US2009881A - Spring loaded valve - Google Patents

Description

July 30, 1935. w FOURNESS 2,009,881

SPRING LOADED VALVE Filed Sept. 22, 1930 k/i/frea 50277865 A #arney Patented July 30, 1935 UNITED- STATES PAT 7 SPRING LOADED VALVE Wilfred Fourne ss, Oakland, Calif assignor, by mesne assignments, to Edward G. Burghard,

New YorkpN.

' Application September 22, 1930, Serial No. 483,593

2 claims. (01. 230-185) This? invention relates to compressors, and more particularly-to what is herein termed a spring loaded valve to beused with the mechanism of my copendingcase to a Compressor mechanism, Serial No. 31 8,7-36 ,-filed1 November 12', 1928', and which is a continuation in part thereof. 7

In compressor mechanisms of the type above referred to, long or extended periods of inactivity cause oil, in which themechanism is immersed, toseepbetween the walls of the piston and cylinder, and accumulate in the latter. When-the mechanism is started up again after the period of inactivity, the oil in the cylindermust be first subjected to pressure, and if no means of ready egress therefor is provided, the mechanism will stall; In addition, if there should be a sudden flood-ingot liquid on the return line, there'would be a consequent sudden overloading or break down of the mechanism, unless some meansare present for relievingagainst such an occurrence;

It is an object of this. invention to provide a mechanism which will relievethe pressure set up by the compression of'a liquid with the cylinder.

It is a further object of this: invention to provide a valve mechanism which i'sresponsive to unusual and abnormal pressures in the cylinder whereby the pressure therein is relieved.

It is a further'object of this invention to pro vide a device simplev'indesig'n and construction and inexpensive to manufacture. J

My invention possesses many: other advantages; and has other objects which may be made more easily: apparent fromfa consideration of one embodiment of my invention. For this purpose I have shown a form in the drawing accompanying and forming part of the present specification. I shall now proceed to describe this form in detail, which illustrates the general principles of my invention; but it is to be understood that this detailed description is not to be taken in a limiting sense, since the scope of my invention is best defined by the appended claims.

Referring to the drawing:

Figure 1 is a sectional view of a reciprocating compressor mechanism embodying my invention; and

Fig. 2 is a fragmentary sectional view taken substantially along the-plane 22 of Fig. 1.

The compressor mechanism is shown as located in a housing [0 having a removable end wall II. The inlet for the compressor is provided through a pipe I2, and the outlet through a pipe l3.

The compressor proper is conveniently supported on wall H, which has a shoulder l4; over which the main compressor body IE5 is accome modated. The compressor can be driven by any appropriate source ofmotion, as by the aid of shaft l6 passing through the fluid tight packing gland ll which is provided in a hub or boss 18- on wall N. This shaft extends into the interiorof .ie housing 10, and mechanically drives the piston devices utilized in the compressor.

The compressor body 45, as described in my co: pending application above referred to, has a sub stantially rectangular-central portiont9; from whichextend, in diametrically opposite directions, the cylinder blocks 20, 2|. Each ofthese cylinder blocks has a large bore 22, 23 radial to the axis of the shaft ll, for the accommodation of the mainpistons 24, 25 that are reciprocated therein. The blocks 20, 2| are also, provided withvalve bores 26, 21 that are parallel and close to bores 22, 23, and that accommodate the valve piston 23, 29 for the control of inlet and outlet ports. for the cylinders 22, 23. 'All of the pistons 24', 25, 28, 29 can'be' provided with grooves such'as 3G. to facilitate oiling.

The pistons 24, 25 are reciprocated as. follows: Shaft H5 is journaled inside of housing I10. ina cap. or cover member 31 that fits, over the end of the rectangular portion *l 9.to,provide a fluid tight enclosure therein. Shaft lBtcarries an eccentric portion 32 having a small flange 33. The eccentrio is freely rotatable in an eccentric block 34. This block is; embraced by aframe slide 35 in a manner fully described in my above mentioned copending application; that is, a rotation of eccentric 32 causes a side to. side motion of block 35, and a consequent vertical reciprocation of slide 36. As pistons 24, 25 are mechanically fastened to slide 35, as by a dovetailed conneetion 3%, the reciprocation of the slide causes a reciprocation of the pistons and a consequent compression of the fluid fed to the compressor.

The fluid to be compressed in the cylinders 22, 23 enters therein through ports 31, 38 which are open for a time that falls Within the time corresporiding to the piston movement out of the cylinder space. On the compression stroke, port 31 or 38 is closed, and the fluid is compressed in the cylinder space. After a definite piston movement into the cylinder space, port 31 or 38 again opens, but now communication is established with outlet passages 39 or 40. Since pistons 24, 25 are on opposite sides of slide 35, one of them is on its suction stroke while the other is on its compres-j sion stroke. Each of the cylinders 22, 23 has a cap referred to as by 4|, 42 in order to define the 7 cylinder spaces, and for a purpose to be hereinafter described.

The caps 4|, 42 are formed of main body members 43, 44 having central depending portions 45, extending into and snugly contacting with the inner walls of the cylinders. An opening extends through each main body member and terminates at the lower portion thereof in a valve seat 41, 48. Valve closures 49, 5B are arranged to coact with the valve seats to form a valve. The valves are maintained in a normally closed position by means of strong springs 5|, 52 encircling the valve stems 53, 54 and acting against the valve closure members 49, 50. Plugs 55, 56 are screw-threaded into the upper portion of the openings extending through the main bodies 43, 44 and act to confine the springs 5|, 52. Communication is established between the cylinders 22, 23 and the space 51 by means of passageways 58, 59 in a manner to be hereinafter described. It is to be understood,'that piston valves 28, 29 aremounted on an eccentric 56 in a manner similar to pistons 24, 25; and that by appropriate angular arrangement between eccentrics 32 and 60, the proper sequence of the valve opening and closing actions with respect to the movements of the pistons 24, 25, can be secured. As the action of the pistons and piston valves to control the ports 31, 38, 39, and 40 havebeen fully set forth in my copending case above referred to, no further description thereof is deemed necessary. In the drawing, no attempt is made to indicate the correct lead'or lag of one eccentric with respect to the other, however, it is to be understood that such lead or lag is essential to obtain the proper opening and closing of the inlet and outlet ports. In order to fully comprehend the function of the spring loaded valves 49, 50, particular attention is directed to the relation of piston 25 and piston valve 29 to port 38. Let us assume that the compressor has been inactive for some time, and that oil has'seeped into the cylinder 23. It will be noted that piston 25 is just beginning its compression stroke and in that position port 38 is closed by piston valve 29. As the piston 25 begins compressing, it first acts to subject the oil to pressure in cylinder 23; If there were no provisions for the spring valve, there would be no escape passageway provided for the com pressed oil, and the pressure built up in the cylinder 23 would immediately stall the motor. However, by my arrangement, the pressure built up by the compressed oil issufficient to open the valveclosure 50 against the action of the spring 52, and thereby permits the oil to flow out of the relief port 50. Of course during normal running conditions, very little oil is in the cylinder 23 and only the expanded refrigerant is compressed. The pressure set up during this period is not suflicient to overcome the action of the spring 52 and the compressed gas flows out of the port 38 which is opened when the piston valve 29 has been moved in proper cyclical sequence with respect to piston 25. I

It is not an infrequent occurrence for liquid to be carried into the inlet l2 along with the gas refrigerant. The liquid would then flow into the cylinder '22; and also into cylinder 23 through the medium of. the pipe connection 6|, and cause a sudden overloading or breakdown of the compressor. However, the spring loaded valve would operate to relieve the pressure set up by this return compressed liquid in a manner hereinabove described.

I claim:

1. In a mechanism for compressing a gaseous refrigerant, a cylinder, a piston movable therein for compressing the refrigerant in the interior of the cylinder, means forming an outlet valve from the cylinder, means whereby a lubricant is supplied to the cylinder, a yielding valve closure cooperating with a port in the cylinder wall, said port being in communication at all times with the cylinder interior, said closure being so constructed that the closure opens only upon abnormal pressure in the cylinder and remains closed during normal operation-of the mechanism, and means forming a collecting space communicating with said port when the closure opens, said space also serving as a reservoir for the lubricant to the cylinder.

2. In a mechanism for compressing a gaseous refrigerant, a cylinder, a piston movable therein for compressing the refrigerant in the interior of the. cylinder, a positively driven valve mechanism controlling an outlet from the cylinder in timed relation to the piston movement, means whereby a lubricant is supplied to the cylinder, a valve closure cooperating with a port in the cylinder wall, said port being in communication at all'times with the cylinder interior, means for urging the valve closure to closing position with a force such that abnormal pressures only, can open the closure, and means forming a collecting space communicating with said port when the closure opens, said'space also serving as a reservoir for the lubricant supplied to the cylinder.

WILFRED FOURNESS.

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