CN113439133A

CN113439133A - Workpiece holding jig and surface treatment device

Info

Publication number: CN113439133A
Application number: CN202080011919.4A
Authority: CN
Inventors: 石井胜己
Original assignee: Almex Technologies Inc
Current assignee: Almex Technologies Inc
Priority date: 2019-01-31
Filing date: 2020-01-23
Publication date: 2021-09-24
Also published as: TW202033840A; JP6909525B2; TWI716268B; JPWO2020158567A1; WO2020158567A1; KR20210123335A

Abstract

A workpiece holding jig (30) capable of holding a workpiece (20) to be surface-treated and capable of being electrically connected to a rectifier that is voltage-controlled so as to flow a constant current, wherein a conductive member capable of being electrically connected to the rectifier and the workpiece (20) includes: a common conductive member (360(361, 362, 363)); and a1 st branch conductive member and a2 nd branch conductive member branched from the common conductive member and connected to the workpiece (20), the common conductive member (360) including members (362, 363) formed of a material having a maximum resistance difference of 10 between the 1 st branch conductive member and the 2 nd branch conductive member³More than times and more than the resistance values of copper and aluminum.

Description

Workpiece holding jig and surface treatment device

Technical Field

The present invention relates to a work holding jig, a surface treatment apparatus, and the like used for surface treatment such as plating.

Background

There is known a continuous plating apparatus for performing plating while continuously conveying a work by suspending the work by a work holding jig and immersing the work in a treatment liquid in a treatment tank (patent documents 1 and 2). The work holding jig holds the work and sets the work as a cathode.

Documents of the prior art

Patent document

Patent document 1: japanese patent No. 5898540

Patent document 2: WO2018/062259

Disclosure of Invention

Problems to be solved by the invention

When the workpiece holding jig supplies current to a plurality of portions of the workpiece through the branched conductive members, if the currents flowing through the branched conductive members to the workpiece are different, the in-plane uniformity of the workpiece subjected to the surface treatment is deteriorated.

The purpose of some aspects of the present invention is to reduce the variation in current flowing through a workpiece and improve the in-plane uniformity of the workpiece subjected to surface treatment.

Means for solving the problems

(1) One aspect of the present invention relates to a work holding jig capable of holding a surface-treated work and electrically connectable to a rectifier that is voltage-controlled so as to flow a constant current, wherein a conductive member capable of electrically connecting the rectifier and the work includes: a common conductive member; and a1 st branch conductive member and a2 nd branch conductive member which branch from the common conductive member and are connected to the workpiece, wherein the common conductive member includes a material having a maximum resistance difference of 10 between the 1 st branch conductive member and the 2 nd branch conductive member³More than times and more than the resistance values of copper and aluminum.

According to one embodiment of the present invention, a rectifier electrically connected to a work holding jig via a power supply portion, for example, a power supply rail, adjusts a voltage E according to a resistance R so as to flow a set constant current I,to achieve E ═ rxi. In one aspect of the present invention, a conductive member electrically connectable to a rectifier and a workpiece includes: a common conductive member; and a1 st branch conductive member and a2 nd branch conductive member branched from the common conductive member and connected to the workpiece. The resistance R of the closed loop system comprises a resistance value R of the common conductive member that is greater than the resistance value of copper or aluminum, which is generally considered to be low resistance. When R is not less than 10, the maximum resistance difference Δ R Ω generated between the 1 st branch conductive member and the 2 nd branch conductive member is³The resistance R of the system including the resistance R of the common conductive member also increases by × Δ R Ω. Therefore, the rectifier adjusts to a relatively large voltage V and supplies a constant current I. In this way, if the current (or electrons) flowing through the 1 st branch conductive member and the 2 nd branch conductive member join together in the common conductive member and the current I can flow at a voltage E that greatly exceeds the deviation voltage Δ V corresponding to the deviation Δ R Ω of the resistance between the 1 st branch conductive member and the 2 nd branch conductive member, the deviation Δ R Ω of the resistance can be ignored. Thus, the maximum resistance difference Δ R Ω generated between the 1 st branch conductive member and the 2 nd branch conductive member can reduce the variation in the current flowing through the workpiece depending on the position in the workpiece, and can improve the in-plane uniformity of the workpiece subjected to the surface treatment. The jig according to one embodiment of the present invention may be continuously conveyed or intermittently conveyed in the processing bath, or may be supported so as to freely move in and out of the processing bath without being conveyed.

(2) In one embodiment (1) of the present invention, the present invention further comprises:

an upper frame disposed above an upper end of the workpiece; and

a plurality of upper clamps which are held by the upper frame and clamp the upper end of the workpiece,

the conducting member includes:

a1 st contact part and a2 nd contact part which are in contact with a power supply rail connected to the rectifier;

a pair of 1 st cables, one end of each of which is electrically connected to the 1 st contact portion and the 2 nd contact portion;

a common connection portion to which the other ends of the pair of 1 st cables are electrically connected in common; and

a pair of 1 st connecting portions for electrically connecting both end portions of the upper frame and the common connecting portion,

the common conductive member may include the common connection portion.

In this way, in the case where the jig is conveyed along the power supply rail in the processing bath, the present invention can also be applied to a jig for electrically connecting the rectifier and the common conductive member by the 1 st contact portion, the 2 nd contact portion, and the pair of 1 st cables.

(3) In one aspect (2) of the present invention,

the common connection portion includes:

a1 st conductive member to which the other ends of the pair of 1 st cables are electrically connected in common; and

a pair of 2 nd conductive members fixed to both end portions of the 1 st conductive member at positions equidistant from a position where the respective other ends of the pair of 1 st cables are electrically connected to the 1 st conductive member in common,

one of the pair of the 2 nd conductive members is electrically connected to the 1 st connecting portion, and the other of the pair of the 2 nd conductive members is electrically connected to the 2 nd connecting portion,

the pair of 2 nd conductive members are respectively formed of the above-mentioned material,

the 1 st conductive member may have a resistance value smaller than that of the material.

In this way, substantially no resistance difference is generated between the conductive path from the 1 st conductive member to one of the pair of 2 nd conductive members and the conductive path from the 1 st conductive member to the other of the pair of 2 nd conductive members, and a large resistance can be added by the material of the pair of 2 nd conductive members.

(4) In the aspect (2) or (3) of the present invention,

one of the pair of 1 st cables may be connected to a surface of the 1 st conductive member, and the other of the pair of 1 st cables may be connected to a rear surface of the 1 st conductive member.

In this way, it is easy to set the distance from the position where one of the pair of 1 st cables is connected to the surface of the 1 st conductive member to one of the pair of 2 nd conductive members, and the distance from the position where the other of the pair of 1 st cables is connected to the back surface of the 1 st conductive member to the other of the pair of 2 nd conductive members to be equal.

(5) In one aspect (2) to (4) of the present invention,

the 1 st branch conductive member may be formed of a member that makes the common connection portion and one of the plurality of upper clips conductive via one of the pair of 1 st connection portions,

the 2 nd branch conductive member may be formed of a member that makes the common connection portion and the other of the plurality of upper clips conductive via the other of the pair of 1 st connection portions.

In this way, the variation in the current flowing through the workpiece due to the maximum resistance difference Δ R Ω between the plurality of upper clamps is reduced, and the in-plane uniformity of the workpiece subjected to the surface treatment can be improved.

(6) In one aspect (2) to (4) of the present invention, the present invention may further include:

a frame body including the upper frame, a lower frame, and a pair of vertical frames connecting the upper frame and the lower frame;

a plurality of lower clamps which are held by the lower frame and clamp the lower end of the workpiece; and

and a pair of 2 nd connecting portions electrically insulated from the upper frame and electrically connecting the pair of vertical frames electrically connected to both end portions of the lower frame and the common connecting portion.

Thus, the present invention can also be applied to a jig having a lower clamp in addition to an upper clamp.

(7) In one aspect (6) of the present invention,

the 1 st branch conductive member may be formed of a member that makes the common connection portion and one of the plurality of lower clips conductive via one of the pair of 2 nd connection portions,

the 2 nd branch conductive member may be formed of a member that makes the common connection portion and the other of the plurality of lower clips conductive via the other of the pair of 2 nd connection portions.

In this way, the variation in the current flowing through the workpiece due to the maximum resistance difference Δ R Ω between the plurality of lower clamps is reduced, and the in-plane uniformity of the workpiece subjected to the surface treatment can be improved.

(8) In the aspect (6) or (7) of the present invention,

the pair of the first connecting portions 1 includes a pair of metal plates,

the pair of 2 nd connecting parts comprise a pair of 2 nd cables,

the resistance value from the common connection portion to the upper clip may be larger than the resistance value from the common connection portion to the lower clip.

In this way, as compared with the upper clamp in which only the tip portion is immersed in the treatment liquid, it is possible to cause the lower clamp immersed in the treatment liquid as a whole to flow as much current as the current consumed for the surface treatment of the workpiece through the lower clamp. As a result, the in-plane uniformity of the surface-treated workpiece can be improved.

(9) In one aspect (1) to (8) of the present invention,

the maximum resistance difference can be 10-20 m omega. In this case, the common connection portion has a resistance value of 10 to 20 Ω or more, and can be made of a material having a resistance value larger than that of low-resistance copper or aluminum of several Ω.

(10) In one embodiment (1) to (9) of the present invention,

the material can be stainless steel or titanium. The resistance value of stainless steel or titanium is an order of magnitude larger than that of copper or aluminum which is generally considered to be low resistance, and a resistance value sufficiently larger than 10 to 20 Ω can be secured.

(11) Another aspect of the present invention relates to a surface treatment apparatus including:

the work holding jig of any one of (1) to (10) above;

a power supply unit connected to the rectifier and in contact with the holding jig; and

and a surface treatment tank including an anode connected to the rectifier.

According to another aspect of the present invention, the in-plane uniformity of the surface-treated workpiece can be improved by the operational effects of the above-described aspects (1) to (10). When the jig is conveyed in the surface treatment tank, the power supply portion provided in the surface treatment apparatus and in contact with the jig is used as a power supply rail. In the case where the jig is not transferred, the power supply portion may be a fixed contact point that is in contact with the conductive member of the jig.

Drawings

Fig. 1 is a longitudinal sectional view of a surface treatment apparatus according to an embodiment of the present invention.

Fig. 2 is a partially enlarged view of fig. 1.

Fig. 3 is a side view of the workpiece holding jig as viewed from the conveying direction.

Fig. 4 is a diagram showing a support structure provided to a contact portion of the work holding jig.

Fig. 5 is a front view of the work holding jig.

Fig. 6 is a diagram schematically showing a jig of a comparative example.

Fig. 7 is a characteristic diagram showing a comparative example of the current flowing through the jig in fig. 6.

Fig. 8 is a diagram schematically showing a jig of an embodiment of the present invention.

Fig. 9 is a characteristic diagram of the present embodiment showing the current flowing through the jig in fig. 8.

Fig. 10 is an enlarged view of the upper dummy plate and the insulating plate.

Fig. 11 is a side view of an upper dummy plate.

Fig. 12 is a diagram showing that the upper dummy plate is movable between the 1 st position and the 2 nd position.

Fig. 13 is a diagram showing a dummy plate and an adjustment member provided to the lower clip.

Fig. 14 is a plan view showing a state in which the adjustment member is superimposed on the dummy plate.

Fig. 15 is a view from direction D-D of fig. 5.

Fig. 16 is a front view of the 1 st side dummy member.

Fig. 17 is a diagram illustrating upper support structures of the 1 st side dummy member and the 2 nd side dummy member.

Fig. 18 is a top view of an upper support structure of a1 st side dummy member and a2 nd side dummy member.

Fig. 19 is a diagram illustrating lower support structures of the 1 st side dummy member and the 2 nd side dummy member.

Detailed Description

In the following disclosure, a number of different implementations and embodiments are provided for implementing different features of the claimed subject matter. Of course, these are merely examples and are not intended to be limiting. Further, in the present disclosure, reference numbers and/or letters are sometimes repeated in various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. Further, when the 1 st element is described as being "connected" or "coupled" to the 2 nd element, such description includes an embodiment in which the 1 st element and the 2 nd element are directly connected or coupled to each other, and also includes an embodiment in which the 1 st element and the 2 nd element are indirectly connected or coupled to each other with 1 or more other elements interposed therebetween. In addition, when a1 st element is described as "moving" relative to a2 nd element, such description includes embodiments in which at least one of the 1 st element and the 2 nd element moves relative to the other.

1. Outline of surface treatment apparatus

FIG. 1 is a longitudinal sectional view of a surface treatment apparatus, for example, a continuous plating apparatus. In the continuous plating apparatus 10, a plurality of conveyance jigs 30 each holding a workpiece 20 such as a circuit board are circularly conveyed in a direction perpendicular to the paper surface of fig. 1. In fig. 1, 2 parallel

straight conveyance paths

110, 120 among the endless conveyance path 100 are shown. The 2

linear transport paths

110 and 120 are connected at both ends to form an endless circulating transport path 100.

The circulating transport path 100 is provided with: a plating tank (broadly, a surface treatment tank) 200 for performing a surface treatment, for example, a plating treatment, on the workpieces 20 held by the plurality of workpiece holding jigs 30; a carrying-in section (not shown) for carrying the unprocessed workpieces 20 into the plurality of conveyance jigs 30; and a carry-out section (not shown) for carrying out the processed workpiece 20 from the plurality of workpiece holding jigs 30.

In the present embodiment, the plating tank 200 is provided along the 2 nd linear transport path 120, and the carrying-in part and the carrying-out part are provided on the 1 st linear transport path 110. The endless transfer path 100 further includes: a pretreatment tank group 230 disposed upstream of the plating tank 200; and a post-treatment bath group (not shown) disposed downstream of the plating bath 200.

As shown in fig. 1, the continuous plating treatment apparatus 10 has a plating tank (broadly, a surface treatment tank) 200 that contains a plating liquid (broadly, a treatment liquid) and has an upper end opening 201. As shown in fig. 2, which is an enlarged view of a part of fig. 1, the continuous plating apparatus 10 further includes at least 1, for example, 21 st guide rails 130 and 2 nd guide rails 140 extending in the 1 st direction (direction perpendicular to the paper plane) parallel to the longitudinal direction of the plating tank 200 at positions offset above the upper end opening 201 of the plating tank 200. The plurality of conveyance jigs 30 are disposed in the processing liquid of the plating tank 200 to hold the workpieces 20, respectively, and are supported by the 1 st guide rail 130 and the 2 nd guide rail 140.

As shown in fig. 3, each of the plurality of work holding jigs 30 has a conveying portion 300 and a work holding portion 500 substantially separately. The conveying unit 300 includes a horizontal arm 301, a1 st guided portion 310, and a2 nd guided portion 320. The 1 st guided portion 310 is supported by one end side of the horizontal arm portion 301, and is guided by the 1 st guide rail 130. The 2 nd guided portion 320 is supported by the other end side of the horizontal arm portion 301 and guided by the 2 nd guide rail 140. The 1 st guided portion 310 includes:

rollers

311, 312, 313 rotatably contacting the upper surface and both side surfaces of the 1 st guide rail 130. The 2 nd guided portion 320 includes: and a roller 321 rotatably contacting an upper surface of the 2 nd guide rail 140.

In the plating apparatus 10, the workpiece 20 is used as a cathode (cathode), and the plating tank 200 is provided with

anode tanks

202 and 203 for accommodating anodes (anode)410L and 410R on both sides of the conveyance path with the workpiece 20 interposed therebetween. An electric field is formed between the cathode and the anode by a rectifier, not shown, and the plating solution is electrolyzed to plate the work 20. For this reason, the work 20 in conveyance needs to be energized. For supplying power to the workpiece 20, a power supply portion, for example, a power supply rail 210 is provided. In particular, in order to implement the current control method disclosed in japanese patent application laid-open No. 2009-132999, as shown in fig. 2, the power supply rail 210 of the present embodiment has a plurality of, for example, 4 divided power supply rails 210A to 210D insulated from each other. Each of the plurality of workpiece holding jigs 30 has a power supply receiving portion 340 (fig. 2 and 3) that contacts any of the 4 divided power supply rails 210A to 210D to supply power.

Fig. 4 shows details of the supplied power part 340. The power receiving portion 340 has a conductive contact portion (collector) 341 that contacts the power supply rail 210 in the support plate 330 fixed to the horizontal arm portion 301. The contact portion 341 is linked to the support plate 330 by a parallel link mechanism 342 having 2

parallel links

342A, 342B. The 2

links

342A, 342B are biased to move in the clockwise direction by torsion coil springs 343, 343 as biasing members. As a result, the contact portion 341 can be brought into contact with the power supply rail 210 with an appropriate contact pressure.

In addition, the 2

parallel links

342A, 342B are inclined with respect to the conveying direction a of the jig 30 such that the upper fulcrum is behind the front and lower fulcrums. As a result, the contact portion 341 operates so as to be pulled by the work holding jig 30, and therefore, the operation is stable.

2. Workpiece holding part

As shown in fig. 5, the work holding portion 500 includes: a plurality of conductive upper clamps 510 for clamping the upper edge 20a of the rectangular workpiece 20; a plurality of conductive lower clamps 520 for clamping the lower edge 20b of the rectangular workpiece 20; and a frame 530 disposed so as to surround the rectangular workpiece 20 and supporting the plurality of upper clamps 510 and the plurality of lower clamps 520.

The frame 530 has: a conductive upper frame 531 for supporting the plurality of upper clips 510; a conductive lower frame 532 supporting the plurality of lower clamps 520; and a pair of conductive

vertical frames

533 and 534 connected to both end portions of the upper frame 531 and both end portions of the lower frame 532, respectively. Here, the pair of

vertical frames

533 and 534 are electrically insulated from both end portions of the upper frame 531, and electrically connected to both end portions of the lower frame 532. The upper frame 531 and/or the lower frame 532 are also referred to as support portions of the support clips (the upper side clip 510 and/or the lower side clip 520).

3. Conductive member with workpiece as cathode

In the present embodiment, the conductive member provided in the workpiece holding jig 30 and electrically connectable to the rectifier and the workpiece 20 includes: a1 st branch conductive member and a2 nd branch conductive member; and a common conductive member electrically connected to the 1 st branch conductive member and the 2 nd branch conductive member.

Specifically, as shown in fig. 5, the pair of contact portions 341 are arranged at intervals in the conveying direction a of the workpiece holding jig 30. The contact portion 341 on the upstream side in the transport direction a is referred to as a1 st contact portion 341A, and the contact portion 341 on the downstream side in the transport direction a is referred to as a2 nd contact portion 341B. One end of each of the pair of 1

st cables

350A, 350B is electrically connected to the 1 st contact portion 341A, the 2 nd contact portion 341B.

The other ends of the pair of

first cables

350A and 350B are commonly connected to a common connection portion 360. The common connection part 360 as a common conductive member can include: a1 st conductive member 361 for electrically connecting the other ends of the pair of 1

st cables

350A and 350B in common; and a pair of 2 nd

conductive members

362, 363 fixed to both end portions of the 1 st conductive member 361. The pair of 2 nd

conductive members

362 and 363 are fixed to both end portions of the 1 st conductive member 361 at positions equidistant L from the position where the respective other ends of the pair of 1

st cables

350A and 350B are electrically connected to the 1 st conductive member 361 in common. In order to commonly connect the pair of 1 st cables 350A, 350 at a position equidistant L from both end portions of the 1 st conductive member 361, one of the pair of 1 st cables 350A, 350 may be connected to the surface of the 1 st conductive member 361 and the other may be connected to the back surface of the 1 st conductive member 361.

The conductive member provided in the work holding jig 30 further includes: a pair of 1

st connection portions

370A and 370B electrically connecting both end portions of the upper frame 531 and the common connection portion 360; and a pair of 2

nd connection portions

380A and 380B electrically connecting the pair of

vertical frames

533 and 534 electrically connected to both end portions of the lower frame 532 and the common connection portion 360. The pair of

vertical frames

533 and 534 are electrically insulated from the upper frame 531. The resistance value can be adjusted by adjusting the shape, thickness, material, and the like of the pair of 2

nd connecting portions

380A and 380B, and the current flowing through the upper clip 510 can be adjusted.

The 1 st branch conductive member is formed of a member that makes the common connection portion 360 and one of the plurality of upper side clips 510 conductive via one of the pair of 1

st connection portions

370A, 370B and the upper frame 531. In this case, the 2 nd branch conductive member is formed of a member that makes the common connection portion 360 and the other of the plurality of upper side clips 510 conductive via the other of the pair of 1

st connection portions

370A, 370B and the upper frame 531.

Alternatively, the 1 st branch conductive member is formed of a member that makes the common connection portion 360 and one of the plurality of lower clips 520 conductive via one of the pair of 2

nd connection portions

380A, 380B, one of the pair of

vertical frames

533, 534, and the lower frame 532. In this case, the 2 nd branch conductive member is formed of a member that makes the common connection portion 360 and the other of the plurality of lower clips 520 conductive via the other of the pair of 2

nd connection portions

380A, 380B, the other of the pair of

vertical frames

533, 534, and the lower frame 532.

Here, the common connection portion 360 as the common conductive member includes a high resistance material having a resistance value R of 10 of the maximum resistance difference Δ R Ω between the 1 st branch conductive member and the 2 nd branch conductive member³More than twice the resistance value, and is greater than the resistance values of copper and aluminum. In the present embodiment, in the common connection portion 360, the pair of 2 nd

conductive members

362 and 363 are formed of a high-resistance material, and the 1 st conductive member 361 is formed of a low-resistance member.

Examples of the high-resistance material include stainless steel (SUS). For example, SUS304 has a volume resistivity (Ω · m) of 73.7, which is an order of magnitude larger than 1.7 Ω · m for copper and 2.8 Ω · m for aluminum. The measured maximum resistance difference DeltaR omega is 10-20 m omega, so the resistance value R of the high-resistance material satisfies the condition that R is more than or equal to DeltaR multiplied by 10³. Similarly, for example, 53.3 Ω · m titanium is also suitable as the high-resistance material.

Here, in order to allow the set constant current I to flow through the rectifier electrically connected to the work holding jig 30 via the power supply rail 210, the voltage E is adjusted so as to be equal to R × I in accordance with the impedance Z of the closed loop system of the current path. In the present embodiment, the resistance R of the closed loop system includes a high resistance value R of the pair of 2 nd conductive members as the common conductive member, which is larger than a copper or aluminum resistance value that is generally considered to be a low resistance. When r.gtoreq.10 is equal to or greater than the maximum resistance difference Δ R Ω generated between the 1 st branch conductive member and the 2 nd branch conductive member (i.e., between the upper clips 510 or between the lower clips 520)³The resistance R of the system including the resistance R also increases by ×. Δ R Ω. Therefore, the rectifier adjusts to a relatively large voltage V and supplies a constant current I. Thus, flow ofThe currents (or electrons) of the 1 st branch conductive member and the 2 nd branch conductive member are merged at the common connection portion 360, and if the current I can flow at a voltage E that greatly exceeds the deviation voltage Δ V corresponding to the deviation Δ R Ω of the resistance between the 1 st branch conductive member and the 2 nd branch conductive member, the deviation Δ R Ω of the resistance can be ignored.

3.1. Current monitor of comparative example

Fig. 6 schematically shows a jig of a comparative example in which the common connection portion 360 does not contain a material having a high resistance value r as in the present embodiment. The current flowing through the contact portion on the upstream side in the conveyance direction a of the jig of the comparative example in fig. 6 is a1, and the current flowing through the contact portion on the downstream side in the conveyance direction a is a 2.

In the measurement shown in fig. 7, the set current of the rectifier was 204A (a 1+ a2), and the branch set currents (a1 and a2) flowing in 2 branches were 102A. The currents a1 and a2 measured while the work holding jig is conveyed in the conveying direction a of fig. 6 fluctuate with respect to the branch set current value as shown in fig. 7. Before and after times T1 and T2, as disclosed in japanese patent application laid-open No. 2009-132999, since the jig is transferred from one power supply rail to the other power supply rail through the joint between the power supply rails, control is performed by the rectifier so that the current value of the contact portion with the one power supply rail gradually decreases and the current value of the contact portion with the other power supply rail gradually increases. In a section other than the current taper/taper control, the rectifier controls the output in accordance with the set current. However, the currents a1 and a2 in the comparative example shown in fig. 7 fluctuate little by little in the constant current control section, and fluctuate greatly under the current gradually decreasing/gradually increasing control.

3.2. Current monitor of the present embodiment

Fig. 8 schematically shows the jig 30 of the present embodiment in which the common connection portion 360 contains a material having a high resistance value r. The current flowing through the contact portion 341A on the upstream side in the conveyance direction a of the jig 30 in fig. 8 is a1, the current flowing through the contact portion 341B on the downstream side in the conveyance direction a is a2, the currents flowing through the pair of 1

st connection portions

370A, 370B are A3, a4, and the currents flowing through the pair of 2

nd connection portions

380A, 380B are a5, a 6.

In the measurement shown in fig. 9, the set current of the rectifier was 131A (a 1+ a2), and the branch set currents (a1 and a2) flowing in 2 branches were 65.5A. Before and after the time T, the current decrease/increase control is performed in the same manner as at the times T1 and T2 shown in fig. 7, and the output control is performed in the other section in accordance with the set current. As shown in fig. 9, the currents A3 to a6 measured while the work holding jig 30 is conveyed in the conveying direction a of fig. 8 are constant branch currents A3 and a4 flowing from the left and right of the jig 30 to the upper clamp 510, and constant branch currents a5 and a6 flowing from the left and right of the jig 30 to the lower clamp 520.

In the present embodiment, a difference in resistance due to a variation in contact resistance of the 1 st contact portion 341A and the 2 nd contact portion 341B caused by local dirt or the like of the power supply rail 210 and a difference in resistance during continuous loading of the power supply rail 210 exist in the conduction path between the rectifier and the common connection portion 360, but these adverse effects can be reduced by providing the common connection portion 360 having the above-described resistance value.

In the present embodiment, the pair of 1 st connection portions may include the pair of

metal plates

370A, 370B, and the pair of 2 nd connection portions may include the pair of 2

nd cables

380A, 380B. In this way, the resistance value from the common connection portion 360 to the upper clip 510 can be made larger than the resistance value from the common connection portion 360 to the lower clip 520.

As described above, compared to the upper clamp 510 in which only the tip portion is immersed in the treatment liquid, it is possible to cause the lower clamp 520 immersed in the treatment liquid as much as the current consumed for the surface treatment of the lower clamp 520 to flow to the workpiece through the lower clamp 520. In fig. 9, currents a5 and a6 flowing through the lower clamp 520 are made larger than currents A3 and a4 flowing through the upper clamp 510, and as a result, currents flowing from above and below to the workpiece 20 can be made substantially constant.

4. Upper dummy plate/lower dummy plate

As shown in fig. 5, when the upper frame 531 and/or the lower frame 532 are used as the conductive support portions, the support portions may include the conductive upper dummy plate 610 and/or the conductive lower dummy plate 620 in addition to the upper clip 510 and/or the lower clip 520. The upper dummy plate 610 is disposed in the upper edge 20a of the workpiece 20 in a region not held by the upper clamp 510, close to the upper edge 20a of the workpiece 20. The lower dummy plate 620 is disposed in the lower edge portion 20b of the workpiece 20 in a region not held by the lower clamp 520, close to the lower edge portion 20b of the workpiece 20.

The upper dummy plate 610 and the conductive lower dummy plate 620 are each movably supported on at least one surface, for example, the front and back surfaces, to cover the front and back surfaces, respectively, and can have an insulating plate 630 adjusting exposed conductive areas of the

dummy plates

610, 620, respectively.

Fig. 10 is an enlarged view of the upper dummy plate 610. The lower dummy plate 620 also adopts the structure shown in fig. 10. As shown in fig. 10, the upper dummy plate 610 is fixed to the upper frame 351 by, for example, screws 612 via hinges 611 formed integrally with or separately from the upper dummy plate 610. The insulating plate 630 covering both surfaces of the upper dummy plate 610 may have either one or both of an insulating plate 630A covering the surface of the upper dummy plate 610 and an insulating plate 630B covering the back surface of the upper dummy plate 610. The insulating plates 620A and 620B are fastened to, for example, the upper dummy plate 610 by bolts 641 inserted through long holes 631A and 631B (only the long hole 631A is shown in fig. 10) provided in the longitudinal directions of the insulating

plates

630A and 630B, respectively, and holes 612 provided in the upper dummy plate 610, and nuts 642 screwed into the bolts 641.

The insulating plates 620A and 620B can be adjusted in vertical position with respect to the upper dummy plate 610 (lower dummy plate 620) within the range of the elongated holes 631A and 631B, respectively. As a result, as shown in fig. 10, the exposed area S of the conductive surface exposed by the front end portion 610A of the upper dummy plate 610 can be independently adjusted on the front surface and the back surface. By changing the exposed conductive area S of the upper dummy plate 610, the current consumed for the surface treatment of the upper dummy plate 610 can be adjusted. Thereby, the current flowing to the upper edge portion 20a of the workpiece 20 via the upper clamp 510 can be adjusted. Thus, the current flowing through the upper edge portion 20a of the workpiece 20 can be adjusted, and the in-plane uniformity of the workpiece subjected to the surface treatment can be improved. By adjusting the lower dummy plate 620 in the same manner, the current flowing through the lower edge portion 20b of the workpiece 20 can be adjusted, and the in-plane uniformity of the surface-treated workpiece can be improved.

The upper dummy plate 610 can be bent by the hinge 611 between the 1 st position P1 shown by a solid line and the 2 nd position P2 shown by a chain line in fig. 12. At the 1 st position P1, the upper dummy plate 610 is disposed in parallel with the workpiece 20 near the region of the upper edge portion 20a of the workpiece 20 that is not held by the upper clamp 510. In the 2 nd position P2, the upper dummy plate 610 is not parallel to the major surface of the workpiece 20, for example, intersects the major surface of the workpiece 20 at a right angle.

When the workpiece 20 is surface-treated, the upper dummy plate 610 is set at the 1 st position P1. On the other hand, when the workpiece 20 is loaded and unloaded to and from the workpiece holding jig 30 by the robot, the upper dummy plate 610 is set at the 2 nd position P2. By setting the upper dummy plate 610 at the 2 nd position P2, a gap can be secured between the upper edge portion 20a of the workpiece 20 and the upper frame 351. This enables the upper edge portion of the workpiece 20 to be clamped by the robot at a position different from the upper clamp 510 of the workpiece holding jig 30. In this case, the upper dummy plate 610 may be pushed by a robot to move the upper dummy plate 610 from the 1 st position P1 to the 2 nd position P2 in the direction of arrow F1. For example, as shown in fig. 12, the upper dummy plate 610 may be pushed by a roller 1100 provided at the front end of an arm 1000 that moves and is automated. Similarly, the lower dummy plate 620 may be bent between the 1 st position P1 and the 2 nd position P2.

The upper dummy plate 610 may be moved and biased to the 1 st position P1 by elasticity of the hinge 611 itself or a biasing member such as a leaf spring or a coil spring provided to the hinge 611. Thus, the upper dummy plate 610 can be reset from the 2 nd position P2 to the 1 st position P1 in the direction of the arrow F2 without applying a reset external force. Similarly, the lower dummy plate 620 may be reset from the 2 nd position P2 to the 1 st position P1 in the direction of arrow F2 without applying a reset external force.

In the case where the workpiece holding jig has upper, lower, left, and right clamps for clamping four sides of the rectangular workpiece 20, the dummy plates and the insulating plates may be disposed in the four sides of the workpiece holding jig.

5. Dummy plate and adjustment member for clip

Next, a dummy plate and an adjustment member provided in one or both of the upper clamp 510 and the lower clamp 520 will be described by taking the lower clamp 520 as an example. The dummy plate and the adjustment member provided in the upper clip 510 can be understood by changing "the lower clip 520" to "the upper clip 510" and "the lower frame 532" to "the upper frame 531" in the following description.

Fig. 13 shows a dummy plate 700 and an adjustment member 720 provided to the lower clip 520. First, the lower clip 520 includes: a fixing portion 521 fixed to the lower frame 532; and a movable portion 523 supported swingably with respect to the fixed portion 521. The fixing portion 521 has a1 st surface 521A and a2 nd surface 521B opposite thereto. In the fixing portion 521, the 2 nd surface 521B is in surface contact with the lower frame 532, and is fixed to the lower frame 532 by the bolt 522. The fixing portion 521 has 2 side walls 521C vertically standing from the 1 st surface 521A.

The lower edge portion 20b of the workpiece 20 is partially held between the movable portion 523 that swings and the 1 st surface 521A of the fixed portion 521. The movable portion 523 is swingable around a pin 524 supported by the 2 side walls 521C of the fixed portion 521. A coil spring 525 is inserted through the pin 524. The movable portion 523 is moved and biased by the coil spring 525 so as to face the fixed portion 521. The movable portion 523 is electrically connected to the lower frame 532 via the fixed portion 521, the pin 524, or the coil spring 525. In order to reduce the resistance value of the conductive path, the coil spring 525 may be changed to a plate spring or the like.

The conductive dummy plate 700 includes: a3 rd surface 700A facing the 2 nd surface 521B of the fixing portion 521; and a4 th surface 700B opposite to the 3 rd surface 700A. One end of the dummy plate 700 is referred to as a base end 701, and the other end is referred to as a tip end 704. In the dummy plate 700, the 4 th surface 700B is parallel to the 2 nd surface 521B of the fixing portion 521, and the base end portion 701 is supported by the fixing portion 521.

Here, as shown in fig. 14, for example, 2

long holes

702 and 703 can be formed in the base end portion 701 of the dummy plate 700. A bolt 710 is inserted into each of the

elongated holes

702 and 703, and the bolt 710 is fastened to the lower frame 532. The fixed position of the dummy plate 700 can be adjusted in the direction of arrow C in fig. 13 by the

elongated holes

702 and 703.

As shown in fig. 13 and 14, the insulating adjustment member 720 covers a part of the 4 th surface 700B of the dummy plate 700 and overlaps the dummy plate 700. The conductive surface that is not always covered by the adjustment member 720 may be only the front end portion 704. As shown by hatching in fig. 13 and 14, the other surface not covered with the adjustment member 720 is subjected to insulation coating.

As shown in fig. 14, for example, 2

long holes

721 and 722 are formed in the adjustment member 720. A bolt 730 is inserted into each of the

elongated holes

721 and 722, and the bolt 730 is fastened to the dummy plate 700. The adjustment member 720 can adjust the fixed position in the arrow C direction of fig. 13 by the

elongated holes

702 and 703. Thus, the adjustment member 720 can adjust the exposed conductive area S2 on the 4 th surface 700B side in the front end portion 704 of the dummy plate 700.

The exposed conductive surface on the 4 th surface 700B side in the front end 704 of the dummy plate 700 is subjected to surface treatment. By changing the exposed conductive area S2 of the dummy plate 700, the current consumed for the surface treatment of the dummy plate 700 can be adjusted. Thereby, the current flowing to the lower edge portion 20b of the workpiece 20 via the fixing portion 521 of the lower clamp 520 can be adjusted. If the dummy plate 700 and the adjustment member 720 are not provided, the current flowing to the lower edge portion 20b of the workpiece 20 through the fixing portion 521 of the lower clamp 520 increases. This is because, as described above, the resistance value between the movable portion 523 and the lower frame 532 is relatively large. Thus, the current does not concentrate on the lower edge portion 20b of the workpiece 20 near the region in contact with the movable portion 523 and the surface 20b1 on the side in contact with the movable portion 523 (fig. 13). On the other hand, the current tends to concentrate more on the lower edge portion 20b of the workpiece 20 near the region in contact with the fixed portion 521 and the face 20b2 on the side in contact with the fixed portion 521 (fig. 13). As a result, the surface treatment of the workpiece 20 is locally performed in the region near the fixed portion 521. According to the present embodiment, the current flowing through the local region 20b2 of the lower edge portion 20b of the workpiece 20 can be adjusted, and the in-plane uniformity of the workpiece subjected to the surface treatment can be improved.

Further, the fixing position of the base end part 701 of the dummy plate 700 to the fixing part 521 can be changed in the direction parallel to the arrow C direction in which the adjustment member 720 is movable by the

elongated holes

702 and 703. In this way, in a side view viewed from a direction orthogonal to the main surface of the workpiece 20, the overlapping area of the 2 nd surface 521B of the fixing portion 521 of the lower clamp 520 or the main surface of the workpiece and the dummy plate 700 can be adjusted. By this position adjustment, the current consumed for the surface treatment of the dummy plate 700 can also be adjusted.

Here, the liquid level L shown in fig. 5 is set for the treatment liquid Q in the treatment tank 200 shown in fig. 1 with respect to the jig 30. Thereby, the entire lower clamp 520 is immersed in the treatment liquid Q. Therefore, in the dummy plate 700, except for the 4 th surface 700B in the front end portion 704, the other surfaces not covered with the alignment member 720 are subjected to insulation coating as shown by hatching in fig. 13 and 14. Thus, the surface of the front end 704 of the dummy plate 700 other than the 4 th surface 700B is not unnecessarily surface-treated.

The above-described structure of the dummy plate 700 and the adjustment member 720 provided in the lower clip 520 can be applied to the dummy plate and the adjustment member provided in the upper clip 510. The entire upper clamp 510 is different from the lower clamp 520 in that it does not sink into the processing liquid Q from the position of the liquid surface L of the processing liquid Q shown in fig. 5. Therefore, the dummy plate provided in the upper clamp 510 can reduce the insulating coating area only in the area submerged in the processing liquid Q. This is because the region not immersed in the treatment liquid Q is not subjected to surface treatment, and therefore, insulation coating is not required.

6. No. 1 side dummy member and No. 2 side dummy member

As shown in fig. 5, the workpiece holding jig 30 may further include conductive 1 st and 2

nd dummy members

800A and 800B disposed close to both side edge portions of the workpiece 20. As shown in fig. 15, which is a view taken along direction D-D of fig. 5, the 1 st dummy member 800A is disposed between the side edge 20D of the workpiece 20 and the vertical frame 534. The 2 nd dummy member 800B is disposed between the side edge 20c of the workpiece 20 and the vertical frame 534.

Here, the 1 st branch conductive member electrically connected to the 2 nd conductive member 362 of the common conductive member 360, branched from the common conductive member 360, and conductive with the workpiece 20 via the upper side clip 510 is defined by a pair of 1

st connection portions

370A, 370B and an upper frame 531 connected to both end portions thereof. The workpiece holding jig 30 further includes a2 nd branch conductive member 900(900A, 900B) electrically connected to the common conductive member 360, branched from the common conductive member 360, and electrically connected to the 1 st side dummy member 800A and the 2 nd side dummy member 800B. The 1 st dummy conductive member 900A of the 2 nd branch conductive member 900 is branched from the common conductive member 360 and is in conductive communication with the 1 st dummy member 800A. The 2 nd dummy conductive member 900B of the 2 nd branch conductive member 900 branches from the common conductive member 360 and is in conductive communication with the 2 nd side dummy member 800B.

The common conductive member 360 electrically connectable to the rectifier is electrically connected to the workpiece 20 through the upper clamp 510 via the 1 st branch

conductive members

370A, 370B, and 531. The common conductive member 360 is electrically connected to the 1 st side dummy member 800A and the 2 nd side dummy member 800B via the 2 nd branch conductive member 900(900A, 900B). The total current flowing to the workpiece 20, the 1 st side dummy member 800A, and the 2 nd side dummy member 800B may be set by the rectifier. Here, the

vertical frames

533, 534 are subjected to insulation coating. Without the 1 st and 2

nd dummy members

800A, 800B, the electric field concentrates on both side edge portions 20c, 20d of the workpiece 20, and the current flowing to both side edge portions 20c, 20d of the workpiece 20 increases. When the

vertical frames

533 and 534 are not coated with the insulating coating, the current consumption is reduced in order to plate the conductive

vertical frames

533 and 534, and the current flowing through the both side edge portions 20c and 20d of the workpiece 20 is reduced. Therefore, the 1 st and 2 nd dummy

conductive members

900A and 900B may be provided to adjust the current flowing through both side edge portions 20c and 20d of the workpiece 20. Further, by setting the resistance value of the 2 nd branch conductive member 900(900A, 900B) independently of the 1 st branch

conductive members

370A, 370B, 531, the currents flowing through the 1 st dummy member 800A and the 2 nd dummy member 800B can be set independently of the current flowing through the workpiece 20. Thus, by performing surface treatment also on the 1 st side dummy member and the 2 nd side dummy member disposed close to the side edge portions 20c and 20d of the workpiece 20, it is possible to adjust the current flowing through the side edge portions 20c and 20d of the workpiece 20, and it is possible to improve the in-plane uniformity of the workpiece subjected to surface treatment. In addition, by independently setting the resistance values of the 1 st dummy conductive member 900A and the 2 nd dummy conductive member 900B, the currents flowing through the 1 st dummy member 800A and the 2 nd dummy member 800B can be independently set. This enables adjustment of the current flowing through the one side edge 20c and the other side edge 20d of the workpiece 20.

The 1 st dummy conductive member 900A includes, for example: a cable 910A having one end connected to the 2 nd conductive member 362 of the common conductive member 360; a conductive plate 920A to which the other end of the cable 910A is connected; and a cable 930A having one end connected to the conductive plate and the other end connected to the 1 st side dummy member 800A. The 2 nd dummy conductive member 900B similarly includes a cable 910B, a conductive plate 920B, and a cable 930B.

The 1 st and 2 nd dummy

conductive members

900A and 900B may have a1 st and a2 nd variable resistors. The 1 st variable resistor provided in the 1 st dummy conductive member 900A includes a long hole 921A provided in the conductive plate 920A, and a movable contact portion 922A that moves along the long hole 921A. The long hole 921A has a direction (horizontal direction in fig. 5) in which the distance from the connection portion of the cable 910A is longer as a longitudinal direction. By changing the position of movable contact portion 922A connected to cable 930A, the resistance value can be changed. The 2 nd variable resistor provided in the 2 nd dummy conductive member 900B is similarly constituted by the long hole 921B and the movable contact portion 922B. In this way, by adjusting the resistance value using the 1 st variable resistor and the 2 nd variable resistor, the resistance value of the 1 st dummy conductive member 900A and the resistance value of the 2 nd dummy member 800B can be arbitrarily adjusted within a predetermined range. The positions of the

movable contact portions

922A and 922B can be adjusted manually or automatically.

In this embodiment, as shown in fig. 5, the 1 st dummy conductive member 900A is electrically connected to the upper portion of the 1 st dummy member 800A, and the 2 nd dummy conductive member 900B is electrically connected to the upper portion of the 2 nd dummy member 800B. In this case, as shown in fig. 16, each of the 1 st side dummy member 800A and the 2 nd side dummy member 800B is preferably formed as: the widths W1, W2, W3 parallel to the thickness direction of the workpiece 20 are narrower at the upper part than at the lower part (W1< W2< W3). The width may be changed stepwise or continuously. The upper portions of the 1 st dummy member 800A and the 2 nd dummy member 800B are closer to the rectifier, and thus the upper portions tend to be more surface-treated than the lower portions. Therefore, the upper portions of both side edge portions 20c and 20d of the workpiece 20 tend to be difficult to be surface-treated (the plating thickness tends to be thin). By narrowing the width of the 1 st dummy member 800A and the 2 nd dummy member 800B at the upper portions, the upper portions of both side edge portions 20c and 20d of the workpiece 20 can be easily surface-treated, and the plating thickness can be secured at the upper portions. This enables the current flowing from the upper portion to the lower portion to be effectively adjusted at both side edge portions of the workpiece 20.

The 1 st and 2 nd dummy supports provided in the workpiece holding jig 30 will be described with reference to fig. 17 to 19. In fig. 17 to 19, the 1 st side dummy support portion and the 2 nd side dummy support portion can be changed in the direction of arrow E, which is the width direction of the workpiece 20, and in the direction of arrow F, which is the thickness direction of the workpiece 20, by the 1 st side dummy member 800A and the 2 nd side dummy member 800B, as shown in fig. 15, for example.

Fig. 17 and 18 are front and top views of a support portion supporting the upper portion of the 1 st side dummy member 800A. The vertical frame 534 is provided at its upper portion with 2 attachment pieces 820A extending inward of the work holding jig 30. An upper support piece 830A supporting the upper portion of the 1 st dummy member 800A is disposed between the 2 mounting pieces 820A. The 2 mounting pieces 820A have long holes 821 whose longitudinal directions are the arrow E directions. A bolt 835 inserted through the elongated hole 821 is screwed into the upper support piece 830A. When the bolts 835 are loosened, the upper support piece 830A can move in the arrow E direction together with the 1 st-side dummy member 800A. When the bolts 835 are tightened, the upper support piece 830A is fixed by 2 mounting pieces 820A.

As shown in fig. 18, the upper support piece 830A has a long hole 831 penetrating vertically and having a longitudinal direction indicated by an arrow F. A bolt 810 inserted through the long hole 831 is screwed into the upper portion of the 1 st dummy member 800A. When the bolts 810 are loosened, the 1 st dummy member 800A can move in the arrow F direction. When the bolts 810A are tightened, the 1 st dummy member 800A is fixed by the upper support plate 830A. Although not shown, the upper portion of the 2 nd dummy member 800B is also supported in the same manner as the upper portion of the 1 st dummy member 800A.

Fig. 19 shows a support portion supporting the lower portion of the 1 st side dummy member 800A. The vertical frame 534 is provided at its upper portion with 2 attachment pieces 820A extending inward of the work holding jig 30. A lower support piece 830B supporting a lower portion of the 1 st side dummy member 800A is disposed between the 2 mounting pieces 820A. The lower support piece 830B has the same structure as the upper support piece 830A except for a structure for supporting the connection portion 850 described later. In addition, the lower portion of the 2 nd side dummy member 800B is also supported in the same manner as the lower portion of the 1 st side dummy member 800A.

For example, the 1 st and 2 nd

side dummy members

800A and 800B can be connected to the rectifier by connecting the

cables

930A and 930B to the bolt 810 shown in fig. 18. The mounting piece 820A and/or the upper support piece 830A and the lower support piece 830B are formed of an insulator so as to electrically insulate the 1 st dummy member 800A and the 2 nd dummy member 800B from the vertical frames 933, 934.

By moving the 1 st and 2

nd dummy members

800A, 800B in the width direction E of the workpiece 20, the surface treatment amount (plating thickness) of the workpiece can be adjusted at both side edge portions 20c, 20d of the workpiece. For example, when the 1 st dummy member 800A is moved to the left side in fig. 15, the plating thickness of the side edge portion 20d of the workpiece 20 can be reduced. On the other hand, when the 1 st dummy member 800A is moved to the right side of fig. 15, the plating thickness of the side edge portion 20d of the workpiece 20 can be increased. Thus, the 1 st and 2

nd dummy members

800A and 800B may be moved only in the width direction E of the workpiece 20.

By moving the 1 st and 2

nd dummy members

800A, 800B in the thickness direction F of the workpiece 20, the surface treatment amounts (plating thicknesses) of the front surface 20d1 and the back surface 20d2 of the workpiece 20 shown in fig. 15 can be adjusted at the both side edge portions 20c, 20d of the workpiece 20, respectively. For example, when the 1 st dummy member 800A is moved upward in fig. 15, the plating thickness of the front surface 20d1 of the workpiece 20 can be reduced. On the other hand, when the 1 st dummy member 800A is moved downward in fig. 15, the plating film thickness of the rear surface 20d2 of the workpiece 20 can be reduced. Thus, the 1 st dummy member 800A and the 2 nd dummy member 800B may be moved only in the thickness direction F of the workpiece 20.

As shown in fig. 19, a connection member 850 for electrically connecting the lower portion of the 1 st side dummy member 800A and the lower portion of the 2 nd side dummy member 800B may be further provided. By providing the connecting member 850, the current is also easily flowed to the lower portions of the 1 st dummy member 800A and the 2 nd dummy member 800B, and the current flowing from the upper portion to the lower portion can be effectively adjusted at both side edge portions 20c and 20d of the workpiece 20.

Both end portions of the connecting member 850 are slidably supported by, for example, 2 lower support pieces 830B shown in fig. 19. Thereby, the 2 lower supporting pieces 830B are allowed to move in the arrow E direction shown in fig. 15. In addition, both end portions of the connection member 850 are electrically connected to the lower portions of the 1 st and 2 nd

side dummy members

800A and 800B through flexible conductive members. This allows the 1 st and 2

nd dummy members

800A and 800B to move in the direction of arrow E, F shown in fig. 15.

Description of the symbols

20 … workpiece, 20A … upper edge portion, 20B … lower edge portion, 20c, 20d … side edge portion, 30 … workpiece holding jig, 210 … power supply portion (power supply rail), 341A, 341B … 1 st contact portion, 2 nd contact portion, 341A, 350A … 1 st branch conductive member, 341B, 350B … 2 nd branch conductive member, 350A, 350B … pair of 1 st cables, 360 … common connection portion (common conductive member), 361 … st 1 st conductive member, 362, 363 … pair of 2 nd conductive members, 370A, 370B … pair of 1 st connection portions (pair of metal plates), 370A, 370B, 531 … th branch conductive member, 380A, 380B … pair of 2 nd connection portions (pair of 2 nd cables), 380A, 380B, 533, 534 … th branch conductive member, 410R, 410L … anode, 510B … upper side clamp, 520B 395 lower side clamp, … a 521, … a fixing portion, 5731 st branch conductive member, 380A, 521B, and 350B 6327 th branch conductive member, 521B … nd surface, 523 … movable portion, 530 … frame body, 531 … upper frame (support portion), 532 … lower frame (support portion), 533, 534 … pair of vertical frames, 610 … upper dummy plate, 620 … lower dummy plate, 611 … hinge, 630A, 630B … insulating plate (upper insulating plate, lower insulating plate, front side insulating plate, back side insulating plate), 700 … dummy plate, 700A … rd surface, 700B … th surface, 701 … base end portion, 704 … tip portion, 720 … adjustment member, 800A 465 th 1 st side dummy member, 800B … nd 2 side dummy member, 850 … connection member, 900(900A, 900B) … nd 2 nd branch conduction member, 900A (910A, 920A, 922A, 930A) … th 1 st conduction member, 900B (910B, 920B, 922B, 930B) … nd 2 nd conduction member, 920A, … th variable resistor, 920B, 921B, 922B … the 2 nd variable resistor, P1 … the 1 st position, P2 … the 2 nd position, S, S2 … exposing a conductive area

Claims

1. A work holding jig capable of holding a work subjected to surface treatment and electrically connectable to a rectifier voltage-controlled so as to pass a constant current, the work holding jig characterized in that,

an electrically conductive member electrically connectable with the rectifier and the workpiece includes: a common conductive member; and a1 st branch conductive member and a2 nd branch conductive member which branch from the common conductive member and are connected to the workpiece,

the common conductive member comprises a material having a maximum resistance difference of 10 between the 1 st branch conductive member and the 2 nd branch conductive member³More than times and more than the resistance values of copper and aluminum.

2. The workpiece holding jig as set forth in claim 1, further comprising:

an upper frame disposed above an upper end of the workpiece; and

a plurality of upper clamps held by the upper frame and clamping an upper end portion of the workpiece,

the conductive member has:

a1 st contact, a2 nd contact, which are in contact with a supply rail connected to the rectifier;

a pair of 1 st cables, each of one ends of which is electrically connected to the 1 st contact part and the 2 nd contact part;

a pair of 1 st connection portions electrically connecting both end portions of the upper frame and the common connection portion,

the common conductive member includes the common connection portion.

3. The workpiece holding jig of claim 2,

the common connection portion includes:

a pair of 2 nd conductive members fixed to both end portions of the 1 st conductive member at positions equidistant from a position where the respective other ends of the pair of 1 st cables are commonly electrically connected to the 1 st conductive member,

one of the pair of 2 nd conductive members is electrically connected to the 1 st connection portion, and the other of the pair of 2 nd conductive members is electrically connected to the 2 nd connection portion,

the pair of 2 nd conductive members are respectively formed of the material,

the 1 st conductive member has a resistance value less than the material.

4. The workpiece holding jig according to claim 2 or 3, wherein one of the pair of 1 st electric cables is connected to a surface of the 1 st conductive member, and the other of the pair of 1 st electric cables is connected to a back surface of the 1 st conductive member.

5. The work holding jig according to any one of claims 2 to 4,

the 1 st branch conductive member is formed of a member that makes the common connection portion and one of the plurality of upper side clips conductive via one of the pair of 1 st connection portions,

the 2 nd branch conductive member is formed of a member that makes the common connection portion and the other of the plurality of upper clips conductive via the other of the pair of 1 st connection portions.

6. The work holding jig according to any one of claims 2 to 4, further comprising:

a plurality of lower clamps held by the lower frame and clamping a lower end portion of the workpiece; and

7. The workpiece holding jig of claim 6,

the 1 st branch conductive member is formed of a member that makes the common connection portion and one of the plurality of lower clips conductive via one of the pair of 2 nd connection portions,

the 2 nd branch conductive member is formed of a member that makes the common connection portion and the other of the plurality of lower clips conductive via the other of the pair of 2 nd connection portions.

8. The workpiece holding jig according to claim 6 or 7,

the pair of 1 st connecting portions includes a pair of metal plates,

the pair of 2 nd connecting parts comprise a pair of 2 nd cables,

the resistance value from the common connection portion to the upper side clip is larger than the resistance value from the common connection portion to the lower side clip.

9. The workpiece holding jig according to any one of claims 1 to 8, wherein the maximum resistance difference is 10m Ω to 20m Ω.

10. A workpiece holding jig as defined in any one of claims 1 to 9 wherein said material is stainless steel or titanium.

11. A surface treatment device, characterized by comprising:

the work holding jig of any one of claims 1 to 10;

a power supply portion connected to the rectifier, in contact with the workpiece holding jig; and

a surface treatment tank having an anode connected to the rectifier.