CN212470232U

CN212470232U - Photoelectric detection device for laser penetration detection and corresponding laser cutting head

Info

Publication number: CN212470232U
Application number: CN202021019142.XU
Authority: CN
Inventors: 朱天凤; 丁海; 许佰鹏
Original assignee: Shanghai Weihong Automation Technology Co ltd; SHANGHAI WEIHONG ELECTRONIC TECHNOLOGY CO LTD; Shanghai Weihong Intelligent Technology Co ltd
Current assignee: Shanghai Weihong Automation Technology Co ltd; SHANGHAI WEIHONG ELECTRONIC TECHNOLOGY CO LTD; Shanghai Weihong Intelligent Technology Co ltd
Priority date: 2020-06-05
Filing date: 2020-06-05
Publication date: 2021-02-05
Anticipated expiration: 2030-06-05

Abstract

The utility model relates to a photoelectric detection device and a corresponding laser cutting head for laser penetration detection, wherein, the device comprises a reflector with a light gathering function and a light receiving and detecting module, the reflector with the light gathering function is positioned in the light path of laser; the reflector with the light condensation function condenses and reflects heat radiation light generated by interaction of a workpiece and laser to the light receiving and detecting module, and the light receiving and detecting module is used for detecting the heat radiation light. By adopting the photoelectric detection device for laser penetration detection and the corresponding laser cutting head, the process of laser cutting head operation can be monitored by detecting the thermal radiation light, the laser cutting efficiency and the cutting quality are effectively improved, the laser cutting head is protected, the service life of a laser is effectively prolonged, and the photoelectric detection device has the characteristics of good performance and low cost.

Description

Photoelectric detection device for laser penetration detection and corresponding laser cutting head

Technical Field

The utility model relates to a laser beam machining technical field especially relates to laser cutting's photoelectric detection technical field, specifically indicates a photoelectric detection device and corresponding laser cutting head that is used for laser to pierce through detection.

Background

At present, when a laser cutting head carries out perforation or cutting operation, open operation is generally adopted. That is, the punching or cutting time is generally set longer than the actual working time to ensure that the material is processed normally, but this often results in waste of resources and time. When the cutting parameter is set unreasonably, the abnormal phenomena such as hole bursting or imperviousness cutting and the like often occur, and the cutting quality is influenced. When stainless steel, aluminum plate and other materials with high reflectivity are cut, a workpiece can reflect a large amount of laser to a laser when the material is cut, and the laser is greatly damaged.

SUMMERY OF THE UTILITY MODEL

The utility model discloses an overcome at least one above-mentioned prior art's shortcoming, provide a photoelectric detection device and corresponding laser cutting head that is used for laser to pierce through detection that the performance is good, increase equipment life.

In order to achieve the above object, the utility model discloses a photoelectric detection device and corresponding laser cutting head for laser pierces through detection has following constitution:

the photoelectric detection device for laser penetration detection is mainly characterized by comprising a reflector with a light gathering function and a light receiving and detecting module, wherein the reflector with the light gathering function is positioned in a light path of laser;

the reflector with the light condensation function condenses and reflects heat radiation light generated by interaction of a workpiece and laser to the light receiving and detecting module, and the light receiving and detecting module is used for detecting the heat radiation light.

Preferably, the reflector with the light condensing function is coaxial with the laser, and an included angle between a reflecting surface of the reflector with the light condensing function and a heat radiation light receiving surface of the light receiving and detecting module is a preset angle, so that the reflector with the light condensing function can reflect the heat radiation light to the heat radiation light receiving surface of the light receiving and detecting module.

Preferably, each small reflection surface of the reflector with the light condensing function has a specific reflection angle.

Preferably, the light receiving and detecting module includes a filter and a photosensor, and the thermal radiation light is transmitted to the photosensor through the filter.

Preferably, the reflector with the light-gathering function is of a metal structure.

The laser cutting head comprising the photoelectric detection device is mainly characterized by further comprising a nozzle, a protective lens and a focusing lens, wherein the photoelectric detection device is located between the protective lens and the focusing lens, the nozzle is located below the protective lens, and the light receiving and detecting module is connected with a master control system.

The laser cutting head comprises a nozzle, a collimating lens and a focusing lens, wherein the photoelectric detection device is positioned between the collimating lens and the focusing lens, the nozzle is positioned below the focusing lens, and the light receiving and detecting module is connected with a master control system.

Adopt this utility model's a photoelectric detection device and corresponding laser cutting head for laser pierces through detection, the accessible is to the detection of thermal radiation light, monitors the process of laser cutting head operation, effectively improves laser cutting efficiency, cutting quality, protects, effectively increases the life of laser instrument to the laser cutting head, possesses the characteristics of functional, with low costs.

Drawings

Fig. 1 is a schematic view of an optical path of a laser cutting head according to an embodiment of the present invention.

FIG. 2 is a top view of a first specially made mirror.

FIG. 3 is a schematic diagram of a first specially-made reflector design.

Fig. 4 is a graph illustrating the corresponding electrical signal curves of the thermal radiation light under different conditions.

Reference numerals

1 first special reflector with light-gathering function

1-1 small reflecting surfaces

1-2 middle light-through hole of first special reflector

1-3 mounting surface of first special reflector

2 optical filter

3 photoelectric sensor

4 focusing mirror

5 protective glasses

6 heat radiation light

7 nozzle

8 workpiece

9 laser

Detailed Description

In order to more clearly describe the technical content of the present invention, the following further description is given with reference to specific embodiments.

As shown in fig. 1, in this embodiment, the photoelectric detection apparatus for laser penetration detection includes a first special reflector 1 with a light-gathering function and a light receiving and detecting module, where the first special reflector 1 with a light-gathering function is located in the optical path of laser light 9;

the first special reflector 1 with the light gathering function gathers and reflects the heat radiation light 6 generated by the interaction of the workpiece 8 and the laser 9 to the light receiving and detecting module, and the light receiving and detecting module is used for detecting the heat radiation light 6.

In this embodiment, the first special reflecting mirror 1 with the light condensing function is coaxial with the laser 9, and an included angle between a reflecting surface of the first special reflecting mirror 1 with the light condensing function and a heat radiation light 6 receiving surface of the light receiving and detecting module is a preset angle, so that the first special reflecting mirror 1 with the light condensing function can reflect the heat radiation light 6 to the heat radiation light 6 receiving surface of the light receiving and detecting module.

In this embodiment, each small reflective surface of the first special reflector 1 with a light condensing function has a specific reflection angle.

In this embodiment, the light receiving and detecting module includes a filter 2 and a photosensor 3, and the thermal radiation light 6 is transmitted to the photosensor 3 through the filter 2.

In this embodiment, the reflector with a light condensing function is a metal structure.

Fig. 1 shows a laser cutting head including the above photoelectric detection device, which further includes a nozzle 7, a protective lens 5 and a focusing lens 4, the photoelectric detection device is located between the protective lens 5 and the focusing lens 4, the nozzle 7 is located below the protective lens 5, and the light receiving and detecting module is connected with a main control system.

In other embodiments, the laser cutting head including the above-mentioned photoelectric detection device may include a nozzle 7, a collimating mirror and a focusing mirror 4, the photoelectric detection device may also be located between the collimating mirror and the focusing mirror 4, the nozzle 7 is located below the focusing mirror 4, and the light receiving and detecting module is connected with the main control system.

Namely, the photoelectric detection device in the above embodiment can be used in the laser cutting head, between the laser focusing lens 4 and the protection lens 5, and between the collimating lens and the focusing lens 4, and has certain flexibility in arrangement.

In the working process of the laser cutting head, the laser 9 beams focused by the focusing mirror 4 and the heat radiation light 6 generated by the action of the workpiece 8 radiate to the periphery, and part of the heat radiation light 6 passes through the nozzle 7 and the protective mirror 5 and reaches the first special reflector 1 with the light condensing function. The first special reflector 1 with the light gathering function is composed of a plurality of small reflecting surfaces, as shown in fig. 2, a top view of the first special reflector 1 with the light gathering function is shown, and 1-1 is composed of two circles of small reflecting surfaces and used as reflecting surfaces for reflecting radiation light. 1-2 is the central clear aperture of the first special reflector 1, allowing the laser to pass without affecting the normal function of the cutting head. Fig. 2 is a diagram showing only two small circles of mirrors, and the size and number of the mirrors can be set as desired. 1-3 are the bases of the first tailored mirror 1, which do not function to the actual reflection side, as mounted on the cutting head. Each small reflecting surface has a specific deflection angle, as shown in fig. 3, a connecting line AB of a point A about 1mm below the center of the nozzle and a central point B of a certain small reflecting surface, a connecting line CB of a center C of the photoelectric sensor and a central point B of a certain small reflecting surface, and BO is a bisector of ═ ABC formed by AB and CB. Vector quantity

I.e. the normal vector of the small reflecting surface, the small reflecting surface is located at

And point B. The other small reflecting surfaces are designed according to the same principle. And the small reflecting surfaces are polished with high precision, and can reflect most of the received radiation light to the optical filter 2. The filter 2 functions to reflect light from the laser,the light transmittance is below 0.00001%, but the light transmittance is higher for the light not in the laser band, so that the ratio of the intensity of the radiation light and the laser light received by the photoelectric sensor 3 is enhanced, and the contrast of the signal is improved. The photoelectric sensor 3 receives a thermal radiation signal, converts an optical signal into a current signal, and finally feeds the signal back to the master control system.

Fig. 1 is the light path schematic diagram of laser cutting head in the utility model provides a direction sign light transmission direction of arrow in the picture, as shown in the figure, focusing mirror 4 focuses on work piece 8 with laser, and work piece 8 and laser interact produce heat radiation light 6. Part of the heat radiation light 6 enters the cutting head from the spray nozzle 7, and the radiation light is reflected by the first special reflector 1 with the light gathering function after passing through the lower protective mirror and finally enters the light receiving and detecting module (the optical filter 2 and the photoelectric sensor 3). The photoelectric sensor 3 converts the optical signal into an electric signal to be output, and finally transmits the signal to a master control system to control the action of the cutting head.

As shown in fig. 1, the photodetection device in this embodiment has a simple structure, can be designed compactly as needed, and is easy to realize modularization. Meanwhile, the first special reflector 1 with the light-gathering function can be machined by metal, so that the difficulty and cost of machining and polishing are considered, each small reflecting surface can be designed and machined into a plane, and the implementation is easy. The structure can work between the protective lens 5 and the focusing lens 4 of the laser cutting head and also can work between the collimating lens and the focusing lens 4.

When the laser cutting head works, the first special reflector 1 with the light gathering function reflects the heat radiation light 6 to the sensor. When the workpiece 8 penetrates, the heat radiation light 6 is attenuated until it disappears. After the heat radiation light 6 disappears, the electric signal output by the photoelectric sensor 3 tends to be stable, the main control system identifies the change trend of the signal, judges whether the workpiece 8 is penetrated, controls the cutting head to enter the cutting process, prevents the workpiece from being burnt excessively, saves the operation time, and improves the working efficiency and the cutting quality. When a high-reflectivity plate is cut, if the phenomena of hole explosion, imperviousness in cutting and the like occur, the sensor receives an abnormal signal and feeds the abnormal signal back to the master control system, so that the laser is controlled to stop emitting light, and the laser is protected.

Fig. 4 is a graph illustrating the corresponding electrical signal curves of the thermal radiation light under different conditions, as shown in the figure, the laser is not turned on at the time 0-t 1. No valid signal is output for this period. At time t1, the laser is turned on and the laser operating mode uses a laser output with a duty cycle of about 90%. After the laser is started, the laser acts on the plate, and the sensor receives signals. t1-t2 is the perforation phase, at time t2 the hole is penetrated, but the laser is not turned off. the cutting head moves to the following position in preparation for cutting by operating the cutting head Z shaft and the cutting head W shaft at the stage of t2-t 3. Cutting is started at the time t3, and the laser light emitting uses 100% duty cycle. t3-t6 is the cutting process, and t6 is the laser off. the abnormal rise of the signal amplitude occurs at the time t4-t5, because the phenomenon that the plate is not cut through occurs, the reflected laser of the plate is responded by the sensor, and the amplitude of the electric signal output by the sensor rises.

Therefore, the laser cutting head can detect the cutting state through the thermal radiation light detected by the photoelectric detection device during working, so that the cutting state is better controlled, the cutting quality is ensured, and the purposes of improving the efficiency and saving energy are achieved.

The utility model discloses an among photoelectric detection device and corresponding laser cutting head technical scheme for laser pierces through detection, each functional module and the modular unit that wherein include all can correspond to the specific hardware circuit in the integrated circuit structure, consequently only relate to the improvement of specific hardware circuit, and the hardware part is not merely the carrier that belongs to execution control software or computer program, consequently solves corresponding technical problem and obtains corresponding technical effect and also does not relate to the application of any control software or computer program, that is to say, the utility model discloses only utilize the improvement in the aspect of the hardware circuit structure that these modules and units relate to can solve the technical problem that will solve to obtain corresponding technical effect, and need not assist and can realize corresponding function with specific control software or computer program.

In this specification, the invention has been described with reference to specific embodiments thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of the invention. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.

Claims

1. The photoelectric detection device for laser penetration detection is characterized by comprising a reflector with a light-gathering function and a light receiving and detecting module, wherein the reflector with the light-gathering function is positioned in the light path of laser;

2. The photodetection device according to claim 1, wherein the reflector with condensing function is coaxial with the laser light, and an angle between a reflection surface of the reflector with condensing function and a thermal radiation light receiving surface of the light receiving and detecting module is a predetermined angle, so that the reflector with condensing function can reflect the thermal radiation light to the thermal radiation light receiving surface of the light receiving and detecting module.

3. The photodetection device according to claim 2, characterized in that the reflecting surface of the reflector with light condensing function is composed of several circles of small reflecting surfaces, each reflecting surface having a specific reflecting angle.

4. The photodetection device according to claim 2, wherein the light receiving and detecting module comprises a filter and a photosensor, and the thermal radiation light is transmitted to the photosensor through the filter.

5. The photodetection device according to claim 1, wherein the reflector with light condensing function is a metal structure.

6. A laser cutting head comprising the photoelectric detection device of any one of claims 1 to 5, wherein the laser cutting head further comprises a nozzle, a protective lens and a focusing lens, the photoelectric detection device is positioned between the protective lens and the focusing lens, the nozzle is positioned below the protective lens, and the light receiving and detecting module is connected with a main control system.

7. A laser cutting head comprising the photoelectric detection device of any one of claims 1 to 5, wherein the laser cutting head further comprises a nozzle, a collimating mirror and a focusing mirror, the photoelectric detection device is positioned between the collimating mirror and the focusing mirror, the nozzle is positioned below the focusing mirror, and the light receiving and detecting module is connected with a main control system.