JP4645694B2 - Electrolytic processing method - Google Patents

Description

  The present invention relates to an electrolytic processing method and an electrolytic processing apparatus that are performed by filling an electrolytic solution between a workpiece and an electrode and supplying a current between the two, and in particular, a first hole in the workpiece, When the second hole opened in the peripheral wall portion of the first hole is formed, an edge portion which is a portion where the peripheral wall portion of the first hole and the peripheral wall portion of the second hole are in contact with each other is substantially curved. The present invention relates to an electrolytic processing method and an electrolytic processing apparatus for processing into a shape.

In the conventional electrolytic processing method, as shown in FIG. 9 (a), the shape of the electrode 102 is formed in accordance with the shape of the product, and an aqueous solution such as sodium nitrate (NaNO ₃ ) or sodium chloride (NaCl) is used. In the electrolytic solution 103, the electrode 102 and the workpiece 101 are opposed to each other with a predetermined interval, and a pulse current is supplied between the workpiece 101 and the electrode 102.

Assuming that the workpiece is an iron material, the mechanism of electrolytic machining will be described. When the current supply is started, the workpiece 101 is covered with the oxide film Fe ₂ O ₃ , and current is supplied in this state. The oxide film is dissolved in the electrolytic solution by a reaction represented by Fe ₂ O ₃ + 6H ⁺ + 2e → 2Fe ²⁺ + 3H ₂ O. Then, sludge Fe (OH) ₂ is generated by the reaction represented by Fe ²⁺ + 2OH ⁻ → Fe (OH) ₂ , while hydrogen gas is generated by the reaction represented by 2H ⁺ + 2e → H ₂ . When the current is stopped, the discharge of sludge and gas is promoted by the flow of the electrolytic solution, the base material of the workpiece 101 appears on the surface, and the surface of the workpiece 101 is again covered with the oxide film. Then, by repeatedly supplying and stopping the current, such oxide film generation, oxide film dissolution, sludge and gas generation, sludge and gas discharge are repeated, and the processing of the workpiece 101 progresses. Become.

  Here, in the conventional electrolytic processing method, as shown in FIG. 9B, the electrode 102 is sent toward the workpiece 101 as the processing proceeds, so that the distance between the electrode 102 and the workpiece 101 is constant. Therefore, the shape of the electrode 102 was transferred to the workpiece 101 so as to stabilize the flow of the electrolytic solution.

The following are known as conventional electrolytic processing apparatuses.
JP-A-9-141528

  However, in the conventional electrolytic processing method, as shown in FIGS. 10A and 10B, the workpiece 1 has a first hole 11 and a second hole 12 intersecting the first hole 11. When formed, an R portion as shown in FIG. 10C is applied to the edge portion 13 where the peripheral wall portion 11a of the first hole 11 and the peripheral wall portion 12a of the second hole 12 are in contact with each other by transfer. (Curved, rounded) Even if processing is attempted, an electrode having an R shape is inserted into the intersection of the first hole 11 and the second hole 12, and the electrode is fed as processing proceeds. Had the problem of being difficult.

  Here, the term “crossing” refers not only to the case of crossing so as to form a cross, but also to the case of crossing in a state where one of the two hits the other (for example, approximately T like the first hole 11 and the second hole 12 in FIG. 10). It also includes a case of a letter shape or a case of a substantially Y shape). For example, when the intersection of the two holes serves as a passage for high-pressure fuel, it is desirable to round the edge of the intersection to improve pressure resistance.

  Therefore, as shown in FIG. 11, the electrode 104 is inserted only from the second hole 12, and the electrolytic solution flows into the second hole 12 from the first hole 11. When an electric current is supplied between them, the edge portion 13 is electrolytically processed. However, the edge portion 13 can be processed into a substantially curved surface including a rounding process, although so-called dulling processing and deburring processing can be performed. There was a problem that I could not. Note that the insulating member 105 is opposed to a portion of the second hole 12 that is not desired to be processed.

  Also, as shown in FIG. 12, the electrode 106 is inserted only from the first hole 11, and the electrolytic solution is caused to flow into the first hole 11 through the flow path 106 b formed in the electrode 106, The edge portion 13 is processed when it is caused to flow into the second hole 12 from the hole 11, but there is a problem that it is not possible to process it into a substantially curved surface although it can still be dulled and deburred. The electrode 106 is formed with a protruding portion 106a facing the second hole 12, and the insulating member 107 is inserted into the first hole 11 to cover a portion that is not desired to be processed.

  The present invention solves the above-described problem. When the first hole and the second hole opened in the peripheral wall portion of the first hole are formed in the workpiece, the first hole is formed. It is an object of the present invention to provide an electrolytic processing method capable of processing an edge portion, which is a portion where the peripheral wall portion of the second hole and the peripheral wall portion of the second hole are in contact, into a substantially curved surface shape.

  In this specification and claims, the substantially curved surface shape means a state in which a substantially smoothly curved surface is formed, and a state in which a plurality of curved surfaces are substantially smoothly continuous (corrugated surface shape). ).

In the electrolytic processing method of the present invention, the peripheral wall portion of the first hole and the second hole of the workpiece in which the first hole and the second hole opening in the peripheral wall portion of the first hole are formed. An electrolytic processing method for processing an edge portion, which is a portion in contact with a peripheral wall portion of a hole, wherein an insulating member having a portion facing the opening portion of the second hole is disposed in the first hole. The opening of the second hole of the peripheral wall of the first hole is at least around the opening of the second hole between the insulating member and the peripheral wall of the first hole. A chamber is provided by providing a recess recessed outward in the radial direction of the first hole, and an electrode is inserted into at least one of the first hole or the second hole. The electrolyte is allowed to flow into the second hole from the hole of the second hole through the opening of the second hole. By supplying a current between, characterized by processing the edge portion.

  According to this, since the chamber becomes a liquid reservoir of the electrolytic solution, the rapid contraction of the electrolytic solution when flowing from the first hole into the second hole is suppressed, and the flow of the electrolytic solution is stabilized. Even if the first electrode and the second electrode are fixed electrodes that do not feed, the change in the flow of the electrolyte due to the change in the distance between the first electrode and the second electrode and the workpiece can be suppressed, and the stable Thus, gas and sludge can be discharged, the processing shape of the edge portion can be stabilized, and the edge portion can be processed into a substantially curved shape.

  (First Embodiment) An electrolytic processing method according to a first embodiment of the present invention will be described with reference to the drawings. As shown in FIGS. 1 and 2, a first workpiece 11 having a substantially circular cross section and a second hole 12 having a substantially circular cross section are formed in the iron workpiece 1. The second hole 12 has a smaller diameter than the first hole 11. As shown in FIG. 10, the second hole 12 intersects the first hole 11 so as to form a substantially T shape, and one end is open to the peripheral wall portion 11 a of the first hole 11. Yes. In the present embodiment, the first hole 11 is formed using an electrolytic processing apparatus including an insulating member (hereinafter referred to as an insulating member) 2, a first electrode 3, and a second electrode 4. The edge portion 13, which is a portion where the peripheral wall portion 11 a and the peripheral wall portion 12 a of the second hole 12 are in contact (that is, a portion connecting the peripheral wall portion 11 a and the peripheral wall portion 12 a) is processed.

  The insulating member 2 is formed in a bottomed substantially cylindrical shape. The upper wall portion 22 of the insulating member 2 has a substantially annular shape in which a substantially circular insertion port 23 is formed in the central portion, and has an outer diameter substantially the same as that of the first hole 11. The lower wall portion 21 of the insulating member 2 has a substantially circular shape having the same diameter as that of the first hole 11. The peripheral wall portion 24 of the insulating member 2 has a substantially cylindrical shape having an outer diameter that is larger than the insertion port 23 and smaller than the first hole 11. That is, the lower wall portion 21 and the upper wall portion 22 protrude in a bowl shape outward from the peripheral wall portion 24. A substantially circular opening 25 having a diameter larger than that of the second hole 12 is formed in the peripheral wall portion 24 at an intermediate position between the upper wall portion 22 and the lower wall portion 21.

  The first electrode 3 is formed in a substantially cylindrical shape with a bottom, and the outer diameter is substantially the same as that of the insertion port 23. An inlet 34 is formed at the upper end of the first electrode 3. Two outflow ports 31 are formed in the peripheral wall portion 33 of the first electrode 3 so as to face each other. Each outflow port 31 has a substantially circular shape having a smaller diameter than the opening 25 and a larger diameter than the second electrode 4.

  The second electrode 4 is formed in a substantially round bar shape having a smaller diameter than the second hole 12, and an insulating member 42 is disposed at the base end portion opposite to the tip end portion 41.

  Next, the arrangement | positioning procedure of the insulating member 2, the 1st electrode 3, and the 2nd electrode 4 comprised as mentioned above is demonstrated.

  In the present embodiment, first, the insulating member 2 is inserted into the first hole 11 so that the opening 25 faces the opening 12b of the second hole 12 in the peripheral wall 11a.

  Next, the first electrode 3 is inserted into the insulating member 2 from the insertion port 23 so that one of the outlets 31 faces the opening 12b. When distinguishing the outflow ports 31, 31, the outflow port 31 facing the opening 12b is referred to as an outflow port 31a, and the outflow port 31 on the opposite side is referred to as an outflow port 31b. The outflow port 31a faces the opening 12b through the opening surface of the opening 25, and a part of the first electrode 3 corresponding to the periphery of the outflow port 31a faces the periphery of the opening 12b. . As will be described later, the outflow port 31a serves as an insertion portion into which the distal end portion 41 of the second electrode 4 is inserted.

  And there is a gap between the peripheral wall 33 of the first electrode 3 and the peripheral wall 24 of the insulating member 2, and there is also a gap between the peripheral wall 24 and the peripheral wall 11 a of the first hole 11. Therefore, a space is provided between the peripheral wall portion 33 and the peripheral wall portion 11a. Further, a space is also provided between the lower wall portion 32 of the first electrode 3 and the lower wall portion 21 of the insulating member 2.

  Note that the insulating member 2 may be inserted into the first hole 11 after the first electrode 3 has been inserted into the insulating member 2.

  Next, the second electrode 4 is inserted into the second hole 12 from the opening on the side opposite to the opening 12 b with a space between the second wall 4 and the peripheral wall 12 a of the second hole 12. And the front-end | tip part 41 of the 2nd electrode 4 is protruded in the 1st hole 11 from the opening part 12b. That is, a part including the tip portion 41 of the second electrode 4 is extended from the opening 12 b into the first hole 11.

  Further, the tip 41 of the second electrode 4 is inserted through the opening 25 and inserted into the outlet 31a. Here, the fact that the tip portion 41 can be inserted into the outlet 31 a means that the opening 25 and the outlet 31 a are opposed to the opening 12 b, and the second electrode 4 is substantially in the axial direction of the second hole 12. It is inserted along. In other words, the insulating member 2, the first electrode 3, and the second electrode 4 can be correctly arranged by inserting the distal end portion 41 into the outflow port 31 a.

  Further, between the workpiece 1 and the first electrode 3 and the second electrode 4 so that the workpiece 1 is on the + side and the first electrode 3 and the second electrode 4 are on the − side, A pulse power supply 5 is connected. This connection may be made before or after the above-described arrangement of the insulating member 2, the first electrode 3, and the second electrode 4.

As described above, after disposing the insulating member 2, the first electrode 3, and the second electrode 4, an electrolytic solution (this embodiment) is placed in the first electrode 3 through the inflow port 34 by a pump (not shown). Then, NaNO ₃ ) is supplied. As shown by the arrows in FIGS. 1 and 2, the electrolyte flows out from each outlet 31 between the first electrode 3 and the insulating member 2, and further, from the opening 25, the insulating member 2 and the peripheral wall. It flows out between the part 11a. The electrolyte flowing out from the outlet 31 b flows between the peripheral wall portion 33 of the first electrode 3 and the peripheral wall portion 24 of the insulating member 2 and flows out from the opening 25. The electrolytic solution flowing out from the opening 25 flows into the second hole 12 through the opening 12b.

  The electrolytic solution is filled from the first hole 11 to the second hole in a state where the portion from the upper wall portion 22 to the lower wall portion 21 of the insulating member 2 in the first hole 11 and the inside of the second hole 12 are filled. It continues to be supplied so as to flow to the holes 12 of In addition, it does not ask | require whether the to-be-processed object 1 is arrange | positioned in the electrolyte solution tank with which the electrolyte solution was satisfy | filled.

  While supplying the electrolytic solution, a pulse current 5 supplies a pulse current between the workpiece 1 and the first electrode 3 and between the workpiece 1 and the second electrode 4. . Then, as shown by the arrows in FIG. 3, the workpiece 1 receives current from the first electrode 3 and the second electrode 4 except for the portions facing the insulating member 2 and the insulating member 42. . In particular, the corner portion 13a of the edge portion 13 passes through a part of the first electrode 3 facing the periphery of the opening portion 12b and the opening portion 12b (the peripheral portion of the opening portion 12b corresponds to the edge portion 13). Then, current is received from a part of the second electrode 4 disposed in the first hole 11 and the current is concentrated, so that the edge portion 13 is processed into a substantially curved surface shape. Further, since the current from both the first electrode 3 and the second electrode 4 is received, the processing speed of the edge portion 13 is increased and the required R (curvature radius) can be ensured. .

  Moreover, since the outflow ports 31 and 31 are provided to face the peripheral wall portion 33 of the first electrode 3 and the outflow port is not provided to the lower wall portion 32, the electrolyte is supplied from the first electrode 3. It flows out symmetrically and the deviation of the flow of the electrolyte is reduced. For this reason, the flow of the electrolyte solution that passes through the edge portion 13 is also substantially uniform along the entire circumference of the edge portion 13 and is less likely to be disturbed, and the processed shape of the edge portion 13 can be stabilized.

  Further, the opening 25 of the insulating member 2 is formed at an intermediate position between the upper wall portion 22 and the lower wall portion 21, and the outlet 31 a is arranged in accordance with the position of the opening 25. 31 a and 31 b are arranged at an intermediate position between the upper wall portion 22 and the lower wall portion 21. For this reason, the electrolytic solution flows into the opening 12b from the upper side and the lower side in FIG. 2 almost evenly, and the flow is hardly disturbed, and the processed shape of the edge portion 13 is further stabilized.

  As shown in FIG. 4, in an experiment in which the supply direction of the electrolytic solution is changed, when the electrolytic solution is supplied from the second hole 12 to the first hole 11 (positive flow direction), the edge portion 13 is In the case where corners and wrinkles are generated and electrolyte is supplied from the first hole 11 to the second hole 12 substantially along the axial direction of the second hole 12 (in the reverse flow direction), When the electrolyte solution is supplied to the second hole 12 by flowing the electrolyte solution from the first hole 11 in a direction substantially orthogonal to the axial direction of the second hole 12 (see FIG. In the lateral flow direction), the edge portion 13 was not evenly rounded. That is, in order to apply R, there is a reverse flow direction in which the electrolytic solution is supplied from the first hole 11 to the second hole 12 substantially along the axial direction of the second hole 12 as in the present embodiment. I found it good. In the experiment shown in FIG. 4, since a flow trace was generated in the case of the backward flow direction, the chamber 6 was provided in the present embodiment in order to further stabilize the flow.

  FIG. 5 shows the chamber 6 between the insulating member 2 and the peripheral wall portion 11a by disposing the peripheral wall portion 24 of the insulating member 2 away from the peripheral wall portion 11a of the first hole 11 as in this embodiment. FIG. 6 is an explanatory diagram of the state of the electrolyte solution when the chamber 6 is provided, and FIG. 6 is a diagram of the state of the electrolyte solution when the chamber 6 is not provided without separating the peripheral wall portion 24 and the peripheral wall portion 11a. It is explanatory drawing. And the flow of the site | part shown to B, C, D of Fig.5 (a) is shown to FIG.5 (b) (c) (d), The flow of the site | part shown to B, C of Fig.6 (a) is shown, It shows to FIG.6 (b) (c).

  As can be seen from FIG. 5 and FIG. 6, when the chamber 6 is not provided, as shown by the arrow in FIG. 6A, the flow suddenly contracts (rapid reduction) and the flow is disturbed. However, when the chamber 6 is provided, the rapid contraction of the flow is suppressed, the turbulence of the flow is suppressed, and the flow is relaminarized as shown in FIG. This is because, as indicated by an arrow E in FIG. 5 (d), when the chamber 6 becomes a liquid pool, the flow in the chamber 6 (arrow F) causes the flow ejected from the opening 25 to be the second. It is presumed that this is because the hole 12 is pressed to the opening 12b side.

  That is, according to the present embodiment, the chamber 6 becomes a reservoir of the electrolytic solution, so that the rapid contraction of the electrolytic solution when flowing from the first hole 11 to the second hole 12 is suppressed, and the electrolytic solution The flow stabilizes. For this reason, even if the first electrode 3 and the second electrode 4 are fixed electrodes that are not fed, the electrolyte solution due to a change in the distance between the first electrode 3 and the second electrode 4 and the workpiece 1 The change in flow can be suppressed, gas and sludge can be discharged stably, the processing shape of the edge portion 13 can be stabilized, and the edge portion 13 can be processed into a substantially curved surface shape.

  (Second Embodiment) Next, the electrolytic processing method of the second embodiment will be described. In addition, about the component corresponding to each component of 1st Embodiment, the code | symbol same as 1st Embodiment is used and the description is abbreviate | omitted suitably. As shown in FIG. 7, in the second embodiment, the shapes of the first electrode 3 and the second electrode 4 are the same as those in the first embodiment, but the shape of the insulating member 2 is different. The insulating member 2 used in the second embodiment has a substantially cylindrical shape in which the peripheral wall portion 24 has an outer diameter substantially the same as that of the first hole 11. That is, in the insulating member 2 used in the first embodiment, the lower wall portion 21 and the upper wall portion 22 protrude in a bowl shape outward from the peripheral wall portion 24, but the insulating member 2 used in the second embodiment. Then, the outer diameter of the upper wall part 22, the surrounding wall part 24, and the lower wall part 21 is made the same, and the lower wall part 21 and the upper wall part 22 do not protrude in a bowl shape.

  In the second embodiment, the periphery of the opening 12b of the second hole 12 of the workpiece 1 is omitted by cutting or the like, so that the peripheral wall 11a of the first hole 11 has a second A recess 11 b that is recessed outward in the radial direction of the first hole 11 is provided around the opening 12 b of the hole 12.

  When the insulating member 2 is inserted into the first hole 11 with the recess 11b provided, the opening 12b of the second hole 12 between the insulating member 2 and the peripheral wall portion 11a of the first hole 11 is provided. Is provided with a chamber 6. And if the 1st electrode 3 and the 2nd electrode 4 are inserted similarly to 1st Embodiment and electrolyte solution is supplied from the inflow port 34, the chamber 6 will become a liquid reservoir, and 1st Embodiment Similar effects can be obtained. Although not shown in FIG. 7, a current is supplied by a pulse power source 5 between the workpiece 1 and the first electrode 3 and the second electrode 4.

  (Third Embodiment) The first and second embodiments are processing methods in the case where the first hole 11 and the second hole 12 intersect with each other in a substantially T shape, and are shown in FIG. As described above, the first hole 11 and the second hole 12 intersect each other in a substantially cross shape, and the second hole is opposed to the peripheral wall 11a of the first hole 11 so as to face the opening 12b. The present invention can also be applied to the case where twelve openings 12c are formed. Hereinafter, an embodiment (third embodiment) in such a case will be described. In addition, about the component corresponding to each component of 1st Embodiment, the code | symbol same as 1st Embodiment is used and the description is abbreviate | omitted suitably.

  In the third embodiment, as shown in FIG. 8, the insulating member 2 is provided with another opening 26 facing the opening 25, and the insulating member 2 and the second electrode 3 are connected to the first member. Insert into hole 11. Then, the second electrode 4 is inserted into the second hole 12, the tip 41 is inserted into the first hole 11 from the opening 12b, the opening 25, the outlets 31a and 31b, the opening 26, The openings 12c are inserted in this order. As a result, the second electrode 4 passes through the first electrode 3 and intersects the first electrode 3 and also intersects the first hole 11 so as to cross the first hole 11. And the intermediate part 43 which is a part of 2nd electrode 4 becomes the form extended in the 1st hole 11 from the opening parts 12b and 12c. In addition, the front-end | tip part 41 of 3rd Embodiment is used as the insulating member.

  In this state, if the electrolytic solution and the current are supplied in the same manner as in the first embodiment, the electrolytic solution flows from the first hole 11 into the second hole 12 through the openings 12b and 12c, and the edge portion 13 is supplied. And the edge part 14 which is the peripheral part of the opening part 12c will receive an electric current from both the 1st electrode 3 and the 2nd electrode 4, an electric current concentrates on the edge parts 13 and 14 and an edge The parts 13 and 14 are processed into a substantially curved surface shape.

  (Other Embodiments) In the first, second, and third embodiments, the pulse power source 5 is used for improving the surface roughness, but a simple DC power source may be used.

  In the first embodiment, the chamber 6 is provided over the entire circumference of the first hole 11 by separating the peripheral wall portion 24 from the peripheral wall portion 11a over the entire circumference. What is necessary is just to provide at least around the opening part 12b of the 2nd hole 12 like 2nd Embodiment. This can also be realized by providing the recess 11b around the opening 12b as in the second embodiment. However, in the insulating member 2 as in the second embodiment, the insulating member 2 surrounds the opening 25. It can also be realized by indenting inward in the radial direction.

  Furthermore, an embodiment in which no gap is provided between the lower wall portion 21 of the insulating member 2 and the lower wall portion 32 of the first electrode 3 can be provided.

  That is, the present invention can take various embodiments without departing from the scope of the claims.

It is a schematic sectional drawing of the electrolytic processing apparatus of 1st Embodiment. It is a figure which shows the schematic cross section and power supply of the II-II site | part of FIG. It is explanatory drawing of the mode of the electric current flow of 1st Embodiment. It is a figure which shows the experimental result which processed by changing the supply direction of electrolyte solution, and investigated the shape of the edge part. It is explanatory drawing of the mode of the flow of electrolyte solution when providing a chamber. It is explanatory drawing of the mode of the flow of electrolyte solution when not providing a chamber. It is a schematic sectional drawing of the electrolytic processing apparatus of 2nd Embodiment. It is a figure which shows the schematic cross section and power supply of the electrolytic processing apparatus of 3rd Embodiment. It is explanatory drawing of the conventional electrolytic processing. (A) is a schematic sectional view when the workpiece is cut along a plane perpendicular to the axial direction of the first hole, and (b) is a plane along the axial direction of the first hole. The schematic perspective view when cut | disconnected, (c) is a figure of the state which processed the edge part in (b). It is explanatory drawing at the time of performing an electrochemical process by inserting an electrode only in the 1st hole. It is explanatory drawing at the time of inserting an electrode only in the 2nd hole and performing electrolytic processing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Workpiece 2 ... Insulating member 3 ... 1st electrode 4 ... 2nd electrode 6 ... Chamber 11 ... 1st hole 11a ... Peripheral wall part 11b ... Recessed part 12 ... 2nd hole 12a ... Peripheral wall part 12b, 12c ... Opening 13, 14 ... Edge 25,26 ... Opening 31 ... Outlet

Claims (1)

The peripheral wall portion of the first hole and the peripheral wall portion of the second hole of the workpiece in which the first hole and the second hole opened in the peripheral wall portion of the first hole are in contact with each other. An electrochemical machining method for machining an edge part, which is a part,
An insulating member having a portion facing the opening of the second hole is disposed in the first hole, and at least the second portion between the insulating member and the peripheral wall of the first hole. By providing a recess recessed outward in the radial direction of the first hole around the opening of the second hole around the opening of the first hole, around the opening of the second hole. Provided,
Inserting an electrode into at least one of the first hole or the second hole;
The electrolyte is allowed to flow from the first hole to the second hole through the opening of the second hole, and an electric current is supplied between the workpiece and the electrode, and the edge portion An electrolytic processing method characterized by processing the material.

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