The present invention relates to an anode and a high-speed plating machine provided with the same.
Undermentioned Patent Document 1 discloses a conventional high-speed plating machine. The high-speed plating machine includes a closed container constructed of a metal cylinder serving as an anode and lid members integrally connected to both ends of the metal cylinder respectively. The metal cylinder is made from copper and has an inner surface and end surfaces on all of which thin films of platinum are deposited respectively. The two opposed lid members are provided with respective insertion holes through which plug members are slidingly inserted. The plug members hold an article to be plated, therebetween and constitute a part of a holding device. The plug members also serve as power supplying members which are brought into contact with the article to apply negative voltage to the article.
The high-speed plating machine also includes a power-supply unit which energizes the metal cylinder and the plug members so that positive voltage is applied to the metal cylinder and the negative voltage is applied to the article to be plated. The high-speed plating machine further includes a circulation unit which comprises a pump circulating a plating solution so that the plating solution flows in the closed container.
In the high-speed plating machine, the article to be plated held between the plug members is put into the closed container and the pump is then driven so that the plating solution flows in the closed container. The positive voltage is applied to the metal cylinder and the negative voltage is applied via the plug members to the article, with the result that a high-speed plating can be carried out with a plating time being reduced.
Patent Document 1: Japanese Patent Application Publication No. JP-A-S55-138097
However, since the high-speed plating machine disclosed in Patent document 1 performs the plating with a larger current density as compared with general plating machines, the thin platinum films electrodeposited on the inner surface of the metal cylinder are sometimes peeled off or wasted in a short time period. Uniform plating cannot be carried out when the thin platinum films electrodeposited on the inner surface of the metal cylinder are peeled off or wasted. This increases a replacement frequency of the metal cylinder and costs for additional processing of thin platinum films in the high-speed plating machine.
The present invention was made in view of the foregoing circumstances and a subject matter to be overcome is to provide an anode which can perform a desirable plating for a longer period of time and also to provide a high-speed plating machine provided with the anode.
An anode of the present invention is cylindrical and forms a space between an article to be plated disposed therein and itself, in which space a plating solution flows. Positive voltage is applied to the anode. The anode includes an electrically conductive outer cylinder and an inner cylinder welded to be in contact with an inner surface of the outer cylinder. The inner cylinder is formed of a plate material made from platinum.
In the anode, since the inner cylinder formed of the plate material made from platinum is welded to the inner surface of the outer cylinder, the inner cylinder can strongly adhere closely to the electrically conductive outer cylinder. This can prevent peel-off of the inner cylinder formed of the platinum plate material from the inner surface of the outer cylinder during a plating process. Further, since the inner cylinder is formed of the platinum plate material, a consumption of platinum by execution of electroplating can be rendered smaller than a thin film of electrodeposited platinum. Thus, this anode can reduce a replacement frequency of the anode and additional processing costs.
Accordingly, the anode and the high-speed plating machine provided with the anode can perform plating in good condition for a long period of time.
An embodiment of the high-speed plating machine provided with the anode of the present invention will be described with reference to the drawings.
The high-speed plating machine of the embodiment includes an anode 10, a first power-supplying member 20 which is brought into contact with the anode 10 to apply positive voltage to the anode 10, second power-supplying members 30 which are brought into contact with an article 1 to be plated serving as a workpiece to apply negative voltage to the article 1, a holding device 40 including holding members 41 which hold the article 1, a pressurizing unit 50 supplying air into a holding chamber 45 housing the holding members 41 thereby to pressurize an atmosphere in the holding chamber 45, a circulation unit 60 circulating a plating solution, and a power supply unit 70 energizing the anode 10 and the second power-supplying members 30, as shown in
The anode 10 is cylindrical in shape and is disposed to extend in a vertical direction. The anode 10 has an outer cylinder 11 formed of a plate material made from titanium and an inner cylinder 12 formed of a plate material made from platinum, as shown in
The anode 10 is manufactured in the following manner. Firstly, a flat plate material 12A made from platinum is overlapped with a flat plate material 11A made from titanium, and the overlapped sides are welded together by electrical resistance welding, so that the plate materials are manufactured into a double structure plate material 10A (see
Since the inner cylinder 12 comprised of the platinum plate material 12A is welded onto an inner periphery of the electrically conductive outer cylinder 11 made from titanium thereby to be formed into the anode 10, the inner cylinder 12 comprised of the platinum plate material 12A can be attached firmly to the electrically conductive outer cylinder 11. This can reduce peel-off of the inner cylinder 12 comprised of the platinum plate material 12A from the inner periphery of the outer cylinder 11 during the plating process. Further, since the inner cylinder 12 is formed of the platinum plate material 12A, an amount of wear of platinum caused by electrical plating can be rendered smaller than a thin film of electrodeposited platinum. This can reduce a replacement frequency of the anode 10 and additional processing costs.
Accordingly, the anode 10 and the high-speed plating machine provided with the anode 10 can perform plating in good condition for a long period of time.
Further, the anode 10 is formed by overlapping the flat platinum plate material 12A with the flat titanium plate material 11A and thereafter by butting the end surfaces with each other and welding the end surfaces together. As a result, the cylindrical anode 10 can easily be formed which is comprised of the outer cylinder 11 formed of the flat titanium plate material 11A and the inner cylinder 12 formed of the flat platinum plate material 12A.
The first power-supplying member 20 is formed of a first member 21 and a second member 22 as shown in
The anode 10 has an upper end supported by an upper receiving member 80 and a lower end supported by a lower receiving member 90, as shown in
The upper receiving member 80 has an outer shape of rectangular parallelepiped and includes an upper space 81 open vertically upward and a lower space 82 continuous from a lower end of the upper space 81 and open vertically downward, as shown in
The upper end of the anode 10 on which the ring member 13 is fitted is inserted into the lower space 82 of the upper receiving member 80, as shown in
The lower receiving member 90 has an outer shape of rectangular parallelepiped and includes an upper space 91 open vertically upward and a lower space 92 continuous from a lower end of the upper space 91, as shown in
The lower space 92 of the lower receiving member 90 has a plating solution inlet 93 extending continuously in a horizontal direction and open in a side surface of the lower receiving member 90, as shown in
The support rod 15 has an upper end with a recess 16 open upward. A lower end of the columnar article 1 to be plated is inserted into the recess 16. The support rod 15 also has a lower end which is connected to a piston rod of an air cylinder (not shown). Accordingly, the support rod 15 can be moved upward and downward on a central axis of the anode 10 by driving the air cylinder. Two corrosion-resistant O-rings R3 and a dust seal S1 are interposed between an inner periphery of the insertion hole 94 and the support rod 15. This can prevent dust from entering inside from the outside as well as the plating solution from leaking through a gap between the insertion hole 94 and support rod 15.
The upper receiving member 80 has two opposed sides through each one of which two through holes 84 extend linearly toward the upper space 81, as shown in
Each one of the second power-supplying members 30 is formed into a columnar shape and has a forward/backward movement direction corresponding to an axial direction thereof. Two corrosion-resistant O-rings R4 are interposed between the outer periphery of each power-supplying member 30 and an inner periphery of each through hole 84, as shown in
Each second power-supplying member 30 has a distal end notched into a V shape such that a middle part thereof or a valley of the V shape is located backward relative to both sides thereof in a planar view, as shown in
Accordingly, the second power-supplying members 30 and the high-speed plating machine provided with the second power-supplying members 30 can perform plating in good condition for a long period of time.
The second power-supplying members 30 will be manufactured as follows. Firstly, as shown in
The holding device 40 has a base member 85 including a lower part inserted into the upper space 81 of the upper receiving member 80 from above, as shown in
The base member 85 has a housing part 86 which is open vertically upward and has a central lower part with a communication hole 87 open vertically downward. The housing part and the communication hole 87 have respective inner peripheries which are concentrically circular in horizontal cross-section. The communication hole 87 has a diameter which is smaller than that of the inner periphery of the communication hole 87 and slightly larger than that of the article 1 to be plated, so that the article 1 can be inserted through the communication hole 87.
The housing part 86 houses a pair of holding members 41. A holding chamber 45 is thus defined by the housing part 86 of the base member 85 and a seal cover 88 closing an upper part of the base member 85. The seal cover 88 has a disc-shaped upper surface 88A and a side surface 88B extending downward from a peripheral edge of the upper surface 88A. The upper surface 88A has an air inlet 89 extending therethrough. An air tube 52 has one of two ends which is connected to the air inlet 89 and the other end which is connected to a compressor 51. The pressurizing unit 50 thus includes the compressor 51 and the air tube 52. The seal cover 88 can be moved by a moving apparatus (not shown) to a position where the upper opening of the base member 85 is closed by the seal cover 88, at which position the seal cover 88 is downwardly pressed. An O-ring R6 is interposed between the upper surface of the base member 85 and undersides of side surfaces of the seal cover 88. This can prevent air from leaking through a gap between the base member 85 and the seal cover 88.
The holding members 41 include holding member bodies 42 and abutting parts 43 respectively. Each holding member body 42 is formed into a shape of semicircular column and includes a middle part which extends along an axis of flat surface and forms a recess 44A recessed into a semicircular column shape. The recess 44A is formed to be larger than the outer diameter of the columnar article 1 to be plated. The holding member bodies 42 are disposed so that the flat surfaces 44B are opposed to each other.
Each abutting part 43 is formed of a sponge sheet 46 which is formed into a rectangular shape in a planar view as viewed from above, as shown in
The holding member bodies 42 have respective sides which are opposed to each other and are each formed with two grooves 47A and 47B which extend horizontally at two locations spaced away from each other in a heightwise direction in order to hold the sponge sheet 46 therein, as shown in
The base member 85 has two sides perpendicular to sides of the upper receiving member 80, into which sides the second power-supplying members 30 are inserted, respectively, as shown in
The piston rods 121 of the air cylinders 120 have distal ends which are connected to the holding member bodies 42 in the holding chamber 45 of the base member 85, respectively. The holding members 41 are configured to be movable between respective backward positions and forward positions. When the holding members 41 are located at the respective backward positions, respective flat surfaces 44B of the holding member bodies 42 and respective end surfaces of the sponge sheets 46 are separated from each other, and parts of arc-shaped sides of the holding member bodies 42 are in abutment against the inner periphery of the base member 85. When the holding members 41 are located at the respective forward positions, the opposed end surfaces of the sponge sheets 46 are in contact with each other, and the abutting parts 43 of the sponge sheets 46 closely abut against respective portions of the outer periphery of the article 1 at the same level from both sides of the article 1 thereby to hold the article 1 therebetween.
A corrosion-resistant O-ring R8 is interposed between the underside of the holding member body 42 and the bottom of the housing part 86 of the base member 85, as shown in
The circulation unit 60 includes a circulation path 63, a plating solution control tank 64 and a pump 65 as shown in
The power supply unit 70 includes the power supply 75 which is connected so as to apply positive voltage to the anode 10 via the first power-supplying member 20 and so as to apply negative voltage to the article 1 to be plated via the second power-supplying members 30, as shown in
A plating process performed by the high-speed plating machine thus constructed will now be described as follows.
Firstly, when the second power-supplying members 30 and the holding members 41 are located at the respective backward positions and the support rod 15 is in the raised state, the high-speed plating machine is on standby for the lowering of the article 1 gripped in the upper end thereof by a chuck 5, as shown in
Further, the piston rod of the air cylinder (not shown) connected to the lower end of the support rod 15 is lowered with the lowering of the chuck 5 gripping the upper end of the article 1, so that the article 1 is lowered to a plating position. More specifically, the article 1 is disposed so that a space in which the plating solution flows is formed between the anode 10 and the article 1.
In this state, the piston rods 111 of the air cylinders 110 are moved forward which are connected via the gripping members 130 to the rear ends of the second power-supplying members 30, respectively. More specifically, the second power-supplying members 30 are moved to the respective forward positions toward the article 1. The distal ends of the second power-supplying members 30 are brought into contact with the upper periphery of the article 1 to hold the article 1, as shown in
Subsequently, the piston rods 121 of the air cylinders 120 connected to the holding member bodies 42 of the holding members 41 are moved forward, respectively. More specifically, the abutting parts 43 of the sponge sheets 46 are moved to the forward positions where the abutting parts 43 of the sponge sheets 46 closely abut against respective portions of the outer periphery of the article 1 at the same level from both sides of the article 1 thereby to hold the article 1 therebetween, as shown in
Next, the seal cover 88 is moved by the moving apparatus to a position where the seal cover 88 closes the upper opening of the base member 85, as shown in
The article 1 is disposed on the axis of the anode 10 in this state. More specifically, the inner periphery of the anode 10 is spaced away from the outer periphery of the article 1 lengthwise at a constant distance, so that the plating solution flows into the space.
Next, the pump 65 of the circulation unit 60 is driven to supply the plating solution in the plating solution control tank 64 to the plating solution inlet 93 of the lower receiving member 90 and thereafter to circulate the plating solution through the circulation path 63, that is, sequentially through the lower receiving member 90, the anode 10, the upper receiving member 80 and the plating solution outlet 83 back into the plating solution control tank 64. The plating solution flows between the anode 10 and the article 1.
The first and second power-supplying members 20 and 30 are energized by the power supply unit 70 so that positive voltage is applied to the anode 10 and negative voltage is applied to the article 1, whereby high-speed plating is carried out.
Thus, when the high-speed plating machine carries out the high-speed plating, the abutting parts 43 of the holding device 40 closely abut against the outer periphery of the columnar article 1 at the same level. Each abutting part 43 is comprised of chemical-resistant elastic sponge sheet 46. Further, the compressor 51 is configured to supply air to pressurize the atmosphere in the holding chamber 45. Accordingly, the abutting parts 43 comprised of the sponge sheet 46 are pressed by the pneumatic pressure with the result that the abutting parts 43 can closely adhere to the outer periphery of the article 1. Further, since the atmosphere in the holding chamber 45 is pressurized, the plating solution tending to leak to the holding chamber 45 side through interfaces between the abutting parts 43 and the article 1 or between the abutting parts 43 are pushed back by the pneumatic pressure. As a result, the holding device 40 can reliably prevent the plating solution from leaking from below the base member 85 into the housing part 86 of the base member 85. Further, since each abutting part 43 is comprised of the elastic sponge sheet 46, the abutting parts 43 can closely adhere to the outer periphery of the article 1 even when an outer peripheral configuration of the article 1 changes. As a result, the holding device 40 can deal with a plurality of types of articles. Still further, since the sponge sheet 46 formed into the abutting parts 43 is chemical-resistant, the abutting parts 43 can be prevented from deterioration by the plating solution with the result that leakage of plating solution can be prevented for a long period of time.
Accordingly, the holding device 40 and the high-speed plating machine provided with the holding device 40 can hold a plurality of types of articles to be plated and reliably prevent leakage of plating solution.
Upon completion of the high-speed plating, the first and second power-supplying members 20 and 30 are de-energized by the power supply unit 70. Further, the pump 65 of the circulation unit 60 is also stopped with the result that the plating solution is discharged out of the anode 10 to be stored in the plating solution control tank 64. The seal cover 88 is then moved by the moving apparatus from the position where the upper opening of the base member 85 is closed to a retreat position. The holding members 41 are then moved to the respective backward positions, the upper end of the article 1 is gripped by the chuck 5, and the second power-supplying members 30 are moved to respective backward positions. The article 1 is pushed upward by the support rod 15 while being pulled upward by the chuck 5, so that the article 1 is pulled out of the upper opening of the base member 85 with the result that the plating process is completed.
The present invention should not be limited by the foregoing embodiment described above with reference to the drawings but the scope of the invention involves the following embodiments.
(1) The anode is formed into the cylindrical shape in the foregoing embodiment. However, when an article with another shape is to be plated, the anode may be formed into a shape according to the shape of the article to be plated.
(2) The center members of the second power-supplying members are connected to the covering member by the screw in the foregoing embodiment. However, the inner periphery of the insertion space of the covering member and the outer periphery of the center member may each be formed into a tapered shape and the center member may be press fitted into the insertion space of the covering member.
(3) The covering member of the second power-supplying member covers the center member in a range wider than the part wetted with the plating solution. However, the covering member may cover at least the part wetted with the plating solution.
(4) The middle part of the long side of each sponge sheet is notched into the semicircular shape, and the notches serve as the abutting parts in the foregoing embodiment. However, the notched shape may be matched with the shape of the article. Further, no notches may be formed.
(5) The article is held by two holding members from two directions in the foregoing embodiment. However, the article may be held by three or more holding members so that the abutting parts closely abut against the outer periphery of the article at the same level.
(6) Two grooves holding the sponge sheets are provided at two heightwise spaced positions of the holding member bodies respectively in the foregoing embodiment. However, one, three or more grooves may be provided.
(7) In the foregoing embodiment, one sponge sheet or two overlapped sponge sheets are inserted into the grooves of the holding member bodies thereby to be held therein. However, three or more overlapped sponge sheets may be inserted into the grooves thereby to be held therein.
11A . . . flat plate material made from titanium
Number | Date | Country | Kind |
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2013-125552 | Jun 2013 | JP | national |
Filing Document | Filing Date | Country | Kind |
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PCT/JP2014/065049 | 6/6/2014 | WO | 00 |