JPH0524083A - Injection device of injection molding machine - Google Patents

Abstract

PURPOSE:To accurately detect injection forces by allowing loads to be applied equally on a whole load detector injection. CONSTITUTION:Between the forward support 11 and the rear infection support 17, two guide bars 21 are installed horizontally. Then, a pressure plate 30 is disposed movably along the guide bars 21 and, by the pressure plate 30, the rear end of a screw is supported. Screw advancing means is interposed between the pressure plate 30 and the rear injection support 17. A load detector 39 is provided for detecting injection forces being generated in accompany of the advance of the screw, and the forward injection support 11 and rear injection support 17 are supported on the frame 22 via a mutually separated forward slide base 45 and rear slide base 46. Since the forward slide base 45 and rear slide base 46 are separated each other, no restricting forces are applied on the guide bar 21 at the time of detecting Infection forces.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection device of an injection molding machine.

[0002]

2. Description of the Related Art Conventionally, a resin heated and fluidized in a heating cylinder is injected into a mold at high pressure and then cooled therein.
In an injection molding machine that solidifies or cures, and then opens the mold to take out the molded product, the screw is rotatably and retractably supported in the heating cylinder, and the screw must be advanced without rotating. It is possible to perform injection by using, and to measure by retreating while rotating the screw.

FIG. 2 is a sectional view of an injection device of a conventional injection molding machine, and FIG. 3 is a front view of the injection device of a conventional injection molding machine. In the figure, 11 is a front injection support, 12 is a heating cylinder attached to the front injection support 11, 1
Reference numeral 3 is an injection nozzle provided at the tip of the heating cylinder 12. Reference numeral 14 is a hopper for supplying resin into the heating cylinder 12, and 16 is a screw rotatably and advancingly supported in the heating cylinder 12.

Reference numeral 17 denotes a rear injection support which is arranged at a predetermined distance from the front injection support 11. The front injection support 11 and the rear injection support 1
7 is fixed to the slide base 20 via bolts 18 and 19, respectively, and two guide bars 21 are installed between the two in parallel to the horizontal direction. Reference numeral 22 denotes a frame, which slidably supports the slide base 20. Therefore, the injection device can be moved forward so that the nozzle touches the sprue bush of the fixed platen (not shown).

A pressure plate 30 is disposed between the front injection support 11 and the rear injection support 17 so as to be movable back and forth along the guide bar 21, and the rear end of the screw 16 is mounted on the pressure plate 30 by a bearing 31. It is rotatably supported via and is fixed in the axial direction by the regulating member 32. A screw rotation pulley 33 is connected to a drive source (not shown) via a belt and is driven at the time of measurement to rotate the screw 16
Retreat.

Reference numeral 34 is a feed screw rotatably supported by the rear injection support 17 via a bearing 35. The feed screw 34 is provided with a regulating member 36 at the rear end, and is regulated so as not to move in the axial direction with respect to the rear injection support 17. Reference numeral 37 is a nut screwed onto the feed screw 34. The nut 37 is fixed to the pressure plate 30, and the pressure plate 30 can be moved back and forth by rotating the feed screw 34. Therefore, an injection pulley 38 is attached to the rear end of the feed screw 34 and is connected to a drive source (not shown) via a belt.

By the way, in the injection device of the injection molding machine having the above-described structure, the screw 16 can be advanced through the pressure plate 30 by rotating the injection pulley 38 by a drive source (not shown) to perform injection. However, it is possible to realize a precise and reproducible injection process and pressure-holding process by detecting the emission output generated at this time.

Therefore, a load detector 39 composed of a strain gauge is provided between the pressure plate 30 and the nut 37. The load detector 39 moves the nut 37 by the rotation of the feed screw 34 to move the pressure plate 30 and the screw 16 forward, but at this time, a reaction force is generated by the resin in the heating cylinder 12, and the guide bar 21 Is stretched and the load detector 39 is
Is pressed.

[0009]

However, in the injection device of the conventional injection molding machine described above, the screw 16 is moved forward via the pressure plate 30 by rotating the injection pulley 38 by a drive source (not shown). When performing injection, the guide bar 21 is stretched, but since the front injection support 11 and the rear injection support 17 are fixed to the slide base 20 at the lower portion, the guide bar 21 is not attached to the slide base 2.
Receive binding force from 0.

Therefore, since a uniform stress is not applied to the entire load detector 39 due to bending stress applied to the guide bar 21, it becomes impossible to accurately detect the radiation output. The present invention solves the problems of the injection device of the conventional injection molding machine described above so that an even load is applied to the entire load detector and the injection output can be accurately detected. An object is to provide an injection device.

[0011]

Therefore, in the injection device of the injection molding machine of the present invention, a heating cylinder that rotatably and reciprocally supports the screw is fixed to the front injection support. A rear injection support is arranged so as to face the front injection support, and two guide bars are horizontally installed between the two.

A pressure plate is movably arranged along the guide bar between the front injection support and the rear injection support, and the rear end of the screw is supported by the pressure plate in a rotatable and axially restricted state. To be done. A screw advancing means for urging the pressure plate forward is disposed between the pressure plate and the rear injection support, and by advancing the pressure plate, the screw can be moved forward for injection.

A load detector is provided for detecting a radiation output generated as the screw advances, and the front injection support and the rear injection support are provided through a front slide base and a rear slide base which are separated from each other. Supported on the frame. The front slide base and the rear slide base can be connected by a connector having low rigidity.

[0014]

According to the present invention, the heating cylinder for rotatably and advancing and retracting the screw as described above is fixed to the front injection support. A rear injection support is arranged so as to face the front injection support, and two guide bars are horizontally installed between the two. A pressure plate is movably disposed along the guide bar between the front injection support and the rear injection support, and the rear end of the screw is supported by the pressure plate in a rotatable and axially restricted state. It

A screw advancing means for urging the pressure plate forward is disposed between the pressure plate and the rear injection support, and the screw is moved forward by advancing the pressure plate to perform injection. You can In addition, weighing can be performed by retracting the screw while rotating it. A load detector is provided for detecting the ejection output generated as the screw advances, and precise and highly reproducible injection and pressure holding can be performed corresponding to the ejection output.

The front injection support and the rear injection support are supported on the frame via a front slide base and a rear slide base which are separated from each other. When the screw advancing means is driven to advance the pressure plate, the screw moves forward, the resin in the heating cylinder is pushed out, and injection is performed. At this time, the guide bar tries to stretch due to the reaction force generated by the resin,
The load detector receives the reaction force and detects the radiation output.

Since the front slide base and the rear slide base are separated from each other, no restraining force is applied to the guide bar when the guide bar is about to extend. Therefore,
An even load is applied to the entire load detector. Further, when the front injection support is removed from the front slide base due to screw replacement or the like, the front slide base and the rear slide base may be connected by a connector having low rigidity in order to maintain the distance between them. In this case, if the rigidity of the connecting tool is low, the restraining force acting on the guide bar is also small, and there is no hindrance in detecting the ejection force.

[0018]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a front view of an injection device of an injection molding machine of the present invention. In the figure, 11 is a front injection support, 12 is a heating cylinder that is attached to the front injection support 11 and rotatably and reciprocally supports a screw inside, and 13 is an injection nozzle provided at the tip of the heating cylinder 12. is there. Reference numeral 14 is a hopper for supplying resin into the heating cylinder 12.

Reference numeral 17 is a rear injection support disposed at a predetermined distance from the front injection support 11. The front injection support 11 and the rear injection support 1
7 is fixed to a front slide base 45 and a rear slide base 46 via bolts 18 and 19, respectively, and two guide bars 2 are arranged in parallel with each other in the horizontal direction.
1 is erected. Reference numeral 22 denotes a frame, which slidably supports both the slide bases 45 and 46. Therefore, the injection device can be moved forward so that the nozzle touches the sprue bush of the fixed platen (not shown).

A pressure plate 30 is disposed between the front injection support 11 and the rear injection support 17 so as to be movable back and forth along the guide bar 21, and the rear end of the screw is mounted on the pressure plate 30 via a bearing. It is rotatably supported and fixed in the axial direction by a restriction member. 33 is a pulley for screw rotation,
It is connected to a drive source (not shown) via a belt, and is driven at the time of measurement to retract the screw.

A feed screw is rotatably supported by a bearing on the rear injection support 17 as in FIG. 2, and a nut 37 is screwed onto the feed screw. The nut 37 is fixed to the pressure plate 30, and the pressure plate 30 can be moved back and forth by rotating the feed screw. Therefore, an injection pulley 38 is attached to the rear end of the feed screw, and is connected to a drive source (not shown) via a belt.

By the way, in the injection device of the injection molding machine having the above structure, the screw can be advanced through the pressure plate 30 by rotating the injection pulley 38 by a drive source (not shown) to perform injection. The radiation output generated at this time can be detected. Therefore, a load detector 39 including a strain gauge is provided between the pressure plate 30 and the nut 37.
Is provided.

The guide bars 21 are horizontally arranged at the same height, the screw and the feed screw are arranged in the middle of the two guide bars 21, and they are placed on the same plane. The front injection support 11 and the rear injection support 17 are different slide bases 4 respectively.
It is supported by 5, 46 and can independently move forward and backward on a sliding rail such as a linear guide.

In this way, when the pressure plate 30 is advanced to perform injection, the ejection force is generated and the reaction force generated by the resin in the heating cylinder 12 tends to extend the guide bar 21. However, at this time, the front injection support 11 and the rear injection support 17 are
Since the slide bars 45 and 46 are independent of each other, the guide bar 21 does not receive a restraining force from the slide bases 45 and 46 when it is stretched.

Therefore, a uniform load can be applied to the entire load detector 39, and the load detector 39 can detect an accurate emission output. Further, since the injection output can be accurately monitored, it is possible to realize a precise and reproducible injection process and pressure holding process.
FIG. 4 is a view showing another embodiment of the injection device of the injection molding machine of the present invention.

In the figure, 45 is a front slide base,
Reference numeral 46 denotes a rear slide base, both of which have a small cross-sectional area and are connected by a connecting tool 47 having low rigidity against pulling. The guide bar 21 receives the stress when the ejection force is generated, and the connecting member 47 is provided only for connecting the front injection support 11 and the rear injection support 17 for relative positioning.

By doing so, when the guide bar 21 is stretched due to the ejection force generated by the injection, since the rigidity of the connecting member 47 is low, the restraining force does not occur and the load detector. With 39, an accurate emission output can be detected. Also, repair the screw of the injection device,
When exchanging, the bolts 18 and 19 are removed, the front injection support 11 is separated from the front slide base 45, the rear injection support 17 is separated from the rear slide base 46, and the rear injection support 17 and the rear slide base 46 are separated. The injection device is swiveled around the pin 48 arranged therebetween.

At this time, since the connecting member 47 connects the front slide base 45 and the rear slide base 46, the distance between the slide bases 45 and 46 is prevented from changing during turning and during screw repair and replacement. This can be prevented and the work for returning the injection device to the original position becomes easy.
The present invention is not limited to the above embodiment,
Various modifications can be made based on the spirit of the present invention, and they are not excluded from the scope of the present invention.

[0029]

As described in detail above, according to the present invention, the heating cylinder is fixed to the front injection support, and the rear injection support is disposed so as to face the front injection support, and two cylinders are provided between the two. The guide bar of is installed horizontally. Further, a pressure plate is movably arranged along the guide bar between the front injection support and the rear injection support, and a screw for urging the pressure plate forward is provided between the pressure plate and the rear injection support. Forwarding means is provided.

A load detector is provided for detecting the radiation output generated as the screw advances.
The front injection support and the rear injection support are supported on the frame via a front slide base and a rear slide base that are separated from each other. Therefore, when the load detector detects the radiation output generated with injection,
Since the front slide base and the rear slide base are separated from each other, the guide bar is not constrained. Therefore, an even load is applied to the entire load detector, and an accurate shot output can be detected.

Further, in consideration of maintainability, even when the front slide base and the rear slide base are maintained by a connecting member having a low rigidity in order to maintain the distance between the front slide base and the rear slide base, if the rigidity is sufficiently low, the restraining force acting on the guide bar is exerted. Becomes smaller, and the radiation output can be accurately detected.

[Brief description of drawings]

FIG. 1 is a front view of an injection device of an injection molding machine of the present invention.

FIG. 2 is a sectional view of an injection device of a conventional injection molding machine.

FIG. 3 is a front view of an injection device of a conventional injection molding machine.

FIG. 4 is a view showing another embodiment of the injection device of the injection molding machine of the present invention.

[Explanation of symbols]

11 Front injection support 12 heating cylinder 13 injection nozzle 17 Rear injection support 21 Guide bar 22 frames 30 pressure plate 39 load detector 45 front slide base 46 rear slide base

Claims (2)

[Claims] 1. A heating cylinder that rotatably and advancingly reciprocally supports a screw; (b) a front injection support that fixes the heating cylinder; and (c) is disposed facing the front injection support. And (d) two guide bars horizontally installed between the front injection support and the rear injection support, and (e) moving along the guide bar between the front injection support and the rear injection support. A pressure plate that is freely arranged and that supports the rear end of the screw so that it is rotatable and axially regulated; and (f) is arranged between the pressure plate and the rear injection support, and the pressure plate is attached to the front. A screw advancing means for urging; (g) a load detector for detecting a radiation output generated as the screw advances; (h) the front injection support; Isotropic injection support is,
An injection device of an injection molding machine, which is supported on a frame via a front slide base and a rear slide base that are separated from each other. 2. The injection device of the injection molding machine according to claim 1, wherein the front slide base and the rear slide base are connected by a connector having low rigidity.