US687070A - Valve-gearing. - Google Patents

Description

No. 687,070. Patented Nov. |9,|9o|.

A. H. SCHMIDT.

VALVE BEARING.

(Applica tion'filed June 14, 1901.)

' (No Model.)

YHE nonms vsrzns co. PNOTO 211x01, WASHINGTON, D c.

UNITED STATES PATENT OFFICE.

AUGUST HERMANN SCHMIDT, OF HAMBURG, GERMANY.

VALVE-GEARING,

SPECIFICATION forming part of Letters Patent No. 687,070, dated November 19, 1901.

Application filed June 14, 1901.

To all whom it may concern:

Be it known that I, AUGUST HERMANN SCHMIDT, a subject of the German Emperor, and a resident of Hamburg, in the German Empire, have invented certain new and usef ul Improvements in Valve-Gearings,of which the following is a specification.

The present invention relates to improvements in distributing valve-gearing for quickrunning pumps, and has for its object to produce such a valve-gearing'which is exceedingly simple in construction and thoroughly efficient and reliable in operation.

The invention consists in several features of construction, as hereinafter described and claimed with reference to the accompanying drawing, in which I have shown a longitudinal sectional elevation of my improved distributing valve-gearing in connection with a pump.

The characteristic feature of my new valvegearing consists in the arrangement of the compressing-springs n n and "mfm above and below the suction and forcing ordelivery valves 3 and g, respectively. These springs are alternately compressed and released by the rods h and 712, the latter being actuated both in the same and in the opposite direction of the motion of the pump-piston (plunger) by means of the eccentrics t and 16 which are fixed onto the shaft 6, whereas the crank c of the shaft e, running in the bearings Z and Z actuates the pump-piston by means of the connecting-rod d and the piston-rod h, working in the gland a.

According to the foregoing the action and operation ofmy valve-gearing are as follows: In the drawing I have shown the pump-plunger c at the limit of its forcing stroke, the crank 0, connected with the plunger-rod it through connecting-rod (1, being in a position to reverse the stroke of the plunger, the valverod h under the action of its eccentric i having completed'its downstroke and closed the delivery-valve g by the action of the collar 0 on the spring m whereby the latter is compressed and the Valve held firmly to itsseat. This downstroke of the valve-rod if, and with it its collar 0 ,.relieves the spring 01 of pressure and allows it to expand, said spring moving with the rod out'of contact with the hub Serial No. 64,576. (No model.)

of the valve g, in which said rod has free motion. At the same time the valve-rod h has made its upstroke under the action of its eccentric t', the collar 10 on said rod having moved out of contact with spring m, while collar p has moved the spring n into contact with the hub of the suction-valve s and' brought it under sufficient tcnsion'to unseat the valve, which takes place as soon as the stroke of the pump-plunger is reversed-that is to say, the moment the pump-plunger c begins its suction-stroke-so that the body of waterldrawn in through suction-pipe c flows freely or practically without resistance into the pumpchamber. As the pump-plungerc completes its suction-stroke and is about to begin its forcing. stroke the valve-rod 7&2 will also have completed its upstroke,collar 0 moving spring a into contact with the hub of delivery-valve g and placing said spring under sufficient tension to unseat said valve the moment the plungericbegins its upstroke, the water, passing freely'or with practically no resistance from the pump-chamber to the de -livery branch w; At the same time the valverod h has completed its downstroke, its collar {p impinging upon spring m during this movement, compressingthe Same,and thereby moving the suction-valve s and holding it firmly to its seat, while spring n is relieved of tension by the movement of the collar 1) away from the hub of valve 8. v

Aswill be readily understood, the valves 9 and S are gravity-valves and are held up to and moved off theirseats bya tension device on either side of the valve, the tension of k which is controlled by the valve-rods, so that said tension device is brought gradually under tension or'relieved of tension practically i'nproportion to the reduction of pressure on the valve. Thus, for instance, the springs 1 m n, acting on valves g and s, gradually move the same to and from their seats; this being the case in respect of the springs 71? and m, except that the valve 9 is unseated and valve sis seated and whereby the hammering of the valves is practically avoided,

To secure reliable and steady motion of quick-running pumps, the following wellknown condition must be fulfilled: The head or forcing valve must have been closed at the of the forcing period or must be closed without any jars in due time to prevent the water in the pump-cylinder from flowing back into the suction-pipe. At the commencement of the forcing period the forcing-valve must be relieved or balanced as much as possible,

so that the water can flow from the cylinder of the pump without any hindrance at the commencement of the stroke. The stroke of the valves must always correspond to the speed of the plunger-piston'as nearly as possible in order to obviate acceleration or retardation in the flow of the Water, as such intermittent flow causes irregular action and jarsof the pump. During the reversal from suction to forcing no change in the direction of the flow of water ought to take place.

The above conditions are entirely or practically entirely fulfilled by my improved valve-gearing, as will be evident from the following facts: As soon as the plunger-piston has passed the point of its greatest velocity the spring m of the forcing-valve g is gradually compressed by the influence of the corresponding eccentric t the result being that the compressed spring m closes the said valve immediately the stroke is reversed, and as at the same time the lower spring n is compressed by the action of the ascending motion of the eccentric t the sucking-valve becomes relieved, and consequently opens at once automatically on the diminutionof pressure in the pump cylinder. At the commencement of the'forcin g period the suckingvalve is closed so rapidly and without any jars that a backflowing of the water from the pump-cylinder into the suction-pipe cannot take place. Simultaneously the forcingvalve g is relieved so far as to be capable to be raised by the aid of the compressed spring 71 thus permitting the water to pass fromthe cylinder through the outlet w into the foreing-pipe at the beginning of the stroke. The diminution of the valve motion before its entire closing is brought aboutby the graduallyincreasing compression of the spring,whereas the increase of the valve motion at the commencement of the stroke of the plunger-piston is caused by the increasing body or bulk of the conveyed water. The reversal of the direction of the flow of water is obviated as far as possible by the descending of the plunger-piston' during the sucking period.

Of course I can apply the herein-described means not only to single-acting but also to double-acting pumps.

It is also understood that I can employ expansion-springs in the place of compressionsprings to cause the desired motion of the valves, said expansion-springs being expanded according to the desired degree of the valve motion.

Having fully described my invention, what I claim, and desire to secure by Letters Patcut, is--- 1. The combination with the pump cha ns her and plunger, the suction and forcing ports of said chamber, gravityvalves controlling said ports, a crank-shaft connected with the plunger and eccentrics on said shaft; of a tension device on either side of each of and arranged to act directly on said valves and means controlled by the eccentrics on the crank-shaft to cause one or the other of said tension devices to act upon its valx'e to seat or unseat the same according as the plunger makes its suction or forcing stroke, for the purposes set forth.

2. The combination with the pump chamber and plunger, the suction an d forcing ports of said chamber, gravity-valves controlling said ports, a crank-shaft connected with the plunger and eccentrics on said shaft; of valverods on which the valves are loosely mounted, said rods connected with the eccentrics and having an abutment on either side of their respective valves, and springs loosely mounted on either side of the valves between them and the abutments on their respective rods, for the purpose set forth.

3. The combination with the pump chamber and plunger, the suction and forcing ports of said chamber, gravity-valves controlling said ports, a crank-shaft connected with the plunger and eccentrics on said shaft; of valverods on. which the valves are loosely mounted,

said rods connected with the eccentrics and having an abutment on either side of their respective valves, and springs loosely mounted on either side of the valves between them and the abutments on their respective rods, said abutments so arranged that the one on one side of a valve will, during the stroke of the rod, move out of contact with the spring on that side, while the abutment on the opposite side of the valve will on the reverse stroke of the rod move its spring out of contact with the valve, substantially as and for the purpose set forth.

AUGUST HERMANN SCHMIDT.

Witnesses:

MAX KAEMPFF, ERNEST H. L. lVIUMMENHOFF.

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