Pressure regulating valve

A pressure regulating and exhaust valve having an upstream port and a downstream port interconnected by a flow path. An adjustable pressure regulating valve is mounted in said flow path for regulating the downstream pressure in said flow path. The exhaust valve is a check valve that is mounted in parallel with said pressure regulating valve in said flow path for exhausting the downstream pressure from said downstream port to said upstream port.

TECHNICAL FIELD 
This invention relates generally to the valve art, and more particularly, 
to an improved air valve which comprises the functions of pressure 
regulating when air is flowing from an upstream port and through the valve 
in one direction to the downstream port, and free flow of air when air is 
flowing from the downstream port and through the valve in the other 
direction to the upstream port. The valve of the present invention is 
adapted for use in an air flow line to provide pressure regulation in the 
air flow line, as for example, an air supply line connected to one end of 
an air cylinder. 
BACKGROUND ART 
It is known in the air valve art to provide single or multiple pressure 
regulators to control the pressure of air supplied to an air cylinder or 
other device being controlled. Heretofore, multiple pressure regulators 
have been employed by mounting multiple directional valves in stacking 
fashion or on a common manifold base. However, such structure is expensive 
and awkward in use, and it is extremely difficult and expensive to provide 
pressure regulation to individual outlets. Because of the high cost, small 
space and relatively short life of diaphragms, and other components of 
pressure regulators, it is not common to use such multiple pressure 
regulators in a line between the outlet or cylinder port of a directional 
valve and a device being controlled as, for example, an air cylinder. Due 
to the complexity, space requirements and cost, it has not been practical 
heretofore to provide a pressure regulation means and free flow means 
between the cylinder port of a directional control valve and a device 
being controlled, such as an air valve. The result has been a waste of air 
requiring excessive pumping capacity, a waste of energy, and an increase 
in the cost of using air as a power and control means. Examples of the 
prior art regulating valves are illustrated in German Pat. No. 2,738,476 
and in U.S. Pat. Nos. 2,272,091; 2,501,483; 2,698,632; Re. 29,292; 
3,400,735; 3,621,867; 3,376,792; 3,747,629; 3,825,029, and 4,182,360. A 
further disadvantage of the prior art pressure regulating valves is that 
they do not provide a quick exhaust function for quickly and completely 
exhausting downstream pressure. 
DISCLOSURE OF THE INVENTION 
In accordance with the present invention, a combination pressure regulating 
and free flow valve is provided which can be installed in any line 
supplying air to an air operated apparatus, to regulate the pressure in 
one direction and provide a free flow of exhausting air in the other 
direction. The valve includes an adjustable pressure regulator valve which 
regulates the pressure of air supplied to an air supply line which is 
supplying air to an air operated apparatus. The valve includes a check 
valve which is operative when the air is flowing in said one direction, 
and which opens to exhaust air through said air supply line in the other 
direction when the supply air is removed from the valve. 
The pressure regulator valve includes a valve element which is mounted on a 
lower valve stem member for controlling the flow of fluid through a first 
passageway which connects an upstream port with a downstream port. The 
lower valve stem member is adjustable by a regulator spring and a movable 
upper valve stem member. A check valve is operatively mounted in parallel 
with the regulator valve in a second passageway and functions first as a 
check valve when the regulator valve is operative to regulate pressure, 
and then functions secondly to exhaust the downstream pressure through the 
second passageway in a free flow out condition. The regulator valve 
element is moved to the open position when the downstream pressure drops 
and adds to the exhaust capacity when the valve is exhausting downstream 
pressure. 
The valve structure for the valve of the present invention is simpler than 
the prior art regulating valve structures. The simpler valve structure 
results in lower tooling and manufacturing costs. The valve of the present 
invention is advantageous in that it provides, in one compact and 
economical unit, a pressure regulating valve and a free flow out valve.

BEST MODE OF CARRYING OUT THE INVENTION 
Referring now to the drawings, and in particular to FIGS. 1, 2 and 3, the 
numeral 10 generally designates an illustrative embodiment of a pressure 
regulating valve made in accordance with the principles of the present 
invention. The valve 10 includes a valve body 11 which is enclosed on the 
top side by a top end cover plate 12 which is releasably secured in 
position on the valve body 11 by a plurality of suitable machine screws 
13. A suitable bottom end cover plate 14 encloses the bottom end of the 
valve body 11, and it is releasably secured thereto by a plurality of 
suitable machine screws 16. A suitable gasket 15 is disposed between the 
bottom end cover plate 14 and the valve body 11. 
The valve body 11 is provided with a threaded supply or upstream port 19 
which is adapted to be connected by suitable conduit means to a suitable 
source of supply of pressurized air. The supply port 19 communicates with 
an upper or first interior passageway 20 which is centrally formed through 
the valve body 11. The upper interior passageway 20 communicates through a 
pair of longitudinally spaced apart bores or passageways 22 and 23 with a 
lower second interior passageway 24. The bores 22 and 23 are formed 
through a dividing wall 21 which is disposed between the passageways 20 
and 24. As viewed in FIG. 2, the left end of the passageway 24 has a 
portion 25 which communicates with a threaded downstream or cylinder port 
26, and a portion 27 which communicates with a threaded port 28 for the 
reception of a suitable gage, if desired, or a plug. The downstream port 
26 is adapted to be connected to an apparatus to be controlled as, for 
example, the head end of an air cylinder. 
As shown in FIG. 2, a pressure regulating valve, generally indicated by the 
numeral 30, is operatively mounted in the valve body 11 for controlling 
the flow of pressurized air entering the valve 10 through the supply port 
19 and passing through the upper interior passageway 20 and out through 
the bore 22 into the lower interior passageway 24, and thence out of the 
valve through the downstream port 26. The numeral 31 in FIG. 2 generally 
designates a check valve for completely exhausting the downstream 
pressure, when the downstream pressure builds up to a certain pressure and 
the regulator valve 30 closes. The exhausting air enters the valve 10 
through the downstream port 26 and flows through the lower interior 
passageway 24 and upwardly through the open bore 23 into the upper 
interior passageway 20 and out through the supply port 19 in a free flow 
manner. 
As shown in FIG. 2, the adjustable pressure regulator valve 30 includes an 
upper cylindrical valve stem, generally indicated by the numeral 32, which 
is provided with peripheral thread 33 on the lower end thereof. The 
threaded lower or inner end of the valve stem 32 is threadably mounted 
through a threaded bore 34 which is formed through the top end cover 12, 
and it is extended downwardly into an enlarged bore 36 which is formed 
vertically in the valve body 11. A peripheral, annular stop flange 37 is 
integrally formed on the lower or inner end of the valve stem 32, below 
the thread 33, and it is adapted to function as a stop member when the 
upper valve stem 32 is threaded outwardly or upwardly, so as to bring the 
stop flange 37 into an abutting engagement with the inner face of the 
cover plate 12 through which is formed the threaded bore 34. The outer 
periphery of the annular stop flange 37 is knurled. 
As shown in FIG. 2, the upper valve stem 32 is provided with an axial bore 
38 which extends upwardly from the lower inner end thereof, and in which 
is operatively seated the upper end of a pressure regulating coil spring 
46. The lower end of the regulating coil spring 46 extends downwardly 
through the bore 36 and into a reduced diameter communicating bore 42 in 
the valve body 11. A transverse shoulder 43 is formed at the junction 
point between the inner end of the bore 36 and the adjacent upper end of 
the bore 42. The lower end of the bore 42 communicates with the upper 
interior passageway 20. 
As shown in FIG. 2, the lower end of the regulating coil spring 46 abuts 
the upper, head end of a lower valve stem, generally indicated by the 
numeral 44. The lower valve stem 44 includes the head or piston 45 which 
is slidably mounted in the bore 42. The lower valve stem head end 45 is 
provided with a peripheral groove 47 in which is operatively mounted 
suitable seal means 48. The lower valve stem 44 further includes an 
elongated, cylindrical guide rod portion 49 which is integrally attached 
at its upper end to the lower side of the valve stem head end 45. The 
guide rod portion 49 extends downwardly across the upper interior 
passageway 20, and through the bore 22, and thence into the lower interior 
passageway 24. A regulating valve element, generally indicated by the 
numeral 50, is fixedly mounted on the lower end of the guide rod portion 
49, in the lower interior passageway 24, and it is movable between a 
raised or closed position, as shown in FIG. 4. 
The regulating valve element 50 includes an annular valve body 54 (FIG. 2) 
which has an annular valve element 58 molded thereon that has a conically 
shaped upper peripheral face. 
The valve element 58 may be made from any suitable elastomeric material 
which is molded onto the upper end of the annular valve body 54. 
The lower end of the bore 22 terminates at a sharp junction point with the 
upper wall surface of the lower interior passageway 24 to form a circular, 
sharp edged valve seat 62 against which the tapered or conically disposed 
valve element 58 is adapted to be operatively seated when the regulator 
valve element 50 is in the closed position shown in FIG. 2. The upper 
valve stem 32 is provided with a transverse slot 35 on the upper outer end 
for the reception of a suitable tool for adjusting the upper valve stem 
32. 
As shown in FIG. 2, the check valve 31 includes a T-shaped upper valve stem 
which is indicated by the numeral 66, and which comprises a cylindrical 
head portion 67 that is seated in a bore 68 which extends inwardly into 
the valve body 11 for the upper end thereof. The upper valve stem 66 
further includes an integral, reduced diameter, elongated cylindrical body 
portion 70 which is slidably mounted in a bore 69 that is of a diameter 
smaller than the bore 68. The bore 69 communicates at its upper end with 
the bore 68 and at its lower end with the upper interior passageway 20. 
The lower end of the upper valve stem head portion 67 is of a larger 
diameter than the bore 69, and a shoulder 73 is formed by the junction of 
the bores 68 and 69. An annular groove 71 is formed around the periphery 
of the lower end of the valve stem head portion 67, and a suitable O-ring 
seal 72 is operatively seated in said groove 71 and it sealingly engages 
the bore 68 and the shoulder 73. 
As shown in FIG. 2, a poppet valve element, generally indicated by the 
numeral 78, is operatively associated with the aforedescribed valve stem 
66, as described in detail hereinafter. The poppet valve element 78 
functions as a check valve, as explained more fully hereinafter. The 
poppet valve element 78 includes a conical nose portion 79 which has a 
downwardly converging peripheral side face 79a. The poppet valve element 
conical nose portion 79 is provided with a peripheral groove 85 around 
which is operatively mounted a suitable seal 86. In the closed position, 
the seal 86 is adapted to be seated on an inwardly tapered circular valve 
seat 87, which is formed at the upper end of the bore 23, and which has a 
sharp inner circular edge. 
As shown in FIG. 2, the poppet valve element 78 includes an elongated 
cylindrical movable valve stem 82 which has its lower end integrally 
attached to the conical nose portion 79. The valve stem 82 is slidably 
mounted in a cylindrical bore 77 which is formed in the lower end of the 
cylindrical body portion 70 of the upper valve stem 66. The numeral 81 
indicates the upper end wall of the bore 77 in the valve stem 66. A 
longitudinal bore 83 is formed in the upper end of the valve stem 82 and 
it extends downwardly from the upper end 80 of the stem 82. A suitable 
light, coil spring 84 has the lower end thereof mounted in the stem bore 
83 and the upper end is extended into the bore 77 and seated against the 
upper end wall 81 of the bore 77. The numeral 75 in FIG. 2 designates a 
vent hole for venting the stem bore 83 through the lower valve stem 82. 
The numeral 76 designates the lower end of the upper valve stem body 70. 
As shown in FIGS. 1 and 2, a locking screw means, generally indicated by 
the numeral 93 is operatively mounted in the upper end of the valve 10 for 
locking the upper valve stem 32 of the regulator valve 30 in an adjusted 
position. The locking means 93 comprises a screw 94 which is threadably 
mounted in the threaded bore 95 that is formed through the upper cover 
plate 12. The screw 94 has a cross slot 96 formed on the upper, outer end 
thereof for the reception of a suitable tool for rotating the screw 94. 
The screw 94 has a reduced diameter shaft 97 integrally attached to the 
inner end thereof. An inverted, conically shaped head 98 is integrally 
attached to the inner end of the shaft 97. 
The locking means 93 also includes a pair of slidable locking plates 91 and 
92 which are seated in a rectangular recess 90 that is formed in the upper 
end of the valve body 11, and which communicates with the bores 36 and 68. 
The locking plates 91 and 92 are spaced apart from each other and they 
each have a downwardly and outwardly sloping surface 99 formed on the 
upper end corner thereof for seating engagement with the conical head 98 
on the screw 94. The outer surfaces 100 and 101 of the locking plates 91 
and 92, respectively, are circularly formed in plan view for seating 
engagement against the outer curved periphery of the check valve outer 
stem head portion 67, and the circular flange 37 on the upper stem 32 of 
the regulator valve 30. It will be understood that when the screw 94 is 
turned inwardly, that the downward and inward movement of the conical head 
98 will cam the locking plates 91 and 92 laterally outward into a fixed 
locking engagement with the check valve upper stem head portion 67 and the 
flange 37 on the regulator valve upper valve stem 32 to hold the regulator 
valve upper valve stem 32 in an adjusted position. 
The valve of the present invention may be used in various air flow control 
applications for controlling the flow of air to and from an apparatus to 
be controlled and where a reduced downstream pressure is desired. An 
example is in the control of the flow of pressurized fluid to either end 
of an air cylinder, as to the head or piston end of an air cylinder for 
moving an air cylinder piston through a working stroke, and then 
exhausting the air in a free flow manner from the piston end of the 
cylinder to allow the piston to be returned to the starting position. 
In the aforedescribed use, FIG. 4 shows the valve 10 at rest, with no 
pressure at the supply port 19 or the downstream port 26. FIG. 4 also 
shows the valve 10 is a working condition when pressurized air is flowing 
into the inlet port 19 and through the valve 10 and out the downstream 
port 26. FIG. 2 shows the valve 10 in a condition wherein a predetermined 
downstream pressure is reached and the regulator valve 30 closes. The 
valve stem 32 of the pressure regulator valve 30 is threaded inwardly to 
provide the desired spring pressure on the lower valve stem 44, equivalent 
to a predetermined downstream pressure. 
When air under pressure is admitted from a suitable source into the supply 
port 19, the regulator valve element 50 is in the open or at rest position 
shown in FIG. 4 to allow air under pressure to pass from the upper 
interior passageway 20 down through the bore 22 into the lower interior 
passageway 24 and then out through the downstream port 26 to the head end 
of the cylinder to provide working air under pressure to the cylinder 
piston. The pressurized air in the upper interior passageway 20 functions 
to keep the check valve 78 in contact with valve seat 87 so that 
pressurized air can only flow from the upper interior passageway 20 to the 
lower passageway 24 through the bore 22. As the flow of pressurized air 
continues, pressure is built up downstream until it reaches an amount that 
is equivalent to the load applied by the regulating spring 46. The 
regulating valve 50 will then be moved upwardly to the closed position 
shown in FIG. 2, whereby the downstream pressure is reduced to a 
predetermined level. 
When line pressure is removed from the upstream port 19, to allow 
exhausting or dumping of the downstream pressure, the downstream pressure 
in the lower interior passageway 24 moves the poppet check valve 78 
upwardly in a quick action against the light spring 84. The downstream 
pressure moves the valve 78 upwardly to the raised position shown in FIG. 
6 to allow the downstream pressurized air to flow freely out into the 
upper interior passageway 20 and out through the inlet port 19. When the 
downstream pressure drops to a level less than the pressure exerted by the 
regulating spring 46, the regulator poppet valve 50 is moved downwardly to 
the at rest position shown in FIG. 4. When the downstream pressure is 
exhausted, the spring 84 moves the check valve 78 downwardly to the closed 
position shown in FIG. 1. 
It will be seen that the valve of the present invention provides a 
regulating function when air is flowing through the valve 10 in one 
direction, and a free flow exhaust function when air is exhausting through 
the valve 10 in the other direction, and that such functions are carried 
out on air flowing through a single flow path. The single flow path is 
formed by the upper interior passageway 20 and the lower interior 
passageway 24. The combination pressure regulating and exhaust valve of 
the present invention is simpler in construction, and smaller in overall 
configuration than the prior art valves providing such actions. 
Accordingly, the valve of the present invention is economical, compact, 
and can be manufactured with less complicated manufacturing procedures 
than heretofore possible. 
INDUSTRIAL APPLICABILITY 
The combination pressure regulating and exhaust valve of the present 
invention is adapted for use in industrial air use applications where a 
reduced downstream pressure is desired. For example only, valves of the 
present invention may be used for connection to the ends of an air 
cylinder for controlling the operation of an air cylinder in either one 
direction, or both directions. The air cylinder would be employed in 
various types of industrial machines.