JPH10216949A - Plasma cutting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prolong the life of a nozzle and to enhance working efficiency for plasma cutting by making easily selectable either piercing or cutting and thereby using a different nozzle depending on the operation of piercing or cutting. SOLUTION: The plasma cutting device is such that either piercing or cutting can be easily selected for example by inputting through a key board, that a used nozzle is used if piercing only is then selected while a fresh nozzle is used if cutting only, and that therefore the life of the fresh nozzle can be essentially prolonged because it receives less damage. In addition, since no nozzle with damage received due to piercing is used as is for cutting, it improves cutting quality. Further, a nozzle with a prolonged life also contributes to saving in expenses for consumables.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma cutting apparatus, and more particularly to a plasma cutting apparatus capable of arbitrarily selecting piercing and cutting.

[0002]

2. Description of the Related Art Conventionally, a plasma torch 10 used in a plasma cutting process has, for example, a case 11, an electrode 12, and a nozzle 13 as shown in FIG.

[0003] With this configuration, the plasma arc 14 emitted from the electrode 12 is sprayed onto the work W through the nozzle 13, and the work W is subjected to a predetermined plasma cutting process.

However, when performing plasma cutting from the inside of the work W, first, as shown in FIG.
As shown in (C), by cutting the plasma torch 10 (in the direction of the arrow), the C region on the work W is cut.

[0005] That is, when performing the plasma cutting process from the inside of the work W, the process is a piercing process (FIG. 4 (B)),
It consists of two cutting steps (FIG. 4C).

Conventionally, in both of these steps, the same nozzle 13 is used to perform a plasma cutting process from the inside of the work W.

[0007]

However, the degree of wear of the nozzle 13 is more intense in the piercing step (FIG. 4B) among the above two steps, and the spatter 15 generated from the work W is scattered. Then, if it adheres to the nozzle 13, the nozzle 13 is damaged and cannot maintain a normal plasma arc.

In general, based on the work W,
The height a of the plasma torch 10 at the time of the piercing step (FIG. 5A) is different from that of the plasma torch 1 at the time of the cutting step.
By setting the height to be greater than the height b (FIG. 5B), the scattering of the spatter 15 from the work W is avoided (FIG. 5A).

The operation of switching the height of the plasma torch 10 in this case is controlled by an NC or the like when the process shifts from the piercing process to the cutting process.

However, when the process shifts to the cutting process, as shown in FIG. 5C, the melted work generated in the piercing process, that is, the noro 16 may come into contact with the nozzle 13 at the tip of the plasma torch 10. .

In such a case, the arc current is
2 flows to the work W via the nozzle 13 and the nozzle 16 (FIG. 5 (E)), and causes great damage to the nozzle 13.

That is, normally, the plasma arc 14 jetted from the electrode 12 is jetted straight toward the workpiece W (FIG. 5 (D)), but not jetted to the nozzle 13 side.

However, when the nozzle 13 comes into contact with the barb 16 (FIGS. 5 (C) and 5 (E)), the plasma arc 14 is not straight, but is bent and ejected toward the nozzle 13 to form a double arc. Phenomena, and as a result, the nozzle 1
Causes massive damage to 3.

On the other hand, during cutting (FIG. 4C)
Does not fly so much that spatter gives damage to the nozzle 13 and the height of the plasma torch 10 is adjusted (FIG. 5).
(A), FIG. 5 (B)), if accurate, a double arc (FIG. 5 (E)) is less likely to occur, and the life of the nozzle 13 depends solely on the number of piercing operations.

However, conventionally, as described above, since the same nozzle 13 is used for piercing and cutting, the life of the nozzle 13 is short.

That is, the nozzle 13 is used for piercing,
If it causes severe damage, it cannot be used for cutting afterwards.

In order to solve this problem, it has been proposed to provide a drill or a punch for piercing in a plasma cutting apparatus.

First, the work W is pierced by using such a drill or a punch.
Next, the cutting process was performed by using the nozzle 13.

However, it is not preferable to add a drill or a punch for piercing to the plasma cutting apparatus, because it is troublesome and time-consuming, and therefore increases the cost.

An object of the present invention is to extend the life of a nozzle by making it possible to easily select either one of piercing and cutting and using different nozzles during piercing and cutting. It is to improve the processing efficiency of plasma cutting.

[0021]

In order to solve the above problems SUMMARY OF THE INVENTION The present invention, in addition to the conventional processing method, a only one of the cutting and piercing selectable only piercing is If selected, pierce the work using a used plasma torch with a nozzle, and if only cutting is selected, use a plasma torch with a good nozzle. Technical measures are taken to cut the steel.

Therefore, according to the structure of the present invention, the work W
When plasma cutting is performed from the inside of the
(A)) First, only piercing is selected by keyboard input (FIG. 1) (step 10 in FIG. 3).
1) The workpiece W is pierced using an old nozzle that cannot be used for cutting (FIG. 2)
(B)) Then, only the cutting process is selected by keyboard input (FIG. 1) (step 10 in FIG. 3).
3) Since the workpiece W can be cut using a new or good nozzle which is not damaged (FIG. 2).
(C)) A good nozzle is less likely to be damaged, and the present invention works to extend the life of the nozzle as a whole.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the accompanying drawings according to embodiments. FIG. 1 is a diagram showing an embodiment of the present invention.

The plasma cutting apparatus shown in FIG. 1 comprises a keyboard 1, a CPU 2, a storage unit 3, an NC 4, and a processing unit 5.

The keyboard 1 outputs a signal S1 corresponding to whether only piercing is selected or only cutting is selected.
(FIG. 1), for example, using a numeric keypad or the like.

The CPU 2 determines a sequence such as piercing based on the input signal S1 from the keyboard 1 (step 102 in FIG. 3) and transmits a control signal S3 corresponding to the sequence to the NC 4 in the next stage. I do. Others
The CPU 2 controls the entire apparatus shown in FIG.

The storage unit 3 temporarily stores a product program and parameters input from the keyboard 1 and
2 reads the product program and parameters (signal S2 in FIG. 1) to determine the sequence.

The NC 4 numerically controls a processing unit 5 described later based on the control signal S 3 transmitted from the CPU 2.

The processing section 5 performs piercing on the work W (see FIG. 2).
(B)), a cutting process (FIG. 2 (C)), and a plasma torch to perform a normal process (step 105 in FIG. 3).

Hereinafter, the operation of the present invention having the above configuration will be described.
A description will be given based on FIG. 2 and FIG.

In this case, the product to be processed by the plasma cutting apparatus (FIG. 1) according to the present invention is, for example, as shown in FIG.
Product A having the shape shown in (A) and having circular holes A1 and A2, and product B having circular holes B1 and B2.
It is.

In this case, as apparent from FIG. 2A, in order to process the products A and B, it is necessary to perform a plasma cutting process from the inside of the work W.

Therefore, first, the piercing hole P
It is necessary to perform only the piercing processing for opening 1 and the like (FIG. 2 (B)), and then to perform only the cutting processing for cutting along the cutting line C1 and the like (FIG. 2 (C)).

Hereinafter, the procedure in this case will be described in detail.

(1) First, only piercing is first selected.

Specifically, for example, when a key "1" indicating that only piercing is selected is pressed from the keyboard 1 shown in FIG.
Input to U2.

(2) Next, the used nozzle is set on the plasma torch.

That is, the piercing hole P1 and the like (FIG. 2B)
Since a nozzle that cannot be used for cutting can be processed, an old-fashioned nozzle is set on a plasma torch.

(3) Next, when a product program and parameters as processing conditions are input from the keyboard 1,
The product program and the parameters are temporarily stored in the storage unit 3 (signal S2 in FIG. 1).

(4) Next, the CPU 2 determines that only piercing is selected (Y in step 101 in FIG. 3).
ES), the product program and the parameters are read from the storage unit 3 (signal S2 in FIG. 1), and the piercing processing sequence is determined (step 102 in FIG. 3).

For example, piercing holes P1, P2, P3 (FIG. 2)
The two-dimensional coordinates of (B)) are expressed as (X ₁ , Y ₁ ), (X
₂ , Y ₂ ) and (X ₃ , Y ₃ ).

In this case, in the piercing sequence, the plasma torch is set at the coordinates (X ₁ , Y ₁ ), (X ₂ ,
Y ₂ ) and (X ₃ , Y ₃ ), and include an operation sequence and a machining command sequence in which an arc is ejected from the used nozzle onto the work W to open the piercing holes P1, P2, and P3.

This means that the pierced holes P4, P5, P6
The same applies to (FIG. 2B).

(5) The CPU 2 transmits the above-described piercing processing sequence to the NC 4 at the next stage as a control signal S3 (Step 106 in FIG. 3), and the NC 4 causes the processing section 5 to perform numerical processing according to the piercing processing sequence. By controlling, the piercing hole P1 and the like as shown in FIG.
(Step 107 in FIG. 3).

Thereafter, the operator determines whether or not all the processing has been completed (step 108 in FIG. 3). In the present embodiment, since the processing has not been completed (NO), the operator returns to the first procedure (step 108). Step 101 in FIG. 3).

Here, the already described double arc (FIG. 5)
In order to prevent (E), before moving to the cutting step, the sticks on the work generated in the piercing step are manually removed.

(6) Next, only the cutting process is selected.

More specifically, for example, when a key "2" indicating that only piercing is selected is pressed from the keyboard 1 shown in FIG.
Input to U2.

(7) Next, the used nozzle used for piercing is removed from the plasma torch, and a good nozzle is set.

(8) Next, the CPU 2 determines whether only piercing is selected (step 101 in FIG. 3),
Further, it is determined whether only the cutting process is selected (FIG. 3).
Step 103).

In this case, as described in the above (6),
Since only the cutting process has been selected, the CPU 2 determines that only the cutting process has been selected (step 103 in FIG. 3).
YES), the product program and the parameters are read from the storage unit 3 (signal S2 in FIG. 1), and a cutting processing sequence is determined (step 104 in FIG. 3).

For example, the cutting line of the product A is denoted by C1, C2, C
3 (FIG. 2C).

In this case, the cutting process sequence is as follows: the piercing hole P1 extends along the cutting line C1, the piercing hole P2 extends along the cutting line C2, and the piercing hole P3 extends the cutting line C.
3 includes an operation sequence of cutting an arc by injecting an arc from a good nozzle onto the work W while moving the plasma torch, and a machining command sequence.

This also applies to the product B (FIG. 2).
(C) cutting line C4, C5, C6).

(9) The CPU 2 transmits the above-described cutting processing sequence to the NC 4 at the next stage as a control signal S3 (Step 106 in FIG. 3). By performing the control, a cutting process as shown in FIG. 2C is performed on the work W (Step 107 in FIG. 3).

Thus, the product A having the circular holes A1 and A2 as shown in FIG.
The product B in which B2 is open is processed.

Thereafter, the operator determines whether or not all the processing has been completed (step 108 in FIG. 3). If it is determined that the processing has been completed (YES), the operation of the apparatus in FIG. 1 is terminated. (END in FIG. 3).

However, if it is not desired to divide the piercing step and the cutting step, that is, if it is desired to perform the piercing and the cutting in one step as in the prior art, in step 105 of FIG. The sequence is determined and is set via NC4 (step 10 in FIG. 3).
6) The cutting process is performed by the processing unit 5 after the piercing (step 107 in FIG. 3).

As described above, according to the present embodiment, when only the piercing is selected, the used nozzle is set on the plasma torch and only the cutting is selected, as described in (2) above. If so, a good nozzle was set on the plasma torch as described in (7) above.

However, the present invention is not limited to this,
For example, the following means can be taken.

That is, for example, by using an auto tool changer, when only piercing is selected, used nozzles are used, and when only cutting is selected, good nozzles are used.

For example, when only piercing is selected, a plasma torch dedicated to piercing with used nozzles is used. When only cutting is selected, cutting with a good nozzle is used. Use different plasma torches for processing.

By these means, the products A and B are processed (FIG. 2A) by the procedures shown in FIGS.

[0064]

As described above, according to the present invention, it is possible to select only one of the piercing process and the cutting process for the plasma cutting device, and when only the piercing process is selected, If the workpiece is pierced using a used plasma torch with a nozzle, and if only cutting is selected, the workpiece should be cut using a plasma torch with a good nozzle. Configured.

Accordingly, first, for example, either one of piercing and cutting can be easily selected by keyboard input (FIG. 1). Next, when only piercing is selected, the worn-out When a nozzle is used and only the cutting process is selected, a good nozzle is used, so that there is an effect that the life of the nozzle can be substantially extended.

Further, since the nozzle damaged by the piercing process is not used as it is for the cutting process, there is an effect that the cutting quality is improved.

Further, since the life of the nozzle can be extended, there is an indirect effect that the cost of consumables can be reduced.

[0068]

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a diagram illustrating the operation of the present invention.

FIG. 3 is a flowchart illustrating the operation of the present invention.

FIG. 4 is an explanatory diagram of a conventional technique.

FIG. 5 is an explanatory diagram of a problem in the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Keyboard 2 CPU 3 Storage part 4 NC 5 Processing part

Claims (5)

[Claims] 1. The method according to claim 1, wherein only one of piercing and cutting is selected. When only piercing is selected, the workpiece is pierced using a used plasma torch with a used nozzle. A plasma cutting apparatus, wherein a workpiece is cut using a plasma torch provided with a good nozzle when only cutting is selected. 2. A keyboard, a CPU, a storage unit, and N
When only piercing or only cutting is selected by the keyboard, CP
U determines a piercing processing sequence or a cutting processing sequence and sends it to the NC. Under the control of the NC, the processing section pierces the workpiece using a used plasma torch with a used nozzle. The plasma cutting apparatus according to claim 1, wherein the workpiece is cut using a plasma torch provided with a good nozzle. 3. When only piercing is selected,
2. The plasma cutting apparatus according to claim 1, wherein the used nozzle is attached to the plasma torch, and if only cutting is selected, a good nozzle is attached to the plasma torch. 4. The automatic tool changer according to claim 1, wherein when only piercing is selected, used nozzles are used, and when only cutting is selected, good nozzles are used. Plasma cutting equipment. 5. When only piercing is selected,
2. The plasma cutting apparatus according to claim 1, wherein a dedicated plasma torch provided with an old nozzle is used for piercing, and a dedicated plasma torch provided with a good nozzle is used when only cutting is selected.