JPH04108976U - Tapered nozzle of plasma torch - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a plasma torch having a tapered shape so that the lower end of the torch does not come into contact with the material to be cut when cutting a material having irregularities with a plasma cutting machine. [Structure] The lower surface of the flange 1a provided on the upper outer periphery of the nozzle 1 and the seat surface 2a provided on the inner periphery of the cap 2 are brought into close contact to ensure electrical continuity between the nozzle 1 and the cap 2,
The nozzle 1 and the electrode 5 inserted into the nozzle 1 are fixed to the torch body. An O-ring 6 inserted into a groove provided at the lower end of the cap 2 comes into close contact with the outer periphery of the nozzle 1 below the flange 1a, and seals the cooling water flowing through the nozzle cooling water passage 7. By exposing the lower end of the nozzle 1 from the lower end of the cap 2 and by making the apex angle θ of the cone at the lower end of the nozzle smaller than the apex angle of the cone formed by the cap of a conventional plasma torch, the diameter of the lower end of the torch can be reduced from the conventional plasma torch. It is thinner and has a sharper shape.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to a tapered nozzle for a plasma torch.

0002

[Conventional technology]

The nozzle attached to the lower end of the plasma torch is attached to the lower end of the cylinder as shown in Figure 2. A protrusion is provided, and a plasma jet and plasma arc are generated at the center of the lower end of this protrusion. It is equipped with a small hole that restrains the working gas in the upper cylinder as a swirling flow or an axial flow. A swirler 4 is fitted between the pole 5 and the nozzle 1, and the swirler 4 and the insulating cylinder 3 are connected to each other. The electrode 5 is gripped via the . In addition, the hole provided at the lower end of the cap 2 is close to the conical surface formed at the lower end of the protrusion of the nozzle 1, excluding the lower surface of the nozzle 1 Covers other parts. Formed between the lower outer periphery of nozzle 1 and the inner periphery of cap 2 The space formed therein serves as a nozzle cooling water passage 7 that cools the lower part of the nozzle 1.

0003 In the plasma torch shown in Fig. 2, which directly cools the nozzle 1 with water, the nozzle 1 is The function of the overturning cap 2 is as follows. (1) Fix the nozzle and the parts inserted into the nozzle to the torch body. (2) Ensure electrical continuity with the nozzle. (3) Seal the cooling water flowing around the nozzle to prevent it from leaking to the outside. In order to realize these functions, cap 2 is attached to the nozzle near the tip of the plasma torch. It has a structure that makes metal contact with the tip of 1. Also, near the tip of the plasma torch The insulating cylinder 3 is fitted around the outer periphery of the electrode 5, and the swirler is attached to the lower end of the insulating cylinder 3. 4. Since multiple parts are included, such as the nozzle 1 into which these parts are inserted, the Both the diameter of the torch and the apex angle θ of the conical portion at the tip of the torch must become large.

0004

[Problem that the idea aims to solve]

Plasma cutting machines can not only be used for two-dimensional cutting of flat plates, but can also be mounted on robots and used outside of automobiles. It is also used for three-dimensional cutting work such as component parts. However, the thick tip of the conventional There are problems with the ugly torch, as shown below. (1) When teaching the robot to memorize the cutting trajectory, apply it to the material to be cut. The work is difficult because the bamboo line is hidden by the torch. (2) When the torch height, that is, the distance between the bottom surface of the nozzle and the material to be cut, is set to a specified dimension, During cutting, the lower end of the torch may come into contact with the material being cut in the valley-shaped concave area. Ru. For this reason, move the torch close to the material to be cut until the torch height reaches the specified dimension. I can't do that (I'm not approachable). Therefore, it was unavoidable that the size was larger than the specified size. Since cutting is performed at a certain torch height, the quality of the cut in that area is extremely poor, and in some cases, It becomes impossible to cut. (3) Because the nozzle fixing part of the cap is close to the lower end of the nozzle, it It is easy for molten metal to adhere to the surface and cause abnormal discharge, i.e., double arc points. This damage causes water to leak from the metal contact between the nozzle and the cap. Problems such as this may occur.

[0005] This invention enables the above-mentioned conventional plasma torch to be used without changing the basic structure of the conventional plasma torch. Providing a tapered nozzle for plasma torch that can solve the problem The purpose is to

[0006]

[Means to solve the problem]

In order to achieve the above object, the tapered nozzle of the plasma torch according to the present invention has an electrode The upper cylindrical part of the nozzle has a small hole at the lower end that encloses the plasma arc and ejects the plasma arc. A flange is provided on the outer periphery, and a seating surface is provided on the lower surface of this flange and the inner periphery of the lower end of the cap. and the outer periphery of the cylindrical part of the nozzle via an O-ring below the seat surface. This seals the gap between the inner circumference of the cap and the cylindrical bottom of the nozzle from the bottom end of the cap. The structure is such that the end and the conical portion following it are exposed.

[0007]

[Effect]

According to the above configuration, conventionally only a part of the lower end of the nozzle is exposed and all other parts are exposed. The cap of the plasma torch, which was covered by the cap, is moved back upwards. The exposed length of the nozzle from the bottom of the cap has been lengthened, and the conical apex angle at the nozzle tip has been reduced. The lower end of the torch has a tapered shape, so the torch can be used when cutting uneven materials. The risk of the lower end of the reach hitting the material to be cut is drastically reduced. Also, since it is a tapered nozzle, The marking lines on the material to be cut are now easier to see than before, making robot teaching work easier. Work becomes easier.

[0008] Furthermore, seal the gap between the nozzle and the cap with an O-ring, and adjust the installation position of the O-ring. Since it is located above and away from the lower end of the torch, the sealing performance of the nozzle cooling water is significantly improved. Ru.

[0009]

【Example】

Refer to the drawings below for an example of the tapered nozzle of the plasma torch according to the present invention. This will be explained in detail. Figure 1 is a cross-sectional view of the tip of a plasma torch using a tapered nozzle according to the present invention. be. A flange 1a is provided on the upper outer circumference of the nozzle 1, and a flange 1a is provided below the flange 1a. The surface is in close contact with a seat surface 2a provided on the inner periphery of the cap 2, and the nozzle 1 and the cap 2, and is inserted into the nozzle 1 and the nozzle 1. Components such as an insulating cylinder 3, a swirler 4, and an electrode 5 are fixed to the torch body.

0010 A groove into which an O-ring is inserted is provided at the lower end of the cap 2, and an O-ring is inserted into this groove. The O-ring 6 is in close contact with the outer periphery of the nozzle 1 below the flange 1a to cool the nozzle. The cooling water flowing through the water passage 7 is sealed. The outer diameter of the cylindrical part at the top of nozzle 1 is It is larger than the outside diameter of the nozzle in the structure, but this is due to the increased wall thickness of the cylindrical part. It depends.

[0011] In this way, some of the functions of the cap, which were conventionally concentrated at the bottom end of the nozzle, can be integrated into the nozzle. Move the lower end of the nozzle upward, exposing the lower end of the nozzle 1 from the lower end of the cap 2, and Let the apex angle θ of the cone be the apex of the cone formed by the cap of a conventional plasma torch. Since it is smaller than the corner, the diameter of the lower end of the torch is thinner than before, and the shape is sharp. To give an example of the apex angle of the cone at the lower end of the torch, in a conventional plasma torch, 2, θ = 70°, but in the present invention, θ = 50°. Ru.

0012 By increasing the thickness of the cylindrical part of the nozzle 1 and installing the flange 1a, the heat of the nozzle 1 is reduced. Due to the increased conductivity and the increased exposed area of nozzle 1, the cooling performance of the nozzle has improved. improved. Therefore, the cooling water does not circulate from the upper surface of the flange 1a to the lower part. Despite this, overheating of nozzle 1 was not observed.

[0013] With the above improvements, the lower end of the torch remains covered even in valley-shaped concave areas of the material to be cut. The torch height does not touch the material to be cut and is therefore conventionally unavoidably larger than the prescribed distance. Even parts that were previously cut can be cut while maintaining a predetermined torch height. child This expands the cutting range and significantly improves cutting quality. Also, robot Even when teaching the cutting path for a material, the marking lines on the material to be cut are not the same as before. Since it is much easier to see than in comparison, teaching accuracy and work efficiency are improved.

[0014] Furthermore, since we decided to use an O-ring for the cooling water seal, the conventional nozzle Sealing performance is improved compared to seals made by metal contact with the cap and the cap, and there is no water leakage. It became. Also, because the nozzle fixing part of conventional caps is close to the lower end of the nozzle, Therefore, it is easy to cause molten metal adhesion during cutting work and abnormal discharge, i.e., double arc points. This damage can cause problems such as water leakage. Therefore, the cap I had to replace the pads frequently. In contrast, with the tapered torch of this invention, the cap The fixed part of the nozzle is located far from the lower end of the nozzle so that it is hidden from the molten metal that scatters during cutting. Because the cap is set in the position where it is placed, no damage to the cap occurs and the cap remains can be used.

[0015]

[Effect of the idea]

As explained above, according to the present invention, the cap that was concentrated at the lower end of the nozzle can be removed. Move the function to the top of the nozzle as much as possible, increasing the nozzle exposure length from the bottom edge of the cap. In addition, we reduced the conical apex angle at the nozzle tip and made the lower end of the torch tapered. Compared to conventional plasma torches, it is more effective in 3D cutting of materials with complex shapes. It also becomes possible to cut while maintaining a predetermined torch height. This results in In addition to improving cutting quality, it is also possible to expand the scope of cutting work. Become.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of the lower end portion of a plasma torch using a tapered nozzle.

FIG. 2 is a sectional view of a lower end portion of a conventional plasma torch.

[Explanation of symbols]

1 nozzle 1a Flange 2 Cap 2a Seat surface 5 Electrode 6 O-ring

Claims (1)

[Scope of utility model registration request] Claim 1: A flange is provided on the outer periphery of the upper cylindrical part of a nozzle that encloses an electrode and has a small hole at the lower end for ejecting a plasma arc, and a seat surface provided on the lower surface of the flange and on the inner periphery of the lower end of the cap. The gap between the outer periphery of the cylindrical part of the nozzle and the inner periphery of the cap is sealed below the seat surface via an O-ring, and the cylindrical lower end of the nozzle and the conical part following it are sealed from the lower end of the cap. The tapered nozzle of a plasma torch is characterized by an exposed nozzle.