JPH08281736A - Injection unit for injection molding machine - Google Patents

Abstract

PURPOSE: To facilitate material and color changes and to shorten the longitudinal size by providing a plunger for injecting and metering resin material in a barrel having one nozzle, and a unit for transmitting the rotatably drive force of a screw rotatably inserted into the barrel having a hopper to the screw. CONSTITUTION: When a predetermined amount of molten resin is metered to the front chamber 31 of an injection barrel 24, a plunger 27 is advanced by a hydraulic cylinder 26, and the metered resin is injected into a mold cavity via a nozzle 33. One common hopper 29 is mounted for all a plurality at the resin material supply port 37 of the barrel 25, the material supplied from the port 37 is molten by the shearing heat and the heater 30 provided on the outer periphery of the barrel 25 by the rotation of the screw 28, and fed to the chamber 31 of the barrel 24 in front of the plunger 27 via a passage 32. The rotary drive of the screw 28 is conducted by a power transmission unit 36.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection device and a vent type injection device of an injection molding machine, and more particularly to an injection device having a plurality of plasticizing devices for one injection nozzle.

[0002]

2. Description of the Related Art Conventionally, when a multi-color molding, a marble molding, or a molded product having the same shape and different materials or different colors are molded, an injection device having a plurality of plasticizing devices for one injection nozzle. Is well known. For example, as shown in FIG. 7, the injection cylinder 1 advances and retracts in the heating barrel 2 and two injection devices equipped with a screw 3 which is rotationally driven are provided, and one of the two injection devices is used for skin injection. 4, one is for core injection 5, and the skin material is first injected in a short shot state into the mold cavity (not shown) from the common nozzle 6 of both injection devices, and then the core material is the core of the skin material. There is known a device for performing so-called sandwich molding, in which a molded product in which the outer periphery of a core material is finally covered with a skin material is molded by injecting into a part.

[0003]

However, since a plurality of injection devices are arranged, it is difficult to form a device having a large longitudinal direction and to compact the whole device. There was a limit.

Further, since the screw performs both the plasticizing action and the filling action, it is possible to rotate and move in the axial direction. Therefore, not only the driving mechanism is complicated and the operation and maintenance thereof are difficult, but also In multi-color molding and the like, the molding operation was performed using all of a plurality of injection devices, so it was very troublesome and troublesome when changing materials and changing colors in preparation for the next lot.

It is an object of the present invention to provide an injection device having a plurality of plasticizing devices which are easy to change materials and colors and have a short longitudinal dimension, while eliminating the drawbacks found in the conventional devices. It is in.

[0006]

In order to achieve the above-mentioned object, the present invention advances and retracts in an injection barrel having a single molten resin injection nozzle, injects and measures a resin material, and advances and retracts the plunger. A driving device, a plurality of first heating barrels provided around the injection barrel, each having a hopper at the resin material supply port, a screw rotatably inserted in the heating barrel, and the screw. The injection device of the injection molding machine includes a rotary drive device for rotationally driving and a power transmission device for transmitting the power of the rotary drive device to each screw.

A block cylinder integrally provided with a plurality of first heating barrels each having the injection barrel and a hopper for supplying a resin material, and a plunger for advancing and retracting in the injection barrel to inject and measure a molten resin. A drive device for advancing and retracting the plunger, a screw rotatably inserted in the first heating barrel, a rotary drive device for rotationally driving the screw, and the power of the rotary drive device for each screw. An injection device of an injection molding machine having a power transmission device for transmitting to the injection molding machine.

Further, in place of the hoppers provided at the material supply ports of the plurality of first heating barrels, screws which are rotatably inserted in the same number of second heating barrels and second heating barrels as the first heating barrels. And a vent port provided between the plasticizer and the material supply port of the first heating barrel.

Further, the block cylinder is integrally provided with a second heating barrel, which is a vent type injection device of an injection molding machine.

Further, in place of the rotary drive device for rotationally driving the screw of the first heating barrel and the power transmission device for transmitting the power of the rotary drive device to each screw, each screw rotary drive device is provided with a plurality of screws. An injection device and a vent type injection device of an injection molding machine, which are characterized in that they are provided for each.

Further, an injection device for an injection molding machine is characterized in that an on-off valve is provided between an injection barrel front chamber in front of the plunger for measuring the molten resin and a front chamber in front of the screws of the plurality of heating barrels. And a vent type injection device.

Further, in place of the hoppers provided at the resin material supply ports of the plurality of first heating barrels, one hopper common to the plurality of first heating barrels is used, and an injection device of an injection molding machine. did.

Further, the screw inserted into the second heating barrel is rotationally driven by a plurality of common rotary driving devices, which is a vent type injection device of an injection molding machine.

Further, the screw inserted into the second heating barrel is rotationally driven by a plurality of common rotary driving devices, which is a vent type injection device of an injection molding machine.

Furthermore, the injection device and the vent type injection device of the injection molding machine are characterized in that the drive device for moving the plunger in the axial direction is a hydraulic cylinder.

Furthermore, the drive device for moving the plunger in the axial direction is an electric motor and a ball screw shaft for changing the rotation of the electric motor into a linear motion. The injection device of the injection molding machine and the vent type injection device. And

[0017]

According to the present invention, it is possible to obtain an injection device and a vent type injection device of an injection molding machine which are provided with a plurality of plasticizing devices which can be easily changed in materials and colors and whose longitudinal dimension is short.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, one embodiment of the present invention will be described with reference to FIGS. Reference numeral 20 denotes an injection device, which includes a bracket 23 movably attached to a guide rail 22 provided on a frame 21 and an injection barrel 24 and a plurality of pieces (six pieces in this embodiment).
No. 1 heating barrel 25 is assembled. A plunger 27 is inserted into the injection barrel 24 by a hydraulic cylinder 26 so as to be able to move forward and backward, and a screw 28 is rotatably attached inside the injection barrel 24 so as to be rotatable. A barrel 25 is attached.

Although the hydraulic cylinder 26 has been described as a drive device for the plunger 27, the drive device may be, for example, a servo motor and a ball screw shaft for converting the rotational motion of the motor into a linear motion.

A common hopper 29 is provided to the resin material supply port 37 of the first heating barrel 25 so that a plurality of common hoppers 29 are provided, and the resin material supplied from the resin material supply port 37 is supplied to the screw 28. It is adapted to be melted by a heater 30 provided on the outer peripheral surface of the shearing and heating barrel 25 by rotation and be fed into a front chamber 31 of the injection barrel 24 in front of the plunger 27 through a passage 32. The screw 28 is rotationally driven by a hydraulic motor 35 or a servomotor by a power transmission device 36 including a pulley, an idler and a belt.

When a predetermined amount of molten resin is measured in the front chamber 31 of the injection barrel 24, the plunger 27 moves forward (moves leftward in the drawing) by the hydraulic cylinder 26, and inside the mold cavity (not shown). The metered resin is injected through the nozzle 33. The passage 32
An opening / closing valve 34 is provided in the chamber, and the molten resin is selectively supplied from the passage 32 to the heating barrel front chamber 31 by opening and closing the valve.

As described above, the hopper for supplying the resin material is 1
Although an example of sharing one heating barrel with multiple heating barrels has been explained, of course, a hopper may be provided in each barrel, the former is convenient for plasticizing a large molded product, and the latter is a resin. You can easily change colors and colors. In addition, both of the plasticizers can be used to prepare and clean the next lot while the machine is not in use, so there is no machine downtime during the molding of the next lot, and productivity is improved. Is also good.

Further, although the injection barrel and the heating barrel are described as separate members in the above-mentioned embodiment, they may be integrated into a cylinder block 40 as shown in FIG. 3, whereby the structure is simple. Therefore, assembly and maintenance are also easy.

Further, regarding the vent type injection apparatus of this kind of apparatus, the case where there are three heating barrels is taken as an example, and FIGS.
In the material supply port 37 of the cylinder block 40 in which the first heating barrel 25 or the first heating barrel 25 and the injection barrel 24 are integrated, the second heating barrel 45 and the screw 42 are formed on the inner diameter surface of the barrel 45. Hydraulic motor 43
The three plasticizing devices rotatably fitted to the second heating barrel 45 are attached between the outlet of the second heating barrel 45 and the material supply port 37. A vent port 41 is provided for removing the volatile components and water that have been used.

As shown in FIG. 6, the hydraulic motor 43 is a power transmission device 4 having a pulley, an idler and a belt.
4 is attached, and a plurality of (3) second heating barrels 4
The five screws 42 are driven by one hydraulic motor 43. Here, the hydraulic motor 43 may be a single rotary drive source as described above, or of course, a rotary drive source may be provided for each second heating barrel 45. Further, the hydraulic motor is not limited to the hydraulic motor and may be a servo motor. May be

Although an example in which the second heating barrel 45 is attached to the cylinder block 40 has been shown as described above, this may be provided integrally with the cylinder block 40.

In the above-described three embodiments, the screw 28 may be rotationally driven by the hydraulic motor 35 or the servomotor, which is entirely driven by one drive motor and the power transmission device 36 as described above. Of course, a drive motor may be provided for each of the plurality of screws.

[0028]

Since the present invention is configured as described above, the length of the entire apparatus can be shortened and the material and the color can be easily changed, so that it is possible to easily cope with multicolor molding, marble molding and the like. Moreover, the plasticizing and measuring of the resin are done by the plasticizing screw and the plunger, respectively. The plasticizing and measuring are the same as the conventional screw.
It is not necessary to have a function that can perform the operation, and the drive mechanism has been simplified.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a Z arrow view of FIG.

FIG. 3 is a diagram showing an example in which a cylinder block in which an injection barrel and a heating barrel are integrated is used in another embodiment of the present invention.

FIG. 4 is a view showing a vent type injection device according to another embodiment of the present invention.

5 is a view on arrow Y of FIG.

FIG. 6 is a view on arrow X in FIG.

FIG. 7 is an explanatory view of a conventional sandwich molding apparatus.

[Explanation of symbols]

 21 frame 22 guide rail 23 bracket 24 injection barrel 25 first heating barrel 26 hydraulic cylinder 27 plunger 28 screw 29 hopper 30 heater 31 injection barrel front chamber 32 passage 33 nozzle 34 opening / closing valve 35 hydraulic motor 36 power transmission device 37 material supply port 40 Cylinder block 41 Vent port 42 Screw 43 Hydraulic motor 44 Power transmission device 45 Second heating barrel

Claims (11)

[Claims] 1. A plunger for advancing and retreating in an injection barrel having one nozzle for injecting molten resin, injecting and measuring a molten resin, a drive device for advancing and retracting the plunger, and a plurality of devices provided around the injection barrel. A first heating barrel each provided with a hopper at a resin material supply port; a screw rotatably inserted into the first heating barrel; a rotary drive device for rotationally driving the screw; An injection device of an injection molding machine, comprising: a power transmission device that transmits the power of a drive device to each screw. 2. A block cylinder integrally provided with a plurality of first heating barrels each having the injection barrel and a hopper; a plunger for advancing and retracting in the injection barrel to inject and measure a molten resin; and the plunger. A drive device for moving back and forth, a screw rotatably inserted in the first heating barrel, a rotary drive device for rotationally driving the screw, and the power of the rotary drive device is transmitted to each screw. An injection device of an injection molding machine having a power transmission device. 3. The hoppers provided at the material supply ports of the plurality of first heating barrels are rotatably mounted in the same number of second heating barrels and second barrels as the first heating barrels. The injection molding according to any one of claims 1 and 2, wherein a plasticizing device having a screw and a vent port provided between the plasticizing device and a material supply port of the first heating barrel. Machine injection equipment. 4. The injection device of an injection molding machine according to claim 2, wherein the block cylinder is integrally provided with a second heating barrel. 5. A plurality of screws each having a screw rotation drive device in place of a rotation drive device for rotationally driving the screw of the first heating barrel and a power transmission device for transmitting the power of the rotation drive device to each screw. The injection device of the injection molding machine according to any one of claims 1 to 4, wherein the injection device is provided for each. 6. An on-off valve is provided between the front chamber of the injection barrel in front of the plunger for measuring the molten resin and the front chamber of the plurality of heating barrels in front of the screws. An injection device of an injection molding machine according to any one of 1. 7. The one hopper common to the plurality of first heating barrels is used instead of the hoppers provided at the resin material supply ports of the plurality of first heating barrels, respectively. The injection device of the injection molding machine according to any one of 1. 8. The injection molding machine according to claim 2, wherein the screw inserted into the second heating barrel is rotationally driven by a common rotary driving device. Injection device. 9. The injection device for an injection molding machine according to claim 2, wherein the screw inserted into the second heating barrel is rotationally driven for each screw. . 10. The injection device of an injection molding machine according to claim 1, wherein the drive device for moving the plunger in the axial direction is a hydraulic cylinder. 11. The drive device for moving the plunger in the axial direction is an electric motor and a ball screw shaft for converting the rotation of the electric motor into a linear motion. Injection device of the described injection molding machine.