JP3350783B2 - Compressed core position detection device in injection compression device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection compression molding machine, and more particularly to a compression core position detecting device in an injection compression device.

[0002]

2. Description of the Related Art An injection compression molding machine is used for molding lenses and various precision molded products, and has an injection compression device. In the injection compression apparatus, a compression core is driven by a core compression piston incorporated on a movable platen side to compress a molding material, for example, a resin, in a cavity. In injection compression molding, it becomes possible by controlling the resin volume and resin pressure in the cavity with high precision. For this purpose, it is necessary to precisely control the position of the compression core, and it is necessary to detect the position of the compression core with high accuracy.

With reference to FIGS. 3 and 4, a description will be given of an injection compression device provided with a conventional compression core position detecting device. 4
A fixed platen 2 is attached to two tie bars 21 (only two are shown).
2 and a movable platen 23 are attached. A fixed mold 24 and a movable mold 25 are respectively attached to surfaces of the fixed platen 22 and the movable platen 23 facing each other. The movable platen 23 incorporates a core compression piston 26 on the movable mold 25 side, and the movable mold 25 incorporates a compression core 27 driven by the core compression piston 26. The core compression piston 26 is driven by a drive source different from the drive source of the movable platen 23. In other words, the core compression piston 26 and the compression core 27 can be displaced independently of the movable platen 23. The movable platen 23 and the movable mold 2 are moved by a mold clamping mechanism (not shown).
This is because when the mold 5 is moved to perform mold clamping, the core compression piston 26 is further driven to perform compression molding.
A cavity 28 is formed between the stationary mold 24 and the compression core 27. In the figure, the two-dot chain line indicates the displacement position of the joint surface between the core compression piston 26 and the compression core 27 during the injection compression operation.

[0004] The compressed core position detecting device is constructed as follows. The movable platen 23 has a detection bar 30
A space for accommodating the same is formed. Utilizing this space, one end of the detection bar 30 is connected to the core compression piston 26, and the other end of the detection bar 30 is led out of the movable platen 23 and connected to the position sensor 31. The detection bar 30 is supported by a guide 32 such that the detection bar 30 can be displaced in a space as the core compression piston 26 moves. The guide 32 also has a function of preventing the rotation of the core compression piston 26 via the detection bar 30.

In this compression core position detecting device, when the core compression piston 26 moves, the compression core 2
7. The detection bar 30 also moves horizontally, and the bar 31-1 connected to the other end of the detection bar 30 is displaced. The position sensor 31 detects the position of the compression core 27 by detecting the amount of displacement of the bar 31-1.

[0006]

In the above-described compression core position detecting device, since the position sensor 31 is disposed outside the movable platen 23, the length of the detection bar 30 increases as the size of the injection compression device increases. When the length of the detection bar 30 is increased, bending is likely to occur, and a detection error increases. Further, since the detection bar 30 is sandwiched by the guides 32 at a plurality of places in the space of the movable platen 23, chattering occurs due to sliding resistance, which also causes a detection error.

It is an object of the present invention to provide a compressed core position detecting device in which a detection error hardly occurs.

[0008]

Compressed core position detecting device according to the present invention SUMMARY OF THE INVENTION the compressed core incorporated in the movable die, the molding of the driven by the core compression piston incorporated in the movable platen side cavity In the injection compression apparatus for compressing a material, a through hole is provided in the core compression piston along a moving direction of the compression core, and a movement amount of the compression core can be detected through the through hole. A detector is provided.

Specifically, the detector is provided with a sensor holder inserted into the through hole and on the compression core side of the sensor holder.

[0010] A through hole may be provided in the movable platen at a position corresponding to the through hole along the moving direction of the compression core, and a movement amount of the compression core may be detected through the two through holes. A detector may be provided so as to perform the detection.

Then, a sensor holder for signal line derivation is inserted into the two through holes, and the detector is provided on the compression core side of the sensor holder.

[0012] The detector may be provided at the exit of the through hole of the movable platen opposite to the compression core.

[0013] A detection bar may be inserted into the two through holes so as to contact the compression core, and the detector may detect a displacement of the detection bar.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIG. 1, the same parts as those in FIG. 3 are denoted by the same reference numerals. In this embodiment, a through hole 26-1 is provided in the core compression piston 26 along the moving direction of the compression core 27, and the compression core 27 is also provided at a position of the movable platen 23 corresponding to the through hole 26-1. Are provided along the moving direction of the through hole 23-1. As a result, the through holes 23-1 and 26-1
Are connected in a straight line. And the through holes 23-1, 26
-1, the sensor holder 12 is inserted, and the detector 10 is provided on the compression core 27 side of the sensor holder 12 so that the amount of movement of the compression core 27 can be directly detected. The signal line 11 of the detector 10 has two through holes 26-
1, 27-1 through the sensor holder 12 inserted into the through hole 23 of the movable platen 23 on the opposite side to the compression core 27.
-1 exit. The sensor holder 12 is attached to the movable platen 23 by a nut 13.

As the detector 10, a non-contact type sensor for detecting the distance to the end face of the compression core 27 is used. Such a sensor is a known sensor such as a laser sensor or an ultrasonic sensor. Can be used. Further, a known contact-type sensor may be used.

In any case, when the mold clamping process starts, the injection compression device moves together with the movable platen 23. Then, when the compression molding starts during the mold clamping process, the compression core position detecting device detects the compression core 2 from the detector 10 at that time.
The position of the compression core 27 is detected by detecting the amount of displacement of the compression core 27 using the distance to the end face of the reference numeral 7 as a reference position.

Although the detector 10 is provided in the sensor holder 12 in FIG. 1, if a space can be secured between the rear end side of the core compression piston 26 and the movable platen 23, this space is used. Alternatively, the movable platen 23 may be provided with a contact type detector such as a laser sensor. In this case, no sensor holder is required. Further, a detector can be provided at the exit of the through hole 23-1 of the movable platen 23 on the opposite side of the compression core 27 to perform position detection. Also in the case of this modified example, the detector is a contact type such as a laser sensor, and detects the displacement of the end face of the compression core 27 through the through holes 23-1 and 26-1 having no sensor holder.

FIG. 2 shows a second modified example of the above modification.
Is shown. In FIG. 2, the detection bar 14 is inserted into the two through holes 23-1 and 26-1 so as to contact the end face of the compression core 27, and the detector 15 is inserted into the movable platen 23 on the outlet side of the through hole 23-1. Is provided. Detector 1
Numeral 5 is for detecting the amount of displacement of the detection bar 14. The detection bar 14 may be fixed to the end face of the compression core 27 by welding or the like, but is preferably simply placed in a contact state in consideration of maintainability. In this case, the detector 15
, The detection bar 14 is always compressed by the compression core 2 by a spring or the like.
Means for pressing against the end face of the device 7 is required.

[0019]

According to the compressed core position detecting apparatus of the present invention described above, the position of the compressed core is directly detected, so that highly accurate detection on the order of microns is possible.
As a result, the position of the compression core can be precisely controlled. As a result, the resin volume and resin pressure in the cavity can be controlled with high accuracy,
A molded article having good molding quality can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an injection compression device including a compression core position detection device according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing an injection compression device including a compression core position detection device according to a second embodiment of the present invention.

FIG. 3 is a cross-sectional view illustrating an injection compression device including a conventional compression core position detection device.

FIG. 4 is a sectional view taken along line A in FIG. 3;

[Explanation of symbols]

 10, 15 Detector 11 Signal line 12 Sensor holder 13 Nut 14, 30 Detection bar 21 Tie bar 22 Fixed platen 23 Movable platen 24 Fixed mold 25 Movable mold 26 Core compression piston 27 Compression core 28 Cavity 31 Position sensor 32 Guide

Claims (8)

(57) [Claims] The method according to claim 1 compressed cores incorporated in the movable mold, in driven by the core compression piston incorporated in the movable platen side injection compression device for compressing the molding material in the cavity, the core compression piston Wherein a through-hole is provided along the moving direction of the compression core, and a detector is provided so as to be able to detect the amount of movement of the compression core through the through-hole. Compressed core position detection device. 2. An injection compression apparatus according to claim 1, wherein a sensor holder is inserted into said through hole, and said detector is provided on said compression core side of said sensor holder. Compressed core position detecting device. 3. The compressed core position detecting device according to claim 2, wherein said detector is one of a contact type detector and a non-contact type detector. . 4. The compression core position detecting device according to claim 1, wherein a through-hole is provided along a moving direction of the compression core at a position corresponding to the through-hole on the movable platen, and the two through-holes are provided. A detector for detecting the position of the compressed core in the injection compression apparatus, wherein a detector is provided so as to be able to detect the amount of movement of the compressed core through the compressor. 5. The compressed core position detecting device according to claim 4, wherein a sensor holder for signal line derivation is inserted into the two through holes, and the detector is provided on the compressed core side of the sensor holder. A compression core position detecting device in an injection compression device characterized by the above-mentioned. 6. The compressed core position detecting device according to claim 5, wherein said detector is one of a contact type detector and a non-contact type detector. . 7. The compression apparatus according to claim 4, wherein said detector is provided at an exit of a through hole of said movable platen opposite to said compression core. Core position detection device. 8. The compression core position detecting device according to claim 7, wherein a detection bar is inserted into the two through holes so as to contact the compression core, and the detector detects a displacement amount of the detection bar. A compression core position detection device in an injection compression device, characterized in that: