JPH028736Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Technical Field] This invention relates to a sharp heating element used in synthetic resin injection molding machines and the like.

[Prior Art] Conventionally, a hot runner hot chip shown in FIGS. 6a and 6b is known as a basic structure of a sharp heating element in which a heat generating part is provided at a sharp tip part.

To explain each figure, 1 is a conical tip end portion, 2 is a cylindrical body portion following the tip tip portion 1, and the whole body forms a shell-shaped cylindrical body a. 3
indicates a body heater located and fixed within the cylindrical body 2, and has the function of heating and keeping the molten resin in the spray facing the outer periphery of the cylindrical body 2 warm to prevent the inconvenience of cooling and solidifying it.

By the way, if we explain the structure and function of the chip heater, that is, the heat generating part b provided in the sharp tip part 1, respectively, a and b will be explained first. The tip is formed so that it passes through the axial center of the sharp tip portion 1 and slightly protrudes from the tip thereof, and the protruding portion is formed as the heat generating portion b.

In addition, b is the same as that shown in Utility Model Application No. 57-11017, and in particular, the heating part b consists of a sharp tip part 1 and a nichrome wire, that is, a heater wire 4, inserted into the sharp tip part 1 from the inside. are integrally welded by arc discharge or the like in an inert space of an inert gas such as argon to form the alloy metal part There are advantages that can be enhanced.

However, in the above-mentioned conventional example, since the exothermic part b is formed in the protruding state of the heater wire 4, it wears out due to the continuous sliding action of the resin during injection and distribution of the molten resin. It is easily susceptible to the effects of the metal alloy and has problems in long-term use.Although b is formed of the alloy metal part X and has excellent wear resistance, it requires welding in an inert gas environment, resulting in high processing costs.
There is a problem that it is not suitable for mass production.

[Summary of the invention] This invention was made by paying attention to the points mentioned above, and was developed as a sharp heating element that is extremely simple to process and has excellent wear resistance. The tip of the heater wire that has passed through the heating wire is exposed to the sharp tip portion, and both are mechanically fixed by caulking to form a heat generating portion.

[Example] Below, an example of this invention is shown in Figures 1 and 2.
This will be explained with figures.

Note that parts that are the same as or correspond to those in the conventional example are denoted by the same reference numerals, and detailed description thereof will be omitted.

In each figure, c indicates a heat generating portion, which is formed by securely fixing the sharp tip portion 1 and the heater wire 4 inserted through the cylindrical body a using a desired caulking device. In this case, the tip of the heater wire 4 is
As shown in the figure, it may or may not penetrate through the sharp end portion 1, as long as the caulked portion has a heater function. Further, the heat generating portion c naturally also forms one electrode portion of the heater wire 4.

Note that the illustrated body heater 3 may or may not be provided, and the cylindrical main body a has a sharp tip portion 1.
and the cylindrical body portion 2 may be separate or integral.

Next, three examples of caulking means will be explained with reference to FIGS. 3 to 5.

First, FIG. 3 shows a case where a rotary punch 5 is used, and a sharp tip portion 1 formed separately from the cylindrical body portion 2 of the main body a is inserted into the desired chuck mechanism together with the heater wire 4 inserted therein. 6, and is lowered while rotating the rotary punch 5 to form a conical concave drawing part 7 to form a sharp tip part 1.
It is used for caulking.

Next, in FIGS. 4a and 4b, three crimping rollers 8 are used to crimp the tip sharp portion 1 of the above structure, and the tip is crimped in the space 9 formed by the three crimping rollers 8 in contact with each other. The caulking process can be performed by exposing the sharp portion 1 and rotating and advancing the caulking roller 8 in the same manner as described above to squeeze the outer surface of the sharp tip portion 1. Note that, since the roller 8 is cylindrical, the sharp tip portion 1 is processed into a cylindrical shape, and therefore can be sharpened by cutting or the like if necessary.

Further, if the crimping roller 8 itself is used as a truncated conical conical roll in advance, it is possible to sharpen the conical shape at one time.

Finally, as shown in FIG. 5, the sharp end portion 1 can be caulked by simply clamping the recesses 10 of the two upper and lower caulking plates 9. By tapering the shape of the recess 10, the necessary conical sharpening can be achieved.

Although three examples of crimping means have been described above, the crimping means itself may have any configuration.

[Effects of the invention] According to this invention, the sharp tip part can be formed by mechanical processing using a caulking step, and furthermore, this part becomes one electrode of the heater wire and is obtained as a heat-generating part, so that processing and forming is easy. It can be provided efficiently and inexpensively, and by using a material with high mechanical strength on the outer periphery of the heater wire with a sharp tip, the fragility of the heater wire itself can be compensated for and it can be used as a highly durable local heater. It can be used not only as a hot runner chip for synthetic resin injection molding materials, but also for various other purposes.

[Brief explanation of drawings]

1 and 2 are explanatory cross-sectional views showing two embodiments of the sharp heating element according to this invention, and FIGS. 3, 4 a, b, and 5 show three examples of caulking means,
Fig. 3 is a side explanatory view, Fig. 4 a is a side explanatory view, b
5 is an explanatory front view of the same as above, FIG. 5 is an explanatory view of a slope, and FIGS. 6A and 6B are explanatory cross-sectional views of two conventional examples. 1... Sharp tip, 2... Cylindrical body, 4... Heater wire, 5... Rotating punch, 8... Crimping roller,
9... Caulking plate, a, b, c... Heat generating part, X...
Alloy metal part.

Claims (1)

[Claims for Utility Model Registration] (1) The tip of the heater wire is inserted into a cylindrical body whose entire shape is a cannonball, and the tip of the heater wire is exposed to a sharp tip, and the sharp tip is caulked to connect the heater wire to the heater wire. A sharp heating element that is mechanically fixed to the tip of a wire to form a heat generating part. (2) The sharp heating device according to claim 1 of the utility model registration, wherein the tip of the heater wire is passed through the shell-shaped cylindrical body at a position facing from the tip and caulked to form a heat generating portion. body. (3) The tip of the heater wire is located inside the tip of a bullet-shaped cylindrical body and is caulked to form a heat generating part.
Sharp heating element as described in section.