US1169305A

US1169305A - Electric pump-governor.

Info

Publication number: US1169305A
Application number: US?73?9214A
Authority: US
Inventors: Walter V Turner
Original assignee: Westinghouse Air Brake Co
Current assignee: Westinghouse Air Brake Co
Publication date: 1916-01-25
Anticipated expiration: 1933-01-25

Description

W. V. TURNER.

ELECTRIC PUMP GOVERNOR. APPLICATION FILED Nov 25, 19l4.

1, 169,305, Patented Jan. 25,1916.

% lull III! ihh I 1 in I v .H' l

L "a "WWW. "R! W 5 i1 I s 5 6 l 3 WITNESSES INVENTOR WALTER V. TURNER, OF EDGEWOOD, PENNSYLVANIA, ASSIGNOB TO THE WESTING- HOUSE A111 BRAKE COMPANY. F

01: PENNSYLVANIA.

WILMERDING, PENNSYLVANIA, A CORPORATION ELECTRIC PUMP-GOVERNOR.

Specification of Letters Patent.

Patented Jan. 25, 1916.

Application filed November 25, 1914. Serial No. 873,892.

To all whom it may concern:

Be it known that I, M rna V. TURNER, a citizen of the United States. residingat Edgewood, in the county of Allegheny and State of Pennsylvania, have invented new and useful Improvements in Electric Pump- Governors, of which the following is a specification.

This invention relates to electric pump governors, and more particularly to the type shown in Patent No. 1,036,886 of H. M. P. Murphy, dated August- 27, 1912, and in which the operation of the governor is'effected by means of puppet valves.

The principal object of my invention is to provide an improved governor of the above type, in which possible effect of wear and consequent leakage in producing unsatisfactory operation, is reduced to a minimum.

in the accompanying drawing. the single figure is a central vertical section of an electric pump governor embodying my improvements.

As shown in the drawing, the pump govcrnor may comprises casing 1 having apiston chan'iber 2 containing apiston 3 for opcrating a pump controlling device or switch 4, the switch piston 3 being subjectto the pressure of a spring 5 tending to close the switch 4.

Fluid from the pump or storage reservoir is supplied through pipe 6 and passage 7 to the inner face of a cut-in valve piston 8 subject on the outer face to the pressure of an adjustable spring 9 tending to shift the valve piston to a seat 10. Fluid under pressure also flows through passage 7 to the inncr face of a cut-out valve piston 11 which is normally held to a seat 12 by the action of an adjustable spring 13.

The spring chamber 14 of the cut-out valve piston 11 is provided with a passage 15 having branch ports 16 and 17 controlled by the movement of the cut-in valve piston S and when the cut-out valve 11 is on its seat 12. communication is open from spring chamber 11 through ports18, annular groove 1 and passage 20 to the switch piston chamber The spring chamber 21 containing the cut-in spring 9 is open to a restricted atmospheric exhaust port and when the vulvc piston 8 is or? its rear seat 23, communication is open from the spring chamber 21 through a passage 24 to the switch piston chamber 2.

The tension of the

springs

9 and 13 may be substantially equal and the area of the cut-out valve piston 11 exposed to pump pressure at the seat 12 bein greater than the exposed area of the cut-1n valve piston 8, as the pump pressure rises, the cut-out valve piston 11 will be unseated beforethe cut-in valve piston. As soon'as the cut-out valve piston 11 lifts from its seat 12, the full area thereof is exposed to pump pressure, so that the same quickly moves to the extreme cut-out position. The movement of the cut-out valve piston uncovers passage'25, so that fiuid'at pump pressure is admitted to the chamber 26 and since the full area of the cut-in valve piston 8 is now subject to pump pressure, the resistance of the spring 9 is overcome, and the cut-in valve piston is then quicklyshifted to its rear seat 23. In this position, the escape of fluid from chamber 27 to chamber 21 and exhaust port 22 is prevented. v v

Vhen the cut-in valve piston 8 moves to its rear seat 23, port '1? is uncovered, so that fluid at pump pressure can flow from chamber 26, through port'17 and passage 15 to the cut-out spring chamber 14. T he fluid pressures on opposite sides of the cut-out valvev piston 11 are thus equalized, thereby permitting the spring 13 to shift the cut-out valve piston to its seat 12. The cut-in valve piston 8 remains in the cut-out position and fluid at pump pressure can therefore flow through port 17, passage 15, ports 18, groove 19, and passage 20 to the switch piston chamber 2, forcing the switch piston 3 and the switch 4 to the cut-out position and stopping the compressor. The cut-in valve piston 8 will remain in cut-out position until the pump pressure acting in chamber 26 has fallen to a point at which the spring 9 exerts the balance of power and then the valve piston 8 hits from its seat 23. This allows fluid at pump pressure flowing from the piston chamber 2 through passage 24 to enter the spring chamber 21 and since the exhaust port 22 is restricted, the pressure in said chamber will build up to a point such that the quick movement of the cut-in valve piston 8 to its seat 10 is effected by the spring 9. In this position, fluid also e. haus'ts from piston chamber 2 through passage 20, groove 19, ports 18, passage 15, chamber 27, to spring chamber 21 and exhaust port 22, so that fluid is quickly released fronrthe switch piston chamber 2 and the switch piston with the switch 4 are shifted to cut-in position by the spring 5, again starting the compressor. I

In the cut-out position of the cut-out valve piston 11, a groove 28 connects passage 25 with an annular groove 29 in the valve piston which communicates with a passage 30, leading to the passage 2-1, so that leakage past the seat 12 can escape, either through the exhaust port 22 or to the spring chamber of the switch spring 5, which is open to the atmosphere. This will also permit escape of leakage past the seat 10 into chamber 26, so that leakage past either the cut-out or the cut-in valve pistons will be provided for and thus erratic action or premature operation of the governor prevented.

It will be noted that fluid is not admitted to the switch piston until the cut-in valve piston 8 has shifted to cut out position and the cut-out valve piston 11 has been returned to the normal position on the seat 12, so that movement of the switch piston to cut-0ut position is assured regardless of possible leakage past the valve pistons.

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. A pump governor comprising a pump controlling device, a piston for actuating said device, a cut-in and a cut-out valve piston each having a cut-in and a cut-out position, communication through which fluid is admitted to the control piston being established when the cut-in valve piston is in its cut-out position and the cut-out valve in its cut-in position.

2. A pump governor comprising a pump controlling device, a piston for actuating said device, a cut-in valve piston subject to the opposing pressures of the pump and an adjustable spring and operated by pump pressure for opening a communication through which fluid is admitted to the control piston, and a cut-out valve iston subject to the opposing pressures of the pump and an adjustable spring and operated by the spring for also opening said communication. I

3. A. pump governor comprising a pump controlling device, a piston for actuating said device, a cut-out valve piston subject to the opposing pressures of the pump and an adjustable spring for controlling a passage through which fluid is admitted to the control piston, and a cut-in valve piston sub ject to the opposing pressures of the pump and an adjustable spring contained in a spring chamber having a restricted exhaust port and adapted in one position to admit fluid to said passage and in another position to open communication between the spring chambers of the cut-in and cut-out springs.

l. A puinp governor comprising a pump controlling device, a piston for actuating said device, a cut-out valve pistonsubject to the opposing pressures of the pump and an ad ustable spring, and a cut-in valve piston subject to the opposing pressures of the pump and an adjustable spring and operated upon movement of the cut-out valve piston to cut-out position to admit fluid to a passage for supplying fluid to the control, piston, the cut-out valve piston beingshifted upon movement of the cut-in valve piston to the fluid supplying position, to a position in which communication is opened through said supply passage to the control piston.

In testimony whereof I have hereunto set my hand.

WALTER V. TURNER. lVitnesses A. M. CLEMENTS, S. V. KEEPER.