JP2010253610A - Water jet machining device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water jet machining device capable of smoothly delivering abrasive grains without being retained in a pipe when delivering deposited abrasive grains from an abrasive grain recovery tank to a high pressure tank. <P>SOLUTION: A recovery means 30 is attached to the abrasive recovery tank 18. The recovery means 30 includes an abrasive grain suction passage 32 for sucking the abrasive grains A deposited in a lower layer part of the abrasive grain recovery tank 18, a liquid suction passage 34 for sucking supernatant liquid B existing in an upper layer part of the abrasive grain recovery tank 18, a mixing chamber 36 for mixing the abrasive grains A sucked through the abrasive grain suction passage 32 and the supernatant liquid B sucked through the liquid suction passage 34, and a delivery passage 38 for delivering the abrasive grains A and the supernatant liquid B in the mixing chamber 36 from the mixing chamber 36. In the delivery passage 38, a pump means 48 is disposed. By a suction action of the pump means 48, mixed liquid of the abrasive grains A and the supernatant liquid B is delivered. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a water jet machining apparatus for machining a workpiece by high-pressure injection of a machining liquid containing abrasive grains and a liquid.

  In the processing of a workpiece such as a composite material that is difficult in dicing using a cutting tool, cutting with a water jet has been studied. The water jet machining apparatus includes a holding table that holds a workpiece, a high-pressure tank that stores abrasive grains and liquid, and a processing liquid that contains abrasive grains and liquid from the high-pressure tank on the workpiece held on the holding table. , A catch tank for receiving the machining fluid ejected from the ejection nozzle, a filter means for separating reusable abrasive grains from the machining liquid delivered from the catch tank, and an abrasive separated by the filter means And an abrasive collection tank for receiving the grains (see Patent Document 1). In the abrasive grain recovery tank, abrasive grains to be reused are deposited in the lower layer part, and the abrasive grains are stored in a state where the supernatant liquid exists in the upper part part. Abrasive grains are sucked by a pump through a pipe, conveyed to a high-pressure tank, and reused (see Patent Document 2).

  Conventionally, a bypass pipe for supplying a liquid such as pure water is connected to a position near the abrasive recovery tank of the pipe. Liquid is supplied from the bypass pipe into the pipe, and a mixed liquid containing high-concentration abrasive grains is diluted with the liquid and conveyed to the high-pressure tank.

JP 2005-230994 A JP 2006-110687 A

  However, when the liquid is supplied in the middle of the pipe by the liquid supply bypass pipe described above, the liquid mixture in the pipe is not evenly diluted, and the concentration of the liquid mixture varies in some places. Therefore, there is a problem that the abrasive grains gradually accumulate in the pipe and the abrasive grains cannot be smoothly fed into the high-pressure tank.

  The present invention has been made in view of the above-mentioned facts, and the main technical problem thereof is that when the abrasive grains are fed from the abrasive grain recovery tank to the high pressure tank, the abrasive grains are smoothly retained without being retained in the pipe. It is to provide a possible new and improved water jet machining apparatus.

According to the present invention, as a water jet machining apparatus that achieves the main technical problem, a holding table that holds a workpiece, a high-pressure tank that stores abrasive grains and liquid in a high-pressure state, and a holding table that holds the workpiece. An injection nozzle for injecting a processing liquid of abrasive grains and liquid from the high-pressure tank onto the processed workpiece, a catch tank for receiving the processing liquid injected from the injection nozzle, and the pump sent from the catch tank A water jet processing apparatus comprising an abrasive recovery tank for recovering abrasive grains from a processing liquid,
The abrasive grain recovery tank is provided with a recovery means, and the recovery means includes an abrasive suction path for sucking deposited abrasive grains deposited in a lower layer portion of the abrasive grain recovery tank, and an upper layer of the abrasive grain recovery tank. A liquid suction path for sucking the supernatant liquid present in the section, a mixing chamber for mixing the abrasive grains sucked through the abrasive suction path and the liquid sucked through the liquid suction path, and a mixed liquid in the mixing chamber. There is provided a water jet machining apparatus comprising a delivery path for delivering from the mixing chamber.

Preferably, pump means is provided in the delivery path, and abrasive grains are sucked through the abrasive suction path by the suction action of the pump means, and the supernatant liquid is sucked through the liquid suction path, and the delivery path The mixture is delivered through
A water jet machining apparatus is provided.

  The recovery means is attached to the abrasive grain recovery tank, and the abrasive grains sucked from the abrasive suction path and the supernatant liquid sucked from the liquid suction path are mixed in the collection chamber of the recovery means and sent out from the delivery path, so that it does not stay It becomes possible to adjust the dilution to a constant concentration, and as a result, the abrasive grains do not stay in the delivery path and can be reused smoothly.

Schematic which shows the structural example of the water jet processing apparatus concerning embodiment of this invention. Schematic which shows the structural example of an abrasive grain collection tank periphery. Schematic which shows the structural example of a collection | recovery means.

  Hereinafter, a water jet machining apparatus which is the best mode for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic diagram illustrating a configuration example of a water jet machining apparatus 2 according to the present embodiment. The water jet machining apparatus 2 according to the present embodiment increases the workpiece W with a relatively free cutting line by mixing and injecting, for example, a high-pressure liquid of pure water and abrasive grains onto the workpiece W. This is a cutting device that can perform cutting (i.e., water jet processing) with high accuracy. The workpiece W to be cut by the water jet machining apparatus 2 is, for example, various semiconductor substrates such as a packaged semiconductor substrate (for example, a CSP substrate).

  As shown in FIG. 1, the water jet machining apparatus 2 according to the present embodiment includes a high pressure pump 4, a high pressure tank 6, an injection nozzle 8, a holding table 10, a table moving means 12, and a catch tank 14. The filter means 16 and the abrasive grain recovery tank 18 are provided.

  The high pressure pump 4 pressurizes the liquid supplied from the outside to generate and supply a high pressure liquid of, for example, 60 to 80 MPa. The high-pressure liquid generated by the high-pressure pump 4 is supplied into the high-pressure tank 6 through the high-pressure pipe 20. The high-pressure tank 6 is composed of a high-pressure resistant container and stores a machining liquid in which abrasive grains and a liquid are mixed. The abrasive grains are, for example, a granular material having a high hardness such as garnet, diamond, alumina oxide or the like, for example, about several tens to several hundreds μm, and contributes to increasing the cutting efficiency of the high-pressure liquid.

  The high-pressure tank 6 is further fed with a high-pressure liquid supply pipe 21a and a machining liquid delivery pipe 21b each having a length extending to the vicinity of the bottom of the high-pressure tank 6, and a mixed liquid feed having a length extending to the upper layer. An inlet pipe 21c is provided. The high-pressure liquid supply pipe 21 a is connected to the high-pressure pipe 20 and supplies high-pressure liquid near the bottom of the high-pressure tank 6. The machining fluid delivery pipe 21 b has an inlet near the bottom and communicates with the injection nozzle 8 via the high-pressure pipe 22. By the high-pressure liquid supplied from the high-pressure liquid supply pipe 21a, the abrasive grains stored in the high-pressure tank 6 are mixed with the high-pressure liquid, enter the machining liquid sending pipe 21b, and are sent to the injection nozzle 8 through the high-pressure pipe 22. Then, the machining liquid J is ejected from the ejection nozzle 8 at a high speed.

  The injection nozzle 8 for injecting the high-pressure machining fluid J includes a nozzle pipe 8a joined to the high-pressure pipe 22 and an orifice 8b attached to the tip of the nozzle pipe 8a. The holding table 10 is a plate-like member on which the workpiece is placed, and is formed in a shape corresponding to the shape of the workpiece W. The holding table 10 is slightly larger than the outer shape of the workpiece W at a portion to which the workpiece W is fixed. A small opening (not shown) is formed to allow the machining fluid J to pass therethrough.

  The holding table 10 is provided with table moving means 22. The table moving means 22 is composed of, for example, a drive mechanism such as an electric motor or a gear, and moves the holding table 10 in the horizontal direction (X-axis and Y-axis directions). By moving the holding table 10 in the X-axis and Y-axis directions which are horizontal directions by the table moving means 22, the workpiece W held by the holding table 10 is moved in the X-axis and Y-axis directions with respect to the injection nozzle 8. Move relative to. Thereby, the injection position (cutting part) of the processing liquid J with respect to the workpiece W is changed, and the workpiece W is continuously cut.

  The machining liquid J injected from the injection nozzle 8 is received by the catch tank 14 as shown in FIG. The catch tank 14 includes a water tank 24 that stores the machining liquid J that has penetrated the workpiece W, and a basket 26 that contains a plurality of buffer balls stored in the water tank 24. The machining liquid J that has penetrated the workpiece W collides with the plurality of buffer balls, and the plurality of buffer balls are stirred to weaken the momentum of the machining liquid J. Further, a drain pipe 28 is disposed on the side surface of the catch tank 14, and is connected to the filter means 16 through the drain pipe 28. The working fluid J stored in the catch tank 14 is sent to the filter means 16 through the drain pipe 28 by the suction action of a suction pump (not shown).

  The filter means 16 has passed through a drainage channel (not shown), an abrasive recovery filter (not shown) that is disposed in the drainage channel and can pass an appropriately sized abrasive grain, and an abrasive recovery filter. A pipe 32 for sending abrasive grains to the abrasive grain recovery tank 18 and a drain pump (not shown) for discharging unnecessary liquid and inappropriately sized abrasive grains to the outside through the pipe 32 are provided. . By increasing the flow rate of the liquid containing abrasive grains using the drainage pump, excessively small abrasive grains pass through the abrasive collection filter and are discharged in the water stream without sinking. Moreover, since excessively large abrasive grains cannot pass through the abrasive collection filter, they are also discharged together with the drainage. For this reason, only the abrasive grains having a size within a predetermined range suitable for cutting (for example, when the optimum grain size of the abrasive grains is about 80 μm, the grain size is in the range of 40 to 120 μm) are contained. The mixed solution passes through the abrasive recovery filter and is sent to the abrasive recovery tank 18. On the other hand, abrasive grains having a size outside the predetermined range are treated as waste liquid.

  Next, the recovery means 30 and the abrasive recovery tank 18 that are embodiments of the present invention will be described with reference to FIGS. The abrasive grain recovery tank 18 is formed in a stainless steel rectangular parallelepiped shape, and stores therein a mixed liquid containing abrasive grains that have passed through the filter means 16. A pipe 32 communicating from the filter means 16 is connected to the upper side surface of the abrasive grain recovery tank 18. A mixed liquid containing abrasive grains selected by the filter means 16 is fed from the pipe 32. The mixed liquid fed in is stored in a state where the abrasive grains A are deposited in the lower layer portion of the abrasive recovery tank 18 and separated into the supernatant liquid B in the upper layer portion. Thereafter, the abrasive grains A are sent to the high-pressure tank 6 by the collecting means 30 as needed.

  As shown in FIG. 3, the recovery means 30 includes an abrasive suction path 32 for sucking the abrasive grains A deposited in the lower layer portion of the abrasive recovery tank 18 and a supernatant present in the upper layer portion of the abrasive recovery tank 18. A liquid suction path 34 for sucking the liquid B, a mixing chamber 36 for mixing the abrasive grains A sucked through the abrasive suction path 32 and the liquid B sucked through the liquid suction path 34, and abrasive grains in the mixing chamber 36 A delivery path 38 for delivering A from the mixing chamber 36 is configured. The mixing chamber 36 is formed of, for example, a cylindrical stainless steel tube, and at both ends thereof, an abrasive suction path 32 formed of a stainless pipe that may be smaller in diameter than the mixing chamber 36, and an abrasive suction path 32. And a delivery path 38 having the same diameter. In addition, a liquid suction path 34 formed of a stainless steel tube is disposed in the upper part of the mixing chamber 36. It is preferable that at least the mixing chamber 36, the abrasive suction path 32 and the delivery path 38 are arranged in a straight line, and the abrasive suction path 32 and the delivery path 38 are formed to have the same diameter.

  Returning to FIG. 2 and continuing the description, the abrasive suction path 32 is connected to a recovery pipe 40 disposed in a lower layer portion of the abrasive recovery tank 18. One end of a liquid supply pipe 42 is connected to the liquid suction path 34. The other end 42a of the liquid supply pipe 42 is connected and fixed to a region where the supernatant liquid B exists in the upper layer portion of the abrasive grain recovery tank 18. The liquid supply pipe 42 is provided with valve means 44. The valve means 44 is constituted by a valve capable of adjusting the flow rate, such as a needle valve. The amount by which the supernatant B is sucked into the mixing chamber 36 by the valve means 44 can be adjusted.

  Furthermore, one end of a pipe 46 is connected to the delivery path 38 of the collecting means 30. The other end of the pipe 46 communicates with the mixed liquid feeding pipe 21c (see FIG. 1) of the high-pressure tank 6 through the pump means 48. The pump means 48 is constituted by, for example, a diaphragm pump. Due to the suction action of the pump means 48, the abrasive grains A are sucked into the mixing chamber 36 of the collecting means 30 through the abrasive suction path 32, the supernatant B is sucked through the liquid suction path 34, mixed in the mixing chamber 36, and passed through the delivery path 38. The liquid mixture is delivered. Thus, the collection means 30 can adjust the concentration so that the mixed solution does not stay in the pipe 46. Further, when the concentration staying in the pipe 46 changes due to changing the type and particle size of the abrasive grains A, the concentration is increased by adjusting the valve means 44 and adjusting the suction amount of the supernatant liquid B. The concentration of the mixed solution can be controlled.

  Returning to FIG. 1 and continuing the description, the abrasive grains A are diluted with the supernatant B by the pump means 48 and sent to the high-pressure tank 6 through the pipe 46. After the high-pressure tank 6 stops supplying high-pressure liquid from the high-pressure pipe 20 and returns the inside of the high-pressure tank 6 to normal pressure, the mixed liquid is inserted from the mixed-solution delivery pipe 21c. Thereafter, the high-pressure liquid is again supplied from the high-pressure pump 4 into the high-pressure tank 6 and used for processing the workpiece W.

  In the embodiment described above, the liquid suction passage 34 is adjusted by the valve means 44. However, a large number of liquid suction passages 34 of various diameters are provided in the mixing chamber 36, and the supernatant liquid B is appropriately supplied by an open / close valve. The liquid suction path 34 to be sucked may be switched. Further, each time the concentration or particle size of the abrasive grain A is changed, the liquid suction path 34 having a suitable diameter may be replaced.

2 Water jet processing device 4 High pressure pump 6 High pressure tank 8 Injection nozzle 10 Holding table 14 Catch tank 16 Filter means 18 Abrasive recovery tank 30 Recovery means 32 Abrasive suction path 34 Liquid suction path 36 Mixing chamber 38 Delivery path 48 Pump means A Abrasive grain B Supernatant liquid J Processing liquid W Workpiece

Claims (2)

A holding table for holding a workpiece, a high-pressure tank for storing abrasive grains and liquid in a high-pressure state, and a machining liquid containing abrasive grains and liquid from the high-pressure tank in the workpiece held on the holding table A water jet comprising: an injection nozzle that injects a liquid; a catch tank that receives the processing liquid injected from the injection nozzle; and an abrasive recovery tank that recovers abrasive grains from the processing liquid sent from the catch tank A device,
The abrasive recovery tank is provided with recovery means, and the recovery means includes an abrasive suction path for sucking deposited abrasive grains deposited in a lower layer of the abrasive recovery tank, and an abrasive recovery tank. A liquid suction path for sucking the supernatant liquid present in the upper layer part, a mixing chamber for mixing the abrasive grains sucked through the abrasive grain suction path and the liquid sucked through the liquid suction path, and a mixed liquid in the mixing chamber A water jet machining apparatus comprising a delivery path for delivering the liquid from the mixing chamber. Pump means is disposed in the delivery path, and abrasive particles are sucked through the abrasive grain suction path by the suction action of the pump means, and the supernatant liquid is sucked through the liquid suction path, and the mixing liquid passes through the delivery path. Liquid is delivered,
The water jet machining apparatus according to claim 1.

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