JPH10286849A - Preplasticization type injection unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To drive easily a cylinder for a mold clamping device in the direction of moving close to and away from, perform the delicate position adjustment with high accuracy at the time of nozzle touch or the like and improve workability at the time of maintenance, inspection, repair or the like of the cylinder in a preplasticization type injection unit provided with a plasticizing cylinder and an injection cylinder. SOLUTION: A screw device 14 with a first heating cylinder 10 as a plasticizing cylinder and a plunger device 20 with a second heating cylinder 16 as an injection cylinder are positioned properly by moving the plunger device in the direction of moving close to and away from a mold clamping device 22 independently each other, and a central shaft of the first heating cylinder 10 is set in parallel, and the central shaft of the second heating cylinder 16 is set orthogonally in the direction of moving close to and away from the mold clamping device 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pre-plasticization type injection device used for injection molding of a resin product in which a plasticizing process and an injection process of a resin material are separated, and in particular, a screw-type plasticizing cylinder and a plunger type. The present invention relates to a screw pre-plasticizing type injection device having an injection cylinder.

[0002]

2. Description of the Related Art Conventionally, as a kind of pre-plasticization type injection device, Japanese Patent Application Laid-Open No. 48-18351 and Japanese Utility Model Application Laid-Open No. 2-1
As disclosed in Japanese Patent No. 21913 and the like, a screw pre-plasticization type injection device including a screw-type plasticization cylinder and a plunger-type injection cylinder is known, and the uniformity and plasticity of plasticization of a resin material are known. It is widely used because of its excellent chemical ability.

However, in a conventional screw pre-plasticization type injection device, as described in the above-mentioned publication, a plasticization cylinder and an injection cylinder are formed in an integral structure, and nozzle touch adjustment and the like during molding are performed. At the time, both cylinders must be moved in the direction of approaching / separating from the mold clamping device as a whole, which makes it difficult to move quickly and difficult to finely adjust the nozzle touch. there were.

[0004] In addition, in the conventional pre-plasticizing type injection device, the plasticizing cylinder is generally disposed above the injection cylinder. There is a problem that it is difficult to secure a sufficient work space, and the work is troublesome. As described in Japanese Patent Application Laid-Open No. 48-18351, a plasticizing cylinder and an injection cylinder in which the central axes of both are substantially perpendicular to each other have been proposed. However, since the plasticizing cylinder and the injection cylinder are provided close to each other, it is difficult to secure a sufficient working space between the two cylinders. Is provided with a hydraulic cylinder mechanism for driving the plunger forward, so that the hydraulic cylinder mechanism hinders the mounting and dismounting of the plunger, and it is difficult to obtain good workability.

[0005] Further, in the conventional pre-plasticizing type injection apparatus, it is generally an important subject to suppress resin leakage to the rear of the plunger when the plunger inserted into the injection cylinder is driven forward. Then
For example, the outer diameter of the plunger is set as large as possible so that the gap between the sliding surface of the injection cylinder and the plunger is reduced. However, if the gap between the injection cylinder and the sliding surface of the plunger is made small, there is a problem that the sliding surface between the injection cylinder and the injection cylinder is liable to generate galling when the plunger slides, and it is difficult to obtain sufficient operation stability and durability because the slide surface is easily damaged. Was.

[0006]

Here, the present invention has been made in view of the above-mentioned circumstances, and claims 1 to 11 have been made.
The object of the invention described in (1) is that any of the plasticizing cylinder and the injection cylinder can be moved quickly and easily in the approaching / separating direction with respect to the mold clamping device, and the delicate position at the time of nozzle touch or the like can be achieved. An object of the present invention is to provide a pre-plasticizing injection device that can be easily adjusted.

The invention described in claim 4 also provides a pre-plasticized injection device which is excellent in the workability of attaching and detaching the plunger to and from the injection cylinder and which can easily perform maintenance and inspection and repair of the device. , Aim.

Further, the inventions according to claims 9 to 11 all provide a pre-plasticization type injection device in which the occurrence of galling of the plunger in the injection cylinder is prevented and the resin leakage in the injection cylinder is suppressed. It is also the purpose.

[0009]

In order to solve such a problem, the feature of the invention according to claim 1 is as follows.
(A) movable toward and away from the mold clamping device,
And a first heating cylinder having a central axis disposed in parallel with the moving direction, and inserting the resin material supplied into the first heating cylinder into the first heating cylinder. A screw device that heats and plasticizes while being fed forward by the rotating operation of the screw, and discharges it from a discharge nozzle at the tip of the first heating cylinder; and (b) between the mold clamping device and the screw device, It has a second heating cylinder which is movable independently of the screw device in the direction of approaching / separating from the mold clamping device and whose central axis is orthogonal to the moving direction. In addition, an injection nozzle is provided for allowing the mold clamping device to make a nozzle touch, and the discharge nozzle of the screw device is nozzle-touched to store the plasticized resin material supplied and stored in the second heating cylinder. A plunger device for causing the resin material stored in the second heating cylinder to be injected from the injection nozzle by a forward operation of a plunger inserted into the second heating cylinder, and (c) discharging the screw device. Of plasticized resin material discharged from the nozzle,
While allowing the inflow to the second heating cylinder in the plunger device, preventing the outflow of the resin material from the injection nozzle in the second heating cylinder, the resin material to the second heating cylinder While storing
During the movement of the plunger with respect to the second heating cylinder, the backflow of the resin material from the second heating cylinder to the first heating cylinder is prevented, and the resin material from the injection nozzle of the second heating cylinder is prevented. (D) a driving means for driving the screw device and the plunger device independently of each other in directions approaching and separating from the mold clamping device. In the device.

In the injection device having the structure according to the first aspect of the invention, the first heating cylinder constitutes a plasticizing cylinder, and the second heating cylinder constitutes an injection cylinder. That is, the screw device provided with the first heating cylinder is made to nozzle-touch the plunger device provided with the second heating cylinder, and the screw is provided under the condition that the plunger device is brought into nozzle contact with the mold clamping device. By rotating the screw in the device, the resin material is plasticized in the first heating cylinder, and the plasticized resin material is guided to the second heating cylinder of the plunger device and stored, and then the plunger is moved in the plunger device. By the forward operation, the resin material is injected into the mold clamping device, and the molding cavity is formed. And thus it is allowed to fill.

[0011] In such an injection device, the screw device having the first heating cylinder and the plunger device having the second heating cylinder are independently driven by the driving means with respect to the mold clamping device. The screw device and the plunger device can be moved quickly and easily with respect to the mold clamping device because they can be moved in the approaching / separating direction. The operability of position adjustment can also be improved.

The invention described in claim 2 is the first invention.
In the pre-plasticizing injection device having the structure according to the invention described in (1), the screw in the screw device is a reciprocating screw that is movable in the direction of the rotation center axis. In an injection device with such a structure, the screw can be continuously rotated and the molten resin can be accumulated in front of the screw even during injection, so that a large volume of molten resin can be plasticized uniformly and molded. The cycle can be improved.

[0013] The invention described in claim 3 is the first invention.
Or the pre-plasticizing injection device having a structure according to the invention described in 2 above, wherein the plunger device is detachable, and the first heating cylinder in the screw device under the condition that the plunger device is removed. The nozzle is capable of touching the mold clamping device, and the screw device constitutes an in-line screw type injection device. In the injection device having such a structure, plasticization and injection of the resin material can be performed only by the screw device, and therefore, according to the type of the resin material and the product, etc., the pre-plasticization type injection device is used. It is possible to select and adopt either molding or in-line screw injection molding.

The invention described in claim 4 is the first invention.
4. A pre-plasticizing injection device having a structure according to any one of claims 3 to 3, wherein in the plunger device, a hydraulic cylinder mechanism is provided forward of a movement direction of the plunger, and the hydraulic cylinder mechanism is provided. Is extended to the plunger side and connected to the base of the plunger, and the plunger is driven to be pulled forward by the hydraulic cylinder mechanism. In the injection device having such a structure, since the structure on the base side of the plunger is simplified, the workability of attaching and detaching the plunger can be improved, thereby making maintenance and inspection and repair of the device easy. It becomes. In addition, one or more hydraulic cylinder mechanisms are provided, and in particular, by providing a plurality of plungers at symmetrical positions sandwiching the plunger in a direction perpendicular to the axis, it becomes possible to advantageously exert an axial forward driving force on the plunger, Stabilization of the forward movement of the plunger can be advantageously achieved.

The invention described in claim 5 is the first invention.
A pre-plasticizing injection device having a structure according to any one of claims 1 to 4, wherein the plunger device is connected to the first heating cylinder by a nozzle touch of a discharge nozzle of the screw device. And the injection passage connected to the injection nozzle is formed at one point so as to be substantially orthogonal to the communication passage to the second heating cylinder. The valve means is provided by a rotary valve that is arranged to selectively connect a communication path to the second heating cylinder to the supply path and the injection path based on a rotation operation about one axis. It is characterized by being constituted. In the injection device having such a structure, the target valve means is constituted by a single rotary valve with a simple structure, and the switching operation thereof is simple and easy.

The invention described in claim 6 is the same as the invention in claim 5
In the pre-plasticizing injection device having a structure according to the invention described in the above, the groove extending in the circumferential direction provided on the outer peripheral surface of the rotary valve is covered with a valve housing, so that the communication passage of the heating cylinder is formed. A connection passage which is alternatively connected to the supply passage and the injection passage is formed, while the outer peripheral surface of the rotary valve is located on both sides in the axial direction of the concave groove and continuously extends in the circumferential direction. The formed circumferential groove is covered with a valve housing to form an annular resin reservoir for catching resin leaking from the connection passage, and is connected to the annular resin reservoir to pivot the inside of the rotary valve. A discharge passage extending in the direction and collecting the leaked resin trapped by the annular resin pool and discharging the collected resin to the outside is formed. In the injection device having such a structure, when a rotary valve having a simple structure according to the invention described in claim 5 is adopted, resin leaking from a sliding surface of the rotary valve is advantageously collected and discharged to the outside. Therefore, operation failure, contamination, and the like due to adhesion of the leaked resin can be advantageously prevented.

Further, the invention described in claim 7 is the same as claim 5
Or a pre-plasticizing injection device having a structure according to the invention described in 6 above, wherein the plunger device is supported so as to be movable in the approaching / separating direction with respect to the mold clamping device, and the rotary valve is rotated. The second heating cylinder is fixed to one side of the movably mounted housing with the rotary valve interposed therebetween, so that the plunger can be moved forward toward the rotary valve. On the other hand, a hydraulic cylinder mechanism for pulling the plunger in the forward direction is fixedly provided on the opposite side of the rotary valve from the second heating cylinder. In the injection device having such a structure, the second heating cylinder and the plunger and the hydraulic cylinder mechanism for driving the plunger are disposed extremely efficiently in space, and the plunger device is compact. It can be configured.

The invention described in claim 8 is the first invention.
8. A pre-plasticizing injection device having a structure according to any one of claims to 7, wherein in the mold clamping device, a plurality of tie rods for supporting a movable plate so as to be able to open and close a mold with respect to a fixed plate are provided. The tie rods are provided so as to protrude toward the plunger device, and the tie rods movably support the plunger device. In the injection device having such a structure, the guide mechanism for guiding the plunger device in the direction of approaching / separating from the mold clamping device using the tie rod of the mold clamping device is advantageously configured with a simple structure. You get.

The invention according to claim 9 is the first invention.
A pre-plasticizing injection device having a structure according to any one of claims 1 to 8, wherein in the plunger device, the plunger inserted into the second heating cylinder is larger than the plunger. It is characterized in that a piston ring having a diameter is extrapolated and assembled.
In the injection device having such a structure, the piston ring is slidably fitted to the inner peripheral surface of the second heating cylinder, so that resin leakage in the second heating cylinder is advantageously suppressed or prevented. In addition, since it is not necessary to increase the diameter of the plunger itself in order to prevent resin leakage, the occurrence of galling of the plunger in the second heating cylinder is also effectively prevented.

According to a tenth aspect of the present invention, there is provided a pre-plasticizing type injection apparatus having a structure according to any one of the first to ninth aspects. Guide means for guiding the plunger in the direction of movement is provided between a base for supporting the heating cylinder movably in the approaching / separating direction with respect to the mold clamping device and a base of the plunger. , Features. In the injection device having such a structure, the plunger, which can easily become a cantilevered support structure by the hydraulic cylinder mechanism for driving or the like, is guided in the moving direction by the guide means. The position is stable and the formation of galling on the second heating cylinder is advantageously prevented.

According to an eleventh aspect of the present invention, there is provided a pre-plasticizing type injection device having a structure according to any one of the first to tenth aspects, wherein the plunger is provided with the plunger. The plunger is supported so as to be displaceable in the direction perpendicular to the axis so that the center axis is aligned with the second heating cylinder.
In the injection device having such a structure, the plunger which tends to become a cantilever support structure by a hydraulic cylinder mechanism for driving or the like is automatically centered with respect to the second heating cylinder. The formation of galling on the second heating cylinder is advantageously prevented.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings.

First, FIGS. 1 and 2 show a main part of a pre-plasticization type injection apparatus as one embodiment of the present invention. The injection device includes a screw device 14 having a first heating cylinder 10 and a screw 12 as a screw-type plasticizing cylinder, and a second heating cylinder 16 and a plunger 18 as a plunger-type injection cylinder.
It is comprised including the plunger apparatus 20 provided with
The screw device 14 and the plunger device 20 are disposed so as to be independently movable toward and away from the fixed plate 24 of the mold clamping device 22. Then, after the resin material plasticized in the first heating cylinder 10 of the screw device 14 is guided and stored in the second heating cylinder 16 of the plunger device 20,
A molding cavity in a mold (not shown) mounted on the mold clamping device 22 is injection-filled.

More specifically, as the screw device 14, any of those conventionally used as in-line screw type injection devices can be used. Accordingly, although the structure of the screw device 14 is well-known, the screw device 14 will be briefly described as shown in FIG. A first heating cylinder 10 having a discharge nozzle 26 attached to a portion thereof is provided, and the screw 12 is inserted and arranged in the first heating cylinder 10. The band heater 28 is provided on the outer peripheral surface of the first heating cylinder 10.
Is mounted, and a nozzle tip 30 having a resin material discharge port 29 is attached to the tip of the discharge nozzle 26. The first heating cylinder 10 and the screw 12 are fixed and supported on a slide base that is reciprocally driven on the machine base 32 in the direction of approaching and separating from the mold clamping device 22. Also, screw 1
Numeral 2 is driven to rotate around a central axis by a hydraulic motor, and heats a resin material supplied from a rear side of the first heating cylinder 10 by a rotation operation in the first heating cylinder 10. While plasticizing, it is sent forward. Furthermore, the screw 12 is reciprocally driven in the direction of the central axis by a hydraulic cylinder mechanism, and the screw 12 is pushed back backward by the pressure of the resin material sent forward by the rotation of the screw 12. By the forward operation of 12, the plasticized resin material is discharged through the discharge nozzle 26. In addition, in order to prevent a backflow at the time of discharging the resin material, a backflow prevention valve 34 is attached to a tip portion of the screw 12.

The mold clamping device 22 in which such a screw device 14 is disposed so as to be able to approach / separate can be any of those conventionally used in injection molding of a resin product. The structure is well known. Briefly, as shown in FIG. 1, the mold clamping device 22 includes a fixed plate 24 and a movable plate which are arranged to face each other. The reciprocating drive in the approaching / separating direction is performed by the tightening cylinder. Then, by the reciprocating operation of the movable plate, the fixed die mounted on the fixed plate 24 and the movable die mounted on the movable plate are opened and closed. Further, the fixed platen 24 and the mold clamping cylinder for driving the movable plate are arranged to face each other, are fixedly supported by the machine base 32, respectively, and are provided between the opposed surfaces of the fixed platen 24 and the mold clamping cylinder. A movable plate is supported by these four tie rods 38, and the movable plate is guided in the approaching / separating direction with respect to the fixed plate 24. I have. In addition, fixed board 2
A nozzle insertion hole 40 into which a nozzle for injecting the resin material in the injection device is inserted into the center of the nozzle 4 so that the nozzle can be touched to a fixed mold mounted on the fixed board 24 is provided.

The screw device 14 is disposed so as to face the fixed plate 24 of the mold clamping device 22, and the center axis of the fixed plate 24 and the movable plate and the center of the first heating cylinder 10. The first heating cylinder 1 is disposed in parallel with each other so that the first heating cylinder 1 is positioned substantially on the same axis.
0 is displaced relative to the fixed platen 24 in the approaching / separating direction. In particular, in the present embodiment, the movement stroke of the first heating cylinder 10 with respect to the mold clamping device 22 is sufficiently set, and the first heating cylinder 1
0 is moved closer to the mold clamping device 22, so that the discharge nozzle 26 of the first heating cylinder 10 is directly nozzle-touched to the fixed mold through the nozzle insertion hole 40 of the fixed plate 24 of the mold clamping device 22. You can do it.

In short, in the injection device of the present embodiment, as the screw device 14 and the mold clamping device 22, both of the inline screw type injection molding machine generally used conventionally as an injection molding machine are used as they are. Therefore, the screw device 14 is operated and the screw 12 in the first heating cylinder 10 is operated.
The plasticization of the resin material and the injection into the molding cavity formed in the mold are performed by the rotation and reciprocating drive of, so that the desired resin molded product can be manufactured. Also from this, the specific structure of the screw device 14 and the mold clamping device 22 described above is as follows.
Either can be easily understood by those skilled in the art, and obviously does not require special explanation.

In other words, in the present embodiment, a major feature is that the plunger device 20 having a specific structure is provided between the opposing surfaces of the screw device 14 and the mold clamping device 22 constituting the inline screw type injection molding machine as described above. It has been arranged. As shown in FIGS. 1 and 2, the plunger device 20 has a rectangular flat base plate 42 as a base on which sliding bushes 44 are attached at four corners. At this time, the respective slide bushes 44 are externally inserted into the extension portions 46 of the tie rods 38 which are extended from the fixed plate 24 toward the screw device 14 and protruded, so that the base plate 42 is supported by the extension portions 46. While being guided, it is disposed between the opposing surfaces of the screw device 14 and the mold clamping device 22 so as to be movable toward and away from the fixed plate 24 of the mold clamping device 22. Then, the base plate 42 is reciprocated in the approach / separate direction with respect to the fixed plate 24 by the nozzle touch hydraulic cylinders 48, 48 mounted on both sides of the diagonal line of the base plate 42. I have.

A center block 50 is fixed to the center of the base plate 42 on the screw device 14 side. The center block 50 is located on a central axis connecting the first heating cylinder 10 of the screw device 14 and the mold clamping device 22, and the first heating cylinder 10 is located on the screw device 14 side of the center block 50. A nozzle touch portion 52 is provided for allowing the discharge nozzle 26 to make a nozzle touch. On the mold clamping device 22 side, the nozzle touch portion 52 projects toward the fixed platen 24 side, is inserted into the nozzle insertion hole 40, and is inserted into the fixed mold. Injection nozzle 5 to be touched
4 is fixed. A band heater is wound around the outer peripheral surface of the injection nozzle 54.

On one side (right side in the figure) of the center block 50 in the left-right direction (horizontal direction), a cylinder cylinder 58 having a thick cylindrical shape and having a band heater 56 mounted on the outer peripheral surface. Is fixed, whereby a second heating cylinder 16 is formed. The central axis of the second heating cylinder 16 is perpendicular to the approach / separation direction with respect to the mold clamping device, in other words, the screw device 14 It is configured to extend in a direction perpendicular to a central axis connecting the first heating cylinder 10 and the mold clamping device 22. Then, the plunger 1 is placed on the second heating cylinder 16 from outside.
8 has been inserted. Further, the plunger 18 is provided with a fitting groove extending in a circumferential direction at a tip portion inserted into the second heating cylinder 16, and the fitting groove is larger than the outer diameter of the plunger 18 body. Since the large-diameter piston ring 60 is inserted and mounted, the gap between the second heating cylinder 16 and the sliding surface of the plunger 18 is reduced without increasing the outer diameter of the plunger 18 body. .

On the other hand, the center block 50 is mounted on the other side (left side in the figure) in the left-right direction with a large-diameter circular block shape projecting on the same axis as the second heating cylinder 16 toward the opposite side. A portion 62 is integrally formed, and a cylinder block 64 is externally inserted into the mounting portion 62 and is fastened and fixed by a fixing nut 66 screwed to the mounting portion 62. The cylinder block 64 has a pair of hydraulic cylinders 68, 68 formed on both sides of the mounting portion 62 in the vertical direction (vertical direction).
Are protruded horizontally toward the second heating cylinder 16 side, and are arranged to extend parallel to the central axis of the second heating cylinder 16 on both sides vertically sandwiching the second heating cylinder 16. Has been established. The mounting portion 62 of the center block 50 is provided with a heat-dissipating hole 63 that extends on the central axis by a predetermined length and opens to the outer end surface.

The hydraulic syringes 68, 68
A bracket 74 having a central hole 72 having a diameter larger than that of the second heating cylinder 16 is attached to the distal end portions of the piston rods 70, 70, 70, 70
It is straddled and fixed. Also, this bracket 7
4, a disc-shaped blind flange 78 is detachably bolted to the outer opening of the central hole 72,
The second heating cylinder 16
The base end of the plunger 18 inserted into the plunger is attached. Thus, the plunger 18 is driven forward and backward in the second heating cylinder 16 by the pair of hydraulic cylinders 68, 68.

The plunger 18 has a two-part annular flange 82 which is detachably bolted to the inner surface of the blind flange 78 and is engaged with an annular fitting groove 80 formed on the base side. The blind flange 7
8 attached. In addition, a suspension bolt 84 is screwed to the annular flange 82, and when the blind flange 78 to which the plunger 18 is attached is removed for maintenance, inspection, repair, or the like, the suspension bolt 84 is used.
The plunger 18 and the blind flange 78 can be suspended and supported substantially horizontally.

Here, a clearance (rack) of a predetermined amount (for example, about 1 mm) is set in the radial direction between the annular flange 82 and the engaging portion of the plunger 18, and the diameter of the plunger 18 is set in the axial direction. A slight clearance (for example, about 0.1 mm) that allows directional displacement is set. Thereby, the hydraulic cylinder 6
When the piston rods 70, 70 are retracted at 8, 68 to pull the plunger 18 in the forward direction, the misalignment of the plunger 18 with respect to the second heating cylinder 16 and the displacement of the plunger 18 in the radial direction by the clearance amount. It is automatically canceled if allowed.

Further, guide rails 86, 86 extending in the longitudinal direction of the piston rods 70, 70 are fixedly provided on the base plate 42 at positions facing the piston rods 70, 70. A slider 88 that engages with these guide rails 86, 86 is attached. When the plunger 18 is driven by the hydraulic cylinders 68, 68, the sliders 88, 88 are guided by the guide rails 86, 86, and are supported by the piston rods 70, 70 of the hydraulic cylinders 68, 68 in a substantially cantilevered structure. The tilting of the plunger 18 is prevented, and the plunger 18 can be stably advanced in the direction of the central axis. As is apparent from this, in the present embodiment, the guide means is constituted by the guide rail 86 and the slider 88.

Further, the central axis of the second heating cylinder 16 is connected to the first heating cylinder 10 of the screw device 14.
A valve mounting hole 90 which is orthogonal to a central axis connecting the two central axes of the mold clamping device 22 inside the cylinder block 64 and penetrates vertically through the cylinder block 64 through this intersection. In contrast, a rotary valve 92 having a circular block shape is incorporated. In the cylinder block 64, a resin supply passage 94 extending from the valve mounting hole 90 toward the screw device 14 and opening to the nozzle touch portion 52, and extending from the valve mounting hole 90 toward the mold clamping device 22. A resin injection passage 98 connected to an injection hole 96 of the injection nozzle 54;
A communication passage 100 extending from the first heating cylinder 16 to the second heating cylinder 16 is formed. Each opening of the resin supply passage 94 and the resin injection passage 98 is connected to the opening of the communication passage 100. On the other hand, the valve mounting hole 90
Are located 90 degrees apart from each other on both sides in the circumferential direction on the inner peripheral surface.

On the other hand, as shown in FIG. 3, the rotary valve 92 is provided with a concave groove 102 extending in the circumferential direction with a length of about a quarter of the circumference of the axially intermediate portion. When the concave groove 102 is covered with the inner peripheral surface of the valve mounting hole 90, a connection passage 104 as a switching resin passage is formed. Also, the rotary valve 92
A drive arm 106 is fixed to the upper end of the rotary arm. The rotary valve 92 is connected to the drive arm 106 via the drive arm 106.
The valve switching hydraulic cylinder 108 supported by the cylinder block 64 is adapted to be turned around a central axis. And, the rotary valve 92
Is rotated back and forth by approximately 90 degrees, so that one of the resin supply passage 94 and the resin injection passage 98 is selectively switched and connected to the communication passage 100 by the connection passage 104. It has become. As is apparent from this, in the present embodiment, the valve housing is configured by the center block 50.

On the outer peripheral surface of the rotary valve 92,
A pair of circumferential grooves 110, 110 are provided on both sides in the axial direction of the concave groove 102 and extend continuously in the circumferential direction. These circumferential grooves 110, 110 are covered with the inner circumferential surface of the valve mounting hole 90. As a result, annular resin reservoirs 112 are formed on both sides of the connection passage 104. Further, a rotary valve 92 is provided at a portion where each circumferential groove 110 is formed.
And a through hole 114 extending radially through the inside of the groove and having both ends opened at the bottom of the circumferential groove 110, and connected to an intermediate portion of the through holes 114, 114, A discharge passage 116 is formed to extend downward on the central axis of the valve 92 and open at the lower end surface in the axial direction of the rotary valve 92. Thereby, when the resin material that is caused to flow through the connection passage 104 leaks between the sliding surfaces of the rotary valve 92 and the valve mounting hole 90, the leaked resin is captured by the annular resin reservoirs 112 and 112, and the through-hole is formed. From 114, it is collected and discharged through a discharge passage 116. In addition, below the discharge passage 116, resin receiving plates 120 and 122 as a tray for leaking resin are disposed between the cylinder block 64 and the bracket 74.

When manufacturing a target resin product by the injection molding machine having the above-described structure, first, the plunger device 20 is moved closer to the mold clamping device 22 to fix the mold clamped in the mold clamping device. The injection nozzle 54 is brought into nozzle touch with the mold, and the screw device 14
Is moved closer to the mold clamping device 22 so that the discharge nozzle 26 makes a nozzle touch with the nozzle touch portion 52 of the plunger device 20. In the connected state, the resin supply passage 94 is disconnected from the communication passage 100. Also, the plunger device 2
At 0, the plunger 18 is positioned at the forward end position, and the screw device 14 is positioned at the forward end position. The plunger device 20 is provided with a position sensor 126 for detecting the position of the plunger 18 at an arbitrary position between the forward position and the retreat position, so that the position of the plunger is controlled to be confirmed. .

In this state, the screw device 14 is operated, and the resin material is supplied to the first heating cylinder 10 while the screw 12 is driven to rotate. While being transferred forward by the rotation of the screw 12, it is heated and plasticized by heater heating and screw rotation heating, kneaded, and the resin material plasticized by the retreat of the screw 12 due to the resin pressure sent forward is screwed into the screw. Store in front of 12. Thereafter, the rotary valve 92 is switched, and the resin supply passage 94 is connected to the communication passage 100 by the connection passage 104.
And drive the screw 12 forward,
The resin material stored in front of the screw 12 is injected from the first heating cylinder 10, and is guided from the resin supply passage 94 to the second heating cylinder 16 in the plunger device 20 via the connection passage 104 and the communication passage 100. Then, in the second heating cylinder 16, it was confirmed by the position sensor 126 that the plunger 18 was retracted to a predetermined position by the resin pressure guided into the cylinder, and a predetermined amount of the plasticized resin material was stored. Thereafter, the rotary valve 92 is switched, and the communication passage 100 is
Is connected to the resin injection passage 98. In this state, by driving the plunger 18 forward, the resin material stored in the second heating cylinder 16 is molded by the mold clamping device 22 from the injection nozzle 54 through the communication passage 100 through the connection passage 104 and the injection hole 96. Inject and fill into the mold cavity in the clamped mold. Thereafter, similarly to general injection molding, after a lapse of a cooling time, the mold is opened in the mold clamping device 22 and a molded product is taken out to obtain a desired product.

Further, after the molded product was taken out by the mold clamping device, the mold was closed and clamped again, and the rotary valve 92 was switched in the plunger device 20 to plasticize the first heating cylinder 10 in the screw device 14. By guiding the resin material to the second heating cylinder 16 in the plunger device 20, the injection molding process as described above is repeated, and the target product can be continuously injection-molded.

In this embodiment, the screw 12 of the screw device 14 can be retracted by the pressure of the resin material sent forward. , The plasticized resin material is stored in front of the screw 12. Therefore, the rotary valve 92
, The communication between the first heating cylinder 10 and the second heating cylinder 16 is interrupted, and the plunger 18
During the process in which the stored resin material in the second heating cylinder 16 is injected into the molding cavity by the forward operation of the screw, the screw device 14 is operated to rotate the screw 12 to continuously plasticize the resin material. Can be done.

In the injection molding machine having the above structure, the screw device 14 and the plunger device 20 can move independently of each other in the direction of approaching / separating from the mold clamping device. , Those screw devices 1
4 and the plunger device 20 can be moved and positioned separately.
By separately moving 4,20, it is possible to easily and quickly move with a small driving force, and it is possible to easily and precisely perform fine position adjustment at the time of nozzle touch or the like. As a whole, workability can be dramatically improved.

Further, since the screw device 14 having the first heating cylinder 10 and the plunger device 20 having the second heating cylinder 16 have independent structures and can be separated from each other, For maintenance and repairs,
By locating the two devices 16 and 20 apart from each other, a working space can be advantageously secured, and workability is improved. Moreover, since the first heating cylinder 10 and the second heating syringe 16 are arranged so that their central axes are orthogonal to each other, a working space for maintenance and inspection and repair of the apparatus can be more advantageously secured. is there.

In addition, in the plunger device 20, the hydraulic cylinders 68, 68 for driving the plunger 18 are disposed in front of the plunger 18 to pull the plunger in the forward direction. The entire device can be made compact, and only the plunger 18 can be easily and quickly removed as compared with the case where a hydraulic cylinder mechanism is provided behind the plunger 18. Excellent workability during repair is ensured.

Further, in the plunger device 20,
The hydraulic cylinders 68 for driving the plunger 18 are
Brackets 74 which are disposed on both sides of the plunger 18 vertically and to which the plunger 18 is attached
Are also provided on both sides of the plunger 18 up and down, so that the inclination of the plunger 18 when the plunger 18 is pulled by the hydraulic cylinders 68 is effective. And the plunger 18 is driven stably in the axial direction, thereby advantageously preventing the plunger 18 from galling on the second heating cylinder 16 and the like. Resin leakage can also be effectively prevented.

Further, the plunger 18 is attached to the bracket 7
4 is mounted so that it can be displaced minutely in the radial direction with respect to the outer peripheral surface of the plunger 18 while automatically aligning the second heating cylinder 16 with the piston 4 and preventing resin leakage with the piston ring 60. Since the clearance between the inner peripheral surface of the second heating cylinder 16 and the inner peripheral surface of the second heating cylinder 16 is sufficiently set, the occurrence of galling or the like of the plunger 18 with respect to the second heating cylinder 16 is more advantageously prevented. Stable operation can be realized.

In the above-described injection apparatus, the respective central axes of the first heating cylinder 10 and the injection nozzle 54 are located on the same line, and are orthogonal to the central axis of the second heating cylinder 16. With this configuration, the passage length of the plasticized resin material can be set to be sufficiently short as a whole, and the passage of the resin material can be controlled by one rotary valve 92 disposed on the orthogonal point. Can be easily switched by the valve means having a simple structure.

Although the embodiment of the present invention has been described in detail above, this is a literal example, and the present invention is not construed as being limited to the embodiment.

For example, a step of guiding the plasticized resin material from the first heating cylinder to the second heating cylinder and storing it, and a step of injecting the stored resin material from the second heating cylinder into the molding cavity. In the above, the valve means for switching the flow path of the resin material is not limited to the rotary valve as illustrated, and may be constituted by a plurality of check valves, open / close valves, etc. disposed on the flow path of the resin material. .

A driving means for driving the screw device or the plunger device with respect to the mold clamping device, a driving means for driving the plunger forward / backward, or a rotary valve 92
For example, various drive means such as an electric motor and a hydraulic motor can be adopted as the switching drive means for the valves such as the hydraulic cylinder.

Further, the support structure of the plunger device 20 is not limited to the structure using the tie rods 38 of the mold clamping device 22 as shown in the embodiment. Alternatively, the plunger device 20 may be supported by a base movably installed on the machine base 32.

Further, the piston ring 60 mounted on the plunger 18 is provided in accordance with the clearance between the plunger 18 and the second heating cylinder 16 and the type of resin material.
A plurality may be provided.

In addition, although not enumerated one by one, the present invention
Based on the knowledge of those skilled in the art, various changes, modifications, improvements, and the like can be made, and unless such embodiments depart from the spirit of the present invention.
Both are included in the scope of the present invention,
Needless to say.

[0055]

As is apparent from the above description, in the pre-plasticizing injection device having the structure according to the first to eleventh aspects of the present invention, any one of the first heating cylinders as the plasticizing cylinder is used. And a plunger device having a second heating cylinder as an injection cylinder can be moved and positioned independently of each other with respect to the mold clamping device. The device and the plunger device can be easily and quickly moved with a small driving force, making it possible to easily and precisely adjust the fine position at the time of nozzle touch, etc., as well as to perform maintenance and inspection and repair of the device. At the time, the screw device and the plunger device are spaced apart from each other, so that a working space can be advantageously secured. The workability is being exhibited.

Further, in the pre-plasticizing injection apparatus having the structure according to the fourth aspect of the present invention, the plunger driving cylinder mechanism is disposed in front of the plunger, so that the structure on the base side of the plunger is provided. Is simplified, the attachment and detachment of the plunger becomes easy, and workability such as maintenance inspection and repair without the plunger can be remarkably improved.

Further, in the pre-plasticizing injection device having a structure according to the invention of claims 9 to 11,
In any case, prevention of the occurrence of galling of the plunger in the injection cylinder and suppression of resin leakage in the injection cylinder can be advantageously achieved in a compatible manner.

[Brief description of the drawings]

FIG. 1 is a horizontal sectional view showing a main part of a pre-plasticization type injection device as one embodiment of the present invention,
It is a figure corresponding to -I cross section.

FIG. 2 is a vertical sectional view showing a main part of the pre-plasticizing injection device shown in FIG. 1, and is a view corresponding to a II-II section in FIG.

FIG. 3 is an enlarged view of a main part for describing a rotary valve in the pre-plasticizing injection device shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 First heating cylinder 12 Screw 14 Screw device 16 Second heating cylinder 18 Plunger 20 Plunger device 22 Mold clamping device 26 Discharge nozzle 50 Center block 54 Injection nozzle 68 Hydraulic cylinder 70 Piston rod 74 Bracket 92 Rotary valve

Claims (11)

[Claims] A first heating cylinder which is movable in a direction approaching / separating from the mold clamping device and whose central axis is parallel to the moving direction; The resin material supplied into the heating cylinder is heated and plasticized while being fed forward by the rotation of the screw inserted into the first heating cylinder, and is discharged from the discharge nozzle at the tip of the first heating cylinder. A screw device, between the mold clamping device and the screw device, capable of moving in a direction approaching / separating from the mold clamping device independently of the screw device, and having a center axis with respect to the moving direction. Having a second heating cylinder arranged orthogonally,
The mold clamping device includes an injection nozzle that is caused to make a nozzle touch, and the discharge nozzle of the screw device stores the plasticized resin material supplied by being nozzle-touched in the second heating cylinder, A plunger device for injecting the resin material stored in the second heating cylinder from the injection nozzle by a forward operation of a plunger inserted in the second heating cylinder; and a plasticizing device discharged from a discharge nozzle of the screw device. While allowing the flow of the resin material into the second heating cylinder in the plunger device, and preventing the resin material from flowing out of the injection nozzle in the second heating cylinder, the second heating While storing the resin material in the cylinder, while moving the plunger with respect to the second heating cylinder, Valve means for preventing backflow of the resin material from the second heating cylinder to the first heating cylinder, and allowing injection of the resin material from an injection nozzle of the second heating cylinder; and A drive means for driving the plunger device independently of each other in a direction of approaching / separating from the mold clamping device, and a pre-plasticizing type injection device. 2. The pre-plasticizing injection device according to claim 1, wherein in the screw device, the screw is a reciprocating screw that is movable in a direction of a rotation center axis. 3. The apparatus according to claim 2, wherein said plunger device is detachable, and said plunger device is detached.
The first heating cylinder in the screw device is capable of nozzle-touching the mold clamping device, and the screw device constitutes an in-line screw type injection device. A pre-plasticizing injection device as described. 4. The plunger device, wherein a hydraulic cylinder mechanism is provided forward of the plunger in the moving direction, and a piston rod of the hydraulic cylinder mechanism extends toward the plunger and is connected to a base of the plunger. The pre-plasticizing injection device according to any one of claims 1 to 3, wherein the plunger is driven to be pulled in the forward direction by the hydraulic cylinder mechanism. 5. In the plunger device, a supply passage connected to the first heating cylinder by a nozzle touch of a discharge nozzle of the screw device, and an injection passage connected to the injection nozzle, Each of the second heating cylinders is formed so as to intersect at one point so as to be substantially orthogonal to the communication passage to the second heating cylinder, and is disposed at the intersection, and the second operation cylinder is rotated based on one axis. The pre-plasticizing type according to any one of claims 1 to 4, wherein the valve means is constituted by a rotary valve which selectively connects a communication passage to the heating cylinder to the supply passage and the injection passage. Injection device. 6. A communication passage of the heating cylinder is selected from the supply passage and the injection passage by covering a circumferentially extending groove provided on an outer peripheral surface of the rotary valve with a valve housing. While the connecting passages are formed on the axially opposite sides of the concave groove, circumferential grooves formed on the outer peripheral surface of the rotary valve and formed continuously in the circumferential direction are covered with the valve housing. Thereby, an annular resin reservoir for trapping the resin leaking from the connection passage is formed, and connected to the annular resin reservoir, extends inside the rotary valve in the axial direction, and is captured by the annular resin reservoir. 6. The pre-plasticizing injection device according to claim 5, wherein a discharge passage for collecting the leaked resin and discharging the resin to the outside is formed. 7. In the plunger device, the plunger device is supported so as to be movable toward and away from the mold clamping device,
For a housing on which the rotary valve is rotatably mounted, on one side of the rotary valve,
The second heating cylinder is fixedly provided so that the plunger can be moved forward toward the rotary valve, while the plunger is located on the opposite side of the rotary valve from the second heating cylinder. 7. The pre-plasticizing injection device according to claim 5, wherein a hydraulic cylinder mechanism for pulling the plunger in the forward direction is fixed. 8. The mold clamping device, wherein a plurality of tie rods for supporting the movable plate with respect to the fixed plate so as to open and close the mold are provided, and the tie rods are protruded toward the plunger device, The pre-plasticizing injection device according to any one of claims 1 to 7, wherein the plunger device is movably supported by the tie rods. 9. In the plunger device, with respect to the plunger inserted into the second heating cylinder,
9. The pre-plasticizing injection device according to claim 1, wherein a piston ring having a diameter larger than that of the plunger is extrapolated and assembled. 10. The plunger device, wherein the plunger is provided between a base for supporting the second heating cylinder so as to be movable toward and away from the mold clamping device and a base of the plunger. The pre-plasticizing injection device according to any one of claims 1 to 9, further comprising guide means for guiding in a moving direction. 11. The plunger device according to claim 1, wherein the plunger is supported so as to be smallly displaceable in a direction perpendicular to the axis so that the plunger is centered on the second heating cylinder. The pre-plasticizing injection device according to any one of the above.