US557515A - Air-brake - Google Patents

Description

(No Model.)

G. s. LEE.

AIR BRAKE.

No. 557,515. Patented %ar.'31, 1896.

UNITED STATES PATENT OFFICE.

GEORGE S. LEE, OF HAVTHORNE, NEW JERSEY, ASSIGNOR TO THE NATIONAL AIR-BRAKE COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEXV JERSEY.

AIR-BRAKE.

SPECIFICATION forming part of Letters Patent No. 557,515, dated March 31, 1896.

Application filed February 19, 1896. Serial No. 579,874. (No model.)

T0 at whom it may concern.-

Be it known that I, GEORGE S. LEE, a citizen of the United States, residing at Hawthorne, in the county of Passaic and State of New Jersey, have invented certain new and useful Improvements in Air-Brakes; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilledin the art to which it appertains to make and use the same.

My invention has relation to automatic governors for air-brakes, and has for its object the provision of novel means for automatically connecting and disconnecting the moving parts of a pump from the mechanism by which it is operated, the automatic connection and disconnection of. the pump and its operating mechanism being effected by the variation of the air-pressure due to the alternate accumulation of pressure by the pump and the reduction of pressure proceeding from the operation of the brake. v

My invention consists in the novel construction, combination, and arrangements of parts hereinafter described.

Referring to the accompanying drawings, Figure 1 is a sectional View of my improved governor, and Fig. 2 a sectional view on the line as w of Fig. 1.

A designates a cylinder having a head A with stuffing-box A through which passes a piston-rod A carrying a piston A A lever F is pivotally connected to the end of the piston-rod A and is also connected to the clutch or other connecting devices which are interposed between the moving parts of the pump and its actuating mechanism.

Upon the end of the cylinder A is screwed a valve-chamber B, which is in the form of a T coupling and contains a cylindrical piston-valve composed of two parts B B a screw-threaded pin on the part B, screwing into a screw-threaded hole in the part 13*, a packing B being interposed between these parts B B One end of the chamber B is closed by an adjustable screw-plug B and a spring B is interposed between the plug B and the piston-valve, so that by the adjust ment of the plug the resistance of the spring may be increased or diminished.

A port 0 leads from the valve-chamber to the cylinder, and the part B of the valve is formed with a circumferential groove Z), from which passages 17 5 lead to the hollow interior of the part B and a passage b leads from the interior of the valve-chamber to the open air.

The part B of the piston-valve is formed with a cage O, which limits the movement of the piston-valve. The open end of the valvechamber B screws onto a coupling D, which also receives a pipe E leading from the reservoir in which the compressed air is stored, and a pipe F leading to a valve-chamber G on the side of cylinder A. The valve-chamber G contains a cylindrical piston-valve G, made up of alternate rings 9 g g of packing material and metallic disks g g g g, all fixed on a common stem 9 The upper end of the valve-chamber G is closed by an adjustable screw-plug G and a spring G is interposed between the screw-plug and the upper end of the valve G, so that by the adjustment of the plug the pressure of the spring can be regulated.

The disks 9 g of the valve G are formed with circumferential grooves 9 9 and apassage H in the walls of the chamber G leads from the space in the chamber below the valve G to a point where it communicates with the groove 9 when the valve G is in the position shown in the drawings. A port *5 leads from the interior of cylinder A' to the interior of the chamber G, and a port 2' leads from the chamber G to the open air, the position of these ports being such that when the valve G is raised by the increase of pressure in the pipe F leading from the reservoir the ports 11 '21 and the groove 9 will coincide and will form an unobstructed passage from the interior of the cylinder A to the open air.

Operation: The parts being in the posi tions shown in the drawings, let it be supposed that the air in the reservoir is below the pressure required for effective working and the pump is at Work. \Vhen the airpressure reaches a certain point, the valve G rises and opens the communication through c 01 g from the upper part of cylinder A to the open air. This position is maintained until the air-pressure reaches the maximum, whereupon the valve B B is forced back against the resistance of the spring B closing the port b and opening the passage C to the interior of cage part B, and allowing the air to enter the cylinder A below the piston and elevate the same. The position of parts last described is maintained while the pressure is at the maximum, and the pump, having been stopped by the elevation of the piston, remains inactive so long as the piston remains in its elevated position. The gradual decrease of the air-pressure due to the operation of the brake first results in the move ment of the valve B B which closes communication between the reservoir and the lower end of cylinder A and opens communication through port b to the open air. The further decrease of pressure to the minimum allows the descent of valve G to the position shown in the drawings, whereupon the air passes up from pipe E, through pipe F and passage H, thence through groove 9 and a port i and entering above the piston A pushes it down and starts the pump. The operation of connecting and disconnecting the pump-operating mechanism is thus accomplished in a perfectly automatic manner solely by the variation in pressure produced by the operation of the brake.

Having described my invention, I claim- 1. In an automatic governor for air-brakes, the combination with a cylinder and piston of an adjustable automatic valve controlling the inlet and exhaust on one side of said piston and a second separately-adjustable automatic valve controlling the inlet and exhaust on the other side, substantially as described.

2. In an automatic governor for air-brakes, the combination with a cylinder and piston of two automatic valves both communicating with a common source of compressed air and with said cylinder and operated positively by pressure of air, one of said valves being adapted to operate under a predetermined low pressure, and the other to operate under a predetermined high pressure, substantially as described.

In testimony whereof I aflix my signature in presence of two witnesses.

GEORGE S. LEE. Vitnesses THos. A. CoNNoLLY, ANTHONY A. GoNNoLLY.

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