Gold plating tool and electroplating method for electroplating thick gold layers on miniature parts in batches

Abstract

The invention discloses a gold plating tool and method for electroplating thick gold layers on miniature parts in batches, the gold plating tool comprises an electroplating frame, a gold plating mold for placing miniature plated parts, and a circuit board arranged on a supporting plate of the electroplating frame and matched with the gold plating mold, and the supporting plate and the circuit board are provided with a plurality of through holes I for installing the gold plating mold; corresponding conducting rings are arranged at the through holes I in the circuit board, the conducting ring located in the center of the circuit board is connected with the conducting column on the electroplating frame, and other conducting rings except the conducting ring located in the center of the circuit board are connected with the conducting ring located in the center of the circuit board through wires with the same length and diameter arranged in the circuit board. According to the electroplating tool, when thick gold layers are electroplated on tiny parts in batches, under the condition that the surface quality is not negatively affected, currents flowing through all the electroplated parts tend to be consistent in the electroplating process, the thickness consistency of the gold layers of the parts is guaranteed, and the electroplating tool is simple and compact in structure and convenient to use.

Description

Technical Field

[0001] The invention relates to a gold-plating tool for micro parts, and more specifically, to a gold-plating tool for batch electroplating thick gold layers on micro parts. Background Art

[0002] At present, the conventional electroplating tool known in the art is composed of a sealing structure, a conductive part, a clamp, a rack, and the like. The part of the plated part that does not need to be electroplated is sealed with a sealing structure, the conductive part is connected, and the clamp is placed if necessary, and then placed on the rack according to the plating tank structure, and the rack is connected to a power supply for electroplating. However, this electroplating tool is only suitable for electroplating a thinner coating of micron level on a larger plated part, and it is difficult to electroplate a thicker gold layer (20μm-200μm) on tiny parts and ensure the consistency of the coating thickness; another roller plating method is suitable for electroplating a thinner gold layer on tiny parts (millimeter level), but when electroplating a thicker gold layer, on the one hand, the consistency of the thickness of the parts cannot be guaranteed, and on the other hand, the collision of the parts during roller plating will cause a larger surface roughness, which cannot meet the better surface quality requirements (roughness <100nm).

[0003] In the batch electroplating production of tiny parts, 22 tiny parts are electroplated at the same time. When the gold layer thickness is required to be 100μm, the thickness deviation of each tiny part needs to be ≤±5μm, and the surface roughness of each tiny part needs to be <100nm. The factor affecting the thickness deviation of the 22 parts is the difference in the electroplating current of each tiny part. The factor affecting the difference in electroplating current is the circuit resistance of each tiny part connected to the negative pole of the power supply. There are two factors affecting the electroplating resistance. The first is the resistance difference caused by the different lengths of the wire connected to the negative pole of the power supply due to the different spatial positions of each plated part. The second is that when the electroplated parts rotate at high speed, the contact resistance between the wire and each plated part changes randomly.

[0004] For example, patent No. CN201610753239.5 discloses a gold-plating tool for contacts. During the gold-plating process, the device completes the gold-plating by rotating the plated parts. However, when multiple plated parts are electroplated with a thicker gold layer, the consistency of the current on each plated part is difficult to control, so the consistency of the thickness of the electroplated layer on the surface of the plated parts cannot be guaranteed. At the same time, the process of disassembling and assembling the plated parts is also very cumbersome. Summary of the invention

[0005] An object of the present invention is to solve at least the above problems and / or disadvantages and to provide at least the advantages which will be described hereinafter.

[0006] In order to achieve these purposes and other advantages of the present invention, a gold-plating tool for batch electroplating thick gold layers on micro parts is provided, comprising: a plating rack, a gold-plating mold for placing micro-plated parts, a circuit board arranged on a support plate of the plating rack and matching the gold-plating mold, a plurality of through holes I for installing the gold-plating mold are provided on the support plate and the circuit board, corresponding conductive rings are provided at the through holes I on the circuit board, the conductive ring located at the center of the circuit board is connected to the conductive column on the plating rack, and other conductive rings except the conductive ring at the center of the circuit board are connected to the conductive ring at the center of the circuit board through wires of the same length and diameter built into the circuit board.

[0007] Preferably, the gold-plated mold comprises:

[0008] A lower fixture for loading a micro-plated part, wherein a through hole II is provided at the bottom of the lower fixture for the front end of the micro-plated part to extend out;

[0009] An upper fixture cooperates with the lower fixture to seal the micro-plated part, wherein an elastic conductive probe is disposed inside the upper fixture and abuts against the rear end mandrel of the micro-plated part;

[0010] Among them, the lower clamp is made of insulating material, the upper clamp is made of conductive material, and the outer surface of the upper clamp has a step-shaped stopping portion, the diameter of the stopping portion is larger than the diameter of the through hole I, and the lower surface of the stopping portion abuts against the conductive ring.

[0011] Preferably, it further comprises: a magnetic ring I and a magnetic ring II respectively arranged at the connection between the upper clamp and the lower clamp;

[0012] Wherein, the magnetic poles of the magnetic ring I and the magnetic ring II are opposite.

[0013] Preferably, it further comprises: a magnetic ring III arranged inside the electroplating rack at a position corresponding to the through hole I;

[0014] Wherein, the magnetic ring III is located above the magnetic ring I, and the magnetic poles of the magnetic ring III and the magnetic ring I are the same.

[0015] Preferably, a sealing ring is provided between the front end of the micro-plated component and the through hole II.

[0016] A method for electroplating micro parts, using a gold plating tool for batch electroplating a thick gold layer on micro parts according to any one of claims 1 to 5, the electroplating method comprising:

[0017] The micro-plated component mandrel is placed in the lower fixture, and the lower end of the micro-plated component to be electroplated extends out of the through hole II;

[0018] The upper fixture and the lower fixture are assembled by magnetic attraction of magnetic ring I and magnetic ring II, so that the elastic conductive probe contacts the core shaft of the micro-plated part to form an assembled sealing fixture;

[0019] Place a plurality of identical sealing fixtures on the corresponding through holes Ⅰ of the circuit board of the electroplating rack, and use the magnetic ring Ⅲ on the circuit board and the magnetic ring Ⅰ in the sealing fixture to press the sealing fixture onto the conductive ring of the circuit board;

[0020] At the same time, each conductive ring contacts the corresponding sealing fixture, and each conductive ring is connected to the central conductive ring of the circuit board through the circuit board wire with equal resistance, and then connected to the conductive column of the electroplating rack to achieve equal potential of each sealing fixture;

[0021] During the electroplating operation, the conductive column of the electroplating rack is connected to the electroplating power supply, half of the lower fixture of the sealing fixture is immersed in the electroplating solution, and finally the electroplating rack moves in a circle driven by the external bracket;

[0022] When the coating thickness reaches the specified thickness, stop electroplating;

[0023] Among them, the plating solution system is a cyanide-free sulfite system, and the plating parameters of the electroplating process are: the pH of the plating solution is between 8 and 10, the temperature of the plating solution is between 45 and 60°C, the cathode current density of the micro-plated parts is between 0.1-1A / dm2, and the anode of the plating solution is pure gold material or platinum-titanium material.

[0024] The present invention includes at least the following beneficial effects: when a relatively thick gold layer is electroplated on tiny parts in batches, the current flowing through each plated part during the electroplating process tends to be consistent without negatively affecting the surface quality, thereby ensuring the consistency of the gold layer thickness of the parts, and the electroplating tooling structure is simple and compact and easy to use.

[0025] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0027] Figure 2 It is a schematic diagram of the cooperation between the upper clamp and the lower clamp of the present invention;

[0028] Figure 3 It is a cross-sectional view of the upper fixture, the lower fixture and the micro-plated part;

[0029] Figure 4 It is a schematic diagram of the assembly structure of the upper fixture, the lower fixture and the electroplating rack;

[0030] Figure 5 This is a schematic diagram of the matching relationship between the circuit board and the gold-plating mold.

[0031] Markings in the figure: 1. upper fixture, 2. lower fixture, 3. conductive column, 4. support plate, 5. circuit board, 6. conductive ring, 7. micro-plated part, 8. elastic conductive probe, 9. magnetic ring I, 10. magnetic ring II, 11. through hole II, 12. sealing ring, 13. circuit board wire, 14. through hole I, 15. center conductive ring, 16. magnetic ring III. DETAILED DESCRIPTION

[0032] The present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0033] It should be understood that the terms such as “having”, “including” and “comprising” used herein do not exclude the existence or addition of one or more other elements or combinations thereof.

[0034] It should be noted that in the description of the present invention, the orientation or positional relationship indicated by the term is based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0035] In the description of the present invention, unless otherwise clearly stipulated and limited, the terms "installed", "provided with", "mounted / connected", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection. It can be a mechanical connection or an electrical connection. It can be a direct connection or an indirect connection through an intermediate medium. It can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] In addition, in the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0037] Figure 1The present invention shows a gold-plating tool for batch electroplating of thick gold layers on micro parts, comprising: a plating rack, a gold-plating mold for placing micro-plated parts 7, a circuit board 5 arranged on a support plate 4 of the plating rack and matching the gold-plating mold, a plurality of through holes Ⅰ14 for installing the gold-plating mold are provided on the support plate 4 and the circuit board 5, corresponding conductive rings 6 are provided at the through holes Ⅰ14 on the circuit board 5, the conductive ring located at the center of the circuit board 5 is connected to the conductive column 3 on the plating rack, and other conductive rings 6 except the conductive ring at the center of the circuit board 5 are connected to the conductive ring at the center of the circuit board 5 through wires of the same length and diameter built into the circuit board 5.

[0038] Working principle:

[0039] During the working process, the micro-plated parts 7 are first assembled into the gold-plating mold, and then multiple gold-plated molds are installed in the corresponding through holes on the support plate 4 of the electroplating rack. At the same time, the conductive part of the gold-plated mold is placed on the conductive ring 6 of the circuit board 5. The circuit board 5 is fixed to the support plate 4 of the electroplating rack by screws. Each conductive ring 6 is connected to the conductive column 3 of the electroplating rack in the center of the electroplating rack through the line on the circuit board 5, so as to realize the connection between all the plated parts and the conductive column 3 of the electroplating rack. The conductive ring 6 of the circuit board 5 is connected to the central conductive ring 15 of the circuit board 5 through the circuit board 5 wire, and the central conductive ring 15 of the circuit board 5 is connected to the conductive column 3 of the electroplating rack. There are 22 through holes Ⅰ14 and 22 circuit board wires 13 on the circuit board 5, and each wire has the same cross section and length, so that each wire has equal resistance. Each assembled sealing fixture is placed on the corresponding plated hole, so that all micro-plated parts 7 are connected to the central conductive ring 15 with equal resistance; at the same time, multiple conductive rings 6 are evenly spaced in the x-axis direction and do not block each other, so as to ensure that the electric field lines of each micro-plated part 7 are not interfered by the adjacent plated parts. Each micro-plated part 7 is connected to the conductive column 3 of the electroplating rack with equal resistance, thereby ensuring that the current flowing through each plated part during the electroplating process tends to be consistent and the thickness of the coating tends to be consistent.

[0040] In the above technical solution, the gold-plated mold includes:

[0041] A lower fixture 2 for loading the micro-plated component 7, wherein a through hole II11 is provided at the bottom of the lower fixture 2 for the front end of the micro-plated component 7 to extend out;

[0042] An upper fixture 1 cooperates with the lower fixture 2 to seal the micro-plated component 7, wherein an elastic conductive probe 8 is disposed inside the upper fixture 1 and abuts against the rear end mandrel of the micro-plated component 7;

[0043] Among them, the lower fixture 2 is made of insulating material, the upper fixture 1 is made of conductive material, and the outer surface of the upper fixture 1 has a stepped stopper, the diameter of the stopper is larger than the diameter of the through hole Ⅰ14, and the lower surface of the stopper abuts against the conductive ring 6. With this technical solution, the upper fixture 1 and the lower fixture 2 are tightly matched, and the elastic conductive probe 8 abuts against the mandrel. At the same time, the lower fixture 2 is made of insulating material and enters the plating solution to play an insulating protection role. The sealed upper fixture 1 is made of conductive material and cooperates with the elastic conductive probe 8, so that the micro-plated part 7 is charged and the surface to be plated can be plated.

[0044] The above technical solution also includes: magnetic rings I9 and II10 respectively arranged at the connection between the upper clamp 1 and the lower clamp 2; wherein the magnetic poles of the magnetic rings I9 and II10 are opposite. With this technical solution, the upper clamp 1 magnetic ring I9 inside the upper clamp 1 and the lower clamp 2 magnetic ring II10 sealing the lower clamp 2 are assembled together by magnetic attraction. The magnetic attraction method can ensure the stability of the connection and the convenience of loading and unloading, which is convenient for workers to load and unload the micro-plated parts 7 during the electroplating process, thereby improving the efficiency of electroplating.

[0045] In the above technical solution, it also includes: a magnetic ring III 16 arranged inside the electroplating rack at a position corresponding to the through hole I 14;

[0046] The magnetic ring III16 is located above the magnetic ring I9, and the magnetic poles of the magnetic ring III16 and the magnetic ring I9 are the same. With this technical solution, the gold-plated mold is placed on the electroplating rack, and the magnetic ring III16 built into the electroplating rack forms a magnetic spring with the same polarity repelling each other with the magnetic ring I9 of the gold-plated mold, pressing the gold-plated mold downward on the circuit board 5, ensuring that the upper fixture 1 can be tightly connected with the conductive ring 6 during the electroplating process of the gold-plated mold. This reduces electroplating failures or quality problems caused by poor contact, and reduces the failure rate and rework rate in the production process.

[0047] In the above technical solution, a sealing ring 12 is provided between the front end of the micro-plated part 7 and the through hole II 11. With this technical solution, the front end of the gold plating mold is sealed, which effectively prevents the plating solution from penetrating into the area that should not be plated during the electroplating process, thereby ensuring the accuracy and quality of the electroplating.

[0048] In the above technical solution, the method comprises:

[0049] The mandrel of the micro-plated component 7 is placed in the lower fixture 2, and the lower end of the micro-plated component 7 to be electroplated extends out from the through hole II11;

[0050] The upper fixture 1 and the lower fixture 2 are assembled by the magnetic attraction of the magnetic ring I 9 and the magnetic ring II 10, so that the elastic conductive probe 8 is in contact with the core shaft of the micro-plated part 7, forming an assembled sealing fixture;

[0051] Place a plurality of identical sealing fixtures on the corresponding through holes Ⅰ14 of the circuit board 5 of the electroplating rack, and use the magnetic rings Ⅲ16 and Ⅰ9 to press the upper fixture 1 and the lower fixture 2 onto the conductive ring 6;

[0052] At the same time, each conductive ring 6 contacts the corresponding sealing fixture, and each conductive ring 6 is connected to the central conductive ring 15 of the circuit board 5 through the circuit board wire 13 of equal resistance, and then connected to the conductive column 3 of the electroplating rack, so as to achieve equal potential of each sealing fixture;

[0053] During the electroplating operation, the electroplating rack conductive column 3 is connected to the electroplating power supply, and after power is turned on, it is placed on the cathode movable bracket with power, and the lower fixture 2 is half immersed in the electroplating solution to ensure that the part to be electroplated is completely immersed in the plating solution;

[0054] Finally, the cathode movement of the micro-plated part 7 is started, and the cathode moving bracket (not shown in the figure) of the micro-plated part 7 drives the electroplating rack and the electroplating fixture to make high-speed circular motion together, and a long-term electroplating gold operation is performed. Through process monitoring, the thickness of the plating layer is deposited to a specified thickness, and the electroplating is stopped;

[0055] After the electroplating is completed, the power is turned off first and then the cathode movement is stopped, the electroplating rack is removed, the electroplating fixtures are taken out from the electroplating rack in sequence, the upper and lower fixtures 2 are separated and the electroplating mandrel is taken out, and the electroplating operation is completed;

[0056] The electroplating parameters of the electroplating process are: temperature of 55°C, cathode current density of 0.7A / dm2, platinum-titanium anode. Hullcell test, electroplating time of 22s. During the electroplating process, the plating solution has good stability and is insensitive to impurities. At the same time, a thermal shock test is carried out on the micro parts after electroplating. The bonding force between the gold layer and the micro parts is good, and the plating layer is uniform.

[0057] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes, and they can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A gold plating tool for batch electroplating thick gold layers on micro parts, comprising: A plating rack for placing gold-plating molds for micro-plated parts, characterized in that a circuit board that matches the gold-plating mold is arranged on a support plate of the plating rack, a plurality of through holes I for installing the gold-plating mold are provided on the support plate and the circuit board, and corresponding conductive rings are provided at the through holes I on the circuit board, wherein the conductive ring located at the center of the circuit board is connected to the conductive column on the plating rack, and other conductive rings except the conductive ring at the center of the circuit board are connected to the conductive ring at the center of the circuit board through wires of the same length and diameter built into the circuit board.

2. The gold plating tool for batch electroplating thick gold layers of micro parts according to claim 1, characterized in that: The gold-plated mold comprises: A lower fixture for loading a micro-plated part, wherein a through hole II is provided at the bottom of the lower fixture for the front end of the micro-plated part to extend out; An upper fixture cooperates with the lower fixture to seal the micro-plated part, wherein an elastic conductive probe is disposed inside the upper fixture and abuts against the rear end mandrel of the micro-plated part; Among them, the lower clamp is made of insulating material, the upper clamp is made of conductive material, and the outer surface of the upper clamp has a step-shaped stopping portion, the diameter of the stopping portion is larger than the diameter of the through hole I, and the lower surface of the stopping portion abuts against the conductive ring.

3. The gold plating tool for batch electroplating thick gold layers of micro parts according to claim 2, characterized in that: Also includes: Magnetic ring I and magnetic ring II are respectively arranged at the connection between the upper clamp and the lower clamp; Wherein, the magnetic poles of the magnetic ring I and the magnetic ring II are opposite.

4. The gold plating tool for batch electroplating thick gold layers of micro parts according to claim 3, characterized in that: Also includes: A magnetic ring III is arranged inside the electroplating rack at a position corresponding to the through hole I; Wherein, the magnetic ring III is located above the magnetic ring I, and the magnetic poles of the magnetic ring III and the magnetic ring I are the same.

5. The gold plating tool for batch electroplating thick gold layers of micro parts according to claim 2, characterized in that: A sealing ring is arranged between the front end of the micro-plated component and the through hole II.

6. A method for electroplating micro parts, using the gold plating tool for batch electroplating thick gold layers of micro parts according to any one of claims 1 to 5, characterized in that: The electroplating method comprises: The micro-plated component mandrel is placed in the lower fixture, and the lower end of the micro-plated component to be electroplated extends out of the through hole II; The upper fixture and the lower fixture are assembled by magnetic attraction of magnetic ring I and magnetic ring II, so that the elastic conductive probe contacts the core shaft of the micro-plated part to form an assembled sealing fixture; Place a plurality of identical sealing fixtures on the corresponding through holes Ⅰ of the circuit board of the electroplating rack, and use the magnetic ring Ⅲ on the circuit board and the magnetic ring Ⅰ in the sealing fixture to press the sealing fixture onto the conductive ring of the circuit board; At the same time, each conductive ring contacts the corresponding sealing fixture, and each conductive ring is connected to the central conductive ring of the circuit board through the circuit board wire with equal resistance, and then connected to the conductive column of the electroplating rack to achieve equal potential of each sealing fixture; During the electroplating operation, the conductive column of the electroplating rack is connected to the electroplating power supply, half of the lower fixture of the sealing fixture is immersed in the electroplating solution, and finally the electroplating rack moves in a circle driven by the external bracket; When the coating thickness reaches the specified thickness, stop electroplating; Among them, the plating solution system is a cyanide-free sulfite system, and the plating parameters of the electroplating process are: the pH of the plating solution is between 8 and 10, the temperature of the plating solution is between 45 and 60°C, the cathode current density of the micro-plated parts is between 0.1-1A / dm2, and the anode of the plating solution is pure gold material or platinum-titanium material.

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