WO2023005224A1

WO2023005224A1 - Method for laser removal of cross-hole burrs

Info

Publication number: WO2023005224A1
Application number: PCT/CN2022/081567
Authority: WO
Inventors: 于晓东; 王传洋; 殷慧泽; 朱琦
Original assignee: 苏州大学
Priority date: 2021-07-27
Filing date: 2022-03-18
Publication date: 2023-02-02
Also published as: CN113500308A

Abstract

A method for the laser removal of cross-hole burrs, comprising the following steps: collecting an initial image of the interior of an on-site cross hole, and comparing the initial image with a reference image of the interior of a cross hole in a database, the cross hole in the reference image not having any burrs; according to the comparison result, determining the position in which a burr is located in the on-site cross hole; driving a laser head to move to above the burr in the on-site cross hole; and controlling the laser head to emit a laser on the position of the burr so as to remove the burr. The present method effectively increases burr removal efficiency and reduces manual labor intensity; in addition, the present method also effectively ensures the quality of burr removal, and does not easily damage products.

Description

A laser method for deburring cross holes

technical field

The invention relates to the technical field of burr removal, in particular to a laser method for removing burrs from cross holes.

Background technique

After the metal workpiece is machined, burrs tend to remain in the cross holes, and these burrs will have a great impact on the use of the workpiece. For example, for the crankshaft, a continuous and uniform oil film between the crankshaft and the connecting rod is conducive to ensuring the normal operation of the engine , so a continuous oil passage is processed on the crankshaft. Usually, the oil passage of the crankshaft is composed of two parts: a vertical hole and an inclined hole. There are usually burrs of different shapes and sizes left. On the one hand, the existence of these burrs will affect the flow of lubricating oil in the oil passage. In addition, due to the unstable connection between the burrs and the crankshaft base, the burrs are easy to break under high pressure during the operation of the engine. Under the action of the fluid, it falls off and turns into hard particles and enters the connection between the crankshaft and the connecting rod, causing abrasive wear on the crankshaft or connecting rod and reducing the life of the engine. In order to avoid the above problems, the product needs to be deburred.

Due to the deep position of the straight-inclined hole intersection inside the crankshaft oil passage, it is difficult to remove the burrs through automatic equipment. At present, mechanical grinding, chemical corrosion and electrochemical removal processes are generally used to remove burrs, but the efficiency of mechanical grinding is low. 1. The removal quality is not good and the labor intensity is high. The chemical corrosion and electrochemical removal methods not only remove the burrs, but also cause a certain degree of damage to the inner wall of the oil passage. At the same time, the application of chemical reagents will inevitably cause damage to the environment.

Therefore, the existing methods for removing burrs from intersecting holes have the problems of low removal efficiency, poor removal quality and easy damage to the product itself, which cannot meet the needs of use.

Contents of the invention

For this reason, the technical problem to be solved by the present invention is to overcome the defects of low removal efficiency, poor removal quality and easy damage to the product itself in the removal method of cross hole burrs in the prior art.

In order to solve the above-mentioned technical problems, the present invention provides a method for laser deburring of intersecting holes, comprising the following steps:

1) Collect the initial image inside the intersection hole on site, and compare the initial image with the reference image inside the intersection hole in the database. There is no burr in the intersection hole in the reference image. According to the initial image and the reference image Compare the results to determine the location of the burr in the cross hole on site;

2) Drive the laser head to move to the top of the burr in the cross hole on site;

3) Control the laser head to emit laser light to the burr position to remove the burr.

In one embodiment of the present invention, in the process of removing burrs in step 3), it is also necessary to start the blowing system to blow air into the on-site intersection holes to blow the fallen burrs away from the intersection holes.

In one embodiment of the present invention, after the step 3), the endoscopic probe is also inserted into the on-site intersection hole to see whether the burr removal in the on-site intersection hole meets the requirements.

In one embodiment of the present invention, the intersecting holes include intersecting vertical holes and oblique holes, and the laser head is provided with a plurality of laser distance measuring devices, and a plurality of reference points are taken on the vertical holes, each Each reference point corresponds to a laser distance measuring device. In step 2), after moving the laser head to the top of the vertical hole so that the laser head is located above the burr, the laser distance measuring device is also measured by each laser distance measuring device. The distance between the location of the device and the corresponding reference point, adjust the position of the laser head according to the difference in distance values measured by multiple laser distance measuring devices, so that the axis of the laser head is parallel to the axis of the vertical hole.

In one embodiment of the present invention, the movement of the laser head is controlled by a manipulator.

In one embodiment of the present invention, when controlling the laser head to emit laser light to the burr position in the step 3), it is also necessary to control the laser head to move according to a preset trajectory, and the preset trajectory includes a circular trajectory or an arc trajectory; The center of circle of described circular locus is positioned on the axis of vertical hole, and the maximum value of the radius of described circular locus is the radius of vertical hole, and the minimum value of the radius of circular locus is the radius of vertical hole and laser head emits The difference of the laser spot radius, the center of the arc track is located on the axis of the vertical hole, and the radius of the arc track is the radius of the vertical hole.

In one embodiment of the present invention, the laser emitted by the laser head is a continuous laser.

In one embodiment of the present invention, the laser emitted by the laser head is pulsed laser.

In one embodiment of the present invention, the pulse frequency of the pulsed laser is 100-150 GHz.

In one embodiment of the present invention, the initial image of the interior of the intersecting hole on site is captured by an endoscope camera.

The above technical solution of the present invention has the following advantages compared with the prior art:

The laser method for removing burrs from intersecting holes according to the present invention can effectively ensure the precise removal of burrs, improve the efficiency of burr removal, and reduce the labor intensity; and effectively ensure the quality of burr removal without causing damage to the product itself.

Description of drawings

In order to make the content of the present invention more clearly understood, the present invention will be further described in detail below according to the specific embodiments of the present invention and in conjunction with the accompanying drawings.

Fig. 1 is the schematic diagram of the position of intersecting hole among the present invention;

Description of reference signs in the manual: 1. crankshaft; 2. laser head; 3. laser distance measuring device; 4. cross hole.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, so that those skilled in the art can better understand the present invention and implement it, but the examples given are not intended to limit the present invention.

Embodiment one:

This embodiment discloses a method for laser deburring of cross holes. The crankshaft 1 is provided with a plurality of cross holes 4 (located on the oil passage). Refer to Fig. 1 for its position. The method includes the following steps:

1) Collect the initial image inside the on-site cross hole 4 on the crankshaft 1, and compare the initial image with the reference image inside the cross hole in the database. There is no burr in the cross hole in the reference image. According to the comparison result of the initial image and the reference image Extract the position of the burr in the cross hole 4 on site to realize the positioning of the burr;

Through the above method, the position of the burr can be accurately located, which is conducive to the precise removal of the subsequent burr, improves the effect of burr removal, and is beneficial to reduce the damage to the product itself;

2) Drive the laser head 2 to move above the burr in the cross hole 4 on site;

3) Control the laser head 2 to emit laser light to the burr position to remove the burr.

In one of the embodiments, in step 3) in the process of deburring, it is also necessary to start the blowing system to blow air in the cross hole 4 to blow the detached burrs away from the cross hole 4, so as to avoid the impact of the deburred fragments on the burrs. The inner wall of the crankshaft oil passage will be damaged again. In addition, the gas blowing system can also treat the gasified metal in the cross hole, and it can also avoid the damage of this part of the metal to the crankshaft oil passage.

Above-mentioned air blowing system can adopt high-pressure air blowing system.

In one of the embodiments, after step 3), the endoscopic probe is also inserted into the on-site intersection hole 4 to spy on whether the burr removal in the on-site intersection hole 4 meets the requirements, so as to detect the burr removal effect.

In one of the embodiments, the intersecting holes include intersecting vertical holes and oblique holes, and the vertical holes and oblique holes are interlinked. Head 4 is provided with a plurality of laser distance measuring devices 3, multiple reference points are taken on the vertical hole, each reference point corresponds to a laser distance measuring device, then in step 2) by moving the laser head to the vertical hole After the laser head is located above the burr, each laser distance measuring device needs to measure the distance between the position of the laser distance measuring device and the corresponding reference point, according to the distance value measured by multiple laser distance measuring devices Adjust the position of the laser head so that the axis of the laser head is parallel to the axis of the vertical hole, that is, to ensure that the end face of the laser head is perpendicular to the axis of the vertical hole, so as to better ensure the effect of laser deburring without Damage to the hole wall. At the same time, the relative distance between the laser head 2 and the burr can also be accurately measured by using the laser distance measuring device, so as to ensure the stability of the laser deburring process.

In one embodiment, the movement of the laser head 2 is controlled by a manipulator.

Furthermore, the manipulator is controlled by the robot control system, which can adjust the position of the manipulator according to the information of the burrs in the initial image inside the cross hole on site and the distance information measured by the laser distance measuring device, and can carry out The planning of the movement trajectory makes the laser head 2 move according to the preset trajectory, thereby realizing the automation of the deburring process.

In one embodiment, when controlling the laser head 2 to emit laser light to the burr position in step 3), it is also necessary to control the laser head 2 to move according to a preset trajectory, so as to better ensure the effect of burr removal.

The aforementioned preset trajectory includes a circular trajectory or an arc trajectory.

The center of the circular trajectory is located on the axis of the vertical hole, the maximum radius of the circular trajectory is the radius of the vertical hole, and the minimum radius of the circular trajectory is the radius of the vertical hole minus the laser spot emitted by the laser head The difference after the radius, the center of the arc track is located on the axis of the vertical hole, the radius of the arc track is the radius of the vertical hole, that is, the selected track point of the arc track is located on the inner wall of the vertical hole . Through the circular track and the arc track, the quality of burr removal can be effectively improved, and at the same time, the inner wall of the intersection hole is not easy to be damaged.

In one embodiment, the laser emitted by the laser head 2 is a continuous laser.

Continuous laser refers to the continuous output of the laser beam from the start of the laser head 2 until the laser head 2 is turned off.

It has been verified by experiments that under the parameters of the power of the laser head 2 of 600W-800W and the moving speed of 3mm/s-8mm/s, using continuous laser to remove the burrs in the crankshaft oil passage can effectively ensure the deburring effect, and the crossover after deburring The smoothness of the inner wall of the hole is better, and the time required for deburring is shorter.

In one of the embodiments, the initial image inside the on-site intersection hole 4 is obtained by taking an endoscope camera. The endoscope camera is an existing camera device. The endoscope camera is provided with a flexible probe that can be inserted into the High-resolution photographs were taken of the interior of Intersection Hole 4 to characterize the location of the burr.

Embodiment two:

The difference between this embodiment and the first embodiment is that the laser light emitted by the laser head 2 can also be a pulsed laser.

Pulse laser refers to the output of a beam of laser light at regular intervals.

In one embodiment, the pulse frequency of the pulsed laser is 100-150 GHz.

It has been verified by experiments that under the conditions of pulse laser power of 80W-100W, motion speed of 1mm/s-3mm/s, and pulse frequency of 100-150GHz, the use of pulse laser to remove burrs in crankshaft oil passage can also achieve better results. Deburring effect. The spot diameter of the pulsed laser is smaller, the action position is more precise, and the influence on the inner wall of the oil hole is also smaller.

The laser deburring method of the above-mentioned embodiment can accurately locate the burr position and use the laser to remove the burr, which effectively ensures the precise removal of the burr, improves the burr removal efficiency, and reduces the labor intensity; effectively ensures the quality of the burr removal, It is not easy to cause damage to the inner wall of the oil passage where the cross hole is located; the removal process does not require the use of chemicals, which is environmentally friendly.

Apparently, the above-mentioned embodiments are only examples for clear description, and are not intended to limit the implementation. For those of ordinary skill in the art, on the basis of the above description, other changes or changes in various forms can also be made. It is not necessary and impossible to exhaustively list all the implementation manners here. However, the obvious changes or changes derived therefrom are still within the scope of protection of the present invention.

Claims

A method for laser deburring of intersecting holes, characterized in that: comprising the following steps:

1) Collect the initial image inside the intersection hole on site, and compare the initial image with the reference image inside the intersection hole in the database. There is no burr in the intersection hole in the reference image. According to the initial image and the reference image Compare the results to determine the location of the burr in the cross hole on site;

2) Drive the laser head to move to the top of the burr in the cross hole on site;

3) Control the laser head to emit laser light to the burr position to remove the burr.
The method for removing burrs from intersecting holes by laser according to claim 1, characterized in that: in the process of removing burrs in said step 3), it is also necessary to start the air blowing system to blow air into the on-site intersecting holes to remove the fallen burrs Blow off cross holes.
The method for removing burrs from intersecting holes by laser according to claim 1, characterized in that: after said step 3), an endoscope probe is also inserted into the on-site intersecting holes to spy on whether the deburring situation in the on-site intersecting holes is Meet the requirements.
The method for deburring cross holes by laser according to claim 1, characterized in that: the cross holes include intersecting vertical holes and oblique holes, and the laser head is provided with a plurality of laser distance measuring devices. Multiple reference points are taken on the straight hole, and each reference point corresponds to a laser distance measuring device. In step 2), after moving the laser head to the top of the vertical hole so that the laser head is above the burr, each laser The distance measuring device respectively measures the distance between the location of the laser distance measuring device and the corresponding reference point, and adjusts the position of the laser head according to the difference in distance values measured by multiple laser distance measuring devices, so that the axis of the laser head and the vertical hole axes parallel to each other.
The method for deburring cross holes by laser according to claim 4, characterized in that: the movement of the laser head is controlled by a manipulator.
The method for removing burrs from intersecting holes by laser according to claim 4, characterized in that: when controlling the laser head to emit laser light to the burr position in the step 3), it is also necessary to control the laser head to move according to a preset track, and the preset The track includes a circular track or an arc track; the center of the circular track is located on the axis of the vertical hole, the maximum value of the radius of the circular track is the radius of the vertical hole, and the minimum value of the radius of the circular track is is the difference between the radius of the vertical hole and the radius of the laser spot emitted by the laser head, the center of the arc track is located on the axis of the vertical hole, and the radius of the arc track is the radius of the vertical hole.
The method for removing burrs from intersecting holes by laser according to claim 1, characterized in that: the laser emitted by the laser head is a continuous laser.
The method for removing burrs from intersecting holes by laser according to claim 1, characterized in that: the laser emitted by the laser head is pulsed laser.
The method for removing burrs from intersecting holes with laser according to claim 8, characterized in that: the pulse frequency of the pulsed laser is 100-150 GHz.
The method for deburring a cross hole by laser according to claim 1, characterized in that: the initial image inside the cross hole on site is captured by an endoscope camera.