US1998852A - Differential pressure control valve - Google Patents

Description

April 23, 1935. F. smuem 1,998,852

DIFFERENTIAL PRESSURE CONTROL VALVE Filed March 16, 1934 2 Sheets-Sheet 1 Invenlor n I 5 6% mm was flllorney Aprifi 23, 1935. M o s 1,998,852

DIFFERENTIAL PRESSURE CONTROL VALVE Filed March 16, 1934 2 Sheets-Sheet 2 f9 I; Z a 5:5

- 2 z Y f I a. Q IESSUIPE A9 I 40 PI? V 676' P19683095 SIDE /8 sins sarily, adapted for Patented Apr. 23, 1935 oFrcE oneta Ross N ell-Lo EENTIAL PRESSE CQNCHEOL VALVE N. Y" assignor of? Application March it, sit, sci-in No. 715,962

This invention relates to an improved differential pressure control valve, that is an automatic shut off valve adaptable for installation in fluid and gaseous conductionlines.

Although the valve is susceptible of general usage in pipe lines carrying different kinds of fluids and mediums, it is especially, but not necesuse in a refrigerant supply line such as is connected to a conventional or typical compressor constituting apart of a power actuated refrigeration system, for example of the present day domestic type.

Stated more explicitly, the valve is expressly designed for use on the modern types of commercial and domestic refrigeration units using to rest in the crank-case, occasionally causing dangerous leakage of gas.

This vaporized refrigerant gradually condenses in the crank-case, and the lubricating oil therein, being lighter and floating upon the liquid refrigerant, is raised to such a'height that it'is thrown upward by the pistons,".and forced through the pistons and exhaust or flapper valves into the condensing coils, leaving the crank-case short of lubricant. When placed back in service, a system in which the above condition exists will invariably motor, unless a restriction is placed on the suction valve before starting.

As will be hereinafter made evident the principal noveltyis predicated upon the particular valve, that is the specific construction of said valve.

Other features and more readily apparent scription and drawings.

In the drawings:

Figure 1 is an elevational view showing a typical commercial compressor disclosing theimproved safety refrigerant control valve incorporated in the refrigerant supply line.

Figure 2 is a view, essentially in section, showing the valve per se.

- Fi ure 3 is a horizontal sectional view taken advantages will become from the following deapproximately on, the plane of the line 33 of Figure 2.

Figure 4 is an enlarged detail sectional and elevational view showing the valve stem and valve elements detachably connected thereto.

Referring now to Figure 1 of the drawings it will be seen that the compressor is denoted by fitting 9 and the supply pipe 8.

This valve is detailed in Figure 2 and by, referring to this figure it will be observed that it one end to provide a tool gripping nut I2, and having its upper or top portion iii of circular construction accommodate and facilitate attachment of a structed to-provide an orifice or valve seat l9.

body is formed with a neck 20 removable cap The features 20 and 2| serve primarily as a hand hole or means permitting had to the valve, valve stem and The-valve stem sioned to the requisite degree as conditions reof the fitting 9 shown tendant burnt out motors, blown fuses, carbonized systems due to entrance of excess heat. It is simple and economical, susceptible of expeditious in the existing or stock parts, simple to adjust and all adjustments are easily accessible. when properly adjusted it requires no further: attention throughout the life of the unit.

It is understood that although the invention is described as particularly adaptable for use in a refrigerant circulation line it is susceptible of adequate employment and proper utility in various other lines requiring the use of a substantially automatically operable control valve.

3|. This regulator matic action and is appropriately attached to the disk like portion l3 of the body of the valve. It expansible and contractible and its activity can be regulated through the instrumentality of the springs 29 which are tenquire.

In practice, the fitting commonly used on suction line valves of present type refrigeration units (not shown) is removed and the nipple it of the improved safety valve H1 is attached to the part in Figure 1. The suction line 8 from the cooling coil (not shown) is connected to the nipple I5. A compound gage (not shown) connected to the regular fitting provided for the same, is then temporarily installed and the pressure control adjusting nuts 28 are adjusted up or down, as the case maybe, until the desired valve shut of! pressure is obtained. The heat laden vapor passes through the valve in a direction indicated by the arrows, but when the desired pressure on the outlet side i6 is reached, the valve closes. Obviously the valve closes as a result of pressure exerted within the bellows sylphon 3i causing the same to expand and raise the valve stem 22 to seat or close the valve head 25 against its seat l9. Moreover when the pressure within the bellows is reduced to a predetermined degree the sylphon contracts forcing the valve stem down and opening the valve automatically. Thus, the valve is in a sense an equalizing safety or differential control device. The valve remains closed until the operation of the piston reduces the crank case pressure below the closing point. No matter what pressure exists on the side l5, pressure on the side l6 can never exceed the amount set for, as immediately this the safety valve closes. With a zero pressure on the side it, the valve will remain open, ofiering no interference with normal operating conditions. Thus the valve is automatic in that it develops the desired differential or equalizing action on either side depending on normal and abnormal pressure conditions.

It has been found that a valve of this type when used in refrigerating systems eliminates leaks at the stufling box from excess pressure, overcomes the necessity of placing manual restrictions on units being put back in service. It reduces gas leaks and loss of refrigerant to a minimum, obviates the necessary of scrubbing oil in so-called warm jobs. It protects the flapper and piston valves against oil hammering, overcomes over loading of the condensing units, with the atto which the invention relates will be able to obtain a clear understanding of the invention after considering the description in connection with the drawings. Therefore, a more lengthy description is regarded as unnecessary.

Minor changes in shape, size, and rearrangement of details coming within the field of invention claimed may be resorted to in actual practice, if desired.

Having thus claim as new is:

In a refrigerating system, means for automatically closing the pipe line leading to the com-' pressor when crank case pressure in the compressor becomes excessive, comprising a valve casing located in the pipe an opening passing through its top and in communication with the low pressure side of the line,

. a valve seat formed in the casing and opening downwardly into the high pressure side of the casing for placing the opening in communication with the high pressure side, a one, piece valve stem passing through the first mentioned opening and through the valve seat, a valve having a threaded part threaded to the lower end of the stem and moving upwardly against the seat when moving to closed position, a bellows having its lower end connected with the top of the valve casingand surrounding the upper end of the opening and through the top of which the stem passes, means for connecting the top of the bellows with the stem, a cap-like member connected described my invention, what I the bellows and having a hole in its top through which the stem passes, a spring encircling a part of the stem and having one end bearing against the top of the bellows and its other end against the top of the cap-like member, a second spring encircling the outer part of the stem and having one end bearing against the top of the cap-like member and a nut threaded on the upper end of the stem and bearing against the top of the last mentioned spring.

FRANK SIMMONS.

line, said casing having with the top of the valve casing and enclosing installation without requiring changes

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