US2422537A - Machine for coating insulators - Google Patents

Description

June 17, 1947. E H, Fl scH R MACHINE FOR COATING INSULATORS Original Filed July 31, 1940 4 Sheets-Sheet 1 73 KrCl/KM ource 42 INVENTPR fuyen'efl' flame June 17, 1947. FlSCHER 2,422,537

I MACHINE FOR COATING INSULATORS I Original Filed July 31, 1940 4 Sheets-Sheet 2 mvzmon Ezzyefiel 723M922 June 17, 1947.

E. H. FISCHER MACHINE FOR COATING INSULATQRS Original Filed July 31, 1940 4 Sheets-Sheet 3 kukkuux an INVENTOR fayene [Y film/zen June 1-7, 1947. HSCHER 2,422,537

MACHINE FOR COATING INSULATORS Original Filed July 31, 1940 4 Sheets-Sheet 4 INVENTOR A ORNEY Patented June 17, 1947 UN IT ED STATE-S PATE OFFICE 2,422,537 MACHINE FOB cos'rmc. nvsumrrons Eugene H. Fischer, Derry, Pa., assignor to West'- inghouse Electric Corporation,.EastBittsburgh, Pa.,.a corporation of Pennsylvania Original application J'uiy 31,, 1940, Serial N0.

348,804. Dividedand thisapplication September 28, 1943, Serial No. 504,126

3 Claims.

The present invention relates to the coating of ceramic bodies and it has particular relation to the application to electrical insulating bodies of coatings which are to cover only a predetermined portion thereof.

This is a division'of' my application filed July 31', 1940, Serial No. 348,80 l', now Patent 2,333,557 whichissued-November 2, 1943.

In the electrical insulatorart, it has become common practice-tapply a conducting coating to portions of insulators, generally in addition to the regular glaze, forsuch purposes as the suppression of radio interference. This conducting coating is applied to the insulator surface atand adjacent to the points of contact with conductors and other metallic parts or members to reduce electrical dis-charge to the insulator surface. The coating material employed is preferably a liquid of the composition described in Hunt U. S. Patent No. 1,973,076, whil further consideration of the principles involved may be found in Patents No. 1,987,683 and No. 1,997,688.

Insulators of the pin-type, for example, are generally provided with a coating of this type at the upper surface to cover the conductor and tie-wire groove portions and also Within the pin hole. For each type and size of insulator, the most efficient and effective extent of the conducting coating is readily determinable. Since application of the coating to any greater amount of the surface results in a Waste of material and may impair the effectiveness of the insulator, the industry has encountered the problem of accurately and uniformly applying this material to theproper surface portion of the insulator in an inexpensive and efficient manner.

According to one embodiment of the present invention, an intermittently driven conveyor is provided to carry insulators placed thereon in sequence to a predetermined stationary position serving asan operating station. A multiarmed member which isintermittently rotated in-synchronism with the conveyor moves downwardly as each insulator reaches this predetermined position and grips it to remove it from the. conveyor. At the same time another arm of me conveyor dips an insulator previously picked up by it to, a predetermined depth in coating liquid disposed in a constant level receptacle disposedelsewhere along the periphery of the rotating member. Thus, the device continuously coats the desired'area of the insulators at a rapid rate and it is only necessaryfor an operator-to place the articles on the conveyor at some point in-its travel and remove them from the rotating member after completion of the coating process. It will appear-evident that the invention is not limited to any particular type of insulator and may be used to coat articles with 2; materials other than the conducting or semiconducting: compound previously described.-

It is accordingly an object ofi'thezpresentinventicn to provide an improved means'for applyir g a. coating to-ceramic bodies.

It is'another; object of the invention to? provide improved apparatus for. coating apredetermined portion of the surface of electrical: insulators.

Otherobjects and advantagesof the invention will-appear from the. following detailed description' taken in conjunction. with; the accompanying drawings lILWhlChI.

Figure 1 is an enlargedview in, vcrticalsection of a type of insulator; treatedinaccordancewith the present invention;

Fig. 2 isa fragmentary" end View invertical section-of the mechanism of the invention;

Fig. 3 is asideview of: the structure shown in Fig. 2;

Figs. l and 4A are; fragmentary views of control devices :used in. the operation of: the invention;

Fig; 5 is anzenlarged viewinvertical'section of a work-holder involved in suchoperation; and

Fig; 6 is .an'. exploded perspective: viewof. the driver of'the apparatus.

The figures of the accompanying drawing correspond to Figs. 3, 6, 4; 5,13, 11 and 12, respectively, of said-Patent 2,333,557 of which thisappli'cation isa division,. andthe. same reference characters are used-.inboth cases.

Inthe drawings :is shown apparatus foritreatzing an insulator l such'i'as. is shown inFig; 1 in accordance with the invention. The embodiment illustrated'is such as iWlll coat the: insulator with glaze overapreterminedarea" of the outer. top surface asatb;

Referring nowv to the: drawing, the apparatus includes a conveyor. comprising a plurality of cars or traysl (Fig. 3.). which" are? pivotally connecte'd'toeach othenby meansaof roller pins 4-to forman end-less. chain-.x For" a detailed description of the construction of the. conveyor, reference may be had to'th'e aforesaidPatent 2,333,-,- 557. The conveyor movesztintermittently; as: described in such patent.

Located near the drivingtend of "the conveyor-is adipping assembly 58% (Fig.3) which" includes a, plurality of angularlyvspaced'arms 6ll attached to an index head 62. whichtis, in turm. supported from a vertical column. indicatedat 64.- The index head. is. adapted; to; operate tin synchronism withth'e conveyor and on the endot each ofthe arms -is disposed-a chnckfifit for:grippingan insulator when it 1 is disposed; at a particular position' of the conveyor. Having; particular refer ence tOFl'gS.-4; Sand 6, theldriving sprocket' I4 is arranged to be driven from a. motor 68 ithrough anintermittent drive includin'gra driving dislc I0 and a fienevw geara 12; Y The -.:-drivingc.disk;n'llris of a key H8.

3 keyed to a driving shaft I4 which is driven by the motor and includes a driver pin I6 for engagement between the spokes of the Geneva gear as shown, it will be evident that its shaft will be rotated through of a revolution for each to intermittently drive a shaft 18 to which it is f attached. With a Geneva gear having 5 spokes,

revolution of the driving disk/ Likewise, the

to bring each of them, in turn to a, predetermined stationary position.-

Attached'to one side of the driving disk in is a cam shoe 32 while a cam pints extends further out from the leading edge of this cam shoe. The

. cam shoe and cam pin are disposed to engage the cam followers 42 and 44,.respectively to actuate the push rods 38 and 48 in synchronism with the movement of the conveyor.

As is best shown in Fig. 2, the vertical column 64 for the dipping mechanism is secured at its bottom to a metal flange 86 which is in turn attached by any suitable means to a base member 88. Disposed within the lower end of this column is a metallic base member 80 having a recess 92 within which is seated the lower end of a cylindrical body 94. A cylinder bonnet 98 having an opening 98 through which a main vertical shaft I00 extends is disposed on the upper end of the cylinder while suitable packing means I02 surrounds the shaft at this point. A piston member I34 is secured to the lower end of the shaft I00 to fit snugly within the cylinder while an air-pressure pipe I36 communicates with the bottom of the cylinder at a point below the lowermost travel of the piston. The index head 62 is secured to the shaft I88 in a vertically adjustable position between nuts I01 engaging the screw threaded upper end thereof.

Located within the upper end of the vertical column 6 3 is a top bearing support I08 which carries a bushing IIU for engaging the shaft I08. A central bearing support H2 is disposed in the vertical column intermediate the ends and also includes a bushing I I4 for engaging the shaft I08. A bevel gear H8 is attached to the shaft I08 at a point above the central bearing support by means This key fits into a longitudinal slot I20 in the shaft I80 so that the shaft itself may be moved vertically upward while the gear H6 remains stationary. The gear is held in the stationary-position by means of a bearing spacer 266 which communicates with the interior of the arms 60 as well as with tubular members 268 which lead to a vacuum pump or tank, as indicated. On the end of each of the arms, there is disposed a tubular casing 210 which is secured thereto by means of bolts 212 while an apertured bafile member 214 extends therebetween. A cap portion 216 is fitted over the top of the casing in sealed relationship while a bushing 218 is centrally arranged within it. Within the bushing is located a tubular shaft 280 which is slidably arranged within the casing and includes an I axial opening 282 communicating with a radial opening 284. The radial opening is arranged to communicate with the'interior of the arm 60 through apertures in the casing and bushing when the shaft 280 is in an upward vertical position.

To the lower end of the shaft 280 there is secured a horizontal plate 286 to which is cemented a soft rubber pad 288. An aperture is provided in the pad 288 to permit communication of vacuum with the interior of the insulator I engaged thereby. A compression spring 290 is disposed" around the shaft .280 between the member 288 and a bottom member 292 attached to thecasing 210. In addition, collars 294 and 296 are secured to the shaft 280 to limit respectiv ly the downward and upward motion thereof. I

A bracket member 298 is secured to the casing,

as indicated, in order to pivotallysupport an operating lever 388. tween the casing and the operating lever to bias the lower portionof the lever including prong Silt inwardly. The prong SM is adapted to enbeing biased inwardly, grips the flange 386 or I22 which engages the top bearing support at its upper end and is secured at its lower end to a collar member I24. This collar member I24 engages the gear IIB through a bearing I26.

It will be seen that this gear H6 is engaged by another bevel gear I28 which is secured to a shaft I29. As described in the aforesaid patent, the shaft I29 is driven from the shaft I8 of the conveyor which carries the Geneva gear 72 (Fig. 3 hereof). In addition,- a sprocket wheel I38 is secured to the driving shaft 14 and engaged by a chain I32 to drive another sprocket member 134. The sprocket I34 is keyed to a shaft I36 which has a cam I38 (Fig. 4 hereof) at its other end for operating a valve M0 for controlling the admission of air to the pipe I06 to raise and lower the shaft IBIL H Referringto Figs. 2 and 5; it will be seen that one of the grooves 398 therein to lock the shaft 280 in communication with the vacuum source after the chuck unit is moved upwardly and thus hold the insulator thereon. To'release the article, it is only necessary to push inwardly on a knob 3H) on the operating lever to permit the spring 23!] to force the shaft 288 out ofcommunication with the vacuum source;

At a predetermined position along the path of rotation of the arm 69 is, disposed a receptacle 3 !2 for glazing fluid. This receptacle is provided with annular overflow chamber indicated at 3M from which fluid may be removed by means of a tube 3% to maintain'co-nstant the level in the receptacle. At the same time, theinteriorpassage of a tubular supporting member 323 com municates with the interior of the'recepta'cle 3i2 to permit the pumping of additional fluid into it from the bottom. In order to prevent undue agitation of the fluid, a baffie plate 322 is disposed; over this lower entrance. Th support 326 is screw threaded and secured within a bracket 3% attached to the stationary part of the apparatus so that the vertical position .of'the receptacle may readily be adjusted.

The control of the valve I40 for causing vertical movement of the shaft I30 and index-head 62 will be readilyrunderstood upon referenceto A spring 392 is'disposed be- 34 has another passage connected with a compressed air source through a pipe 326. The remaining passages are closed by a plug 328 and open to th atmosphere, respectively. An operating link assembly for the valve is pivoted about a fixed point 330 and connected to a spring 332 to bias a pin 334 thereon against the surface of the cam. In the embodiment shown the pipe I06 is open to the atmosphere when the pin 334 engages the lower cam surface and is connected to the air pressure pipe 326 when the pin bears against the raised surface of the cam.

In operation, the dipping mechanism is in its downward position as shown in Figs. 2 and 3 so that an insulator on one of the chucks 66 is being dipped to a predetermined depth in the receptacle 3l2. Under the control of cam I38 (Fig. 4), the raised portion thereof engages the pin 334 causing the valve I40 to permit the passage of compressed air into the bottom of the cylinder 94 to raise the index head 62 of the dipping mechanism upwardly and withdraw the insulator from the receptacle 3l2. At the same time another chuck 66 lifts from the conveyor an insulator which it engaged while the index head 62 was lowered to its down position.

As described in the aforesaid patent, the conveyor-then advances one step and during such :movement the now elevated index head rotates one step to brin another chuck 66 to a position 'directly above another insulator on the conveyor; moves the just lifted insulator into dip- "ping position; and moves the dipped insulator :away from the dip-tank.

While the driving pin 16 is out of engagement with the Geneva gear the lower portion of the cam I38 engages the pin 334 causing the valve 140 to connect the pipe I06 to the atmosphere. The index head 62 then drops to its lower position in which the chuck positioned directly over the insulator on the conveyor engages it and the insulator gripped by the chuck directly over the receptacle 3l2 is dipped therein.

It will appear evident that the apparatus may be readily adapted to handle articles of various different sizes. The position of the index head 62 on the movable shaft I00 may be adjusted by means of the nuts [0! while the vertical position of the glaze tank may be changed through the medium of the bracket support 324. Different sized adapters may be used in the holder units and, if desired the size of the holders themselves may be changed. The chuck units 66 readily accommodate themselves to slight variations in insulators of the same general size because of the grooves 308 thereon. The speed of operation is controllable in a simple manner while the various cams may bedesigned to provide the most desirable operating cycles.

While only one of the holes I42 in each tray is shown provided with insulator holders and only a single dipping mechanism 58 is employed, it will be evident that this and the pin coating mechanism may be duplicated to simultaneously treat two rows of insulators. It is also within the scope of the invention that electrical timing and solenoid equipment may be substituted for the mechanical cam arrangements shown to properly control the cycle of operation.

Since these and numerous other modifications may be made without departing from the spirit and scope thereof it is intended that the invention be limited only by the appended claims interpreted in view of the prior art.

I claim as my invention: 4

1. Coating apparatus comprising a rotatable member, a support therefor, a plurality of angularly displaced means on said member for holding articles to be coated, means for intermittently rotating said rotatable member to successively bring each of said holding means to each of a pair of predetermined stationary positions with one of said holding means at each of said positions at each stop, means for moving an article to a position under a holding means at the first said predetermined position, a receptacle for holding liquid coating material to a predetermined depth under a holding means at the second said predetermined position, means for automatically lowering said rotatable member a predetermined amount while in each of its stationary positions to cause the holding means in said first predetermined position to contact and grip an article and the holding means in said second position to dip an article thereon to a predetermined depth in said receptacle.

2. Coating apparatus comprising a rotatable member and a support therefor, a plurality of equally spaced arms disposed radially from said rotatable member, a holding member on the under side of each of said arms, said holding member being capable of gripping a ceramic article upon being brought into contact therewith, means for intermittently rotating said rotatable member to successively bring each of said arms to each of a pair of predetermined stationary positions spaced apart by a multiple of said arm spacings, a receptacle located at said second predetermined position for holding liquid coating material to a predetermined depth, means for automatically lowering said rotatable member and arms a predetermined amount with arms in said predetermined positions to cause the holding means on the arm in said first position to contact and grip a ceramic article thereat and to dip a ceramic article on the arm in said second position to a predetermined depth in the material in said receptacle.

3. Coating apparatus comprising a substantially horizontal rotatable member, a plurality of article holders mounted in an annular series on said member, said article holders being designed to grip an article upon engagement therewith, means for intermittently rotating said member to bring each of said holders in sequence to each of a pair of angularly displaced predetermined positions, means for supporting an article to be coated at the first of said predetermined positions, a receptacle for holding liquid coating material at the second of said predetermined positions, and means for relatively moving said rotatable member and said supporting means while a holder is in said first position to cause it to grip an object thereon and for relatively moving said rotatable member and said receptacle while a holder is in said second position to dip an article thereon to a predetermined depth in said receptacle.

EUGENE H. FISCHER.

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

UNITED STATES PATENTS Number Name Date 2,272,586 Ross Feb. 10, 1942 2,275,382 Smith Mar. 3, 1942 2,333,557 Fischer Nov. 2, 1943

Images