US2679208A - Proportioning device - Google Patents

Description

May 25, 1954 M. R. EUVERARD 2,679,208

PRoPoRTIoNING DEVICE Filed June 27, 1951 2 sheets-sheet 2 IN VEN TOR. Maj/Hara E, ZZA/@mrd Patented May 25, 1954 PROPORTIONING DEVICE Maynard R. Euverard, Short Hills, N. J., assignor to Intcrchemical Corporation, New York, N.'Y.`, a corporation of Ohio Application June 27, 1951, Serial No. 233,809

3 Claims.

This invention relates to a fluid proportioning apparatus of a type which is specically useful for controlling the ow of paint and catalyst solution to a spray gun.

Mixing relatively large `volumes of paint with small amounts of catalyst solution in a fixed ratio just before atomization at a spray gun nozzle is important in the coating industry. A commingling of the paint and the catalyst immecliately prior to the application is required because, if added too early, the catalyst causes partial or complete solidiiication or the coating material so that it cannot be fed through a spray gun. Until now it was not possible to take full advantage of catalysts in spray coating, due to the lack of suitable proportioning means. The herein disclosed device permits the use of quick acting catalysts in efficient amounts, resulting in a material shortening of the curing time and in a reduction of the temperatures required in curing spray coatings.

The principal object of the present invention is, therefore, to accurately proportion two or more liquids the volume of one of which is large with respect to the combined volumes of the others and to control the flow of the small volume iiow by the flow of the large volume.

A more specific object of the invention is to provide a device designed for proportioning and mixing coating materials and catalysts close to .ie spray head of a spray gun, immediately before applying the coating.

A still more specific object of the invention is that the hydraulic pressure of the large volume material supply line to the spraying device furnishes the power source for operating the proportioning means, so that no external source of power need be started and stopped when operating the device.

Further objects and advantages will appear from the description and the accompanying drawings.

In the drawings,

Fig. 1 is a plan view of the assembled device.4

Fig. 2 is a sectional view taken on the line 2 2 in Fig. 1.

Fig. 3 is a sectional View taken on the line 3 3 in Fig. 2.

Fig. 4 is a sectional View taken on the line 5 4 in Fig. 1. Y

Fig. 5 is a rear elevation of the device. Eig. 6 is a sectional View taken on the line 6 6 in Fig. 4.

device is shown fastened to a base plate li which lconnects to the main iluid outlet 2l.

rests on the bars I2. .As illustrated, one way of mounting the device is by means of two columns i 3 provided with threaded Shanks i4 that are set into the base and are fastened thereto by means of the nuts I5. The threaded shafts l5 and Il extending upward of the columns are dimensioned so as to t into and to partly plug the borings 22 and 23 drilled vertically through the proportioner block 2|. rl'he open portions of these borings communicate with the conduits 2&3 and 25 drilled horizontally through the proportioner block. The first of the said conduits connects to the main fluid inlet 26 and the second Inserted into the conduits is the valve port 28 fitted with the rotary valve 29 and the valve retainer 3G. The valve is held in position by bearings 3l and 32 which, at the same time, serve as closures for the valve port. The valve is arranged to be turned by meansof the valve stem 33 and the valve arm 34 having a valve arm pin 35 as shown.

The boring ll drilled through the proportioner block constitutes the motor cylinder. As shown, this Vcylinder'is in communication with the borings 22 and 23 and, by Way of these borings, with the conduits 24 and 25 and the valve port 28. Inserted into the cylinder is the main drive rod 42, held in alignment by the cylinder end caps 43 provided with gaskets M. Fastened to the said drive rod and suitably iitted to reciprocate within the motor cylinder is the piston 45.

Attached to the main drive rod are two cross bars which, as indicated in Fig. 1, hold between themselves the valve spring tripping bar 5ft, a follower guide bar 'i3 and the two plungers ld. However, I prefer to replacethe cross `bars by end plates 5|, preferably having the shape of circular disks with opposite segments out away. The end plates are provided with sleeves 52 which fit over the ends of the drive rod and are iastened thereto by means of the locking screws 53. Arranged between these end plates to be moved reciprocally by them but, preferably, not xedly attached to them, is the said valve spring tripping sbar, the said follower guide bar and the said two plungers. The endsof the follower guide bar and the drive end of each plunger are set jointly in blocks l5. Oneway of avoiding ashiiit in the position of the end plates 5| about the axis of the main drive rod while the device is in operation isto lock `the 'end plates to the valve spring tripping bar r54. For this purpose, the bolt 96 secured by the wing nut 95 is inserted into a slot 98 suitably provided at one of the end plates. This bolt and a stop pin 91 are spaced so as to confine one end of the valve spring tripping bar therebetween. By moving the bolt 96 out of the way of the valve spring tripping bar, the end plates can be turned into a position whereby they clear the Valve spring tripping bar and the blocks retaining the ends of the follower drive bar and of the plungers. The motor and the pump follower can then be operated independently of each other, which is important for priming the system and for cleaning. ln Order to minimize lateral stresses on the follower guide bar and the plungers while they are reciprocated by the end plates, sockets are provided to receive the small balls 15, properly spaced in the blocks 15.

The valve spring tripping bar 54 is held by two brackets 55 and is retained in position by the caps S screwed onto the brackets. Fitted to the said bar is the bolt 51 which can be adjusted in length by the lock nut 58. Held between the valve bearing 32 and a retaining nut 3S is the valve plate 31 having a pin 38 and a groove The groove has a circular curvature with the valve stem 33 as the center and is tted to receive the pin 35 of the valve arm 3Q.

A spring 5| is fastened between the pin 3d of the valve plate and the bolt 51 of the valve spring tripping bar. The stops 32 serve to restrict the movement of the valve arm 311 and the valve plate 31 induced by the spring.

Suitably attached to the proportioner block is the pump follower housing 1|, carrying two brackets 12 which keep the follower guide bar 13 reciprocally in position. There are two cylin" ders 11 drilled into the pump follower housing which can be either arranged in line or, as shown, be vertically set off against each other in order to furnish a more compact device. lnserted into the pump follower cylinders are the plungers 16S which have a diameter appreciably smaller than the cylinder diameter. The displacement volume of the plungers determines the amount of secondary fluid material to be proportioned. The plungers enter the respective cylinders through sleeves 18 and are centered in position by means of the retaining washers l, inserted in suitably provided spaces. As stated previously, the drive ends of the plungers are set into blocks 15, jointly with the ends of the follower guide bar 13.

Drilled vertically into the pump follower housing from below are the conduits 8| and S2. which connect the cylinders 11 with the secondary fluid inlet valve assembly 83, while the conduits 84 and S5 connecting the cylinders 11 with the seconda-ry fluid outlet valve assembly 86 are drilled vertically from above into the pump follower housing.

These secondary uid inlet and outlet valve assemblies are fastened to the pump follower housing 1l by means of bolts 81, illustrated in connection with the secondary fluid outlet valve assembly 85. The assemblies consist of blocks having borings communicating with the conduits iii, 82 and 84, 85, respectively, which connect the secondary fluid inlet 88 to the pump follower cylinders 11 and the latter to the secondary fluid outlet 8s. Appropriately inserted in the borings are the check valves 90.

With the rotary valve 29 and the piston i5 in a position as shown, if a liquid under pressure enters through the main fluid inlet 26, a direct passage of the liquid to the main fluid outlet 21 is prevented by the rotary valve. The liquid is forced through the boring 22 into the space to the left of piston 45 and, because of its pressure, forces the piston to move to the right. The end plate 5| fastened to the main drive rod 2 forces the valve spring operating bar 54 to move also 'to the right. The bolt 51, which is set into the said bar and to which one end of the spring l is attached, exerts an increasing tension upon the said spring. After, induced by the movement of the bar 54 and the bolt 51, the spring Si has passed dead center, it quickly accelerates the valve plate 31 through 45, providing the necessary lever arm and imparting sufcient velocity to the valve plate to turn the valve 29, practically instantaneously, through the extent of its rota tion.

As a result of this 90 change in the position of the valve the incoming liquid is now forced to travel from the main fluid inlet 26 'through the right end of conduit 25, into the boring 23 and 'thence into the right hand space of cylinder 51, forcing the piston 45 to reverse its direction of travel. ln the meantime, while the piston was moving to the right, liquid accumulated in front of the piston was forced through the main iluid outlet 21.

Simultaneously with the valve spring operating bar 54 being moved to the right by pressure exerted by the left end plate 5l, the follower guide bar 13 and the left plunger 1d of the pump follower are also being forced to the right. While secondary fluid accumulated in front of the left hand plunger in the lower cylinder 11 is being forced through the secondary fluid outlet the volume of the right hand plunger le receding from the upper cylinder 11 is replaced in the said cylinder by liquid drawn from the secondary fluid inlet 88.

The rate at which the secondary fluid is proportioned to the main iiuid is determined by the ratio 1/4 DzvrS: 1/4 dzvrs; D being the diameter and S being the stroke of the piston 45, and d being the diameter and s being the stroke of the plungers 545. If, for example, D, S and s are kept conu etant and d is varied by providing exchangeable sets of plungers 14 of various diameters, together with appropriate fittings 18 and 19, the device is adaptable for various proportioning requirements, as illustrated by the following table.

parts by parts by volume of volume of diameter of l main secondary plungcrs, fluid fluid inch material material 10 1 0 306 l 0. 250 1 0.216 25 l O. 191 l 0.178 1 0.153 l 0.137

I claim:

1. A proportioning device comprising a, pressure flow operated motor consisting of a casing having a fluid inlet and a uid outlet, a valve port, two conduits suitably spaced to traverse the Valve port, the rst of the said conduits connecting to the fluid inlet and the second connecting to the fluid outlet, a cylinder arranged parallel to the said conduits and suitably attached to the said casing, ducts connecting the said conduits to opposite extremities of the cylinder, a rotary valve arranged in the said valve port to permit the passage of incoming uid through the first of the said ducts and the passage of outgoing uid through the second of the said ducts when turned into one position, and to permit the passage of outgoing uid through the iirst of the said ducts and the passage of incoming uid through the second of the said ducts when turned into another position, closures for the Valve port, a valve stem extending through one of the closures and having a valve arm with a valve arm pin, a valve plate which is rotatably held between the said closure and the said valve arm and has a valve plate pin and a curved valve plategroove fitting the said valve arm pin over an arc of about 45, stops arranged to restrict the movement of the valve arm and the valve plate, end caps for the cylinder, a piston reciprocally fitting into the cylinder, a piston rod extending through the cylinder end caps, cross bars fastened to the tips of the piston rod, a valve spring tripping bar reciprocally tted between the said cross bars and attached thereto parallel to the piston rod, a spring, held between the said tripping bar and the said Valve plate pin, which, upon liquid under pressure entering the said cylinder at one of the extremities and forcing the said piston and the said trippingl bar in the direction of the other extremity, after passing dead center quickly accelerates the said valve plate into an arcuate motion of suicient velocity to turn the said valve arm and the said rotaryvalveintoaposition which causes entry of liquid under pressure at the other extremity of the said cylinder, and a pump follower consisting of a housing in juxtapositionwith the motor casing, an inlet valve assembly and an outlet valve assembly, two borings drilled from opposite sides into the said. housing, separate conduits leading from the said borings to the said inlet Valve assembly and to the said outlet valve assembly, lids for the said borings, and attached to each of the said cross bars a plunger having a diameter smaller than the diameter of the borings and extending through one of the said lids into one of the said borings.

2. A proportioning device according to claim 1, wherein a follower guide bar is reciprocally arranged parallel to the said piston rod and the said plungers, each end of the said follower guide bar is coupled with the driving end of one of the said plunger-s, the cross bars fastened to the tips oi the said piston rod are replaced by circular disks having opposite segments cut away, and means are provided permitting to secure the dislrs in a position wherein they impart synchronous movements to the reciprocating elements of the motor and the pump follower and to turn the disks into a position wherein the motor and the pump follower can be operated independently of each other.

3. A proportioning device according to claim 2, wherein the borings drilled from opposite sides into the said pump follower housing are set off plane-parallel against each other.

References Cited in the file 0f this patent UNITED STATES PATENTS Number Name Date 335,855 Toole Feb. 9, 1886 354,613 Toense Dec. 21, 1886 2,124,797 Rust et al July 26, 1938

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