Swivel valve

This invention relates to a faucet valve for controlling the rate of flow of fluid from a first conduit usually to a second conduit in which there is provided a valve stem adapted by means of an externally threaded collar to be mounted and retained in a faucet housing and a swivel valve attached to one end of the foregoing valve stem by engaging or gripping means including a plurality of spaced resilient elongate arms disposed circumferentially about the body of said valve and terminating in a series of fingers or detents retained in, but detachable from, an annular groove formed in the valve stem, and contiguous with the button or flattened knob or foot forming the adjacent end of the valve stem. The valve body is modified on one surface to provide a resilient snap-on engagement of the foregoing arms and fingers with the valve stem.

TECHNICAL FIELD 
This invention pertains to a valve assembly for faucets. 
BACKGROUND OF THE ART 
It has been known in controlling fluid flow through a faucet heretofore to 
provide a valve cooperating with a stationary valve seat wherein the valve 
is adapted to abut the rim of the valve seat in the closed position and to 
be removed therefrom in the open position so that fluid is permitted free 
egress from an inlet pipe through the valve chamber containing the valve 
and valve seat and thence through the outlet pipe into a sink or other 
fixture. 
In returning the valve to the closed position it has proven necessary, in 
order to assure a positive and continuous seal between the valve and valve 
seat, obviating leakage through the outlet pipe or conduit, to provide for 
and overcome misalignment resulting from variations in temperature, 
mechanical factors and the like that often occur, at least over a period 
of time, between the valve and valve seat as well as irregularities in the 
rim of the valve seat itself. This has been accomplished heretofore with 
varying degrees of success by a multiplicity of different means known 
generically as swivel valves. 
In order to avoid or limit substantially the erosion of the valve surface 
and the valve seat in the abutting closed position it has proven 
efficacious to provide that the valve be attached to the valve stem in 
such a manner that when the valve stem is rotated to close the valve, the 
valve may upon reaching an effective sealing position in the valve seat, 
assume a stationary posture, although, as frequently occurs, the valve 
stem is further rotated to increase the pressure on the valve and the 
abutment between valve and valve seat. 
A variety of swivel valves have also been proposed to effect this purpose. 
Generally they have resulted in a multiplicity of component parts 
requiring a carefully balanced and calibrated relationship, awkwardness 
and significant cost in manufacture and assembly; the use of resilient 
materials susceptible to fatigue or deterioration over limited periods of 
time; the substitution of substantial erosion at the point of engagement 
of the valve with the valve stem for that occurring otherwise at the 
abutting surfaces of the valve and valve seat; and indeed, in some 
instances, a reduction in the effectiveness of the fluid seal to decrease 
erosion by use of less effective sealing materials which have better 
wearing properties. 
In the event, therefore, that a swivel valve could be devised that would 
permit ready and economic manufacture and assembly, a simple valve 
construction incorporating a limited number of parts or an integral 
element capable of accommodating readily for misalignment in relation to a 
stationary valve seat and independent rotation of the valve stem when the 
valve is in an abutting position with the valve seat, and that would, at 
the same time, be composed of a long wearing material or materials that 
would assure an effective fluid seal and eliminate erosion substantially 
between valve and valve seat and minimal friction between valve stem and 
valve, a significant advance in the state of the art would be attained. 
DISCLOSURE OF INVENTION 
This invention provides, accordingly, a faucet valve for controlling the 
rate of flow of fluid from a first conduit usually to a second conduit in 
which there is provided a valve stem adapted by means of an externally 
threaded collar to be mounted and retained in a faucet housing and a 
swivel valve attached to one end of the foregoing valve stem by engaging 
or gripping means composed of a plurality of spaced resilient elongate 
arms disposed circumferentially about the body of said valve and 
terminating in a series of fingers or detents retained in, but detachable 
from, an annular groove formed in the valve stem, and contiguous with the 
button or flattened knob or foot forming the adjacent end of the valve 
stem. The valve body is modified on one surface to provide a resilient 
snap-on engagement of the foregoing arms and fingers with the valve stem. 
The foregoing arms abut the annular side walls of the valve stem button or 
foot and in one embodiment the flattened under and outer surface of the 
button is in abutting relation with the flattened upper or bearing surface 
of the valve body about the periphery of which are arrayed the foregoing 
arms, thus effectively distributing the stress on the resilient valve arms 
when the valve body is compressed in a closed position. 
In a preferred embodiment, a portion of said upper bearing surface disposed 
about the stem axis may form a recess, thus reducing the bearing surface 
between the valve body and valve stem and concomitantly the coefficient of 
friction between the valve and valve stem by providing a reservoir or well 
filled with entrapped fluid, such as water (or any other liquid being 
conveyed or regulated by the valve) which acts as a low-friction, liquid 
bearing between the two components. The upper rim of the stem groove 
engaging the foregoing fingers or detents is, in accordance with the 
invention, spaced from the bearing surface, whether the recess is present 
therein or not, a distance greater than the length of the arms to which 
the fingers are attached, thus precluding an increased frictional load 
between the fingers and the upper outwardly extending limit of the annular 
groove. The valve body is modified on its opposite surface to form a 
circumferential recess, in which is disposed a compressible washer which 
is secured in place by ultrasonically upsetting the central projection and 
thus forming the inverted dome. 
The unique construction of the valve and its engagement with the valve 
stem, provides a valve assembly of simple and effective structure capable 
of adapting to misalignment of the valve with the valve seat while 
permitting independent movement of the valve stem with respect to the 
valve when the latter is in abutment with the valve seat and in a 
stationary position and accomplishing an effective seal in this position 
with substantial elimination of friction between the valve and valve stem. 
These and other advantages will be evident from the description appearing 
hereinafter in context with the appended drawings.

BEST MODE OF CARRYING OUT THE INVENTION 
Referring to the drawings, and with reference particularly to FIGS. 1, 2 
and 3 thereof, the valve assembly 10 of the invention comprises a valve 
stem 12 and a swivel valve 14. 
The stem 12 formed normally of brass, or usually less desirably, stainless 
steel or plastic is threadedly mounted on the internally threaded upper 
portion of the stem nut or sleeve 16 as shown in FIG. 1 which is, in turn, 
about its outer lower portion, threadably engaged with the valve housing 
17 and seat upon the interposed sealing ring 18. Upon the splined expanded 
stem head 19 of the stem 12 is mounted the faucet handle 20 to provide for 
rotation and axial or rectilinear movement of the stem valve 12 and axial 
movement of the valve 14 attached thereto in the manner and to the extent 
described elsewhere herein. The faucet handle 20 is otherwise secured to 
the stem head 19 by a screw 22 received in the threaded interior of the 
recess 24 axially disposed in the stem head 19 under the faucet index cap 
21 and continuing into the body of the stem 12. 
Below the threaded exterior 26 of the valve stem 12 there is provided an 
upper or first circumferential groove 28 in which is disposed an O-ring 29 
(as shown in FIG. 1). This first groove 28 is bounded and defined on its 
upper side by the first annular flange 30 on its lower side by a similar 
second annular flange 31. The flange 30 is adapted to engage the lower 
margin of the internally disposed threads of the sleeve 16 when the valve 
stem 12 and valve are moved outwardly of the valve chamber 32, in which 
they are mounted, and away from the valve seat 60, defining the maximum 
valve open position attainable by the valve assembly 10. The second lower 
flange 31 is interposed between the foregoing upper groove 28 and forms 
the upper margin or rim of a second annular groove 38 below and parallel 
to the upper groove 28. The O-ring is employed to preclude leakage about 
the valve stem 12 from the valve chamber 32 positioned between the ends of 
the inlet conduit 36 and outlet conduit 34. The O-ring 29 also performs an 
auxiliary role in providing a minimal but desirable resistance to rotation 
of the stem valve, tending, as a result, to inhibit abrupt rotation of the 
handle 20 and the valve assembly 10. 
The second, lower, parallel groove 38 is defined, as indicated, in the 
valve stem 12 by the annular flange or rim 31 and the upper border of the 
expanded radially flattened stem button or foot 40 of the unitary valve 
stem 12. 
As shown in FIG. 1, that portion of the valve stem 12 commencing with the 
annular groove 38 and extending to the foot 40 are disposed below the 
level of the stem nut 16 when the valve stem 12 and valve 14 are in the 
closed position. 
The swivel valve 14 is an integral plastic structure composed preferably of 
a polyacetal or polyamide (nylon) resin composition and comprises a body 
portion 41, the outer overlapping periphery of which is modified to 
provide a plurality of upwardly projecting evenly spaced arms 44 
terminating in a like number of inwardly directed fingers or detents 46 
adapted for snap-on engagement in the foregoing lower annular valve stem 
groove 38. The arms 44, for stability and resistance to fracture, also 
abut the sides of the button or foot 40, but the fingers and arms are so 
constructed in a significantly preferred embodiment as to embrace 
respectively no more than one-third of the groove 38 and lateral surface 
of the stem foot 40. 
The valve 14 is, in one embodiment of the invention, also adapted on its 
upper surface to conform to, abut and overlap the cooperating flattened 
surface of the stem button or foot 40, thus distributing the stress to 
which the arms 44 would otherwise be vulnerable. The valve body 41 is, 
therefore, flat across its upper surface to accommodate to the flat outer 
surface of the stem button or knob 40. It will be obvious that these 
abutting surfaces can be modified to present a variety of complementary 
configurations within the confines of the present invention. In a 
preferred embodiment, where present as an abutting or bearing surface, a 
flattened cooperating plane is preferred in that, while the contact of the 
stem surface with the valve body is complete, it is minimal as contrasted 
with that which modified contours would provide. 
In a particularly preferred embodiment, however, the surface disposed 
coaxially and concentrically within the periphery of said arms 44 is 
modified to form a recess 42 which limits the bearing surface contact with 
the stem foot or knob 40 to the shoulders 43 defining the recess borders 
and the full extent of the bearing surface in contact with the stem foot 
40. The recess 42 provides a well or reservoir for the fluid, that is, the 
liquid such as water, which is being transmitted through the valve which 
acts as a low-friction, liquid bearing when entrapped between the surfaces 
of the two parts. 
It is believed, without however, intended to be limited by any particular 
theory of operation, that the liquid entrapped in the recess 42 carries a 
substantial portion of the downward force that is imparted by the valve 
stem 12 to the swivel valve 14. It is believed that this liquid is placed 
under pressure immediately outboard of the recess entrapping the water 
therebetween and providing the significant advantage of a liquid thrust 
bearing with very low friction. 
The area of abutment of arms and fingers with the groove 38 and lateral 
button surfaces will, of course, vary with the composition forming the 
body of the valve body 41. It has been found particularly functional, as 
well, to provide four such arms 44 and terminal fingers 46 although as few 
as three and as many as five, or indeed, six much arms 44 and fingers 46 
may be utilized effectively. 
The arms 44 and fingers 46 occur in a preferably, evenly distributed and 
spaced relation about the periphery of the top side of the valve body 41 
as illustrated particularly in FIG. 4. 
It is essential, in any event, that the valve 14, including the arms 44 and 
fingers 46, be formed of a water-insoluble, hard, self supporting, 
non-corrosive, non-compressible, non-absorptive, chemically resistant 
synthetic polymeric composition, and most desirably a thermoplastic 
polyacetal resin, in which the arms and fingers are, in the dimensions 
employed in the practice of the invention, resilient, whereas the 
remainder of said valve formed of the same material (exclusive of the 
washer described hereinafter) is rigid. Significantly preferred is a 
polyacetal resin and indeed a polyacetal copolymer having a dynamic 
coefficient of friction in contact with steel or brass or plastic 
(normally an engineering plastic, such as a polyacetal) of about 0.10 to 
about 0.35, and preferably about 0.15, as measured by ASTM Test Method 
D-1894; a Rockwell hardness M-scale of about 30 to about 85 as measured by 
ASTM procedure D 785; a flexural strength at 5 percent deformation using 
ASTM D-790 of from 10,000 psi to 15,000 psi and preferably about 13,000 
psi; and an elongation of 40.degree. F. of 15 percent to 30 percent, and 
preferably about 45 percent to 75 percent, and most desirably about 20 
percent, and at an ambient temperature of 73.degree. F. of 60 percent, 
employing ASTM D-638 Speed B. The preferred polyacetal resins for use 
herein are those resins having a melt index of from 7 to about 27. 
Polyacetal resins for use herein are sold under the trade designation 
CELCON by Celanese Corporation and most desirably that designated Celcon M 
90-04 and those marketed under the trademark DELRIN by the DuPont 
Corporation, Wilmington, Del. The coefficient of friction of a polyacetal 
resin for use in forming the swivel valve of the present invention may be 
further reduced where desired by use of a polymeric compound or 
composition such as poly(tetrafluoroethylene) marketed by the DuPont 
Corporation under the trademark TEFLON, alloyed or admixed with the base 
resin, such as the foregoing polyacetals. 
Another resin useful in forming the valve of the invention (exclusive of 
the compression washer) is nylon having properties equivalent to those 
recited for the polyacetal resins characterized hereinabove. 
The under or lower surface of the valve body 41 is modified about its outer 
periphery to form a cylindrical, vertically and downwardly disposed flange 
or skirt 48, a concentrically arranged annular recess 50 and a centrally 
positioned neck 51, the end of which is ultrasonically upset to form the 
retaining head or dome 52 which confines and secures the compression 
washer 56 into recess 50 by means of the annular shoulder 53 in such a 
manner as to form an integral unit with the remainder of the valve. In a 
particularly preferred embodiment, the flange 48 does not embrace the 
entire side wall of the compression washer 56 nor does the flange 48 
descend to a level corresponding to that of the shoulder 53 at the base of 
the dome 52. This is so in order that the hard or rigid polymeric 
composition of the valve 14 does not descend to a level where it will 
affect the mating of the washer with the rim 58 of a cooperating valve 
seat 60 that extends into the valve chamber 32 and is threadably mounted 
in the housing 17. In this way, the washer 56, formed of an elastomeric 
compressible composition such as natural or synthetic rubber, will be 
permitted a lateral expansion when compressed against the valve seat 60 to 
better assure an effective fluid seal. 
While the swivel valve is formed from a limited group of thermoplastic 
resins, and as indicated, most desirably a polyacetal copolymer (including 
terpolymers) of inherent lubricity having a coefficient of dynamic 
friction within the range of 0.10 to 0.35 and other physical properties 
such as described hereinabove, the valve washer is formed of an 
elastomeric polymer such as natural or synthetic rubber. The elastomers 
for use herein include, illustratively, in addition, to synthetic and 
natural polyisoprene, poly (chloroprene), GRS, Buna-S styrenebutadiene 
copolymers, poly (isobutylene-isoprene) and the like. The elastomer, 
whether one of the foregoing or another, such as are well known to those 
skilled in the art, is one characterized, in a significantly preferred 
embodiment, by a durometer hardness as determined by a durometer gage 
according to ASTM D 2240-68, read using a Type A scale, of within the 
range of 65 to 75 and preferably about 70; a minimum tensile strength as 
determined by ASTM D 412 of 600 psi. min. up to 1500 psi and, indeed, up 
to 2000 psi. min., but normally about 1000 psi. min; with a compression 
set resistance according to ASTM D 395 Method B of about 40 percent to 
about 10 percent; and preferably in the latter portion of this range, i.e. 
20 percent to 15 percent. 
The dome 52 of the valve 14 is most desirably of an arcuate configuration 
to facilitate a smooth path for the flow of water. It is desirable that 
the dome 52 extend appreciably beyond the diameter of the hole of the 
washer 56 for the purpose of providing an effective retaining member or 
shoulder 53, but that the dome 52 avoid being so obtrusive that it hinders 
the free passage of fluid through the valve chamber 32 when the valve 14 
is removed from the valve seat 60 and is in the open state. 
The annular and concentric disposition of the dependent flange 48, washer 
56 and dome 52 of the valve 14 are further illustrated in FIG. 5 of the 
drawings. 
A valve assembly, as thus described, permits for adjustment of the valve to 
any misalignment that may occur in the relation of the annular valve 
washer 56 to the underlying stationary valve seat 60 and also permits for 
free rotation of the valve stem 12 when the valve 14 is impressed on the 
valve seat 60 with consequent elimination of friction therebetween without 
a compensating increase of the frictional coefficient occurring between 
the valve 14 and the valve stem 12; indeed with a minimization of such 
friction that is surprising in view of the secure engagement with 
accommodation for swivel adjustment achieved by the engagement of the 
valve 14 to the valve stem 12 in accordance with the invention. 
The arms 44 and fingers 46 are, as aforesaid, critical to effect this 
swivel adjustment. It is significant that the fingers 46 are so removed 
from the bearing surface in a preferred embodiment as to avoid abutting 
the flange 31 defining the upper limit of the stem groove 38, particularly 
when the compression washer 56 is impinging upon the valve seat 60; thus 
precluding any possible frictional engagement between the upper surfaces 
of the fingers 46 and the corresponding under surface of the flange 31. 
The elastomeric compressible composition of the washer 56 and the rigid, 
but selectively resilient, character of the remainder of the valve 14 are, 
as has been made evident elsewhere, also significant in achieving the 
advantages of the present invention. 
It will be evident that the elastomeric and rigid but resilient 
compositions of the valve assembly must not degrade at the temperatures of 
the fluids passing through the valve system employed in accordance with 
the invention or be chemically reactive with or absorptive of these 
fluids. 
It will be evident, too, that the terms and expressions that have been 
employed herein are used as terms of description and not of limitation. 
There is no intention in the use of these terms and expressions of 
excluding equivalents of the features shown and described and portions 
thereof, and it is recognized that various modifications are possible 
within the scope of the invention claimed.