A tooling for uniformly electroplating silver on the porous and end faces of a rotor using a silver cyanide solution

Abstract

The present invention belongs to the field of electroplating of rotor parts, and specifically relates to a tooling for uniformly electroplating silver on the porous and end faces of a rotor using a silver cyanide solution. The currently used electroplating silver clamping device has problems such as poor flow of the silver cyanide solution and uneven discharge gaps. The main body of the tooling of the present invention is a glass cover with a cup-shaped structure and a certain thickness at the bottom. The glass cover has an upper threaded hole and a lower threaded hole at the center of the bottom, a wire hole at an eccentric position at the bottom, an annular groove on the inner surface of the bottom, and several inclined flow channels leading to the inner cavity of the glass cover around the circumferential direction of the lower threaded hole. The outlets of the inclined flow channels are within the range of the annular groove, and the rotor can be accommodated in the glass cover; the tooling also includes a flow dividing cover, which is a cover structure and covers the outlets of the inclined flow channels. The bottom of the cover has a central hole and several axial injection holes, and several circumferential injection holes are provided on the side of the cover. The structural design is simple, and the silver plating operation is convenient; the main body material has high strength, stable structure, and long service life.

Description

Technical Field

[0001] The present invention belongs to the field of electroplating of rotor parts, and particularly relates to a tooling for uniformly electroplating silver on the porous and end faces of a rotor using a silver cyanide solution. Background Art

[0002] In an aeroengine fuel regulating system, a plunger pump is an important fuel supply device. And the rotor is an important part of the plunger pump. The structure diagram of the rotor is shown in Figure 1 and Figure 2 . By the rotation of the rotor, the plunger is driven to reciprocate axially in the rotor hole to squeeze the fuel, so that the fuel is continuously pressurized to achieve the purpose of fuel supply.

[0003] During the operation of the rotor, there is reciprocating motion between the rotor hole and the plunger, and rotational motion between the rotor end face and the oil distribution plate, resulting in a large amount of friction and wear. By electroplating silver on the rotor hole and end face, the wear rate is reduced and the service life of the plunger pump is increased.

[0004] The currently used electroplating silver clamping device has problems such as poor flow of the silver cyanide solution and uneven discharge gaps, resulting in uneven thickness, insufficient bonding force, and insufficient density of the silver plating layer. Summary of the Invention

[0005] The purpose of the present invention is: to solve the above problems, the present invention designs a tooling for uniformly electroplating silver on the porous and end faces of a rotor using a silver cyanide solution, so that a silver layer with uniform thickness, strong bonding force, and consistent density is formed on the silver-plated surface of the rotor.

[0006] The technical solution of the present invention is: a tooling for uniformly electroplating silver on the porous and end faces of a rotor using a silver cyanide solution. The main body of the tooling is a glass cover with a cup-shaped structure and a certain thickness at the bottom. The glass cover has an upper threaded hole and a lower threaded hole at the center of the bottom, a wire hole at an eccentric position at the bottom, an annular groove on the inner surface of the bottom, and a plurality of inclined flow channels leading to the inner cavity of the glass cover around the circumferential direction of the lower threaded hole. The outlets of the inclined flow channels are within the range of the annular groove, and the rotor can be accommodated in the glass cover;

[0007] The tooling further includes a flow dividing cover, which is a cover structure and covers the outlets of the inclined flow channels. The cover has a central hole and a plurality of axial injection holes at the bottom, and a plurality of circumferential injection holes on the side surface. A connecting nozzle for filling the silver cyanide solution is installed in the lower threaded hole; the rotor is fixed in the glass cover through a screw. One end of the screw passes through the central hole of the rotor and the flow dividing cover and then connects to the upper threaded hole, and the other end connects to an auxiliary cathode;

[0008] The pole ring is placed in the annular groove, and the iron wire is hermetically installed in the wire hole. The inner end of the iron wire is electrically connected to the pole ring, and the outer end passes through the glass cover to connect to the auxiliary anode; in the annularly arranged holes of the rotor, the pole columns are inserted with clearance fit and are connected to the auxiliary anode.

[0009] A pressing cylinder is press-fitted on the upper part of the rotor. The upper end of the screw rod passes through the pressing cylinder, the gasket and the pole piece and is connected to the third nut, and the pole piece is connected to the auxiliary cathode.

[0010] The pressing cylinder has an annular support plate with circumferentially arranged mounting holes, and the mounting holes are coaxial with the annularly arranged holes of the rotor. The pole columns are inserted into the mounting holes through externally tapered positioning pins.

[0011] On the support plate, the wiring piece and one end of the copper braid are fixed by the first screw and the third washer. The other end of the copper braid has a copper sleeve, and the copper sleeve is fixed to the upper end of the pole column by a diamond nut. The wiring piece is connected to the auxiliary anode.

[0012] A plug is installed at the lower end of the central hole of the rotor. The screw rod includes a third screw rod at the upper part and a second screw rod at the lower part. The third screw rod is inserted into the upper end of the plug, and the lower end of the plug is threadedly connected to the second screw rod.

[0013] The plug has a brass material matrix on the inner layer, a threaded hole on the inner hole, a layer of rubber on the outer cylindrical surface of the matrix, and a serrated annular groove on the outer cylindrical surface of the rubber.

[0014] A second washer is provided between the third screw rod and the plug.

[0015] The outer end of the iron wire is connected to one end of the first screw rod through the first nut and the first washer. The other end of the first screw rod is connected to the auxiliary anode, and a second screw plug is installed in the wire hole.

[0016] A second nut is also installed on the screw rod and is pressed against the upper part of the shunt cover.

[0017] The rotor is also pressed on the side wall of the glass cover by the third screw.

[0018] The advantages of the present invention are: the structural design is simple, and the silver plating operation is convenient; the main body material has high strength, stable structure and long service life; the silver cyanide solution flows concentratedly through the silver plating surface, saving the solution consumption; the solution flow rate is uniform and the discharge gap is consistent, ensuring the uniformity of the silver layer thickness. [[ID=A]] [[ID=B]]BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is the axial sectional view of the rotor structure;

[0020] Figure 2 is the left view of the rotor structure;

[0021] Figure 3It is a schematic diagram of the overall structure of the electroplated silver tooling of the present invention;

[0022] Figure 4 It is a sectional view of the glass cover structure;

[0023] Figure 5 It is a left view of the glass cover;

[0024] Figure 6 It is an axonometric drawing of the glass cover;

[0025] Figure 7 It is a sectional view of the structure of the plug;

[0026] Figure 8 It is an oblique view of one side of the shunt cover;

[0027] Figure 9 It is an oblique view of the other side of the shunt cover.

[0028] In the figure, 1 - nozzle, 2 - first plug, 3 - second plug, 4 - iron wire, 5 - first nut, 6 - first washer, 7 - first screw rod, 8 - pole ring, 9 - second nut, 10 - second screw rod, 11 - plug, 12 - third screw rod, 13 - second washer, 14 - positioning pin, 15 - first screw, 16 - third washer, 17 - copper braid, 18 - connection piece, 19 - diamond nut, 20 - pole column, 21 - pole piece, 22 - gasket, 23 - third nut, 24 - copper sleeve, 25 - second screw, 26 - support plate, 27 - support, 28 - third screw, 29 - glass cover, 30 - shunt cover, 31 - rotor Detailed implementation mode

[0029] The following further details the present invention. Refer to Figure 3-9 , a clamping device for uniformly flowing a silver cyanide solution through the pores of the rotor and simultaneously electroplating silver on the end face, used for simultaneously electroplating silver on 7 A holes and the B surface of the rotor 31, including a nozzle 1, a first plug 2, a second plug 3, an iron wire 4, a first nut 5, a first washer 6, a first screw rod 7, a pole ring 8, a second nut 9, a second screw rod 10, a plug 11, a third screw rod 12, a second washer 13, a positioning pin 14, a first screw 15, a washer 16, a copper braid 17, a connection piece 18, a diamond nut 19, a pole column 20, a pole piece 21, a gasket 22, a third nut 23, a copper sleeve 24, a second screw 25, a support plate 26, a support 27, a third screw 28, a glass cover 29, a shunt cover 30, and a rotor 31.

[0030] The glass cover 29 is of a cylindrical structure, with cylindrical holes machined at both ends. One end has a large hole with a thin wall for placing the rotor 31, and the other end has a small hole for installing the nozzle 1. The large and small holes on the upper and lower parts of the glass cover 29 are connected by 7 inclined holes for the flow of silver cyanide solution. A threaded hole is machined at the bottom of the large hole at the upper end of the glass cover 29 for installing the second screw 10, and the shunt cover 30 is tightened by the second nut 9. There are 3 threaded holes on the side wall of the large hole at the upper end of the glass cover 29 for installing the third screw 28 to tighten and fix the rotor 31. The pole ring 8 is inlaid at the bottom of the large hole at the upper end of the glass cover 29. The pole ring 8 is connected to the iron wire 4 by welding. The iron wire 4 extends to both sides of the glass cover 29 through the "T"-shaped holes on both sides at the lower end of the glass cover 29 and is connected to the first screw 7 by the first nut 5 and the first washer 6 for connecting the auxiliary anode. A mixture of polyamide resin and epoxy resin is filled in the 2 "T"-shaped holes at the lower end of the glass cover 29, and the 4 orifices are tightened and extruded by the first plug 2 and the second plug 3 respectively to ensure solidification after compaction and prevent the steel wire from shaking, so that the iron wire 4 and the glass cover 29 are integrated. The material selected for the glass cover 29 is polycarbonate, which is transparent for observation. Compared with materials such as plexiglass, it has high strength, stable structure, long service life, is insulated, insoluble in silver cyanide solution, and has good stability in silver cyanide solution;

[0031] The shunt cover 30 has 6 inclined holes running through the upper and lower parts and 6 radial rotating grooves on the bottom surface for the uniform flow of silver cyanide solution.

[0032] The plug 11 consists of two parts. A layer of rubber is coated on the outer cylindrical surface of the base body. The base body is made of brass material, and the inner hole is a threaded hole for installing on the second screw 10. The outer cylindrical surface has a serrated ring groove to increase the bonding force of the rubber. The outer circle of the rubber is conical for supporting the rotor 31 and blocking the middle hole of the rotor 31. The third screw 12 passes through the second washer 13, the rotor 31, the support 27, the gasket 22, and the pole piece 21 in sequence and is fastened by the third nut 23. The pole piece 21 is connected to the auxiliary cathode for conducting the rotor 31 and the auxiliary cathode. The support plate 26 is installed on the support 27, and the clearance between the middle hole and the outer circle of the support 27 is within 0.02 mm. The distance from the installation surface of the support 27 for installing the support plate 26 to the bottom surface is 30 ± 0.05 mm.

[0033] The support plate 26 is evenly distributed with 7 inclined conical holes. When installing, it is necessary to ensure that the coaxiality of the axes of each hole and the holes of the rotor 31 is within 0.04 mm. The intersection of the axis of the inclined conical hole of the support plate 26 and the bottom surface is within the ring with a diameter of φ77.67 ± 0.0, and the angle between the axis of each hole and the axis of the middle hole of the support plate 26 is 15° ± 5'. The diameter of the small end orifice is φ17 + 0.043 / 0 mm.

[0034] The upper end of the positioning pin 14 is conical and mates with the conical hole of the support plate 26. The lower end is cylindrical, dimensionally grouped, and mates with the hole of the rotor 31. The cylindrical surface of the positioning pin 14 is divided into two groups, namely φ14.03 and φ14.05, with a tolerance of 0 / 0.01 mm. The positioning pin 14 passes through the support 27 and inserts into the hole of the rotor 31 to ensure angular consistency when installing the support plate 26 and the hole of the rotor 31. The positioning pin 14 with the smallest clearance from the hole of the rotor 31 should be selected, and the angular orientation of one hole can be determined.

[0035] The support plate 26 has 3 M3 screw holes radially for locking the support plate 26 and the support 27. Seven pole columns 20 are respectively inserted into the seven inclined conical holes of the support plate 26. The pole columns 20 are connected to the support plate 26 with copper braids 17, and both ends of the copper braids 17 are fastened with the first screw 15, the third washer 16, the diamond nut 19, and the copper sleeve 24 respectively.

[0036] The diameter of the small end face of the conical surface of the pole column 20 is φ11.70 / -0.1 mm; the diameter of the cylindrical surface of the pole column 20 is φ

[0037] 4.80 / -0.1 mm, and the coaxiality with the conical surface is R0.02 mm. The cylindrical end face of the pole column 20 is designed as a 40° full-angle cone with a tip rounded at R0.5 mm for solution diversion. One end of the connecting piece 18 is fixed on the support plate 26, and the other end is connected to the auxiliary anode for connecting the pole column 20 and the auxiliary anode.

[0038] The outer circle of the nozzle 1 is designed with parallel planes for wrench installation; the outer circle of the lower end is designed with multiple tapered ring grooves for installing quick-release pipe joints. The nozzle 1, the first plug 2, the second plug 3, and the flow dividing cover 30 are all made of plexiglass, which is insulated, insoluble in silver cyanide solution, and low-cost. The second nut 9, the second screw 10, and the third screw 28 are all made of polytetrafluoroethylene, which is insulated, insoluble in silver cyanide solution, soft in material, and will not damage parts.

[0039] The support 27 is made of cloth-impregnated bakelite, which is insulated, insoluble in silver cyanide solution, has a certain strength, and is low-cost.

[0040] The iron wire 4, nut 5, first washer 6, first screw 7, pole ring 8, third screw 12, first screw 15, third washer 16, diamond nut 19, pole column 20, third nut 23, and second screw 25 are all made of 1Cr18Ni9Ti, which has good electrical conductivity, is stable in silver cyanide solution, does not contaminate silver cyanide solution, and has a long service life.

[0041] The second washer 13, copper braid 17, wiring piece 18, pole piece 21, gasket 22, copper sleeve 24, and support plate 26 are all made of pure copper, which has strong electrical conductivity, can accelerate the movement of silver ions in silver cyanide solution, is stable in silver cyanide solution, and does not contaminate silver cyanide solution.

[0042] The locating pin 14 is made of QSn4-3 to improve its wear resistance.

[0043] The clearance between the bottom ring groove of the hole of the glass cover 29 and the pole piece 8 is 0.03 mm to 0.1 mm.

[0044] The difference between the distance from the pole ring 8 to the bottom surface of the rotor 31 and the distance from the pole column 20 to the hole wall of the rotor 31 is not more than 0.5 mm.

[0045] The working principle is as follows: Connect the rotor to the auxiliary cathode, and connect the pole piece and the pole column in the tooling to the auxiliary anode. Inject silver cyanide solution into the glass cover. After power-on, utilize the electrolysis principle to make silver ions adhere to the surface of the rotor to form a metal film. To ensure the uniformity of the silver layer thickness, it is necessary to ensure that the distances between the pole piece and the pole column and the silver-plated surface of the rotor are the same, and the flow rate of the silver cyanide solution flowing through the silver-plated surface of the rotor should be uniform.

[0046] Before use, first pass the third screw 12 through the second washer 13, the rotor 31, the support 27, the gasket 22, and the pole piece 21 in sequence, and fasten it with the third nut 23; then place the rotor 31 into the large hole at the upper end of the glass cover 29, make the middle hole of the rotor 31 sit on the plug 11, and adjust the distance between the bottom surface of the rotor 31 and the pole ring 8 by adjusting the depth of the second screw 10 screwed into the bottom thread of the hole of the glass cover 29; fasten the rotor 31 with 3 third screws 28; install the support plate 26 on the support 27, select a locating pin 14 with a suitable diameter, pass through the tapered hole of the support plate 26 and the silver-plated hole of the rotor 31 in sequence to complete the angular positioning of the support plate 26, and fasten the support plate 26 and the support 27 with 3 second screws 25; take out the locating pin 14, install 7 pole columns 20, and conduct electricity between the support plate 26 and the pole columns 20 with a copper braid 17; connect the nozzle 1 to the quick-release pipe joint at the outlet of the silver cyanide solution pump;

[0047] During operation, vertically place the installed silver plating device on the bracket of the solution tank. Connect the first screw 7 and the connecting piece 18 to the power anode, and connect the pole piece 21 to the power cathode; turn on the silver cyanide solution pump to make the solution flow into the silver plating device from the nozzle 1. After the flow rate is stable, turn on the power supply to start silver plating timing; determine the silver plating time according to the silver plating thickness. After silver plating is completed, turn off the power supply, disassemble the power connection wire and the quick-release pipe joint at the outlet of the silver cyanide solution pump, take out the silver plating device from the solution tank and drain the solution; remove the copper braid 17, take off the pole columns 20, loosen the second screws 25 to remove the support plate 26; loosen the third screws 28, take out the rotor 31 from the glass cover 29, and then disassemble other parts.

Claims

1. A tooling for uniformly electroplating silver on the porous and end faces of a rotor using a silver cyanide solution, characterized in that: The main body of this tooling is a glass cover (29) with a cup-shaped structure and a certain thickness at the bottom. The glass cover (29) has an upper threaded hole and a lower threaded hole at the center of the bottom, a wire hole at an eccentric position at the bottom, an annular groove on the inner surface of the bottom, and the lower threaded hole has a number of inclined flow channels leading to the inner cavity of the glass cover (29) around the circumference. The outlet of the inclined flow channel is within the range of the annular groove, and the rotor (31) can be accommodated in the glass cover (29). This tooling further includes a shunt cover (30), which is a cover structure and covers the outlet of the inclined flow channel. The cover has a central hole and a number of axial injection holes at the bottom of the cover, and a number of circumferential injection holes on the side of the cover. A nozzle (1) for filling silver cyanide solution is installed in the lower threaded hole; the rotor (31) is fixed in the glass cover (29) by a screw. One end of the screw passes through the central hole of the rotor and the shunt cover (30) and then connects to the upper threaded hole, and the other end connects to the auxiliary cathode; a plug (11) is installed at the lower end of the central hole of the rotor. The screw includes a third screw (12) at the upper part and a second screw (10) at the lower part. The third screw (12) is inserted into the upper end of the plug (11), and the lower end of the plug (11) is threadedly connected to the second screw (10). A second nut (9) is also installed on the screw, which presses against the upper part of the shunt cover (30). A pole ring (8) is placed in the annular groove, a wire (4) is hermetically installed in the wire hole, the inner end of the wire (4) is electrically connected to the pole ring (8), and the outer end passes through the glass cover (29) to connect to the auxiliary anode; in the annularly arranged holes of the rotor (31), pole columns (20) are inserted with clearance fit, which are connected to the auxiliary anode.

2. The electroplated silver tooling according to claim 1, characterized in that: A pressing cylinder is press-fitted on the upper part of the rotor (31). The upper end of the screw passes through the pressing cylinder, a gasket (22) and a pole piece (21) and then connects to a third nut (23), and this pole piece (21) is connected to the auxiliary cathode.

3. The electroplated silver tooling according to claim 2, characterized in that: The pressing cylinder has an annular support plate (26), and the support plate (26) has circumferentially arranged mounting holes, and the mounting holes are coaxial with the annularly arranged holes of the rotor. The pole columns (20) are inserted into the mounting holes through externally tapered positioning pins (14).

4. The electroplated silver tooling according to claim 3, characterized in that: A wiring piece (18) and one end of a copper braid (17) are fixed on the support plate (26) by a first screw (15) and a third washer (16). The other end of the copper braid (17) has a copper sleeve (24), and the copper sleeve (24) is fixed to the upper end of the pole column (20) by a diamond-shaped nut (19). The wiring piece (18) is connected to the auxiliary anode.

5. The electroplated silver tooling according to claim 1, characterized in that: The plug (11) has a brass material matrix on the inner layer, the inner hole is a threaded hole, the outer cylindrical surface of the matrix has a layer of rubber, and the outer cylindrical surface of the rubber has a serrated annular groove.

6. The electroplated silver tooling according to claim 1, wherein: A second washer (13) is provided between the third screw (12) and the plug (11).

7. The electroplated silver tooling according to claim 1, wherein:

8. The electroplated silver tooling according to claim 1, characterized in that: The outer end of the wire (4) is connected to one end of a first screw (7) through a first nut (5) and a first washer (6). The other end of the first screw (7) is connected to the auxiliary anode, and a second plug (3) is installed in the wire hole. The rotor (31) is also pressed on the side wall of the glass cover (29) by a third screw (28).

Images