US802886A - Valve mechanism. - Google Patents

Description

PATENTED OCT- 24, 1905.

N m v v 1 H N a m G P REIBOLD VALVE MECHANISM.

APPLICATION FILEDIBB. 21. 1903.

WITNESSES.-

lUNlTED STATES PATENT Specification of Letters Patent.

Patented Oct. 24., 1905.

Application filed February 21, 1903. Serial No. 144,375-

. Alabama, have invented new and useful improvements in Valve Mechanism, of which the following is a specification.

My invention relates to new and useful improvements in valve mechanism especially adapted for use in connection with the cylinders of locomotives; and its primary object is to provide an auxiliary cut-off whereby steam may be directed into one or both ends of the cylinder, as desired.

It is a well-known fact that a large amount of power is lost during the period when the crank-pins of the drive-wheels of locomotives are traveling below the axles. By means of my invention the power which is usually lost in this manner is saved. The invention consists in providing a pivoted cut-off which is located in the front inlet-port of the cylinder and is adapted to be operated from the cab of the engine by suitable mechanism connected therewith. By means of this cut-off steam can be prevented from entering the cylinder through the inlet in which the cut-ofl is located and power will be applied to but one side of the piston.

The invention further comprises the novel features of construction and combination of parts more fully hereinafter described.

In the accompanying drawings, Figure 1 is a longitudinal section through a portion of an engine-cylinder and its steam-chest. Fig. 2 is an enlarged detail sectional view of the auxiliary valve, showing the same in closed position. Fig. 3 is a similar view showing the auxiliary valve in position.

Referring to the drawings by referencenumerals, 1 designates a cylinder having inlet-ports 2 and 3, respectively, which open into a steam-chest 4. A slide-valve 6 of the usual construction is mounted within the chest and operated by means of a rod 7. A preferably semicircular recess 8 is formed within one side of the port 2, the other side thereof being provided with a recess forming a shoulder 7 to provide a valve-seat. Centrally pivoted within the recess 8 is a valve 8, being mounted therein on a stem 9 and which is adapted to be swung across the port 2 to prevent the passage of steam therethrough. The valve 8 when in closed position has its forward end placed in engagement with the valveseat 7 and when in opened position it lies within the recess 8, placing the lower surface thereof flush with one wall of the port 2, whereby the free and unobstructed passage of steam therethrough is provided for. The stem 9 is provided with an arm 10, shown in dotted lines, and to which is secured a rod 11 extending into the cab (not shown) of a locomotive, whereby the cut-ofl may be readily operated by the engineer.

It will be observed that the oppositely-projecting wings of the valve are of greater length than the diameter of the port 3, so that the free end of one of the wings of the valve is adapted to seat in the depression 7 when the valve is closed, with the free end of the other wing impinging the wall of the recess 8, whereby the valve is practically balanced in operation as inclosing the back pressure and direct pressure operated upon both wings in opposite directions, while in the opened position the pressure of the steam ordinarily retained within the recess acts upon the valve to render easy the operation of the valve. This would not be the case if the valve titted or approximately fitted the semicircular recess, and, furthermore, the opening of the valve is assisted by the pressure upon the wing of the valve moving within the recess, which pressure is effective as soon as the exterior wing of the valve has moved from its receiving depression and slightly opened a passage through the port. These advantages are gained by the use of a flat valve with double wingsin conjunction withasemicircular recess, which is closed by the valve, when the valve is in opened position, as shown in the drawings in dotted lines. It will be observed that the axis of the valve is disposed in the center line of the recess 8,while the receiving depression 7 a is disposed upon one side of the plane of said line and is formed at one side with an abutting shoulder and upon the opposite side with an inclined or beveled guide-face leading thereto. By this construction the exterior wing of the valve when the valve is moving to closed position is guided to rest at its free end against said shoulder, which retains the valve in an angular position relative to the axis or vertical center line of the recess 8, whereby the pressure of the incoming steam on the back or outer face of the wing within the recess 8 is utilized to hold the opposite or exterior wing in engagement with the shoulder of the depression, thus holding the valve tightly seated and preventing any leakage of steam through the port when the valve is closed.

The operation of the device may be explained in the following manner: WVhen a locomotive is in the act of starting or traveling upgrade, the valve 8 is swung into such position as to permit the unobstructed passage of steam through the port 2. When, however, the locomotive is on a horizontal or down grade, the valve may be swung across the port 2 to prevent the passage of steam therethrough, the steam being adapted to enter only through port 3. The valve is swung into closed position when the piston has reached the limit of its inward movement within the cylinder, whereby a partial vacuum is created between the piston-head and end of the cylinder where the port 2 is located. This creation of a partial vacuum permits the reciprocation of the piston-head within the cylinder, as the pressure which would otherwise arise between the piston-head and the end of the cylinder where the port 2 is located is overcome. This arrangement tends to prevent the waste of power which occurs when the crank-pins on the d rivewheel of a locomotive are at points below the aXles that is, during the backward strokes of the piston. The valve can, if desired, be turned so as to partly or completely close the inlet within which it is located. The complete closing of'the valve can be determined by the striking of the valve against the valve-seat 7, which permits the valve being swung sufiiciently to close the port 2. The valve-seat also serves as a stop or resistance for preventing the valve 8 from being turned beyond closed position by pressure of steam when it is desired to have the steam enter the cyl= inder through port 3 only, as will be apparent.

In the foregoing description I have shown the preferred form of my invention; but I do not limit myself thereto, as I am aware that modifications may be made therein without departing from the spirit or sacrificing the advantages thereof, and I therefore reserve 1 the right to make such changes as fairly fall within the scope of my invention.

Having thus described the invention, what is claimed as new isln a device of the class described, an enginecylinder, a steam-chest, a port connecting said parts for communication and having opposite walls, one of said walls being provided with a substantially semicircular recess and the other with an oppositely-disposed depression presenting a shoulder or seat, a pivoted valve designed to normally overlie and close the mouth of the recess and movable to a position for closing the port, said valve being of a length greater than the maximum distance between the inner wall of the recess and the distant wall of the port and having its fulcrum so disposed between and relative to said walls that the ends of the valve will, when the latter is in closed position, bear respectively against said walls with one of its ends seated tightly in the depression and upon the seat, and means for operating the valve.

In testimony whereof Iaflix my signature in presence of two witnesses.

CONRAD P. REIBOLD. Witnesses:

G. A. HOFF, F. A. BLOODWORTH.

Images