JP2000084855A - Injection quantity measuring system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure the actual injection quantity of abrasive with extremely high accuracy by providing a laser sensor for irradiating laser beams in a direction intersecting the jet direction of abrasive partially extracted from an abrasive hose at an abrasive extraction part. SOLUTION: When abrasive 17 fed from an abrasive pressing tank passes an abrasive extraction part 20 installed at an intermediate part of an abrasive hose, part of the abrasive 17 is led in from an abrasive extraction port 21 and jetted from an abrasive jet tube 22. The abrasive jetted from the abrasive jet tube 22 is entirely sucked into an abrasive collection port 26. A laser sensor composed of a laser beam projecting part 23 and a laser beam receiving part 24 is so installed that laser beams 25 intersect abrasive 19 jetted from an abrasive jet port. The laser beams 25 are intercepted by the abrasive 19 so as to change the light quantity of the laser beams 25 entering the laser beam receiving part 24. This light quantity change is converted into the change of voltage by an amplifier unit, and the change of voltage is measured to measure the injection quantity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD OF THE INVENTION

[0002]

2. Description of the Related Art In recent years, precision processing such as fine engraving of ceramics and glass and formation of partition walls for plasma displays has been performed by blasting or sandblasting. For this reason, it has become very important to monitor the abrasive injection amount during processing.

Conventionally, as a method of measuring the injection amount during sandblasting, a polishing material flowing in a hose is irradiated with microwaves from the outside of the hose, and the polishing material flowing using a change in wavelength due to the Doppler effect is used. There is a way to measure the amount of

[0004] Here, the abrasives are not limited to metals and synthetic resins, but free particles including fine particles and fine powders used for any grinding or surface cleaning, and sandblasting are the abrasives such as the metals and the gas. And a means for injecting a solid-gas two-phase flow including so-called shot peening.

[0005]

In the above-mentioned means, particularly when the injection amount of the fine abrasive is measured, the normal injection amount is also 2.
Since the powder moving in the hose is as small as 00 to 400 g / min, the measurement cannot be performed unless a high sensitivity is set.

When the sensitivity is increased, the stability of the sensor deteriorates, and the injection amount is not proportional to the output from the sensor, so that it is difficult to display the injection amount. Therefore, it was only possible to measure the presence / absence of the abrasive injection, and it was impossible to specify how much abrasive was actually injected.

[0007]

DISCLOSURE OF THE INVENTION The present invention has been developed to solve the above-mentioned problems, and has a nozzle for ejecting an abrasive transferred from an abrasive recovery tank via a pipe, and the nozzle. In a blast apparatus for collecting abrasive after being sprayed to the abrasive recovery tank through an abrasive recovery piping system under negative pressure from a processing chamber main body to the abrasive recovery tank through an abrasive recovery conduit, A measuring abrasive extractor is provided in the pipe from the material recovery tank to the nozzle,
A laser sensor for irradiating a laser beam in a direction intersecting with a jetting direction of the abrasive material partially extracted from the abrasive hose in the abrasive material extracting section is provided, and the front of the jetting direction of the measuring abrasive material is polished. It is characterized by communicating with a material recovery piping system.

[0008] The laser sensor has a light projecting portion and a light receiving portion for laser light, and can measure an injection amount by outputting a variation in transmission amount of laser light as a voltage change via an amplifier unit. Further, one end of the abrasive collection port faces the front of the ejection direction of the measurement abrasive, and the other end is located at an arbitrary position of the abrasive collection pipe system, that is,
By connecting the processing chamber body to an arbitrary position of the abrasive recovery tank, the abrasive after measurement can be recovered. It is preferable that the measurement abrasive is collected from the main body of the processing chamber on a pipe by communicating with an abrasive collection conduit between the abrasive collection tanks.

Further, 0.1% or more and 10% or more of the amount of the abrasive transferred from the pipe including the abrasive hose from the abrasive recovery tank to the nozzle from the pipe including the abrasive hose.
The minimum amount of abrasive for measurement may be extracted by extracting less than abrasive in the abrasive extractor.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The system of the present invention is provided with an abrasive extraction section having an abrasive extraction port in a pipe from an abrasive recovery tank to a nozzle or in an abrasive hose to extract a part of the abrasive. The amount of the abrasive to be extracted is preferably less than 10% of the amount of the abrasive moving through the pipe or abrasive hose from the abrasive recovery tank to the nozzle, that is, less than 10% of the amount of abrasive injected from the nozzle during non-extraction. is there.

The actual injection amount is determined by applying a laser beam to the abrasive thus extracted and measuring the variation due to the attenuation factor of the laser beam.

In order to make this value correspond to the actually measured value of the abrasive sprayed from the nozzle, the data is corrected and displayed as the data of the injection amount, as described later. The abrasive blasting method of the blast device is a direct pressure type (Fig. 1) in which pressure is applied to the abrasive with high pressure air, and the abrasive is ejected from the nozzle. A suction type in which the abrasive is pulled in by the suction force using the ejector phenomenon and the abrasive is injected (Figure 2). In the direct pressure type, the inside of the abrasive material hose is pressurized, and in the suction type, the pressure is negative. Therefore, the specific configuration for extracting the abrasive is different.

Direct Pressure Type As shown in FIG. 1, in the direct pressure type, an abrasive recovery tank 40 is used.
In the above, the abrasive and the dust after the injection are separated, and the dust is sent to a dust collector 53 having an exhaust fan 54 via a duct 55, and the abrasive 33 drops down and accumulates in a lower portion of the abrasive recovery tank 40. . An abrasive pressurizing tank 42 is provided below the abrasive collecting tank 40. When the abrasive pressurized tank 42 runs out of abrasive, the dump valve 41 is lowered and the abrasive in the abrasive collecting tank 40 is pressed by the abrasive. Enter the tank 42. When the abrasive enters the abrasive pressurizing tank 42, the abrasive pressurized compressed air 47 enters through the abrasive pressurized compressed air supply port 44, and at the same time, the dump valve 41 closes and the pressure in the abrasive pressurized tank 42 increases. The abrasive is extruded from the abrasive supply port 43. At this time, the pressure of the abrasive pressurized compressed air 32 is adjusted by the abrasive supply amount adjusting valve 45, and the abrasive in the abrasive supply port 43 is supplied to the abrasive hose 1.
3 and is conveyed to the nozzle body 11 by the abrasive pressurized compressed air 32, and the abrasive is ejected from the nozzle tip 14.

In the case of such a direct pressure type, since the inside of the abrasive hose is pressurized, extremely, if the abrasive hose has a small hole, the abrasive blows out. What is necessary is just to measure the blown abrasive with a laser beam.

As shown in FIGS. 3 and 4, the abrasive 17 sent from the abrasive pressurizing tank 42 is
When entering, the abrasive passes through an abrasive extraction section 20 provided in the middle of the abrasive hose, and a part of the abrasive is introduced from an abrasive extraction port 21 and ejected from an abrasive ejection pipe 22. In the present embodiment, the abrasive extractor 20 is formed by forming the bottoms of the symmetrical substantially conical cylindrical bodies 62, 62 so as to face each other via the plate body 60 so as to have a spindle shape in cross section. An extraction passage 61 is formed in the plate body 60 located at the radial portion, and one end of the extraction passage 61 is opened rearward as the abrasive extraction port 21 in the abrasive transport direction. The abrasive material extraction port 21 can be provided at an arbitrary position in a diametrical cross section of the plate body 60 provided in the space where the abrasive material extraction part 20 is formed. By extracting the abrasive material from the center position of the cross section, The fluid resistance in the tube is small and the amount of extraction is stable. In addition, since the plate body 60 serves as a shield when the abrasive is transported in the nozzle direction, it is preferable to form the portion having the extraction passage 61 as small as possible. In the embodiment of the present invention, although not shown in the drawings, three abrasive injection channels 64 are respectively opened in one-third circle of the circular plate member 60, and the extraction passage is provided between two injection channels. 61 is formed. Alternatively, the extraction passage 61 may be formed as a pipe, and may be fixed to the abrasive hose or the cylinders 62, 62 provided in the abrasive hose by appropriate means, and each may be configured as the abrasive extractor 20.

In this case, the amount of the abrasive 19 ejected from the abrasive outlet is not more than 10% of the amount of the abrasive 17 transferred from the abrasive pressurizing tank 42. More preferably, if the amount is set to about 1%, the processing can be performed without reducing the injection amount of the abrasive 18 actually injected from the nozzle.

The abrasive spouted from the abrasive spout tube 22 is:
All are sucked into the abrasive material collecting port 26. Abrasive material collection port 2
Numeral 6 communicates with the abrasive recovery tank 40 or the processing chamber main body 50 or the dust collector 53 through the abrasive recovery conduit 52, and is blown out from the abrasive blowing pipe 22 because the exhaust air 54 has a negative pressure. All of the abrasives collected are collected. Laser light 25 and abrasive 19 exiting from abrasive outlet
Are arranged, and the laser beam projecting unit 23 and the laser beam receiving unit 24 are installed so that the laser beam 25 is blocked by the abrasive that has been ejected. Since the laser light 25 is blocked by the abrasive 19, the light quantity of the laser light 25 entering the light receiving portion 24 changes. Therefore, the injection amount is measured by changing this to a voltage change by an amplifier unit and measuring the voltage change. .

Example Test data In the case of an actual abrasive injection amount of 250 g / min.

Abrasive material diameter 2 mm Abrasive material ejected from abrasive material outlet: 2.58 g / mm Abrasive material used: Carborundum # 600 Output from amp unit: 3.5 V

In this test, when the injection amount of the abrasive from the nozzle was changed to 200 g / min, the amount of the abrasive ejected from the abrasive outlet changed to 2 g / min.

Further, the abrasive spray amount injected from the nozzle is set to 10
When it was changed to 0 g / min, the abrasive spouted from the abrasive spout changed to 1 g / min.

3 V when the injection amount is 200 g / min. 3 V when the injection amount is 150 g / min. 5V.

(Voltage value-1) × 100 = Injection amount is displayed.

In addition, it is also possible to configure such that an abnormal signal is generated below a certain numerical value together with the display of the injection amount and the operation of the blast device is stopped.

Suction type In FIG. 2, the outline of the suction type blasting apparatus is different from that of the direct pressure type. When the compressed air is injected into the suction injection nozzle 12 from the abrasive hose 31 communicating with the compressed air supply source. The inside of the nozzle 12 has a negative pressure, and the abrasive 33 in the abrasive recovery tank 34 is sucked into the nozzle 12 through the abrasive hose 13 by this negative pressure and is ejected from the nozzle tip 14.

As described above, in the case of the suction type blasting device, since the inside of the abrasive hose has a negative pressure, it is impossible to extract the abrasive only by providing a bypass in the abrasive hose. Aspirate the measurement abrasive. An ejector unit 30 that sends compressed air having substantially the same pressure as the compressed gas reaching the injection nozzle is used, and a part of the abrasive in the abrasive hose is extracted by the suction force.

The difference between the abrasive extractor and the direct pressure type will be described. As shown in FIGS. 5 and 6,
Here, an ejector pipe 27 that communicates with the abrasive extractor 20 via a hose (not shown) to a compressed air supply source is provided inside an ejector main body 28 having an abrasive outlet 22 ′ formed at the tip to form an ejector unit 30. The space between the outer wall of the ejector pipe 27 and the inner wall of the ejector main body communicates with the abrasive ejecting pipe 22 of the abrasive extracting unit 20 via a communication port 29 opened at the rear end of the ejector main body 28.

The position of the abrasive material extraction port 21 is preferably the center of the abrasive material extraction section 20, as in the direct pressure type.

The abrasive 16 sucked from the abrasive constant-quantity supply device 35 by the suction force of the nozzle 12 enters the abrasive hose 13 from the abrasive recovery tank 34, and the abrasive extractor provided in the middle of the abrasive hose. Enter 20.

A part of the abrasive entering the abrasive extractor 20 is sucked through the abrasive extractor 21 by the suction force of the compressed air sent to the ejector pipe 27 of the ejector unit 30. The sucked abrasive 19 is discharged from the space between the outer wall of the ejector pipe 27 and the inner wall of the ejector main body through the extraction passage 61, the abrasive ejection pipe 22 and the communication hole 29, and the abrasive outlet 22 ′ at the tip of the ejector unit 30. Erupts from

In this case, the amount of the abrasive 19 ejected from the abrasive outlet is preferably set to 10% or less of the amount of the abrasive 17 discharged from the abrasive recovery tank. More preferably 1%
If it is set to the extent, the processing can be performed without reducing the injection amount of the abrasive 16 actually injected from the nozzle more than necessary.

The abrasive spouted from the abrasive spout tube 22 is:
In this case as well, the whole is sucked into the abrasive material collecting port 26. The abrasive material collecting port 26 communicates with the cyclone 39 or the processing chamber body 50 or the dust collector 53 via the abrasive material collecting conduit 52 via a collecting tube 36 having one end communicating with the abrasive material collecting conduit 52. Since the pressure is negative, the abrasive spouted from the abrasive spout is collected.

As described above, when the laser light is blocked by the abrasive, the amount of light entering the light receiving portion of the laser light changes. This is changed to a change in voltage by the amplifier unit, and the change in voltage is measured to reduce the injection amount. Measure.

Example Test Data Diameter φ2 mm of air nozzle for ejector of ejector unit 30 Diameter φ4 mm of abrasive ejection port; actual abrasive injection amount 250 g / mm
in the case of.

Abrasive material outlet diameter 2 mm Abrasive material discharged from abrasive material outlet: 3.4 g / min Abrasive material used: Carborundum # 600 Output from amplifier unit: set to 3.5 V Abrasive material nozzle in this test 200 g / mm injection volume
When it is changed to 2, the abrasive ejected from the abrasive outlet is 2.
Changed to 7g / mm.

The amount of abrasive sprayed from the nozzle is set to 10
When it was changed to 0 g / min, the abrasive spouted from the abrasive spout changed to 1.4 g / mm.

Set to 3 V when the injection amount is 200 g / min. When the injection amount is 150 g / min. 5V.

The amount of injection is displayed on a personal computer as (volts−1) × 100.

The laser sensor used this time is LX2100, an ultra-compact laser discrimination sensor manufactured by Keyence Corporation.

Laser light source: semiconductor laser (visible light) wavelength 6
70nm detection range: φ1mm The amplifier unit uses LX2-60, and the laser light
Output with a voltage change of ~ 5V.

[0041]

As described above, according to the present invention, the actual injection amount of the abrasive can be measured with extremely high accuracy.

[Brief description of the drawings]

FIG. 1 is a diagram in which an injection amount measuring device is incorporated in a direct pressure type sand blast device.

FIG. 2 is a diagram in which an injection amount measuring device is incorporated in a suction type sand blast device.

FIG. 3 is a diagram of an injection amount measuring device for a direct pressure type sand blasting device.

FIG. 4 is a diagram of a part for measuring an amount of an abrasive by a laser beam;

FIG. 5 is a view of an ejector unit of an injection amount measuring device for a suction type sandblasting device.

FIG. 6 is a diagram of an injection amount measuring device for a suction type sandblasting device.

[Explanation of symbols]

 Reference Signs List 11 Direct pressure injection nozzle 12 Suction injection nozzle 13 Abrasive material hose 14 Nozzle tip 15 Air hose 16 Abrasive material from abrasive material supply device 17 Abrasive material coming out of abrasive pressure tank 18 Abrasive material sprayed from nozzle 19 Abrasive spouted from abrasive spout 20 Abrasive extractor 21 Abrasive extractor 22 Abrasive spout tube 22 'Abrasive spout 23 Laser light emitter 24 Laser light receiver 25 Laser light 26 Abrasive collector 27 Ejector pipe 28 Ejector main body 29 Communication pipe 30 Ejector unit 31 Air hose 32 Pressurized (compressed) air 33 Abrasive material 34 Abrasive material recovery tank 35 Abrasive material quantitative supply device 36 Collection tube 39 Cyclone 40 Abrasive material recovery tank 41 Dump valve 42 abrasive pressurized tank 43 abrasive supply port 44 abrasive Pressure compressed air supply port 45 abrasive supplying amount adjusting valve 47 abrasive pressurizing the compressed air 50 blasting machine 51 cabinet 52 abrasive recovery conduit 53 Dust collector 54 exhaust fan 60 plate body 61 extraction passage 62 the tubular body 64 injection passage

Claims (4)

[Claims] A nozzle for injecting the abrasive transferred from the abrasive recovery tank via a pipe; and a negative pressure from the processing chamber body having the nozzle to the abrasive recovery tank via an abrasive recovery conduit. A blasting device for collecting the abrasive after being sprayed to the abrasive recovery tank via the abrasive recovery pipe system, wherein a polishing abrasive extractor for measurement is provided in a pipe extending from the abrasive recovery tank to the nozzle; A laser sensor for irradiating a laser beam in a direction intersecting with a jetting direction of the abrasive material partially extracted from the pipe in the material extracting unit, and a polishing material collection pipe system in front of the jetting direction of the measuring abrasive material. An injection quantity measurement system, characterized in that it is connected to 2. The injection amount measurement system according to claim 1, wherein the laser sensor includes a laser light projecting unit and a light receiving unit, and outputs a variation in the transmission amount of the laser light as a voltage change via an amplifier unit. 3. An injection amount measuring system according to claim 1, wherein one end of an abrasive collecting port is made to face in front of the direction in which the abrasive for measurement is ejected, and the other end is connected to the abrasive collecting conduit. . 4. A polishing method comprising the step of transferring from 0.1% to less than 10% of the abrasive material transferred from the piping including the abrasive hose from the abrasive recovery tank to the nozzle from the piping including the abrasive hose. Claim 1 which extracts in an abrasive extraction part.
The injection amount measurement system according to 2 or 3.