US253938A - Automatic cut-off-valve gear - Google Patents

Description

(NoModeL) J. W. MORGAN. AUTOMATIC GUT-OFF VALVE GEAR. N0.253,938. Patented'Feb.;21.1882.

v i I "I Mira UN TED STATES JOHN W. MORGAN, OF ST. LOUIS, MISSOURI.

-AUTOM ATIC CUT-QFF-VALVE GEAR.

SPECIFICATION forming part of Letters Patent No. 253,938, dated February 21, 1882.

Application filed January 10, 1881. (No model.) I

To all whom it may concern:

Be it known that I, JOHN W. MORGAN, a citizen of the United States, residing at St. Louis, in the State of Missouri, have invented certain new and useful Improvements in AutomaticGut-Ofif-Valve Gearfor Steam-Engines; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being bad to the accompanying drawings, forming a part of this specification.

This invention has for its objects, first, to provide a simple, cheap, and durable mechanism for automatically regulating the supply of steam to the engine to suit the work that is being performed; second, to provide a safety device to prevent the engine from running away when from any cause the governor-belt becomes broken or unshipped from its pulley; and this invention consists-- First. In the provision at the lower end of the governor-stem of a double-ended wedgeblock having a movement between two pivoted links which bear against two pivoted bars at the ends of a forked bar that operates the governor-valve or a set of puppet-valves, &c.,'

controlling the supply of steam to the engine, the arrangement being such that an upward or a downward movement of said block willshift the point of engagement with the toes of a rock-arm that receives its motion from an eccentric on the engine-shaft, and which, when the said block is fully raised or lowered, will force them entirely out of engagement with the operating-toes of said rock-arm, and thereby allow the governor-valve to remain closed and shut off the steam-supply to the engine, as will hereinafter more fully appear.

Secondly. In the provision,in connection with the counterbalance weight or ball of the governor, of a swinging bearing-bar, under which the inner end of the ball-rod plays, and by means of which a too great upward movement of the same is prevented during the normal operation of the governor. This bearing forms part of the journal-bracket that carries the governor pulley-shaft, pivoted on the gover nor-frame in any suitable manner, the arrangement being such that when the governor-belt is in its proper position the bearing-bar (above mentioned) will be held over the inner end of the ball-rod to prevent a full upward move- .transversely to Fig. 1.

ment of the same; but when from any cause the governor-belt parts or becomes unshipped from its pulley, said journal-bracket will be swung around by a spring so as to carry the bearing-bar out of engagement with the ballrod in order to allow the same to rise at once and shut off the. supply of steam to the engine, the arrangement being such that the shutting oft of the steam to the engine is accomplished instantaneously and does not depend upon the return of the governor-balls to their down position, which requires time, owing to the centrifugalmotion previously imparted to them.

Thirdly. In certain details of construction, as will hereinafter more fully appear.

[11 the drawings, Figure 1 is-a vertical section, illustrating myinvention as applied to a governor-valve. Fig. 2 is a vertical section Fig. 3 is a horizontal section at line w a. Fig. 4 is a detail view, il

lnstrating my invention as applied to apuppet valve, &c., engine.

Similar letters of reference indicate like parts in the several figures. V

r A. represents a governor of any suitable construction, the stem a of which is provided at its lower end with a double-ended wedge-block, B, I

moving between the two pivoted links 0, as shown. These links have outwardly-project ing' toes 0, which bear against the links D, pivoted to the lower ends of aforked sliding bar, E, which is connected to and operatesthe governor valve F by a lever G, or other equivalent means.

d are springs acting through rods d to force the links D inwardly, as clearly indicated in Fig. The frame E and bars D are lifted at each stroke of the piston by means of a'rockarm, H, having liftin g-toes h,which engage under the links or bars D, as shown. This rockarm may receive its motion from an eccentric on the engineshaft or from a moving portion of the engine, as desired.

The construction above described is adapted for attachment to an ordinary slide-valve engine, and in cases of puppet-valve engines, &c., the links D may be pivoted directly to the lifting-arms D, of the said valvesin manner indicated in Fig. 4.

b is a lug on the block B, which has movement in an elongated slot in the casing, the

purpose being to prevent any side play of said block when in use.

The governor-valve is formed with an upper andlowervalveandseat,jf,the upperone being the larger, and steam is admitted into the chamber above this valve by means of a screw-plug valve, f so as to adjust the pressure of steam on the top of the valve. With this construction all fluttering of the valve onits seat is prevented, and the quickness and force with which it closes can be readily adjusted and controlled.

The operation of my improvement thus far described is as follows: While the engine is properly performing its work the wedge-block Bis comparativelystationaryandthegovernorvalve is fully opened and closed at each stroke of the engine. When the speed of the engine increases the governor forces down this block B,which spreads the links 0, and through them the links D, and shifts the point ofengagement between the ends of said links D and the toes h of the rock-arm, so that the links will not be lifted as high as when said links are fully in before the toes of the cam pass from under them and allow them to drop; and as the amount of opening of the governor-valve depends upon the amount of movement of these links it will be seen that the steam will be automatically cut off at difi'erent points of the stroke to suit the work being performed, the adjustment being automatic and in proportion to the increase in speed; and the construction is such that any great increase in speed will entirely disengage the links D from the rock-arm H to allow the governor-valve to remain closed until the engine has regained its normal speed. This construction possesses the advantageous feature that the steam is automatically cut off to suit the work performed by the engine. When the speed of the engine increases the links D will be pushed out so as to be lifted a less distance, and consequently they'will drop sooner and shut off the supply of steam, the amount of lift of said links and the consequent change of time in cutting off steam being antomatic and depending entirely upon the speed of the engine.

The following construction and arrangement of parts is used as an instantaneously-acting safety device to prevent the running away of the engine when the governor-belt breaks or becomes unshipped from its pulley. The bracket or journal I, that carries the shaft of the governor-pulley, is pivoted to the governor-frame A, as shown, and is provided with a curved bearing-bani, which rests over the inner end of the counterbalance-rod J to control the amount of upward movement of the same during the normal working of the engine.

is a spring tending to force the frame I around on its pivot, so as to carry the bearingbar 2' out of engagement with the end of the counterbalance-rod, which tendencyis prevented during the proper working of the engine by the governor-belt holding the parts in position; but on the breakage, &c., of the governor-belt the parts are released and the counterbalancerod allowed to rise and in its movement lift the governor-stem a, and with it in turn the wedge-block B, which pushes the links D out of engagement with the toes of the rock-arm H, so as to allow the governor-valve to drop to its seat and remain closed, thus stopping the engine. By this construction the weight of the counterbalance is brought into action when required to overcome the centrifugal momentum of the governor-balls and cause them to imme' diately assume their down position and shut off the supply of steam to the engine.

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

1. In an automatic cut-otffor steam-engines, the governor-stem a, provided with a wedgeblock, B, in combination with the adjustinglinks 0 and adjustable links D, connected to the valve or valves of an engine and operated by a rock-arm, H, substantially as described, and for the purpose set forth.

2. The combination of the plug-valve constructed and arranged as shown, with the governor-valve F, having seats ff, all as herein described, and for the purpose set forth.

3. The bracket I, pivoted to the governon frame and provided with a bearing-bar, i, in combination with the counterbalance rod and weight, as described, and for the purpose set forth.

Signed at St. Louis, in the State of Missouri, this 4th day of January, 1881.

JOHN W. MORGAN.

In presence of- ROBERT BURNS, T. D. Pownns LA PAER.

Images