JPS62238020A - Method and device for plasma type marking - Google Patents

Abstract

PURPOSE:To prevent defective marking and to make marking clear and uniform by connecting a plasma arc torch with a plasma electric power supply and melting the surface of a stock to be marked by a plasma arc gas. CONSTITUTION:The 1st pipe 14 for supply of a plasma gas and the 2nd pipes 17a and 17b for supply of cooling water are set inside a plasma arc torch 1 and an electrode 16 is adjacently placed to a spout hole 12 of a nozzle 13. The plasma gas supplied from the 1st pipe 14 is spouted into the atmosphere through a flow straightener 15. In that time, the plasma gas whose energy concentrates to the central part spouts when plasma arcs are generated between the electrode 16 and the nozzle 13. The marking is performed by melting the surface of a stock 7 to be marked by that gas. In that method, defective marking is eliminated and the marking is made to be clear and uniform because of no use of powders.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Field of Application> The present invention relates to an old plasma method for marking lines, characters, symbols, etc. on the surface of a steel plate, and an apparatus for carrying out the method.

<Prior art> Conventionally, when writing lines or letters on the surface of a steel plate, a type of gas cutting crater is used, metal or synthetic resin powder is supplied to the jet nozzle of this crater, and the powder existing around it is used. It was common practice to melt the powder using a flame, and then weld and mark the powder onto the surface of the steel plate.

<Problems to be solved by the invention> In the conventional methods and devices described above, it is necessary to always supply powder smoothly, but in reality powder clogs the supply hose, piping, etc. This has the drawback that the conveyance of the powder becomes unstable, making it impossible to determine the marking line at all, or that the line is not constant.

On the other hand, the speed of the machine that moves the marking device varies between curved corners and straight sections of the figure to be scribbled, so even if powder supply is smooth and constant, the line 11 will become thicker. There was a drawback.

Furthermore, if metal is used as the powder, molten powder may accumulate on the steel plate at the start and end, and when the steel plate is cut in the subsequent process, there is a risk that it will not be possible to cut the part where this molten substance has accumulated. was there.

The method and device according to the present invention is a completely new technology developed to overcome these drawbacks of the conventional technology, and it is possible to mark a steel plate without using all the powder that causes problems in bamboo. The aim is to provide a device that can do this.

<Means for Solving the Problems> The present invention jets plasma arc gas onto a material to be marked from the nozzle of a plasma arc torch, melts the surface of the material to be marked, and thereby writes lines, characters, figures, etc. The present invention relates to a plasma marking method and a plasma marking device for implementing this method.

As mentioned above, the present invention uses a non-transfer type plasma arc in a thin and concentrated manner to heat and melt the surface of the marking material to continuously form an extremely thin marking line. is completely unnecessary, therefore, the above-mentioned drawbacks due to the use of powder can be fundamentally improved.Moreover, even if the marking speed changes at a corner etc., the marking line is formed as an extremely thin line, so it is possible to The thickness of the marking line hardly changes, and it is possible to always obtain a constant and highly accurate marking line.

<Example> An example of the apparatus according to the present invention will be specifically described as follows. In FIGS. 1 to 3, ``■'' is a marking plasma torch used in the present invention, and is connected to a non-transfer type plasma torch AY 2 via a hose 3. Reference numeral 4 denotes a marking machine that can run on rails 5, and a torch carriage 6 that can hold and move the torch 1 is slidably attached to this machine body 4. Reference numeral 7 denotes a material to be marked (a steel plate), on the surface of which a marking pad 8 is perforated by the torch 1, and the material to be marked 7 is placed on a surface plate 9.

Next, to specifically explain the plasma torch for marking used in the apparatus of the present invention, torch I is particularly
As shown in the figure, a torch outer cylinder 10 is provided on the outer periphery, a protective cap 11 is provided on the outer periphery of the tip, and a plasma arc gas nozzle having a small diameter of 1.51 mm or less in the center at the leading edge. Arc jet nozzle 1 having 12
3 is installed.

Further, a first pipe 14 capable of supplying plasma gas is provided at the center of the torch I, and this first pipe 14 is electrically connected to an electrode.

Furthermore, a plasma gas rectifier 15 and an electrode 16 whose lower end is adjacent to the ejection hole 12 of the nozzle 13 are provided at the lower end of the first pipe 14, respectively. Moreover, the first pipe 1
Around 4, there is a second pipe +7a, I, which is electrically connected to the nozzle I3 and can circulate cooling water.
7b is provided and these second pipes 17a, 1
7b is a water cooling chamber 1 provided around the nozzle 13
It is connected to 8. Furthermore, an insulator 19 is provided between the first pipe 14 and the second vibrator 17a, 17b. Further, 20 is an electrode holder for attaching the electrode 16 to the torch.

Next, a specific example of carrying out the method of the present invention using the apparatus according to the present invention will be described. Plasma gas supplied from the first pipe 14 passes through the plasma gas rectifier 15 and flows from the vicinity of the electrode 16 to the ejection hole 12 of the nozzle 13. is ejected into the atmosphere through the When the power is turned on at this time, an arc is generated between the electrode 16 and the nozzle 13, and the plasma gas is ejected in a plasma state. Garth that has been turned into plasma in this way is cooled by the action of the water cooling chamber 18 provided around the nozzle 13, so when it passes through the ejection hole 12 of the nozzle 13, energy is transferred to the center due to the thermal pinch effect. It is concentrated and ejected.

Therefore, while ejecting the plasma gas in this way from the ejection hole 12 of the nozzle 13, it is transferred to the material to be marked 7.
When the surface of the marking material 7 is applied to the surface, the surface of the marking material 7 melts into a thin line, and this molten part is heated and cooled to form a color that blends with the surrounding area, forming a thin marking line 8. As a result of various experiments regarding the diameter of the marking line 8, the present inventor found that the thinner the marking cotton 8, the easier it is to see.In order to make the marking line 8 thinner, the plasma ejected from the nozzle 13. It has been discovered that the smaller the diameter of the gas is, the better it is, and that in order to further reduce the diameter of the plasma gas, the diameter of the ejection hole 12 of the nozzle 13 needs to be 1.5 mm or less.

<Effects of the Invention> Since the method according to the present invention has the above-described structure and operation, unlike the conventional method using marking powder, it is possible to avoid marking defects due to powder clogging, etc. and subsequent cutting defects. It is possible to completely prevent the occurrence of marking lines, and also to prevent the marking lines from becoming thick in some corners, etc., and it is possible to always make the desired clear and uniform markings, thereby reducing the possibility of subsequent misreading. It is possible to completely eliminate work errors, and furthermore, the method of the present application has a melting point of 2.
It can be applied to any material to be marked with a temperature of 000℃ or less, and it can be applied easily and easily to materials with different melting points by changing the current level. It exists.

[Brief explanation of drawings]

FIG. 1 is an enlarged sectional view of a part of the device according to the present invention, and FIGS. 2 and 3 are perspective explanatory views showing the usage state and essential parts of the device of the present invention, respectively. 1 is a plasma torch, 2 is a plasma power source, 6 is a torch carriage, 8 is a marking line, 12 is an ejection hole, 13 is a nozzle, 14.17a, 17b are pipes, 15 is a rectifier, 16 is an electrode, and 18 is a water cooling chamber. be. Patent Applicant Koike Sanso Kogyo Co., Ltd. Agent Patent Attorney Shukichi Nakagawa Figure 1 Figure 2

Claims (2)

[Claims] (1) A plasma marking method characterized by ejecting plasma arc gas onto a material to be marked from a nozzle of a plasma arc torch and melting the surface of the material to be marked to draw lines, characters, figures, etc. (2) It has a first pipe for plasma gas supply, a second pipe for cooling water supply, a plasma gas rectifier, an electrode, a water cooling chamber, etc. inside, and a plasma arc gas ejection hole of 1.5 mm or less at the tip. 1. A plasma marking device comprising a plasma arc torch equipped with a nozzle connected to a plasma power source.