JPH04187390A - Laser beam machine - Google Patents

Abstract

PURPOSE:To automatically maintain the intensity of a laser beam constant regardless of the secular deterioration of a light source, the change of environment, etc., by maintaining a control signal given to a laser beam oscillating means by a laser beam output control means at a value right before off during off of the laser beam oscillating means. CONSTITUTION:In marking of a laser beam marker, for instance, a detection value and a set value of laser beam power are compared with each other and a laser beam generation part 1 is controlled to maintain the laser beam power constant via a controller 8 and the laser beam generation part 1 is turned on and off and marking is performed while following the work 5 surface by a single stroke writing system by the laser beam LB. At that time, when this laser beam generation part 1 is turned off, in order to prevent variation of the laser beam power when the laser beam generation part 1 is turned on by laser beam power detection output disappearance to the controller 8, when the laser beam generation part 1 is turned off, the laser beam power detection value right before it is stored and changeover is given to the controller 8 instead of the actual laser beam detection output and variation of the control output of the controller 8 is prevented.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a laser processing device such as a laser marker.

[Conventional technology]

The laser power of the laser marker is determined by the deterioration of the driving lamp light source over time and by variations in the lamp when it is replaced. Dirt on the optical system, changes in lamp cooling water pressure and temperature. Since it fluctuates due to changes in ambient temperature, etc., conventionally the laser power was measured and, for narrow marking conditions, the lamp current was manually adjusted to a predetermined value using a power meter while marking was stopped.

[Problem to be solved by the invention]

However, the method of adjusting the laser power as described above has drawbacks such as being labor-intensive and being unable to cope with changes in lamp cooling water pressure, temperature, and ambient temperature. Therefore, the present invention has been made to solve the above problems, and by providing a laser processing device that automatically controls laser power to a preset laser power value during laser processing, marking quality can be kept constant. At the same time, the purpose is to save labor.

[Means to solve the problem]

In order to solve the above problem, the laser processing apparatus of claim 1) includes an r laser reflecting mirror (2, etc.), a laser output mirror (3, etc.).
) and a laser generating unit (such as 1) that generates a laser beam, and a power detecting unit (detector 6) that extracts a part of the laser beam from the laser oscillating unit and converts it into a laser power detection signal. ), and the laser power detection signal (6a, therefore, the cuff 8, etc.) is compared with the setting value (9a, etc.) (of the setting device 9, etc.), and the laser oscillation means is controlled so that the two match. a laser output control means (adjuster 8, laser power control device 10, etc.) that turns on and off the first stage of the laser oscillation means (via an ON-OFF signal 21 etc.) to perform a predetermined work. The processing apparatus according to claim 2, wherein while the laser oscillation means is turned off, the control signal given by the laser output control means to the laser oscillation means is maintained at a value immediately before the turning off. The laser processing apparatus according to claim 1) further comprises a detection signal holding means for holding the laser power detection signal immediately before the laser power oscillation means is turned off and supplying the same to the laser output control means. In the laser processing apparatus according to claim 3), in the laser processing apparatus according to claim 2), r the detection signal holding means transfers the laser power detection signal from the power detection means to the laser oscillation means. a storage unit (such as a storage unit 12) that stores and outputs the data immediately before turning off (based on the data update command 22, etc.), and a laser power detection signal to be given to the laser output control unit to turn the laser oscillation unit on and off. Accordingly, the power detection means and the storage means are respectively equipped with switching means (changeover switch 11, etc.).

[For use]

The laser generator is controlled by comparing the detected value of the laser power with the set value via the regulator, keeping the laser power constant, and turning on the laser generator while tracing the work surface with the laser beam in a single stroke. Marking is performed when the laser generator is off, but in order to prevent the laser power from changing when the laser generator is on due to loss of laser power detection output to the regulator when the laser generator is off, the The immediately preceding laser power detection value is stored and applied to the regulator instead of the actual laser power detection output, thereby preventing fluctuations (disturbances) in the control output of the regulator.

【Example】

FIG. 1 is a system configuration diagram of a laser marker as an embodiment of the present invention, and FIG. 2 shows an example of marking based on the apparatus shown in FIG. In FIG. 1, 1 is a laser generating section, 2 is a reflecting mirror, and 3 is an output mirror, and a laser oscillation means constituted by these three generates a laser beam. Note that the laser generating section 1 starts and stops the laser output in accordance with the applied ON-OFF signal 21. 4 is a positioning mirror, which connects the laser generator 1 to the output mirror 3.
The laser beam LB outputted through is reflected and applied to the workpiece 5 to be marked, and the beam L hitting the workpiece 5 is
It is a mirror that positions B in the coordinate axes X and Y directions, and its attitude (reflection angle) is controlled by a galvanometer (not shown) for positioning this X and Y position. 6 is during laser marking in the solid line portion described later in FIG. 2, that is, during laser oscillation. This is a detector that extracts a part of the laser beam from the reflecting mirror 2 and detects its power intensity.The output 6a is further amplified by an amplifier 7, and this amplified product output cuff a is connected to a selector switch 11 on the one hand. The signal is inputted to the regulator 8 via the a contact point, and is applied to the storage section 12 on the other hand. The regulator 8 outputs the detection output 6a, and thus increases the output cuff a and the set value 9 of the setter 9.
a is compared, and an adjustment signal 8a is applied to the laser power control device 10 so that the two match, and the laser power output from the laser generating section 1 is controlled to be constant via the laser power control device 10. The storage unit 12 stores the increased width product output cuff a at the input timing of the given data update command 22, and outputs this stored value to the contact point of the changeover switch 11. The changeover switch 11 closes contact a in synchronization with the start and stop of laser oscillation based on the ON-OFF signal 21. This is a switch that can be switched to b. Laser oscillation is stopped (
Since the signal from the detector 6 (dotted line part in Fig. 2) and therefore the amplified product output cuff a disappear, when the laser oscillation is turned off, the changeover switch 11 is turned on in advance in synchronization with this, that is, the memory 12 side to prevent disturbances in the laser power due to sudden changes (disappearance) of the input signal of the regulator 8. Note that the data update command 22 to the storage unit 12 is sent to the laser generator 1 by an ON-OFF signal 21 and a changeover switch 1.
When the selector switch 11 switches to the contact side, the storage section 12 stores the expanded product output cuff a immediately before this switching, that is, immediately before the laser generating section 1 is turned off. I remember. FIG. 2 is an explanatory diagram of the marking of the laser marker in FIG. 1. That is, when marking the letters A, B, and C as shown in Fig. 2, starting from a point PO other than the workpiece 5 and passing through points Pi and P2 on the way, mark the characters A, B, and C along the arrow route including dotted lines and solid lines (so-called - in the form of a brush stroke) laser beam L
Move B onto work 5. Here, the solid line part is the part where the laser generator 1 is turned on and marking is performed, and the dotted line part is the part where the laser generator 1 is turned off and the positioning mirror 4 operates during this time, but the laser beam LB is not irradiated onto the workpiece 5. It is. In Fig. 2, in order to improve the initial rise characteristics of the laser power, the point PO other than the workpiece 5 is irradiated with the laser for a certain period of time, and the laser oscillation is temporarily turned to 0FFL.
While retaining the laser power detection signal 5a immediately before FF, and therefore the enlarged product output cuff a, in the storage unit 12 (that is, the input to the regulator 8 remains constant even when the changeover switch 11 switches from contact a to contact b), Move the marking point to point P1, then turn on the laser oscillation and contact the changeover switch 11 to a, that is, switch the laser power detection input to the regulator 8 from the holding input to the actual input and mark the solid line part. , and thereafter, the dotted line portion and the solid line portion are similarly marked.

【Effect of the invention】

According to the invention, the laser reflector 2. a laser oscillation means composed of a laser output mirror 3 and a laser generation section 1 that generates laser light; a power detector 6 that extracts a part of the laser from the laser oscillation means and converts it into a laser power detection signal; and the laser power Detection signal 5a, therefore, enlarged product output cuff a
an adjuster 8 as a laser output control means for comparing the set value 9a of the setter 9 with the set value 9a of the setter 9 and controlling the laser oscillation means so that the two match. A laser processing apparatus is provided with a laser power control device 10, etc., and turns on and off the laser oscillation means via the ON-OFF signal 21 to perform a predetermined work. While the laser oscillation means is off, Since the control signal given by the laser output control means to the laser oscillation means is kept at the value immediately before turning off, the intensity of the laser obtained from the laser oscillation means is independent of the deterioration of the light source over time or changes in the environment. The laser oscillation means can be turned on automatically for marking without any manual intervention. Even when the power controller is turned off, there is no input fluctuation, so the power output does not fluctuate unstablely and high-quality markings can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a system configuration diagram of a laser marker as an embodiment of the present invention, and FIG. 2 is a diagram showing an example of marking based on the apparatus shown in FIG.

Claims (1)

[Claims] 1) Laser oscillation means comprising a laser reflection mirror, a laser output mirror, and a laser generation section that generates laser light; and a part of the laser light extracted from the laser oscillation means and used as a laser power detection signal. A power detecting means for converting the power, and a laser output controlling means for comparing the laser power detection signal with a set value and controlling the laser oscillating means so that the two match, and turning the laser oscillating means on and off to a predetermined value. A laser processing apparatus for performing the above operation, characterized in that while the laser oscillation means is turned off, the laser output control means maintains the control signal given to the laser oscillation means at the value immediately before the turning off. Processing equipment. 2) The laser processing apparatus according to claim 1 further comprises a detection signal holding means which holds the laser power detection signal immediately before turning off and supplies it to the laser output control means while the laser power oscillation means is turned off. A laser processing device comprising: 3) In the laser processing apparatus according to claim 2, the detection signal holding means is a memory that holds and outputs the laser power detection signal from the power detection means immediately before the laser oscillation means is turned off. and switching means for switching a laser power detection signal given to the laser output control means to the power detection means and the storage means, respectively, depending on whether the laser oscillation means is turned on or off. .