JP2007130716A - Method and device for generating abrasive water jet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To restrain variation of cutting performance of an abrasive water jet cutter. <P>SOLUTION: According to this method for generating abrasive water jet, an opening of an abrasive throttle device 4 provided in an abrasive supply passage 7 to a nozzle device 1 of the abrasive water jet cutter is adjusted to obtain a desired abrasive supply quantity for obtaining desired cutting performance, and abrasive in an abrasive storage tank 3 is supplied through an abrasive throttle device 4 to the nozzle device 1. On the other hand, a time change of mass of abrasive in the abrasive storage tank 3 is detected according to the measurement result of a load cell 5 receiving the abrasive storage tank 3, an abrasive supply quantity per unit time in measurement is obtained from the measurement result, and an opening of a compressed air throttle device 11 in a compressed air supply passage 12 force-feeding the abrasive to the nozzle device 1 is varied to adjust the supply quantity of the abrasive to the nozzle device 1. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method and an apparatus for generating an abrasive water jet used in an abrasive water jet cutting method, and particularly relates to an apparatus that employs a form in which abrasive particles, which are abrasive particles, are pressure-fed and supplied to a nozzle device.

  The abrasive water jet cutting method is generally used for cutting and forming concrete, stone, and steel materials.

  In this abrasive water jet cutting method, the abrasive water jet discharged from the nozzle device is cut and collided with an object to be formed, and the object is cut and formed.

  This abrasive water jet is generated as follows. That is, the liquid pressurized by the ultra high pressure water pump is squeezed by the restriction in the nozzle device to generate an ultra high pressure water jet. On the other hand, abrasives, which are abrasive particles, are supplied into the nozzle device, and abrasive particles are mixed with the water jet in a mixing region in the nozzle to generate an abrasive water jet.

  As a method of feeding the abrasive to the mixing area with the water jet, there are a pressure feeding method for supplying the abrasive together with the compressed air, and a natural method for supplying the abrasive into the nozzle apparatus by the negative pressure generated in the nozzle apparatus by the water jet injection. A suction method is known.

  The above two methods are described in Patent Document 1 as a method for supplying abrasive particles to the mixed region. In this patent document 1, when the mixing region is further wetted, only compressed air is mixed prior to the generation of the abrasive water jet as a countermeasure against the problem that the flowability of the abrasive particles to be supplied decreases in the nozzle device. And drying the mixing zone before supplying abrasive particles into the mixing zone.

Japanese Examined Patent Publication No. 4-31823

  What is shown in Patent Document 1 is merely a method of feeding abrasive particles to a mixing region, and does not capture problems that occur in those methods or means. There are the following two problems.

  First, in the pressure feeding system, since the abrasive is pumped by compressed air, it is possible to feed over a long distance. However, if the supply amount of compressed air is not set appropriately, the abrasive is stable due to the resistance of the path or the pipeline. In the natural suction method, the negative pressure generated in the nozzle device due to the ejection of the water jet is used, but the generated negative pressure is limited and difficult to increase. Therefore, there is a problem that the distance between the abrasive storage tank that can stably supply the abrasive and the nozzle device becomes short.

  The first problem will be described with reference to FIG. FIG. 7 shows the configuration of a general pumping system, wherein 1 is a nozzle device, 2 is an ultra-high pressure water pump, 3 is an abrasive storage tank, 6, 13 and 15 are valves, and 7 is an abrasive supply. A path, 8 is a compressed air supply source, and 14 is a compressed air supply path. The abrasive in the storage tank 3 is supplied to the nozzle device 1 through the abrasive supply path 7 together with the compressed air from the compressed air supply source 8, and is injected together with the water jet.

  The main factors that determine the abrasive supply amount are the supply amount of compressed air, the diameter of the lower outlet of the storage tank 3, and the inner diameter and length of the abrasive supply path 7. Therefore, in order to adjust the abrasive supply amount to a desired amount, it is necessary to appropriately set the supply amount of compressed air in accordance with other factors, but the apparatus configuration in FIG. 7 does not have such a function. . Therefore, it is difficult to stably supply the abrasive in a desired amount with the apparatus configuration of FIG.

  The second problem will be described with reference to FIG. FIG. 8 shows a configuration of a general natural suction system, wherein 1 is a nozzle device, 2 is an ultra-high pressure water pump, 3 is an abrasive storage tank, 6, 13 and 15 are valves, and 7 is an abrasive. A supply path, 8 is a compressed air supply source, and 14 is a compressed air supply path. The abrasive in the storage tank 3 is supplied to the nozzle device 1 through the abrasive supply path 7 by the negative pressure generated in the nozzle device 1 and is injected together with the water jet. Therefore, when the length of the abrasive supply path 7 is increased, the suction ability of the abrasive is weakened, the amount of the abrasive supply is decreased, or the supply amount cannot be kept constant. Therefore, the length of the pipeline of the abrasive supply path 7 that can stably supply the abrasive becomes short.

  In general, the abrasive water jet cutting method cuts the workpiece by the abrasive grinding ability mixed with the water jet ejected from the nozzle device, and the quality of the cutting depends on the stable supply of the abrasive and the mixing. It is understood as a thing.

  Therefore, an object of the present invention is to provide an abrasive supply method that is stable over a long distance and can easily adjust the abrasive supply amount to a desired amount in accordance with cutting conditions, with respect to the problems of the conventional abrasive supply method. Is to provide an abrasive water jet cutting method and apparatus with good performance.

  A basic requirement for an apparatus for achieving the object of the present invention is that a nozzle apparatus having a mixing region for mixing abrasive particles with a liquid pressurized by a pump, and polishing for supplying abrasive particles in a storage tank to the nozzle apparatus. In an apparatus for generating an abrasive water jet comprising a supply flow path for conductive particles and a supply flow path for compressed air connected to join the supply path for the abrasive particles, at least one of the supply flow paths A variable-type throttle that adjusts the throttle amount of the flow path area of the portion is provided in a portion upstream of the merge position.

  The basic requirement of the method is that the abrasive particle supply path and the compressed air supply path to the nozzle apparatus are merged, and the flow after the merge is supplied into the nozzle apparatus, and the nozzle apparatus In the method of generating abrasive water jets by mixing abrasive particles with an inner water jet, at least one of the flow rate of compressed air or the supply amount of abrasive particles upstream of the merged position The amount of abrasive particles in the abrasive water jet is adjusted by adjusting the amount.

  According to the present invention, since the amount of the abrasive in the abrasive water jet can be adjusted, it is possible to provide an abrasive water jet cutting method and apparatus with good performance.

  Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings, but the present invention is not limited to this embodiment. FIG. 1 is a system diagram of an abrasive water jet cutting apparatus according to a first embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a nozzle device. The nozzle device 1 includes a water nozzle inside the nozzle device 1 that generates a water jet by restricting the flow of supplied ultrahigh pressure water, and a mixing region through which the water jet passes, and has passed through the mixing region. A mixing nozzle for discharging (also referred to as jetting) a water jet as an abrasive water jet is provided at the tip.

  The nozzle device 1 is connected to an abrasive supply system, an ultra-high pressure water supply system, and a compressed air supply system. The ultra high pressure water supply system sucks water from a water source as a liquid and boosts the pressure to an ultra high pressure defined as 100 MPa or more (in this embodiment, the pressure is increased to about 390 MPa by the ultra high pressure water pump 2). A high-pressure hose connected between the ultra-high pressure water pump 2 and the nozzle device 1 so that the water pressurized by the ultra-high pressure water pump 2 passes through the water nozzle in the nozzle device 1, and the middle of the high-pressure hose. And a valve 15 that opens and shuts off water in the high-pressure hose. In this manner, the nozzle device is equipped with a water supply path from the ultrahigh pressure water pump 2 to the nozzle device 1 via the valve 15.

  The abrasive supply system includes an abrasive storage tank 3, an abrasive supply path 7 connected to the nozzle device 1 so that one end is connected to the abrasive storage tank 3 and the other end communicates with the mixing region of the nozzle device 1. The valve 6 and the abrasive throttle device 4 are provided in series with each other in the abrasive supply path. A resin hose is used as the abrasive supply path 7. In addition, the variable aperture device 4 employs a variable aperture device having a variable aperture amount. The abrasive throttle device 4 can partially narrow the flow area of the resin hose constituting the abrasive supply path 7 to narrow it, or conversely loosen the throttle to widen it, and can adjust the flow rate of the flow path.

  The compressed air supply system is a compressed air supply source 8 such as an air compressor and two systems of compressed air in which one end is connected to the common compressed air supply source 8 and the other end is connected in the middle of the abrasive supply path 7. Supply paths 12 and 14 are provided. The connection position of the compressed air supply paths 12, 14 to the abrasive supply path 7 is a portion closer to the nozzle device 1 than the valve 6 or the abrasive throttle device 4 of the abrasive supply path 7, and the connection position thereof is the same as that of the abrasive supply path 7. It becomes a joining position with the compressed air supply paths 12 and 14. In the abrasive supply path 7, the abrasive storage tank 3 side is the upstream side and the nozzle device 1 side is the downstream side. Therefore, the valve 6 and the abrasive throttle device 4 of the abrasive supply path 7 are arranged upstream of the merging position. Will be.

  By connecting the resin hose to the compressed air supply source 8 and the abrasive supply path 7 in both the compressed air supply paths 12 and 14, the air flow paths of the compressed air supply paths 12 and 14 are configured. The resin hose of the compressed air supply path 12 is a valve that opens and shuts off the air flow from the upstream side when the compressed air supply source 8 side is the upstream side and the opposite side is the downstream side. 9, a flow meter 10 for measuring the flow rate of air, and a compressed air throttle device 11 are sequentially provided in series. The compressed air throttle device 11 can partially narrow the flow area of the resin hose constituting the compressed air supply path 12 to narrow it, or conversely loosen the throttle to widen it, and adjust the flow rate of the flow path. it can. The resin hose of the other compressed air supply path 14 is equipped with a valve 13 that opens and closes the air flow in the air flow path.

  The abrasive storage tank 3 is received by a load cell 5 which is a mass meter, and the total load of the abrasive storage tank 3 and the abrasive stored therein can be measured by the load cell 5. The load cell 5 is a mass meter of a type that uses a piezoelectric element as a sensor that converts the magnitude of pressure due to a load into a magnitude of voltage and outputs a measurement result of mass as an electrical signal.

  An amplifier 16 with a display is connected to the load cell 5 through a signal line 17, and an electrical signal representing a result measured by the load cell 5 is transmitted to the amplifier 16 with a display through the signal line 17. The electric signal is amplified by the display-equipped amplifier 16 and the display device attached to the display-equipped amplifier 16 performs processing for expressing the mass corresponding to the electric signal by display contents such as numbers that can be seen by humans. It has come to be done in.

  In the apparatus for generating an abrasive water jet having such a configuration, before starting the cutting operation with the abrasive water jet, the generator for generating the abrasive water jet is set in a normal stop state in which the generation of the abrasive water jet is not performed. In the normal stop state, the valves 6, 9 and 15 are closed and only the valve 13 is opened. In this state, compressed air from the compressed air supply source 8 is supplied to the mixing region of the nozzle device 1 through the compressed air supply path 14 to the mixing region of the nozzle device 1, and the compressed air that has passed through the mixing region passes from the tip of the nozzle device into the mixing region. Exhausted outside with moisture.

  By such a normal stop state, the mixing area in the nozzle device 1 is kept dry to prevent wetting. When starting cutting with an abrasive water jet, the valve 15 is opened, the ultra high pressure water pump 2 is activated, and the water sucked from the water source is boosted by the ultra high pressure water pump 2 and passed through the water nozzle in the nozzle device 1. A water jet is generated, and the water jet is ejected from the nozzle device 1.

  Thereafter, the valve 9 is opened to supply the compressed air from the compressed air supply source 8 to the mixing region in the nozzle device 1 and the valve 13 is closed. Next, the valve 6 is opened and stored in advance in the abrasive storage tank 3. The previously-prepared abrasive is fed from the abrasive storage tank 3 to the merging position of the compressed air supply path 12 and the abrasive supply path via the abrasive throttle device 4. Then, the abrasive is accompanied by the compressed air, passes through the abrasive supply path 7, and is fed into the mixing area in the nozzle device 1 together with the compressed air, and is mixed with the water jet in the mixing area to generate an abrasive water jet. The abrasive water jet including the abrasive is jetted from the mixing nozzle at the tip of the nozzle device 1 toward the object to be cut.

  The abrasive that collides with the cutting object along with the abrasive water jet cuts the cutting object and finally cuts the cutting object.

  Here, in adjusting the abrasive supply amount, first, the abrasive expansion device 4 is adjusted to an opening degree corresponding to a desired abrasive supply amount. Here, the desired abrasive supply amount is a supply amount suitable for cutting, which is determined from the material and plate thickness of the object to be cut.

  Then, while supplying the abrasive from the abrasive storage tank 3 to the mixing region in the nozzle device 1 through the abrasive squeezing device 4, the abrasive supply amount is determined from the temporal change in the total mass of the abrasive obtained from the load cell 5 and the abrasive storage tank 3. Calculate and compare with the desired abrasive supply. The temporal change in the total mass is calculated based on the result of mass measurement by the load cell 5 at intervals.

  Between the abrasive supply amount to the nozzle device 1 and the compressed air supply amount, there is a relationship that when the opening degree of the abrasive throttle device 4 is the same, the abrasive supply amount decreases with an increase in the compressed air supply amount. When the current abrasive supply amount is smaller than the desired abrasive supply amount, the opening degree of the compressed air throttle device 11 is reduced, and vice versa, the opening degree of the compressed air throttle device 11 is increased. The abrasive supply amount is adjusted so that the difference from the desired abrasive supply amount is within the target set value.

  The reason why such a relationship between the compressed air supply amount and the abrasive supply amount is established is that when the compressed air supply amount increases, the pressure at the merging position of the compressed air supply route and the abrasive supply route increases, and the pressure from the abrasive storage tank increases. Since the supply of the abrasive to the merging position is hindered, it is considered that the amount of the abrasive supply decreases. On the other hand, when the amount of compressed air supply decreases, the pressure at the merging position drops and the abrasive storage tank moves to the merging position. Since the hindrance to the supply of the abrasive is alleviated, the amount of the abrasive supply is considered to increase.

  As described above, since the present embodiment includes the abrasive throttle device 4, the load cell 5, and the compressed air throttle device 11, in order to adjust the abrasive supply amount to a desired amount, first, the abrasive throttle device 4 is desired. The opening degree is adjusted in accordance with the amount of abrasive supply, and thereafter, the time change of the mass measurement value of the load cell 5 is recognized from the time change of the mass displayed on the display-equipped amplifier 16, and the time change of the mass is determined. By comparing the obtained abrasive supply amount with the desired abrasive supply amount and finely adjusting the abrasive supply amount by changing the compressed air supply amount by adjusting the opening of the compressed air throttling device 11 as required, the desired abrasive supply amount can be obtained. It becomes possible to supply stably into the mixing region in the nozzle device 1 with the abrasive supply amount. The compressed air supply amount is confirmed by measuring the flow rate of the compressed air in the compressed air supply path 12 with the flow meter 10.

  Therefore, by setting the abrasive supply amount optimally for the object to be cut, precise cutting can be performed, or since the abrasive supply amount is stable, there is no need to consume additional abrasives. Can be kept to the minimum necessary.

  Furthermore, the abrasive can be stably supplied in a constant amount by appropriately monitoring the amount of the abrasive supplied and adjusting the compressed air throttle device 11 as necessary.

  It is obvious that an equivalent function can be obtained by calculating the compressed air supply amount from the pressure difference between any two points in the compressed air supply path 12 instead of the flow meter 10. In addition, the time change of the amount of supply of the abrasive is replaced with the result of the mass measurement of the load cell 5, and the time change of the volume of storage of the abrasive in the abrasive storage tank 3 is measured with a level meter to change the amount of time of the supply of the abrasive You may grasp as.

  Furthermore, when adjusting the amount of supply of the abrasive, instead of adjusting the opening of the compressed air throttle device 11, the opening of the abrasive throttle device 4 may be adjusted.

  FIG. 2 is a system diagram of an abrasive water jet cutting device according to a second embodiment of the present invention. This embodiment is intended to be tailored to automatically adjust the abrasive supply amount to a desired abrasive supply amount.

  In FIG. 2, an electric signal representing a measurement result of the load cell 5 that measures the total mass of the abrasive storage tank 3 and the abrasive in the moment is input to the electronic control device 32 via the signal line 33 every moment. And the electronic control unit 32 are electrically connected by a signal line 33.

  A mass flow controller 31 is provided in the compressed air supply path 12 as a throttle device that adjusts the flow rate of the compressed air in the compressed air supply path 12. The mass flow controller 31 and the electronic control device 32 are electrically connected by a signal line 34. The mass flow controller 31 is configured to receive a control signal from the electronic control device 32 through the signal line 34 and adjust the flow rate of the compressed air in the compressed air supply path 12 based on the control signal.

  Since other configurations are the same as those of the first embodiment, the same components are denoted by the same reference numerals as those of the first embodiment, and description thereof is omitted.

  When the electronic control device 32 receives a signal representing the mass measured from the load cell 5 through the signal line 33, the electronic control device 32 changes the time-dependent change in the mass of the abrasive in the abrasive storage tank 3 based on the signal received from the load cell 5. The abrasive supply is calculated from the change over time. Further, a control signal is sent from the electronic control device 32 to the mass flow controller 31 via the signal line 34 so that the abrasive supply amount becomes a desired abrasive supply amount.

  As described above, the mass flow controller 31 is provided with a mechanism (not shown) that automatically adjusts the flow rate of the compressed air by an external control signal. As a result, it is possible to save the labor of adjusting the abrasive supply amount manually.

  FIG. 3 shows a signal input / output system configuration of the electronic control unit 32 of the second embodiment. In FIG. 3, the load cell 5 is connected to the amplifier 41 as a signal representing the mass measured by converting the magnitude of strain corresponding to the total mass of the abrasive storage tank 3 and the abrasive remaining in the tank into a voltage by a bridge circuit. Output.

The output voltage from the load cell 5 is input to the amplifier 41, amplified by the amplifier 41 and input to the A / D converter 42, and the signal representing the mass measured here is converted into a digital value and input to the input port 43. Entered. The signal of the digital value sent to the input port 43 is taken into the personal computer 44 and processed in detail later with reference to FIG. 4 so that the abrasive supply amount becomes the desired abrasive supply amount. Is output to the output port 45. The control signal is converted into an analog value control signal by the D / A converter 46 and output to the mass flow controller 31.

  The stop signal generated by the abrasive supply stop button 47 is digitized by the A / D converter 42 and stored in the memory of the personal computer 44 via the input port 43. The abrasive supply stop button 47 is visually confirmed by the worker that the cutting operation has been completed, and is pushed by the worker when the cutting operation is completed, and a stop signal is generated.

  FIG. 4 shows a flow chart for adjusting the abrasive supply amount within a target set value with respect to the desired abrasive supply amount as an example of feedback control for automatically adjusting the above-mentioned abrasive supply amount. It is. Based on each step shown in this flowchart, the electronic control device 32 executes a control signal generation process for controlling the mass flow controller 31.

  In step 61 in FIG. 4, it is determined whether or not a stop signal is generated by pressing the abrasive supply stop button 47 based on whether or not the stop signal is stored in the memory of the personal computer 44. This determination means whether or not to stop the supply of the abrasive (for example, the supply of the abrasive is stopped when the cutting is finished). Naturally, when the stop signal is stored in the memory of the personal computer 44, it is determined that the supply of the abrasive is stopped, and the processing flow in the electronic control unit 32 is ended. In this case, after the operator pushes the abrasive supply stop button 47, the valve 6 in the abrasive supply path 7 is closed to stop the supply of the abrasive, and the valve 9 and the valve 15 are also closed and the valve 13 is opened. As a result, the compressed air is passed through the compressed air supply path 14 into the mixing region in the nozzle device 1 to be dried, and the valve 13 is also closed later.

  When it is determined in step 61 in FIG. 4 that the stop signal is not stored in the memory of the personal computer 44, it is determined that the supply of the abrasive is not stopped, and in that case, the process proceeds to step 62. .

  In step 62, the measured value of the load cell 5 is inputted a plurality of times at regular time intervals, and the amount of abrasive supply per unit time is calculated by the least square method based on the inputted data. In this way, the current abrasive supply amount is obtained. Next, in step 63, whether or not the current abrasive supply amount is within the target set value with respect to the desired abrasive supply amount, the difference between the current abrasive supply amount and the desired abrasive supply amount is the target set value ( For example, if it is within the target set value, the process returns to step 61, the current abrasive supply state is maintained, and if not, the abrasive supply after step 64 is performed. Move on to the volume adjustment process.

In step 64, it is determined whether the current abrasive supply amount is larger or smaller than the desired supply amount. If it is determined in step 64 that the number is large, the process proceeds to step 65, and the personal computer 44 generates a signal for increasing the amount of compressed air supplied by the compressed air supply path 12 in step 65 in order to reduce the current amount of abrasive supply. And output to the mass flow controller 31. When the mass flow controller 31 receives a signal for increasing the amount of compressed air supplied from the electronic control unit 32, the mass flow controller 31 functions in a direction to increase the flow rate of the compressed air in the compressed air supply path 12, and the compression increases with the increase. The amount of abrasive sent to the nozzle device 1 side by air decreases.

  On the other hand, if it is determined in step 64 that the amount is small, the process proceeds to step 66 where the personal computer 44 generates a signal for decreasing the compressed air supply amount and outputs it to the mass flow controller 31 in order to increase the abrasive supply amount. . When the mass flow controller 31 receives a signal for reducing the compressed air supply amount from the electronic control device 32, the mass flow controller 31 functions in a direction to decrease the flow rate of the compressed air in the compressed air supply path 12, and the compression is accompanied by the decrease. The amount of abrasive that is sent to the nozzle device 1 side by air increases.

  In this way, the amount of abrasive supply to the nozzle device 1 is automatically adjusted to be adjusted so that the desired amount of abrasive supply falls within the target set value.

  After performing Step 65 or Step 66, the process returns to Step 61. Such a process is repeated until it is determined in step 61 that the abrasive supply stop button is pressed and a stop signal is generated and the supply of the abrasive is stopped in step 61.

  As in the third embodiment shown in FIG. 5, it is connected to the electronic control unit 32 so that the opening degree of the abrasive throttle device 4 can be controlled, and the opening of the abrasive throttle device 4 is performed in the same procedure as in the second embodiment. Even if the degree is automatically adjusted by the control signal from the electronic control unit 32, it is obvious that the same effect as the second embodiment can be obtained.

  FIG. 6 shows an abrasive supply path 7 in the abrasive water jet cutting apparatus according to the fourth embodiment of the present invention. In FIG. 6, the abrasive storage tank 3 is equipped with a plurality of abrasive outlets. Abrasive supply paths 7a, 7b,... 7n are provided through valves 82a, 82b,... 82n and abrasive throttle devices 81a, 81b,. The abrasive supply paths 7 a, 7 b,... 7 n are arranged in parallel with each other, joined to the compressed air supply path 12, and connected to the abrasive supply path 7. Other configurations are the same as those of the first embodiment. .., 81n are throttle devices having different opening degrees.

In the first embodiment, there is one abrasive diaphragm device 4 corresponding to the abrasive diaphragm devices 81a, 81b,... 81n, and a predetermined opening degree adjustment has to be appropriately performed. However, in the fourth embodiment, there are abrasive aperture devices 81a, 81b,... 81n having a plurality of different apertures, and the aperture according to a desired abrasive supply amount from among the abrasive aperture devices 81a, 81b,. By selecting any one of the abrasive supply paths 7a, 7b,..., 7n equipped with the above-described abrasive throttle device, and opening a valve in the selected abrasive supply path and closing a valve in the other abrasive supply path. The amount of supply to the nozzle device 1 can be easily set by the opening degree of the abrasive throttle device in the abrasive supply path. Further, the supply amount of the abrasive to the nozzle device 1 can be easily changed by changing the selection of the abrasive supply paths 7a, 7b,. Other matters are the same as those in the first embodiment.

  In any of the above-described embodiments, the amount of the abrasive supply to the nozzle device 1 can be finely adjusted by adjusting the opening of the compressed air throttle device 11, so that the amount of the abrasive supply to the nozzle device 1 is desired. Therefore, it is possible to stably supply to the above-mentioned abrasive supply amount, and therefore it is possible to obtain the effect of improving the cutting performance of the abrasive water jet cutting apparatus.

  The present invention has application in an abrasive water jet cutting device.

1 is a system diagram of an abrasive water jet cutting device according to a first embodiment of the present invention. It is a systematic diagram of the abrasive water jet cutting device by the 2nd example of the present invention. FIG. 3 is a signal input / output system diagram of the electronic control device in FIG. 2. FIG. 3 is a flowchart of feedback control processing by a computer constituting the electronic control device in FIG. 2. It is a systematic diagram of the abrasive water jet cutting device by 3rd Example of this invention. It is a principal part fragmentary diagram of the abrasive supply path | route of the abrasive water jet cutting device by 4th Example of this invention. It is a systematic diagram of the abrasive water jet cutting device which the inventor assumed. It is a systematic diagram of the other abrasive water jet cutting device which the inventor assumed.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Nozzle apparatus, 2 ... Super high pressure water pump, 3 ... Abrasive storage tank 4, 81a, 81b, 81n ... Abrasive throttle apparatus, 5 ... Load cell, 6, 9, 13, 15, 82, 82a, 82b, 82n ... Valves 7, 7a, 7b, 7n ... Abrasive supply path, 8 ... Compressed air supply source, 10 ... Flow meter, 11 ... Compressed air throttle device, 12, 14 ... Compressed air supply path, 16 ... Amplifier with display, 17, 33, 34 ... signal lines, 32 ... electronic control unit.

Claims (10)

The abrasive particle supply path and the compressed air supply path to the nozzle device are merged, and the flow after the merge is supplied into the nozzle device,
In the method of generating an abrasive water jet by mixing the abrasive particles with the water jet in the nozzle device,
A method of generating an abrasive water jet that adjusts at least one of the flow rate of the compressed air or the supply amount of the abrasive particles upstream of the position of the merge.   In Claim 1, the supply amount of the abrasive particles is determined, and depending on the difference between the determined supply amount of the abrasive particles and the predetermined supply amount of the abrasive particles, the flow rate of the compressed air or the A method of generating an abrasive water jet that adjusts at least one of the supply amount of abrasive particles.   In Claim 2, when the supply amount of the determined abrasive particles is larger than the predetermined supply amount of the abrasive particles, the flow rate of the compressed air is increased or the supply amount of the abrasive particles is increased. A method of generating an abrasive water jet that performs the adjustment adjustment by decreasing the flow rate of the compressed air or increasing the supply amount of the abrasive particles.   The flow rate adjusting means installed in the supply path of abrasive particles and the supply path of compressed air upstream from the position of the merging position according to claim 3, the determined supply amount of the abrasive particles and the predetermined polishing amount. A method for generating an abrasive water jet that performs the above-described adjustment by adding feedback control according to the difference from the supply amount of the active particles.   5. The abrasive particle according to claim 1, wherein the adjustment of the supply amount of the abrasive particles passes through the abrasive particles through a diaphragm selected from a plurality of diaphragms having different diaphragm amounts. 6. And generating an abrasive water jet by causing the abrasive particles to reach the position of the merge.   6. The abrasive storage tank according to claim 1, wherein the abrasive particles are stored in an abrasive storage tank, the abrasive particles in the abrasive storage tank are supplied to a supply path of the abrasive particles, and the abrasive storage tank. A method of generating an abrasive water jet that measures the amount of the abrasive particles in the inside and determines the supply amount of the abrasive particles based on the measurement result.   The total mass of the abrasive storage tank and the abrasive particles in the abrasive storage tank according to claim 6 is measured a plurality of times with a lapse of a supply time of the abrasive particles with a mass meter, A method of generating an abrasive water jet for determining the supply amount of the abrasive particles per fixed time from the result. A nozzle device having a mixing region for mixing abrasive particles with a liquid pressurized by a pump, an abrasive particle supply channel for supplying abrasive particles in a storage tank to the nozzle device, and an abrasive particle supply path In an apparatus for generating an abrasive water jet comprising a compressed air supply passage connected so as to merge with
The apparatus which produces | generates an abrasive water jet provided with the variable type | mold throttle apparatus which adjusts the amount of restriction | limiting of the flow-path area of the said part in the part upstream from the position of the said confluence | merging of each said supply flow path.   The supply amount of the abrasive particles according to claim 8, wherein the supply amount of the abrasive particles is in accordance with the difference between the supply amount of the abrasive particles and the supply amount of the abrasive particles determined in advance. If the amount is large, the amount of squeezing of the variable type squeezing device provided in the abrasive particle supply channel is increased, or the amount of squeezing of the variable type squeezing device provided in the compressed air supply channel is decreased. When the amount is small, the amount of squeezing of the variable type throttle device provided in the abrasive particle supply flow path is reduced or the amount of squeezing of the variable type throttle device provided in the compressed air supply flow path is increased. Thus, the apparatus which produces | generates an abrasive water jet provided with the control apparatus which varies the aperture amount of the said variable type aperture device. 10. The mass meter according to claim 9, wherein a mass meter that measures a total mass of the storage tank and the abrasive particles in the storage tank, and a mass measurement is performed a plurality of times as the abrasive particles are supplied with the mass meter. An apparatus for generating an abrasive water jet comprising means for determining the supply amount of the abrasive particles per fixed time from the result.

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