US3834413A

US3834413A - Universal high pressure regulator

Info

Publication number: US3834413A
Application number: US00313685A
Authority: US
Inventors: F Peterson
Original assignee: Individual
Current assignee: Individual
Priority date: 1972-12-11
Filing date: 1972-12-11
Publication date: 1974-09-10
Anticipated expiration: 1991-09-10

Abstract

A universal high pressure air regulator which functions as a two stage constant running unloader and regulator when used in conjunction with a check valve, an excess air release and regulator where no check valve is employed, or a safety valve, accomplished through the action of a valve seal adjustably spring biased in a closed condition and responsive to a pressure actuated cylinder, so that at a predetermined pressure the cylinder causes sufficient pressure to be applied against the valve to just overcome the combined spring biasing means and air pressure acting upon the valve which is exposed to the compressor airstream, thus preventing full unloading and permitting a balanced condition wherein only the air being used is replaced, excess air being discharged, i.e., only the peak of the pressure pulse is used or goes into the tank; when air usage from the receiver is ended the air pressure on one side of the valve overcomes both the spring and air pressure on the other side of the valve at the air pulse low cycle, dumping all the air pressure in the line until receiver air is again used, at which time the valve closes starting the cycle again.

Description

United States Patent [191 Peterson UNIVERSAL HIGH PRESSURE REGULATOR [76] Inventor: Fred M. Peterson, 3233 Caddo Tr.,

Fort Worth, Tex. 76135 [22] Filed: Dec. 11, 1972 [21] Appl. No.: 313,685

Primary Examiner-Robert G. Nilson Attorney, Agent, or Firm-C. M. Woodward Sept. 10, 1974 [5 7] ABSTRACT A universal high pressure air regulator which functions as a two stage constant running unloader and regulator when used in conjunction with a check valve, an excess air release and regulator where no check valve is employed, or a safety valve, accomplished through the action of a valve seal adjustably spring biased in a closed condition and responsive to a pressure actuated cylinder, so that at a predetermined pressure the cylinder causes sufficient pressure to be applied against the valve to just overcome the combined spring biasing means and air pressure acting upon the valve which is exposed to the compressor airstream, thus preventing full unloading and permitting a balanced condition wherein only the air being used is replaced, excess air being discharged, i.e., only the peak of the pressure pulse is used or goes into the tank; when air usage from the receiver is ended the air pressure on one side of the valve overcomes both the spring and air pressure on the other side of the valve at the air pulse low cycle, dumping all the air pressure in the line until receiver air is again used, at which time the valve closes starting the cycle again.

2 Claims, 2 Drawing Figures PAIENTEBSEPIOW 3.834.413

- Wk m RECE/ VER COMPRESSOR BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates generally to air compressor regulators and more specifically to a two stage constant running regulator and unloader for the efficient operation thereof.

2. Description of the Prior Art When an air compressor powered by a gasoline engine, and in many instances by electric motors, needs to be run for or in continuous operation, some means is normally required for limiting the pressure in the tank or receiver to either that which the operation dictates and/or a pressure which is safe. This function is normally accomplished in the prior art by employment of intake valve unloaders which are generally operated by pilot valves. Such unloaders must, of necessity, be designed specifically for each type of compressorand matched to the particular compressor for which they will be employed, i.e., they operate satisfactorily only for the particular brand for which they. are designed. Additionally, such unloaders generally accomplish only the one unloading function and usually only within a range of psi. to p.s.i. differential. In addition, such valves are extremely sensitive to adjustment which must normally be accomplished by experts because of their extreme sensitivity, and are also very sensitive to any foreign matter such as dirt, carbon, oil, etc., usually encountered in such environments. A leak in such a valve terminates the pumping action of the compressor, rendering it incapable of further work until the valve is repaired.

Although the prior art has approached operation on the basic principle of the present invention, for example, as shown in prior art patents such as the hydraulic device of US. Pat. No. 1,779,640 issued to F. J. Rayfield in 1930 and other related devices, none have accomplished the objects or advantages of the present invention relative to simplicity, ease of maintenance, safety, or wide application to portable air compressors, nor would it be feasible to modify such devices to do so without major variations therefrom.

SUMMARY OF THE INVENTION It is the general object of this invention to provide an unloader and regulator for an air or gas compressor.

A more specific object of the invention is the provision of a two stage, constant running unloader and reg ulator which is economical to manufacture, easy to maintain, relatively immune to damage or failure from trash, may be adjusted readily by the operator, and may be employed without modification as an excess air release valve, an extremely sensitive safety valve and a regulator with little or no fading, yet one which is usable on any known compressor within its CFM rating and pressure range, the objects being accomplished through the provision of an adjustably biased valve opening into the device from the working pressure side whereby a pressure actuated reaction member on the working pressure side causes one of three conditions; a pulsing of the adjustably biased valve to maintain a balancing pressure within the system wherein only the peak of the pressure pulse is used, a closed valve condition for building pressure at a maximum efficiency, or

an open valve condition to cause pressure within the system to dump.

These and other objects of the invention and advantages thereof will be apparent to those skilled in the art from the following description of a preferred embodiment thereof taken in conjunction with the drawings, wherein;

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional side elevational view of a valve constructed in accordance with the present invention;

FIG. 2 is a schematic view of the valve of FIG. I used as a constant running regulator.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring first to FIG. 1, a two stage constant running unloader or regulator 10 in accordance with the present invention is shown as comprising an unloader body 12 having a passage 14 connecting

attachable ends

16, 18 leading to the compressor and receiver respectively (shown schematically), the receiver either connected through to a pressure tank to pressure chamber 20 of the regulator or directly to the pressure chamber 20 which is formed within valve operating cylinder 22, communication being through threaded pressure orifice 24. Operating cylinder 22 has a valve operating piston 26 slideably positioned therein, O-ring 28 assuring a gas seal between cylinder 22 and piston 26. Piston 26 carries valve piston rod 30 thereon extending through compressor exhaustchamber 32, the latter having exhaust ports 34 opening to atmosphere. An O-ring 36 may be employed to seal cylinder head 38 to cylinder 22, secured by cylinder head retaining bolts 40 threaded to retaining holes 42 in unloader body 12. Body 12 is provided with compressor air release port 44 having valve seat 46, piston rod 30 extended into release port 44 so as to contact ball valve 48 which normally closes off release port 44 from exhaust chamber Ball valve 48 is held in the sealed.(normal) operative position through pressure control compression spring 50 which is controlled through adjustable pressure spring piston 52 slideably positioned within pressure spring barrel 54, piston 52 and barrel 54 being held in sealing relationship by O-ring 56. Pressure spring piston 52 is positioned through adjustment screw 58 and lock nut 60. Pressure spring barrel 54 may be removably joined to unloader body 10 by conventional means such as threads 62, and sealed as by cap member 64.

In operation, when the compressor is started, the compressed air passes through unloader body 12 via conduit or passage 14, flowing freely around ball valve 48 which is held in the closed, pressure-building position by adjusting compression spring 50, and into the receiver or pressure tank of the system. The pressure build-up within the receiver obviously effectuates a like pressure in pressure chamber 20 of regulator 10, acting against the face of valve operating piston 26. The desired pressure is normally pre-set by adjustment of compression spring 50 through adjusting screw 58, although it will be apparent that this setting may be varied during operation a distinct advantage of the present invention which is incapable of accomplishment in conventional pilot valve operated unloaders and other prior art devices.

As the receiver pressure reaches the predetermined pressure setting, piston 26 acting through piston rod 30 exerts sufficient pressure on ball valve 48 to force it slightly away from its seat 46, but still just off its pressure-building sealed-relation position. When only slightly so raised, valve 48 is being acted upon by both pressure control compression spring 50 and the air pressure and flow within passage 14 of body 12. As valve 48 uncovers or unseats from valve seat 46, some of the compressed air in passage 14 enters compressor exhaust chamber 32 where it escapes to atmosphere through exhaust port 34. However, the combined compression spring-compressed air-aerodynamic pressure acting on the upper side of valve 48 keeps the unit from unloading fully, i.e., the valve 48 moves in and out with the pulse of the air compressor and holds a very closely regulated pressure on the receiver, the remainder of the unused air being exhausted through vent ports 34. This balancing condition is a most unique and important feature of the present invention, since it permits lower power consumption (thus lower fuel requirements) because of the even setting. The present regulator in this first stage of unloading holds a constant but low throttle setting analogous to cross-country driving and my experience has been that even when going from a no-load to full-load condition, the engine throttle never fully opens, the time element inherent in the design permitting the system to load and unload in time with the governed throttle setting. This is a distinct advantage over conventional pilot valve unloaders which are usually set on the low side of their differential pressure range so that they maintain several pounds pressure above the highest pressure that will be required by the compressor user, even though this high pressure may be necessary only a very few times over a given period. In addition, such conventional pilot valve unloaders continually cycle from wide open to no-load, a condition which is manifestly hard on the engine and the compressor.

Another major advantage of the invented device are the lower temperatures achieved in both the air lines and the receiver, since not only is there no reason to pump at a higher pressure than is being employed, but because the excess air is not put into the tank, i.e., all of the BTUs produced by the compressor in a given time are not required to be dissipated through radiation, etc., but are bled-off with the vented portion of the pulse. Since only the peak of-the pressure pulse goes into the receiver, the line pressure fluctuates up and down with the compressor piston and therefore exerts less resistance to the compressor and engine. In my experience to date, and depending of course on air usage, the engine load in this regulating or first unloading stage is from about 60 to 90 percent of the engine full load. This condition pertains in the system of FIGS. 1 and 2, i.e., with or without a check valve in the system.

After air usage from the receiver is stopped, the pressure in the receiver is very slightly increased, thus increasing pressure within chamber of the unloader, pressure on the valve operating piston 26 overcomes the combined seating force of pressure control spring 50 and air pressure acting on valve 48 at the air pulse low cycle, rod 30 opening valve 46-48 rapidly, thus dumping all of the air pressure in the line between the check valve (if present as in FIG. 1) and the compressor. At this point in the cycle, compressor and engine are under about a 5 percent load. Without a check valve in the system. as shown in FIG. 2, the device of the present invention operates as an excess air release and regulator. As long as this pressure remains in the receiver, the air will continue to be dumped through air release port 44 and exhaust ports 34 via exhaust chamber 32.

On further use of air from the receiver, the pressure obviously drops in chamber 20, permitting adjusting compression spring 50 to reseat valve 48 and depress piston 26 through rod 30, thus starting the cycle over again. Although the differential pressure in a device constructed in accordance with the present invention is approximately 10 to 15 pounds from fully loaded to unloaded, as soon as it reaches the first stage of unloading, fading is normally less than 2 pounds.

Additional advantages of the present invention include the almost total absence of continuous maintenance and tine tuning, and relatively non-critical manufacturing tolerances. For example, the only wearing parts that can normally create problems are theO-

rings

28, 56, which can be purchased for replacement at any auto supply store, and installed by any normally adept mechanic. Even then, a leak past the O-ring 56 between the pressure spring barrel and piston will not affect the operation even though it will obviously cause loss of air between the compressor and receiver. A bad or gross leak past the O-ring 28 between the valve operating piston 26 and operating cylinder 22 will only let enough air into and out of the receiver to prevent the unit from accomplishing its second stage of unloading, i.e., all the air pressure between the compressor and check valve will not be dumped but the system will continue to run in its first or regulating-balancing stage. A leak past the ball valve 48-seat 46 through air release port 44, such as may be caused temporarily by dirt, carbon, trash, water, etc., will not affect the control or operation so long as the compressor itself is not too small to handle the load. In fact, as above noted, air release port 44 is normally slightly open during operation anyway.

The present device also automatically fully unloads the compressor when the engine stops or stalls if the receiver has as much as 50 percent of the working pressure setting, thus making it possible to start again without draining air from the receiver.

As will be apparent to those skilled in the art, the device of the invention may be used without a check valve as a highly efficient regulator, and will do everything but the final unloading which, in many instances, is desirable. in this instance, it is merely installed near the receiver in the line from the compressor without a check valve, or the check valve may be by-passed when desired. Likewise, mounted on a receiver it will function as an extremely sensitive safety valve having a large discharge capacity and low bleed-down range. Due to the construction, as noted, it is not apt to freeze up due to corrosion as are most conventional safety valves, while the opening" pressure on the valve is multiplied by the valve piston so that, even if it becomes stuck, the pressure range required to free "it is less because of the multiplying factor.

It is apparent also that a check valve may be incorporated with the regulator unit by incorporating the line from the receiver to the pressure chamber in the body of the unit on the outside of the check valve.

Having now described the preferred embodiment of my invention, I claim:

1. In a compressor system including an air compressor, and a receiver, the improvement which comprises:

a regulating device interposed between the compressor and a receiver comprising 1. a substantially unimpeded conduit having closeable direct communication with pressure release means,

2. said pressure release means comprising a cylinder opening on one end to atmosphere and on the other end to said receiver, a ball valve closing the communication between said conduit and said cylinder, pressure responsive piston means operatively associated with said ball valve and slideably interposed within said cylinder between said one end opening to atmosphere and said other end opening to said receiver, and selective biasing means operatively associated with said ball valve,

whereby while receiver pressure is below the pre-set value all compressor generated pressure builds in said receiver, when said receiver pressure reaches the pre-set value said piston slightly opens communication between said conduit and said receiver by acting against said ball valve and said ball valve biasing means thus moving said ball means more directly into said conduit and thus into the compressed air stream, the airstream flow in said conduit thus reacting against more of the exposed surface of said ball valve and operative to just overcome said piston movement by the air stream flow reaction thereon and thereby closing communication between said conduit and said receiver intermittently to derive a balancing condition in said system so that only the peak of the pressure pulse goes into the receiver, the remainder being exhausted through said exhaust chamber.

2. In the system defined by claim 1, the addition of:

check valve means interposed between said regulating device and said receiver whereby on reaching the pre-set pressure value said piston overcomes both said selective biasing means and the air flow pressure on the low cycle of the compressor air pulse to thus permit substantially gross movement of said piston and said ball valve operative to dump through said exhaust chamber substantially all the air pressure within the system between said compressor and said check valve.

Claims

1. In a compressor system including an air compressor, and a receiver, the improvement which comprises: a regulating device interposed between the compressor and a receiver comprising 1. a substantially unimpeded conduit having closeable direct communication with pressure release means, 2. said pressure release means comprising a cylinder opening on one end to atmosphere and on the other end to said receiver, a ball valve closing the communication between said conduit and said cylinder, pressure responsive piston means operatively associated with said ball valve and slideably interposed within said cylinder between said one end opening to atmosphere and said otheR end opening to said receiver, and selective biasing means operatively associated with said ball valve, whereby while receiver pressure is below the pre-set value all compressor generated pressure builds in said receiver, when said receiver pressure reaches the pre-set value said piston slightly opens communication between said conduit and said receiver by acting against said ball valve and said ball valve biasing means thus moving said ball means more directly into said conduit and thus into the compressed air stream, the airstream flow in said conduit thus reacting against more of the exposed surface of said ball valve and operative to just overcome said piston movement by the air stream flow reaction thereon and thereby closing communication between said conduit and said receiver intermittently to derive a balancing condition in said system so that only the peak of the pressure pulse goes into the receiver, the remainder being exhausted through said exhaust chamber.

2. said pressure release means comprising a cylinder opening on one end to atmosphere and on the other end to said receiver, a ball valve closing the communication between said conduit and said cylinder, pressure responsive piston means operatively associated with said ball valve and slideably interposed within said cylinder between said one end opening to atmosphere and said otheR end opening to said receiver, and selective biasing means operatively associated with said ball valve, whereby while receiver pressure is below the pre-set value all compressor generated pressure builds in said receiver, when said receiver pressure reaches the pre-set value said piston slightly opens communication between said conduit and said receiver by acting against said ball valve and said ball valve biasing means thus moving said ball means more directly into said conduit and thus into the compressed air stream, the airstream flow in said conduit thus reacting against more of the exposed surface of said ball valve and operative to just overcome said piston movement by the air stream flow reaction thereon and thereby closing communication between said conduit and said receiver intermittently to derive a balancing condition in said system so that only the peak of the pressure pulse goes into the receiver, the remainder being exhausted through said exhaust chamber.

2. In the system defined by claim 1, the addition of: check valve means interposed between said regulating device and said receiver whereby on reaching the pre-set pressure value said piston overcomes both said selective biasing means and the air flow pressure on the low cycle of the compressor air pulse to thus permit substantially gross movement of said piston and said ball valve operative to dump through said exhaust chamber substantially all the air pressure within the system between said compressor and said check valve.