by the driving device (412). The opening of the valve port (136) is adjusted and the opening / closing is controlled. During the operation of the extruder (2), the valve port (136)
Is adjusted, the pressure in the extruder (2) is adjusted. In addition, the hopper (2
The time required for the resin material supplied from (7) to pass through the extruder (2) changes, thereby adjusting the heating time of the resin material, adjusting the heating time and the pressure in the extruder (2). By the adjustment, the degree of plasticization of the resin material, that is, the viscosity is set to a predetermined value. Also, if the valve port (136) is maintained in the fully closed state by the sliding valve (41), the resin material may flow backward to the extruder (2) during injection (when the plunger (11) advances). Is to be prevented.

Next, the actual operation of the above device will be described.
When the pigment and the non-colored pellet-shaped thermoplastic resin material are put into the hopper (27) and an operation switch (not shown) is turned on, the heater (20) generates heat and the screw (21) rotates, and the hopper (27) The resin material inside is gradually plasticized in the extrusion cylinder (22) by the heat of the heater (20) or the like. The resin material and the above content are uniformly kneaded by the screw (21), whereby the colored resin material is discharged from the resin discharge port (24) of the extruder (2). or,
By setting the opening of the valve port (136) to a predetermined value with the sliding valve (41), the viscosity of the resin material is adjusted as described above, and the resin material adjusted to a viscosity suitable for injection is supplied to the resin discharge port. Discharged from (24).

Next, the resin material discharged from the valve port (136) to the vertical path (132) of the material supply path (13) is supplied to the first branch path (133).
Is branched into the second branch (134) and injected into the measuring chamber (15). That is, the injection step according to the third aspect of the present invention is performed. Then, the plunger (1) at the initial position shown by the imaginary line in FIG.
1) is gradually retracted by the injection pressure of the resin material injected into the measuring chamber (15) from the first and second branch passages (133) and (134). Then, when a predetermined amount of resin material required for injection molding is injected into the measuring chamber (15), the screw (21) stops, and the sliding valve (41) is moved downward by the driving device (412). Valve
(136) is kept closed. Next, the hydraulic cylinder (1
The plunger (11) is advanced by operating (16), whereby the plasticized resin material stored in the measuring chamber (15) is not shown through the discharge path (17) and the nozzle (3). Injected into the mold. That is, the extrusion step according to the third aspect of the present invention is performed.

Next, the operation of switching the color of the resin material to be injection molded will be described. When switching the color of the resin material to be injection-molded, change the pigment charged into the hopper (27) to a new color, and then change the resin material discharged from the nozzle (3) to the new color. Repeat the injection operation until it changes to. In this case, the second branch passage (1) is formed in the lower corner portion (151) of the measuring chamber (15) where the resin material not injected into the discharge passage (17) during the previous injection remains.
34) is connected, and when the above-described injection operation is repeated to switch the color of the resin material, when the resin material of a new color starts to be discharged into the measuring chamber (15), the second branch path (1)
The resin material of a new color discharged from the downstream end (130) of (34) is a lower corner (151) at the tip of the measuring chamber (15), that is,
The resin material of the old color is discharged from the lower corner portion (151) where it is likely to remain (corresponding to the "step of injecting a new material toward the remaining material" of the invention of claim 3). That is, the resin material of the old color remaining in the lower corner portion (151) (the resin material that was not injected toward the discharge path (17) during the previous injection operation) is discharged from the second branch path (134). Is diffused throughout the measuring chamber (15) with the new color resin material,
This is injected into the mold from the discharge path (17) and the nozzle (3) ("the step of extruding into the discharge path (17)" of the invention of claim 3).
Corresponding to ). Therefore, the resin material of the old color is quickly injected into the lower corner portion (151), and the color of the resin material can be switched smoothly and quickly.

In the above embodiment, the uncolored resin material and the pigment are supplied from the hopper (27). However, a colored pellet-shaped thermoplastic resin material may be supplied from the hopper (27). Further, a conductive material, carbon fiber, stainless fiber, glass fiber, or the like may be mixed with these resin materials. Further, in the above-described embodiment, the metering-type volume molding in which the material is measured in the measuring chamber (15) is used. Therefore, when a foaming agent or the like is added, the heating time is adjusted while the foaming agent or the like is uniformly kneaded with the resin material in the extruder (2) by adjusting the opening of the valve port (136). Foaming (gas foaming / chemical foaming) where the material whose viscosity has been adjusted by pressure adjustment (by the sliding valve (41)) in the machine (2) is foamed and melted and guided to the measuring chamber (15) and injected. The invention of the present application can be applied to the case of soybean cake residual foaming.

Further, in the above embodiment, the case where the resin material is injection-molded has been described. However, a non-ferrous metal such as aluminum is melted by the extruder (2), and the molten metal is guided to the measuring chamber (15) for injection. The invention of the present application can be applied to the case where die casting is performed. In the above embodiment, the first and second return routes (133) branched off from the middle of the material supply path (13).
(134) are connected to the measuring chamber (15), but only the lower second return path (134) may be connected to the measuring chamber (15).

Further, the central axis of the measuring chamber (15) may be slightly inclined so as to become lower toward the discharge path (17). When a concave portion or the like in which the material is likely to remain is formed on the inner peripheral wall of 15), a new material from the material supply path (13) may be injected into this portion. This is because the old material remaining in the concave portion is diffused throughout the measuring chamber (15) together with the new material from the material supply path (13). Further, in the case of the method invention of claim 3, the measuring chamber (1
The inclination angle of the central axis in 5) is not limited to the horizontal. Further, the central axis of the measuring chamber (15) may be slightly inclined so as to be higher toward the discharge path (17). Also in this case, when the plunger (11) is pushed out, the material hangs down on the downstream end of the bottom wall of the measuring chamber (15) and remains in this portion.

[Brief description of the drawings]

FIG. 1 is a partially cutaway sectional view of a pre-plastic injection device including an injection machine according to an embodiment of the present invention.

FIG. 2 is an explanatory view of a conventional example.

[Explanation of symbols]

 (1) ・ ・ ・ Injection machine (2) ・ ・ ・ Extruder (11) ・ ・ ・ Plunger (13) ・ ・ ・ Material supply path (15) ・ ・ ・ Measuring chamber (17) ・ ・ ・ Discharge path

Claims (3)

[Claims] 1. A column-shaped measuring chamber (15) having a central axis set substantially horizontally, a discharge path (17) drawn out from an axially downstream end of the measuring chamber (15), and the measuring chamber. (15) a plunger (11) for discharging the material in the discharge path (17), and a material supply path (13) connected to a downstream end of a bottom wall of the measuring chamber (15).
An injection machine comprising: 2. The injection machine according to claim 1, wherein said material is a thermoplastic resin material. 3. An injecting step of injecting a material into the measuring chamber (15); an extruding step of extruding the material in the measuring chamber (15) through a discharge path (17) extending from the measuring chamber (15); A step of injecting a new material toward the material remaining in the measuring chamber (15) after the extrusion step, and a step of extruding the newly injected material and the remaining material together into the discharge path (17). An injection method comprising: