TWI472393B - Method for surface cleaning of electrical discharge machining mold - Google Patents

Description

Electric discharge machining mold surface cleaning method

The invention relates to a method for cleaning the surface of an electric discharge machining mold, in particular to an electric discharge machining surface cleaning method for cleaning an electric discharge machining mold and activating the surface of the electric discharge machining mold to maintain product precision.

"Vacuum Plasma" and "Atmospheric Plasma" are all surface cleaning methods that have been widely used in various industries. Among them, for the cleaning method of the surface of the electric discharge machining mold, the effect of vacuum plasma cleaning is good, but it can The processed workpiece is limited by the form and size of the vacuum chamber of the vacuum plasma cleaning device, so that the process compatibility is low, and the yield is low and the equipment is expensive, which indirectly increases the manufacturing cost of the product. It is not suitable to clean the surface of the EDM mold by vacuum plasma cleaning.

In contrast, atmospheric plasma is in a normal pressure environment, using a high-energy electric field to dissociate the neutral gas into a plasma state, without the use of expensive vacuum chambers and vacuum systems; therefore, the surface of the current cleaning die is cleaned. The method is mainly based on the atmospheric plasma cleaning method with high process compatibility, fast and simple, low temperature and low cost.

However, the energy of atmospheric plasma cleaning is low. For the place where there is serious carbon deposit on the electric discharge machining mold, the effect of completely removing carbon deposit cannot be achieved; in the case of accumulated carbon accumulation, the coating yield of the product gradually increases. The deterioration causes the electric discharge machining mold to be eliminated after being used for a certain number of times, which is not only difficult to maintain the quality of the product, but also increases the manufacturing cost.

The object of the present invention is to solve the above disadvantages of the prior art, and to provide a method for cleaning the surface of an electric discharge machining mold, which can completely remove carbon deposits or dirt on the surface of the electric discharge machining mold by using a cleaning method of the laser composite atmospheric plasma. Improve surface cleanliness.

In order to achieve the foregoing object, the surface cleaning method for an electric discharge machining mold of the present invention comprises: a preliminary cleaning step of cleaning an electric discharge machining mold to be cleaned by wet cleaning, and drying the electric discharge machining mold after cleaning; a laser surface treatment step of placing at least one electric discharge machining mold after the preliminary cleaning step on a working platform of a dual-axis positioning device, and setting a travel path through the biaxial positioning device, and controlling the two-axis positioning device a laser device and a camera device are displaced relative to the working platform along the traveling path, and a laser is generated by the laser device when the surface of the at least one electric discharge machining mold is found to be carbonized or dirty through the imaging device. The light beam removes the carbon deposit or dirt; and an atmospheric plasma processing step cleans the surface of the at least one electrical discharge machining mold with an atmospheric plasma cleaning device.

The method for cleaning the surface of the electric discharge machining mold of the present invention further comprises a detecting step of checking whether the cleanliness of the surface of each of the electric discharge machining molds after the cleaning by the atmospheric plasma treatment step has reached an eligibility standard.

The method for cleaning the surface of an electric discharge machining die according to the present invention, wherein the travel path has a plurality of stagnation points, and when the camera device is aligned to each of the stagnation points, the relative displacement between the work platform and the camera device is suspended for a preset Time, and then continue to move along the migration path.

In the method for cleaning the surface of an electric discharge machining mold according to the present invention, the power of the laser beam is 3 to 100 W.

In the electric discharge machining mold surface cleaning method of the present invention, the atmospheric plasma cleaning device is mounted on the biaxial positioning device and opposed to the working platform.

The electric discharge machining mold surface cleaning method of the present invention, wherein the biaxial positioning device controls the atmospheric plasma cleaning device to generate a relative displacement with the working platform, and at the same time, the atmospheric plasma cleaning device injects the atmosphere into the at least one electric discharge machining mold Plasma.

The method for cleaning the surface of an electric discharge machining mold according to the present invention, wherein a relative displacement rate between the atmospheric plasma cleaning device and the working platform is 5 to 100 mm/second.

The surface cleaning method for the electric discharge machining mold of the present invention, wherein the working gas of the atmospheric plasma cleaning device is air, nitrogen, oxygen, argon or a mixed gas thereof, and the working voltage is 100 to 500V.

In the method for cleaning the surface of an electric discharge machining mold according to the present invention, wherein the electric discharge machining mold whose cleaning degree is not up to the qualified standard is detected by the detecting step, the laser surface treatment step and the atmospheric plasma treatment step are performed again to remove the surface. Carbon deposits or dirt until the cleanliness detected by this test step meets the eligibility criteria.

The surface cleaning method for an electric discharge machining die according to the present invention, wherein the wet cleaning comprises a degreasing and water washing process.

The above and other objects, features and advantages of the present invention will become more <RTIgt;

The "ultrasonic cleaning device" as used in the present invention refers to a person who is provided with a cleaning tank and can vibrate the liquid in the cleaning tank by ultrasonic waves to improve the cleaning efficiency.

The "oven" as used in the present invention refers to a person having a chamber and which can raise the temperature of the gas in the chamber by using a heat source such as electric heat or combustion heat, and can be used to evaporate the moisture of the articles placed in the chamber.

The "laser device" as used in the present invention refers to a laser beam that can be emitted from a nozzle to perform laser cleaning on the surface of the article; wherein the laser device suitable for use in the present invention can generate a wavelength range of 100 The laser beam of ~1200nm can adjust the power of the laser beam according to the demand.

The "two-axis positioning device" as used in the present invention refers to a working platform for erecting articles, and a processing base for erecting a preset processing device, and a moving path is set through a control unit to drive The working platform and the machining seat generate relative displacement along the travel path on the XY plane.

The "camera device" as used in the present invention refers to a person who can capture images in a preset range through a lens.

The "atmospheric plasma cleaning device" as used in the present invention means that the neutral gas can be dissociated into a plasma state by a high-energy electric field under normal pressure, and the working fluid is sprayed out of the plasma state through a nozzle to face the object. Carry out the cleaner.

The "water droplet contact angle measuring instrument" according to the present invention means that the angle between the water drop and the surface of the object can be measured, and the cleanness of the surface of the object can be judged.

Referring to FIG. 1, in a preferred embodiment of the present invention, the surface of the EDM mold cleaning method includes a preliminary cleaning step S1, a laser surface treatment step S2, and an atmospheric plasma treatment step S3 for cleaning. At least one of the surface of the electric discharge machining die 1 (shown in Fig. 2) is carbonaceous and/or dirty.

In the preliminary cleaning step S1 of the present invention, an electric discharge machining mold 1 to be cleaned is cleaned by wet cleaning, and the electric discharge machining mold 1 is dried after cleaning. More specifically, in order to improve the cleaning efficiency, the ultrasonic cleaning device may be subjected to a wet cleaning process such as degreasing and water washing in a cleaning tank through an ultrasonic cleaning device, and the cleaning tank is vibrated by ultrasonic waves. The liquid in the liquid improves the cleaning effect of the wet cleaning. In the degreasing process, the grease, the dirt, and the adhering matter adhering to the surface of the electric discharge machining die 1 are removed by a degreasing agent, and the degreasing agent remaining on the surface of the electric discharge machining die 1 is washed.

After the electric discharge machining die 1 is subjected to wet cleaning, the moisture on the electric discharge machining die 1 may be removed by means of natural air drying or heating baking; in this embodiment, in order to improve the efficiency of drying the electric discharge machining die 1, The electric discharge machining die 1 is placed in an oven, and is preferably heated at a temperature not exceeding 250 ° C for a suitable time to dry the electric discharge machining die 1 to complete the preliminary cleaning of the electric discharge machining die 1.

Referring to FIGS. 1 and 2, the laser surface treatment step S2 of the present invention performs laser surface treatment with a laser device 2 for carbon deposits or dirt on the surface of the at least one electric discharge machining mold 1. In more detail, at least one of the electric discharge machining molds 1 after the preliminary cleaning step S1 is placed on the working platform 31 of a biaxial positioning device 3; the laser device 2 is erected on the biaxial positioning a processing unit (not shown) of the device 3, and a high-magnification camera device 4 is disposed on the side of the laser device 2, and the camera device 4 is electrically connected to a display (not shown). The laser device 2 is electrically connected to the display device (not shown). The nozzle 21 and the lens 41 of the camera 4 are opposite to the working platform 31 and spaced apart from the working platform 31 by a predetermined distance. Wherein, the laser device 2 in this embodiment can be selected to emit a laser beam having a wavelength of 532 nm.

Furthermore, an appropriate travel path R1 can be set by the control unit of the biaxial positioning device 3 according to the number of EDMs 1 placed on the work platform 31. For example, when the number of the electric discharge machining molds 1 placed on the work platform 31 is a single one, it is preferable to set the travel path R1 to a continuous path around the electric discharge machining mold 1, for example, 3a, 3b, but not limited to this; when the number of electric discharge machining dies 1 placed on the working platform 31 is plural, the travel path R1 can be set to be individually for each electric discharge machining mold. 1 The bypass is completed, and the transition path R1 may be set as a continuous path spanning the plurality of electric discharge machining dies 1, for example, as shown in FIGS. 2 and 3c, but not limited thereto.

The operation temperature of the laser surface treatment step S2 can be selected as room temperature, and the laser device 2 and the camera device 4 are precisely controlled by the biaxial positioning device 3 through the foregoing structure, and the working platform 31 is A relative displacement is generated along the preset travel path R1 on the XY plane; wherein the work platform 31 can be kept stationary, the laser device 2 and the camera device 4 are driven to generate displacement, or the laser device 2 and the camera device 4 are caused to be displaced. Staying still, driving the work platform 31 to produce displacement.

In addition, since the lens 41 of the camera device 4 can only capture images within a preset range, a plurality of stagnation points P can be set on the travel path R1 through the control unit of the dual-axis positioning device 3. When the device 4 is aligned to each stagnation point P, the relative displacement between the working platform 31 and the camera device 4 will pause for a dwell time, and then continue to be displaced along the travel path R1; wherein the dwell time may be 0.5~5 Seconds, preferably 1 second.

According to this, the user can immediately observe the position where the surface of the electric discharge machining mold 1 is photographed by the display device 4; if a serious carbon deposit or dirt is seen at a stagnation point P, the pair can be The control unit of the biaxial positioning device 3 pauses the command to pause the relative displacement between the working platform 31 and the camera device 4, and controls the laser device 2 to emit power of 3 to 100 W (preferably 35 W). The laser beam is cleaned against the severe carbon deposit or dirt to locally remove carbon deposits or dirt on the electric discharge machining die 1. Through the arrangement of the camera device 4, the laser device 2 can be precisely cleaned only for carbon deposits or dirt, so that the high-energy laser beam does not sweep through places where there is no carbon deposit or dirt. The surface of the electric discharge machining die 1 can be effectively prevented from being damaged, thereby prolonging the service life of the electric discharge machining die 1.

After the carbon deposit or the dirt on the electric discharge machining die 1 is removed at the stagnation point P, the pause command can be released, and the relative displacement between the working platform 31 and the image pickup device 4 along the travel path R1 can be continued. When the camera unit 4 is aligned to the next stagnation point P, it will be temporarily stopped for observation to see if there is a need for laser cleaning, and so on until the check of all the stagnation points P on the travel path R1 is completed.

Referring to FIGS. 1 and 4, the atmospheric plasma processing step S3 of the present invention cleans the surface of the at least one electric discharge machining die 1 with an atmospheric plasma cleaning device 5. In more detail, the atmospheric plasma cleaning device 5 can also be mounted on the processing seat of the biaxial positioning device 3, and the nozzle 51 of the atmospheric plasma cleaning device 5 is also opposite to the working platform 31 and spaced apart by a predetermined distance. And a suitable travel path R2 can be set by the control unit of the biaxial positioning device 3, and the travel path R2 can be the same as or different from the travel path R1.

According to this, after the surface of the at least one electric discharge machining die 1 passes through the laser surface treatment step S2 to partially remove the serious carbon deposit or dirt, the atmospheric plasma cleaning device 5 can be precisely controlled by the biaxial positioning device 3 and The working platforms 31 are relatively displaced along the predetermined travel path R2 on the XY plane, and the atmospheric plasma cleaning device 5 simultaneously injects atmospheric plasma into the at least one electric discharge machining die 1 on the working platform 31. To comprehensively remove residual carbon deposits or dirt on the surface of the at least one electric discharge machining mold 1.

In this embodiment, the operating temperature of the atmospheric plasma processing step S3 may also be selected as room temperature, and the working gas of the atmospheric plasma cleaning device 5 may be air, nitrogen, oxygen, argon or a mixed gas thereof. The working voltage may be 100~500V (preferably 250V), and the relative displacement rate between the atmospheric plasma cleaning device 5 and the working platform 31 may be 5~100 mm/second (preferably 20 mm/second).

Referring to FIG. 1 , the present invention preferably further includes a detecting step S4 for checking whether the cleanliness of the surface of each of the EDM 1 after cleaning by the atmospheric plasma processing step S3 has been Meet the eligibility criteria. More specifically, it is optional to detect the surface of the electric discharge machining die 1 by the "water droplet contact angle test method", and whether it has passed the cleaning process after the laser surface treatment step S2 and the atmospheric plasma treatment step S3. a cleanliness standard; that is, a fixed volume of liquid deionized water droplets may be sprinkled on the surface of the electric discharge machining die 1 and measured by a water droplet contact angle measuring instrument to measure the angle between the water drop and the surface of the electric discharge machining die 1. The cleanliness of the surface of the electric discharge machining die 1 is judged by the criterion of "the higher the degree of cleanliness, the smaller the contact angle of the water droplets".

In addition, for the electric discharge machining die 1 whose cleaning degree is not up to the qualified standard, the laser surface treatment step S2 and the atmospheric plasma treatment step S3 may be performed again to remove carbon deposits or dirt on the surface until the detection step S4 is performed. The cleanliness is tested to the eligibility criteria.

Please refer to the attached pictures 1~3. The pictures 1~3 are respectively "before cleaning", "cleaning only with atmospheric plasma" and "cleaning with laser composite atmospheric plasma". The test results obtained by the water droplet contact angle test were performed at the same position of the electric discharge machining mold. It can be seen from the attachment 1 that the discharge machining mold before cleaning has a water droplet contact angle of more than 70 degrees on the surface; the discharge machining mold of the surface of the electric discharge machining mold which has been cleaned by the atmospheric plasma has been reduced to less than about 20 degrees; However, in the electric discharge machining mold which has been cleaned by the laser composite atmospheric plasma, the contact angle of the water droplet on the surface can be even less than 10 degrees. Therefore, the surface cleaning method of the electric discharge machining mold of the present invention can effectively improve the surface cleanliness of the electric discharge machining mold.

In summary, the surface cleaning method of the electric discharge machining mold of the present invention can completely remove the carbon deposit or the dirt on the surface of the electric discharge machining mold by using a cleaning method of the laser composite atmospheric plasma to improve the surface cleanliness. Increasing the coating yield of the product and extending the service life of the EDM mold not only maintains the quality of the product, but also reduces the manufacturing cost.

While the invention has been described in connection with the preferred embodiments described above, it is not intended to limit the scope of the invention. The technical scope of the invention is protected, and therefore the scope of the invention is defined by the scope of the appended claims.

1. . . Electric discharge machining mold

2. . . Laser device

twenty one. . . Nozzle

3. . . Dual axis positioning device

31. . . Work platform

4. . . Camera

41. . . Lens

5. . . Atmospheric plasma cleaning device

51. . . Nozzle

S1. . . Initial cleaning step

S2. . . Laser surface treatment steps

S3. . . Atmospheric plasma treatment steps

S4. . . Detection step

R1. . . Migration path

R2. . . Migration path

P. . . Stagnation point

Figure 1 is a block diagram showing the flow of a preferred embodiment of the present invention.

Figure 2: Schematic diagram of the laser surface treatment steps of the present invention.

Figure 3a is a schematic view of the path of the relative displacement of the camera device of the present invention and the working platform (1).

Figure 3b is a schematic diagram of the path of the relative displacement of the camera device of the present invention and the working platform (2).

Figure 3c: Schematic diagram of the path of the relative displacement of the camera device of the present invention and the working platform (3).

Figure 4: Schematic diagram of the atmospheric plasma treatment steps of the present invention.

Attachment 1: The test result of the water droplet contact angle test before the surface of the electric discharge machining mold is cleaned.

Attachment 2: The surface of the EDM mold was cleaned only by atmospheric plasma and tested for water droplet contact angle test.

Attachment 3: The surface of the EDM mold was cleaned by a laser composite atmospheric plasma and tested for water droplet contact angle test.

S1. . . Initial cleaning step

S2. . . Laser surface treatment steps

S3. . . Atmospheric plasma treatment steps

S4. . . Detection step

Claims (9)

A method for cleaning a surface of an electric discharge machining mold, comprising: a preliminary cleaning step of cleaning an electric discharge machining mold to be cleaned by wet cleaning, and drying the electric discharge machining mold after cleaning; a laser surface treatment step, at least After the preliminary cleaning step is completed, the electric discharge machining mold is placed on a working platform of a dual-axis positioning device, and a travel path is set through the dual-axis positioning device, and a laser device and a camera device are controlled by the dual-axis positioning device. The traveling path is displaced relative to the working platform, and when the surface of the at least one electric discharge machining mold is found to have carbon deposits or dirt through the imaging device, a laser beam is generated by the laser device to remove the carbon deposit or dirt. And an atmospheric plasma processing step of cleaning the surface of the at least one electric discharge machining mold by an atmospheric plasma cleaning device; wherein the travel path has a plurality of stagnation points, when the camera device is aligned to each of the stagnation points, The relative displacement between the working platform and the camera will be paused for a predetermined time and then continued to be displaced along the path. The method for cleaning the surface of an electric discharge machining mold according to claim 1, further comprising a detecting step of checking whether the cleanliness of the surface of each of the electric discharge machining molds after cleaning by the atmospheric plasma processing step has reached Eligibility criteria. The method for cleaning the surface of an electric discharge machining mold according to claim 1 or 2, wherein the power of the laser beam is 3 to 100 W. EDM surface as described in claim 1 or 2 The cleaning method, wherein the atmospheric plasma cleaning device is mounted on the biaxial positioning device and is opposite to the working platform. The method of cleaning an electric discharge machining surface according to claim 4, wherein the biaxial positioning device controls the atmospheric plasma cleaning device to generate a relative displacement with the working platform, and at the same time, the atmospheric plasma cleaning device At least one electric discharge machining die ejects atmospheric plasma. The method for cleaning the surface of an electric discharge machining mold according to claim 5, wherein a relative displacement rate between the atmospheric plasma cleaning device and the working platform is 5 to 100 mm/second. The method for cleaning the surface of an electric discharge machining mold according to the fourth aspect of the invention, wherein the working gas of the atmospheric plasma cleaning device is air, nitrogen, oxygen, argon or a mixed gas thereof, and the working voltage is 100 to 500V. The method for cleaning the surface of an electric discharge machining mold according to the second aspect of the invention, wherein, in the detecting step, the electric discharge machining mold having the cleanliness that does not meet the qualified standard is detected, and the laser surface treatment step and the atmospheric plasma are performed again. A processing step to remove carbon deposits or dirt from the surface until the cleanliness detected by the detection step meets the eligibility criteria. The method of cleaning an electric discharge machining surface according to claim 1, wherein the wet cleaning comprises a degreasing and water washing process.