US2739117A - Electroplating fixture - Google Patents

Description

March 20, 1956 H. c. LUECHAUER ETAL 2,739,117

ELECTROPLATING FIXTURE Filed June 18, 1952 2 Sheets-Sheet 2 IN V EN TORS HOLLE C. LUECHHUER HNTo/Y F. Ee/c/(saw My k 11kb, 9%

77/572 ATTORNEYS United States ELECTROPLATING FIXTURE Holle C. Luechauer and Anton F. Erickson, Payton,

Ohio, a'ssignors to General Motors Corporation, Detroit, Witch, :1 corporationof Delaware of semicircular bearings while immersed in a bath for electroplating purposes.

It is among the objects of the present invention to provide a fixture for holding a plurality of semicircular hearings in stacked relation and spaced substantially equidistant from the anode electrode of the electroplating appa' ratus'when the fixture is immersed in the plating bath, thereby facilitating the even and uniform distribution of the plate to be deposited on the concaved surfaces of the bearings.

A further object of the present invention is to provide a fixture as defined above, upon which a plurality of semicircular bearings may easily and quickly be applied, rigidly clamped and as easily and quickly be removed.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred embodiment of the present invention is clearly shown.

In the drawings:

Fig. l is a plan view of the fixture with semi-circular hearings in four stacked tiers clamped thereon.

Fig. 2 is a side view of the fixture, partly in section, taken along the line and in the direction of arrows 2-2 of Fig. 1.

Fig. 3 is a detail sectional view showing the attach ment of a contact clamp to the core of the fixture.

Fig. 4- is a fragmentary perspective view of a modified form of flexible contactor retainer.

Fig. 5 is a side elevational view of a modified form of plating fixture.

Fig. 6 is a plan view of the fixture shown in Fig. 5.

Fig. 7 is a fragmentary sectional view taken along line 77 in Fig. 5.

Fig. 8 is a fragmentary detail view of a holding bracket of the fixture.

Referring to the drawings, the fixture core as illustrated consists of a hollow square structure of sheet metal presenting four side panels 20, 21, 22 and 23, shown in the present drawings to beheld together at each longitudinal edge by corner brackets 24, 25, 26 and 27 respectively. The side panels are substantially as wide as the outside diametral dimension of the semicircular hearings to be placed on the fixture and are at least as long as the combined length of the number of hearings to be stacked edge for edge lengthwise of the panels. In Fig. 2 five bearings constitute a stack on each of the four panels of the fixture core. Although the drawings show the core as consisting of four panels, it may readily be understood that a core may consist of more panels if desirable. Each corner bracket, equal in length to the side panels, has a fiat front face 28 in a plane at right angles to the diagonal passing through the hollow core and two side walls 29 and 35 substantially parallel to the diagonal. The edge portions of the side walls are bent outwardly fiatly to engage a respective side panel to which the corner bracket is attached preferably by welding. Thus the side panels are secured together to form a hollow core. The fiat faces 28 of the respective corner brackets provide' mounting platforms upon which the flexible contact 2,739,l l7 Patented Mar. 20, 1956 clips are attached. The hollow core may'also be formed from a single sheet of metal bent at each of the three corners and welded at the meeting edges to form the fourth corner. In this type of construction the clips are attached directly along the faces of each core panel.

Figs. 2 and 3 show the contact clip 35 as consisting of a rectangular piece of metal preferably of spring bronze the ends of which are formed to provide a contacting sloping face 36 at each end of the clip. Each clip is attached at its center to a corner bracket, preferably by riveting so that the clip is electrically connected to the bracket as well as rigidly secured thereto transversely thereof, whereby each sloping end of a clip extends over a panel attached to the corner bracket carrying the clip. The clips are arranged on the corner brackets so that each engages and clamps the adjacent edges of the two bearings placed against the panels attached to the corner bracket carrying the respective clip. Thus the four clips 35, 35A, 35B and 35C electrically contact and clamp the bearings ill, A, 40B and 40C upon the respective side panels 21, 22, 23 and 26 as shown in Fig. 1. Two ears &3 and 44 formed at the one end of each side panel act as abutments for the first bearing placed upon a respective panel, locating the end on end stacked bearings on each side panel so that each is engaged by a clip 35, the concaved surface of each bearing facing the side panel upon which the bearing is clamped.

Each corner bracket has an arm 5t attached thereto the arms extending toward the center of the core and being secured to an insulating member 51, centrally apertured to permit the anode 54 to extend therethrough and through the hollow core when the fixture is submerged in the plating bath, holding the anode substantially central of the core and equidistant from thebearings carried by the core. A spider 7% formed by arms similar to arms 56 and secured to the respective. corner brackets, carries an insulating block 71, centrally recessed to receive the end of the anode 54. This assists block 51 in keeping the anode coaxial of the core during the plating operation. All surfaces of the fixture, excepting the surfaces of the bearing contacting faces 36 on the clips 35 are coated with an insulating material for preventing plate deposits thereon.

In order that the plate depositing forces from the anode 54 may be directed against the concaved surfaces of all bearings clamped upon the fixture, the side panels 20, 21, 22 and 23 are provided with a plurality of openings 55, one for each bearing clamped upon the side panel. Each opening 55 is centralized longitudinally and transversely of the respective bearing facing it. As shown in Fig. 2, the openings are diamond-shaped with the longer axis extending parallel to the end edges of the respective bearing and the shorter axis parallel to the lateral edges of the bearing. By end edges is meant the edges of the bearings engaging each other while said bearings are stacked against a panel of the fixture. The edges of the openings farthest apart at the vertical center of the openings converge toward the lateral edges of the bearings and therefore restrict the passage of the plate depositing forces as they fan outwardly from the anode toward the lateral edges of the bearings. This is necessary because the areas of the concaved surfaces of the bearings adjacent the lateral edges thereof are closer to the anode than the areas of the concaved surfaces midway between sai lateral edges and therefore the closer areas would receive a heavier plate deposit than the more remote intermediate areas if no control were provided. By restricting the plating forces directed toward the more adjacent bearing areas through the medium of constricted openings, an even plate deposit of uniform thickness is obtained on the concaved surfaces of the bearings facing said openings.

Fig. 1 shows the flexible clips separately formed each attached at its center adjacent a respective bearing and having oppositely disposedflexible portions for engaging the bearings. Fig. 4 shows a modified form of construction in which an elongated single strip of metal has a flat portion 0 with spaced lateral open end slots 61. strip also has a plurality of slits 62 forming flexible fingers 63 shaped similarly to the portions 36 of the single clips of Fig. 1. Two of these strips are placed together so that their slotted portions overlap the fingers 63 extending in opposite directions. The strips are then placed upon the respective corner brackets and adjustably secured thereto by screw bolts passing through the corner brackets and through the aligned slots 61 of the clip strips. Loosening of the screws permits inward and outward adjustment of the strips relatively to the core panels thereby accommodating a smaller or larger diameter hearing to be placed upon the fixture. The screw bolts electrically clamp the clip strips to their respective corner brackets.

The fixture illustrated by Figs. 5 to 8 on the second sheet of drawings is different in construction than the fixture illustrated on the first sheet of drawing. Here the four side panels 80, 81, 82 and 83, rectangular in shape, are secured together at their longer edges in any suitable manner to form a hollow core. stiffening plates 84 are secured at each corner at one end of the core and a centrally apertured bottom 85 is secured in the opposite end of the core. All surfaces of the core are covered with a relatively thin coating of any suitable insulating material not subject to receiving an electroplate. Two brackets, substantially as long as a panel, are adjustably and insulatingly secured to each panel. The bracket 86, attached to panel 83 along one longer side thereof, has a foot portion engaging the panel and an angular portion substantially at right angles to the foot portion. The foot portion has spaced slots through which extend the screw studs 87, anchored to panel 83. Fig. 7 shows one of these screw studs 87 secured to panel 83. An insulating washer 88 is pressed into gripping engagement with the bracket 86 by the operation of the clamping nut 89. The bracket 86 has the onelonger edge of a resilient plate 91 secured to it in any suitable manner, said resilient plate being slotted to form a plurality of fingers 92 which extend from the surface of the bracket to which said resilient plate is anchored, see Fig. 8. the length of plate 91 which is as long as the bracket 86.

Panel 83 has another right angle bracket 93 attached alongside the other edge thereof, said bracket 93 being similar to bracket 86 but does not have a resilient plate providing fingers. Screw bolts 87 extend through elongated slots in the foot portion of bracket 93 and they are insulated by rubber washers clamped upon the bracket 93 by nuts on said screw bolts. Brackets 86 and 93 are so adjusted on panel 83 that they are spaced, one from the other, to receive semi-circular bearings 106 and hold them clamped upon the panel with their concaved surfaces facing the panel as shown in Fig. 6. The resilient fingers 92 press against the outer surface of a hearing, when it is inserted between the brackets on a panel, and clamp the bearing against the plain bracket, thereby securely holding the bearing upon the panel of the core. The plain brackets 94 and 95 secured to panels 52 and 80 respectively have stiff metal straps 96 and 97 attached thereto for supporting a conductor ring 98 to which pig tails 99, connected to the several other brackets on the core panels, are electrically connected. This connects all brackets on all panels together so that all bearings, contacted by the resilient fingers on one bracket of each panel, are electrified for the plating process.

The bottom 85 supports an insulating member 100 which has a recess centrally of the core. Two posts 101 and 102 are anchored to two diagonally opposite stiffening plates 84 and serve as mounts upon which the insulator bar 101 is secured. This bar is centrally apertured to receive the anode 102 which extends centrally through The fingers extend throughout the core and into the recess in member 100. Thus the anode is maintained central of the core and equidistant from each panel thereof. Each panel has a row of holes 105 through which the plate depositing forces, emanating from the anode 102, pass in order to deposit an electroplate of substantially uniform thickness and even distribution upon the concaved surfaces of the bearings 106 facing said holes.

The bearings are easily removed from between adjacent brackets on the core panels and new ones are just as easily inserted therebetween. If bearings of another size are to be placed in the fixture, nuts 89 are actuated to permit the respective brackets to be moved toward or away from each other to accommodate the different size hearing to be plated. The anode is easily removed through a side opening in the insulating block 10% thereby permitting the entire removal of the cathode from the fixture and then the fixture from the plating bath. The rod 108 extending from the cathode may have a hook-like portion by means of which the fixture may be suspended from a supporting conductor over the plating bath in the apparatus.

While the embodiment of the present invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted.

What is claimed is as follows:

1. A fixture for holding a plurality of workpieces to be immersed in a bath for electroplating of the workpieces, said fixture comprising, a hollow core into which an electrode of the electroplating apparatus is adapted to be inserted, said core having a plurality of flat sides secured together at their longitudinal edges, a contact clip secured electrically and mechanically by fastening devices at each corner of said hollow core and extending longitudinally parallel with the respective corner and between which serni-cylindrical bearings are adapted to be inserted so that the bearing edges engage the respective outer sides of the core with their concaved surfaces facing the outer sides of the core, said clips each including a rigid bar portion having edge slots extending trans versely inwardly into the bar for adjustable movement of the clips on the fastening devices parallel to the respective corners and a plurality of flexible fingers projecting from the bar portion angular to the bar portion and substantially normal to the core side adjacent to which the fingers are disposed, all interior surfaces of the core being coated with an electrical insulating material, electrode support means extending transversely across said core at one end thereof and including an insulated mem oer through which an electrode is adapted to extend to position the electrode equidistant from the several sides of the hollow core, said core sides each having openings disposed linearly longitudinally thereof with each opening providing a bearing station and providing for directing of the electroplating forces through said sides against concaved bearing surfaces facing the sides.

2. A fixture in accordance with claim 1 in which the flexible fingers of the respective clips are disposed in parallel arrangement and form opposite sides of a channel to be engaged resiliently by opposite edges of semicylindrical workpieces adapted to be placed therebetween.

3. A fixture in accordance with claim 1 in which the openings in the sides of the core each have a greater dimension transversely of the core side in which the openings are disposed than longitudinally thereof.

References Cited in the file of this patent UNITED STATES PATENTS 741,274 Pritchard Oct. 13, 1903 1,735,909 Rosenqvist Nov. 19, 1929 2,073,679 Brown Mar. 16, 1937 2,500,206 Schaefer Mar. 14, 1950 FOREIGN PATENTS 563,435 Germany Nov. 5, 1932

Claims (1)

1. A FIXTURE FOR HOLDING A PLURALITY OF WORKPIECES TO BE IMMERSED IN A BATH FOR ELECTROPLATING OF THE WORKPIECES, SAID FIXTURE COMPRISING, SAID HOLLOW CORE INTO WHICH AN ELECTRODE OF THE ELECTROPLATING APPARATUS IS ADAPTED TO BE INSERTED, SAID CORE HAVING A PLURALITY OF FLAT SIDES SECURED TOGETHER AT THEIR LONGITUDINAL EDGES, A CONTACT CLIP SECURED ELECTRICALLY AND MECHANICALLY BY FASTENING DEVICES AT EACH CORNER OF SAID HOLLOW CORE AND EXTENDING LONGITUDINALLY PARALLEL WITH THE RESPECTIVE CORNER AND BETWEEN WHICH SEMI-CYLINDRICAL BEARINGS ARE ADAPTED TO BE INSERTED SO THAT THE BEARING EDGES ENGAGE THE RESPECTIVE OUTER SIDES OF THE CORE WITH THEIR CONCAVED SURFACES FACING THE OUTER SIDES OF THE CORE, SAID CLIPS EACH INCLUDING A RIGID BAR PORTION HAVING EDGE SLOTS EXTENDING TRANSVERSEL INWARDLY INTO THE BAR FOR ADJUSTABLE MOVEMENT OF THE CLIPS ON THE FACTENING DEVICES PARALLEL TO THE RESPECIVE CORNERS AND A PLURALITY OF FLEXIBLE FINGERS PROJECTING FROM THE BAR PORTION ANGULAR TO THE BAR PORTION AND SUB-

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