JP2006082188A - Electric discharge machining system and equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric discharge machining system capable of performing electric discharge machining with an excellent positioning repeatability in application to a machining object positioned in a narrow part. <P>SOLUTION: A machining head part 12 is provided with a frame 21 slidably disposed by a elevating cylinder 23 in a case 20 having an opening at the front face, and an oscillating cylinder 25 for oscillating (swing motion) an electrode 22 for the electric machining on the frame 21. The electrode 22 can be reciprocated in the arrow A direction with the frame 21 by the elevating cylinder 23, and reciprocated in the arrow C direction through a link 24 by the oscillating cylinder 25. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electric discharge machining system, and more particularly to an electric discharge machining system suitable for repairing a narrow part such as a reactor internal structure in a nuclear power plant.

  In the event that cracks occur in a reactor internal structure such as a shroud in a nuclear power plant, in order to prevent radiation exposure, the repair equipment must be removed from the water surface while the furnace is still filled with pure water. For example, the work of submerging to a depth of 20 m or more and repairing the cracked part by remote control is required.

Here, various machining techniques are applied to the repair at this time, and one type is electrical discharge machining. In this case, an underwater electrical discharge machining actuator is suspended in a full reactor and the workpiece is processed. A technique has been proposed in which a discharge is generated between a workpiece by applying a voltage while moving the machining electrode up and down, and the damaged portion is cut and removed by the heat (e.g., a patent document). 1).
JP 9-38831 A

  The prior art does not consider the electrode moving mechanism, and has a problem in miniaturization and position reproducibility.

  In the case of the above prior art, since the vertical movement of the electrode is realized by a combination of a stepping motor provided in the actuator and a ball screw, there is a limit to downsizing, and it is possible to process a narrow portion where a sufficient work space cannot be secured. Is unsuitable.

  In addition, in the case of the prior art, it is necessary to move the actuator itself in order to change the machining location, and there is a problem that the position reproducibility is lacking.

  The present invention has been devised in order to solve the above-mentioned problems of the prior art, and its purpose is to apply electric discharge machining to a machining object located in a narrow portion so that electric discharge machining can be performed with good position reproducibility. To provide a system.

  In order to achieve the above object, first, in the invention of claim 1, a machining head portion submerged in a liquid filled in a machining target is used, and electric discharge machining is performed by a machining electrode provided in the machining head portion. In the electric discharge machining system, a fluid pressure operating cylinder that operates with either the same fluid as the liquid or air, and a fluid pressure supply source that supplies the pressure medium to the fluid operating cylinder are used. The fluid pressure operating cylinder is provided in the processing head portion, the pressurized fluid is supplied to the fluid pressure operating cylinder from the fluid pressure supply source installed outside the liquid filled in the processing object, and the fluid The operation of the electrode for electric discharge machining is controlled by a pressure operating cylinder.

  At this time, according to the invention of claim 2, the fluid pressure actuated cylinder includes: an oscillating cylinder for moving the machining electrode in a direction substantially perpendicular to the machining surface to be machined; and the machining electrode. Two types of elevating cylinders that move in a direction substantially parallel to the machining surface to be machined, wherein the fluid pressure supply source supplies the pressure medium to the rocking cylinder; Two types of second pressure units for supplying the pressure medium to the elevating cylinder are used to achieve the above object.

  In this case, according to the invention of claim 3, a third pressure unit is provided for supplying a pressure medium to the pistons of the swing cylinder and the lift cylinder, and the swing cylinder and the lift cylinder are provided by the pressure medium. The piston is biased in the return direction so that the above object can be achieved.

  Further, according to the invention of claim 4, the third pressure unit includes at least an air pressure generating means and an air hydraulic pressure converting means for converting air pressure to hydraulic pressure. Has been able to achieve.

  Next, in order to achieve the above object as well, according to the invention of claim 5, an electrode for electric discharge machining and a surface of the workpiece to be machined are provided in a case having an opening in contact with the surface of the workpiece. A rocking cylinder for rocking with respect to the machining head, a machining head portion that houses a lifting cylinder for moving the electrode parallel to the surface of the workpiece, and a pair of pipes connected to the lifting cylinder The first nozzle / flapper type servo valve that alternately supplies pressure medium from forward and reverse directions and reciprocally moves the piston and the swing cylinder alternately from forward and reverse directions via a pair of pipes. The above-mentioned object can be achieved by providing a second nozzle / flapper type servo valve for supplying a pressure medium to the piston and reciprocating the piston.

  At this time, according to a sixth aspect of the present invention, the first nozzle / flapper type servo valve includes a first valve chamber to which a pressure medium supply pipe is connected and a second valve to which a pressure medium discharge pipe is connected. A chamber, one end opened in the first valve chamber and the other end connected to one end of the lift cylinder via a first pipe, one end opened in the first valve chamber and the other end A second nozzle connected to the other end of the lifting cylinder via two pipes, one end opened in the second valve chamber, and the other end connected to the other end of the lifting cylinder via the second pipe A third nozzle, a fourth nozzle having one end opened in the second valve chamber and the other end connected to one end of the elevating cylinder via the first pipe, the first nozzle in the first valve chamber, First flappers that alternately close the second nozzles and the third flap chamber in the second valve chamber. A second flapper for alternately closing the slip and the fourth nozzle, and a first motor for driving the first flapper and the second flapper, wherein the second nozzle / flapper type servo valve is a pressure medium supply pipe. Is connected to the third valve chamber, the pressure valve discharge pipe is connected to the fourth valve chamber, one end is opened in the third valve chamber, and the other end is connected to the one end of the swing cylinder via the third pipe. A fifth nozzle connected to the other end, a sixth nozzle having one end opened in the third valve chamber and the other end connected to the other end of the swing cylinder via a fourth pipe, and one end connected to the fourth valve. A seventh nozzle that opens into the chamber and has the other end connected to the other end of the oscillating cylinder through the fourth pipe; and one end that opens into the fourth valve chamber and the other end through the third pipe. An eighth nozzle connected to one end of the oscillating cylinder; and the fifth nozzle in the third valve chamber. A third flapper for alternately closing the slip and the sixth nozzle, a fourth flapper for alternately closing the seventh nozzle and the eighth nozzle in the fourth valve chamber, and the third flapper and the fourth flapper. A second motor to be driven is provided so that the above object can be achieved.

  Further, at this time, according to the invention of claim 7, a seal member disposed on the end face of the opening of the case, a suction member for fixing the case to the surface of the processing target, and the case on the processing target side A fluid pressurizing means for supplying a pressure medium for urging the pressure medium, and an injection port for discharging the pressure medium in a direction opposite to the object to be processed. ing.

  Similarly, at this time, according to the invention of claim 8, a drain port for discharging the fluid filled in the case to the outside, a water supply port for supplying new water into the case, A pump that sucks water in the case through a water pipe connected to the drain port, and a water source that supplies water into the case through the water pipe connected to the water supply port are provided. Thus, the above object can be achieved.

  Similarly, at this time, according to the invention of claim 9, the processing head unit has a depth sensor for detecting a processing depth by the electrode, and that the processing depth has reached a set value from the depth sensor. When the signal shown is output, a control means for driving the lifting cylinder to move the machining position is provided so that the above object can be achieved.

  At this time, according to the invention of claim 10, the above-mentioned object can be achieved by suspending the processing head portion and providing a transfer means for transporting the processing head portion to the vicinity of the processing target. ing.

  In the electric discharge machining system using the above means, a swing servo cylinder installed outside the machining head is driven by a servo motor, and the swing cylinder built in the machining head is operated by driving the swing servo cylinder. Since the reciprocating swing of the processing electrode is realized, it is not necessary to house a motor and a ball screw for reciprocating the electrode in the processing head as in the prior art.

  In this way, the present invention combines servo control by a servo motor and control of a pressure medium by a master / slave cylinder system, thereby making it possible to reduce the size and thickness of the processing head and to process in a narrower place. It is characterized by enabling electric discharge machining on the object.

  In addition, the present invention enables the machining electrode to be moved in the case while the machining head is fixed to the machining target by driving an elevating servo cylinder installed outside, so that the machining position can be changed without impairing the position reproducibility. It is possible to move and process a relatively wide area at a time. At this time, examples of the pressure medium include water, oil, and air.

  Furthermore, the present invention is characterized by including a third pressure unit that supplies a pressure medium for urging each piston in the return direction to the swing cylinder and the lift cylinder.

  As a result, it is possible to always apply back pressure to the oscillating cylinder and the lifting cylinder, and the responsiveness of the machining head side oscillating and lifting cylinder when the oscillating servo cylinder and the lifting servo cylinder operate in the return direction. Can be improved.

  Further, according to the present invention, the third pressure unit is further provided with an air pressure generating means and an air hydraulic pressure converting means for converting air pressure into a hydraulic pressure.

  Furthermore, in the present invention, an electrode for electric discharge machining, a swing cylinder for swinging the electrode with respect to the processing target, and the electrode to be processed in a case having an opening in contact with the surface of the processing target. On the other hand, a processing head in which an elevating cylinder for moving in parallel is housed, and a pressure medium is alternately supplied to the elevating cylinder through a pair of pipes in two directions, and the piston is reciprocated. 1 nozzle / flapper type servo valve and a second nozzle / flapper type servo valve that alternately supplies pressure medium to the rocking cylinder through a pair of pipes in both forward and reverse directions and reciprocates the piston. It is characterized by that.

  In the case of this electric discharge machining system as well, the second nozzle / flapper type servo valve installed outside is operated to operate the rocking cylinder in the machining head, and the reciprocating rocking of the machining electrode is realized. There is no need to house a motor or ball screw for reciprocating the electrodes in the machining head as in the prior art.

  For this reason, further miniaturization or further thinning of the machining head can be realized, and electric discharge machining can be performed on a machining target located in a narrower place.

  Also, by driving the first nozzle / flapper type servo valve installed outside, the machining electrode can be moved within the case while the machining head is fixed to the machining target, so that the machining location can be maintained without sacrificing position reproducibility. Can be changed, and a relatively wide range can be processed at a time. Here, as the pressure medium, for example, water, oil, and air are applicable.

  According to the present invention, the first nozzle / flapper servo valve further includes a first valve chamber to which a pressure medium supply pipe is connected, a second valve chamber to which a pressure medium discharge pipe is connected, One end is opened in the first valve chamber, the other end is connected to one end of the elevating cylinder via a first pipe, one end is opened in the first valve chamber, and the other end is second. A second nozzle connected to the other end of the elevating cylinder via a pipe, one end opened in the second valve chamber, and the other end connected to the other end of the elevating cylinder via the second pipe A third nozzle, a fourth nozzle having one end opened in the second valve chamber and the other end connected to one end of the elevating cylinder via the first pipe, a first nozzle in the first valve chamber, A first flapper that alternately closes the second nozzle; a third nozzle in the second valve chamber; and A second flapper that alternately closes four nozzles; and a first motor that drives the first flapper and the second flapper; and the second nozzle / flapper servo valve is connected to a pressure medium supply pipe. A third valve chamber, a fourth valve chamber connected to a pressure medium discharge pipe, one end opened into the third valve chamber, and the other end connected to one end of the swing cylinder via a third pipe; A fifth nozzle, one end opened in the third valve chamber, the other end connected to the other end of the oscillating cylinder via a fourth pipe, and one end opened in the fourth valve chamber A seventh nozzle having the other end connected to the other end of the swing cylinder via the fourth pipe, one end opening into the fourth valve chamber, and the other end passing through the third pipe. An eighth nozzle connected to one end of the oscillating cylinder; a fifth nozzle and a second nozzle in the third valve chamber; A third flapper that alternately closes the nozzles; a fourth flapper that alternately closes the seventh and eighth nozzles in the fourth valve chamber; and a second motor that drives the third and fourth flappers. It is characterized by having prepared.

  At this time, the remote handling means for further suspending the processing head and disposing it in the vicinity of the processing target, the seal member disposed on the end face of the opening of the case, and fixing the case to the surface of the processing target An adsorbing member, a pressurizing means for supplying a pressure medium (water or air) for urging the case to the processing target side, and an injection port for discharging the pressure medium in a direction opposite to the processing target. It is characterized by having prepared.

  As a result, the processing head can be brought into close contact with the surface of the processing target, and processing waste generated in the case can be prevented from being scattered outside.

  Further, according to the present invention, the case is further provided with a drain port for discharging water filled in the case to the outside, and a water supply port for supplying new water into the case. A pump for sucking water in the case through a water pipe connected to the drain port; and a water source for supplying water into the case through a water pipe connected to the water inlet. It is a feature.

  When carrying out underwater electrical discharge machining in a reactor filled with pure water, a mechanism for circulating the water in the case is provided in this way, and machining waste that adversely affects machining characteristics is forcibly discharged to the outside. Although this is desirable, this is achieved by the present invention.

  Further, according to the present invention, when a depth sensor for detecting a processing depth for a processing object by an electrode and a signal indicating that the processing depth has reached a set value are output from the depth sensor, Control means for moving the machining position to a predetermined position by driving the elevating cylinder is provided.

  As a result, it is possible to automatically process at a preset depth over a relatively wide range.

  According to the present invention, since the repair facility can be further reduced in size or further reduced in thickness, it is possible to perform effective processing on a processing object located in a narrow portion and to swing only the electrode. The machining location can be changed without impairing the position reproducibility.

  Hereinafter, an electric discharge machining system according to the present invention will be described in detail with reference to embodiments shown in the drawings.

  First, the first embodiment of the present invention will be described with reference to FIG. 1. This embodiment is an embodiment in which the electric discharge machining system according to the present invention is applied to the electric discharge machining of a nuclear reactor. The whole is represented by 10, and the object to be processed such as a pressure vessel of a nuclear reactor is represented by 26.

  Therefore, in this case, water (pure water) filled in the pressure vessel becomes an insulating liquid for electric discharge machining, so-called machining liquid.

  The electric discharge machining system 10 is roughly divided into a machining head unit 12 and an external equipment group 13. The machining head unit 12 is suspended by transfer means such as a winding mechanism 11 and filled with pure water. External equipment group 13 installed outside the nuclear reactor after being transported to the vicinity of the site requiring electric discharge machining in the reactor, that is, the structure inside the nuclear reactor, particularly near the surface of the workpiece 26 such as the core shroud. So that the necessary electrical discharge machining can be performed on the necessary part.

  For this reason, the machining head unit 12 includes a case 20 having an opening, a frame 21 slidably disposed in the case 20, an electric discharge machining electrode 22 movably disposed in the frame 21, A lift cylinder 23 for reciprocating the frame 21 in the vertical direction in the figure, and a swing cylinder 25 for swinging (swinging) the electrode 22 with respect to the workpiece 26 via a link 24 of the swing mechanism. It has.

  First, the case 20 is provided with a seal member 27 provided so as to be interposed between the surface of the processing object 26 and the end face of the opening, and a bellows type suction for fixing the case 20 to the surface of the processing object 26. A board 28 is provided.

  Here, in FIG. 1, only one suction disk 28 is drawn for illustration, but actually, a plurality of (at least three) suction disks are provided, each of which includes pressurized water. An injection port 29 for discharging (pressurized water) in a direction opposite to the workpiece 26 is provided.

  Further, the case 20 is provided with a drain port 30 for discharging internal water to the outside and a water supply port 31 for supplying water into the case 20.

  Next, the external equipment group 13 includes the first hydraulic unit 40 and the second hydraulic unit 41, the processing power supply unit 42, the control unit 43, the third hydraulic unit 44, the water tank 45, the first tank, in addition to the winding mechanism 11 described above. The 1 water supply pump 46, the 2nd water supply pump 47, and the filter 48 are provided.

  First, the first hydraulic unit 40 includes a swing servo cylinder 50, a first servo motor 51, and a ball screw 52, and the rotational force of the first servo motor 51 is driven by the ball screw 52 by the swing servo cylinder 50. It is converted into a reciprocating motion of the piston inside.

  The inside of this oscillating servo cylinder 50 is connected to the oscillating cylinder 25 of the machining head portion 12 through a water distribution pipe 53. Therefore, the swing cylinder 25 is operated in the push-out direction in response to the pressing operation of the piston of the swing servo cylinder 50.

  As a result, the swing cylinder 25 can be operated in response to the operation of the first servo motor 51, and therefore it is not necessary to incorporate the first servo motor 51 and the ball screw 52 in the machining head portion 12.

  Next, the second hydraulic unit 41 includes a lift servo cylinder 54, a second servo motor 55, and a ball screw 56, and the rotational force of the second servo motor 55 is moved into the lift servo cylinder 54 by the ball screw 56. It is converted into a reciprocating motion of a certain piston.

  The inside of the lift servo cylinder 54 is connected to the lift cylinder 23 of the processing head unit 12 through a water distribution pipe 57. Therefore, the lifting cylinder 23 is operated in the pushing direction in response to the pressing operation of the lifting servo cylinder 54.

  Accordingly, the elevating cylinder 23 can be operated in response to the operation of the second servo motor 55, and therefore it is not necessary to incorporate the second servo motor 55 and the ball screw 56 in the machining head unit 12.

  Next, the third water pressure unit 44 includes a compressor 58 and an air / water pressure conversion cylinder 59 and functions to convert the air pressure generated by the compressor 58 into water pressure by the air / water pressure conversion cylinder 59.

  The pneumatic / hydraulic pressure conversion cylinder 59 is connected to the swing cylinder 25 and the lift cylinder 23 of the machining head portion 12 via a water distribution pipe 60 (including branch pipes 60a and 60b). The cylinder 23 has a function of constantly applying pressure (back pressure) to the piston in the return direction.

  The first water supply pump 46 is connected to the drain port 30 of the processing head unit 12 and the water tank 45 through the water distribution pipe 61, and functions to suck the water in the case 20 and return it to the water tank 45. At this time, the water distribution pipe 61 is provided with a filter 48 in the middle, and the removal of processing waste and the like can be obtained by the filter medium.

  Therefore, when the first water supply pump 46 is operated, the water in the case 20 is discharged to the outside. As a result, the purified water in the water tank 45 is supplied to the water supply port 31 of the case 20 through the water distribution pipe 62. It flows into the case 20 and is replenished.

  Further, the second water supply pump 47 functions to supply purified water in the water tank 45 to the injection port 29 of the processing head unit 12 through the water distribution pipe 63.

  Next, the processing power supply unit 42 functions to apply a voltage between the electrode 22 and the processing target 26 via the power supply cables 64a and 64b to cause a discharge necessary for processing.

  Here, the control unit 43 includes a microcomputer, various driver circuits, a storage device storing a control program, and the like, and includes a depth sensor 66 and a first origin of the machining head unit 12 via signal cables 65a to 65c. The sensor 67 and the second origin sensor 68 are connected.

  The control unit 43 is connected to the origin sensor 70 and the first servo motor 51 of the first hydraulic unit 40 and the origin sensor 72 and the second servo motor 55 of the second hydraulic unit 41 via signal cables 69a to 69d. ing.

  Next, FIG. 2 is a perspective view of the machining head portion 12, which shows details of a flat case 20 having an open front side and a frame 21 disposed in the case 20. A rectangular parallelepiped machining electrode 22 arranged at the center of the frame 21, a lifting cylinder 23 attached to the upper plate 73 of the case 20, and a swing cylinder 25 attached to the lower frame 74 of the frame 21 are shown. Yes.

  At this time, four flanges 75 project from the left and right sides of the frame 21, and through holes formed in these flanges 75 are inserted into guide rods 76 attached to the inside of the case 20. The upper shaft 78 of the frame 21 is connected to the drive shaft 77 of the elevating cylinder 23 through the upper plate 73 of the case 20.

  As a result, the frame 21 moves up and down as indicated by the straight arrow A along with the electrode 22 and the swing cylinder 25 in response to the reciprocating motion of the elevating cylinder 23.

  Here, the electrode 22 is attached to one surface (upper surface in the figure) of the conductive power feeding plate 79 at the lower end thereof, and the other surface (lower surface in the figure) of the power feeding plate 79. Is attached to the electrode support member 80 via an insulating plate (not shown).

  The lower end portion of the electrode support member 80 is rotatably held on the side surface of the frame 21 via the support shaft 81, and further, the electrode support member 80 is turned from the support shaft 81 to the surface side (the processing object 26 side in FIG. 1). ), One end of the link 24 of the swing mechanism is rotatably connected, and the drive shaft 82 of the swing cylinder 25 passes through the lower frame 74 of the frame 21 at the other end. Similarly, it is rotatably connected.

  As a result, in response to the reciprocating motion of the swing cylinder 25 indicated by the straight arrow B, the swing (swing) motion of the electrode 20 indicated by the arc-shaped arrow C is obtained.

  The upper plate 73 of the case 20 is provided with a plus-side power supply connection portion 83 and a minus-side power supply connection portion 84, which are connected to the processing power supply portion 42 (FIG. 1) via power supply cables 64a and 64b, respectively. .

  Both ends of the power feeding plate 79 are electrically connected to the lower ends of the bellows-like (which may be coiled) cables 85 each having a compressibility, and the upper ends thereof are electrically connected to the plus-side power connection 83. It is connected.

  A pair of close contact terminals 87 are provided on both sides of the opening end face 86 of the case 20, and each of them is electrically connected to the minus side power supply connection portion 84. Further, a rubber sealing material 27 is disposed on the opening end face 86.

  Next, a drain port 30 is provided at the lower part of the side plate 88 of the case 20, and a water pipe 61 disposed on the outer surface of the case 20 is connected to the drain port 30. A water distribution pipe 62 disposed in the case 20 is connected to this.

  Further, a suspension fitting 89 is attached to the upper plate 73 of the case 20, and a suspension member 90 such as a leaf spring or a wire is connected to the suspension member 89 so that it can be suspended in the nuclear reactor by the winding mechanism 11. It is.

  As already described, two suction panels 28 are attached to the outer peripheral surface of the case 20 on the left and right sides. At this time, the outer peripheral surface of the case 20 is further branched from the water distribution pipe 63 (FIG. 1). Tubes 63a and 63b are provided.

  At this time, as described above, the injection port 29 is provided on the back surface of each suction disk 28, and a branch pipe 91 communicating with the branch pipes 63 a and 63 b is connected to these on the inner surface of the suction disk 28. ing.

  One end of a pantograph-type water distribution pipe 92 is connected to the lower portion of the swing cylinder 25, and the other end of the pantograph-type water distribution pipe 92 is connected to a water distribution pipe 53 that communicates with the swing servo cylinder 50. A back pressure supply water distribution pipe 60 a communicating with the air / water pressure conversion cylinder 59 is connected to the upper portion of the swing cylinder 25.

  On the other hand, a water distribution pipe 57 communicating with the lift servo cylinder 54 is connected to the lower part of the lift cylinder 23, and a back pressure supply water distribution pipe 60 b connected to the air hydraulic pressure conversion cylinder 59 is connected to the upper part thereof. Yes.

  A second origin sensor 68 made of a proximity switch is attached to the lower side of the upper plate 73 of the case 20 and is connected to the control unit 43 via a signal cable 65c, although not shown. The second origin sensor 68 detects when the frame 21 is raised to the upper limit by the elevating cylinder 23 and outputs a signal to the control unit 43.

  A first origin sensor 67 made of a proximity switch is also attached to the lower frame 74 of the frame 21 and is also connected to the control unit 43 via a signal cable 65b, which is not shown. When the lower end of the link 24 of the swing mechanism is lowered to the lower limit by the swing cylinder 25, the first origin sensor 67 detects that and outputs a signal to the control unit 43.

  Further, a depth sensor 66 formed of a proximity switch is attached to the right frame 93 of the frame 21 and is connected to the control unit 43 via a signal cable 65a although not shown. The depth sensor 66 can detect that the processing depth by the electrode 22 has reached a set value.

  Therefore, an angle detection rod 94 arranged from the upper surface to the back surface of the electrode 22 is provided, and the angle detection rod 94 is biased toward the workpiece 26 by a spring or the like (not shown).

  The angle detection rod 94 is inclined when the machining by the electrode 22 proceeds and the electrode 22 is inclined in the direction of the arrow C. When the machining depth by the electrode 22 reaches a set value, this angle is detected. It is set so that the opposite end of the detection rod 94 contacts the probe 95 of the depth sensor 66.

  Therefore, if the processing depth by the electrode 22 reaches 30 mm, for example, if the angle detection rod 94 is adjusted so as to touch the depth sensor probe 95, the output signal from the depth sensor 66 can be controlled by the electrode 22. The control unit 43 can recognize that the processing depth has reached 30 mm.

  Next, the operation of the electric discharge machining system 10 according to the first embodiment will be described.

  First, the hoisting machine 11 is operated, and the processing head unit 12 is suspended in a nuclear reactor filled with reactor water. At this time, the power supply cables 64 a and 64 b, the water distribution pipes 60, 61, 62 and 63, and the signal cables 65 a, 65 b and 65 c are also fed out together with the processing head unit 12 into the reactor water in the reactor.

  And when the process head part 12 arrives at the location which needs repair, the 2nd water supply pump 47 is operated, and pressurized water is discharged in the direction opposite to the process target 26 from the injection port 29. FIG.

  As a result, the suction disk 28 is attracted to the surface of the processing object 26, a sealed space is formed in the case 20 of the processing head unit 12, and the contact terminal 87 provided on the opening end face 86 of the case 20 is further processed. And are electrically connected to each other.

  Next, the third hydraulic unit 44 is operated to supply back pressure to the oscillating cylinder 25 and the elevating cylinder 23 of the processing head unit 12, and at the same time, the first hydraulic unit 40 and the second hydraulic unit 41 are operated to operate the oscillating cylinder 25. And the pressurized water in the pushing direction is supplied to the elevating cylinder 23.

  As a result, the oscillating cylinder 25 operates in the pushing direction against the back pressure, the electrode 22 takes a vertical position away from the workpiece 26, and the lifting cylinder 23 works in the pushing direction against the back pressure. Then, the frame 21 takes the upper limit position.

  Next, when the first servo motor 51 of the first hydraulic unit 40 is reversed, the piston of the oscillating cylinder 25 moves in the return direction, and the electrode 22 is inclined toward the workpiece 26 by the action of the link 24 of the oscillating mechanism. To do.

  Therefore, as a result, an electric discharge occurs between the surface of the machining target 26 and electric discharge machining for the machining target 26 is started. Thereafter, the forward rotation / reverse rotation of the first servo motor 51 is repeated, whereby the electrode 22 is moved to the arrow C. The surface of the workpiece 26 is shaved off by electric discharge machining.

  During this time, since the first water supply pump 46 is operated, the sewage containing the processing waste in the case 20 is sucked from the drain port 30 and filtered by the filter 48 to become purified water, and then returned to the water tank 45. Thereafter, the purified water in the water tank 45 is returned from the water supply port 31 into the case 20 again.

  As described above, since the sewage containing the processing waste in the case 20 is discharged to the outside by the operation of the first water supply pump 46 and the purified water is newly supplied, the processing characteristics are deteriorated by the processing waste. Can be prevented.

  At this time, since the inside of the case 20 is completely isolated from the outside by the sealing material 27, there is no possibility that the processing waste flows out to the outside.

  At this time, the angle detection rod 94 also tilts with the swinging motion of the machining electrode 22, and the depth sensor 66 detects this when the machining depth by the electrode 22 reaches a preset value. Then, a signal is output to the control unit 43.

  In response to this, the control unit 43 temporarily stops driving the first servo motor 51 of the first hydraulic unit 40 and rotates the second servo motor 55 of the second hydraulic unit 41 by a predetermined amount to move up and down. Return the servo cylinder 54 to the required amount.

  As a result, the elevating cylinder 23 is operated, the frame 21 is moved downward together with the electrodes 22, and the processing location on the surface of the processing target 26 is changed.

  Next, the control unit 43 resumes driving of the first servo motor 51 and starts electric discharge machining for a new machining location.

  Then, the above steps are repeated, and when the frame 21 reaches the lower limit position in the case 20, the power supply is stopped and the case 20 is pulled up by the winding device 11.

  Here, the hydraulic circuit composed of the oscillating cylinder 25, the water distribution pipe 53, and the oscillating servo cylinder 50, and the hydraulic circuit composed of the elevating cylinder 23, the water distribution pipe 57, and the elevating servo cylinder 54 are not shown. Pure water is replenished as needed from the water source.

  For example, when there is no signal output from the origin sensor 67 of the oscillating cylinder 25 even though there is a signal output from the origin sensor 70 of the oscillation servo cylinder 50, the control unit 43 determines that the amount of water is insufficient. An electromagnetic valve (not shown) is opened and closed to supply pure water from a water source to the hydraulic circuit, and the piston of the swing cylinder 25 is returned to the origin.

  Similarly, even when there is a signal output from the origin sensor 72 of the lift servo cylinder 54 but no signal is output from the origin sensor 68 of the lift cylinder 23, the control unit 43 determines that the amount of water is insufficient and is shown in the figure. The electromagnetic valve that is not open is opened and closed to supply pure water from the water source to the hydraulic circuit, and the piston of the elevating cylinder 23 is returned to the origin.

  According to the electric discharge machining system 10 according to the first embodiment, the reciprocating movement of the machining electrode 22 is realized by a combination of the hydraulically driven rocking cylinder 25 and the link 24 of the rocking mechanism. There is no need to incorporate a motor for driving the electrode or a ball screw inside, and the machining head portion 12 can be made smaller and thinner accordingly.

  As a result, according to the electric discharge machining system 10 according to the first embodiment, the machining head portion 12 can be suspended in a very narrow place, and repair work can be performed. Moreover, since pure water is used as the pressure medium at this time, there is no possibility of adversely affecting the surroundings even if liquid leakage occurs.

  Further, according to the first embodiment, since the position of the machining electrode 22 is movable by driving the elevating cylinder 23, the machining head portion 12 remains fixed to the surface of the machining target 26. In this state, the machining position can be easily changed, and as a result, a relatively wide range can be machined at a time while maintaining the position accuracy.

  Furthermore, in the case of the electric discharge machining system 10 according to the first embodiment, as described above, the back pressure is constantly supplied to the swing cylinder 25 and the lifting cylinder 23 by the third water supply unit 44. The response is improved when the swing servo cylinder 50 and the lift servo cylinder 54 are operated in the return direction.

  Next, a second embodiment of the present invention will be described. Here, FIG. 3 is a conceptual diagram of the electric discharge machining system 100 according to the second embodiment, which is characterized by a mechanism for driving the elevating cylinder 23 and the swing cylinder 25 of the machining head 12. Most of the other configurations are the same as those of the first electric discharge machining system 10 described above.

  Therefore, in the following description, differences between the two systems will be mainly described, and components that are substantially common are simply denoted by the same reference numerals, and redundant descriptions are omitted.

  In FIG. 3, first, the external equipment group 101 includes a winding mechanism 11, a processing power supply unit 42, a control unit 43, a water tank 45, a first water supply pump 46, a second water supply pump 47, a filter 48, a first nozzle A flapper servo valve 102, a second nozzle / flapper servo valve 104, a tank 105, and a third water supply pump 106 are provided.

  The first nozzle / flapper servo valve 102 and the second nozzle / flapper servo valve 104 are always supplied with pressurized water from the third water supply pump 106 via the water supply pipes 107 and 108, and these servos are also supplied. Drainage from the valves 102 and 104 is returned to the tank 105 through drainage pipes 109 and 110.

  First, the first nozzle / flapper servo valve 102 is connected to the elevating cylinder 23 via a water distribution pipe 112 and a water distribution pipe 113.

  Therefore, when the pressurized water from the first nozzle / flapper servo valve 102 is supplied to the upper part of the elevating cylinder 23 via the water distribution pipe 112, the piston descends and the frame 21 of the machining head 12 is lowered, When the pressurized water from the servo valve 102 is supplied to the lower part of the elevating cylinder 23 through the water distribution pipe 113, the piston rises and the frame 21 of the machining head 12 is raised.

  Next, the second nozzle / flapper servo valve 104 is connected to the swing cylinder 25 via the water distribution pipe 114 and the water distribution pipe 115.

  Therefore, when pressurized water from the second nozzle / flapper type servo valve 104 is supplied to the upper portion of the swing cylinder 25 via the water distribution pipe 114, the piston descends and the electrode 22 rotates toward the surface to be processed. When the pressurized water from the servo valve 104 is supplied to the lower part of the swing cylinder 25 via the water distribution pipe 115, the piston rises and the electrode 22 returns in the opposite direction.

  Next, based on the conceptual diagram of FIG.4 and FIG.5, the detailed structure and operation | movement of the 1st nozzle flapper type servo valve 102 are demonstrated.

  The first nozzle / flapper servo valve 102 is provided with a motor 121 that operates according to a command supplied from the control unit 43 via a signal cable 117 (FIG. 3) and moves the drive shaft 120 to the left and right.

  Furthermore, the first flapper 122 and the second flapper 123 held by the drive shaft 120, the first valve chamber 124 facing the tip of the first flapper 122, and the second valve chamber 125 facing the tip of the second flapper 123 are faced. A first nozzle 126 and a second nozzle 127 opened in the first valve chamber 124, and a third nozzle 128 and a fourth nozzle 129 opened in the second valve chamber 125.

  First, the second nozzle 127 and the third nozzle 128 are connected to the upper opening of the elevating cylinder 23 via the water distribution pipe 112, and the first nozzle 126 and the fourth nozzle 129 are connected via the water distribution pipe 113. It is connected to the lower opening of the lifting cylinder 23.

  The first valve chamber 124 is connected to the water supply pipe 107 from the third water supply pump 106, and the second valve chamber 125 is connected to the drain pipe 109 leading to the tank 105.

  Here, the motor 121 is now controlled. First, the drive shaft 120 moves in a predetermined direction, and as shown in FIG. 4, the first nozzle 126 is closed by the first flapper 122 and the third flapper 123 performs the third operation. Assume that the nozzle 128 is closed.

  Then, the pressurized water supplied to the first valve chamber 124 via the water supply pipe 107 is sent from the opened second nozzle 127 to the upper opening of the elevating cylinder 23 via the water distribution pipe 112, and the surface of the piston 130. Pressurize (surface without piston rod).

  As a result, the piston 130 moves in the downward direction, and the water on the back surface (the surface with the piston rod) of the piston 130 passes through the water distribution pipe 113 and the fourth nozzle 129 from the lower opening to the second valve chamber. 125 reaches the inside of the tank 105 and returns to the tank 105 through the drain pipe 109.

  Next, the drive shaft 120 is moved in the opposite direction by the motor 121, and the second nozzle 127 is closed by the first flapper 122 and the fourth nozzle 129 is moved by the second flapper 123 as shown in FIG. Suppose it is closed.

  Then, since the first nozzle 126 is opened this time, the pressure water supplied to the first valve chamber 124 via the water supply pipe 107 is raised and lowered from the opened first nozzle 126 via the water distribution pipe 113. It is sent to the lower opening of the cylinder 23 and pressurizes the back surface of the piston 130.

  As a result, the piston 130 moves in the upward direction, and water on the surface side of the piston 130 reaches the second valve chamber 125 from the upper opening via the water distribution pipe 112 and the third nozzle 128, and from here. It is returned to the tank 105 through the drain pipe 109.

  Although illustration is omitted at this time, if the motor 121 is controlled and the first flapper 122 and the second flapper 123 are held in the neutral position, the water pressure applied to the piston 130 is balanced on both sides of the piston. The piston 1 can be stopped at a predetermined position.

Next, based on the conceptual diagram of FIG.6 and FIG.7, the detailed structure and operation | movement of the 2nd nozzle flapper type servo valve 104 are demonstrated. Here, also in the case of this 2nd nozzle flapper type servo valve 104, Basically, there are many configurations common to the case of the first nozzle / flapper type servo valve 102, but the following description will be given without regard to duplication.

  First, the second nozzle / flapper type servo valve 104 also operates in accordance with a command supplied from the control unit 43 via the signal cable 118 (FIG. 3) and includes a motor 141 that rotates the drive shaft 140 to the left and right. ing.

  Furthermore, the 3rd flapper 142 and the 4th flapper 143 which were hold | maintained at the drive shaft 140, the 3rd valve chamber 144 which the front-end | tip part of the 3rd flapper 142 faces, and the 4th valve chamber 145 which the front-end | tip part of the 4th flapper 143 faces. A fifth nozzle 146 and a sixth nozzle 147 opened in the third valve chamber 144, and a seventh nozzle 148 and an eighth nozzle 149 opened in the fourth valve chamber 145.

  First, the sixth nozzle 147 and the seventh nozzle 148 are connected to the upper opening of the swing cylinder 25 via the water distribution pipe 114, and the fifth nozzle 146 and the eighth nozzle 149 are connected via the water distribution pipe 115. Are connected to the lower opening of the swing cylinder 25.

  Next, the water supply pipe 108 from the third water supply pump 106 is connected to the third valve chamber 144, and the fourth valve chamber 145 is connected to the tank 105 through the drain pipe 110.

  Here, the motor 141 is now controlled. First, the drive shaft 140 moves in a predetermined direction, the fifth nozzle 146 is closed by the third flapper 142 and the seventh flapper 143 is closed by the seventh flapper 143 as shown in FIG. Assume that the nozzle 148 is closed.

  Then, the pressurized water supplied to the third valve chamber 144 via the water supply pipe 108 reaches the upper opening of the swing cylinder 25 from the opened sixth nozzle 147 via the water distribution pipe 114, and Pressurize the back side.

  As a result, the piston 150 moves in the downward direction, and the water on the surface side of the piston 150 reaches the fourth valve chamber 145 from the lower opening via the water distribution pipe 115 and the eighth nozzle 149, and from here the drain pipe It is returned to the tank 105 through 110.

  Next, the drive shaft 140 is moved in the opposite direction by the motor 141, and the sixth nozzle 147 is closed by the third flapper 142 and the eighth nozzle 149 is moved by the fourth flapper 143 as shown in FIG. Suppose it is closed.

  Then, the pressurized water supplied to the third valve chamber 144 through the water supply pipe 108 now reaches the lower opening of the swing cylinder 25 from the opened fifth nozzle 146 through the water distribution pipe 115, and the piston 150 Pressurize the surface.

  As a result, the piston 150 moves in the upward direction, and the water on the back side of the piston 150 reaches the fourth valve chamber 145 from the upper opening via the water distribution pipe 114 and the seventh nozzle 148, and the drain pipe. It is returned to the tank 105 through 110.

  At this time, although not shown, if the motor 141 is controlled and the third flapper 142 and the fourth flapper 143 are held in the neutral position, the water pressure applied to the piston 150 is balanced on both sides of the piston. The piston 1 can be stopped at a predetermined position.

  Therefore, also in the electric discharge machining system 100 according to the second embodiment, the configuration of the machining head 12 is different from the first electric discharge machining system 10 shown in FIG. It is common.

(1)
A water pipe 112 of the first nozzle / flapper servo valve 102 is connected to the upper part of the elevating cylinder 23.

(2)
A water pipe 113 of the first nozzle / flapper servo valve 102 is connected to the lower part of the elevating cylinder 23.

(3)
The other end of the pantograph type water distribution pipe 92 is connected to the water distribution pipe 114 of the second nozzle / flapper type servo valve 104. However, the point that one end of the pantograph type water distribution pipe 92 is connected to the lower part of the swing cylinder 25 is the same.

(Four)
A water distribution pipe 115 of the second nozzle / flapper servo valve 104 is connected to the upper portion of the swing cylinder 25.

(Five)
The first origin sensor 67, the second origin sensor 68, and the signal cables 65b and 65c do not exist.

  Hereinafter, the operation of the electric discharge machining system 100 according to the second embodiment will be described.

  First, the hoisting machine 11 is operated, and the processing head unit 12 is suspended in a nuclear reactor filled with reactor water. At this time, the power supply cables 64a and 64b, the water distribution pipes 112, 113, 114 and 115, and the signal cable 65a are also fed out into the reactor water in the reactor together with the processing head unit 12.

  And when the process head part 12 arrives at the location which needs repair, the 2nd water supply pump 47 is operated, and pressurized water is discharged in the direction opposite to the process target 26 from the injection port 29. FIG.

  As a result, the suction disk 28 is attracted to the surface of the processing object 26, a sealed space is formed in the case 20 of the processing head unit 12, and the contact terminal 87 provided on the opening end face 86 of the case 20 is further processed. And are electrically connected to each other.

  Next, the motor 121 of the first nozzle / flapper servo valve 102 is rotated in a predetermined direction, and the water pressure is supplied to the lower portion of the elevating cylinder 23 through the water distribution pipe 113 in the state shown in FIG.

  As a result, the elevating cylinder 23 operates in the pushing direction (upward direction), and the frame 21 takes the upper limit position.

  At the same time, the motor 141 of the second nozzle / flapper servo valve 104 is rotated in a predetermined direction, and the water pressure is supplied to the lower portion of the swing cylinder 25 through the water distribution pipe 115 in the state shown in FIG.

  As a result, the swing cylinder 25 operates in the return direction, and the electrode 22 takes a vertical position away from the workpiece 26.

  Next, when the motor 141 of the second nozzle / flapper type servo valve 104 is reversed, the piston 150 of the swing cylinder 25 moves in the pushing direction, and the electrode 22 is moved to the processing object 26 side by the action of the link 24 of the swing mechanism. Be inclined to.

  As a result, an electric discharge occurs between the electrode 22 and the surface of the workpiece 26, electric discharge machining for the workpiece 26 is started, and thereafter, the forward rotation / reverse rotation of the motor 141 is repeated, whereby the electrode 22 moves in the direction of arrow C. And the surface of the workpiece 26 is scraped off.

  During this time, since the first water supply pump 46 is operated, the sewage containing the processing waste in the case 20 is sucked from the drain port 30 and filtered by the filter 48 to become purified water, and then returned to the water tank 45. Thereafter, the purified water in the water tank 45 is returned from the water supply port 31 into the case 20 again.

  As described above, since the sewage containing the processing waste in the case 20 is discharged to the outside by the operation of the first water supply pump 46 and the purified water is newly supplied, the processing characteristics are deteriorated by the processing waste. Can be prevented.

  At this time, since the inside of the case 20 is completely isolated from the outside by the sealing material 27, there is no possibility that the processing waste flows out to the outside.

  At this time, the angle detection rod 94 also tilts with the swinging motion of the machining electrode 22, and the depth sensor 66 detects this when the machining depth by the electrode 22 reaches a preset value. Then, a signal is output to the control unit 43.

  Accordingly, the control unit 43 that has received this rotates the motor 121 of the first nozzle / flapper type servo valve 102 by a predetermined amount while keeping the electrode 22 away from the object to be processed 26, and the first nozzle 126. And the third nozzle 128 are both closed.

  As a result, the piston 130 of the elevating cylinder 23 is lowered, the frame 21 is moved downward together with the electrodes 22, and the machining location on the surface of the machining target 26 is changed.

  Therefore, in this state, the control unit 43 holds the first flapper 122 and the second flapper 123 of the first nozzle / flapper servo valve 102 in the neutral position, fixes the position of the piston 130, and then controls the control unit 43. Restarts the driving of the motor 141 of the second nozzle / flapper servo valve 104 and starts electric discharge machining for a new machining position.

  Then, the above steps are repeated, and when the frame 21 reaches the lower limit position in the case 20, the power supply is stopped and the case 20 is pulled up by the winding device 11.

  Accordingly, also in the electric discharge machining system 100 according to the second embodiment, the reciprocating rotation of the machining electrode 22 is realized by the combination of the hydraulically driven rocking cylinder 25 and the rocking mechanism link 24. There is no need to incorporate an electrode driving motor or ball screw in the case 20, and the machining head portion 12 can be made smaller and thinner accordingly.

  As a result, also by the electric discharge machining system 100 according to the second embodiment, the machining head portion 12 can be suspended in an extremely narrow place, and repair processing can be performed. Moreover, since pure water is used as the pressure medium at this time, there is no possibility of adversely affecting the surroundings even if liquid leakage occurs.

  Also in the second embodiment, since the position of the processing electrode 22 is movable by driving the elevating cylinder 23, the processing head portion 12 remains fixed to the surface of the processing target 26. In this state, the processing position can be easily changed, and as a result, a relatively wide range can be processed at a time while maintaining the position accuracy.

  Furthermore, also in the case of the electric discharge machining system 100 according to the second embodiment, the back pressure is constantly supplied to the swing cylinder 25 and the lift cylinder 23 by the third water supply unit 44. The response when the cylinder 50 and the lift servo cylinder 54 are operated in the return direction is also improved.

  As a result, it is possible to perform the repairing process by hanging the machining head portion 12 in an extremely narrow place.

  Moreover, since pure water is used as the pressure medium, even if liquid leakage occurs, the surroundings are not adversely affected.

  Also in this second embodiment, since the position of the machining electrode 22 is movable by driving the elevating cylinder 23, the machining head portion 12 remains fixed to the surface of the workpiece 26. In this state, the processing position can be easily changed, and as a result, a relatively wide range can be processed at a time while maintaining the position accuracy.

  Further, in the case of the electric discharge machining system 100 according to the second embodiment, the first hydraulic unit 40 (the swing servo cylinder 50, the first servo motor 51, the ball screw 52) in the electric discharge machining system 10 according to the first embodiment. Instead of this, a second nozzle / flapper servo valve 104 is provided to drive the swing cylinder 25, and the second hydraulic unit 41 (elevating servo cylinder 54, second servo motor 55, ball screw 56) is also used. Instead, the first nozzle / flapper servo valve 102 is provided to drive the elevating cylinder 23, so that the external equipment group 101 can be downsized and improved in durability.

  Further, since the liquid circuit is directly controlled by the first nozzle / flapper servo valve 102 and the second nozzle / flapper servo valve 104, it is not necessary to provide any sensors for detecting the origin position. According to the electric discharge machining system 100 according to the second embodiment, simplification of the configuration and ease of control can be realized.

  By the way, the above describes an embodiment in the case where the present invention is applied to underwater electric discharge machining in a nuclear reactor, and therefore water pressure driving is assumed. However, the present invention can also be applied to other processing objects. In this case, it is not necessary to limit the pressure medium to water. In the processing object, for example, a processing liquid used for electric discharge machining, Needless to say, it can be hydraulically driven by the same liquid as kerosene (kerosene) or pneumatically.

  Here, in the case of pneumatic driving, since there is no problem even if air leaks into the machining fluid used for electric discharge machining, it can be applied.

It is a block block diagram which shows 1st Embodiment of the electrical discharge machining system by this invention. It is a perspective view which shows an example of the process head part in embodiment of this invention. It is a block block diagram which shows 2nd Embodiment of the electrical discharge machining system by this invention. It is explanatory drawing of the 1st nozzle flapper type servo valve in the 2nd Embodiment of this invention. It is other explanatory drawing of the 1st nozzle flapper type servo valve in the 2nd Embodiment of this invention. It is explanatory drawing of the 2nd nozzle flapper type servo valve in the 2nd Embodiment of this invention. It is other explanatory drawing of the 2nd nozzle flapper type servo valve in the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10: Electrical discharge machining system 11: Winding mechanism 12: Processing head part 13: External equipment group 20: Case 21: Frame 22: Electrode 23: Lifting cylinder 24: Link of swing mechanism 25: Swing cylinder 26: Processing object 27: Seal member 28: Bellows type suction plate 29: Injection port 30: Drain port 31: Water supply port 40: First hydraulic unit 41: Second hydraulic unit 42: Processing power supply unit 43: Control unit 44: Third hydraulic unit 45: Water tank 46: 1st water supply pump 47: 2nd water supply pump 48: Filter 50: Oscillation servo cylinder 51: 1st servo motor 52: Ball screw 53: Water distribution pipe 54: Lifting servo cylinder 55: 2nd servo motor 56: Ball screw 57 : Water distribution pipe 58: Compressor 59: Air hydraulic pressure conversion cylinder 60: Water distribution pipe 60a, 60b: Water distribution pipe Pipes 61, 62, 63: Distribution pipes 64a, 64b: Feed cables 65a-65c: Signal cable 66: Depth sensor 67: First origin sensor 68: Second origin sensor 69a-69d Signal cable 70, 72: Origin sensor 73 : Upper plate 74: Lower frame 75: Flange 76: Guide rod 77: Lifting cylinder drive shaft 78: Upper frame 79: Power supply plate 80: Electrode support member 81: Support shaft 82: Oscillating cylinder drive shaft 83: Plus side power supply connection Portion 84: Negative side power supply connection portion 85: Bellows-shaped cable 86: Case opening end surface 87: Contact terminal 88: Side plate 89: Hanging bracket 90: Hanging member 92: Pantograph type water pipe 93: Right frame 94: Angle detection Rod 95: Depth sensor probe 100: Second electric discharge machining system 101: External equipment section 102: First nozzle / flapper type Servo valve 104: Second nozzle / flapper servo valve 105: Tank 106: Third water supply pump 107, 108: Water supply pipe 109-115: Water distribution pipe 117, 118: Signal cable 120: Drive shaft 121: Motor 122: No. 1 flapper 123: second flapper 124: first valve chamber 125: second valve chamber 126: first nozzle 127: second nozzle 128: third nozzle 129: fourth nozzle 130: piston 140: drive shaft 141: motor 142 : Third flapper 143: fourth flapper 144: third valve chamber 145: fourth valve chamber 146: fifth nozzle 147: sixth nozzle 148: seventh nozzle 149: eighth nozzle 150: piston

Claims (10)

In an electric discharge machining system in which an electric discharge machining is performed using a machining electrode provided in the machining head portion using a machining head portion submerged in a liquid filled in a machining target,
Using a fluid pressure operating cylinder that operates with either the same fluid or air pressure medium as the liquid, and a fluid pressure supply source that supplies the pressure medium to the fluid operating cylinder,
The fluid pressure operating cylinder is provided in the processing head portion, and the pressurized fluid is supplied to the fluid pressure operating cylinder from the fluid pressure supply source installed outside the liquid filled in the processing target,
An electric discharge machining system configured to control the operation of the electrode for electric discharge machining by the fluid pressure operation cylinder. In the electric discharge machining system according to claim 1,
The fluid pressure cylinder is
An oscillating cylinder that moves the machining electrode in a direction substantially perpendicular to the machining surface to be machined, and an elevating cylinder that moves the machining electrode in a direction substantially parallel to the machining surface to be machined. There are two types,
The fluid pressure source is
There are two types of electric discharge machining systems: a first pressure unit that supplies the pressure medium to the swing cylinder and a second pressure unit that supplies the pressure medium to the elevating cylinder. In the electric discharge machining system according to claim 2,
A third pressure unit for supplying a pressure medium to the swing cylinder and the piston of the elevating cylinder;
An electric discharge machining system configured to urge the swing cylinder and the piston of the elevating cylinder in a return direction by the pressure medium. In the electric discharge machining system according to claim 3,
The electrical discharge machining system, wherein the third pressure unit includes at least air pressure generating means and air-hydraulic pressure converting means for converting air pressure into liquid pressure. An electrode for electric discharge machining, an oscillating cylinder for oscillating the electrode with respect to the surface to be processed, and a surface of the object to be processed in a case having an opening in contact with the surface to be processed. A machining head portion that houses a lifting cylinder for moving in parallel with
A first nozzle / flapper type servo valve that alternately supplies pressure medium to the elevating cylinder via a pair of pipes in two directions, ie, reciprocating the piston;
The rocking cylinder is provided with a second nozzle / flapper type servo valve that alternately supplies pressure medium from two forward and reverse directions via a pair of pipes and reciprocates the piston. EDM system. In the electric discharge machining system according to claim 5,
The first nozzle flapper servo valve is
A first valve chamber to which a pressure medium supply pipe is connected;
A second valve chamber to which a pressure medium discharge pipe is connected;
A first nozzle having one end opened in the first valve chamber and the other end connected to one end of the elevating cylinder via a first pipe;
A second nozzle having one end opened in the first valve chamber and the other end connected to the other end of the elevating cylinder via a second pipe;
A third nozzle having one end opened in the second valve chamber and the other end connected to the other end of the elevating cylinder via the second pipe;
A fourth nozzle having one end opened in the second valve chamber and the other end connected to one end of the elevating cylinder via the first pipe;
A first flapper that alternately closes the first nozzle and the second nozzle in the first valve chamber;
A second flapper that alternately closes the third nozzle and the fourth nozzle in the second valve chamber;
A first motor that drives the first flapper and the second flapper,
The second nozzle flapper servo valve is
A third valve chamber to which a pressure medium supply pipe is connected;
A fourth valve chamber to which a pressure medium discharge pipe is connected;
A fifth nozzle having one end opened in the third valve chamber and the other end connected to one end of the swing cylinder via a third pipe;
A sixth nozzle having one end opened in the third valve chamber and the other end connected to the other end of the swing cylinder via a fourth pipe;
A seventh nozzle having one end opened in the fourth valve chamber and the other end connected to the other end of the swing cylinder via the fourth pipe;
An eighth nozzle having one end opened in the fourth valve chamber and the other end connected to one end of the swing cylinder via the third pipe;
A third flapper that alternately closes the fifth nozzle and the sixth nozzle in the third valve chamber;
A fourth flapper for alternately closing the seventh nozzle and the eighth nozzle in the fourth valve chamber;
An electric discharge machining system comprising: a second motor for driving the third flapper and the fourth flapper. In the electric discharge machining system according to claim 5,
A seal member disposed on an end face of the opening of the case;
An adsorbing member for fixing the case to a surface to be processed;
Fluid pressurizing means for supplying a pressure medium for urging the case toward the workpiece;
An electric discharge machining system comprising an injection port for discharging the pressure medium in a direction opposite to the machining target. In the electric discharge machining system according to claim 5,
A drain outlet for discharging the fluid filled in the case to the outside;
A water inlet for supplying new water into the case;
A pump for sucking water in the case through a water pipe connected to the drain port;
An electric discharge machining system comprising: a water source that supplies water into the case through a water pipe that is connected to the water supply port. In the electric discharge machining system according to claim 1 or 5,
A depth sensor for detecting a processing depth by the electrode, the processing head unit;
An electrical discharge machining system comprising: a control unit that drives the lifting cylinder to move the machining position when a signal indicating that the machining depth has reached a set value is output from the depth sensor. . In the electric discharge machining system according to claim 1 or 5,
An electric discharge machining system comprising a transfer means for suspending the machining head and transporting the machining head to the vicinity of the machining target.

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