US25005A - Improvement in governor-valves - Google Patents

Description

UNITED STATES PATENT OFFICE.

BENAIAH FITTS, OF VORCESTER, MASSACHUSETTS.

IMPROVEMENT IN GOVERNOR-VALVES.

Specification forming part of Letters Patent No. 25,005, dated August 9, 1859.

To all whom t may concern:

Be it known that. I, BENAIAH FITTS, of the city and county of Vorcester, and State of Massachusetts, have invented a new and useful Improvement in Governor-Valves; and I do hereby declare that the following is a full, clear, and exact description of the construction and operation of the same, reference beeing had to the annexed drawings, making a part of this specification, in which-- Figure l is a top view of the outside of valve with the cap removed, so as to show the top of the valve itself in an open position.- Fig. 2 is a section through r s, Fig. 1. Fig. 3 is a section through w Fig. 2. Fig. 4 is a section through y z, Figs. 'land 3.

Similar letters refer to the same parts in all.

The nature of my invention consists in a peculiar manner of mounting the valve, so as to dispense with the use of stufling-boxes, and whereby the resisting action of pressure of steam and of friction upon the valve is greatly diminished. This valve consists of a globularformed chamber, which is divided by a valveseat, valve, and partitions into compartments so constructed as to balance or graduate the pressure upon the valve, and being firmly fastened in its position'in a peculiar manner it will shut perfectly tight, when desired, un-

der varied pressures and temperatures, `at the same time being` moved with the least possible amount of friction or resistance.

To point out the different parts and show how it is constructed, A A is the chamber or globe in which the valve and valveseat are situated and through which the steam passes.

B is a cap to close the aperture in the chamber through which the valve passes when it is inserted.

C is the valve, which should be made on an angle of about ninety degrees, for reasons hereinafter given.

D D is the valve-seat.

E E is the ingress or induction pipes or passages.

F F is the egress or eduction passages.

G is a chamber through which the steam passes, but is cut off from both ingress and egress pipes when the valve is closed.

H H is a partition between the ingress and egress pipes, and is connected to the valveseat.

I is partition between chamber G and the;

pipes or passages E and F.

K is the valve-stem, to which the level' or arm is attached to operate the valve.

L is the lever.

M M is a quill screwed through the valveseat around the stem of valve, and forms a part of the valve-seat, and is so fitted that it may be raised or screwed in so that nearly all of the pressure upon the valve will rest upon a very small part of its surface near to the stem, and thereby relieve it from friction.

N is a solid shoulder upon the stem of the Valve and made adjustable by the nut S, and is ground or fitted steam-tight against the end of the quill M.

O O are induction port-holes through the valve and its seat, through which the steam passes from passage F. to chamber G.

P P are the eduction port-holes, through which the steam passes from chamber G to eduction-passages F, and are usually made a little narrower than port-holes O O, but are of the same length.

The operation is as follows: The valve being thrown open, as shown in Fig. l, to allow the steam to pass through until a sufficient pressure has been gained in the eduction-pipe and steamchest to drive the engine at the required speed, the valve is then partially closed by the governor, so as to maintain that pressure only. In doing so the resistance of the steam rests equally against each side of the valve, or the pressure may be graded, throwing the greateramount upon the top side by making the eduction-ports P P a little smaller than ports O O, as shown inthe drawings. For example, if there is one hundred pounds pressure of steam to the square inch in the boiler and induction Lpipe and it rcquires but ten pounds to the inch to work the engine, the pressure in chamber G will be (if the induction and ed uction ports are of equal size) a medium between one hundred pounds and ten pounds, orlifty-iive pounds. Thevalve having turned nearly into the position shown in Fig. 3, so as to cover one inch of each porthole, the pressure on the under side through port-holes O O will be one hundred pounds each,or one hundred multiplied by two equals two hundred pounds. Through ports P P it will be ten pounds each, or ten multiplied by tWo equals twenty pounds, amounting in all to two hundred and twenty pounds. On the top side of the valve it will be fifty-tive pounds each, equaling fifty-tive multiplied by four, equaling tWo hundred and twenty pounds. Thus the pressure will balance, making a balanced valve. To throwa small amount of pressure on the top side to keep the valve down upon its seat under ordinary circumstances, the port-holes P P are made a little smaller than O O, as shown in the drawings, which willcause the pressure in chamber Gr to be a little more, than the mean pressure, or the proportion between the port-holes P P and O O may be such as to grade the pressure, giving any amount which may be desired upon either side ot' the valve to cause it to work well in particular place or position, thus making a graduated Valve.

As the pressure changes, as above stat-ed, from one hundred pounds in the inductionpipe to ten pounds in the eduction-pipe, the temperature also changes nearly 100", which will canse certain parts of the valve and valve- ,Mseat to be much more expanded than others,

they being the dividing-line; but as metal expands equally in all direct-ions if the valve is made on an angle of ninety degrees, as shown above, the joint will not be affected by such a change of temperature, the valve expanding in circumference in the same proportion as in length through its axis, thus securing a tight j oint under varied pressures and temperatures. Vith the valve made upon this an glo it may be firmly held down tothe seat by the shoulder M against any reaction which there may be in the pipe from various causes such as reversing the engine, opening or closing other valves in the same pipe, dac., which is not the case when the valve is made on any other angle. Resting the valve on its seat, as shown at M, together with the shoulders N, as shown and described, secures a tight joint around' the stem, thus dispensing with the necessity of a stuiingbox and also the friction caused by the stufiing, which is in some instances enough to resist nearly all the force of the governor. It also dispenses with setscrews or centers for the valve to turn on.

Having thus fully described the construction and operation of the separate parts of my invention, it will be seen that when combined or taken together it constitutes a most simple and efficient valve for governors and like purposes.

Having thus described my improvement, what I claim as new, and desire to secure by Letters Patent, is-

The manner of mounting the valve, substantially as herein described-that is to say, resting or supporting the valve, as shown at M, and retaining it into its sea-t, as shown at N, for the purposes s et forth.

BENAlAH FI'FTS. W'itnesses:

E. C. TAINTER, W. H. MANAHAN.

Images