JPH0520501Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a thermocouple for a nozzle of an injection molding machine and an injection molding machine nozzle equipped with the thermocouple.

(Prior Art) A nozzle is attached to the tip of an injection cylinder of an injection molding machine, the tip of which comes into contact with a mold and injects molten resin.

This nozzle connects the mold and the injection cylinder and also determines the temperature of the molten resin injected into the mold, so a heating means such as a band heater is installed on the nozzle wall to prevent the molten resin inside the nozzle from being heated. Temperature may be controlled.

In such cases, it is necessary to measure the temperature of the molten resin inside the nozzle, but since it is not possible to directly measure the temperature of the molten resin by inserting the heat-sensitive part of a thermocouple into the molten resin, it is usually necessary to measure the temperature of the molten resin inside the nozzle wall. The internal temperature is measured and fed back to the control system as the molten resin temperature.

By the way, the temperature detection end shown in FIG. 4 is generally used to measure the temperature of molten resin in an injection cylinder or the like of an injection molding machine.

Such a temperature detection end is configured such that the heat sensitive part of the thermocouple 108 is enclosed in the tip of the protection tube 102 and
and a thermocouple 108 are integrated.

Furthermore, the threaded part 104 formed in the middle of the protective tube 102 is screwed into the threaded part of the hole drilled in the wall 100 of the injection cylinder or the like by rotating the nut 106 with a tool. the wall 10
It can be fixed to 0.

(Problems to be Solved by the Invention) The temperature detection end shown in FIG. 4 is attached to a thick-walled injection cylinder or the like because it is easy to handle.

However, since the temperature detection end shown in FIG. 4 is established by screwing the fixing screw part 104 of the protection tube 102, it is necessary to drill a relatively large diameter and deep hole in the wall 100. .

Furthermore, it is also necessary to provide a hole for mounting a temperature detection end in a heating means such as a band heater that heats the wall surface of the injection cylinder.

On the other hand, for thin and relatively small objects such as injection molding machine nozzles (hereinafter sometimes referred to as nozzles) that inject molten resin by contacting a mold, the conventional method shown in Fig. 4 is used. There are various problems with the temperature sensing end.

In other words, it is possible to make the protective tube that protects the thermocouple thinner, but the depth and diameter of the hole drilled in the nozzle wall are determined by the mechanical strength of the nozzle, the pressing force of the thermocouple against the bottom of the hole, and the screw strength. It is limited to a certain range from the viewpoint of processability and maintenance of the temperature detection end.

For this reason, it is often difficult to firmly fix a small-diameter protective tube directly to the nozzle wall by screwing.

Furthermore, providing a hole for attaching a temperature detection end to a heating means such as a band heater will also significantly reduce the heating efficiency of the nozzle wall surface.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a thermocouple for an injection molding machine nozzle that can be easily fixed to the nozzle without reducing the heating efficiency of the heating means, and an injection molding machine nozzle equipped with the thermocouple. It's about doing.

(Means for Solving the Problems) In order to achieve the above object, the present inventor proposes to support a thermocouple protective tube whose tip is inserted into a small hole in a nozzle wall from the top of a heating means such as a band heater. As a result of considering this idea and considering it to be effective, we arrived at this idea.

That is, the present invention provides a thermocouple for a nozzle of an injection molding machine, in which a protective tube whose tip is sealed with a heat-sensitive part for measuring the temperature of molten resin in the nozzle of an injection molding machine is attached to the nozzle using a fastener. The fastener includes a ring-shaped body to which the protective tube is fixed with its tip protruding inward and separated at least at one point, and a separated portion of the ring-shaped body. ,
A thermocouple for a nozzle of an injection molding machine, characterized by comprising a diameter reducing means for reducing the diameter of a ring-shaped body.

Further, the present invention provides an injection molding machine nozzle in which a heating means is attached to an outer wall surface, in which a tip of a protective tube constituting a thermocouple for the nozzle of the injection molding machine is inserted into a small hole drilled in the outer wall surface of the nozzle. , the thermocouple is inserted through the gap provided in the heating means so as to come into contact with the bottom of the small hole, and the diameter of the ring-shaped body is reduced by the diameter reduction means, so that the thermocouple is attached to the nozzle of the injection molding machine. An injection molding machine nozzle equipped with a thermocouple is characterized in that:

(Function) According to the present invention, the protection tube is fixed to the outer wall surface of the nozzle by reducing the diameter of the ring-shaped body constituting the fastener, and the tip of the protection tube in which the heat-sensitive part of the thermocouple is enclosed is fixed. It can be pressed against the bottom of the small hole in the nozzle wall.

In this way, the protection tube can be fixed while the tip of the protection tube is brought into contact with the bottom of the small hole in the nozzle wall without forming a threaded portion in the small hole in the protection tube and the nozzle wall.

In the present invention, it is not necessary to form threaded portions in the holes in the protection tube and nozzle wall, and the diameters of the holes in the protection tube and nozzle wall can be reduced.
It becomes possible to attach the temperature detection end to the nozzle using a small gap in the heating means, and the heating efficiency of the heating means is not reduced.

Furthermore, since the diameter of the hole drilled in the nozzle wall can be made smaller, the mechanical strength of the nozzle will not be reduced even if the hole is drilled deeper than before. Therefore, the tip of the protective tube to which the heat-sensitive part of the thermocouple body is attached can be brought as close as possible to the molten resin path in the nozzle, making it possible to measure the molten resin temperature in the nozzle more accurately. .

(Example) The present invention will be explained in more detail using the drawings.

FIG. 1 is a front view showing an embodiment of the present invention, in which a thermocouple A includes a protective tube 1 that protects the thermocouple body;
It is composed of a small piece 3, a tightening plate 4, and tightening screws 5, 5.

Among these components, a small piece 3 is welded near the tip of the protective tube 1, which includes the tip 2, in which the heat-sensitive part of the thermocouple body is enclosed, and as described later,
It is formed into a curved surface along the outer peripheral surface of the heating means attached to the outer wall surface of the nozzle.

Furthermore, tightening screws 5, 5 are provided at both ends of the small piece 3.
A hole (not shown) is formed into which the
A clamping plate 4 and a small piece 3 constituting the clamping tool are integrally connected by clamping screws 5, 5.

Such a small piece 3, a tightening plate 4, and tightening screws 5, 5
The fastener is constructed by:

That is, the small piece 3 and the clamping plate 4 form a ring-shaped body, and the diameter of this ring-shaped body is reduced by the clamping screws 5, 5.

Thermocouple A shown in FIG. 1 with such a fastener
A vertical cross-sectional view and a cross-sectional view of the nozzle equipped with the nozzle are shown in FIG. 2a and FIG. 2b, respectively.

In the nozzle of the injection molding machine used in this embodiment, a nozzle 10 having a molten resin passage 9 formed in the center thereof is attached to a cylinder head 11 of an injection cylinder.

A band heater 8 as a heating means is attached to the outer wall surface of the nozzle 10 with heater tightening screws 7, 7.

These heater tightening screws 7, 7 are provided at both ends of the band heater 8 where no heating element is present, and are attached to a mounting portion 6 consisting of vertical surfaces facing each other.
can be attached to.

In this embodiment, as shown in FIG. 2a, a notch 13 is formed in a part of the attachment part 6 of the band heater 8, and the thermocouple A is attached to the nozzle.

In addition, the protective tube 1 of the thermocouple A has a gap 1 formed at the seam of the band heater 8, as shown in FIG.
4 and attached to the nozzle, it is not necessary to provide a mounting hole for the thermocouple A in the band heater 8.

To attach the thermocouple A to the nozzle, first attach the band heater 8 to the nozzle 10 using the heater tightening screws 7, 7.
Attach to. At this time, the small hole drilled in the nozzle wall surface and the gap 14 formed at the seam of the band heater 8 are made to coincide with each other.

Next, the tip of the thermocouple A is inserted into the small hole so as to be in contact with the bottom of the small hole, and the small piece 3 attached to the protective tube 1 is inserted through the notch 13 of the attachment part 6 of the band heater 8 to the outer peripheral surface of the band heater 8. Attach it closely along the

After that, the tightening screws 5, 5 are inserted into the holes provided at both ends of the small piece 3 to connect and integrate the tightening plate 4 and the small piece 3.
The protective tube 1 is fixed to the nozzle 10 by tightening the small piece 3 and the small piece 3.

Due to the tightening force of the tightening screws 5, 5, the tip 2 of the protective tube 1 can be pressed and brought into contact with the bottom of the small hole in the nozzle wall.

As described above, according to this embodiment, the thermocouple A can be fixed to the small holes formed in the protective tube 1 and the nozzle body 10 without providing any threaded portions.

Furthermore, the thermocouple A can be attached using gaps such as joints of the band heater 5, and there is no need to make a special hole for attaching the thermocouple in the band heater 5.

Fig. 2 shows an example in which thermocouple A is attached to a nozzle using a band heater as a heating means. Thermocouple A is attached to the nozzle using a sheath type heater wrapped around the
An example of installing the

When such a sheath type heater is used, the conventional temperature detection end shown in FIG. 4 can be attached only to the portion not covered by the heater 12.

In this regard, according to the thermocouple A of this embodiment, since it is possible to arbitrarily provide a gap between the heaters 12 to the extent that the tip of the protective tube 1 can be inserted, a small hole can be made in the nozzle wall at an arbitrary location. The temperature of the molten resin in the molten resin channel 9 can be measured.

At this time, the outer peripheral surface of the sheath type heater is
By tightening the protective tube 1 with the clamping plate 4, the protective tube 1 is fixed while the tip 2 of the protective tube 1 is brought into contact with the bottom of the small hole.

In the embodiments described above, the protective tube is fixed by tightening the outer circumferential surface of the heating means with the fastener, but when the heating means is not used, the outer wall surface of the nozzle is tightened with the fastener. The protective tube may be fixed by tightening it.

Further, in the embodiment, the ring-shaped body is separated at two places, but it may be separated at one place.

It goes without saying that a plurality of thermocouples A in this embodiment may be installed in the longitudinal direction and/or circumferential direction of the nozzle body 10.

(Effects of the Invention) According to the present invention, the temperature of the molten resin passing through the nozzle can be measured at multiple locations on the nozzle, so the temperature of the molten resin in the nozzle can be controlled with high accuracy.

Furthermore, the holes bored in the protective tube that encloses the thermocouple body and the nozzle body are not provided with threaded portions, so that maintenance and the like can be easily performed.

[Brief explanation of the drawing]

Figure 1 is a front view showing one embodiment of the present invention;
The figures are a vertical cross-sectional view and a cross-sectional view of a nozzle with a band heater equipped with the thermocouple A shown in FIG. 1, and FIG. 3 is a vertical cross-sectional view of the nozzle with a sheath heater equipped with the thermocouple A shown in FIG. FIG. 4 shows cross-sectional views showing how the conventional temperature sensing end is mounted. In the figure, A...Thermocouple, 1...Protection tube, 2
... Tip of protection tube 1, 3 ... Small piece, 4 ... Tightening plate, 5 ... Tightening screw, 7 ... Heater tightening screw, 9
... Molten resin path, 10 ... Nozzle body.

Claims (1)

[Claims for Utility Model Registration] 1. A nozzle for an injection molding machine in which a protective tube, the tip of which is sealed with a heat-sensitive part for measuring the temperature of molten resin in the nozzle of the injection molding machine, is attached to the nozzle using a fastener. a ring-shaped body to which the protective tube is fixed with its tip protruding inward, and separated at least at one point; and a separating part of the ring-shaped body. 1. A thermocouple for a nozzle of an injection molding machine, comprising a diameter reducing means for reducing the diameter of a ring-shaped body. 2. In an injection molding machine nozzle in which a heating means is attached to the outer wall surface, the tip of the protective tube constituting the thermocouple according to claim 1 is in contact with the bottom of the small hole bored in the outer wall surface of the nozzle. The thermocouple is inserted through a gap provided in the heating means so that the thermocouple is in contact with the heating means, and the diameter of the ring-shaped body is reduced by the diameter reducing means, so that the thermocouple is attached to the nozzle of the injection molding machine. An injection molding machine nozzle equipped with a thermocouple.