US2697689A

US2697689A - Combination barrel and rack electroplating apparatus

Info

Publication number: US2697689A
Application number: US175104A
Authority: US
Inventors: Solomon E Barr; Cyrus I Knecht
Original assignee: Western Electric Co Inc
Current assignee: AT&T Corp
Priority date: 1950-07-21
Filing date: 1950-07-21
Publication date: 1954-12-21
Anticipated expiration: 1971-12-21

Description

S. E. BARR EI'AL.

Dec, 21, 1954 COMBINATION BARREL AND RACK ELECTROPLATING APPARATUS 4 Sheets-Sheet 1 Filed July 21, 1950 INVENTORS $.E.BARR

. (LL/(N CH7 ATTORNEY Dec. 21, 1954 s. E. BARR ETAL 2,697,689

COMBINATION BARREL AND RACK ELECTROPLATING APPARATUS Filed July 21, 1950 4 Sheets-Sheet 2 mveurops" $'.E.BARR

c./. scar BY 9 ATTORNEY 1366- 1954 s. E. BARR El'AL COMBINATION BARREL AND RACK ELECTROPLATING APPARATUS 4 Sheets$heet 3 Filed July 21, 1950 mvsurons $.E8ARR E.

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217' TORNE Y 1386- 1954 s. E. BARR EI'AL COMBINATION BARREL AND RACK ELECTROPLATING APPARATUS 4 Sheets-Sheet 4 Filed July 21, 1950 w L m M I N V E N TORS s. E. BAR)? *2 c. KNECHT MMA A 7' TORNE V United States Patent f COMBINATION BARREL AND RACK ELECTRO- PLATING APPARATUS Solomon E. Barr, Elizabeth, and Cyrus 1. Knecht, Westfield, N. J.; said Barr assignor to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application July 21, 1950, Serial No. 175,104

1 Claim. (Cl. 204-222) This invention relates to electroplating apparatus and.

more particularly to apparatus of this type which is adaptable to more than one method of electroplating.

In one main type of electroplating equipment, a tank is provided for containing the electrolytic solution, with means for holding the articles to be plated being mounted on the tank or otherwise held in operative relation. These means may take the form of a perforate barrel for containing the articles to be plated, the axis of the barrel being at an angle to the horizontal, and the barrel being rotatably suspended in the electrolytic solution and provided with a suitable drive. These means may also take the form of a rack laid across the top of the tank, with the rack having cathode rods for suspending parts in the electrolyte, these cathode rods having means provided to reciprocate them or otherwise agitate them with respect to the solution.

The barrel type construction is adaptable to many types of plating applications, particularly where the parts to be plated are small and many in number. However, the rack type construction provides a more eflicient plating action, and is also more suitable where the parts to be plated are large.

In many industrial concerns, plating requirements are not great enough to justify separate barrel and rack plating units, and the plating schedules in these cases had to be adjusted to whichever type unit could be used to greater advantage. There has been a need in the industry for electroplating apparatus which would be adaptable to both the barrel and the rack type units, and it is therefore an object of this invention to provide electroplating equipment which can be used for either type of plating.

Applicant accomplishes his object according to the invention of making the barrel and the rack type units easily removable and interchangeable, and by providing camming means on the same shaft that drives the barrel unit, said camming means coacting with a rack when the lattfir is in position to reciprocate the cathode rods of the rac Other objects and advantages will be apparent from the following detailed specification taken in conjunction with the attached drawings in which:

Fig. 1 is a side elevational view of the electroplating apparatus with the barrel type unit;

Fig. 2 is a rear elevational view of the apparatus showing the driving and reciprocating means for the barrel and rack type units;

Fig. 3 is a perspective view of the rack type unit prior to mounting on the main tank;

Fig. 4 is a top plan view of the rack type unit in position in the main tank.

With reference to Fig. 1, a tank 11 is used for containing an electrolytic solution for use in the electroplating process. This tank, which is fioor mounted, may be of any suitable shape, but is shown in the drawings as a rectangular structure. solution contained in the tank is not pertinent to the present invention and requires no further discussion.

Mounted in relation to the tank 11 is a barrel shaped container 12 for containing parts to be plated. A container of this type is of especial value when the parts to be palted are small and numerous. The barrel and tank combination shown is similar to that disclosed in Patent 1,936,382 issued November 21, 1933, to J. T. Daniels, and a detailed discussion of its construction is given in that patent. However, in general, the barrel is cylindrical a d is made of a material which not affected by The nature of the electrolytic 2,697,689 Patented Dec. 21, 1954 the electrolyte. It is open at one end for loading and discharging purposes, and its sides are perforated to allow the parts to come into contact with the electrolytic solution.

The barrel 12 is pivotally mounted in bosses 15 located at the top of the tank, by a shaft 14 mounted on the side of the barrel and transverse to its main axis. The barrel has a pair of bracket arms 16 connected to the shaft 14 at one end and a bracket arm 17 connected to the shaft 14 at its other end. These bracket arms, which are rigid with the barrel, serve also to support the main axial shaft 20 of the barrel. In Fig. 1, the barrel is shown in two' possible positions, a driving position in which the barrel is suspended in the electrolytic solution, and a second unloading position, shown in broken lines, in which the open end 21 of the barrel is facing generally downwards to facilitate the unloading operation. The barrel also has a third loading position in which it is approximately vertical with the open end facing up. Since the barrel is top heavy at its open end with respect to its pivotal shaft 14, it is held by gravity in both its driving and unloading positions. The barrel is held in its loading position by a spring return bar (not shown) on which the barrel frame rests and which is kept in a holding position by the weight of the barrel. Any suitable handle may be mounted on the barrel to aid in moving it to its several positions.

At the open end of the barrel, the shaft 20 is extended and has rigidly mounted at its end a worm wheel 24. This worm wheel meshes with a worm 25 integral with or rigidly connected to a driving shaft 26. The driving shaft 26 is mounted on a bracket 27 located at the back of the tank as shown in Fig. 4 and is driven by a suitable motor 28 through a coupling 29, the motor being mounted on a support 30.

The barrel structure is easily removable from the tank 11 by lifting the shaft 14 out of the bosses 15, which are open at the top. In the operation of the structure as shown in Fig. l, thebarrel is placed in position on the tank and is moved to its loading position, where it is filled with parts to be plated. It is then pivoted about the shaft 14 until the worm wheel at the end of the central shaft 20 is in firm engagement with the worm 25. When the barrel is in this position, most of its interior will be submerged in the electrolytic solution. The driving motor 28 is then started, which rotates the shaft 20 through the worm and worm wheel driving connection. This rotation of the barrel causes a constant moving and shifting of the parts to be plated within the barrel and also agitates the electrolytic solution to insure an even plating.

When it is desired to electroplate by using a moving rack type unit, the barrel unit is lifted from its bosses 15 and a rack type unit such as shown in Fig. 3 is placed in position on the tank.

With reference to Fig. 3, the rack unit comprises a pair of

end parts

34 and 35 which are held in spaced relation by a U-shaped anode bar 36 rigidly connected at one end to part 34 and connected at the other end to a plate 37 mounted on the part 35. Each end part also has a pair of bearing blocks 38 located at the extremities thereof, with the corresponding blocks on the two parts having aligned bores 39. A pair of cathode rods 40 are slidably positioned in the bores 39.

A pair of springs 41 are placed over the cathode rods at one end thereof. These springs are held from movement in one direction by means of washers 42 and pins 43, the pins being fixed with respect to the rods 40, and are held against movement in the other direction by the bearing blocks 38. The ends of the cathode rods 40 opposite to the ends fitted with the springs 41 are provided with circular heads 44.

When it is desired to use the rack type unit, it is placed in position over the top edges of the tank 11 as shown in Fig. 4. Flange members 45 rigid with end part 35 fit over one top edge of the tank while flange members 46 fit over the opposite side. Thumbscrews 47 are used to tighten the rack assembly as required.

It will be seen from Figs. 1 and 2 that a pair of cams 50 are rigidly mounted on the same shaft 26 that mounts the worm 25. Rotation of the shaft 26 by the driving motor 28 will then rotate the two earns 50. When the rack type unit is mounted on the tank, it is positioned so that the two circular heads 44 are aligned with the camming members 50. Any rotation of the shaft 26 will therefore cause the camming members 50 to co'act with the circular heads 44 and reciprocate cathode rods '40 within their bores 39, the actuating movement being against the tension of the springs 41. Reciprocation of the cathode rods will cause agitation and circulation of the electrolyte and will insure even plating of articles which have been suspended from the cathode rods.

The use of camming means to effect the reciprocation of the cathode rods is one of the features of the invention. By appropriate shaping of the cam surface, the return speed of the rods may be varied to any suitable value. For example, it is often desired to have the rods return instantly from their outwardly urged positions, with a snapback action to remove gaseous products clinging to the surfaces of the articles to be plated. This can easily be accomplished with applicants camming apparatus.

A yoke 55 is provided on the mounting bracket 27 to aid in positioning the two different units. When the barrel type unit is used, its shaft 20 is held within the prongs of the yoke, while a pin 56 is mounted on the plate 37 to align the rack assembly with the yoke when the latter type unit is used.

Figs. 1 and 4 show a pair of fixed anode bars 52 having an anode 53 suspended therefrom. These two permanent anode bars are used with both the barrel and rack units, with the latter providing an additional anode bar 36 when it is placed in position on the tank.

The electroplating apparatus here shown would use a conventional current supply and controls. In this connection, the terminals connecting the cathode to the negative side of the supply are positioned with respect to the barrel and rod assemblies to make suitable contact with either unit. This feature avoids the necessity of using a separate set of terminals for each of the two type units.

It will thus be seen that applicants, by mounting camming means on the same shaft that rotates the barrel type unit, have made it possible for either barrel or rack type units to be used with the same apparatus.

This dual purpose is facilitated by making the barrel and rack units easily removable and interchangeable.

It should be noted that the invention described is not limited to any particular kind of plating but is applicable to the electroplating art in general.

It is to be understood that the above described arrangements are simply illustrative of the application of the principles of the invention. Numerous other arrangements may be readily devised by those skilled in the art which will embody the principles of the invention and fall within the 'spirit and scope thereof.

What is claimed is:

Electropl'ating apparatus comprising an open top tank, a rotatable drive shaft extending longitudinally of the top and journalled to one side of said tank, a motor for rotating said drive shaft, a pair 'of spaced cams secured to said drive shaft, a removable frame resting on the top of said tank, means for securing said frame to said tank against lateral movement, a pair of aligned bearings on said frame in alignment with each of said earns. a cathode rod mounted for longitudinal movement in each said pair of bearings and extendingperpendicular to said shaft, spring means biasing each of said cathode rods into engagement with one of said cams, whereby the rotation of said drive shaft and said cams secured thereto causes reciprocation of said cathode rods against the biasing of said springs, an anode rod fixed to said frame between said cathode rods and parallel thereto, and anode rods secured to said tank and extending parallel to and on opposite sides of said cathode rods from said anode rod fixed to said frame.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 628.1686 Boissier July 11, 1899 1,795,336 Hansen Mar. 10, 1931 1,936,382 Daniels Nov. 21, 1933 2,505,531 Ellwood a Apr. 25, 1950 FOREIGN PATENTS Number Countr Date 4,415 Great Britain Feb. 28, 1899