US2431949A

US2431949A - Apparatus for electroplating the inside of bearing shells and the like

Info

Publication number: US2431949A
Application number: US511517A
Authority: US
Inventors: William M Martz
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1943-11-24
Filing date: 1943-11-24
Publication date: 1947-12-02
Anticipated expiration: 1964-12-02

Description

Dec. 2, 1947.

J W. M. MARTZ APPARATUS FOR ELECTROPLATING THE INSIDE OF BEARING SHELLS AND THE LIKE Filed Nov. 24, 1945 3 Sheets-Sheet 1 &

2 i U Q Q Bunentor @Zflz%izazz? Dec.2, 1947. WMMARTZ v 2,431,949

APPARATUS FOR ELECTRQPLATING THE INSIDE OF BEARING SHELLS AND THE LIKE u M y (Ittornegs Dec. 2, 1947'. w. M. MARTZ 7 2,431,949

APPARATUS FOR ELECTROPLATING THE INSIDE OF BEARING SHELLS AND THE LIKE Filed NOV. 24, 1943 3 Sheets-Sheet 5 o o o B r" #T Q LEI g b Ming L) A Ll J I U s "Tb v a UNITED Patented Dec. 2, 1947 STATES PATENT APPARATUS FOR ELECTROPLATING THE IN- SIDE OF BEARING SHELLS AND THE LIKE Application. November 24, 1943, Serial No. 511,517

OFFICE 3 Claims.

This invent on relates generally to the art of electrodepositing metals and more particularly to electrodepositi-ng a layer or coating of metal on the inside of bearing shells and the like.

High quality bearings such as employed in airdisadvantages.

ties.

and /or cathode.

the bearing shells by simple means.

ternal masking devices are necessary.

shell at a time in each unit.

an improved apparatus. for plating bearing, shells 2 and the like that eliminates defects in devices heretofore employed. 7

Another object of the invention is the provision of an apparatus for plating bearings and. the

like that is characterized by its simplicity and ease craft engines may be made by electrodepositing a of control. layer or layers. of relatively soft metal or alloy A further object of the invention is the provihaving good antifrictional properties onto a supsion of an improved device of the class described port of a harder and stronger metal whi"h acts in which it is practical to filter the plating soluas the cathode during the plating operation. 10 tion so that only filtered. solution flows past the Different forms of apparatuses have been procathode. v posed heretofore for electrodepositing metal on It is a further object of. the invention to prothe inside of bearing shells and the like. Wh le vide an improved apparatus for plating the inside some of the plating apparatuses or devices have of bearing shells and the like that eliminates the. given satisfactory results and. many high quality necessity of employing masking, devices for the bearings produced thereby, all those apparatuses outside of the bearing shells. of which I am aware are subject to one or more A further object of the. invention. is to provide an. improved means for maintaining a fresh and In plating bearings and the like it is desirable undepleted supply of plating solution at the. sur to electrodeposit the relatively soft metal at a faces to be plated.

rapid rate requiring relatively high current densi- It is also an object. of the invention to provide This factor, along with others, makes it an improved device of the class described in which necessary or advantageous to provide a considerno rotary devices are. required in theelectrolyte. able amount of agitation of. the plating solution. Another object of the invention is to provide In some apparatuses heretofore employed reliance a device of the class described inwhich only a. isplaced on more or less complicated devices to small amount of floor space is required per stack. agitate or rotate the anode and/or cathode durof bearings or other articles being plated. ing the process of electrodeposition inorder to A further. obiect of the invention is the proviprovide effective agitation and to bring a supply sion of a simplified apparatus for plating bearing. of fresh plating solution to the inside surface. of shells at rapid rate and whereby a plurality of. the bearing shells. In other constructions a roe bearings can be plated. at one time at each of a. tary means such as an impeller may be employed plurality of stations. v to provide agitation of the plating solution and Another object of this inventionis the provi-- which rotary means may be employed either by sion in a device of the class described: of means itself or with means toagitate or rotate the anode for maintaining the plating solution at substan- Such movable means are not tially a constant composition. required in the preferred embodiment of my in- Other objects and advantages of the invention vention and the plating solution is agitated anda will become more apparent from the detailed. supply of fresh plating solution is" brought condescription which follows. tinuously into contact w th the inside surface of Reference is herewith made to the accompanying drawings illustrating an apparatus in accord- Another disadvantage of some apparatuses ance with one embodiment of the invention. heretofore employed is that masking of the bear- In the drawings: ing back or shell forming the cathode is neces- Figure 1 is an elevational view partly in section sary. The pro-edure of applyingthemasks and" illustrating an apparatus in accordance with the removing the same after plating is not only time invention and showing specifically the construcconsuming but the masks are acause of plating tion at one of a plurality of. stations. rejections due to platingsolut on being trapped Figure 2 is an enlarged. sectional view of a. in the various types of masks employed. In the slightly mod fied form of a portion of a device preferred embodiment of my invention no exillustrated in Figure 1. the view being taken on a Some line corresponding to 22 in Figure 1. devices. also, are able to plate a single bearing Figure 3 is an elevational. view of the device of Fi ure 1 showing a. plurality of plating. stations. One object of the invention is the provis on of 5 In the drawings, i0 indicates a suitable tank having therein a. supply l2v of. the. plating solution.

or electrolyte. A pipe It has one end extending into the electrolyte and its other end leads to a suitable pump IE. An adjustable valve I1 is provided in pipe [4 for adjustably controlling the flow of the electrolyte. The discharge side 18 of the pump. leads to filters l9 and 2B for filtering the electrolyte. After leaving the second filter the electrolyte passes through pipe 22 to pressure cylinder 24. From the pressure cylinder 24 the electrolyte passes through a pipe 26 having a valve 21 therein into a chamber 28 in a hollow support 30 formed of a suitable non-conductor of electricity, such as hard rubber. Mounted in the hollow support 30 intermediate its ends is a hard rubber plug 32 having angularly disposed jet openings B l adapted to impart a spiralling efiect to the electrolyte as it flows therethrough. Arranged above the support 36 are a plurality of bearing shells 36, in this case four in number. Soft rubber gaskets 38, 40 and 32 are positioned between the adjacent bearing shells. Surrounding the adjacent ends of the bearing shells and the rubber gaskets 38, 4D and 32 are metallic clamping rings 44, 46 and d8. The metal clamping rings are secured to the bearing shells by screws 45 shown in Figure 2. When the screws are loosened the clamping rings may be removed and the bearing shells separated from one another. The four bearing shells together with the gaskets 38, 40 and 42 and the corresponding clamping rings form a generally tubular assembly or-stack through which the electrolyte can flow, the gaskets preventing the plating solution from escaping. A soft rubber gasket forms a liquid tight seal between the lower end of the lowermost bearing shell and the hard rubber support 30. Above the uppermost end of the uppermost bearing shell is another soft rubber gasket 52 which forms a tight seal between the upper bearing shell and a hard rubber cap or closure member 54. The closure 54 has a downwardly extending wall 56 which surrounds the upper end of the uppermost bearing shell and has

curved portions

58, 69 for directing the electrolyte downwardly and into a hollow anode 62 within the several bearing shells and coaxially therewith. The plating solution then passes downwardly through the tubular anode and is discharged into the tank It). Figure 1 illustrates one type of clamp or holding means for the cap. In this figure the closure or cap 54 is held in position by screw-clamping means 64 mounted in an arm 65 rotatably carried by a stationary column 66. The screw-clamping means 64 is tightened or loosened by the hand wheel 558. When the means 64 is in loosened position the arm 65 and parts carried thereby can be swung to one side to permit easy removal of a plated set of bearing shells and easy insertion of an unplated set. Handle members and 12 are fixed to ring 46. By means of the handles the entire stack of bearings can be removed as a unit, whereupon a new stack of unplated bearing shells can be placed in position for plating.

A modified form of construction for holding a cap 54 in place is shown in Figure 2. This construction additionally includes member 69 interposed between the end of screw 6% and the cap 54. Fixed to member 69 are two headed-rod members 10', H which pass loosely through a support 12'. The purpose of member 69 is to apply pressure to the cap 54 over a wider area than may be had by the screw 6 alone.

In all cases it is not required that a clamping means be used to hold the cap in position. The

downwardly extendlng wall 56 of the cap 54 may form a sufficiently tight fit with the upper bearing shell as to be held in frictional engagement with the bearing shell during the plating operation. This lever device may be a cam action or other similar type. In some cases, if the solution flow is controlled, there is no need for the cap device 54, consequently no need for the looking device. All that is necessary in this case is to have the top of the anode tube 62 slightly below the top of the uppermost bearing and then adjust the flow so that the anode tube can accommodate the flow of electrolyte which is forced through the bearing stack and then drains by gravity through the anode tube. This means that the usual flow of electrolyte which has passed through the bearing stack at any given time (when using a cap device) must be decreased.

In the constructions shown herein the hollow anode 62 is of insoluble material. Where the metal being plated is silver, for example, the insoluble anode 62 may be of iron or platinum. Where an insoluble anode is used it is necessary to replenish the metal that is electro-deposited out of the electrolyte. In the apparatus illustrated this is accomplished by connecting the positive bus bar st to a silver anode 86 in the electrolyte in the reservoir or tank l0, connector 88 being provided for this purpose. Extending into the electrolyte in the tank and arranged near the anode 86 are porous cups 99 and 92 having sheet steel cathodes 94 and 95 respectively arranged therein. The two cathodes 94 and 95 are connected to each other by current conductor 98. A current conductor I00 connects the two cathodes 94 and 96 to the hollow anode 62 at point Hll. Current conductor I02 rheostat I54 having means N15 for varying the I resistance therein, and conductor I06 connect the stacks of bearing shells as cathode to a negative bus bar I 68. During the plating operation the current flow from positive bus bar 84 to negative bus bar I68 is through conductor 88 to anode 83, through the electrolyte in tank I l to the cathodes 94 and 96, then through conductorlflll to the hollow anode 62, through the electrolyte flowing in the space between the hollow anode and stack of bearing shells as cathode, then through conductor I02, rheostat H34 and conductor N36 to the negative side of the line. By means of the described system, a silver is plated on the inside of the several bearing shells making up the stack by means of electric current passing through the electrolyte flowing between the hollow anode and stack of bearings an equivalent weight of silver is put back into solution through the porous cell arrangement. This maintains a substantially constant electrolyte composition.

The hollow anode 62 might be made of the material to be deposited and in such case the porous cell arrangement could be dispensed with. In this case the hollow anode 62 is directly connected to the positive bus bar. In this case the hollow anode 62 must be renewed from time to time as it passes into solution upon electrolysis.

Where an insoluble anode 62 is employed the metal that is plated out could be replenished from time to time by adding a salt of the metal to be electrodeposited to the solution in the tank or reservoir. This does not maintain a substantially constant bath composition as does the porous cell arrangement illustrated in Figure 1 of the drawings.

Figure 3 illustrates the manner in which more assists than one stack of bearing shells may be plated at one time. In this instance there are six stations. At station 6 is shown in dotted outline one stack or assembly oi bearing shells, cover and support similar to that shown in Figure 1. A similar assembly may be mounted at each of stations I to inclusive. The flow of electrolyte to each station may be cut off entirely or controlled in amount by the individual valves 21 in the similar individual pipes 2-6 leading to the several stations from the pressure cylinde 24. The capacity of the pressure cylinder 2.4 is preferably made relatively large whereby the shutting off of one or more of the valves 21 will have comparatively little effect on the new characteristics through the remaining plating units.

At each station there may be a porous cell system similar to that at the station shown in Figure 1 in order to maintain the electrolyte composition or concentration substantially constant.

In the operation of the apparatus an assembled stack of unplated bearing shells including the rubber gaskets. and clamping rings will be mounted in a hollow support 30 and in spaced relation to a hollow anode. A rubber cap 54 will then be placed over the upper end of the stack of bearing shells and held thereon as by clamping or holddown means '64. A suitable conductor I02 may be then attached to the stack of bearing shells which form the cathode. The

pump I6 is operated to pump electrolyte from the tank Ill to the pressure tank 24 and during its fiow it is passed through the filtering devices l9 and 20. The valve I! may be adjusted to control the flow of electrolyte. From the pressure tank the electrolyte flows through the pipes 26 each having an adjustable valve 21 to control or shut off the electrolyte, into the hollow supports 3|], then upwardly through the jet or orifice plates 32 into the spaces between the anodes and stacks of bearing shells and finally by means of the curved surfaces on the caps 54 into the hollow anodes where the electrolyte is returned to the tank Ill. The orifice or jet plates 32 impart effective agitation to the electrolyte as it passes between the hollow anodes and stacks of bearing shells. High current densities may be employed because of the effective agitation. The electrolyte is kept out of contact with the outer sides of the several bearing shells and no masking is required, By means of the filters as described only clean filtered solution or electrolyte comes in contact with the bearing shells being plated. In the construction employing the porous cell arrangement in the electrolyte in tank l2, the concentration or composition of the electrolyte may be maintained substantially constant at all times.

When a desired thickness of metal has been deposited it is a relatively simple matter to remove a plated stack of bearing shells and to insert an unplated stack. The entire construction is characterized by its simplicity and ease of control and adjustment.

Various changes and modifications of the embodiments of my invention described herein may be made without departing from the spirit and principles of my invention.

I claim:

1. An apparatus for electrodepo-siting metal on the inside of bearing shells and the like, a first tank containing a supply of electrolyte, a pressure tank, a pump for pumping electrolyte from the first tank to the pressure tank, a plurality of pipes leading from the pressure tank, a plurality of hollow supports above the first tank, each of which is adapted to support a stack of bearing shells forming a tubular cathode and each of which receives electrolyte through one of the pipes, a tubular anode of insoluble material within each of the stacks of bearing shells, spaced therefrom and extending downwardly through a hollow support, a cap member for the upper end of each of the stacks of bearing shells and being spaced from one end of the tubular anode within the corresponding stack of bearing shells, the ar rangement of each hollow anode, stack of bearing shells, and cap thus being such that electrolyte is caused to flow upwardly in the space formed by an anode and stack of bearing shells until it reaches the top of said stack and then is directed by the cap downwardly into and through the 1101-- low anode for return to the first tank, a plurality of anodes of the metal to be electrodeposited on the bearing shells disposed in the electrolyte in the first tank, a porous cup adjacent each last mentioned anode, a cathode within each porous cup, and electrical connections from the positive side of a source of direct current to each of the last mentioned anodes, from each of the last mentioned cathodes to each of the hollow anodes, and from each of the stacks of bearing shells to the negative side of the source of direct current whereby as metal is electrodeposited onto the inside of the stacks of bearing shells a corresponding amount of metal goes into solution in the electrolyte in said first tank.

2. An apparatus as in claim 1 in which an annular plate having angularly arranged jet openings is mounted in each hollow support between an anode and the walls of said hollow support at a point below a stack of bearing shells whereby a spiralling effect is imparted to the electrolyte as it flows through said openings and upwardly in the space formed by an anode and stack of bearing shells.

' 3. An apparatus for electrodepositing metal on the inside of bearing shells and the like comprising, a first tank containing a supply of electrolyte, a pressure tank, a pump for pumping electrolyte from the first tank to the pressure tank, a plurality of generally cup-shaped supports above said first tank, each cup-shaped support having a base and upwardly extending walls of generally circular shape, the upper portions of said walls adapted to engage in liquid tight-relation and support a stack of bearing shells connected together to form a tubular cathode, each one of said bases having an opening centrally arranged therein, a plurality of tubular anodes of material insoluble in the electrolyte, each anode having an upper portion within a tubular cathode, an intermediate portion within a cup-shaped support and a lower portion extending through one of said openings, each one of said upper portions being spaced from one of said tubular cathodes to form an annular passageway for electrolyte between a tubular cathode and a said upper portion, each one of said intermediate portions being spaced from said walls and forming therewith a passage of annular shape, each one of said lower portions being in liquid-tight engagement with one of said openings, a plurality of annular plugs, each of said plugs being supported in a said annular passage between said intermediate portion and said walls at a point between said base and upper end of said walls, each of said plugs having angularly arranged jet openings to impart a spiralling efl'ect to electrolyte as it flows therethrough, a plurality of caps, each of said caps being'in liquid-tight engagement with the upper end of one of said tubular cathodes and spaced from the upper end of one of said tubular anodes, a plurality of pipes leading from the pressure tank, each of said pipes being connected to one of the cup-shaped supports below the annular plug therein, whereb electrolyte under pressure is caused to flow through the angularly arranged openings, then spirally upward through a said annular passage to the upper end of a tubular cathode and then downwardly through each tubular anode to said tank, valve means in each of said pipes, a plurality of anodes of the metal to be deposited on the bearing shells disposed in the electrolyte in said first tank, a porous cup adjacent each last mentioned anode, a, cathode within each porous cup, and electrical connections from the positive side of a source of direct current to each of the last mentioned anodes, from each of the last mentioned cathodes to each of said tubular anodes, and from'each of the stacks of bearing shells to the negative side of the source of direct current whereby as metal is electrodeposited onto the inside of the stacks of bearing shells a corresponding amount of metal goes into solution in the first tank.

WILLIAM M. MARTZ.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 742,443 Johnson Oct, 27, 1903 746,748 Schwartz Dec. 15, 1903 899,226 Lutz Sept. 22, 1908 1,982,009 McKinney Nov. 27, 1934 588,740 Becker Aug, 24, 1897 1,467,202 Slatineanu Sept, 4, 1923 2,137,806 Paige Nov. 22, 1938 631,040 Greenawalt Aug, 15, 1899 1,371,414 Edison Mar, 15, 1921 57,412 Van der Weyde Aug. 21, 1866 1,372,928 Barton Mar. 29, 1921 1,861,446 Maag June 7, 1932 908,937 Bayliss et a1 Jan. 5, 1909 1,927,162 Fledler et al Sept. 19, 1933 2,086,841 Bagley et a1 July 13, 1937 1,796,651 I-Iarty et al Mar. 10, 1931 FOREIGN PATENTS Number Country Date 312,598 Great Britain May 27, 1939 1 625,071 France Nov. 27, 1937 OTHER REFERENCES -The Principles of Electro-Deposition, Field, pubiished by Longmans, Green and C0., New York, 1911, pages and 151, paragraph entitled Electrolytic Method."