US2595681A

US2595681A - Plating point assembly for electroplating racks

Info

Publication number: US2595681A
Application number: US93968A
Authority: US
Inventors: Elmer E Liles
Original assignee: Individual
Current assignee: Individual
Priority date: 1949-05-18
Filing date: 1949-05-18
Publication date: 1952-05-06
Anticipated expiration: 1969-05-06

Description

y 1952 E. LILES 2,595,681

PLATING POINT ASSEMBLY FOR ELECTROPLATING RACKS Filed May 18, 1949 v 2 SHEETS-SHEET 1 5 fiZZXIZ for .7 'ZZ77Z67 Elzles a; orize s May 6, 1952 2,595,681

PLATING POINT ASSEMBLY FOR ELECTROPLATING RACKS Filed May 18, 1949 2 SHEETS-SHEET 2 Patented May 6, 1952 UNITED STATES PATENT OFFICE PLATING POINT ASSEMBLY FOR .ELECTROPLATING RACKS 'Elmcr E. Liles, Harvard, Ill.

ApplicationMay 18, 1949, Serial No. 93,968

8 Claims. 1

This invention relates to a plating point assembly forelectroplating racks,.and in particu- ,jacket is meant a covering which is not damaged by the acid or alkaline baths used in electroplating, and which is not subject to electrochemical action.

The racks on which objects arehung for electrcplatingmust be of metal, and must be provided with plating points on which may be hung the objectsbeing plated. Theracks, the points, and the objects being plated form one side of the electroplating circuit and are connected "to a source or electric current by a buss bar. Thus :they must be in metal-to-metal contact. All of "the rack which is submerged in the plating bath,

lacquered by dipping into a primer, after which it must be baked for approximately one-half hour. After it has been cooled, any blisters in the lacquer must be removed and bare spots touched up. A second priming coat is then applied which Ifurnishes the proper base for adherence of the final protective coating. Following the second priming coat, the rack is baked for at least twenty minutes and preferably longer. The 'final protective dielectric coating is a liquid which is in a tank at room temperature. The rack, hot from the oven, is dipped into the protective dielectric which adheres to it in a coating, the thickness of which depends upon the temperature of the rack when it is immersed in the coating material. After the rack has stood for about one-half hour to permitthe coating to set in a preliminary way, it must be baked at 365 for a period of one to one and onehalf hours to finally set the protective coating. Thus, it is seen that application 'of the protective dielectric coating to an electroplating rack occupies upwards of half a days time, and involves a considerable amount of handling and use of high temperature ovens.

Heretofore there has been no assembly by which the plating points could be removably secured in electric contact with the rack, and in which the contact elements were covered by a protective dielectric material. The points have commonly been welded or screwed to studs on' the rack, and the entire assembly coated as described above. The points, especially those used for plating heavy parts such as automobile grilles and bumpers, are subject to breakage, and when a point broke it was necessary to take the entire rack out of service and strip the coating therefrom, weld, or screw on a new point, and recoat the rack and points.

The principal object of my invention, therefore, is to provide a sealed assembly inwhich a plating point may be secured, and in which a broken point may be readily replaced without disturbing the protective dielectric coating on the rack.

A further object is to provide such anassembly in which the parts are inexpensive and may be readily assembled.

Yet another object is to provide such an assembly in which the plating point is g ipped 'to prevent rotation.

The invention is illustrated in a preferred em bodiment in the accompanying drawings in which:

Fig. 1 is a sectional view of an electroplating tank with a typical rack in place therein;

Fig. 2 is a section taken as indicated at the line 2-2 of Fig. l;

Fig. 3 is a section taken as indicated at, the line 33 of Fig. 2;

Fig. 4 is a vertical central sectional view of the core; Fig. 5 is a section taken as indicated at the line 5-5 of Fig. 2;

Fig. 6 is a side elevation, partially in section, of the bottom segment of the protective dielectric shield means; and

Fig. 7 is a section taken as indicatedat the line 'l-l of Fig. 1.

Referring to the drawings in greater detail, an electroplating tank I 0 is provided with a buss bar H which is connected to a source of electric current (not shown). Hung from the buss bar II is an electroplating rack, indicated generally at I2, which takes the form of a rectangular frame l3 with a hook l4 at its upper end by which it may be hung on the buss bar. A plurality of electroplating point assemblies, indicated generally at l5, are secured to the rack 12. As best seen in Fig. 7, all submerged portions of the electroplating rack are covered by a protective dielectric coating I6.

As best seen in Figs. 2 and 4, each plating point assembly 15 comprises ahollow cylindrical metal core l1 having a flange l8 forming a base at its lower end. The upper surface of the base I8 is annularly grooved at l9. In securing the plating point assembly |5 to the rack I2, the base I8 is preferably welded, brazed or soldered to the rack prior to the application of the protective dielectric coating l6, although any means providing firm metal-to-metal contact is satisfactory. A temporary cap is placed over the core I1, and the dielectric coating is applied to the rack and to the bases l8 of the plating point assemblies l5. The annular groove I9 in the base l8 provides a footing for the coating |6 so that there is little tendency for the coating to slide or be pressed away from the side wall of the core H when the assembly is completed.

The core I1 is transversely slotted at 20, and the upper portion of the core I! is both internally and externally threaded. A cup-like member 2| (illustrated in Fig. 6) has a central aperture so that it may be dropped over the core l7, and rest upon the coating IE on the upper surface of the base N3 of the core. This cup-like, or flanged annular member 2| forms the bottom segment of rigid protective dielectric shield means which cover the core I! to protect it from the action of acid or from electro-chemical reactions. The bottom segment 2| is slotted at 22, and is placed with the slot 22 alined with the slot 20 in the core.

A metal ball 23 rests in a dimple in the bottom of the core H, and furnishes a bearing surface for a plating point 24 which may be rested in the

registering slots

23 and 22. As best seen in Figs. 2 and 3, the plating point is a metal tube or rod which is covered with a dielectric jacket 25 throughout its entire area with the exception of the central portion 26 which is in contact with the metal ball 23, and its tips 21. The dielectric jacket 25 fits snugly within the

slots

23 and 22,

so that a sealing contact may be effected between the jacket 25 and the bottom segment 2| of the dielectric shield means.

A threaded plug 28 screws into the internal thread of the core I! in order to lock the plating point 24 firmly against the metal ball 23, to provide gripping means by which the plating point 24 is prevented from rotating in the

slots

23 and 22 when any heavy object is hung on the point.

A rubber washer 29 overlies the upper end of the bottom segment 2|, and a protective ring 33 surmounts the rubber washer 29. A threaded metal nut 3| screws onto the external thread of the core H and may be screwed tightly against the protective ring 33 so as to compress the rubber washer 23 and the soft coating 25 on the plating point and effect a tight seal of all the marginal junctures of the several members. A second washer 32 of insulating material capable of adapting its shape to any irregularities in the abutting surface of the protective ring 30 or the cap 33 preferably is placed on top of the protec tive ring 30 surrounding the nut 3|. The protective dielectric shield means is completed by an inverted cup-shaped cap 33 which is internally threaded for attachment to the core by screwing onto an external thread on the nut 3|. The cap 33, together with the protective ring 30 forms the top segment of the protective dielectric shield means.

The nut 3| is provided with a kerf 3 la on each of its surfaces. The kerf on the lower surface is provided in case slight seepage of electroplating liquid should cause the cap 33 to freeze to the nut 3|. In that event, the rubber washer 32 could be cut out and a tool inserted in the lower groove 3|a so as to remove the nut 3| and the cap 33 as a unit.

Preferably the outer surface of the cap 33 is knurled to provide a gripping surface for screwing the cap down tightly upon the Washer 32, and if desired a conventional retaining spring may be inserted between the cap 33 and the nut 3| to lock the cap 33 in its sealed position.

It is understood, of course, that the dielectric jacket 25 on the plating point is ordinarily formed of fairly soft rubber as are the Washers 29 and 32, so that they may conform themselves to the adjacent rigid portions of the assembly in order to effect a tight seal.

The foregoing detailed description is given for clearness of understanding only, and no unnecessary limitations should be understood therefrom, as variations will be obvious to those skilled in the art.

I claim:

1. A contact assembly to receive a plating point on an electroplating rack, comprising: an externally threaded cylindrical metal core having a base for metal-to-metal attachment to an electroplating rack and to receive a protective dielectric coating which also covers said rack, said core being transversely slotted to receive a dielectric jacketed metal plating point and make electric contact with an unjacketed portion thereof; a removable, annular protective, dielectric shield bottom segment surrounding the lower portion of the core and having a slot in register with the transverse slot in said core, said bottom segment being constructed to seal against a coating which covers said rack and the base of said core and the slot therein being constructed to make a snug sealing fit with the dielectric jacket on a plating point; and a removable protective dielectric shield top segment surrounding the upper portion of the core, said top segment being threaded for attachment to the core and having a lower portion to make sealing engagement with the bottom segment and with the dielectric jacket on a plating point.

2. A contact assembly according to claim 1 wherein the lower portion of the top segment is a separate annular member and is held in sealing engagement by a threaded nut, and the top segment is attached to the core by screwing onto an external thread on said nut.

3. A contact assembly according to claim 1 wherein the core is hollow, and gripping means are provided in the core to prevent twisting of a plating point in the transverse slot.

4. A contact assembly according to claim 1 wherein the metal core is internally threaded to receive a threaded metal plug which holds a plating point firmly in the slot of the core.

5. A contact assembly to receive a plating point on an electroplating rack, comprising: a metal core having a base for metal-to-metal attachment to an electroplating rack and to receive a protective dielectric coating which also covers said rack, said core being constructed to loosely receive a transversely extending dielectric jacketed metal plating point; attaching means cooperating with said core to grip said plating point and make electric contact between said core and an unjacketed portion of said plating point; a removable dielectric shield bottom segment to seat upon and seal against the dielectric coating which covers said base and said rack, said bottom segment having an upwardly facing groove to make a snug sealing fit with a portion of the perimeter of the dielectric jacket on a plating point; and a removable dielectric shield top segment capping the core and adapted to seal against said bottom segment and against the re mainder of the perimeter of the dielectric jacket on a plating point.

6. A contact assembly according to claim 5 wherein the core is externally threaded, the shield bottom segment sits loosely upon the dielectric coating which covers the base and the rack, the shield top segment includes a separate annular lower portion which seats on the bottom segment, a threaded metal nut screws onto the core overlying the annular lower portion of the top segment, and the upper portion of the top segment seals against said lower portion.

7. A contact assembly according to claim 6 wherein soft dielectric washers are interposed between the bottom segment and the lower por tion of the top segment, and between the two portions of the top segment.

8. A contact assembly to receive a plating point on an electroplating rack, comprising: an uninsulated, metal core having a base for metalto-metal attachment to an electroplating rack and to receive a protective dielectric coating which also covers said rack, said core being constructed to loosely receive a transversely extending dielectric jacketed metal plating point; attaching means cooperating with said core to 3 grip said plating point and make electric contact between said core and an unjacketed portion of said plating point; a removable dielectric shield bottom segment to seat upon and seal against the dielectric coating which covers said base and said rack, said bottom segment having a slot to make a snug sealing fit with the dielectric coating on the plating point; and a removable protective dielectric shield top segment surrounding the upper portion of the core, said top segment being constructed for attachment to the core and having a lower portion to make sealing engagement with the bottom segment.

ELMER E. LILES.

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

UNITED STATES PATENTS Number Name Date 1,054,920 Lovejoy June 17, 1913 1,521,592 Belke Jan. 6, 1925 2,094,392 Winslow Sept. 28, 1937 2,097,324 Hill Oct. 26, 1937 2,195,630 Pa-pp Apr. 2, 1940 2,439,190 Schroeder Apr. 6, 1948 FOREIGN PATENTS Number Country Date 353,147 Germany May 12, 1922 542,766 France May 22, 1922