JPS6245679B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in plasma torches.

Conventional plasma torches, particularly small plasma torches, employ a water-cooling method that uses water to cool their nozzles. The first example is
To explain the figure, reference numeral 1 denotes an electrode 1 which is suspended in a torch body 3 and a nozzle 2 attached to the end of the torch body 3, and is attached to the torch body 3 via an insulator 7. Electrical cords 11a and 11b are connected to the torch body 3, respectively. Reference numeral 4 denotes a cooling water passage provided in the torch body 3 and connected to a cooling water inlet pipe 5 and an outlet pipe 6. 8 is a pipe that supplies plasma gas to the space formed between the electrode 1, the torch body 3, and the nozzle 2; 9 is a shield cap attached to the torch body 3 so as to surround the nozzle 2; 10 is a shield cap This is a pipe that supplies shielding gas into the interior of the shielding gas.

As mentioned above, in the conventional plasma torch, since the cooling water passage 4 is provided in the torch body 3, the torch not only has a large diameter, but also has a cooling water inflow pipe 5, an outflow pipe 6, and a shield cap 9. The disadvantage is that the structure of the torch becomes very complicated due to the attachment of the torch, and the torch becomes large. Also,
There is also a method disclosed in Japanese Patent Application Laid-Open No. 139645/1983, but similar points are not taken into consideration.

The present invention aims to eliminate the above-mentioned drawbacks and to reduce the size and weight of a torch. a supply system that supplies plasma gas to the outer peripheral space of the electrode, and a supply system that supplies nozzle nozzle shield gas through the porous metal layer of the nozzle, and the plasma gas supply system and the electrode Connect the side energizing cord coaxially,
The present invention is characterized in that the shield gas supply system and the nozzle side energizing cord are provided coaxially.

An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 2, 12 is an electrode attached to a cap 14 attached to an electrode holder 13 via a collet 15, 16 is a nozzle holder attached to the electrode holder 13 via an insulator 17, and 18 is a core member 18a. A nozzle is provided with a porous metal layer 18 on the outer peripheral surface of the nozzle, and the porous metal layer 18 is formed by sintering small metal balls. The electrode 12 is suspended in such a nozzle 18.

19a and 19b are torch joints attached to the electrode holder 13 and nozzle holder 16, respectively; 20a and 20b are torch joints 20
a, 20b and hose joints 21a, 21b, respectively, and 22a, 22b are hoses attached to the hose joints 21a, 21b, respectively, and the plasma gas flowing through the hose 22a is connected to the outer space 26 of the electrode 12. The shielding gas 25 flowing through the hose 22b is also supplied to the outer space 27 of the nozzle 18.

23a is an energizing cord; one energizing cord 23
A is housed in the hose 22a and has one end connected to the hose joint 21a, and the other energizing cord 23b is housed in the hose 22b and has one end connected to the hose joint 21b.

The present embodiment has the above-described configuration, and the plasma gas 24 introduced into the outer space 27 of the electrode 12 via the hose 22a, the hose joint 21a, and the torch joint 19a is ejected from the tip of the nozzle 18 and becomes a working gas. . On the other hand, hose 2
2b, the shielding gas 25 introduced into the outer space 27 of the nozzle 18 via the hose joint 21b and the torch joint 19b flows through the porous metal layer 18b of the nozzle 18 to cool the core material 18a, and the opening of the nozzle 18 Shields the surrounding area and protects the workpiece from the atmosphere. Since the shield gas 25 is used to cool the nozzle 18 in this way, compared to the conventional example in which the nozzle is cooled with water, the cooling passage and piping can be omitted and the direct diameter of the torch can be significantly reduced.

As explained above, according to the present invention, the torch is made smaller by using shielding gas to cool the nozzle, and the structure is simplified and lighter by forming the energizing cord and the gas supply system coaxially. It is possible to make changes.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a conventional plasma torch, Figure 2 is a cross-sectional view of a conventional plasma torch.
The figure is a sectional view showing an embodiment of the plasma torch of the present invention. 12... Electrode, 18... Nozzle, 18a... Core material, 18b... Porous metal layer, 22a, 22b...
...Hose, 23a, 23b...Electrification cord, 24
...Plasma gas, 25...Shield gas, 26
……space.

Claims (1)

[Claims] 1. A nozzle having a porous metal layer provided on the outer peripheral surface of a core material, an electrode suspended in this nozzle, a supply system that supplies plasma gas to a space outside this electrode, and a porous metal layer of the nozzle. The plasma gas supply system and the electrode side energizing cord are coaxially provided, and the shielding gas supply system and the nozzle side energizing cord are coaxially provided, respectively. A distinctive plasma torch.