JPS5921257B2 - nozzle device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hot chamber die casting machine (hereinafter referred to as HDM).
The present invention relates to an improvement of the nozzle device (abbreviated as ), which facilitates heating of the nozzle device that is maintained at a high temperature, reduces power consumption and fuel consumption, and provides a highly efficient nozzle device.

Figure 1 shows a schematic diagram of the HDM. In the figure, a pot 2 attached to an electric furnace 1 has a molten metal 3 (
A pump body 5 having a cylinder 4 is suspended in the molten metal 3 from a frame (not shown).

When the plunger 6 fitted into the cylinder 4 is moved downward by the piston rod 9 of the hydraulic cylinder 8 connected via the coupling 7, the molten metal 3A in the pump body 5 passes through the passage 10 to the nozzle body. 11, the mold 1 through a nozzle device 13 consisting of a nose tip 12, etc.
4 and cooled to become a product.

Here, the nozzle device 13 located between the injection pump 15 consisting of the pump body 5, the cylinder 4, the plunger 6, etc. and the mold 140 has an inner hole 16 serving as a passage for the molten metal 3A, so it is always kept at a high temperature and the inside is kept at a high temperature. The temperature of the molten metal 3A passing through the hole 16 is prevented from decreasing, so that the molten metal 3A can pass through the inner hole 16 without solidifying.

Therefore, the conventional nozzle device 13 is heated by a heating device (not shown) such as a gas combustion flame or an electric heater.

In particular, the mold 14, which is fixed to the main body 18 of the die-casting machine via a locate ring 19, has a water hole 20 through which cooling water passes, and the mold 14 is maintained at a low temperature.
Since the tip portion 21 of the connected nozzle body 11 tends to have a low temperature, a highly insulating packing 22 is installed between the tip portion 21 and the mold 14 to prevent heat dissipation.

Furthermore, as mentioned above, a heating device using a gas combustion flame, an electric heater, etc. is used to heat the nozzle device of a conventional HDM. HDMs for alloys are small in size, but HDMs for alloys with high melting points, such as magnesium alloys or aluminum alloys, have a melting point of 570 to 670°C.
In the case of M, it is large and consumes a large amount of gas and electricity, and the mold of the die-casting machine main body requires a large amount of space to accommodate this heating device, resulting in a decrease in strength and an increase in size due to the structure. ing.

In addition, with HDM, the temperature of the mold that engages with the nozzle is low, and the thermal energy dissipated toward the mold is large than the nozzle tip. The amount of dispersion is quite large.

Therefore, it is necessary to apply thermal energy to the nozzle tip commensurate with the amount of dissipation.

The present invention has been developed in view of this point, in which the outer periphery of the tip of the nozzle body is surrounded by an electrode layer made of a heat-resistant metal made of a good electric conductor, and the electric power supplied from the electrode connected to this electrode layer is applied between the electrode layers. The present invention provides a nozzle device characterized by heating a heating element and maintaining a nozzle body at a predetermined temperature via an electrode layer.

The details of the present invention will be explained below with reference to the drawings.

FIG. 2 is a detailed view of the main parts of a nozzle body showing an embodiment of the present invention, and parts in the figure that have the same functions as those in FIG. 1 are designated by the same reference numerals.

Reference numerals 23 and 24 are electrode layers made of a heat-resistant metal and made of a good electric current and communicated with the electrodes 25 and 26. A heating element 27 is provided between these electrode layers 23 and 240, and the tip portion 21 of the nozzle body 11
It is closely attached to the outer periphery of.

When the heating element 27 is heated by the electrode layers 23 and 24, the heat generated in the heating element 27 easily flows into the nozzle body 11, increasing the efficiency.
3.24 can be made thin, so the nozzle device 13 including the heating device can be small and efficient.

Generally, the nozzle body 11 is made of cast iron, but if it is made of heat-resistant steel such as stainless steel (SUS304), the heating element 27 is fixed directly to the outer surface of the nozzle body 11, and the nozzle body 11 and the electrode are The heating element 27 may be heated by supplying power between the layers 240.

The temperature of the tip 21 of the nozzle body 11 is the same as that of HD for lead-based alloys.
The heating element 2
In No. 7, since a temperature of about 600 to 800° C. is sufficient, a metal, ceramic, or cermet heating element can be used.

Furthermore, the connection between the electrode layers 23 and 24 made of heat-resistant metal and the nozzle body 11 can be made very strong.

Furthermore, if a heat insulating material reflector is placed around the electrode layer 24 to prevent heat dissipation from the outer surface thereof, the efficiency can be further improved.

In the present invention, since a heating element that generates a large amount of heat is provided at the tip of the nozzle that dissipates a large amount of thermal energy, it is possible to maintain the tip of the nozzle at a predetermined temperature.

Further, unlike thin wires, the heating element is resistant to mechanical vibration and has a long life, so the nozzle device according to the present invention is easy to handle.

Further, since the tip of the nozzle device is to be inserted into a narrow space of the mold, it is preferable that the tip of the nozzle device has a simple shape, and the present invention is suitable in this respect.

Furthermore, the thickness including the heating element and electrodes is several mm or less, and the appearance of the nozzle device of the present application is much simpler than when a conventional general-purpose heater is used.

Furthermore, since the electrode layers 23, 24 and the heating element 27 are formed using completely conventional techniques using widely used thermal spraying technology and powder metallurgy technology, they can be provided at low cost and with stable performance.

[Brief explanation of the drawing]

FIG. 1 is a main sectional view of the HDM, and FIG. 2 is a detailed sectional view illustrating the structure at the end of the nozzle body of the present invention. 23.24... Electrode layer, 25, 26...
- Electrode, 27...Heating element.

Claims (1)

[Scope of Claims] 1. A nozzle body located between an injection pump and a mold and connected to the mold and having an inner hole that serves as a passage for molten metal injected from the injection pump. The heating element is sandwiched between the heating elements on the outer circumferential surface near the tip, and the electrode layers are connected to the electrodes and brought into close contact with the entire outer circumferential surface near the tip of the nozzle body. A nozzle device, characterized in that the nozzle body is maintained at a predetermined temperature by heating a heating element. 2. Claim 1, characterized in that a heating element is brought into close contact with the entire outer circumferential surface near the tip of a nozzle body made of a heat-resistant metal, and the heating element is covered with an electrode layer having an electrode. nozzle device.