Universal momentary contact diverter

Universal momentary contact diverter valve is operated directly by axially disposed solenoid operators at each end of an elongated valve housing having a bore passing therethrough to receive a valving spool therein in an operable relationship with said solenoid operators so as to enable spool shifting directly to result in diversion of fluid flow passing therethrough and fluid exhaust therefrom via passages incorporated therein, energization of operator coils electrically accomplished momentarily by an application of voltage-overcharge-pulse to yield higher than conventional magnetic force.

This application relates to momentary contact solenoid operated diverter 
valves in general, and to a simplified momentary contact diverter valve 
that is operated directly by a solenoid operator in particular, 
characterized by valve operation wherein an electric pulse, not exceeding 
30 miliseconds in duration, causes position change of a spool resulting in 
flow redirection by such valves be it liquid or gas, universaly. 
Internally piloted momentary contact reversing diverter, disclosed in the 
parent invention identified above, describes characteristics novel to the 
state of the art in valving. Although, because of the pilot pressure force 
internally piloted valves entail, such valves have no practical limits as 
to the system pressures or drag forces they can serve, the fact remains 
that there are too numerous application prohibiting the use of piloted 
designs due to many reasons, such as hazardous fluids that can not be 
exhausted from the solenoid cavity safely, and/or that there is only 
marginal pressure in the system such valves serve, or that the system is 
not conducive to the use of piloted valves, to name a few of such reasons. 
It was determined, however, that the internally piloted fluid passages 
inside valve spool of the parent invention can serve well as fluid exhaust 
means in valves operated directly by solenoids of the present invention, 
thereby simplifying such valves. Further, it was established 
experimentally that cutting off fluid exiting a port, by a piston of a 
spool includes a sizeable fluid force, which force is purely depedent on 
pressures of the fluid valved, coupled with configuration and size of the 
passage fluid is flowing through before being cut-off. Unless the spool is 
internally piloted to permit fluid force aid in spool shifting while 
crossing central fluid supply port, large in size, often feeding a narrow 
slot offering reduced stroke for spool shifting inside valve while 
maintaining large fluid flow capacity, pilotless direct solenoid operated 
spool shifting must first consider the availability of a magnetic force 
solenoid coils can provide directly to the spool ends, for a similar 
action the plungers of the internally piloted(parent)reversing diverter 
operated, in order to insure proper valve operation. In final analysis, it 
was deduced that a direct operated momentary contact diverter valve can be 
designed so that the spool can be shifted by a magnetic force solenoid 
coils provide without any consideration to the pressure cut-off forces 
fluid produces. This was possible by the use of two seals for control of 
flow redirection and diversion of pressurized fluid from entrance port in 
lieu of a single seal shown in the parent diverter performing fluid 
cut-off when spool is shifted, thereby departing away from the original 
diverter design in-part. Further, by selecting solenoid coils with lower 
electrical resistance as measured by Ohms, additional gain materialized in 
that the coils with lower resistance were momentarily voltage overcharged 
for higher magnetic pull force without overheating, departing 
substantially from the conventional practice wherein coils must be sized 
in accordance with service type, to prevent burn-out. The object of the 
present invention is, therefore, to provide a direct solenoid operated 
simple diverter valve with spool ends of valving means acting as solenoid 
plungers capable of magnetic shifting for flow redirection through the 
valve, for universal use. 
Another object of this invention is to provide a novel momentary contact 
valve which is simple to manufacture, assembly and maintain, and in 
particular to operate with practically negligible power requirement 
electrically in new applications universally. In this connection, the 
valve of present invention consists of basically two components, namely a 
valve housing with a single bore passing therethrough and a simple valve 
spool slidably received therein, plus two end solenoid operators secured 
at each opposite housing ends by threads for momentary energization 
electrically resulting in instant spool position change when one of the 
solenoid coils exerts larger than conventionally accepted magnetic pull 
force due to voltage overcharge pulse of a very brief duration over one of 
spool ends provided with magnetic material, to serve pressures and fluid 
flows therewith of considerably larger magnitude than those attainable by 
conventional valves, thereby greatly improving the state of the art in 
solenoid valves in general and in momentary contact solenoid valves in 
particular, since there are no direct operated solenoid valves of 
momentary contact with such capabilities in existance, in particular-with 
exhaust passages inside stem of the spool. These and other objects and 
advantages of the invention will become more fully apparent from the 
following description of an embodiment of the invention, taken together 
with the accompanying drawings.

Shown in FIG. 1 is an assembly of a momentary contact diverter 1 operated 
directly by a pair of solenoid operators 6. An elongated valve housing 2 
is shown to have a bore 3 passing therethrough including fluid port 4 
entering bore 3 perpendicularly through a wall, along with ports 4-a and 
4-b spaced a short distance away therefrom. A slidably movable valving 
spool 5 with stem 7 inside housing bore 3 having ends 7-a and 7-b protrude 
housing ends 2-a and 2-b respectively into the solenoid cavities 9 
comprising in effect an extension of bore 3 is in an operable relationship 
with solenoids 6, wherein when a first solenoid coil 8 of a first solenoid 
operator 6-a is electrically energized by a surge of voltage overcharge 
for a short period in miliseconds, preferably below 30 miliseconds, to 
result in a large magnetic pull force over first spool end 7a capable of 
attracting spool 5 to and maintaining in the position shown in FIG. 
1-left, the second spool end 7-b inside cavity 9 of a second solenoid 
operator 6- b forms an end gap 10 between a stop 13 and end 7-b shown in 
FIG. 1, while when a second solenoid coil 8-a of a second solenoid 
operator 6-b becomes electrically energized momentarily, the reversal 
takes place and the valving spool becomes shifted by the magnetic pull 
force surrounding a second extreme spool end 7-b to the right, to have a 
second identical end gap formed in the opposite cavity of solenoid 
operator 6-a (not shown), and vice versa, wherein a brief energization of 
either of solenoid coils electrically provides powerful means of spool 
position change inside bore 3, accomplishing change in flow direction 
through the valve be it 2-ported valve wherein a third port shown in FIG. 
1 is blocked or tree ported valve as illustrated therein, without further 
use of electrical power between the momentary energization periods which 
normally constitute a short pulse service, adaptable for higher voltage 
applications to conventional coils without the fear of overheating them. 
A piston 14 with stem ends 7 of spool 5 is shown to have seals 11 and 11-a 
permanently secured therein and movable along with spool 5 during diverter 
operation so as to permit port 4, entering bore 3 substantially in the 
middle of housing 2, to alternatingly communicate with ports 4-a and 4-b, 
spaced a short distance apart toward housing ends and sealed by a pair of 
stationary seals 12 and 12-a inside counterbores of housing ends 2-a and 
2-b respectively. Port 4 is shown to have a flow recess 3-c of a diameter 
slightly larger than the diameter of bore 3 but of narrow width. And when 
spool 5 is in a first location shown left in FIG. 1, fluid entering port 4 
is directed to port 4a via annulus 3-b, formed between bore portion 3a and 
reduced diameter spool section 5-a, protected by stationary seal 12-a and 
movable piston seal 11 engaged inside bore 3 adjacent port 4-b while seal 
11-a is disengaged therefrom inside recess 3-c. Flow between ports 4 and 
4-b is prohibited until spool 5 is shifted to the right when coil 8a is 
energized. 
When spool 5 is shifted from the position shown in FIG. 1, seal 11-a will 
block-off port 4-a allowing fluid communication to proceed from port 4 to 
port 4-b via annulus 3-d, and vice versa. Alternatingly, seals 11 and 11a 
will engage bore 3 on sides of flow recess 3c. Port 4 in reality is not 
subjected to a cut-off by a single seal shown and claimed to perform flow 
diversion function in the parent application. Instead, when seal 11 
engages, seal 11-a disengages simultaneously without upsetting continuity 
of flow. No drastic fluid forces develop during flow reversals by this 
diverter since present design employs two seals to control direction of 
fluid entering and leaving valve proper. This type of sealing pemits 
control of large pressures without undue requirement for larger magnetic 
forces for spool shifting. Also, flows are considerably larger through the 
valve using dual seals. Ergo, smaller and less costly solenoid coils can 
be used here. 
Further, spool of this invention can be provided with integral fluid 
passages which can be of overlapping arrangement as shown in FIG. 1 or 
they can be drilled inside spool ends to serve as flow exhaust means shown 
in FIG. 2. 
In FIG. 1 flow passages 14-a inside spool 5 initiate on piston side 15 
while flow passages 14-b inside spool 5 initiate on piston side 15-a to 
proceed in an overlapping arrangement so as to exhaust via flow passages 
at spool ends 7-b and 7-a respectively into the solenoid cavities 9 to 
exhaust into the open via exhaust ports 13-a and 13-b of solenoid stops 13 
respectively, depending on the position spool is allowed to assume axially 
inside bore 3. Shown in FIG. 1 is spool position wherein exhaust port 13-b 
is blocked off by the taper of spool end 7-a allowing receiver port 4-b to 
exhaust via spool pilot port 14-a and exhaust port 13-a while receiver 
port 4-a is in communication with fluid supply port 4 which position is, 
incidentally, maintained driftless by the fluid action over piston 14 
shown of diameter larger than the spool ends until the solenoid coil 8-a 
is energized momentarily to change spool position diverting fluid flow 
through the valve, and vice versa. Obviously, valves shown in FIG. 1 and 
FIG. 2 can be used for flow reversal between ports 1, 2 and 3 without 
utilization of exhaust ports, which are optional. Optional fluid passages 
14-a and 14-b inside spool 5 are intended to serve system requirements 
calling for fluid exhaust only. Otherwise, diverter of FIG. 1 may be 
provided with either tapered spool ends if such diverters serve in direct 
current applications, such as battery actuated field irrigation systems, 
or they may have flat spool ends as that shown in FIG. 2. Likewise, having 
seals 12 and 12-a fixed inside respective housing ends 2-a and 2-b while 
spool ends 7-a and 7-b respectively slide on inside seal diameters, less 
friction is generated by the seals during spool shifting axially. Finally, 
since seals 11 and 11-a travel axially very little, and since seals 12 and 
12-a are detacheable, valve manufacture and assembly, as well as 
maintenance are reduced to the bare minimum. 
Obviously, if port 4 is designated to be fluid supply port, ports 4-a and 
4-b then become fluid receiver and exhaust port means alternatingly 
communicating with supply port 4 when valving spool 5 is shifted between 
solenoid operators 6-a and 6-b, consistent with operation of typical 
diverters or reversing valves used in solar heating, air-conditioning/heat 
pump systems, process or automation control. However, port 4 may equally 
become a receiver port in systems requiring mixing of two fluids supplied 
via ports 4-a and/or 4-b alternatingly, or individually. In such cases 
diverter becomes a mixer valve of momentary contact, direct solenoid 
operated design, requiring consideration of supply pressures, because 
often fluids to be mixed are subject to presure variation which may 
develop large end forces over sides of piston 14 of FIG. 1. Such forces 
may require large solenoid operators, and may render such diverter valves 
limited in applications, unless piston of FIG. 1 is modified to a spool 
piston of that shown in FIG. 2 eliminating large diameteral variations in 
spool, detrimental to high pressure applications. 
Shown in FIG. 2 identifying simple diverter valve for universal use, 
operated by identical solenoid operators 6 is an elongated valve housing 
20 with a bore 23 passing therethrough including fluid ports 24, 24-a and 
24-b entering bore 23 perpendicularly through a wall 22, and a slidably 
movable valving spool 25 with ends 27-a and 27-b protruding housing ends 
20-a and 20-b respectively into solenoid cavities 39 comprising 
essentially extension of bore 23 to permit an operable relationship 
between solenoids 6 and spool 25, in an identical fashion diverter of FIG. 
1 operated. 
The difference in spools 5 of FIG. 1 and 25 of FIG. 2 requires slight 
modification of housing bore 23 of FIG. 2 in that if the diveters are to 
serve identical fluid flow, bore 23 may have diameter identical to bore 3, 
at least in the center section 23-a with port 24 while bore sections 29 
and 29-a that serve ports 24-b and 24-a respectively may have slightly 
larger diameters adjacent stationary seals 32 and 32a respectively, 
forming a fluid annulus 26 between a stem 28 of spool 25 at ends 27-a and 
27-b, as shown in FIG. 2, including fluid exhaust passages 30 and 30-a 
inside spool ends 27-b and 27-a respectively, and a plurality of radial 
exhaust holes 31, clearly visible in cross-sectioned spool end 27-b as 
well as inside spool end 27-a at 31-a adjacent seal 32-a. Note that when 
spool is in position shown in FIG. 2, port 24-b is open to exhaust via 
holes 31 and exhaust passage 30 of spool end 27- b, and exhaust port 13-b 
of the solenoid stop 13, while the exhaust means at the opposite spool end 
27-a are disconnected from annulus 26 until spool 25 is shifted to change 
position inside bore 23 (not shown) allowing port 24-a to exhaust via 
holes 31-a facing annulus 26 in communication with exhaust passages 30-a 
and 13-a, and vice versa. The spool seals 33 and 33-a during spool 
position change, alternatingly enter bore section 23-a to either permit 
fluid communication between ports 24-a or 24-b regardless of provisions of 
optional exhaust spool ends may have. 
Design modification identified in FIG. 2 may, indeed, serve many 
applicational needs universally, except for very large flows which may 
preferably be handled more easily by the design shown in FIG. 1, if 
pressures are low, since holes 31 and 31-a of spool 25 of FIG. 2 may be 
limited to the stroke which, in direct solenoid operated valves, is 
controlled by the magnetic forces solenoid coils can develop, limiting 
their capacity. 
Like in FIG. 1, seals 33 and 33-a of FIG. 2 generate little frictional 
resistance, rendering diverter ideally suited for substantially large 
number of applications with high system pressures, unlike the design 
modification depicted in FIG. 1 with large piston. 
It must be noted that spools of FIG. 1 and FIG. 2 must be produced either 
from iron or magnetic materials known as ferritic, including stainless 
steels from ferritic group 400 series such as 410 or 430 stainless if they 
are made as solid one piece spools, or if they are produced from other 
materials in order to satisfy specific requirements calling for wetted 
surfaces of the spool to be made from plastics or other non-ferritic 
materials such as aluminum, spool ends that enter operator cavities must 
be ferritic in order to insure spool shifting by a magnetic force solenoid 
coils generate when energized electrically. Likewise, spool ends may be 
increased in diameter above that of dual seals considerably more than 
shown in FIG. 2, to insure driftless spool position selected. 
Other changes eliminating or adding certain specific structural or 
procedural details may be made in the above described diverter without 
departing from the invention.