Directional control poppet valve

A valve system for controlling the direction of flow of pressurized fluid. The valve system includes a valve housing, with an inlet port for receiving pressurized fluid therein, a first cylinder port and a second cylinder port. The housing is further constructed with first and second exhaust ports. Passageways connect the inlet port to the first cylinder port and to the second cylinder port. Passageways also extend from the first cylinder port to the first exhaust port and from the second cylinder port to the second exhaust port. A pair of pistons and corresponding poppet valves are slidable within the housing to control flow of fluid through the passageways. In one embodiment, the pistons and poppet valves are moved by communicating fluid pressure from the inlet port either above or below the pistons. In an alternative embodiment, the pistons and popper valves are mechanically actuated.

BACKGROUND OF THE INVENTION 
This invention relates to directional valves and more particularly to a 
four-way, three-position poppet valve. 
It is advantageous in many fluid control systems to have a directional 
valve structure having four selectable flow paths to control fluid flow 
from a pressure source to the apparatus being activated by the fluid. 
These "four-way" valves have heretofore been of several general types. The 
spool valve type generally includes a housing having an elongated bore 
with lateral inlet, outlet and exhaust ports communicating from the 
exterior of the housing to the bore area. A shaft is axially movable 
within the bore, and cylindrical enlargements or bosses on the shaft 
overlay various ports in different longitudinal positions to control the 
fluid flow from the inlet port to the outlet and exhaust ports and from 
the outlet ports to the exhaust ports. To prevent leakage between the 
shaft and the bore walls, these bosses are often provided with seals such 
as O-rings, which slidably engage the wall of the bore. These seals tend 
to wear rapidly as they must pass over the edges of the ports during the 
operation of the unit. 
Another general type of four-way valve system includes a housing having an 
elongated bore therethrough with ports extending between the side wall of 
the housing. In contrast to the first type, this type of valve has valve 
seats extending radially inward from the walls of the bore between the 
ports, and the movable shaft within the bore is provided with poppet heads 
fixed on the shaft and arranged to engage selected valve seats as it is 
moved longitudinally within the bore. As the poppet heads move on a single 
shaft, to properly seal the fluid channels formed by the poppet heads 
against the valve seats, the seals of at least two poppet heads must 
engage two valve seats at the same time. Therefore, the two poppet heads 
must be exactly the same distance apart as their two respective valve 
seats. The required accuracy is so great that normal manufacturing 
tolerances are unacceptable, and the cost of making such valves is 
undesirably high. To overcome this difficulty, valves have been provided 
having movable valve seats in order to permit simultaneous sealing of 
poppet heads against valve seats as required. However, these valve systems 
require additional complex movable parts and additional seals which add to 
the cost and complexity of the unit. 
Additionally, in this latter type of poppet valve structure, the prior art 
units have generally provided only two positions, that is fluid flow 
through two paths or fluid flow through the two alternative paths. Thus, 
in many of the prior art units, no center or neutral position, that is 
where all ports are either blocked or open, is provided. 
SUMMARY OF THE INVENTION 
The present invention provides a four-way, three-position poppet 
directional valve which overcomes many of the disadvantages of the prior 
art units. The present invention provides for selecting four fluid paths 
whereby input pressure may be communicated from an inlet port to a first 
cylinder port while a second cylinder port is communicated to its 
respective exhaust port. In the second position, fluid pressure is 
communicated to the second cylinder port with the first cylinder port 
communicating with its respective exhaust port. In the third position, all 
the ports are open or all ports are closed as desired by the particular 
design of the valve. This valving structure is accomplished without the 
disadvantages of the spool valves heretofore used and without the 
dimensional tolerances heretofore experienced with present poppet valves. 
In accordance with one embodiment of the invention, a valve system for 
controlling the direction of flow of pressurized fluid to opposite ends of 
the cylinder of a servo motor to actuate the piston of the servo motor in 
opposite directions is disclosed. The valve system includes a valve 
housing, with an inlet port for receiving pressurized fluid therein. A 
first cylinder port is provided in the housing and communicates with one 
end of the cylinder of the servo motor. The housing has a second cylinder 
port which communicates with the opposite end of the servo motor. The 
housing is further adapted with first and second exhaust ports. A first 
passageway extends from the inlet port to the first cylinder port and a 
second passageway extends from the inlet port to the second cylinder port. 
A third passageway extends from the first cylinder port to the first 
exhaust port, and a fourth passageway extends from the second cylinder 
port to the second exhaust port. 
A first poppet valve is slidable within the housing and is normally seated 
against a valve seat in the housing to close the first passageway. 
Similarly, a second poppet valve slidably received within the housing is 
normally seated against a valve seat within the housing to close the 
second passageway. A first piston slides within the valve housing and 
normally engages the first poppet valve to close the third passageway. A 
second piston is slidable within the valve housing and normally engages 
the second poppet valve to close the fourth passageway. Structure is 
provided for moving the first and second piston to selectively open and 
close the various passageways thereby controlling the flow of fluid 
through the valve system. 
In accordance with a more specific aspect of the invention, the movement of 
the pistons is provided by communicating the fluid pressure from the inlet 
port either above or below the piston heads. When fluid pressure is 
communicated above the piston heads, the pistons are moved against the 
poppet valve to unseat the poppet valve from the valve seat formed by the 
housing. This in turn opens the passageway from the inlet port to one of 
the cylinder ports. By communicating fluid pressure beneath the head of 
one of the pistons, the piston is unseated from engagement with the poppet 
valve thereby opening one of the passageways from one of the cylinder 
ports to its corresponding exhaust port. 
In accordance with another aspect of the invention, a first flow passage 
extends from the inlet port to an upper chamber above the first piston and 
to a lower chamber below the second piston. A valve for normally closing 
the first flow passage is provided. Thus, by opening and closing the 
valve, fluid pressure from the inlet port is communicated through the 
first flow passage to depress the first piston thereby opening the 
passageway between the inlet port and the first cylinder port while 
simultaneously raising the second piston to open the passageway between 
the second cylinder port and its corresponding exhaust port. A similar 
flow passage exists from the inlet port to an upper chamber above the 
second piston and to a lower chamber below the first piston and is 
similarly controlled by a valve to selectively communicate fluid pressure 
below the first piston and above the second piston to simultaneously open 
the passageway from the inlet port to the second cylinder port and the 
passageway between the first cylinder port and its respective exhaust 
port. Thus, fluid pressure is controlled between the inlet port and one of 
the cylinder ports and between the cylinder ports and their respective 
exhaust ports. 
In accordance with another aspect of the invention, the pistons are 
controlled manually by activation of a lever which engages the pistons and 
permits the translation of the pistons in opposite directions.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
FIG. 1 illustrates in schematic view a valve assembly indicated generally 
by the numeral 20 connected to a servo motor 22 for operation of the 
motor. Servo motor 22 includes a cylinder housing 24 having a piston 26 
slidable therein and a piston rod 28 adapted for movement with piston 26. 
Piston rod 28 is connected at its end opposite piston 26 to any chosen 
device which the valve assembly 20 is to operate. Piston 26 divides the 
cylinder chamber formed within cylinder housing 24 into an upper chamber 
30 and a lower chamber 32. A conduit 40 delivers pressurized fluid from a 
fluid pressure source 42 supplied by reservoir 43 to an inlet port 44 of 
valve assembly 20. Cylinder ports 46 and 48 of valve assembly 20 are 
connected by conduits 50 and 52, respectively, to communicate with 
chambers 30 and 32, respectively, of servo motor 22. Exhaust lines 68 and 
70 extend from exhaust ports 72 and 74, respectively, and are connected at 
their opposite ends to reservoir 43. Where the fluid is air, lines 68 and 
70 will exhaust to the atmosphere. In this case, reservoir 43 is 
eliminated. 
Electrical leads 75 and 76 extend from an electrical power source (not 
shown) to solenoids 77 and 78, respectively, within valve assembly 20. 
Handle assembly 80 is attached to the lower portion of valve assembly 20 
and may be used as a manual override to control the valve system. 
As will be discussed in greater detail hereinafter, when solenoid 78 of 
valve assembly 20 is actuated, pressurized fluid is communicated from 
conduit 40 through valve assembly 20 exiting from port 48 and through 
conduit 52 to chamber 32 of servo motor 22. Simultaneously therewith, 
fluid flows from chamber 30 through conduit 50 into valve assembly 20 and 
through exhaust line 68 to fluid pressure source reservoir 43. Again, 
where the fluid is air, it is normally exhausted to the atmosphere. 
Thus, when solenoid 78 is actuated, valve assembly 20 operates to activate 
servo motor 22 such that piston 26 and piston rod 28 move upwardly as 
illustrated by arrow 82 in FIG. 1. 
When solenoid 77 is actuated, pressurized fluid flows from conduit 40 into 
valve assembly 20 and from port 46 through conduit 50 into chamber 30 of 
servo motor 22. Simultaneously therewith, fluid from chamber 32 of servo 
motor 22 flows through conduit 52 into port 48 of valve assembly 20 and is 
discharged from exhaust port 74 through exhaust line 70 into the fluid 
reservoir 43 or to the atmosphere. Thus, by actuating solenoid 77, piston 
26 and piston rod 28 are moved downwardly in servo motor 22 in the reverse 
direction of arrow 82 of FIG. 1. 
The valve assembly is equipped with a manual override activated by handle 
80. By pivoting handle 80 counterclockwise in the direction of arrow 84 of 
FIG. 1 about axis shaft 86, fluid pressure from fluid source 42 flows 
through valve assembly 20 and out of port 48 into chamber 32 of servo 
motor 22. Simultaneously therewith, fluid flows from chamber 30 through 
conduit 50 into port 46 to be exhausted from port 72 through line 68 to 
hydraulic fluid reservoir 43 or to the atmosphere. Thus, piston 26 and 
piston rod 28 are made to move upwardly in the direction of arrow 82. 
Similarly, by rotating handle 80 clockwise in the reverse direction of 
arrow 84 of FIG. 1, fluid pressure from source 42 flows through conduit 40 
into valve assembly 20 and from port 46 through conduit 50 to chamber 30 
of servo motor 22. At the same time, fluid flows from chamber 32 through 
conduit 52 into port 48 of valve assembly 20 and is discharged through 
port 74 and line 70 to hydraulic fluid reservoir source 43 or exhausted to 
the atmosphere. 
When neither solenoid 77 or 78 is actuated and with handle 80 in the 
neutral position, fluid flowing from source 42 through conduit 40 is 
blocked within valve assembly 20 and no fluid passes into or out of ports 
46 or 48 or from exhaust ports 72 and 74. 
FIG. 2 illustrates a vertical section view of valve assembly 20 with the 
valve in a centered or third position. Valve assembly 20 includes a 
housing 100 with a lower housing 100a and an upper housing 100b suitably 
attached with a gasket 101 therebetween. Upper housing 100b, while 
actually constructed in three sections with gaskets fitted therebetween to 
facilitate forming passages therein, will be referred to as a single 
composite unit. Lower housing 100a has two parallel elongated bores 102 
and 104 extending substantially the full length of the body and each 
having its upper end closed by upper housing 100b and a lower end closed 
by plate 108 attached to housing 100. The ports previously mentioned all 
communicate laterally with bores 102 and 104. These ports comprise 
cylinder ports 46 and 48 and exhaust ports 72 and 74. Fluid power inlet 
port 44 communicates through housing 100 into bore 104 and includes a 
connecting chamber 110 connecting bores 102 and 104. 
Bores 102 and 104 are composed of varying sizes of concentric bores to 
accommodate a pair of pistons 120 and 122, respectively. Poppet valves 124 
and 126 are slidably engaged within poppet guides 128 and 130, 
respectively. Pistons 120 and 122 consist of a constant diameter shaft 
120a and 122a, respectively, with a larger diameter cylindrical head 120b 
and 122b, respectively. 
The lower circumferential edge of shaft portions 120a and 122a of pistons 
120 and 122 are formed with a knife edge 140 and 142 for sealingly 
engaging poppet valves 124 and 126 as will hereinafter be discussed in 
greater detail. 
Poppet valves 124 and 126 are formed as cylinder members having 
longitudinal bores 144 and 146 extending longitudinally therethrough. The 
upper portions of poppet valves 124 and 126 are formed with flanges 148 
and 150 to receive elastomeric circular seals 152 and 154, respectively. 
Poppet guides 128 and 130 are cylindrical members having lower flanges 160 
and 162 for engaging lower housing 100a. Guides 128 and 130 are each 
adapted with annular rib protrusions 164 and 166, respectively, which 
receive an elastomeric seal 168, such an O-ring, to form a seal between 
protrusions 164 and 166 and bores 102 and 104. 
Poppet guides 128 and 130 have cylindrical concentric bores 172 and 174 
extending longitudinally therethrough, respectively. Poppet valves 124 and 
126 have an outside diameter substantially equivalent to the diameter of 
the inner bores 172 and 174 of guides 128 and 130 and are received for 
slidable engagement within guides 128 and 130, respectively. Poppet valves 
124 and 126 are each provided with annular grooves for receiving 
elastomeric seals 176 to form a sealing engagement between the outer wall 
of the poppet valves and the inner wall of the guides 128 and 130. 
Guides 128 and 130 are provided with lateral bores 180 and 182, 
respectively, for communicating between exhaust ports 72 and 74, and inner 
bores 170 and 172 of guides 128 and 130. 
Referring now to bore 102 which receives piston 120 and poppet valve 124, 
bore 102 includes concentric bores 192, 194, 196 and 198. Bore 192 is 
sized to receive cylindrical head 120b of piston 120. Piston head 120b has 
an annular groove therearound for receiving an elastomeric seal 200, such 
as an O-ring, for forming a seal between head 120b and bore 192 of 
longitudinal bore 102. Bore 194 is sized to receive shaft 120a of piston 
120. Shaft 120a has an annular groove therearound for receiving an 
elastomeric seal 201, such as an O-ring, for forming a seal relationship 
between shaft 120a and bore 194 of longitudinal bore 102. An upper chamber 
202 is formed between head 120b of piston 120 and upper housing 100b. 
Likewise, a lower annular chamber 203 is formed beneath head 120b of 
piston 120 between seals 200 and 201. Bore 196 is larger than bore 194 and 
the outer diameter of shaft 120a of piston 120 and therefore defines an 
annular chamber 206 about shaft 120a. Annular chamber 206 communicates 
with cylinder port 46. 
Bore 198 is sized to slidably receive poppet guide 128 and annular 
protrusion 164 extending thereabout. Seal 168, retained within annular 
protrusion 164, forms a sealing relationship between casing member 128 and 
bore 198 of longitudinal bore 102. Bore 198 is larger in diameter than the 
diameter of seal 152 mounted on poppet valve 124 such that fluid may pass 
between seal 152 and bore 198. 
A circular seat 210 is formed at the point of transition between bore 196 
and bore 198 by upwardly chamfering bore 198 at this transition point. 
Seat 210 serves to facilitate forming a positive seal between the housing 
and poppet valve 124 as will hereinafter be discussed in greater detail. 
Guide 128 is maintained in a fixed relationship with respect to housing 
100a by engaging flanges 160 thereon within a recess formed with housing 
100a. Poppet valve 124 is slidably engaged with guide 128 and is biased 
upwardly by spring 220. Piston 120 is slidably recived within bores 192 
and 194 of longitudinal bore 102 and is biased downwardly by a spring 222 
acting between upper housing 100b and a recessed bore 224 within the head 
of piston 120. 
Spring 220 is sufficiently stronger than spring 222 such that poppet valve 
124 is normally urged upwardly and seals circular seal 152 against seat 
210. Piston 120 is urged downwardly by spring 222 and sealingly engages 
edge 140 against the upper side of seal 152 of poppet valve 124. However, 
spring 220 is sufficiently stronger than spring 222 to prevent the 
engagement of piston 120 against seal 152 of poppet valve 124 from 
disengaging the seal of 152 against seat 210 formed in housing 100a. 
Similarly, bore 104 includes a plurality of concentric bores corresponding 
to those of bore 102 for receiving piston 122, poppet valve 126 and guide 
130. As discussed with respect to bore 102 and piston 120, piston head 
122b of piston 122 has an elastomeric seal 230 therearound for forming a 
fluid-tight seal between head 122b and bore 104. This seal forms a 
fluid-tight chamber 232 between the top of piston 122 and the lower wall 
of upper housing 100b. Shaft 122a of piston 122 likewise has an annular 
groove therearound for receiving an elastomeric seal 234 which forms a 
fluid-tight engagement with bore 104. This seal forms a fluid-tight 
annular chamber 236 below head 122b. As described earlier with respect to 
piston 120, piston 122 is adapted with a knife edge 142 about the lower 
edge of shaft 122a for engaging seal 154 on poppet valve 150. Likewise, an 
annular chamber 240 is formed between shaft 122a and bore 104 which 
communicates with port 48. A seat 242 extends radially inwardly as bore 
104 is enlarged near the lower portion thereof, to sealingly engage seal 
154 of poppet valve 126. Poppet guide 130 is fixedly positioned with 
respect to housing 100 by the engagement of flange 162 within an annular 
indention within the housing. As previously described, guide 130 has a 
raised protrusion 166 for receiving an elastomeric seal 168 for engagement 
with bore 104, and is adapted with a lateral aperture 182 communicating 
between port 74 and the inner bore 174 of guide 130. 
As discussed with respect to piston 120 and poppet valve 124, a spring 260 
is positioned between the lower plate 108 forming the lower end of bore 
104 and poppet valve 126 to urge valve 126 upwardly such that a seal is 
normally formed between seal 154 and circular valve seat 242. A spring 262 
is positioned between the lower wall of upper housing 100b and piston 122 
to normally urge piston 122 downwardly to form a seal between lower edge 
142 of piston 122 and seal 154 of poppet valve 126. Spring 262 rests 
within a bore indention 264 which assists in positioning the spring 
relative to piston 122. While spring 262 exerts a downward force on poppet 
valve 126, spring 260 is sufficiently stronger than spring 262 such that 
the seal between the circular seat 242 formed in housing 100 and seal 154 
of poppet valve 126 is not broken by the action of spring 262. 
Referring still to FIG. 2, additional fluid channeling is provided within 
valve assembly 20 in order to properly actuate pistons 120 and 122 and 
poppet valves 124 and 126 in accordance with the present invention. 
Specifically these fluid passages include a vertical passage 280 extending 
upwardly and communicating with chamber 110. Passage 280 communicates at 
its upper end with a passage 282 which in turn communicates at each end 
thereof with vertical passages 284 and 286. The upper end of passages 284 
and 286 are adapted with valves 288 and 290, respectively. Solenoids 77 
and 78 are mounted immediately above valves 288 and 290 and solenoid 
shafts 77a and 78a are biased against valves 288 and 290, respectively, to 
normally close the valves thereby preventing the flow of fluid 
therethrough. Shafts 77a and 78a act within sleeve members 300 and 302, 
respectively. A fluid channel 304 communicates through sleeve 300 and 
extends downwardly therefrom. 
Referring to FIGS. 2 and 4, it may be seen that fluid channel 304 
communicates with chamber 202 formed above head 120b of piston 120 and 
upper housing 100b through part 202a (FIG. 4). Referring to FIGS. 2, 3 and 
4, it may be seen that fluid channel 304 communicates at its lower end 
with horizontal fluid channel 306. In turn, horizontal channel 306 
communicates with vertical channel 308 which extends upwardly from channel 
306 to communicate with annular chamber 236 formed below head 122b of 
piston 122. Horizontal channel 306 is plugged at its end remote from its 
junction with vertical channel 304. Thus, fluid passing through valve 288 
is communicated by way of channels 304, 306 and 308 with the chamber above 
piston 120 and below the head 122b of piston 122. 
Although not seen in FIG. 2, an identical channeling arrangement exists to 
communicate fluid flowing through valve 290 with chamber 232 above piston 
122 and by way of channels 320 and 322 shown in FIG. 4, to annular chamber 
203 below the head 120b of piston 120. 
The operation of the unit is shown by the illustrations of FIGS. 2, 5 and 6 
wherein FIG. 2 shows the valve at a neutral position, FIG. 5 shows the 
valve in the first limit position and FIG. 6 shows the valve in the second 
limit position. Referring first to FIG. 5, the operation of the valve is 
as follows. Fluid pressure is supplied at inlet port 44 and is 
communicated through bore 104 to chamber 110 and along the path of arrow 
330 through passages 280 and 282 and passage 284 to valve 288. Fluid 
pressure is normally sealed at valve 288 by solenoid shaft 77a of solenoid 
77. In order to actuate the valve to the first limit position, solenoid 77 
is actuated such that solenoid shaft 77a is retracted upwardly to unseat 
valve 288. 
With retraction of shaft 77a of solenoid 77, pressurized fluid is free to 
flow through valve 288 and into fluid channels 304 to communicate with 
chamber 202 above head 120b of piston 120. Fluid pressure existing in this 
fluid-tight chamber exerts a downward force on piston 120 sufficient to 
overcome the spring force of spring 220 acting through poppet valve 124 on 
piston 120 and unseated seal 152 of poppet valve 124 from circular valve 
seat 210 of housing 100a. 
With the unseating of seal 152 from circular seat 210 fluid pressure 
entering at inlet post 44 communicates through chamber 110 following the 
path of arrow 332 and passes through annular chamber 206 which 
communicates with port 46. Thus, port 44 is connected with port 46. 
Fluid pressure further communicates through fluid channel 304, channel 306 
and vertical channel 308 to communicate with annular chamber 236 below 
head 122b of piston 122. Thus, simultaneously with the downward force 
applied to piston 120, fluid pressure within fluid-tight chamber 236 
exerts an upward force on piston 122 to raise the piston against the 
action of spring 262. As piston 122 rises in bore 104, fluid at port 48 
follows the route indicated by arrows 338 communicating by way of annular 
chamber 240 through bore 146 of poppet valve 126 through bore 174 of 
poppet guide 130 and thereafter through lateral bore 182 to exhaust port 
74. Thus, port 48 is connected with exhaust port 74 to permit the flow of 
fluid through valve assembly 20 to exhaust port 74. 
Referring to FIG. 6, the reverse or second limit position is illustrated. 
In this position, fluid pressure entering inlet port 44 is communicated to 
port 48 and exhaust fluid entering port 46 is communicated to exhaust port 
72. This valve connection is accomplished by the retraction of solenoid 
shaft 78a of solenoid 78 to permit the communication of fluid from inlet 
port 44 through chamber 110, passages 280, 282, 286 and valve 290 to be 
communicated in a similar manner as described with respect to FIG. 5 to 
chamber 236 above piston 122 and annular chamber 203 below head 120b of 
piston 120 to simultaneously force piston 122 downwardly to unseat seal 
154 from circular valve seat 242 by compressing spring 260 and forcing 
piston 120 upwardly to unseat piston 120 from seal 152 of poppet valve 
124. In the configuration illustrated in FIG. 6, fluid pressure following 
the path of the arrow generally indicated by the numeral 250 flows through 
inlet port 44 into annular chamber 240 past the seal 154 and poppet valve 
126 to exit from port 48. 
Simultaneously therewith, exhaust fluid entering port 46 and following the 
arrow generally indicated by the numeral 252 passes from port 46 into 
annular chamber 206 through bore 144 of poppet valve 124 and bore 172 of 
poppet guide 128 through lateral bore 180 to exhaust port 72. Fluid 
pressure will continue to flow along these valve channels as long as fluid 
pressure is input to inlet port 44 and solenoid 78 is energized to unseat 
shaft 78a from valve 290. By simply de-energizing solenoid 78, shaft 78a 
is reseated over valve 290 and springs 260 and 220 and springs 262 and 222 
reposition pistons 122 and 120 and poppet valves 126 and 124 to the 
position illustrated in FIG. 2. In this position, inlet fluid pressure 
entering inlet port 44 is prevented from communicating either with port 46 
or port 48 by the seal created between seals 152 and 154 of poppet valves 
124 and 126 against circular valve seats 210 and 242 of housing 100a. 
Additionally, fluid pressure from port 46 is prevented from communicating 
with exit port 72 and fluid pressure from port 48 is prevented from 
communicating with exit port 74 by the seal formed between seal 152 and 
seal 154 and the lower edge of pistons 120 and 122, respectively. 
While the primary actuation means for valve assembly 20 are solenoids 77 
and 78, the valve assembly may also be actuated manually. As is shown in 
FIGS. 2, 5 and 6, a handle assembly 360 is attached to the lower face of 
valve assembly 20 through which the valve assembly may be manually 
operated. Handle assembly 360 includes a lever arm 362 rotatably pinned by 
axis shaft 364 to hub assembly 366 attached to the lower face of valve 
assembly 20. Hub assembly 366 includes a shaft 368 threaded on each end 
with one end engagable into a mating threaded bore in the valve assembly 
housing 100. The opposite end is threadedly engaged to a hub 370 which 
receives axis shaft 364. Threaded shaft 368 permits adjustment of lever 
arm 362 relative to valve assembly housing 100. 
Actuation rods 372 and 374 are pivotally connected along the length of 
lever arm 362 on opposite sides of the point of connection of hub assembly 
366 and lever arm 362. Actuation rods 372 and 374 are fixedly attached at 
their upper ends to pistons 120 and 122, respectively, and act through 
seals 372a and 374a seated in plates 108. The lower ends of actuation rods 
372 and 374 are pivotally joined to lever arm 362 by hub assemblies 376 
and 378, respectively, which threadedly receive the lower end of actuation 
rods 372 and 374. Hubs 376 and 378 are pinned for pivotal movement 
relative to lever arm 362 by axis pins 380 and 382. Rods 372 and 374 are 
engaged to pistons 120 and 122, by any suitable means such as by threaded 
engagement thereto. 
Referring to FIG. 5, it may be seen that by rotating lever arm 362 
clockwise in the direction of arrow 390, actuation rod 372 is pulled 
downwardly as the result of the pivoting of lever arm 362 about axis shaft 
364 thereby pulling piston 120 downwardly to unseat seal 152 from circular 
valve seat 210 of housing 100a. Simultaneously therewith, actuation rod 
374 is moved upwardly thereby unseating piston 122 from seal 154. Thus, 
fluid from port 44 is communicated along the path illustrated by arrow 332 
to port 46, and fluid entering port 48 follows the path illustrated by 
arrow 338 to exhaust port 74. 
Referring to FIG. 6, as the handle is rotated in the direction indicated by 
arrow 400, actuation rod 372 is raised to unseat piston 120 from seal 154 
and actuation rod 374 is lowered to unseat seal 154 from circular valve 
seat 242 of housing assembly 100a. In this configuration, fluid pressure 
input to port 44 is communicated along the path indicated by arrow 250 to 
port 48. Simultaneously therewith, fluid entering port 46 is communicated 
along the path indicated generally by arrow 252 and is exhausted through 
exhaust port 72. When no external force is applied to lever arm 362, the 
valve will assume the neutral or closed position illustrated in FIG. 2. 
This is the result of the forces exerted by springs 220 and 260 on poppet 
valves 124 and 126 and springs 222 and 262 on pistons 120 and 122. 
It will be noted that the valve configuration resulting from the rotation 
of lever arm 362 is identical to that resulting from the actuation of 
solenoids 77 and 78. Thus, the valve assembly is operable either 
electrically by the operation of solenoids 77 and 78 or manually by the 
rotation of lever arm 362. 
FIGS. 7 and 8 illustrate a manually operated valve assembly forming a 
second embodiment of the invention which comprises a modification of the 
embodiment illustrated in FIGS. 1-6. Many of the component parts of the 
second embodiment of the invention are substantially identical in 
construction and function to component parts of the embodiment described 
hereinbefore in conjunction with FIGS. 1-6. Such identical component parts 
are designated in FIGS. 7 and 8 with the same reference numerals utilized 
in the description of the first embodiment, but are differentiated 
therefrom by means of a prime (') designation. 
In the second embodiment illustrated in FIGS. 7 and 8, pistons 120' and 
122' are manually operated by actuation of handle assembly 360' which is 
mounted to the top of valve assembly 20'. Handle assembly 360' includes a 
lever arm 362' pivotally connected to valve assembly 20' by hub assembly 
366'. Lever arm 362' pivots about axis pin 364' which rotates in hub 370' 
of hub assembly 366'. Pistons 120' and 122' are pivotally attached along 
lever arm 362' on opposite sides of the attachment of lever arm 362' to 
hub assembly 366' by axis pins 380' and 382'. 
Pistons 120' and 122' are fitted with retaining pins 410 and 412, 
respectively. Actuator springs 414 and 416 are positioned around pistons 
120' and 122', respectively, and act between housing 100a' and retaining 
pins 410 and 412 which are fixedly attached to pistons 120' and 122'. The 
action of actuator springs 414 and 416 tend to center pistons 120' and 
122' to equalize the sealing pressure between pistons 120' and 122' and 
poppet seals 152' and 154' of poppet valves 124' and 126'. 
In the embodiment of FIGS. 7 and 8, exhaust ports 72' and 74' are formed 
through a bottom plate 418 attached to the bottom of lower housing 100a', 
but communicate with bores 172' and 174' of poppet guides 128' and 130', 
respectively, as in the first embodiment. Retaining rings 420 and 422 are 
seated on bottom plate 418 and are engaged by the lower end of poppet 
springs 220' and 260'. 
The operation of the valve illustrated in FIGS. 7 and 8 is substantially 
identical to that described with respect to the first embodiment except 
that the second embodiment must be manually operated. Referring to FIG. 8, 
by rotating lever arm 362' in the direction illustrated by arrow 424, 
piston 120' is raised and piston 122' is lowered in the valve assembly 
housing. As piston 122' is lowered, seal 154' of poppet valve 126' is 
unseated from circular valve seat 242' of housing 100a'. Thus, fluid 
entering inlet port 44' follows the path indicated generally by the arrow 
designated 250' and communicates with port 48'. Simultaneously therewith, 
piston 120' is raised and the seal between piston 120' and seal 152' of 
poppet 124' is broken. As a result, fluid entering port 46' communicates 
along the line indicated generally by the arrow 252' and exits exhaust 
port 72'. 
By rotating lever arm 362' in the direction opposite arrow 424, fluid 
entering inlet port 44' communicates with port 46' and fluid entering port 
48' exits exhaust port 74' in a similar manner to that discussed with 
respect to the first embodiment. Where no force is exerted on lever arm 
362', seals 152' and 154' of poppet valves 124' and 126' are seated 
against circular valve seats 210' and 242' by the action of poppet springs 
220' and 260'. Likewise, pistons 120' and 122' are seated against seals 
152' and 154' of poppet valves 124' and 126' by the action of springs 414 
and 416. Thus, with no force exerted on the lever arm 362', inlet fluid 
entering at inlet port 44' is prevented from communicating with either 
port 46' or 48' and ports 46' and 48' are sealed from communication with 
exhaust ports 72' and 74'. 
Thus, the present invention provides a four-way, three-position poppet 
directional valve which may be actuated electrically by a solenoid or 
other comparable actuating mechanism. The system also provides for a 
manual override of the valve operation as desired. The valve system is 
usable with all gases and liquids and provides a unique control design 
wherein the inlet fluid pressure functions to control the flow path of the 
fluid through the valve. 
Although preferred embodiments of the invention have been described in the 
foregoing detailed description and illustrated in the accompanying 
drawings, it will be understood that the invention is not limited to the 
embodiments disclosed, but is capable of numerous rearrangements, 
modifications and substitutions of parts and elements without departing 
from the spirit of the invention.