JPH01170589A - Laser beam machine - Google Patents

Abstract

PURPOSE:To obtain a safe laser beam machine which can be easily operated by providing a means to store a gap holding command, a means to decide whether or not a moving command is rapid traverse and a gate means to check passing of the gap holding command during the rapid traverse mode. CONSTITUTION:The gap holding command storage means 17 stores a gap holding command signal to command to hold an inputted gap L between a nozzle end 1a of a machining head and the surface of material 7 to be machined at a set value and continues to output said signal. On the other hand, the rapid traverse decision means 18 discriminates whether the moving command to move the machining head relatively to the material to be machined is the rapid traverse mode or the ordinary mode. The gate means 19 is controlled by an output signal of said rapid traverse decision means 18 and checks passing of the gap holding command signal outputted by said gap holding command storage means 17 during a period of time of the rapid traverse mode of said mobile command. By this method, since a function to hold said gap at the set value is stopped automatically, the safe laser beam machine which is easily operated can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a laser processing machine having a control function to maintain the laser focal point tTh at an optimum amount on the surface of a workpiece.

[Conventional technology]

When processing a workpiece with a laser, JP-A-Sho is a laser processing machine that maintains the laser focusing position tF at the optimum position Eζ on the surface of the workpiece, regardless of the surface condition of the workpiece. One disclosed in Japanese Patent No. 59-223189 is known.

FIG. 3 is a block diagram showing a processing head and its control circuit of a conventional laser processing machine disclosed in the above-mentioned Japanese Patent Laid-Open No. 59-223188. In fig.

(1) is the processing head, (1 &) is the nozzle end which is the laser emission port, (11)) d is the assist gas inlet, (
2) is a light guiding part that guides the laser beam (D) to the processing head fil, (3) is a condensing lens, and (4) is a processing head (1).
A drive mechanism that moves in the direction of arrow A, driven by a servo motor (
5) and an adjustment screw (6). (7)
α2 is a flat workpiece placed on the processing table (7), and α2 is a distance sensor that measures the gap between the workpiece (7) and the nozzle end (1a) of the processing head (1). ,
<131 is a comparison means, and I is a servo motor driving means for controlling and driving the servo motor (4).

Next, the operation will be explained. Laser light (DIVi) is condensed and irradiated onto the workpiece (7) by a condensing lens (3) provided on the processing head (1).The condensing position F of this laser
is, for example, the surface of the workpiece (7) during laser processing.

For this reason, it is important to maintain a constant position Cζ with respect to the workpiece (7) in order to secure machining costs.

The distance sensor side measures the gap between the nozzle end (1a) of the processing head (1) and the workpiece (7) in place of the laser focusing position F on the workpiece (7), comparison means fi
3 compares the output signal ■ from the distance sensor side mentioned above and the signal v□ input from the terminal (13), and outputs the difference signal Δ■
The servo motor drive means I outputs the above comparison means q3.
The servo motor (5) is controlled and driven so that the output signal ΔV becomes zero, and the servo motor (5) and adjustment screw (6)
The drive mechanism (4) consisting of fζ and the processing head (1)
By moving in the direction of arrow A.

Automatic control is performed so that the gap becomes the set value LQ. Therefore, instead of moving the processing table (8) in the direction of arrow B, for example, the workpiece (7) having smooth unevenness is
) moves, the gap is always maintained at the set value LQ.

However, when the machining head (1) is moved relatively quickly for 2-positioning, etc., in other words, the machining table (
8) in the direction of arrow B, there is a case where Eζ passes over a part of the workpiece (7) that has already been cut and has a hole.In this case, the gap is set to a constant value LQ. Due to the control function Cζ maintained at Cζ, there is a risk that the processing head (1) descends in the downward direction Cζ of the arrow A and collides with the workpiece (7) at the hole portion Eζ. In order to prevent this danger, a switch means (not shown) is generally provided to stop the operation of the control function, so that the control function does not operate during relative rapid movement of the processing head (1).

[Problem that the invention seeks to solve]

Nozzle end (1a) of processing head (1) and workpiece (7)
In a conventional rapping machine, in which a control function for maintaining a constant gap lζ is manually turned off by a switch means, when the machining head is rapidly moved relative to the workpiece, the gap The automatic control function that maintains the temperature at the set value LQ must be stopped by turning off the switch means.

There is a problem in that if this cutting action is forgotten, there is a risk of damaging the processing head.

This invention was made to solve the above-mentioned problems.
ζThe objective is to obtain a safe laser processing machine that can automatically stop the automatic control function that maintains the gap between the nozzle end of the processing head and the workpiece at the set value during the period of rapid forwarding. shall be.

[Means for solving problems]

In the laser processing machine according to the present invention, upon input of a gap maintenance command and a movement command, the processing head moves relatively over the surface of the workpiece while maintaining the gap between the nozzle tip and the workpiece at a set value. and a gap holding command storage means for storing the gap holding command, and a fast forward determination means for determining whether or not the movement command is in a fast forward mode.

Gate means is controlled by the output signal of the fast-forward determining means and does not allow an output signal instructing gap maintenance from the gap-maintaining command storage means to pass during a period in which the movement command is in the fast-forward mode.

[Effect]

The gap holding command storage means in this invention stores the input gap holding command signal instructing to maintain the gap between the nozzle end of the processing head and the surface of the workpiece at a set value,
This signal continues to be output, but on the other hand, the rapid traverse determination means determines whether the movement command for moving the machining head relative to the workpiece is the rapid traverse mode or the normal mode, and the gate means It is controlled by the output signal of the gap determining means to prevent passage of the gap holding command signal output from the gap holding command storage means during the period when the movement command is in the fast forward mode.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. In the drawings, parts denoted by the same reference numerals as those of the conventional example are the same as those of the conventional example or correspond to the conventional example.

FIG. 1 is a block diagram showing a processing head portion, a processing table, and a control circuit thereof of a laser processing machine according to this embodiment. In the figure, (9) is a servo motor that constitutes a drive mechanism that moves the processing table (8) in the direction of arrow B, (IQ is a servo motor drive means that controls and drives this servo motor (9). The processing head mentioned above In order to enable the processing head (1) to move relatively arbitrarily on the XY plane of the processing table (8), a set of drive mechanisms and servos are provided to control and drive the processing head (1) in a direction perpendicular to the plane of the paper. Although there is a motor drive means, its description is omitted. α9 is a gap control means that controls fζ to maintain the gap between the nozzle end (1a) of the processing head (1) and the workpiece at a set value. ), comparison means αj and servo motor drive means (14a
). This gap control means υ is a distance sensor 1121 that measures the gap. A drive mechanism (4) comprising a servo motor (5) and an adjustment screw (6) constitutes a negative feedback control system that automatically controls the gap to maintain it at a set value. (LD is the gap control means αυ
gap holding command storage means for storing a gap holding command signal for all automatic control commands to hold the set value Iζ of the gap according to the above, and outputting a continuous signal; fi seconds is a fast forward judgment means;
The processing head (1) input from terminal α9 is connected to the workpiece (
7) In other words, the servo motor drive means α1 analyzes the movement command to move relative to the processing table (8), and the rapid traverse determination means determines whether or not the analyzed movement code is in the rapid traverse mode. It determines and outputs a signal when it is in fast forward mode. The gate means controlled by the output signal of α9 company's fast-forward discrimination means (II) inputs a control signal indicating that A2 is normally in a conductive state Eζ, and that the fast-forward discrimination means a and fast-forward! This is to prevent the gap holding command signal for the gap B outputted from the gap holding storage means αn from being input to the gap control means (11) of the processing head (1) when the cine conduction occurs. .

FIG. 2 is a flow diagram showing the operation of the control circuit, and the operation of the control circuit will be explained below with reference to this figure. First, a gap maintenance command signal is sent to the terminal ( 1b) (Step 101L) The gap maintenance command storage means αη stores the gap maintenance command signal and continuously outputs this signal (step 102), the output of this gap maintenance command signal is Command storage means α
This continues until a reset signal is input to D. - The servo motor driving means section decodes the movement command signal inputted from the million terminal α9, which instructs the relative movement of the processing head (1) and the processing table (8), and the fast forward 9 judgment means a♂ It is determined whether the movement is due to the fast forward mode tζ or the 2 normal mode (step 103).

The gate means fi9, which is controlled by the output signal of the fast-forward determination means U, operates when the output signal of the fast-forward determination means U is OFF;
That is, in the case of the normal mode, it becomes conductive (ON) (step 104), and the output signal of the gap maintenance command storage device (LD) is inputted to the control device α and ζ via the gate device σ9, and the gap is set to the set value. Automatic control is performed to maintain lζ, but when the output signal of the fast-forward determining means aS is ON, that is, in the fast-forward mode, Eζ becomes non-conductive (OF
F) Then (step 1θ5), the output signal of the gap holding command storage means is prevented from conducting by the gate means a9, so that the gap I4-set value by the gap control means (11) K is The automatic control maintained at 9 is stopped, and 1 is moved, for example, in the upward direction of arrow A for evacuation, in response to a movement command input separately. Namely.

Even if the automatic control mode is selected in which the gap is maintained at the set value based on the gap maintenance command, the set value lζ of the gap of the gap control means αD is maintained during the period when the movement command is in the fast forward mode. The control function is automatically stopped fζ.

Although the above embodiment has been described using a two-dimensional laser processing machine, a three-dimensional laser processing machine that processes three-dimensional shapes can also produce similar effects.

〔Effect of the invention〕

As described above, according to the present invention, the gate means controlled by the output of the fast-forward determination means for determining whether or not the movement command is in the fast-forward mode is activated during the period in which the movement command is in the fast-forward mode. The function that maintains the gap between the nozzle end of the processing head and the workpiece at the set value is automatically stopped by preventing passage of the gap hold command that maintains the gap between the nozzle end of the processing head and the workpiece at the set value, making the operation easy. This has the effect of providing a safe laser processing machine.

[Brief explanation of the drawing]

FIG. 1 is a block diagram schematically showing the relationship between a processing head and a processing table of a laser processing machine according to an embodiment of the present invention, and their control circuits. FIG. 2 is a flow diagram showing the operation of the control circuit shown in FIG. 1, and FIG. 3 is a block diagram schematically showing the relationship between the processing head of a conventional laser processing machine and its control circuit. In Figure 1ζ, (1) is the processing head, (Ia) is the nozzle end of the processing head, (3) is the condenser lens, (4) is the drive mechanism, (5) and (9) are the servo motors, and (7) is the workpiece,
(8) is processing tape A', (IQ), (14a) is servo-motor drive means, U is gap control means, housing is distance sensor, ti3 is comparison means, αη is gap holding command storage means, αg is fast Feedback determination means. α3 is gate means. In the two figures, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] The processing head is configured to move relatively over the surface of the workpiece while maintaining the gap between the nozzle tip and the workpiece at a set value by inputting a gap maintenance command and a movement command. A gap maintenance command storage means for storing a gap maintenance command; a fast-forward determination means for determining whether or not the movement command is in the fast-forward mode; controlled by the output signal of the fast-forward determination means, during the period when the movement command is in the fast-forward mode A laser processing machine characterized by comprising a gate means that does not allow an output signal instructing gap maintenance from a gap maintenance command storage means to pass through.