US553776A - Valve mechanism - Google Patents

Description

(No Model.) 2 sheets-sheet 1.

D. COOPER.

VALVE MEGHANISM.

UNITED STATES',

PATENT OFFICE.

DYER COOPER, OF PHILADELPHIA, PENNSYLVANIA.

VALVE MECHANISNI.

SPECIFICATION forming part of Letters Patent No. 553,776, dated January 28, 1896. Application led January 3, 1894. Serial No. 495,497. (No model.)

To all whom, t may concern.-

Be it known that I, DYERVOOOPER, a citizen of the United States, residing in Philadelphia, Pennsylvania, have invented certainV Improvements in Valve Mechanism, of which the following is a specication.

The object of my invention is to simplify the construction of valve-operating mechanism of steam-pumps, &c., by making the piston open and close exhaust-ports, allowing steam to exhaust from either side of the valvepiston, as fully described hereinafter.

A further object of my invention is to cushion the piston when used especially in a vertical pump or drill.

In the accompanying drawings, Figure l is a longitudinal sectional view of suflicient of a pump illustrating my invention. Fig. 2 is a transverse section on the line 2 2, Fig. l; and Fig. 3 is a transverse section on the line 3 3, Fig. l.

I have shown in the drawings the pump arranged in a vertical position, but it will be understood that it can be arranged in a horizontal position Without departing from my invention.

A is the cylinder having heads A A2, and in the cylinder-casting are ports a a', through which the steam ,enters'and escapes.

a2 is the exhaust-passage, which is open to either port as dictated by the slide-valve D, and is open direct into the cylinder, this opening being covered by the piston B. This piston is preferably elongated, as shown, and secured thereto is a pistonrod B', which is attached to the pump-piston of the ordinary construction. In grooves in this piston are suitable packing-rings b b, and beyond the packing-rings at each end of the piston are exhaust-grooves h/ and b2, which align with passages from the steam-chest D as well as with the exhaust-port d2, as fully described hereinafter.

In the port a, extending in the present instance into the head A of the cylinder, is a valve c, which closes the port more or less when steam is exhausted, so as to cushion the piston on its downward stroke. This valve is regulated by an adj listing-screw c', by means of which more or less opening can be given to the port. The area of the passages d3 beyond the valve is equal to the area of the port a, so that the steam in its admission to the cylinder is not wire-drawn, the valve c simply controlling the exhaust. The valve is a disk-valve having stems which are guided in ways in the head of the cylinder.

' The slide-valve D is controlled by a piston E, made hollow in the present instance and having openings e to allow steam to enter the valve from the steam-chest D', and in each end of this piston are small holes e', through which steam is wire-drawn and enters the spaces x at each end of the steam-chest. The space communicates with a passage i, which extends some distance below the exhaust-port a2 and enters the cylinder at c", so that when the piston B is in the position shown in Fig. l at the end of its stroke the groove b2 will align with this opening t" and at the same time with the exhaust-port a2 and consequently exhaust the steam from the space at one end of the valve-piston B, and steam at the opposite end of the piston will consequently force the piston and its valve in the direction of the arrow, shifting the slide-valve- D, and the piston B will then move in the opposite direction. The piston will imme- .diately'cut'off the communication between the space and the exhaust-passage c2, and steam will flow into the space .fr from the steam-chest D. When the piston travels to the opposite end of the cylinder, the groove b will align with the opening '3 of the passage z'2, which will exhaust the steam from the space x at the opposite end of the valve-pistonE, and thus reverse the slide-valve.

By the above-described mechanism it will be seen that the valve-operating mechanism is contained within the steam-chest and is not liable to be injured or become disarranged. This valve mechanism, it will be understood, can be used for other purposes than operating steam-pumps.

I claim as my inventionl. The combination in valve mechanism, of the cylinder having a steam-chest, ports a a extending from the ends of the cylinder to the steam-chest, a central exhaust-passage opening into the steam-chest and opening into the cylinder, a piston adapted to the cylinder and having grooves which alternately communicate with the exhaust-passage, a slidevalve controlling the admission of steam to IOO and exhaust of steam from the cylinder, a similar piston controlling said Valve and having passages therein communicating with the steam-chest and with spaces beyond each end of the piston, said passages being of such diameter as to wire-draw the steam, and passages extending from each end space to a central point in the cylinder some distance from the opening into the exhaust-passage so that when the piston in the cylinder reaches either of the extreme positions one of the grooves in the piston will form a communication lbetween said passages and the exhaust-passage, substantially as described.

2. The combination of the cylinder A, pis

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