US2915859A - Spray gun mover - Google Patents

Description

W. C. BURT SPRAY GUN MOVER Dec. 8, 1959 4 Sheets-Sheet 1 Filed D90. 2, 1958 Dec. 8, 1959 w. c. BURT 2,915,859

SPRAY GUN MOVER Filed Dec. 2, 1958 4 Sheets-Sheet 4 I f 26 v 46 40 INVENTOR.

@M, M, @ay 3 ATTORNE'Ya M/ILL/AM C. Bunr United States Patent "cc SPRAY GUN 'MOVER William c. Burt, Olean, N.Y., assignor to Clair Manufacturing Co., Inc., Olean, N.Y.

Application December 2, 1958, Serial No. 777,790 6 Claims. (Cl. 51-263) This invention relates to machines for polishing, buffing, glazing and burnishing or the like, as are useful in the finishing of metal, plastic, wooden or other surfaces. More particularly, the present invention relates to improvements in means for moving the spray guns which distribute the liquid polishing and bufling compounds over the surfaces of the glazing or polishing or buffing rolls. The invention specifically applies to straight line reciprocating type spray gun installations.

.The present invention contemplates an improved control of the gun spray operations in relation to the gun movement cycle so as to prevent overloading of the sprayed surfaces at the ends of the gun traivel path. Thus,

one of the objects of the present invention is to provide improved means for controlling the motions of a straight line reciprocative spray gun and to control the spraying operation of the gun so as to insure uniform coverage of the treated surface despite necessary reversals of direction and changes of pace of the gun travel incidental to its reciprocation. I

Another object of the invention is to provide in devices of the character aforesaid improved means for adjusting the mechanism to suit different performance requirements,

Other objects and advantages of the invention will appear in the specification hereinafter.

In'the drawing;

Fig. l isa front perspective view of a polishing or glazing machine of a type such as is used in the cutlery polishing and glazing industries, having mounted thereon an abrasive spray gim mounting and moving and control mechanism of the invention;

Fig. 2 is a front elevation, partly in section, of the gun carriage and control component of the machine;.

Fig. 3 is-another view corresponding to Fig. 2 but with the front cover removed and interior parts shown in section; s

Fig. 4 is'a wiring diagram of the control system;

Fig. 5 is a fragmentary section taken on line V-V of Fig. 2;

Figs. 6, 7 areenlarged scale sectional views of the gun spray control valve'mechanism, showing the valve respectivelyin different conditions of adjustment;

Fig. 8 is a diagram of the pneumatic system of the machine; and p I Figs. 9-12 are schematic diagrams of the machine control system,at different phases of the gun movement and spray control cycle.

As stated hereinabove, the present invention relates to means for moving and controlling operation of a spray 2,915,859 Eiatented Dec. 8, 1959 gun or the like in conjunction with straight line reciprocative distribution of the spray gun output upon the polishing or buffing rolls or other surfaces to be treated thereby. The invention is of course applicable to any industry but by way of exemplification herein it is illustrated and Will be described in detail hereinafter in conjunction with machines employing paired polishing or bufiing rolls between which articles of manufacture are passed for finishing operations thereon while suitable polishing or bufiing abrasive materials are fed by a gun or guns onto the machine rolls. Thus, as shown in Fig. 1, a machine for such purpose may employ parallel polishing or bufiing rolls 14-14 driven by a mechanism as shown at 15 to rotate so as to provide therebetween a polishing or bulfing gap for passage of the work pieces to be surface treated, as are indicated at 16.

Such work pieces may be individually handled or mounted in gangs upon a suitable frame as illustrated at 18, which is usually in turn mounted upon a carriage arranged to reciprocate longitudinally of the rolls. Also, the carriage is mounted for reciprocation in directions toward and away from the polishing gap. Thus, the work pieces will be mounted and-arranged for simultaneous reciprocation in directions longitudinally of the polishing or buffing rolls, and back and forth, in and out of the polishing gap; operative details of a typical machine for this purpose being more fully disclosed for example in US. Patent No. 2,458,708.

Any suitable type gun for spraying the polishing or bufiing compound may be used in the machine of the present invention, and as illustrated for example at 25, Fig. 1, the gun or guns may be mounted on the machine by means of a member 26 constituting at once a mounting support for the guns and a manifold conduit conveying interiorly thereof the air supplies to the gun jets.

Thus, rigid conduits 28-48 extending from the manifold 26 provide adjustable supports for the guns and also convey compressed air to their inlets. The manifold 26 is supported at one end by means of a slide block device 29 and at its other end by means of a valve housing 30; the block 29 and the housing 30 both being in turn slidably mounted upon a cross ,frame 32 supported by machine frame pedestals 3333 to extend transversely of the machine in front view and parallel to the buffing rolls 14. Top and bottom flange plates 34-35 on the frame 32 maintain thewslide block and valve housing in slidable relation on the cross frame 32.

Motions of the gun carriage manifold from left to right on the slide frame 32'are provided for by means of a pneumatic cylinder 40 terminating in headers as indicated at 4244 which are anchored interiorly of the cross frame 32. The cylinder piston as indicated at 46.

sive to pneumatic pressure differentials at opposite sides of the piston 46.

Control of the piston travel in the cylinder 40 is obtained by means of a four-way air valve such as is indicated. at Fig. 3 illustrates the valve arrangement for the cylinder 40 to include ports 56-57 formed in th cylinder head 42, the port 57 being arranged to communicate with the opposite end of the interior of the cylinder through means of a'supplemenital external conduit 58.

Figs. 9-12 illustrate the cylinder and control valve arrangement schematically; .the pneumatic supply connec tion to the control valve being indicated at 59 and the alternatively open vent ports of the valve being indicated at 6060. Thus, it will be appreciated that displacement of the valve spool alternatelyin opposite directions as by means of solenoids 62-64 (Fig. 4.) will shift the valve spool tocause the piston 46 to,reciprocate correspondingly within the cylinder 40. The power supply for the solenoids 62,,64 is illustrated at 66, and the power circuit is arranged to be manually controlled by means of a start-stop foot switch 67 and reciprocation isautomatically controlledtby amicroswitch 68; step blocks 'as indicated at 70 (Figs. 1, 2) being provided on the gun carriage assembly at suitable intervals for alternative actuation of the microswitch 68, thereby reversing the spool of the valve 55 to obtain reciprocations of the gun carriage within the desired travel limits. 7

As illustrated by Figs. 3, 6-12, the piston rod 48 is hollowed as indicated at 72 so as to convey a portion of the air supplied to the right hand side portion of the piston 46 through the piston rod 48 to a connection as indicated at 74 into a conduit 75. This leads through an inlet connection 76'on the housing 30 into the upper end of a vertically extending cylinder bore 78formed in the casing 30 and carrying a piston 80. The piston rod 82 is hollowed intermediately of its ends as indicated at 84 (Figs. 6, 7) and carries at its lower end a shoulder member 86 hearing against a compression spring 88 which is adjustably based at its opposite end by means of a screw adjustable pedestal device 90. Thus, the piston assembly is spring-urged at all times towards its uppermost position in the valve housing, as illustrated for example at Figs. 2, 6, 9, ll.

Interiorly of the housing 30 and slidably surrounding the piston rod device 82 are provided three port spools designated 92, 94, 96, respectively. As shown at 100 the conduit furnishing compressed air for the spray guns connects into the housing 30 at such position as torcommunicate with the lowermost spool 96; while the conduit 52 ,hereinabove referred to carrying a supply of air away from the valve housing to the guns, connects to the housing, at such positionas to communicate with the intermediate port spool 94 (Figs. 6, 7). A vent port for the interior of the valve device is indicated at 102. The wall of the piston rod 82 is apertured as indicated at 104, 106 at such positions thereon to enable the valves to function as follows? Assuming the gun carriage is at the right hand end portion of the machine, for example as indicated at Flgs. 1, 9; upon closing of the manual control switch 67, the solenoid control valve 55 will then be so set as to dellver air pressure into the cylinder 40at the right hand end thereof. This pressure will drive the piston 46 toward the left. At the same time, as illustrated in Fig. 10, compressed air will flow through the hollow piston rod 48 and the conduit 75 and into the upper end of the valve housing 30, thereby depressing the piston 80 downwardly against the spring 88. This motion of the valve piston 80 aligns the compressed air inlet 100 through the aperture 106 in the wall of the piston rod 82, into communication With the compressed air delivery conduit 52 which feeds the gun mounting and air supply manifold 26. Thus, as the gun carriage moves slowly from right to left the guns carried thereon are simultaneously supplied with compressed air so as to spray fromthe guns the polishing orbufiing compound, as the case may be, which materials are supplied to the guns in conventional manner, as through the flexible conduits 110-.111 (Fig. 1).

When the carriage attains its furthermost travelposition toward the left hand end of the machine as shown in the drawings herewith, as determined by the setting of the microswitch block 70, the actuation of the switch 68 reverses the position of the valve 55, thus immediately shutting off the supply of air pressure against the right hand side of the piston 46. As a consequence, the air pressure within the system including the hollow rod 48, the conduit 75, and the valve bore above the valve piston 80 is released, thereby permitting the spring 88 to again move the valve iston 80 upwardly. This action immediately intercomm'unieates' the orts 104 of the valve piston rod 82 with the vent conduit 102, whereby all air pressures interiorly of the valve casing are relieved so that the spring 88 may quicklyrreturn the valve piston to its uppermost position in the valve housing. Thus, the supply of compressed air to the guns is interrupted as the motion of the gun carriage is interrupted at the-end of its travel stroke incidental to reversing .itsdirection and picking up speed to move in its retraction cycle toward the right hand end .of the machine. Reversal of the carriage is of course due to reversal of the valve 55 and supply of compressed air to the left hand end portion of the cylinder 40, as illustrated schematically by Fig. 11.

Fig. 12 illustrates the result of adjustment of the control mechanism so that whenever the gun carriage is moving in its retraction cycle from left to right, the valve housing 30 operates to supply compressed air to the guns, as well as when the gun carriage is movingfrom right to left. This is accomplished by a simple adjustment of the valve orifice at 61 so as to throttle the escape of .air from the right hand end of the cylinder 40 as the gun carriage moves from left to right. This causes a buildup of air pressure within the cylinder whichis in turn conveyed through the housing piston48 andthe conduit to the valve housing 30. This causes the piston therein to be depressed against the action of the spring so as to intercommunicate the air supply 'conduit with the manifold 26 supplying the spray guns. As illustrated at 114 (Figs. 5-7), a pressure relief valve is provided to communicate with. the upper end of the valve bore and housing 30, and is sov arranged as to be opened by pressure thereon of an abutment arm 115 (Fig. 2) extending from the-fixed cross frame, whenever the gun carriage moves into a position of registry of the valve 114 with the member 115. This prevents overspraying by the'guns at the forward end of the stroke.

I claim V v 1. In a machine for bufling or polishing or the like, an abrasive compound spray gun mover mechanism for mounting and moving a spray gun relative to the working rolls of said machine, said gun mover mechanism comprising a carriage mounted upon saidmachine for reciprocation in directions longitudinally of the machine rolls, means mounting spray guns upon said carriage, a pneumatic piston-cylinder device actuating said carriage to reciprocate relative to said machine, carriage motion control valve means adjustable to deliver compressed air alternatively to said cylinder at opposite sides of said piston, means responsive to arrival of said carriage at the limits of the selected travel stroke thereof to actuate said valve means to cause delivery of compressed air alternately to opposite ends of the cylinder, said carriage vbeing connected to the piston rod of saidpiston-cylinderdevice, said piston rod being hollow and open-ended interiorly of said cylinder, a .gun air supply control valve mounted upon said carriage and comprising a, housing having an interior bore accommodating a valve piston, said valve housing bore being at one end in pressure communication with the hollow interior of said piston rod, a compression spring acting against said valve piston biasing it toward said one end of said housing bore, longitudinally spaced apertures extending transversely through.

said piston,-a gun air supply port extending through a wall portion of said valve housing, a: gun air outlet port ex-.

tending through another wall portion of said housing and in communication with conduit means delivering supply air therefrom to the spray guns, the apertures through said valve piston being so positioned and arranged that the gun air supply and air delivery ports of said housing are intercommunicated upon displacement of said valve pistonagainst said spring incidental to passage of compressed air through said hollow rod.

2. In a machine having a buifing or polishing roll, a compound spray gun mover for reciprocating a spray gun lengthwise of said roll, said gun mover comprising a carriage mounted upon said-machine for sliding reciprocation thereon, means for mounting a spray gun upon said carriage, a pneumatic piston-cylinder device actuating said carriage to reciprocate, a carriage motion control valve actuatable to deliver compressed air alternatively to said opposite ends of said cylinder, means responsive to arrival of said carriage at the limits of the selected travel stroke thereof to actuate said valve, said carriage being connected to the piston of said piston-cylinder unit, said piston being hollow and open-ended into one end of said cylinder, a gun air supply control valve mounted upon said carriage and comprising a housing having an interior bore accommodating a valve spool, said valve housing bore being at one end in pressure communication with the hollow interior of said piston, a compression spring acting against said valve spool biasing it toward said one end of said housing bore, longitudinally spaced apertures extending transversely through said spool, a gun air supply port extending through a wall portion of said valve housing, a gun air outlet port extending through another wall portion of said housing and in communication with conduit means delivering supply air therefrom to the spray gun, the apertures through said valve spool being so positioned and arranged that the gun air supply and air delivery ports of said housing are intercommunicated upon displacement of said valve spool against said spring incidental to passage of compressed air through said hollow rod.

'3. In a bufling or polishing machine, a compound spray gun mover for mounting a spray gun relative to the working rolls of said machine, said gun mover mechanism comprising a gun carriage mounted upon said machine for reciprocation in directions longitudinally of the machine rolls, a fluid-pressure actuated piston-cylinder device actuating said carriage to reciprocate relative to said machine, a carriage motion control valve operable to deliver compressed air alternatively to opposite ends of said cylinder upon arrival of said carriage at the limits of the selected travel stroke thereof, a gun air supply control valve mounted upon said carriage and comprising a housing having an interior bore accommodating a valve spool, said valve housing bore being at one end in pressure communication with the fluid pressure causing reciprocation of said carriage, a compression spring acting against said valve spool biasing it toward said one end of said housing bore, apertures extending transversely through said spool, a gun air supply port extending through a wall portion of said valve spool, a gun air outlet port extending through another wall portion of said housing and in communication with conduit means delivering supply air therefrom to the spray guns, the apertures through said valve spool being so positioned and arranged that the gun air supply and air delivery ports of said housing are intercommunicated upon displacement of said valve spool against said spring incidental to reciprocation of said carriage.

4. In a bufi'ing or polishing machine, a compound spray gun mover for mounting and moving a spray gun relative to the working rolls of said machine, said gun mover comprising a carriage mounted upon said machine for reciprocation in directions longitudinally of the machine rolls, means mounting spray guns upon said carriage, a pneumatic piston-cylinder device actuating said carriage to reciprocate relative to said machine, a carriage motion control valve operable to deliver compressed air alternatively to opposite ends of said cylinder, means responsive to arrival of said carriage at the limits of the selected travel stroke thereof to actuate said valve means to cause delivery of compressed air alternately to opposite ends of the cylinder, said carriage being connected to the piston rod of said piston-cylinder device, said piston rod being hollow and open-ended'interiorly of said cylinder, a gun air supply control valve mounted upon said carriage and comprising a housing having an interior bore accommodating a valve spool, said valve housing bore being at one end in pressure communication with the hollow interior of said piston rod, a compression spring acting against said valve spool biasing it toward said one end of said housing bore, longitudinally spaced apertures extending transversely through said spool, a gun air supply port extending through a Wall portion of said valve housing, a gun air outlet port extending through another wall portion of said housing and in communication with conduit means delivering supply air therefrom to the spray guns, the apertures through said valve spool being so positioned and arranged that the gun air supply and air delivery ports of said housing are intercommunicated upon displacement of said valve spool against said spring incidental to passage of compressed air through said hollow rod, and a vent port through another wall portion of said housing and arranged to vent all pressures interiorly of said housing when said spool is biased by said spring against said one end of said housing.

5. In a buffing or polishing machine, a compound spray gun mover for reciprocating a spray gun lengthwise of the machine rolls, said gun mover comprising a carriage mounted upon said machine for sliding reciprocation thereon, means for mounting a spray gun upon said carriage, a fluid-pressure cylinder device actuating said carriage to reciprocate, a carriage motion control valve actuatable to deliver pressured fluid alternatively to said opposite ends of said cylinder, means responsive to arrival of said carriage at the limits of the selected travel stroke thereof to actuate said valve, said carriage being connected to the piston of said piston-cylinder unit, said piston being hollow and open-ended into one end of said cylinder, a gun air supply control valve mounted upon said carriage and comprising a housing having an interior bore accommodating a valve spool, said valve housing bore being at one end in pressure communication with the hollow interior of said piston, a compression spring acting against said valve spool biasing it toward said one end of said housing bore, longitudinally spaced apertures extending transversely through said spool, a gun air supply port extending through a wall portion of said valve housing, a gun air outlet port extending through another wall portion of said housing and in communication with conduit means delivering supply air therefrom to the spray gun, the apertures through said valve spool being so positioned and arranged that the gun air supply and air delivery ports of said housing are intercommunicated upon displacement of said valve spool against said spring incidental to transmission of said valve spool against said spring incidental to transmission of fluid pressure through said hollow rod.

6. In a machine having a bufiing' or polishing roll, a

compound spray gun mover for reciprocating a spray gun lengthwise of said roll, said gun mover comprising a carriage mounted upon said machine for sliding reciprocation thereon, means for mounting a spray gun upon said carriage, a pneumatic piston-cylinder device actuating said carriage to reciprocate, a carriage motion control valve actuatable to deliver compressed air alternatively to said opposite ends of said cylinder, means responsive to arrival of said carriage at the limits of the selected travel stroke thereof to actuate said valve, said carriage being connected to the piston of said piston-cylinder unit, said piston being hollow and open-ended into one end of said cylinder, a gun air supply control valve mounted upon said carriage and comprising a housing i 7 having an interior bore accommodating a valve spool, said valve housing bore being at one end in pressure Communication withthehollow interior of said piston, a compression spring acting against said valve spool biasing it toward said one end of said housing bore, longitudinally spaced apertures extending transversely through said spool, a gun air supply port-extending through a wall portion of said valve housing, a gun air outlet port extendingthrough another wall portion of saidhousing and in comniun'icat ion Withconduit means delivering supsaid valvespool being so positioned and arranged that the gun air supply and air delivery ports of-saidhousing 10 ply air therefrom to the spray gun, the apertures through areinte'rcornmunicated up o displacement of said valve spool against said springg-incidentalto passage of corn- P i T th qv k s l-- Qd 5':@ i t b1 thr t lc. Y'QlY m l a in i I t v la r b o th -QW sure withiri said hollow piston: rodsand operation of sai d spray guns; I

l [References Cited in the file of this patent UNITED :STATES PATENTS 2,555,237 M ac Pherson May 29, 1951 e ve t port -of ,said carriage potion

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