US713631A - Discharge-valve for compressors. - Google Patents

Description

N0. 7|3,63l. Patented Nov. l8, I902.

F. W. GORDON.

DISCHARGE VALVE FOR COMPBESSURS.

(Application filed Mar. 17, 1902.) (No Model.)

Witnesses: Inventor I o W W I S M 5. 13M Attorney w: mums PETERS co. gNom-urm, WAsmNsYou, n. cy

ll ivirnp STATES Parnivr @nricnt FREDERICK W. GORDON, OF HARTFORD, CONNECTICUT.

DISCHARGE-VALVE FOR COMPRESSORS.

SPECIFICATION forming part of Letters Patent No. 713,631, dated November 18, 1902.

Application filetLMarch 17, 1902. Serial No. 98,543. (No model.)

of a portion of the cylinder of an air-compressor fitted with my improved dischargevalve.

In the drawing, 1 indicates the compressorcylinder, 2 its piston, 3 its piston-rod, 4 its cylinder-head, 5 its discharge-chamber, 6 the outlet from the discharge chamber, 7 a passage through the cylinder-head placing the compressor-cylinder in communication with the discharge-chamber, all of the parts thus far referred to being of ordinary construction and subject to ordinary and proper modifications; S, the discharge-valve disposed within the discharge-chamber and seating in the passage 7 and opening toward the discharge-chamber; 9, the stem of the valve projecting outwardly through the outer wall of the discharge-chamber; 10, a rocker fitted on the dischargechamber and having one end connected with valve-stem 9; 11, a tappetstem extending through the discharge-chamber parallel with the axis of the compressor, its outer end being connected with rocker 10 and its inner end projecting into the compressor-cylinder in position to be in contact with the compressor-piston when the latter is at the end of its stroke and valve Sis closed and adapted as valve 8 opens to project still farther into the compressor-cylinder; 12, a valve piston supported by the dischargechamber concentric with valve-stem 9; 13, a valve-cylinder formed upon the back of the discharge-valve and fitting valve-piston 12 with proper air-tightness, and 14: a tube surrounding tappet-stem 11 to prevent leakage around the stem from the discharge-chamber.

Assume the compressor to be working and the discharge-chamber to be under pressure and that the parts are in the position indicated in the drawing, the discharge-valve 8 being closed and the compressor-piston ready to begin its suction-stroke to'the right. As the compressor-piston moves to the right, the air of suction following it through the usual inlet-valve, (not shown,) discharge-valve 8 is held closed by discharge-pressure upon its back preponderating over suction-pressure upon its front. Under these conditions the compressor-piston completes its stroke to the right and reversing begins its compressive stroke, the pressure in the compressor-cylinder constantly rising as the compressor-piston advances. Cylinder 13 is full of air under atmospheric pressure, due to leakage-way past stem 9, and consequently the pressure in the discharge-chamber is acting upon only that annular portion of the valve exterior to piston 12 or on an area represented by that of the valve minus that of piston 12. WVhen the increasing pressure in the compressor-cylinder reaches that point at which it acting 011 the inner face of the valve will preponderate over the discharge-pressure acting on the back of the valve plus atmospheric pressure in cylinder 13, acting on the back of the valve, then the valve will suddenly fiy open, the air trapped in cylinder 13 acting as a cushion,

but soon leaking out, so that the cushioning air becomes reduced to that of the atmosphere. The areas of the valve and piston 12 may beso proportioned that this sudden opening of the valve will take place when compression reaches the discharge-pressure or so that it will anticpate it. The valve having suddenly opened remains full open while the compressor is discharging into the dischargechamber, tappetstem 11 having protruded into the compressor-cylinder when the valve opened. \Vhen the compressor-piston nears the end of its compressive stroke, itmakes contact with the inner end of the tappet-stem and gives the valve a movement of closure, the valve being practically closed when the compressor-piston shall have reached the end of its stroke and closing with positive certainty and completeness under the influence of discharge-pressure upon its back when the compressor-piston begins its suction -stroke. The leakage of air from cylinder 13 may be provided for by a little extra looseness of stem 9 in its hearing or by any equivalent arrangement, and the general disposition of cs- ICO sential parts is manifestly subject to numerous constructional modifications without departure from the invention.

I claim as my invention 1. In discharge-valves for compressors, the combination, substantially as set forth, with a compressor-cylinder, compressor-piston, discharge chamber, and discharge valve opening to the discharge-chamber, of a piston and cylinder disposed at the back of the discharge-valve and arranged to detract from the area thereof subject to discharge-pressure, a tappet projecting into the compressorcylinder and adapted to be engaged by the compressor-piston as it nears the end of its compressive stroke, and connections between said tappet and the valve whereby the movement of the tappet under the influence of the compressor-piston causes the practical closure of the valve.

2. In discharge-valves for compressors, the combination, substantially as set forth, with a compressorcylinder, compressorpiston, cylinder-head, discharge-chamber at the cylinderhead, and discharge valve disposed Within the dischargechamber and closing toward the compressor-cylinder, of a piston fixed within the discharge-chamber and projecting toward the discharge-valve, a cylinder engaging said fixed piston and connected with the valve, a valve-stem, a tappet-stem projecting into the compressor-cylinder and adapted to be engaged by the compressor-piston as it completes its compressive stroke, and a pivoted rocker connected with the valve-stem and tappet-stem.

FREDERICK W. GORDON.

Witnesses:

W. M. S'roRRs, CHAS. T. MINGO.

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