US500749A - Steam-engine - Google Patents

Description

(NO Model.) 2 Sheets-Sheet 1.

R. D. WERDEN.

STEAM ENGINE.

No. 500,749. Patented July4, 1893.

NITED STATES PATENT FFICE.

RODOLPIIUS DAVIS \VERDEN, OF CINCINNATI, OHIO.

STEAM-ENGINE.

SPECIFICATION forming part of Letters Patent No. 500,749, dated July 4, 1893.

Application filed December 9, 1892. Se1ial No. 454,673. (No model.)

T0 wZZ whom i mcoy concern:

Be it known that I, RODOLPHUS DAVIS VVERDEN, a subject of the Queen of Great Britain, residing at Cincinnati,in the county of Hamilton and State of Ohio, have invented certain new and useful Improvements in Steam-Engines, of which the following is a full, clear, and exact description, reference being had to the accompanyng drawings, forming part of this specification.

My invention relates to all classes of stationary engines but is more particularly designed for those engines requiring a uniformity of speed under varying loads, and it has for its object the improved performance of suoh eugines whereby there are secured an economy of steam, uniformity of speed under variable loads, the prevention of undue valve leakage, the prevention of terminal pressures below any back pressure, and the prevention of undue cylinder condensation.

The novelty of my invention will be hereinafter set forth and specifically pointed out in the claims.

In the accompanying drawingsz-Figure 1, Sheet 1, is a sectional plan view of an engine embodying my invention. Fig. 2, Sheet 2, is an elevation of the governor, fly, and belt wheels taken on the dotted line 00 x of Fig. 1. Fig. 3, Sheet 2, is a plan view of Fig. 2 looking at the sarne in the direction of the arrow at the right, and with portions broken away to show the shifting meohanisrn for the valve controlling the admission of steam to the cylinder.

The sanue letters of referenceare used to indicate identical parts in all the figures.

The construction of the engine, exoept in the particulars to be pointed out, may be that usually employed or it may be of any desired construction,and it is only necessary in describing it to say that, A is the cylinder, B the steam chest, with the usual ports and with slide valve (1 and cut off slide b, 0 the piston in the cylinder,l) its rod, E the pitman, F the crank or crank disk, G the driving shaft, and

H I the ecoentric rode for the slide valve and cut oi, respectively. The fly wheel J is fast on the shaft G and has secured upon it in the usual or any suitable manner the yielding driving wheel K with interposed hearing rolleis 0 and connecting springs d,Fig. 2. Loose on the shaft G beside the wheel J is the usual or any suitable governor wheel L with Weight e, pivoted weighted arm f and spring g. A lever h Fig. 2, adjustably pivoted as at 1 to the fly wheel arm has its inner end pivoted to the governor wheel as atj and its enter end pivotally connected, in this instance by a pivoted link 7 to the wheel K. Likewise loose upon the shaft G by the side of the governor wheel is the ecoentric M for the cut off 1od I While the eccentric N for the slide valve rod H is fast on the shaft G. The eccentric M has a hub with a projecting lug Zwhich is adjustably and pivotally connected by a link m to the outer end of the weight armf.

Feathered upon the shaft G is a collar O, Figs. 1 ahd 3 having a circumferential groove in which is confined the fork of a lever P pivoted as at 11 and suitably connected at its rear to the adjustable stem of the steam controlling valve Q, in this nstance represented as an ordinary puppet valve, for admitting steam. to the steam chest. Suitably journaled in the fly wheel, in this instance on its hub and through its ri1n, is a radial rod p having its outer end bent to form a crank q engaged loy pins 0 on the inner side of the wheel K, see Figs. 2 and 3, and having its inner end bent to form a crank s which is pivotally connected by a link t to the collar 0.

The adjustment of the parts is such that when steam is shut off and the engine at rest the springs d exerting their force on the rod p throw the collar outward so as to nearly but not entirely close the valve q. The eccentrics M N are propcrly adj usted to each other, and the weight 6 is drawn in. The wheel K is beltecl to the load and we will suppose the engine to be started by the admission of steam through the slightly open valve Q. The first eiect wouldbe the compression of the springs a the wheel K standing still for an instant, and the drawing in of the collar 0 thereby opening valve Q to an extent proportionate to the load. At the same time, and by the same relative movements of the wheels J and K the governor wheel is turned forward by lever h thereby shifting, through medium of link m, the eccentric M to such a positon that the cut off b does not interfere with the full action of the slide valve. As the wheel K begins to turn and the inertia of the load is overeome the whee1 K is shifted forward by the aetion of the spring d thereby e1osing down the va1ve Q t0 admit less steam and bring the eceentric M into sueh position chat the cut off comes into play t0 eut off at any desired portion of the stroke S0 that the steam acts on the piston by its expansion alone bui: nevel to such a degree that it gets below beek pressure at the termination of the stroke. Should the speed inerease beyond the norma1 degree desired the aotion of the weight e wil1 s0 further shift the eecentrie as to cause the eut 0fl" l0 act quicker and thereby prevent the acceleration of the speed. The moment however an extra load eomes en, the wheei K again shifts relativeiy t0 J by being retarded and the valve Q and eceentrie M are again acted en toedmit proportionate pressure, which is again gradually cut off as the conditions and adjustments again become normal, and to cause the cut off t0 act; quieker. In ths way and by the use of these eompound governors the aetion of the engine is entirely automatic in controlling the proper minimum amount of steam and the speed, no matter how the 1oad may be varied. In this way a1so the eut 0 is made to aet in opposition t0 its former plan of use, for With my eonstrnetion the greater the load the quicker the enta off is made.

By way of illustration of the action of the cut off with variable loads I have shown an indicator diagram in Fig. 1, where it is assnmed that the initial pressure at the beginning of the stroke is sixtypounds, and the 0111 0ff is made at quanter stroke. Under these conditions the pressure at quarter stroke when euta 0ff is made, would be sixty pounds; at half stroke it would be thirty pounds; atthree quarters stroke it would be twenty-two and ene-half p'ounds, and at the termination of the stroke fifteen pounds or atmospherie pressure, or very slightly above this. N0w supposing the load to be decreased S0 as to close vave Q to admit thirty pounds the eeeentric M would then be adjusted by lever h 110 cut off at haif stroke and pressure there would still be thirty pounds, and at three qnarter srroke t would be twenty-tvvo and ene-half pounds, and at the end of the stroke fifteen ponnds, er slightly above as before.

IVhi1e the greatest benefit of my in vention comes from eontrolling the cut off both by the load and the speed, in conn ection with ZL th rott1ing governor, yet a large part of the benefio of my invention e0u1d be obtained by disconnecting the wheel K from the eceentrc M, through the medium of the governor wheel L,

end making the 1atter fast to the shaft G 0r vvheel J. In sueh case the eeeentric M wonld only be adj usted by the speed, as Will be readily understood and while I have shown suitable meehansms fox connecting the load vvhee1 and shaft wheel with the thr ottling gevernor and with the governor wheel and eeeentrio for the cnt ofi I do not wish my invention to be limited to these construetions as they might be varied in a varieiay of ways.

IIaving thus fully descrbed my invention, I claim 1. In en engine, the combination with a1oad governor mechanism and throttle valve actuated thereby, of a variable cut off controlled by the speed.

2. In en engine, a variable cut off, a speed governor mechanism, a10ad wheel and shafb whee1 with interposed throttle valve mechanism aetuated by their relative shifting, a connection between the 10ad whee1 and variable ent off, and a een neeton between the speed governor and. variable cut off, vvhereby the engine is eensed to run with uniform speed under varying loads substantially as deseribed.

3. In en engine, a variable cut off, a speed governor mechanism, a load wheel and shaft whee1 with interposed throttle valve mechanism aetuated by their relative shifting, an eecentrie for said ent 0ff loose on the shaft, a conneetion between the 10ad wheel and eccentric, and a connection between the speed governor and eceentrie, substantially as descrbed.

4:. In en engine,the eombination of a s1ide valve, a eut 0ff valve, a throttling valve for the steam chest, a load whee1 and shaft wheel With interposed meehanism for aetuating the throttling valve eontrolled by their relative shifting, a speed governor an eccentrie 100se on the shaft for the cut; off va1ve, a connection between the leed wheel and snid eccentrio, and a eonnection between the speed gevernor and said eeeentric, substantiailyas deserbed.

R. DAVIS WERDEN. Witnesses:

J. THOIVISON CROSS, BERNARD J. HAUSF'ELD.

IOO

Images