JP2000107862A - Thermal cutting method and its device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate cleaning for a torch and a torch holder and an adjustment for a collision detector and to lessen an invasion of noises into a controller by simplifying a structure around the torch. SOLUTION: A torch 3 is inserted into a torch inserting hole 17 of a torch holder 5. A torch supporting part 19 which is provided in the outer periphery of the torch 3 is freely brought into contact with or separated from the upper surface of the torch holder 5. A movement of the torch supporting part 19 when the torch 3 collides is transmitted to a lever 35 capable of freely rocking which is provided in a machine main body with a power transmission device and sensed with a collision detector 27. The power transmission device is composed of a tubular coat part 31 and a power transmission wire 33 which is inserted through the coat part, one end of the coat part 31 is attached to the torch supporting part 19 and the other end of the coat part 31 is attached to a torch collision detecting part 23. The power transmission wire 33 and the coat part 31 are energized with an energizing means in the relatively separating direction so that the torch supporting part 19 is always brought into press- contact with the torch holder 5, and the torch 3 is protected without being damaged by the energizing force even though the torch 3 collides with an obstacle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for hot cutting.

[0002]

2. Description of the Related Art Conventionally, for example, a plasma processing machine 101 as a thermal cutting machine has a work table on which a work W is placed. The torch 103 for thermally cutting the work placed on the work table is held by a torch holder 105 as shown in FIG. The torch holder 105 has an L-shaped cross section composed of a vertical bracket portion 107 and a horizontal holder portion 109.
The torch holder 105 is attached to an elevating drive unit provided in the torch head 111 and is provided so as to be able to move up and down.

[0003] The torch head 111 is provided on the carrier so as to be movable in the left-right direction, and the carrier is provided above the work table so as to be movable in the front-rear direction. The torch 103 is placed on the worktable in the X-axis direction and the Y-axis direction,
It can be moved and positioned in the Z-axis direction.

A torch insertion hole 11 through which the torch 103 can be inserted is provided substantially at the center of the holder portion 109 of the torch holder 105.
3 are provided, and a plurality of shaft insertion holes 115 are provided around the torch insertion hole 113.

As shown in FIG. 5, a flange-shaped torch support portion 117 is integrally formed on the outer periphery of the torch 103 so as to protrude therefrom. The lower surface of the torch support portion 117 is placed on the upper surface of the holder portion 109 of the torch holder 105 in a state where the torch 103 is inserted into the torch insertion hole 113 of the torch holder 105 from the tip side.

Further, a plurality of spring shafts 119 provided in the torch support portion 117 project downward through the shaft insertion holes 115 of the holder portion 109, and a spring receiving plate provided at a lower end of the spring shaft 119. A spring 123 is provided between the holder 121 and the torch support 1.
17 is urged so as to be constantly pressed against the upper surface of the holder portion 109.

Therefore, during plasma processing, the torch 10
When the object 3 collides with the obstacle D, the torch 103 is inclined and the torch support part 117 is separated from the upper surface of the holder part 109 of the torch holder 105 as shown in FIG. Torch 10
Since no excessive force is applied to 3, the torch 103 is protected without being damaged.

The torch support section 117 is provided with a limit switch LS for detecting the upper surface of the holder section 109 as shown in FIG. The limit switch LS is a collision detector 125 that detects when the torch support portion 117 has separated from the upper surface of the holder portion 109, that is, detects that the torch 103 has collided.

[0009]

However, in the conventional thermal cutting machine, a plurality of springs 123 and a collision detector 125 are provided around the torch 103, which is complicated. There was a problem.

(1) Holder section 109 of torch holder 105
In order to remove dust and dust between the torch 103 and the torch support portion 117 of the torch 103, it is necessary to disassemble the members such as the plurality of spring shafts 119 and the springs 123, which is troublesome.

(2) Since the periphery of the torch 103 is complicated, it is not easy to adjust the distance between the tip of the collision detector 125 and the upper surface of the holder 109.

(3) Since a protection mechanism such as a cable bear for protecting the lead wire e of the collision detector 125 is required, the cost increases.

Further, since electrical components such as the collision detector 125 are located near the torch 103, there is a concern that noise from the torch 103 generated during plasma processing may enter the control device via the collision detector 125. There was a point.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has as its object to simplify the structure around the torch to facilitate cleaning of the torch and the torch holder, and to facilitate adjustment of the collision detector. An object of the present invention is to provide a thermal cutting method and an apparatus therefor that can reduce the intrusion of noise.

[0015]

According to a first aspect of the present invention, there is provided a thermal cutting method according to the present invention, wherein a torch is inserted into a torch insertion hole of a torch holder provided in a machine body, and the torch is inserted into the torch. Urging the torch support portion provided on the outer periphery of the torch holder so as to constantly press against the upper surface of the torch holder,
By transmitting the movement of the torch support portion when it collides with the torch and tilts to a movable detection target member provided on the machine main body by a power transmission device, and detects the operation of the detection target member by a collision detector. The present invention is characterized in that it detects that the torch has collided.

Accordingly, the torch support portion is normally biased so as to be in pressure contact with the torch holder, but can be freely moved in and out of contact with the torch holder. Even if the torch collides with an obstacle, the torch is tilted without being damaged. Protected. Moreover,
When the torch collides with an obstacle, the torch support is inclined and separates from the torch holder, so that the movement of the torch support is transmitted by the power transmission device and the detected member moves. The operation of the detected member is detected by the collision detector, and the collision of the torch is detected.

Since the collision detector is not provided around the torch, the periphery of the torch is simplified, so that the collision detector can be easily adjusted, and noise caused by the torch is controlled via the collision detector as in the conventional case. The situation of invading the device is eliminated. Accordingly, inexpensive general-purpose detectors are used as collision detectors.

According to a second aspect of the present invention, there is provided a thermal cutting apparatus according to the present invention, wherein a torch holder having a torch insertion hole for inserting a torch to be thermally cut into a work is provided on a machine body, and a torch support is provided on an outer periphery of the torch. A collision detector is provided, which is provided so as to be able to contact and separate from the upper surface of the torch holder and is urged in a direction in which the torch holder is constantly pressed against the torch holder. The collision detector includes a movable detection target member and detects an operation of the detection target member. A torch collision detection unit is provided on the machine body, and a power transmission device for transmitting the movement of the torch support unit to the detected member is provided.

Therefore, the operation is similar to that of the first aspect, and the torch support portion is normally urged so as to be pressed against the torch holder, but is freely movable. The torch is protected because the torch tilts without breaking. In addition, when the torch collides with an obstacle, the torch support is inclined and separates from the torch holder, so that the movement of the torch support is transmitted by the power transmission device and the detected member moves. The operation of the detected member is detected by the collision detector, and the collision of the torch is detected.

Since the collision detector is not provided around the torch, the surroundings of the torch are simplified, so that the collision detector can be easily adjusted, and the noise caused by the torch is controlled via the collision detector as in the prior art. The situation of invading the device is eliminated. Accordingly, inexpensive general-purpose detectors are used as collision detectors.

According to a third aspect of the present invention, there is provided a thermal cutting apparatus according to the second aspect, wherein the power transmitting device comprises a tube-shaped coating portion and a power transmitting wire passing through the inside of the coating portion. And the detected member is constituted by a swingable lever, one end of the coat portion is attached to the torch support portion, and the other end of the coat portion is attached to the torch collision detection portion, and the power transmission is performed. One end of the wire is attached to the torch holder, and the other end of the power transmission wire is attached to the lever, and the power transmission wire and the coating portion are biased by the urging means so that the torch support portion of the torch is constantly pressed against the torch holder. It is characterized in that it is provided so as to be biased in a direction in which it is relatively separated.

Therefore, since the coat portion and the power transmission wire are urged in a direction in which they are relatively separated from each other, the torch support portion is urged so as to always press against the torch holder. The torch is protected from damage in the event of a collision. In addition, when the torch collides with an obstacle, the torch support portion is inclined and separates from the torch holder, so that the power transmission wire is pulled against the biasing direction and the lever swings. The operation of the lever is detected by the collision detector, and the collision of the torch is detected.

According to a fourth aspect of the present invention, there is provided a thermal cutting apparatus according to the second or third aspect, wherein a plurality of the power transmission devices are disposed at substantially symmetric positions around a torch. It is characterized by the following.

Therefore, since the plurality of power transmission devices are provided at substantially symmetrical positions around the torch, even if the torch support is slightly separated from the torch holder due to the collision of the torch, at least one power transmission device is used. The movement of the torch support is transmitted to the lever, and the torch collision is detected sensitively.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a thermal cutting apparatus according to the present invention will be described below with reference to the drawings using a plasma processing machine as an example.

Referring to FIG. 1, as a plasma processing machine 1 according to the present embodiment, for example, a work table (not shown) on which a work W is placed is provided.

A torch holder 5 for holding a plasma torch 3 (hereinafter simply referred to as a "torch") for thermally cutting a work W placed on a work table is movable up and down on a torch head 7 as a machine body. The torch head 7 is provided on a carrier (not shown) so as to be movable in the left-right direction, and the carrier is provided above the work table so as to be movable in the front-rear direction.

Therefore, the torch 3 can be moved and positioned on the work table in the X-axis direction, the Y-axis direction, and the Z-axis direction.

At the tip of the torch 3, there is provided a nozzle 9 for irradiating a plasma jet toward the work W.

More specifically, the plasma processing machine 1 has a built-in DC welding power source and a high-frequency generation source (not shown) for generating a plasma jet. The gas is heated to a high temperature by the arc heat generated by the torch 3 by the DC welding power source or the high-frequency generation source, and becomes a plasma. The plasma gas, that is, the plasma jet is jetted from the nozzle 9 and cut into a desired shape. Plasma processing such as is performed.

As the plasma processing machine 1, the torch head 7 provided with the torch holder 5 so as to be able to move up and down is provided on the main body frame in the left-right direction (Y-axis direction). It may be provided so that it can be moved and positioned in the front-rear direction (X-axis direction). Alternatively, the torch holder 5 is provided on the main body frame so as to be able to move up and down, and a clamp device for gripping the work W is provided on the work table so as to be movable and positionable in the front-rear and left-right directions (X-axis and Y-axis directions). I do not care.

Next, the torch collision detection device 11 in the plasma processing machine 1 showing the main part of the embodiment of the present invention will be described in detail.

Referring to FIG. 1, the torch holder 5 has an L-shaped cross section including a vertical bracket 13 and a horizontal holder 15. The torch holder 5 is provided with a plurality of bolts BT via a bracket 13 on a lifting drive (not shown) provided on a torch head 7 as a machine body, for example.
The holder portion 15 forming a horizontal piece is provided with a torch insertion hole 17 through which the torch 3 can be inserted.

A torch support portion 19 having a flange shape is integrally provided on the outer periphery of the torch 3. The lower surface of the torch support portion 19 and the holder portion 15 of the torch holder 5 are provided.
Are provided with fitting portions 21 that fit each other.

Therefore, with the torch 3 inserted through the torch insertion hole 17 of the torch holder 5 from the tip end side,
The torch support portion 19 is stably mounted on the upper surface of the holder portion 15 of the torch holder 5 by the fitting portion 21, but the torch support portion 19 of the torch 3 is attached to the holder portion 15 of the torch holder 5.
It is freely movable toward and away from.

On the other hand, the torch head 7 as the machine main body is provided with a plate-like detecting section support member 25 having a torch collision detecting section 23. Torch collision detector 2
3 is provided with a collision detector 27 such as a limit switch LS for detecting that the torch 3 has collided with the obstacle D on the work table.

The movement of the torch support 19 is detected by the collision detector 27.
For example, a power transmission cable 29 is provided between the torch collision detection unit 23 and the torch support unit 19 as a power transmission device for transmitting the power to the motor. A power transmission wire 33 (hereinafter simply referred to as “wire”) is inserted.

More specifically, one end of a tube-shaped coat portion 31 is attached to the torch support portion 19, and the other end of the coat portion 31 is attached to the detection portion support member 25. Moreover, the wire 3 inserted through the coat portion 31
One end of 3 is attached to the holder 15 of the torch holder 5, and the other end of the wire 33 is attached to, for example, a lever 35 as a member to be detected. The lever 35 is swingably provided on the detection unit support member 25. The details of the mounting structure of the lever 35 and the wire 33 will be described later.

In this embodiment, one end of the power transmission cable 29 is symmetrical with respect to the torch insertion hole 17 at a position symmetrical with respect to the torch support portion 19 and the holder portion 15.
Attached to. However, the power transmission cable 29
The number is not limited to the above-mentioned two, but a plurality can be provided. Preferably, the number is attached to the torch support portion 19 and the holder portion 15 at a position symmetrical about the torch 3.

As shown in FIGS. 1 and 2, the torch support 19 is provided with a coat mounting hole 37 for attaching one end of the coat 31 of the power transmission cable 29, through which the wire 33 is inserted. A possible wire groove 39 is provided to communicate with the outer peripheral surface of the torch support 19 from the coat mounting hole 37.

As shown in FIG. 2, the holder portion 15 is provided with a wire mounting hole 41 for mounting one end of the wire 33 of the power transmission cable 29 in the same manner as the coating portion mounting hole 37. , The above-mentioned torch support 19
Similarly to the above, a wire groove portion 43 through which the wire 33 can be inserted is provided so as to communicate from the coat portion mounting hole 37 to the outer peripheral surface of the torch support portion 19.

Referring to FIG. 1 again, the torch collision detector 23 includes a wire stopper 45 for stopping the ends of the plurality of wires 33 and a shaft 47 for moving the wire stopper 45. 1 is provided movably in the left-right direction in FIG. 1, and the wire 3 of the two power transmission cables 29 described above is provided.
One end of 3 is attached to a wire stopper 45.

The torch collision detector 23 has a lever 3
1 is provided so as to be swingable in the left-right direction in FIG. 1, and the distal end of the shaft portion 47 of the wire operating member 49 is attached to the intermediate portion of the lever 35 in the longitudinal direction so as to be adjustable.

Further, the torch collision detector 23 is provided with, for example, a spring 51 as urging means for urging the wire 33 rightward by pressing the lever 35 rightward in FIG. In other words, the above wire 3
The torch 3 and the coat portion 31 are constantly urged in a direction in which they are relatively separated from each other by a spring 51, so that the torch support portion 19 of the torch 3 is constantly pressed against the holder portion 15 of the torch holder 5.

The torch collision detector 23 has a lever 3
For example, a limit switch LS as a collision detector 27 for detecting that the torch 3 has collided with the obstacle D by detecting the operation of No. 5 is attached. In the present embodiment, the limit switch LS is configured to be detected by being pressed by the tip of the lever 35 and to detect that the limit switch LS is disengaged from the limit switch LS even if the lever 35 swings in either of the left and right directions. .

When the torch 3 collides with the obstacle D as shown in FIG. 3, the wire 33 is pulled, so that the lever 35 moves in the direction A in FIG. The biasing force of the spring 51 moves the lever 35 in the direction B in FIG.

The shaft portion 4 of the wire operating member 49
Length from the position where 7 is attached to the tip of the lever 35
Is changed, the swing width of the tip of the lever 35 is changed, so that the sensitivity of the limit switch LS can be changed.

With the above configuration, when the torch 3 collides with the obstacle D during the plasma processing of the workpiece W, as shown in FIG. 3, the torch support 19 is tilted and a part of the torch support 19 is The wire 33 is pulled to separate from the holder part 15 of the torch holder 5.

The torch support portion 19 is normally urged so as to be in pressure contact with the holder portion 15 of the torch holder 5, but can be freely moved away from the torch, so that even if the torch 3 collides with the obstacle D, the torch 3 is damaged. Since the torch 3 is tilted without performing, the torch 3 is protected.

When the wire 33 is pulled, the wire operating member 49 is moved to the left in FIG. 1, so that the lever 35 swings in the direction A in FIG.
Is off from the limit switch LS. Therefore, the collision of the torch 3 with the obstacle D can be detected by the OFF signal of the limit switch LS.
By this detection signal, for example, the movement of the torch head 7 and the carrier for moving the torch 3 in the X-axis and Y-axis directions is stopped, and further, the torch 3 is moved in a direction opposite to the moving direction before the collision. And the torch support 19 is returned to the original position.

By providing another limit switch that can contact the lever 35 swinging in the direction B in FIG. 1, for example, the OF of the above-described limit switch LS is provided.
It can be determined whether the F signal is due to the breakage of the wire 33 or the collision of the torch 3.

Since the collision detector 27 such as the limit switch LS is not provided around the torch 3 unlike the related art, the periphery of the torch 3 is simplified, and the adjustment of the collision detector 27 is easily performed. Along with this, it is possible to avoid a situation in which noise from the torch 3 enters the control device via the collision detector 27 as in the related art, so that an inexpensive general-purpose detector can be used as the collision detector 27.

The present invention is not limited to the above-described embodiment, but can be embodied in other forms by making appropriate changes.

For example, the position of the spring 51 in the above-described embodiment is configured to bias the lever 35, but the spring 53 is connected to the upper surface of the torch support 19 as shown in FIG. The one end of the coat portion 31 of the power transmission cable 29 is urged upward by the spring 53 in FIG. 4 so that the wire 33 and the coat portion 31 are always urged in the direction away from each other. Or any other method.

In the above embodiment, the power transmission cable 29 is used as the power transmission device.
Other mechanical power transmission devices such as a link mechanism and an interlocking member may be used.

In this embodiment, a plasma processing machine has been described as an example of a thermal cutting apparatus, but a laser processing machine or other thermal cutting apparatus may be used.

[0057]

As will be understood from the above description of the embodiment of the invention, according to the first aspect of the present invention, the torch support portion is urged so as to always press against the torch holder. Since the torch is detachable, even if the torch collides with an obstacle, the torch can be easily protected against the urging force, so that the torch can be protected. In addition, since the movement of the torch support that separates from the torch holder due to the collision of the torch can be reliably transmitted by the power transmission device, the detected member is moved, and the operation of the detected member is detected by the collision detector to thereby prevent the torch from moving. Can detect collisions.

Therefore, since the collision detector is not provided around the torch, the periphery of the torch can be simplified, so that the collision detector can be easily adjusted. It is possible to avoid a situation in which the control device is intruded through the container. Accordingly, an inexpensive general-purpose detector can be used as a collision detector.

According to the second aspect of the present invention, the effect is the same as that of the first aspect, and the torch supporting portion is normally urged to be in pressure contact with the torch holder, but can be freely moved in and out. Even if the vehicle collides with an obstacle, the torch can be easily tilted against the biasing force, so that the torch can be protected. Moreover,
The movement of the torch support part, which separates from the torch holder due to the collision of the torch, can be reliably transmitted by the power transmission device, so that the detected member is moved, and the operation of the detected member is detected by the collision detector to detect the collision of the torch. Can be detected.

Therefore, since the collision detector is not provided around the torch, the periphery of the torch can be simplified, so that the adjustment of the collision detector can be easily performed. It is possible to avoid a situation in which the control device is intruded through the container. Accordingly, an inexpensive general-purpose detector can be used as a collision detector.

According to the third aspect of the present invention, since the coat portion and the power transmission wire are urged in a direction in which they are relatively separated from each other, the torch support portion can be urged so as to be constantly pressed against the torch holder. The torch's collision force can be absorbed and the torch can be protected. In addition, since the torch support portion is tilted and separated from the torch holder due to the collision of the torch, the power transmission wire is pulled against the biasing direction and the lever is reliably swung, and the collision detector can detect the collision of the torch.

According to the fourth aspect of the present invention, since the plurality of power transmission devices are provided at substantially symmetrical positions around the torch, even if the torch support is slightly separated from the torch holder due to the collision of the torch, The movement of the torch support can be transmitted to the lever by at least one power transmission device, and the collision of the torch can be detected sensitively.

[Brief description of the drawings]

FIG. 1, showing an embodiment of the present invention, is a front view of a torch collision detection device in a plasma processing machine.

FIG. 2 is a plan view taken along line II-II in FIG.

FIG. 3 is an explanatory diagram of a state when the torch collides with an obstacle according to the embodiment of the present invention.

FIG. 4 shows another embodiment of the present invention, and is a front view of a torch collision detection device in a plasma processing machine.

FIG. 5 is a side view of a torch collision detection device in a conventional plasma processing machine.

FIG. 6 is an enlarged sectional view showing a mounting state of a conventional collision detector.

FIG. 7 is an explanatory diagram of a state when a torch collides with an obstacle in a conventional example.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 plasma processing machine 3 torch (plasma torch) 5 torch holder 7 torch head (machine main body) 11 torch collision detection device 15 holder unit 17 torch insertion hole 19 torch support unit 23 torch collision detection unit 27 collision detector (limit switch LS) 29 Power transmission cable (power transmission device) 31 Coat part 33 Wire (power transmission wire) 35 Lever (detected member) 49 Wire operating member 51, 53 Spring (biasing means)

Claims (4)

[Claims] 1. A torch is inserted into a torch insertion hole of a torch holder provided in a machine main body, and a torch support portion provided on an outer periphery of the torch is urged to be constantly pressed against an upper surface of the torch holder. The movement of the torch support portion when it collides with the torch and tilts is transmitted by a power transmission device to a movable detection target member provided on the machine body, and the operation of the detection target member is detected by a collision detector. A thermal cutting method, wherein the method detects a collision. 2. A torch holder having a torch insertion hole for inserting a torch to be thermally cut into a workpiece is provided on a machine body. A torch support is provided on an outer periphery of the torch, and the torch support is provided on an upper surface of the torch holder. A torch collision detection unit having a movable detection member and a collision detector for detecting the operation of the detection member is provided on the machine body. A power transmission device for transmitting the movement of the torch supporter to the member to be detected. 3. The power transmission device comprises: a tube-shaped coating portion; and a power transmission wire inserted through the coating portion, and the detected member comprises a swingable lever. One end of the power transmission wire is attached to the torch support portion, the other end of the coating portion is attached to the torch collision detection portion, one end of the power transmission wire is attached to the torch holder, and the other end of the power transmission wire is attached to the lever, 3. The power transmission wire and the coating portion are biased in a direction in which the power transmission wire and the coating portion are relatively separated from each other by a biasing means so that a torch support portion of the torch is constantly pressed against the torch holder. The thermal cutting apparatus according to the above. 4. A thermal cutting apparatus according to claim 2, wherein a plurality of said power transmission devices are arranged at substantially symmetrical positions around a torch.