Faucet valve with early shutoff

A mixing valve includes a sleeve with axially spaced inlet and outlet ports and a valve member movable within the sleeve to control flow from the inlet to the outlet. There is a seal at the inlet port, which seal extends through the sleeve and into contact with the valve member. The valve member has a first portion adjacent the inlet port to control flow of the fluid therethrough and a second portion adjacent the outlet port to similarly control flow of fluid therethrough. The first and second valve member portions are spaced apart a distance such that movement of the valve member toward a closing position causes the second portion to close the oulet port before the first portion closes the inlet port thereby reducing pressure on said seal means at closure of said inlet port.

SUMMARY OF THE INVENTION 
The present invention relates to a mixing valve of the type utilizing a 
reciprocal valve member to control flow of fluid between the inlet and 
outlet ports of a surrounding sleeve. In particular, the invention is 
concerned with preventing damage to the seal members at the inlet port. 
This is accomplished by providing for valve closure at the sleeve outlet 
port just prior to closure at the sleeve inlet port thereby reducing the 
pressure upon the inlet port seal means at valve closure. 
A primary purpose of the invention is a mixing valve of the type described 
in which the reciprocally and rotatably movable valve member has portions 
positioned to provide closure at both the inlet ports and the outlet ports 
with the outlet port closure being arranged to take place just prior to 
closure at the inlet ports. 
Another purpose is a structure of the type described including means for 
preventing damage to the inlet port seal members at valve closure. 
Other purposes will appear in the ensuing specification, drawings and 
claims.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
The present invention relates to mixing valves, for example of the type 
generally shown in my prior U.S. Pat. No. 3,840,048. In a valve 
construction of this type there is what is known as a grommet type of seal 
which is positioned on the exterior of a sleeve and extends through the 
sleeve inlet port and into contact with a valve member reciprocally and 
rotatably movable within the sleeve. The valve member controls the flow of 
water through the valve structure. Such valve members are customarily 
found in kitchen, lavatory and shower-tub installations within a home. 
Because of the high pressures upon the grommet type of seal at the time of 
valve closure there has been a tendency for the valve member, when 
closing, to nip or cut or in some way abrade the seal member at shutoff. 
In time this will cause the seal to become leaky and thus the valve to 
become unsatisfactory. The present invention is specifically directed to 
reducing the high pressures upon this type of seal at the instant of 
closing. This is accomplished by providing a preclosure or early shutoff 
at the outlet port thereby reducing the pressures applied on the seal at 
the inlet at the time of complete valve closure. 
The invention will be described in connection with a specific type of valve 
structure which has become known in the trade as a valve cartridge. It is 
a completely contained unit which is positioned within a faucet or 
plumbing housing. The invention should not be limited to this specific 
structure. In like manner, the particular cartridge shown is one in which 
the valve member is pulled out to open the valve and pushed in for valve 
closure. The concepts disclosed herein are similarly applicable to a valve 
structure which is pushed in to open and pulled out for closure. 
As illustrated in FIGS. 1-3, the valve cartridge includes a sleeve 10 
having a pair of inlet ports 12 and 14 which will conventionally be 
connected to hot and cold water supplies. There are outlet ports 16 and 18 
in the sleeve and these ports will conventionally connect to a spout or 
other type of discharge device. The sleeve may have grooves containing 
seal rings 20 and 22 which will be in sealing contact with the interior of 
the faucet or plumbing housing. 
The inlet ports 12 and 14 include identical seal members 24 and 26 which 
may be of the type shown in my above-mentioned U.S. patent. Such seal 
members include body portions 24a and 26a, respectively, and port seal 
portions 24b and 26b, respectively, which port seal portions extend 
inwardly through the inlet ports and into sealing contact with the 
interior valve member. 
The valve member is indicated generally at 28 and includes a stem portion 
30 which extends outwardly through the sleeve and will conventionally 
mount a handle or other operating device. The inward end of the valve 
member includes a piston structure 32 which is hollow and which includes a 
notch 34 selectively movable into register with inlet ports 12 and 14 to 
control the flow of water therethrough. There is an interior seal ring 36 
which is in sealing contact with the inside of sleeve 10, thus preventing 
leakage at the interior end of the valve. In like manner, there is a seal 
ring 38 at the outward end of valve member 28 which prevents leakage 
outwardly from the valve cartridge along the stem portion 30. 
The valve member 28 includes an outlet port closure portion 40 which is 
generally cylindrical in shape and which will have an exterior diameter 
marginally less than the interior diameter of sleeve 10. This difference 
in diameters is somewhat exaggerated in the drawings for purposes of 
illustration. Cylindrical portion 40 will have a minimum clearance fit 
within the sleeve and will be effective to substantially close off the 
outlet ports 16 and 18 as described hereinafter. Cylindrical portion 40 is 
solid, whereas, the piston portion 32 is hollow. The two portions are 
joined together by a stem assembly 42. 
The hollow piston portion 32 may be formed as illustrated in FIG. 3. Notch 
34 may have a peripheral somewhat rounded edge 44, as particularly 
illustrated in FIG. 5. Note the inturned portions 46 which, when the valve 
member is moved toward closure, will prevent any sharp edge coming in 
contact with the port seal portions 24b and 26b of the grommet seals. In 
like manner, the upper or outer edge 48 of notch 34 may be formed in the 
manner of FIG. 4. Again, there is an in-turned portion 50 which will 
prevent any sharp edge coming in contact with the port seal portions of 
the grommet seals. Within piston 32 there may be a slanted interior wall 
52 which forms the rear wall of the notch and is adapted to direct water 
flowing inwardly through the sleeve ports in an axial outward direction 
along stem assembly 42 toward sleeve outlet ports 16 and 18. 
In operation, the closed position of the valve is illustrated in FIG. 1. 
Note that the grommet seals 24 and 26 are in sealing contact with the 
exterior cylindrical surface of piston 32. Note also that cylindrical 
portion 40 of the valve member has closed sleeve outlet ports 16 and 18. 
The full open position of the valve is illustrated in FIG. 2. Piston 32 
has been moved, with the stem, to the point where notch 34 is in register 
with port 12. The valve is rotatable so that the notch may be in register 
with portions of both ports 12 and 14 so that both hot and cold water may 
be introduced within the valve. In any event, the grommet seal is in 
contact with portions of piston 32 adjacent notch 34. Cylindrical portion 
40 has moved substantially beyond outlet ports 16 and 18. When the valve 
is moved toward the closing position of FIG. 3, there will be substantial 
pressure upon the grommet seals as the valve begins to close. The distance 
between the closing edge of notch 34 and the inner surface 41 of 
cylindrical portion 40 is such that surface 41 will completely close 
outlet ports 16 and 18 just prior to the time that piston 32 completely 
closes inlet ports 12 and 14. Because there is no rubber type seal at 
cylindrical portion 40, but only a minimum clearance fit, there may be 
some leakage at this point, but that is not important. There will be a 
substantial closure of all flow by the cylindrical portion 40 just prior 
to closure of the valve member at piston 32. The edge 50 of the upper 
portion of the notch 48 being in-turned, will not in any way cut or abrade 
the inner rim of port seal portions 24b and 26b as closure is 
accomplished. In like manner, in-turned portions 46 of edge 44 of the 
notch will similarly not provide any sharp edge as the piston moves past 
the grommet seals toward the closed position of FIG. 1. 
In the absence of a reduced pressure caused by cylindrical portion 40 it 
has been found in prior valve structures that the very high pressure upon 
the grommet seals just prior to closure will cause the seals to be pushed 
inwardly toward and in fact into the notch. In such event the actual 
closure by the upper surface of the notch can in fact cut or nip the seal 
as described previously resulting eventually in a leaky valve. By 
effectively reducing the pressure to a minimum level when closure is 
accomplished, the grommet seal cannot be pushed into the notch. 
Accordingly, the spacing between cylindrical portion 40, surface 41 and 
the notch of the piston 32 is highly important as this relationship 
provides the described early closure, thus reducing the pressure on the 
grommet seal. In like manner, additional protection against seal damage is 
provided by in-turned edges at those portions of the notch which contact 
the grommet seal at closure. 
Surface 41 of cylindrical portion 40 has been shown as substantially flat. 
It is within the scope of the invention to provide serrations or notches 
at this point to further modulate the water pressure at valve closure. The 
notches would not extend to such a point that they would permit any 
substantial flow of water at closure, but they would more gradually 
diminish the actual closing of the valve by the portion 40. 
Whereas the preferred form of the invention has been shown and described 
herein, it should be realized that there may be many modifications, 
substitutions and alternations thereto.