JP2007245594A - Online-blend type injection molding machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an online-blend type injection molding machine in which a reference position of thermal expansion in an injection direction is set near a connected part between an accumulator and an injection barrel of an injection device. <P>SOLUTION: A fixed frame F1A, which is attached and fixed to a base frame BF, surrounds a rear part of the injection barrel 14C of the injection device 14, and holds it in such a manner as to be slidable in a Z-direction. An annular arm 26 is elongated from a left end surface of the fixed frame; a left end surface of the arm abuts on a right end surface of a diameter-enlarged part 22 which is formed on the injection barrel; a fixing bracket 20 abuts on a left end surface of the diameter-enlarged part; and the left end surface of the arm and the fixing bracket are fastened together by means of a fastening bolt 24 in the state of sandwiching the diameter-enlarged part. Thus, the reference position of the thermal expansion in the injection direction can be set near the connected part between the accumulator and the injection barrel; a position of the accumulator is fixed; a machine can be assembled on the basis of the position of the accumulator; and maintenance work is facilitated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a continuous plasticizing type injection molding machine (hereinafter referred to as online) in which a continuous plasticizing device and an injection device are connected via an accumulator that temporarily stores a plasticized molten resin (hereinafter referred to as a plasticized resin). In particular, the present invention relates to an on-line blend type injection molding machine having a structure in consideration of thermal displacement in the injection axis direction of the injection device.

  Conventionally, in order to improve the efficiency of the injection molding machine, the plasticizing device and the injection device are separated, and an accumulator is provided between them. In particular, an apparatus has been proposed in which the operation rate of the plasticizing apparatus is increased by supplying plasticizing resin to the injection apparatus, and in particular, from the accumulator to the injection apparatus so that the plasticizing apparatus can be operated continuously. There has been proposed a continuous plasticizing type injection molding apparatus that can supply a plasticizing resin from a plasticizing apparatus to an injection apparatus even when a plasticizing resin is supplied, that is, an on-line blend type injection molding machine. (Patent Document 1)

  FIG. 2 shows a longitudinal section of the main components of a conventional general online blend type injection molding machine. In FIG. 2, reference numeral 10 denotes a twin-screw extruder constituting the above-described plasticizing apparatus, and a main synthetic resin material such as polypropylene (PP) is mainly used from a main feeder apparatus MF disposed above the twin-screw extruder. It is supplied to the hopper of the feeder device MF. A sub-feeder device SF is arranged on the left side, and an auxiliary molding material such as talc is similarly supplied to the hopper. The molding material supplied from each hopper into the heating cylinder 10A of the twin screw extruder 10 is melted, kneaded and plasticized by the two screw shafts 10B and 10C joined by the motor M via the gear box. VNT1 and VNT2 are a vacuum vent and an open vent, respectively.

An accumulator 12 formed integrally with the heating cylinder 10 </ b> A of the biaxial extruder 10 is disposed on the left end side of the biaxial extruder 10. The upper and lower cylinder chambers 12B and 12C of the accumulator 12 are provided with a plunger tip 12A provided at the lower end of the plunger 12D. The upper end of the plunger 12D is coupled to the piston PS1, and the piston PS1 is moved up and down by a hydraulic cylinder device 12E. Can be moved to.
As indicated by the arrows in the figure, the molten resin, that is, the plasticized resin, flows into the cylinder chamber 12C from the left end portion of the twin-screw extruder 10 through the outlet FG1. Since the discharge pressure of the twin-screw extruder 10 is relatively low, the piston PS1 is moved upward in order to keep the resin pressure when the plasticized resin flowing into the cylinder chamber 12C flows low. During this time, the valve VL1 provided at the lower part of the accumulator 12 is closed. Although not shown, a load cell is disposed in the middle of the plunger 12D, and the piston PS1 is hydraulically controlled by the load cell so that the resin pressure in the cylinder chamber 12C is within a predetermined range.

Reference numeral 14 denotes an injection device. When the valve VL1 is opened, an injection cylinder is formed on the injection side of the injection device 14 through the inflow port FG2 with the plasticized resin accumulated in the cylinder chamber 12C. It is received in the chamber 14A. That is, during the metering process, the plasticizing resin is supplied from the inlet FG2 into the injection cylinder chamber 14A formed by the injection barrel 14C, so that the cone-shaped plunger tip 14B provided at the left end of the plunger 14D moves to the right. Move backward to. In that case, the pressure oil to the injection cylinder device 18 is prevented so that the resin pressure in the cylinder chamber 12C of the accumulator 12 and the injection cylinder chamber 14A of the injection device 14, that is, the discharge pressure of the biaxial extruder 10 does not become higher than a predetermined value. The piston PS2 is moved backward by the supply / discharge of. During the metering operation, the valve VL2 is closed and opened after the metering is completed, and the molten resin in the injection cylinder chamber 14A moves the piston PS2 to the left to form the mold formed in the mold device 16 via the nozzle NZ. It is injected into the cavity. Reference numeral VL2 is a valve that shuts off the injection cylinder chamber 14A and the nozzle NZ side.
In the conventional on-line blend type injection molding machine shown in FIG. 2, the plasticizing resin supplied from the twin screw extruder 10 to the accumulator 12 is accumulated in order from the lower end in the cylinder chamber 12C in the accumulator 12. During the metering, it is supplied from its lower end to the injection cylinder chamber 14A via the inflow port FG2, and is ejected from the nozzle NZ after the metering is completed.
Further, in order to support the entire online blend type injection molding machine (hereinafter referred to as a main body) composed of the above-described twin-screw extruder 10, accumulator 12, and injection device 14, a fixed frame F1 is provided on a base frame BF provided on the ground G. And the injection device 14 is fixedly attached to the upper surface on the left end side. A fixed frame F3 that supports the heating cylinder 10A of the twin-screw extruder 10 on the rear side is fixed to the upper surface of the vertical frame F2 that is erected and fixed on the right end side of the fixed frame F1.
Reference sign FZ is a fixed zone and indicates that the mounting state of the injection device 14 with respect to the fixed frame F1 is fixed. On the other hand, reference symbol MZ is a slidable zone, and the biaxial extruder 10 (heating cylinder 10A, gear box, motor M) is attached to the fixed frame F3 so as to be slidable in the Z direction. The elongation due to thermal expansion of the screw extruder 10, that is, thermal deformation can be absorbed.
In order to appropriately set the contact state between the nozzle NZ and the fixed mold in the mold apparatus 16, the bolt BLT of the fixed frame F1 is loosened and the fixed frame F1 is moved left and right on the base frame BF during the initial setting operation. Can be moved and adjusted.

Patent No. 3303213 (FIGS. 1 to 3)

  By the way, in the structure that supports the main body of the conventional online blend type injection molding machine shown in FIG. 2, the mold apparatus 16 is normally fixed on the same base frame BF as the main body, and therefore, in the central portion of the fixing zone FZ. Since the distance from the reference position OG of thermal expansion in a certain Z direction to the tip position of the nozzle NZ is relatively large, the amount of thermal expansion also increases depending on the distance, and consequently the contact state between the nozzle NZ and the mold apparatus There is a problem that it becomes difficult to hold the nozzle well and normal injection operation cannot be performed. In particular, when the inlet FG2 is provided at the tip of the injection cylinder 14A as shown in FIG. 2, the center axis CL of the accumulator 12 is close to the mold device 16 side from the reference position OG, so that the amount of thermal expansion is also large. There is a problem that the main body becomes larger and heat deformation of the main body occurs.

Further, the lower space of the injection barrel 14C is necessary as an area where the operator approaches during maintenance work, assembly work, etc., and it is difficult to extend the fixed frame F1 below the accumulator 12. is there.
In the above-described example, the heating cylinder 10A of the twin screw extruder 10 is slidable in the Z direction on the fixed frame 3, but when the heating cylinder 10A is fixed on the fixed frame 3, For example, the thermal deformation of the main body cannot be absorbed at all, and for example, the central axis CL of the accumulator 12 may be inclined to the left and right.
Thus, since the injection device 14, the accumulator 12, and the twin screw extruder 10 are connected in a fixed form, thermal deformation of the injection barrel 14C of the injection device 14, deformation at the time of nozzle touch, etc., are at the position of the accumulator 12. It leads to a shift and appears as a shift of the connecting portion with the twin-screw extruder 10. As a result, a problem may occur in maintenance work or the like when the apparatus is assembled.

As a result of various studies and researches to solve the above-mentioned problems, the present inventor has determined the reference position of thermal expansion in the injection direction as the accumulator and the injection device in the structure supporting the main body of the online blend type injection molding machine. It has been found that the above-mentioned problem can be basically solved by using the vicinity of the joint with the injection barrel.
Accordingly, an object of the present invention is to provide an on-line blend type injection molding machine having a main body support structure in which a reference position for thermal expansion in the injection direction is provided in the vicinity of a joint portion between an accumulator and an injection barrel of an injection device.

In order to achieve the above object, an online blend type injection molding machine according to the present invention comprises:
A screw rotation motor that rotates a plasticizing plastic resin material that is melted, kneaded and plasticized in a heating cylinder at a predetermined speed, and continuously supplies and controls a required amount of the synthetic resin material into the heating cylinder. A continuous plasticizing device for the synthetic resin material comprising a feeder portion, a cylinder chamber connected to an outlet for guiding the plasticized resin extruded from the continuous plasticizing device, and a first chamber that is capable of moving forward and backward in the cylinder chamber An injection cylinder chamber having an accumulator having a plunger and a first drive means for driving the first plunger back and forth, and an inflow port for the plasticized resin connected to a flow path for guiding the plasticized resin extruded from the accumulator The formed injection barrel, the injection nozzle portion formed in communication with the injection direction of the injection cylinder chamber, and the second plan provided in the injection cylinder chamber so as to be able to advance and retract And a second drive means for driving the second plunger back and forth, and having an injection device for injecting plasticized resin from the injection nozzle into the mold cavity by driving the second plunger in the injection direction The blend type injection molding machine is characterized by comprising a fixing means for fixing the vicinity of the joint between the injection barrel and the accumulator to the fixing member side for the injection molding machine.

In that case, the fixed member is a fixed frame fixed on a base frame of the online blend type injection molding machine and slidably mounted on the upper surface of the injection barrel,
The fixing means can be composed of an arm having one end fixed to the fixing frame and the other end fastened in the vicinity of the coupling portion, and a fastening means for fastening the other end of the arm.

In this case, the fastening means includes a thick-diameter portion formed on the outer peripheral portion in the vicinity of the coupling portion of the injection barrel and a fixing metal fitting abutting on one end surface of the same-diameter thick portion, and the other end portion of the arm is It can contact | abut to the other end surface of the said large diameter part, and can be comprised so that the said large diameter part may be pinched | interposed and clamped by the other end part of the said fixing metal fitting and an arm.
Furthermore, it is preferable that a heater is attached to the other end of the fixing bracket and the arm. Further, the end portion on the anti-accumulator side of the continuous plasticizer can be slidably mounted on the fixed frame.

  According to the present invention, since the reference position for thermal expansion in the injection direction is provided in the vicinity of the coupling portion between the accumulator and the injection barrel of the injection device, the accumulator is not thermally deformed in the injection direction. The thermal displacement of the tip can be reduced as much as possible, and the maintenance work related to thermal deformation can be greatly reduced.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows an axial longitudinal section of a main part of an on-line blend type injection molding machine according to the present invention. In FIG. 1, the same reference numerals as those in FIG. 2 are the same as those in FIG. 2, and therefore, their descriptions are omitted because they are duplicated, and are mainly different from FIG. The components will be described.
Reference numeral F1A is a fixed frame attached and fixed to the base frame BF. The fixed frame F1A surrounds the rear portion of the injection barrel 14C of the injection device 14 (the right end side of the injection barrel 14C) and holds it slidable in the Z direction. An annular arm 26 extends from the left end surface of the fixed frame F1A. The left end surface of the arm 26 abuts on the right end surface of the thick portion 22 formed on the injection barrel 14C, and the left end of the thick portion 22 has the same diameter. The fixing metal 20 is brought into contact with the surface, and the left end surface of the arm 26 and the fixing metal 20 are fastened by fastening bolts 24 with the thick-diameter portion 22 interposed therebetween. Further, as shown in the drawing, the left end surface side of the fixture 20 is disposed adjacent to the joint between the bottom of the accumulator 12 and the injection barrel 14C.

Reference numerals HT1, HT2, HT3, and HT4 denote band heaters, and SHT is a bar heater. By disposing each heater as shown, when the molten resin is introduced into the injection barrel 14C, the molten state of the resin can be maintained.
Reference numeral MZ denotes a movement zone, which indicates that the injection barrel 14C is held slidable in the axial direction by thermal expansion with respect to the fixed frame F1A.

  In the present invention illustrated in FIG. 1, the left end portion of the arm 26 is fixedly coupled to the large diameter portion 22 of the injection barrel 14 </ b> C in the vicinity of the central axis CL of the accumulator 12, thereby coupling the accumulator 12 and the injection barrel 14 </ b> C. The vicinity of the part is fixedly supported by the fixed frame F1A. Thereby, even when the injection barrel 14C is thermally deformed, the movement of the connection position between the injection barrel 14C and the accumulator 12 is minimized. Therefore, it is easy to connect and attach the twin-screw extruder 10 connected to the accumulator 12, and the assemblability and maintenance are greatly improved.

  In short, in the present invention, the position of the connecting portion between the injection barrel and the accumulator is fixed, so that the position of the accumulator is fixed and the machine is assembled based on this, and this is done. This makes it possible to provide an on-line blend type injection molding machine that is not affected by thermal deformation of the injection barrel.

The preferred embodiments of the present invention have been described above. However, the present invention is not limited to those illustrated, and various modifications can be made by those skilled in the art. For example, the left end of the arm 26 and the large diameter portion 22 can be directly fastened with a bolt or the like without using the fixing bracket 20.
The same effect can be obtained by attaching the accumulator 12 itself to a fixed structure portion such as the fixed frame F1A and assembling the injection barrel 14C thereto.

1 is a longitudinal sectional view in the axial direction of a main part of an online blend type injection molding machine according to the present invention. It is a longitudinal cross-sectional view of the main part axial direction of the conventional online blend type injection molding machine.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Twin screw extruder 10A Heating cylinder 10B, 10C Screw shaft 12 Accumulator 12A Plunger tip 12B Upper cylinder chamber 12C Lower cylinder chamber 12D Plunger 12E Hydraulic cylinder device 14 Injection device 14A Injection cylinder chamber 14B Plunger tip 14C Injection barrel 14D Plunger 16 Mold Device 18 Injection cylinder device 18
20 fixing bracket 22 large diameter portion 24 fastening bolt 26 arm BF base frame BLT bolt CL accumulator central axis F1, F1A, F3 fixing frame FG1 inlet FG2 outlet FZ fixing zone G ground MZ moving zone MF main feeder NZ nozzle OG reference Position PS1, PS2 Piston SF Sub-feeder VL1, VL2 Valve

Claims (5)

A screw rotation motor that rotates a plasticizing plastic resin material that is melted, kneaded and plasticized in a heating cylinder at a predetermined speed, and continuously supplies and controls a required amount of the synthetic resin material into the heating cylinder. A continuous plasticizing device for the synthetic resin material comprising a feeder portion, a cylinder chamber connected to an outlet for guiding the plasticized resin extruded from the continuous plasticizing device, and a first chamber that is capable of moving forward and backward in the cylinder chamber An injection cylinder chamber having an accumulator having a plunger and a first drive means for driving the first plunger back and forth, and an inflow port of the plasticized resin connected to a flow path for guiding the plasticized resin extruded from the accumulator The formed injection barrel, the injection nozzle portion formed in communication with the injection direction of the injection cylinder chamber, and the second plan provided in the injection cylinder chamber so as to be able to advance and retract And a second drive means for driving the second plunger back and forth, and having an injection device for injecting the plasticized resin from the injection nozzle into the mold cavity by driving the second plunger in the injection direction. An on-line blend type injection molding machine comprising a blending type injection molding machine comprising fixing means for fixing the vicinity of a joint between the injection barrel and the accumulator to a fixing member side for the injection molding machine. The fixed member is a fixed frame fixed on a base frame of the online blend type injection molding machine and slidably mounted on the upper surface of the injection barrel.
The fixing means includes an arm having one end fixed to the fixing frame and the other end fastened in the vicinity of the coupling portion, and a fastening means for fastening the other end of the arm. The online blend type injection molding machine according to claim 1. The fastening means includes a thick-diameter portion formed on an outer peripheral portion in the vicinity of the coupling portion of the injection barrel, and a fixing fitting that contacts one end surface of the same-diameter thick portion, and the other end portion of the arm 3. The on-line blend type injection molding machine according to claim 2, wherein the on-line blend type injection molding machine is brought into contact with the other end surface, and is fastened by sandwiching the thick-diameter portion between the fixing bracket and the other end portion of the arm. The on-line blend type injection molding machine according to claim 3, wherein a heater is attached to the other end of the fixing bracket and the arm. The on-line blend type injection molding machine according to any one of claims 1 to 4, wherein an end portion of the continuous plasticizer on the side opposite to the accumulator is slidably mounted on the fixed frame.

Images