JPH11320101A - Work detecting method and equipment in plate processing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce cost without causing NC malfunction due to disturbance such as noise and without necessity of correction each time even when consumable parts in a torch are replaced with different types. SOLUTION: Above a work W, a processing head 13 equipped with a torch 15 is provided in a vertically movable way, and the torch 15 is integrally installed to a torch holder 39 to form a flange portion 39A. Further, the torch holder 39 is installed in a vertically movable way to a torch base 37 to form the processing head 13, and also brought into contact with the torch base 37 via a spring 47, and is provided with multiple detecting sensors 49 which detect that the torch holder 39 rises from the torch base 37. This does not cause NC malfunction, does not require correction after the torch is replaced, and can reduce cost.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for detecting a work in a plate processing machine such as a plasma processing machine and a laser processing machine.

[0002]

2. Description of the Related Art Conventionally, as a work surface detecting device provided in a plasma processing machine as a plate material processing machine, for example, a work surface detecting device as shown in FIG. 7, FIG. 8 or FIG. 9 is known.

That is, in the work surface detecting apparatus 101 shown in FIG. 7, an electric contact 105 is provided at the tip of the torch 103. When the tip of the torch 103 comes into contact with the work W, a small current flows, and the lowering of the torch 103 stops. Then rise. Then, when the current is separated from the work W, the current is turned off, and that position is set as the work surface.

A work surface detecting device 10 shown in FIG.
Reference numeral 1 denotes an ultrasonic sensor 107 provided at a predetermined interval (offset amount a) from the center of the torch 103, and the ultrasonic sensor 107 is used to view the surface position of the work W.

That is, the distance h is detected in FIG.
Torch 1 with work W at S = h-ho (ho: set value)
The distance from the optical axis 03 is detected.

Further, a work surface detecting device 10 shown in FIG.
Reference numeral 1 denotes an air cylinder 109 provided at a predetermined interval (offset amount a) from the center of the torch 103, a sensor 113 provided at the tip of a piston rod 111 of the air cylinder 109, and a work W The surface of the work W is detected by the contact.

Furthermore, a detecting device known from Japanese Utility Model Laid-Open No. 5-68468 discloses an annular engaging concave portion provided on a flange portion of a torch holder constituting a part of a plasma processing head. An engaging projection is provided on the periphery of a supporting ring provided on an elevating plate of the elevating body constituting the head, the engaging projection engaging with the engaging recess under linear contact.

[0008]

By the way, in the above-described conventional work surface detecting apparatus in the plasma processing machine,
The work surface detection device 101 shown in FIG.
Only the torch having an electrical connection at the tip of the 03 can be used, and the noise at the time of generation of strong plasma from the signal cable enters the NC device to cause malfunction.

The work surface detecting device 101 shown in FIGS. 8 and 9 comprises sensors 107 and 113 and a torch 10.
3, there is an interval of the offset amount a, and the actual surface of the tip of the torch 103 is not detected. In addition, a wasteful movement and a stroke such as moving the offset at the time of detection by software processing, returning the offset by the offset after detecting the processing position, and starting the processing are required. Furthermore, if the length of the tip of the torch changes when consumables (electrodes, nozzles, shields, etc.) are replaced with another type, it is necessary to change the sensor position and the correction value of the tip of the torch each time the torch is replaced. Still further, the ultrasonic sensor 10
7 and the laser displacement meter are very expensive.

The detector disclosed in Japanese Utility Model Laid-Open No. 5-68468 detects the inclination of the torch when the machining head and the work interfere with each other, and cannot detect the surface of the work.

SUMMARY OF THE INVENTION An object of the present invention is to prevent a malfunction of an NC due to disturbances such as noises, and to replace a consumable in a torch with a different kind, so that it is not necessary to perform correction each time, thereby reducing the cost of processing a plate material. An object of the present invention is to provide a method and a device for detecting a work in a machine.

[0012]

According to a first aspect of the present invention, there is provided a method for detecting a work in a plate processing machine according to the present invention, wherein a work head having a torch is provided at a position above a work so as to be able to move up and down. In plate processing machines,
(A) a processing head fast-forwarding step in which the processing head is fast-forwarded and lowered from an origin position, which is an ascending limit, to a position in consideration of the thickness of a work; (C) The processing head is lowered in the processing head step feeding step, the tip of the torch provided on the processing head comes into contact with the surface of the work, and the processing head is further lowered. And the contact between the torch holder and the torch base is released against the urging force of the machine, the torch is pushed upward, and the signal of the detection sensor provided on the torch enters to detect the surface of the work. ,
(D) when the signal of the detection sensor is received in the work surface detection step, the lowering of the processing head is stopped, and the processing head is raised in reverse and the step is raised. (E) The detection is performed simultaneously with the processing head step raising step. A signal from the sensor is cut off, and the position at this time is calculated by a distance detecting means provided in a vertical movement driving device of the processing head, and a processing surface reference setting step is set as a work surface reference as a work surface position; After the surface reference setting process is completed, the work head is rapidly moved up to a height set by a program, and then the work operation is started before the work operation is performed. (G) The detection sensor detects the torch and the work by the detection sensor during the work work process. And a work collision detection step of detecting a collision when some force acts on the torch due to interference between the two.

According to a second aspect of the present invention, there is provided a plate material processing machine according to the present invention, wherein a work head having a torch is provided at a position above a work so as to be able to move up and down. The torch holder is formed integrally with the torch holder, and the torch holder is mounted on a torch base provided on a slider constituting the processing head so as to be vertically movable. A plurality of detection sensors are provided on the flange portion of the torch holder to detect that the torch holder has floated and separated from the torch base and to detect that the torch holder has separated from the torch base when a collision occurs. It is characterized by becoming.

Therefore, the torch is fixed to the torch holder, and the torch holder is mounted on the torch base via the bobbin by using the method and the apparatus for detecting a work in the plate processing machine according to the first and second aspects of the present invention. The torch holder is provided with a detection sensor that detects the surface of the work and detects that the work has collided.When the tip of the torch provided on the torch holder comes into contact with the work, the torch holder floats and the detection sensor detects the collision. To detect the position of the upper surface of the work, and also detects that the work has collided with the work.

Thus, the inexpensive detection sensor does not cause the NC operation due to noise. Even if the length of the tip of the torch changes, it is detected at the tip of the torch, so no correction is required, and there is no offset from the sensor. There is no need for unnecessary movement.

According to a third aspect of the present invention, there is provided a work detecting apparatus for a plate material processing machine according to the present invention, wherein the flange of the torch holder serves as a guide for vertical movement with respect to the torch base. A plurality of guide members are provided to hang down from the portion, and a seat plate with which the guide members abut is provided on the torch base side.

Therefore, by using the work detecting device in the plate processing machine according to the third aspect of the present invention, a plurality of seat plates provided on the torch base serve as guides when the torch holder moves up and down with respect to the torch base. The provided guide member was abutted. Thus, when the tip of the torch provided on the torch holder collides with the work, the torch holder tilts, the detection sensor operates and the machine stops, so that one detection sensor detects the work surface and the collision. Can play a role.

According to a fourth aspect of the present invention, there is provided a work detecting apparatus for a sheet material processing machine according to the present invention, wherein the detection sensor comprises a proximity switch. Is what you do.

Therefore, by using a proximity switch as the detection sensor, it is possible to detect with high accuracy and to be inexpensive.

[0020]

Embodiments of the present invention will be described below in detail with reference to the drawings.

Referring to FIGS. 5 and 6, first, for ease of understanding, an overall configuration of, for example, a plasma processing machine as a plate processing machine will be schematically described.

The plasma processing machine 1 comprises a torch frame 9 supported on one side by a guide 5 provided on a support column 3 and the other side on a rail member 7. The torch frame 9 is arranged in the X-axis direction (in FIG. 5). It is provided movably in a direction perpendicular to the drawing, that is, in the left-right direction in FIG.

The torch frame 9 is provided with a torch carriage 11 which is movable in the Y-axis direction (the left-right direction in FIG. 5 and the up-down direction in FIG. 6). 5, vertical direction, FIG.
(A direction orthogonal to the drawing in FIG. 1) is mounted. Further, a torch 15 movable in the Z-axis direction is mounted on the processing head 13.

A work table 17 is provided below the processing head 13, and a work W is fixed on the work table 17 by appropriate means.

With the above structure, the work W fixed on the work table 17 is plasma-processed by the torch 15 by the torch frame 9 moving in the X-axis direction and the torch carriage 11 moving in the Y-axis direction. Things.

Reference numeral 19 denotes an NC unit, and reference numeral 2 denotes
1 is a dust collector.

Next, the torch 15 provided on the processing head 13 which is a main part of the present invention will be described in more detail.

Referring to FIGS. 1 and 2, the torch carriage 11 is provided with a processing head 13 movably in a Z-axis direction (a vertical direction in FIG. 1 and a direction perpendicular to the drawing in FIG. 2). . More specifically, a drive pulley 27 is mounted on an output shaft 25 of a Z-axis servomotor with encoder 23 as a distance detecting means provided in the torch carriage 11, while a driven pulley 31 is mounted on a Z-axis ball screw 29, A belt 33 is wound around the driven pulley 31 and the driving pulley 27. Further, a Z-axis slider 35 constituting the machining head 13 is mounted via a nut member (not shown) screwed to the Z-axis ball screw 29.

With the above configuration, when the Z-axis servomotor with encoder 23 is driven, the driving pulley 27 rotates and the rotation is transmitted to the driven pulley 31 via the belt 33. Then, the Z-axis ball screw 29 on which the driven pulley 31 is mounted is rotated, and the Z-axis slider 35 is position-detected by the encoder of the Z-axis servomotor 23 with an encoder via the nut member, and can be moved in the Z-axis direction.

A torch base 37 projects from the lower end of the Z-axis slider 35, and a torch holder 39 having the torch 15 mounted thereon is inserted into the torch base 37, and a back surface of a flange 39A formed on the torch holder 39 is formed. The surface of the torch base 37 can be in contact with or separated therefrom. The plurality of knob screws 41 provided on the torch holder 39 are for fixing the inserted torch 15 to the torch holder 39.

A spring receiving plate 45 is provided at a lower end of a plurality of bolts 43 hanging down from a flange portion 39A formed by the torch holder 39.
A coil spring, for example, is mounted as an elastic machine 47 between the torch base 37 and the torch base 37.

With the above-described configuration, the flange portion 39A formed on the torch holder 39 is always provided by the elasticity of the elastic machine 47.
Is in contact with the upper surface of the torch base 37 and the torch 15
When abuts against the workpiece W, the flange portion 39 </ b> A floats from the upper surface of the torch base 37 against the elasticity of the elastic machine 47.

As an example of the detection sensor 49, for example, proximity switches are provided at a plurality of locations (two locations in this embodiment) on the flange portion 39A formed on the torch holder 39. This detection sensor 49 is used for the torch 15 during the cutting process.
The operation of the collision sensor is switched by software processing, and if any force acts on the torch 15 during machining, a signal from the detection sensor 49 is input to stop the machine.

The torch holder 3 having the torch 15
As shown in detail in FIG. 3, a plurality of guide pins 53, which are guide members, are vertically suspended from a flange portion 39A of the torch holder 39 as a guide 51 when the 9 moves up and down or tilts. Is in contact with a curved seat 55 which is a seat plate provided on the torch base 37.

With the above configuration, when the torch holder 39 provided with the torch 15 moves up and down or tilts, the guide pin 5
3 makes it possible to move up and down smoothly, and to smoothly tilt even if a load is applied to the torch 15 from any direction.

With the above-described configuration, the operation is as follows. Referring to FIG. 4, first, in order to detect the surface of the work W, the torch 15 is located at the origin position which is the ascending limit. A coordinate system is set as a reference. next,
In rapid traverse, for example, taking into account the thickness of the workpiece W (thickness +
α), and then step down until the tip of the torch 15 hits the work W by step feed.

When the tip of the torch 15 hits the work W, the torch 15 is pushed upward, the guide pin 53 provided on the torch holder 39 floats from the curved seat 55, and the detection sensor 49 is turned on when it is separated from the surface of the torch base 37. Becomes
Then, the descent of the torch 15 is stopped, and the torch 15 is turned upside down to step up.

When stepping up, the torch 15 is
7 returns to the original position by the resilience of the detection sensor 4 again.
7 is OFF. The position (signal) at this time is calculated by the encoder, and is used as a reference for the descending surface as the surface position of the work W. Then, from this point, the torch 15 rapidly moves up to the piercing height set by the program and continues to the plasma ignition operation.

When any force acts on the torch 15 during machining, the detection sensor 49 switches the operation of the collision sensor of the torch 15 to the operation of the torch 15 on the software of the NC device during cutting. When the torch holder 39 provided with the collides with the work W, the torch 15 is inclined against the resilience of the bullet 47. At this time, the detection sensor 49 provided on the torch holder 39 is separated from the torch base 37 and turned on, and the machine stops.

Since the detection sensor 49 employs a proximity switch, it has high accuracy, is very inexpensive as compared with an ultrasonic sensor or a laser displacement meter, and one unit serves two roles. In addition, since the signal is not a signal due to energization like a touch sensor, it does not cause NC malfunction due to noise. Even if the tip of the torch 15 changes length, correction is performed because the surface of the work W is detected at the tip of the torch 15. Is unnecessary, and there is no offset from the sensor.

The present invention is not limited to the above-described embodiment, but can be embodied in other forms by making appropriate changes. For example, although the detection sensor 49 is a proximity switch, the present invention is not limited to this type. The detection sensor 49 is provided directly on the torch holder 39, but the sensor may be detected via another actuator.

[0042]

As will be understood from the above description of the embodiments, according to the present invention according to claims 1 and 2,
The torch is fixed to the torch holder, and the torch holder rides on the torch base via a bullet. The torch holder is provided with a detection sensor that detects the surface of the work and detects that the work has collided.When the tip of the torch provided on the torch holder comes into contact with the work, the torch holder floats and the detection sensor detects the collision. To detect the position of the upper surface of the work and the collision with the work.

Thus, an inexpensive detection sensor does not cause NC operation due to noise. Even if the length of the tip of the torch changes, it is detected at the tip of the torch, so no correction is required, and there is no offset from the sensor. There is no need for unnecessary movement.

According to the third aspect of the present invention, a guide member provided on the torch holder is brought into contact with a plurality of seat plates provided on the torch base as guides for tilting the torch holder up and down with respect to the torch base. Thus, when the tip of the torch provided on the torch holder collides with the work, the torch holder tilts, the detection sensor operates and the machine stops, so that one detection sensor detects the work surface and the collision. Can play a role.

According to the fourth aspect of the present invention, since the detection sensor is a proximity switch, the detection can be performed with high precision, the cost is low, and the operation of two roles can be performed by one.

[Brief description of the drawings]

FIG. 1 is an explanatory sectional view of a processing head provided with a torch, showing a main part of the present invention.

FIG. 2 is an explanatory plan view of FIG. 1;

FIG. 3 is an enlarged cross-sectional view taken along the arrow III in FIG.

FIG. 4 is an operation explanatory view.

FIG. 5 shows an embodiment of the present invention and is a front view of a plasma processing machine.

FIG. 6 is a plan view of FIG.

FIG. 7 shows a conventional example and is a front view of a work surface detecting device.

FIG. 8 is a front view of a work surface detecting device showing another example of the conventional example.

FIG. 9 is a front view of a work surface detection device showing another example of a conventional example.

[Explanation of symbols]

 Reference Signs List 1 plasma processing machine (plate processing machine) 13 processing head 5 torch 23 Z-axis servo motor with encoder 29 Z-axis ball screw 35 Z-axis slider 37 torch base 39 torch holder 39A flange portion 47 bullet unit 49 detection sensor 51 guide 53 guide pin (guide) 55) Curved seat (seat plate)

Claims (4)

[Claims] 1. A plate material processing machine comprising a processing head provided with a torch at a position above a work so as to be able to ascend and descend. (A) The work head is considered in consideration of the thickness of the work from an origin position, which is an ascending limit. A machining head fast-forwarding step of rapidly moving down to a position; (B) a machining head step-feeding step of lowering the machining head by step-feeding after completion of the machining head rapid-feeding step; and (C) a machining head in the machining head step-feeding step. When the tip of the torch provided on the processing head comes into contact with the surface of the workpiece and continues to lower the processing head, the contact between the torch holder and the torch base separates against the urging force of the machine. A workpiece surface detecting step of detecting a workpiece surface by receiving a signal from a detection sensor provided on a torch by being pushed upward, (D) the workpiece table When the signal of the detection sensor is input in the detection step, the lowering of the processing head is stopped, and the processing head is raised in reverse and the step is raised. (E) The signal of the detection sensor is cut off simultaneously with the processing head step raising step. The position at this time is calculated by a distance detecting means provided in the drive device for vertically moving the processing head, and a processing surface reference setting step is set as a work surface reference as a work surface position. (F) After the processing surface reference setting step is completed (G) a workpiece machining step in which the machining head is rapidly advanced to a height set in a program and then enters a machining operation; and (G) interference occurs between the torch and the workpiece by the detection sensor during the workpiece machining step. A work collision detection step of detecting a collision when some force acts on the torch. . 2. A plate material processing machine comprising a processing head provided with a torch at a position above a work so as to be able to move up and down, wherein the torch is provided integrally with a torch holder having a flange portion formed at an upper end, and the torch holder is used for the processing. The torch base is mounted on the torch base provided on the slider constituting the head so as to be able to move up and down, and the flange formed on the torch holder is constantly urged to contact the torch base via a bobbin, so that the torch holder floats from the torch base. A workpiece detecting device for a plate material processing machine, comprising a plurality of detection sensors provided on a flange portion of the torch holder for detecting separation and detecting that the torch holder is separated from a torch base when a collision occurs. 3. A plurality of guide members are provided hanging down from a flange portion of the torch holder as a guide for vertical movement with respect to the torch base, and a seat plate with which the guide members abut is provided on the torch base side. The workpiece detecting device in a plate processing machine according to claim 2, wherein: 4. The work detecting apparatus according to claim 2, wherein the detection sensor is constituted by a proximity switch.