JP5803573B2 - Anodizing equipment - Google Patents

Description

  The present invention relates to an anodizing apparatus.

  In general, the anodizing treatment is performed below the surface of an oxidizing electrolytic solution (hereinafter referred to as an electrolytic solution) in order to ensure energization. When anodizing is performed on a part of the surface of the object to be processed, it is necessary to prevent the electrolytic solution from coming into contact with the non-treated portion where the anodizing is not performed. For example, when anodizing is performed on a part of the surface of an aluminum-based metal workpiece, a method is known in which an elastic masking material is attached to the surface of the workpiece to cover it so that it does not come into contact with the electrolyte. (For example, refer to Patent Document 1).

  In addition, as a method for anodizing a part of the surface of an object to be processed without masking, for example, a method is known in which the boundary between the anodized portion and the non-treated portion is separated and secured at the electrolyte surface. (For example, see Patent Document 2).

JP 2006-336050 A JP-A-11-12781

  However, while the masking method of Patent Document 1 requires a masking material, it requires a process, work, and time for attaching or removing the masking material on the surface of the workpiece. For this reason, there is a problem that the productivity of the anodizing treatment is deteriorated and the cost is increased.

  Further, in the method of securing the boundary at the liquid level in Patent Document 2, the boundary between the anodized portion and the non-treated portion is unstable due to the fluctuation of the liquid level that occurs when the electrolyte is stirred or replenished. Therefore, there is a problem that a certain boundary cannot be secured.

  The present invention has been made in view of the above problems, and provides an anodizing apparatus capable of anodizing a target surface portion of an object to be processed without using a masking material. Objective.

The first problem-solving means of the present invention includes a first electrode portion that contacts a metal workpiece having a ring-shaped groove on its peripheral surface and energizes current, and an electrolyte discharge hole that faces the workpiece. A second electrode having a storage portion for storing the electrolyte solution discharged from the discharge hole and in contact with the surface of the object to be processed; and an electrolyte passage for supplying the electrolyte solution to the electrolyte solution discharge hole An electrolyte solution discharging means for discharging an excess electrolyte solution from the storage portion, an electrolyte supply means for supplying an electrolyte solution to the electrolyte passage, the first electrode portion, and the second electrode portion In the anodizing apparatus comprising: an energization means for applying a voltage to the electrolyte solution, the electrolyte discharge means includes an intake port for taking in the electrolyte solution, and a flow channel for flowing the electrolyte solution, A guide plate is provided radially from the rotation center of the electrolyte discharging means, and the guide plate A construction which is characterized in that rotate integrally with the object to be processed.

According to a second problem-solving means of the present invention, the electrolyte discharge means includes the guide plate, a ring-shaped upper guide portion provided on the upper portion of the guide plate, and a ring-shape provided on the lower portion of the guide plate. And a lower guide part .

  In the anodizing apparatus of the present invention, the object to be treated is brought into contact with the first electrode part for anodizing treatment, and electrolysis is performed by the electrolyte solution supply means from the electrolyte discharge hole of the second electrode part facing the object to be treated. When a voltage is applied between the first electrode part and the second electrode part by the energizing means in a state where the liquid is discharged and the surface of the object to be processed is in contact with the electrolytic solution, the object to be processed in contact with the first electrode part An electric current flows between the second electrode portions via the electrolytic solution, and the surface of the object to be processed can be subjected to an anodizing treatment at a portion in contact with the electrolytic solution. In addition, the electrolyte discharged from the discharge hole is stored in the storage part in contact with the object to be processed, and at this time, excess electrolyte is discharged from the storage part by the electrolyte discharge means, The surface of the object to be processed and the electrolytic solution do not come into contact with each other and the anodizing treatment is not performed. From the above, in the anodizing apparatus of the present invention, an anodizing treatment can be performed on a target portion of the surface of the object to be processed without using a masking material.

  Also, if the electrolyte stored in the reservoir becomes excessive, the excess electrolyte can be taken in from the intake, and the introduced electrolyte can move through the flow path, so the excess electrolyte The liquid can be discharged one after another.

  Further, when the electrolyte discharging means is rotated, the electrolyte taken in by the radial plate provided in the electrolyte discharging means is pushed out in the rotation direction, and centrifugal force acts on the extruded electrolyte so that it follows the radial induction plate. As a result, the electrolyte flows out of the center of rotation and moves, and the electrolyte can be discharged.

  Moreover, even if the contact state between the surface of the object to be processed and the electrolytic solution is different, the contact state between the surface of the object to be processed and the electrolytic solution is made constant by rotating the object to be processed, so that the surface of the object to be processed A certain anodizing treatment can be performed.

It is explanatory drawing of the anodizing apparatus which concerns on embodiment of this invention. It is the elements on larger scale of the electrode part which concerns on embodiment of this invention. It is a top view of the electrode part which concerns on embodiment of this invention. It is the elements on larger scale of the base | substrate which concerns on embodiment of this invention. It is a top view of the base concerning an embodiment of the present invention. It is the elements on larger scale of the middle board concerning the embodiment of the present invention. It is a top view of the middle board concerning the embodiment of the present invention. It is the elements on larger scale of the electrode main body which concerns on embodiment of this invention. It is a top view of the electrode main body concerning the embodiment of the present invention. It is the elements on larger scale of the impeller part which concerns on embodiment of this invention. It is a top view of the impeller part concerning the embodiment of the present invention.

  Embodiments of the present invention will be described below in detail with reference to the drawings.

  FIG. 1 is an explanatory diagram of an anodizing apparatus 1 according to an embodiment of the present invention. The anodizing apparatus 1 according to the present embodiment is for anodizing a piston ring groove W1 of a piston W made of an aluminum alloy. More precisely, of the three piston ring grooves W1, W2 and W3 formed from the top portion on the outer peripheral surface of the top portion of the piston W to the skirt portion, the side peripheral surface Wf including the piston ring groove W1 on the top portion side is mainly used. Anodizing treatment is performed. The anodizing apparatus 1 includes a holding means 2 (first electrode part), an electrode part 3 (second electrode part), an impeller part 4 (electrolyte discharging means), an electrolyte supply means 5, Means 6, electrolytic cell 7, and reservoir 8 are included.

  The holding means 2 includes a reduction motor 21 fixed to an elevating part of an elevating device (not shown) fixed to an upper end of a frame (not shown), and a holding shaft 22 fixed to an output shaft of the reduction motor 21. And a locking claw (not shown) that is detachably locked to the inner peripheral surface of the piston W provided at the lower end of the holding shaft 22. In the middle of the holding shaft 22 in the axial direction, a cylindrical support tool 23 that can removably fix the impeller portion 4 is attached. The support tool 23 is freely positioned in the vertical direction of the holding shaft 22. Can be changed. The locking claw is inserted in the axial direction so as to cover the inner cavity of the piston W from the lower end side, and the holding shaft 22, the piston W, and the impeller portion 4 are coaxial.

  A current collecting ring 61 constituting the energizing means 6 is fixed above the support 23 of the holding shaft 22, and the current collecting ring 61 and the locking claw are electrically energized, and the locking claw The piston W is energized via The current collecting ring 61, the holding shaft 22, and the piston W constitute an anode.

  The electrolytic solution supply means 5 includes a cooling tank 51 for cooling the electrolytic solution recovered from the electrolytic tank 7 to a predetermined temperature, a pump 52 that is a driving means for sending the electrolytic solution, and a flow rate for controlling the flow rate of the electrolytic solution. It is composed of a total 53 and a pipe 54 through which the electrolytic solution pumped from the pump 52 is passed. Further, the cooling tank 51 includes a sub tank 511 for storing the electrolytic solution, a refrigerator 512 and a heat exchanger 513 for cooling the recovered electrolytic solution, and a temperature sensor 514 that constitutes a control means for controlling the temperature of the electrolytic solution. Is provided. The pipe 54 constitutes the inflow path of the present invention.

  The electrolytic cell 7 is a container having an opening at the upper end, and is provided with a recovery port 71 for allowing the electrolytic solution supply means 5 to collect the electrolytic solution collected at the bottom of the electrolytic cell 7. Furthermore, the upper end opening of the electrolytic cell 7 is provided with an annular collar 72 for preventing the electrolyte from scattering.

  FIG. 2 is a partially enlarged view of the electrode unit 3 according to the embodiment of the present invention, and FIG. 3 is a plan view of the electrode unit 3 according to the embodiment of the present invention. The electrode unit 3 includes a rectangular substrate 31 serving as a base of the electrode unit 3, a disk-shaped intermediate plate 32 provided above the substrate 31, a ring-shaped electrode main body 33 provided above the intermediate plate 32, The conductor 34 is incorporated in the middle plate 32 in contact with the electrode body 33 and extends rightward and connected to the energizing means 6, and constitutes the cathode of the anodizing apparatus 1. Further, the intermediate plate 32, the electrode main body 33, and the conductor 34 form a storage portion 8 that stores the electrolytic solution in the inner portion.

  FIG. 4 is a partially enlarged view of the base 31 according to the embodiment of the present invention, and FIG. 5 is a plan view of the base 31 according to the embodiment of the present invention. The substrate 31 has a rectangular plate shape with rounded four corners. A shallow circular first circular recess 311 is formed on the upper surface of the substrate 31, and one end is opened at the center of the first circular recess 311 and the other end is opened on a side surface. A tunnel-shaped passage 312.

  FIG. 6 is a partially enlarged view of the intermediate plate 32 according to the embodiment of the present invention, and FIG. 7 is a plan view of the intermediate plate 32 according to the embodiment of the present invention. The intermediate plate 32 has a disc shape and has a protrusion 322 that forms a shallow circular second circular recess 321 at the center on the lower surface side, a shallow circular first circular groove 323 at the center on the upper surface side, and A stepped ridge 325 that forms a second coaxially shallow circular groove 324 is provided. Furthermore, through holes 326 having both ends opened are formed in the second circular recess 321 on the lower surface side and the second circular groove 324 on the upper surface side. Eight through holes 326 are provided in a ring shape at equal intervals. Further, a conductor 34 that is exposed to the first circular groove 323 from the outer peripheral surface thereof is incorporated in the intermediate plate 32.

  FIG. 8 is a partially enlarged view of the electrode main body 33 according to the embodiment of the present invention, and FIG. 9 is a plan view of the electrode main body 33 according to the embodiment of the present invention. The electrode body 33 has a stepped cylindrical shape with two outer peripheral portions, and communicates with the eight inflow holes 333 that open on the ring-shaped lower surface 331 and the inflow holes 333 and opens on the inner peripheral surface 332 of the electrode body 33. Eight discharge holes 334 are provided. The inflow holes 333 are located at positions corresponding to the eight through holes 326 provided in the intermediate plate 32, and the through holes 326 of the intermediate plate 32 communicate with the inflow holes 333 and the discharge holes 334 of the electrode body 33. It becomes an electrolyte passage. The opening on the inner peripheral surface 332 side of the inflow hole 333 serves as an electrolyte discharge hole 334, and all of the openings are offset toward the axis of the electrode body 33. For this reason, the electrolytic solution is discharged while being offset toward the axial center in the horizontal direction. Further, the inner circumferential surface 332 of the electrode body 33 and the first circular groove 323 on the upper surface side of the intermediate plate 32 constitute the storage portion 8, and the electrolyte discharged from the discharge holes 334 is stored in the storage portion 8. Can do. The electrode main body 33 is energized through the conductor 24 incorporated in the intermediate plate when fitted to the intermediate plate 32.

  FIG. 10 is a partially enlarged view of the impeller unit 4 according to the embodiment of the present invention, and FIG. 11 is a plan view of the impeller unit 4 according to the embodiment of the present invention. The impeller unit 4 includes a blade plate 41, a ring-shaped upper guide plate 42 provided on the upper portion of the blade plate 41, and a ring-shaped lower guide plate 43 provided on the lower portion of the blade plate 42. The upper guide plate 42 and the lower guide plate 43 have the same central axis, the lower guide plate 43 is parallel to the upper surface of the electrode body 33, and the upper guide plate 42 is spaced from the lower guide plate 43 at a distance from the inner diameter portion to the outer diameter portion. It is provided so as to become wider toward. An annular opening 44 is provided by making the inner diameter of the lower guide plate 43 larger than the inner diameter of the upper guide plate 42, and an electrolytic solution is taken from the annular opening 44. The vane plate 41 is disposed between the upper guide plate 42 and the lower guide plate 43 at equal intervals radially from the central axis, and joins the upper guide plate 42 and the lower guide plate 43. Further, a flow path 45 through which the electrolyte solution flows is constituted by the blade plate 41, the upper guide plate 42 and the lower guide plate 43. The impeller unit 4 is fixed to the holding shaft 22 via a cylindrical support 23 that is coupled to the upper surface of the upper guide plate 42 and fixed to the holding means 2, and rotates integrally.

  Further, in the present embodiment, when the electrolyte is discharged from the discharge hole 334 to the surface of the side peripheral surface Wf including the piston ring groove W1, the piston ring groove constituting the inner peripheral surface 332 of the electrode body 33 and the surface to be processed. The distance from W1 affects the effect of the anodizing treatment. That is, if the side peripheral surface Wf including the piston ring groove W1 is too close to the inner peripheral surface 332 of the electrode main body 33 serving as the cathode, there is a risk of short circuit. Conversely, if the distance between the side peripheral surface Wf including the piston ring groove W1 and the inner peripheral surface 332 of the electrode body 33 is too large, the electrolyte does not reach the side peripheral surface Wf including the piston ring groove W1 effectively, and anodization is performed. Processing is insufficient. Therefore, it is preferable that the distance between the discharge hole 334 of the electrode body 33 from the side peripheral surface Wf including the piston ring groove W1 connected to the anode is 2.0 to 15.0 mm.

  The rotation of the piston W has the effect of uniformly forming the alumite film. However, if the rotation is increased more than necessary, the electrolyte will be scattered beyond the annular collar 72 for preventing scattering. It is preferable to set to.

  A sulfuric acid aqueous solution having a sulfuric acid concentration of 150 g / l to 600 g / l is used as the electrolytic solution, the flow rate of the electrolytic solution is 1 liter / minute to 6 liter / minute, and the current density is 1 A / dm2 to 100 A / dm2. The voltage is 15V to 90V.

  Since the material of the holding means 2 requires electrical conductivity, a metal material with good electrical conductivity is preferable.

  The material of the electrolytic cell 7 is required to be acid resistant because it contacts the electrolytic solution, and is preferably made of vinyl chloride or SUS316.

  The material of the substrate 31 is preferably a corrosion-resistant material because it comes into contact with the electrolytic solution. Furthermore, since the electrolytic solution often uses a strong acid, an acid-resistant material such as SUS316 can be used.

  The material of the intermediate plate 32 is preferably a high-corrosion-resistant polymer material that requires insulation for preventing leakage of electricity and acid resistance for contact with the electrolytic solution. For example, vinyl chloride can be used.

  The material of the electrode body 33 and the conductor 34 is required to have electrical conductivity for conducting electricity and acid resistance for contacting the electrolytic solution. For example, SUS316 can be used.

  The material of the impeller part 4 is preferably insulated from the holding means 2 and the electrode part 3 so as not to impede the anodizing function. Further, since the impeller part 4 needs to be able to withstand the force caused by the flow of the electrolytic solution by contacting the electrolytic solution, A high-strength high-molecular material is preferable. For example, a glass fiber-containing tetrafluoroethylene resin can be used.

  The operation of the embodiment of the present invention will be described. The flow rate of the electrolytic solution cooled in the cooling tank 51 incorporated in the electrolytic solution supply means 5 is controlled by the flow meter 53 and sent to the electrode unit 3 by the pump 52. The electrolyte passes through a space between the first circular recess 311 on the upper surface side of the substrate 31 and the second circular recess 321 on the lower side of the intermediate plate 32 from the tunnel-shaped passage 312 of the substrate 31 in the electrode unit 3. It passes through the through hole 326 of the plate 32 and the through hole 333 of the electrode body 33 and is discharged from the discharge hole 334 to the side peripheral surface Wf including the piston ring groove W1. Further, after the electrolytic solution is discharged from the discharge hole 334 and subjected to anodizing treatment, the reservoir 8 constituted by the inner peripheral surface 332 of the electrode body 33 and the first circular groove 323 of the intermediate plate 32. It accumulates and fills up. Excess electrolyte from the storage unit 8 enters the impeller unit 4 through the annular opening 44 of the rotating impeller unit 4 and is composed of the upper guide plate 42, the lower guide plate 43, and the vane plate 41. It flows out from the outer diameter part of the impeller part 4 through the path 45 and is collected in the cooling tank 51 of the electrolytic solution supply means 5 through the recovery hole 71 at the bottom of the electrolytic tank 7. The recovered electrolytic solution is cooled by the heat exchanger 513 held by the electrolytic solution supply means 5 and sent to the electrode unit 3 again.

  The impeller unit 4 is coupled to the holding shaft 22 and rotates integrally with the holding shaft 22. When the impeller part 4 is rotated, the excess electrolyte from the storage part 8 is taken into the annular opening 44 and is moved by being swept away by the outer diameter part of the impeller part 4. By this movement, a new electrolytic solution is sucked from the annular opening 44 and the moved electrolytic solution is discharged to the electrolytic cell 7. When the impeller portion 4 is rotated in this manner, it functions as a pump that sucks and discharges the electrolyte solution, so that the electrolyte solution at a predetermined height or higher is discharged to ensure a constant liquid level H.

  The effect of the embodiment of the present invention will be described.

  In the anodizing device 1 of the present invention, the electrolyte W is supplied from the discharge hole 334 of the electrode portion 3 that is in contact with the holding means 2 and is opposed to the side peripheral surface Wf including the piston ring groove W1 for anodizing treatment. When the electrolytic solution is discharged by the supply means 5 and a voltage is applied between the holding means 2 and the electrode portion 3 by the energizing means 6 in a state where the electrolytic solution is in contact with the surface of the side peripheral surface Wf including the piston ring groove W1, An electric current flows between the side peripheral surface Wf including the piston ring groove W1 in contact with the holding means 2 and the electrode portion 3 via the electrolytic solution, and contacts the electrolytic solution on the surface of the side peripheral surface Wf including the piston ring groove W1. The part can be anodized. Further, the electrolyte discharged from the discharge hole 334 is stored in the storage portion 8 in a state of being in contact with the side peripheral surface Wf including the piston ring groove W1, and at this time, the electrolysis that has become excessive from the storage portion 8 by the impeller portion 4 The liquid is discharged, and the surface of the side peripheral surface Wf including the piston ring groove W1 is not in contact with the electrolytic solution above the liquid level H having a predetermined height, and the anodizing treatment is not performed. From the above, in the anodizing apparatus 1 of the present invention, an anodizing process can be performed on a target portion of the surface of the side peripheral surface Wf including the piston ring groove W1 without using a masking material.

  Further, when the electrolyte stored in the storage portion 8 becomes excessive, the excess electrolyte is taken in from the annular opening 44, and the introduced electrolyte can flow through the flow path 45 and move. Excess electrolyte solution can be discharged one after another.

  Further, when the impeller unit 4 is rotated, the electrolyte solution taken in by the radial blade plate 41 included in the impeller unit 4 is pushed out in the rotation direction, and the centrifugal force acts on the extruded electrolyte solution. , And the electrolyte solution can be discharged.

  Further, even if the contact state between the surface of the side peripheral surface Wf including the piston ring groove W1 and the electrolyte is different, the side peripheral surface Wf including the piston ring groove W1 is rotated by rotating the side peripheral surface Wf including the piston ring groove W1. By making the contact state between the surface and the electrolytic solution constant, the surface of the side peripheral surface Wf including the piston ring groove W1 can be subjected to constant anodic oxidation.

  Further, when the electrolytic solution is discharged, the portion facing the discharge hole 334 is strongly discharged, and the alumite film formed by the anodic oxidation treatment is held non-uniformly. Since the decelerating motor 21 for rotating the means 2 is equipped, the alumite film can be formed uniformly by discharging the electrolyte while rotating the piston W.

  Further, the discharge hole 334 is offset and opened toward the axial center of the electrode main body 33, and the axial center of the electrode main body 33 and the rotation center of the piston W are arranged in the same position. On the other hand, the electrolyte is discharged from the discharge hole 334 with an offset. Therefore, the manner in which the electrolytic solution hits the portion facing the discharge hole 334 is reduced, and the alumite film can be uniformly formed more efficiently.

  In addition, this invention is not limited to the said embodiment, You may change into the aspect shown below.

  In the embodiment of the present invention, the current collecting ring 61, the holding shaft 22, and the piston W constitute an anode. However, as long as the piston W can be energized, a configuration in which no holding means is incorporated is also possible. is there.

  In this embodiment, the flow meter 53 for controlling the flow rate of the electrolytic solution, the refrigerator 512 for cooling the electrolytic solution to a predetermined temperature, and the heat exchanger 513 are incorporated. In some cases, a configuration that does not include it is possible.

  In the present embodiment, when the electrolytic solution is discharged from the discharge hole 334 of the electrode body 33, the shape and size of the discharge hole 334 affects the effect of the anodizing treatment. When anodizing is performed, the discharge hole 334 may be elliptical or rectangular depending on circumstances. Further, as long as the uniformity of the discharge holes 334 of the electrode body 33 is ensured, the discharge holes 334 can be arranged in a plurality of stages on the inner peripheral surface of the electrode body 33.

  Further, in the present embodiment, the vane plate 41 has a shape forming a part of a spiral curve, but may be formed in another curved shape or a linear shape.

  The energizing means 6 is means for applying a voltage between the conductor 34 of the electrode section 3 and the holding means 2, and includes a DC power source (not shown), an ammeter, a voltmeter, and a rectifier (not shown) current collecting ring. It is comprised by 61 and a conventionally well-known thing can be utilized. Note that the configuration of this embodiment is not limited as long as the current density can be controlled.

1: Anodizing apparatus 2: Holding means (first electrode part)
3: Electrode part (second electrode part)
4: Impeller part (electrolyte discharging means)
5: Electrolyte supply means 6: Energizing means 7: Electrolysis tank 8: Reservoir 41: Blade (guide plate)
45: Flow path 311: First circular recess (electrolyte passage)
312: passage (electrolyte passage)
321: Second circular recess (electrolyte passage)
326: Through hole (electrolyte passage)
333: Inflow hole (electrolyte passage)
334: Discharge hole (electrolyte discharge hole)

Claims (2)

A first electrode portion that contacts a metal workpiece having a ring-shaped groove on the side peripheral surface thereof and energizes a current;
An electrolyte solution discharge hole facing the object to be processed, a storage part for storing an electrolyte solution discharged from the discharge hole and in contact with the surface of the object to be processed, and supplying an electrolyte solution to the electrolyte solution discharge hole A second electrode portion having an electrolyte passage to perform,
An electrolyte discharging means for discharging the excess electrolyte from the reservoir;
An electrolyte supply means for supplying an electrolyte to the electrolyte passage;
Energization means for applying a voltage to the first electrode portion and the second electrode portion;
In an anodizing apparatus comprising :
The electrolyte discharge means has an inlet for taking in the electrolyte and a flow path for flowing the electrolyte,
The flow path is provided with a guide plate radially from the rotation center of the electrolyte discharging means,
The anodizing apparatus characterized in that the guide plate rotates integrally with the object to be processed . The electrolyte discharge means includes the guide plate, a ring-shaped upper guide portion provided on the upper portion of the guide plate, and a ring-shaped lower guide portion provided on the lower portion of the guide plate. The anodizing method according to claim 1.

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