Note: Descriptions are shown in the official language in which they were submitted.
~ 7~'19
This application is related to copencling Canadian
application Serial No. 227,203 filed May 16~ 1975 which in
turn is a division of Canadian application Serial No. 171,362
filed ~lay 15, 1973, now Canadian Patent 980,318 issued
December 23, 1975.
BACKGROll~lD AND SUIi~MA~Y OF THE INVENTION
,
The present invention relates to a servo-actuated
valve particularly suited for, although not limited to~ use
in automobile heating systems.
Heretofore, problems which individually and collectively
have beset valves of this type, to various dearees~ include;
internal leakage preventing the valve from completely blocking
fluid flow when closed especially at low fluid pressures and often
caused by wear and foreign matter in the fluid; binding of the
valve actuating mechanisn and linkage preventing the valve from
being smoothly and reliably actuated; the need for complicated
manufacturing and assembly operations; relatively heavy weight
often necessitating positive mounting to the vehicle by a separate
mounting bra~ket; inability to consistently reliably operate over
20 the temperature extremes to which subjected; ~oor sealing o the
servo diaphragm to the servo actuator arm; and lack of strength
in the servo housing when fabricated from inexpensive materials.
Accordingly, important objects of the present invention
are to eliminate, or at least alleviate, the foregoing problems,
including providing: a valve which is sufficient1y lightweight
that it can be hung directly in a heater hose linel an im.proved
sealing arrangement for a valve in which resilient means con-
tinually biases the valve element into sealing engagement with the
29 valve seat, which also uses the pressure of the input :Eluid to~
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assist in sealing, which reliably closes even at very low fluid
pressures, which in one alternative embodiment contains additional
means to insure the proper operation of the valve at high
pressures, and which is highly resistant to foreign matter and
temperature variations; a valve which is relatively inexpensive
and well-suited for mass production; an improved arrangement
for interlocking the two halves of a vacuum servo housing which
both strengthens the housing and seals the outer periphery of the
servo diaphragm; a vacuum-tight seal for a servo diaphragm for
preventing leakage around the connection of the servo actuator
arm to the diaphragm; a simplified connection between the servo and
the valve actuating member which requires no separate fastener,
which minimizes backlash and any tendency to bind, which is easy
to connect and which, once connected, cannot become disconnected
during operation.
Broadly speaking the present invention may be defined
as a fluid valve comprising: a housing having a chamber therein;
means defining inlet and outlet passageways communicating with
the chamber; a valve element disposed in the chamber rotatable
about an axis between a closed position in which flow from the
inlet passageway to the outlet passageway is blocked and an open
position in which the flow is not blocked; and elastomeric sealing
element disposed about the periphery of the outlet passageway ~:
j between the adjacent wall of the chamber and the valve element, the
valve being arranged so that the valve element is urged against
the sealing element by the pressure of inlet fluid in all positions
of the valve element, and securing means for preventing the
elastomeric sealing element from extruding into the outlet passage
way under the pressure of the inle fluid on the valve element,
- 2 -
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the securing means including at least one hole formed in either
the sealing element or the housing adjacent the periphery of
the outlet passageway and at least one complementary protrusion
integral with the other of the sealing element or the housing,
the protrusion being disposed within the hole.
- 2a -
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.
BRIEF D:I~SCRIPTION OF T~113 DRAI'7IN(.S
The accompanying drawings illustrate the invention in
accordance with the best mode presently contemplated for carrying
out the invention.
Fig. 1 is a top plan view of the servo-actuated valve
unit of Canadian application Serial No. 227,203.
Fig. 2 is an enlarged vertical sectional view taken
along line 2-2 of Fig. 1.
Fig, 3 is a vertical sectional view taken along line
3-3 in Fig. 1.
Fig. 4 is an enlarged fra~mentarv horizontal sectional
view taken along line 4-4 in Fig. 3.
Fig. 5 is an enlarged fragmentary horizontal sectional
view taken along line-5-5 in Fig. 2.
Fig. 6 is an enlarged view taken in circle 6 of Fig. 3.
Fig. 7 is a plan view showing the~ valve spring of the
unit by itself.
Fig. 8 is a plan view showing the valve seal by itself.
Fig. 9 is an enlarged view ~aken in circle 9 of Fig. 3.
Fig. 10 is an enlarged fragmentary horizontal sectional
view taken along line 10-10 in Fig. 3.
Fig. 11 is an enlarged vertical sectional view similar
to Fig. 2 showing the present invention.
Fig. 12 is a horizontal sectional view taken along line
12-12 in Fig. 11.
I Fig. 13 is a plan view of the valve sp~ing element incor-
i porated in the embodiment shown in Fig. 11.
Fig. 14 is a plan view of the valve seal incorporated
~, in the embodiment oE Fig. 11.
1 30 Fig. 15 is a vertical sectional view taken along line
15-15 in Fig. 14.
_ 3 _
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DESCRIPTIO~I OF TIIE PREFEP~F.D ~,MBODI~NTS
Figures 1-10 are mainly clescriptive of a valve which
is particularly claimed in Canadian application Serial No.
227,203 referred to above. It is useful, however, to include
herein a description of the valve as claimed therein in order
to fully appreciate the valve of the present invention.
Looking first at Figs. 1 and 3, the servo-actuated
valve unit 10 of the present invention comprises water valve
12 and a vacuum servo 14. Valve 12 and servo 14 are mounted
on a right angle metal bracket 16. As will be seen in greater
detail hereinafter, the horizontal portion of bracket 16 forms
a cover 16a for valve 12, and the vertical portion of bracket
16, a mounting flange 16b for mounting servo 14.
'.
The details of valve 12 are best shown in Eigs. 2,
4 and 5. Referring in particular to Fig. 2, valve 12 comprises
a one-piece plastic valve body 18 having a generally
cylindrical side wall 2Q ~
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enc]osed at i~s ]ow~r axial encL by a ~o-ttonl wall 22. The upper
i~l end oE side wa].l 20 is diametrically enlarged to form a
shoulclcx 24 whi~ch extends continuously around the outside of wall
20 at a level ~low the circular upper end surface 26 of side wall
20, ~ide walls 20 define a gcncrally cyllndrical bore 28 which
extends upwaxdly from bot~om wall 22 to an internal snoulder 30
~h~ch is formed by a counter bore 32 in -the open upper end of
~s,ide wall 20, Cover 16a covers the open upper end of side wall
20, and four depending legs 34 (Fig. 3) are struck out of cover
16a to mount body 18 thereon. Legs 34 are circularly arranged 90
degrees apart around cover 16a and extend axially downwarclly over
the diametrically enlarged portion of side wall 20 and are turned
~adial~ inwardly around shoulder 24. A pair of small circular
pins 36 on diametrically opposite portions of end surface 2~ extend
through corresponding holes 38 in cover 16a. Pins 36 serve both
t~ properly locate cover 16a on body 18 during assembly and also
,
' to p~event cover 16a from being rotated on body 18 after assembly.
Body 18 further includes à patr of al.~gned generally tubular
ni,pples 40 and 42 which extend radially outwardly of side wall
' 20 2Q on d~a~etrically opposite sides thereof. Nipples 40 and 42
; h~ye'~enerally tubular bores 44 and 46 respec-tively which inter-
' cept bore 28 to form orifices 48 and 50 respectively. As can be
~seen in F~g. 4, oriices 48 and 50 subtend arcs of slightly less
- tha~ 60 degrees about the ax~s of bore 28,
For re~sons which will hereinater become apparent, the
preferable direction of flow through the valve is illustrated by
i, the arrows 52. ~ccord~ngly~ in the ensuing description, nipples 40
s~ ~nd 42 ~ill be refe~red to as inlet and outlet nipples, respectively, '~,
,' 29 ~nd orifices 48 and 50 as inlet and outlet orifices, xespectively. '' ~`
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UIlit 10 may be installed in ~he tleater circuit oE an automobile
by inserting hoses, such ~s shown in broken lines at 54 and 56 in
Fiy. 2, over the beaded ends of nipples 40 and 42, respectively,
and clampiny them on the nipples by suitable hose clamps 58 and 60.
Because o~ tlle light-weight construction of -the unit, it may be
wholly supported by the ~oses if desired.
Body 18 further includes an upright, generally cylindri-
cal post 62 which is co-axial with bore 28 and counter bore 32,
but does not extend the full length of bore 28. ~n annular depress~
10 ion 64 is fashioned in bottom wall 22 arouncl the base of post 62 hav-
i~g ~ diameter less than the diameter of bore 28 so that an internal
radial ledge 66 is formed around the bottom of bore 28. As shown
only in Fig. 4, body 18 ~lso includes four axial ribs 68, 70, 72
and ~74 w~ich are circumferentially spaced about side wall 20 of
,bo~e 28. Ribs 68 and 70 are located on opposi-te sides of inlet
orifice 48, being slightly circumferentially spaced therefrom.
Like~ise ~ibs 72 and 74 are located on either side of outlet ori-
~ce S0 and are similarly slightly circumferentially spaced there-
fro~. All four rxbs extend upwardly from ledge 66 to a level sor.le-
2Q ~a,t yertically aboye ti~e uppermost portion of the edges of ori- ~,
f~ces 48 and 50. ~hile the upper terminus oE the ribs is not
readily apparent from the drawIngs, its location will be readily ,~,
~nderstood from subsequent description of the internal ~alve
mechanism. From the foreyoiny description, it will be remembered , ~;
that body 18 is ~ one-piece plastic u-nit. Accordingly, in manu~
~acturing body 18, certain draft angles are often required in order
to form certain structural features of the body. ~hile certain o~ '
the above-described structural features of body 18 'nave been des-
2~ cri~ed as'being generally cylindrical ~e.g. side ~7all 20, and po5t
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19
62) or generally tubular ~e.g. nipples 40, ~2), it will be appre-
ciated that such items may have some clraft and therefore, reference
to an item as belng generally cylindrical or generally tubular
is. intended to encompass a perfectly cylindrical or a perfec-tly
tubular structure, respectively, and normally encoun-tered devia-
-tions therefrom.
Turning now to the internal valve mechanism, a generally
cylindricalr hollow plastic valve spool 76 having a yenerally
cylindrical side wall 77 is disposed within bore 28 with at least
a portion of its lower circular edge 78 resting on ledge 66. The
axial dimension of spool 76 is slightly less than the a~ial dimen-
sion of ribs 68-74, but as can be seen in Fig. 2, the upper circular
edge 80`of spool 76 is also disposed at a level somewhat above the
uppermost portion of the edges of orifices 48 and 50. As shown in
Fig. 4, the diameter of the cylinder defined by the radially inner
surface~ of ribs 68-74 exceeds. the diameter of spool 76, so that
spool 76 can be displaced radially to a limited extent w.~thin
bore 28. A pair of aligned generally circular orifices 82 and 84
are formed in dîametricall.y opposite portions of side wall 77.
20 Ori~fices 82 and 84 are su~stan-tially the same slze as orifices 48
and 50.. ~ith ~alve 12 fully open as illustrated in the drawings,
orifices 82 and 84 are aligned with orifices 48 and 50 to :Eorm a .~
fluid passage through valve 12 between nipples 40 and 42. Orifices ~`-
82 and 84 subtend arcs oE slightly less than 60 degrees and there-
fore, the complementary solid portions 86 and 88 o~ side wall 77
which ~re adjacent orifices 82 and 84 subtend arcs of slightly
more than 120 degrees. To actuate valve 12 to the fully closed
position, spool 76 is rotated 90 degrees in the clockwise direction
29 as viewed in Fig. 4 (and in the counterclockwise direction as viewed
~b/ ~ 7 -
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in Fig. 1) to position wall portion 86 over orifice 48 and wall
portion 88 over orifice 50 and -thereby stop -the flow of fluid
throug~l the valve. As will be seen later in more detail, servo
14 actua-tes valve 12 between its fully open and fully closed posi--
tions.
One of the features of this valve is the seal which
prevents leakage through the valve when closed. This seal prefer-
ahly comprises a deformable, resilient sealing gasket 90 mounted
on the wall of bore 28 between ribs 72 and 7~ around outlet orifice
50. A central opening 92 is provided in yasket 90 in alignment
with orifice S0. In its free state ~shown in Fig. 8) gasket 9O is
a simple flat square piece of res;lient material of uniform thick-
nes~s having smooth faces and a hole in the center. Gasket 90, which
~ay be formed of a suitable elastomeric material, such as Buna-N
ru~ber~ is dimensioned so that when assembled to the wall of bore
28~ it ~its snugly hetween ribs 72 and 74 with its inner surface
d~sposed radially inwardly of ribs 72 and 74 so that it is in seal-
ing contact with side wall 77 of spool 76.
This sealing contact is maintained in all operative posi-
tions of the valve by means of a spring 94 disposed diametrically
Opposite gasket 90 between spool 76 and the wall of bore 28. Spring
94, which is preferably made from either phosphor bronze or stain-
less steel, is shown in its free state in Fig. 7. Spring 94
is a flat rec-tangular element having a central rectangular opening
96, Two opposite edges of sprlng 94 are flanged, as at 98 and 100, ~-
to form a pair of side elements 102 and 104 which are effectivel~
bridged by flat resilient spring blades 106 and 108. When spring
9~ is assembled into valve 12, side elements 102 and 104 extend
29 ~xi~ally of bore 28 and -the bot~om edge of blade 108 res-ts on ledge
~cb/
': - : : .: . :........ ., . ............ . . '~. ' . . . :
.- . -- :- . . . . .- .
- .
6~. Fl~nges 98 and 100 are circumferentially restrained by ribs
70 and 68 respectively and the overall spring dimensioned so that
opening 9~ does not restrict orifices 48 and 82. ~s best seen in
Fig. 4, spring blades 106 and 108 are resiliently stressed or
flexed between the ~Jall of bore 28 and the side of spool 76 to
resili.ently bias the spool into a sealing relationship with gasket
90. It will be noted tihat only a small segment at the middle of
each blade 106, 108 contacts side wall 77, blade 106 contacting side
~all 77 above orifice 82 and blade 108 below orifice 82. Since
spring 94 is circumferentially constrained by ribs 68 and 70 and
approximately angularly centered with respect to orifice 48, blades
106 and 108 exert forces which are directed substantially radially
o~ b~re 28 and directly toward gasket 90. Spool 77 is of an outside
diameter less th~n that of all adjacent parts of bore 28, including
t~e axial ribs, so that it may float radially with respect to the
bore.
Orifice 48 is preferably the inlet orifice so that inlet
essure will assist spring 9-4 in urging spool 76 toward orifice 50 ~ `
and against gasket 90 in a sealing rela-tionship therewith. With
2Q th~s arrangement, gasket q0 is continuously forcibly pressed bet-
ween spool 76 and the wall of bore 28, the float of the spool
fac~lita-ting optimum sealing engagement with gasket 30 at all times.
Accordingly, when yalve 12 is closed and orifice 50 is covered by
spool wall portion 88, gasket 90 has a continuous peripheral sealing -
contact with and between wall portion 88 and the wall of bore 28 .
around orifice 50, which prevents fluid from leaking through the
yalye from inlet nipple 40 to outlet nipple 42. Because of the
constant bias of spring 94, the excellent sealing ability of this
29 yalve is maintained over a long life throughou-t the range of ~.
Cl}~/ _ 9 _
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~0~7C~g
temperature extrem~s to which the valve is typic~lly subjected
when in automotive use, and in such applications the seal is highly
i~mune to contaminants, such as antl-freeæe, cast iron particles,
core dus-t, oil, rust, sealer and the like.
Spool 7G is provided with a plurality of axial splines
107 (Flg. 2) on the upper inner surface of side wall 77. Splines
107 ex-tend downwardly from upper end surface 80 to an annular shelf
10~ which ex-tends around -the inner surface of side wall 77 just
ab~ye orifices 82 and 8~. ~s will be la-ter seen, splines 107
operatively connect spool 76 with the spool actuating mechanism.
Spool 76 and spring 9~ are axially retained within bore
28 by means of a cup-shaped plastic spacer 110 whose bottom end wall
112 rests on the upper ends of ribs 68-74 and also overlaps the
upper end surface 80 of spool 76 and the upper edge of spring blade
106. Spacer ~10 fits closely within bare 28 and the upper circular ~;~
end surface 11~ of spacer 110 is substantially flusil with shoulder
30. A deformable, resilient annular sealing gaske-t 116 overlies
spacer 110 ~ith the outer peripleral margin of the gasket over-
lapping both end surface 114 of spacer 110 and shoulder 30. The ~:
~uter diameter of gasket 116 is slightly less than the diameter of : -
counter bore 32 and gaske-t 116 is retained by an overlying metal
w~asher 118. Washer 118 fits closely within counter bore 32 and
ha~ a short down-turned peripheral flange 120 which circumferen-tially :~
encompasses the outer peripheral edge of gasket~ll6. The thickness
of the outer peripheral margin of ~asket 116 is sufficiently great
and the axial dimension of flange 120 sufficiently small relative
to the axial dimension between edge 26 and shoulder 30 that with
cover 16a mounted on the valve body, -the outer peripheral margin ;~
29 of gaske-t 116 is deformed into a continuous peripheral sealing .
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encJagemc-~nt with and arou~ld shoulcler 30 arl~l spacer 110 is urcJe(l
downt~arclly ayaills~ the upper ends of ri~s 68-74. Thus~ spacer
110 axially captures spool 76 and spring 94. ~]owever, the axial
di,mension of spool 76 is sligh~ly less ~han the axial dimension
o~ xibs 68-74 so that spool 76 will have a limited amount of axial
movementl to avoid binding and provide float beneficial to sealiny.
It will also be observed that washer 118 completely covers the open-
ings 122 which remain in cover 16a after legs 34 are struck from
the cover so that the possibility of gasket material being extruded
through openings 122 is substantially eliminated.
The actuating mechanism for spool 76 is best described
with reference to Figs. 2 and 5. Looking first at Fig. 2, a shaEt
126 is-journalled for rotation ~ithin bore 28 by a cylindrica]. axial ,,,,,~
bore 134 in its lower end. Bore 134 supports and journals shaft
126 on the upper en~ of post 62, which is preferably approxima-tely '
ci,rcular to provide a suitable bearing surface. The other énd of
shaft 126 includes a slightly diametrically reduced circular portion ~ '
138 for journalling the shaft within a circular hole 136 in cover
16a. Shaft 126 extends through a suitable clearance hole 140 in
20 washer 118 and has a cylindrical wall portion 142 below washer 118.
The inner periphery 146 of gasket 116 is sealed against wall 142-~
by means of an axially extending annular sealing lip 144, the inner
~eriphery 146 of which is preferably slightly less in its free
~tate than the diameter of wall 142. Lip 144 is held in continuous
peripheral contact around the shaft by means of a garter spring 148
disposed over and axound the outer periphery of lip 144. This arrange-
ment proYides a ~luid~tight seal around sha~t,126 for all rotary
opera~ing positions o~ the shaft~ The lower portion l.S0 of shaft ,~
29 ~26~ which is generally coextensive with bore 134, has a transverse
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cross sectiQn pol.~gonal in shape. This polygonal portion 1~0 keys
shaft 126 to a thimble-shaped coupling 152. Portion 150 ex-tends
through a mating polygonal .hole 154 i.n the top end wall of coupling
152 to connec-t coupling 152 ~or rotation with shaft lZ6, while
proyidin~ an axial lost-mo-tion connection so that coupling 152
can ~ove axially oE shaft 126. Coupliny 152 extends through a
Suitable opening 156 in bottom wall 112 oE spacer 110, and rests on
shelf 10.9 of spool 76. An outwardly turned radial flange at the
bottom of coupling 152 is fashioned with a plurality of radial
teeth 158 which mesh with splines 107 on spool 76. This opera-
ti~ve connection is shown in greater detail in Fig. 5 and permits
lo~st motion between the spool and shaft assembly. It will be
observed in Fig. 2 that upward axial movement of coupling 152 is
lim~ited by a shouldèr 130 on shaft 126 and that splines 107 are
.of sufficient length to remain meshed with teeth 158 over the normal
range of relative axial movement between coupling 152 and spool 76.
The lost motion connection between shaft 126 and spool 76 essen~
tially eliminates radial and axial loading on the spool and per- ::~
mits the float beneficial to sealing. The double journal of shaft :
126 eliminates, or at least minimizes, shaft wobble and essentially -
precludes the possibility of shaft binding or bending when the
yalye is actuated.
An opening lever, or crank, 160 for rotati.ng shaft 126 .
is at-tached to the external end of shaft 126 by a screw 128. qlhe
radially outer half o$ lever 160 is spaced somewhat above cover
16a by an intermediate bend 162 and a circular hole 164 is pro~
yided near the radlally outer end of the leyer for operatively
connPc~in~ the leYer with servo 14. With this arranyement, when
29 lever 160 is operated in the coun-terclockwise d.irectlon in Fig. 1
., .
cb/ - 12 -
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from its sol;d line pOsit.ic~ll to i.ts broken l]nc position, spool 76 is
rotatcd 90 degrees in ~he clockwise directlon in I~`lg. 4 ~rom the
illustrated full~ open position to the fully closed position (not
illus~rated). Counterclockwise ro-tation of l.ever 160 in Fig. 1
is limited by a stop lG6 which is s-truck upwardly out of cover 16a.
Turning now -to Figs. 1 and 3, seryo 1~ has a two-piece gen-
erall~ cylindrical body 168 comprising a plastic shell 170 and a metal
shell 172. Servo 14is mounted on bracket 16 with the end wall 174 o~
shell 172 against flange ].6b, Three retaining tabs 177 are struck
out of end wall 174 around the periphery of an opening 176 in the wall ~ :
for retaining servo 14 on bracket 16. The internal struc-ture of seryo ,.
14, best shown in Fig. 3, includes a movable annular diaphragm 178,
the outer periphery of which is securely anchored and sealed between ~ ,
shells 170 and 172 to divide body 168.into an atmospheric chamber 180
and a vacuum chamber 182. Chamber 180 co~nunicates with ~tmospher~ .
Yia opening 176 while chamber 182 communicates ~ith a source of ~,'
vacuum via a tubular nipple 185 integrally formed with shell liO. ~ :
Nipple 185 is protected by a shield 185a which partially surrounds same.
As will be described in greater detail hereinafter, ,~
diaphragm 178 is moYable axially of body 168 in response to the pre~
ssure of a vacuum in chaI~er 182 relative to atmospheric pressure
and comprises,a circumferent;ally continuous, deformable, resilient
outer peripheral bead 184, which has a generall~ circular cross
section when in its free state (Fig. 9). An oYerhanging, cir-
cumferentially continuous lip'l86 e,xtends around the outside of
side wall 188 of shell 170 just below the open upper end of the .'
shell. Lip 186 comprise~ a radially extending upper surface 190
which is spaced radially outwardly of and ax~ally below the upper
29 end surface 192 of side wall 188.An inclined surface 194 ext,ends
cb/ ~ 13 ~
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around tllC? shell b~tween the radially outer edge of surface 192 and
the ~adially inner edcfe o~ surface 190. Lip 186 further comprises
an axially extending side surface 196 which ex-tends downwardly from
-the raclially outer edge of surface 190. A convex surface 198 extends
inwardly Ero~ the bottom edye of side surface 196 to the radially
ou-ter edcJe of a concave sur.Eace 200~ The radially inner edge of
concave surface.200 is connec-ted to side ~rall 18g. Metal shell .
172 has a circumferentially con-tinuous radial flange 202 which
is generally radially co-extensive wi~h surfaces 192 and 194 and
the radially inner portion of surface 190. A circumferentially .
continuous curved bend 20~ at the radially outer edge of flange
202 connects a circum~erentially continuous axial flange 206 to
flange 202. The inside diameter of shell 172 across flange 206
is slightly greater than the diameter of lip 186 across side sur- ~ -
face 196. Flange 236 extends axially fully over lip 18~, and
a circumferentially continuous curled flange 2Q8 on the lower edge
of flange 206 is wrapped inwardly around lip surface 198 to inter-
lock the shells. ~end 204 and the immediately contiguous portions
of flan~es 202 and 206 cooperate with lip surfaces 130 and 194 to .
form a continuous peripheral recess 210 around body 168 between
the two shells. Bead 184 is deformably held within recess 210 to
enseal the outer periphery of diaphragm 178 with shell 170.
It will be appreciated that preparatory to assem.bling the
two shells, flange 208 is essentially a continuation of flange 206.
The shells are interloc~ed by first inserting -the open end of shell
172 over the open end of shell 170 until the peripheral margin of
diaphragm 178 jus-t inwardly of bead 184 is forcibly interengaged
between flange 202 and end surface 192, with bead l8~ being defo~m-
29 ably held within recess 210. Flange 208 is then rolled or spun
..,
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over lip 186 and wrapped around lip surface 198. ~fter assembly
of the shells, it will ~e observed that lip 186 has deformed bead
184 from its initial circular shape as defined in part by the ~',
bro~en line 212, More specifically, lip surface 194 has bodily
dis,placed the portion of be~d 18~ lden-tified by the numeral 213
so that bead 184 deforms to the illustrated shape. It will be
obseryed that the cross sectional area of recess 210 exceeds -the
cross sectional area of bead 184 so that suitabl'e space is pro-
yi~ded ~ithin recess 210 to accommodate the deformation of bead
10 184, accoùnting for var~ations in normal manufacturing tolerances. :~
As a result, the deformed bead 184 has a circumferentially contin- ~
uous sealing contact around and with the open end of shell 170 to ~:
provide a fluid-tight outer peripheral seal for diap'nragm 178
with shell 170. sead 184 is dimensioned to maintain this sealing .~
engagement in the event of any spring-back in flange 208 which .. : .
mlght allow the deformed bead 184 -to slightly relax and thereby :'
cause some axial separation of the shells. Furthermore, because
o,f, tl~e wrap-around relationship of metal shell 172 over plastic
shell 170, the strength.of the metal shell is imparted to the
plastic shell thus minimizIng distortion of the assembly under
the influence of high pressure differentials and high temperatures..
The central region of diaphragm 178 is held between a
metal aiaphragm washer 214 and a metal diaphraym cup 216 by means
of a rivet 218, as best shown in Fig. 6. ~Jasher 214 is generally
flat haying a small circular hole 220 at its center and the gener-
ally flat end wall 222 of cup 216 is of approximately the same
diameter as washer 214. ~ small circular dimple 226 is formecl
at the center of wall 222 and a small circular hole 228 extends
29 through the dimple. The circular inner periphery 230 of diaphra4m .
cb/ - 15 -
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.
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lL~47~9
178 is alicJned with holes 220 and 228 and the shank 232 of rivet
218 passes tllrough the three holes 220, 228 and 230. Diaphragm
178r ~c~sher 214 and c~lp 216 Rre held together b~ mecans of a shoulder
238 and ~ deformed, enlaryed end portion 239 on rivet 218. A
de~ormc~ble resilient bead 234 extends continuously around the
~nner periphery of di~phragm 118. DiMple 226 cooperates with the
oyerl~ing ~ortion of w~sher 214 to form an annular recess 236
araund rivet 218. The sandwiched retention o diaphragm 178 bet-
~een washer 214 and cup 216 by means of rivet 218 causes bead 234
t~ be deformably contained within recess 236 to enseal the inner
periphery of diaphragm 178 with rivet 218. With bead 234 so
held, it will be observed in Fig. 6 that dimple 226 has deformed
bead 234 from its free cross sectional shape as defined in part by
b~oken line 237. More specifically, the portion of bead 234 identi-
fi~ed by the numeral 235 has been bodily displaced with the resulting
displacement thereof tending to force bead materlal radiall~ inwardly
a~ound shank 232. The cross sectional area of recess 236 exceeds
the cross sectional area of bead 234 so that suitable space is pro-
y~ded ~ithin recess 236 to permit the bead to deform to the`shape !~
~llustrated~ as in the case of ~ead 184. Thus, the inner perlphery
230 o~ dtaphragm 178 does not buckle or otherw~se uncontrollably
compreSS upon assembly of washer 214 and cup 216 to the diaphragm
but rather deforms into a circumferentially continuous sealing
contact around and with shank 218 to provide a fluid-tlght inner
peripheral seal for diaphragm 178.
A connecting rod 240 operativel~ c~nnects diaphragm 178
~th lever 160. The near end of rod 240 has a right-angled flange
242 qttached to diaphragm 178 by rivet 218. ~ circular hole 244
29 ~i~n ~lange 242 flts around rivet 218 and is retained by the rivet
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head 246. The a-t-tachmen-t is just loose enough so that rod 240 can
rotate on rivet 2l8, such rotation being required to permit ro~ 240
to be p.roperly oriented for connection to valve 12. The other end
of rod 24Q is interloc~ed wi-th lever 160 by means of a down-turned
-tab 248. Tab 2~ comprises an intermedia-te tab portion 250 di.s-
posed ~ithin hole 164 of lever 160. Tab portion 250 has a rect-
angular transverse cross section, bes-t illustrated in E'ig. 10.
The major dimension, or length, of the cross section is substantially
greater than its minor dimension or width. Tab portion 250 is .
dimensioned to fit closely within hole 164, with the four edges
252,254, 256, 25~ of por-tion 250 being disposed just within the -
edge of hole 164, and is disposed on rod 240 such that the length
of its transverse cross section is substantially parallel to the
length of the rod. Since rod 240 moves generally lengthwise upon
operation of servo 14, the length of -the transverse cross section
of tab portion 250 is generally aligned with the direction of
moye~ent of rod 240. For a given dimension tab por-tion 250 and
giyen diameter hole 164, such orientation of ta~ portion 250 rela-
tiye to the direction of movement of rod 24Q provides minimum
free play and binding between rod 240 and lever 160 over the
arCuate path of travel of the lever.
Tab 248 terminates in a free end por-tion 260 disposed
beneath lever 160, and portion 260 interloc~s rod 240 to lever 160
so that a separate attaching part such as a rivet is not required.
Tab portion 260 comprises a projecting tip 262 disposed on the tab
radially outwardly of the edge of opening 164 when the rod is
connected to lever 160, and is fashioned as at 26A with sufficient
clearance so that tip 262 can be inserted into hole 164 and the rod ~ :
29 thereafter manlpula-ted to bring intermedia-te -tab portion 250 within
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opening 164. Before -this connection can be made, howeyer, leyer
160 must be operated to its broken line posi-tion in Fiy. 1. Servo
14 i$ then orlen~ed so tha-t rod 240 can be inserted throuyh an open-
in~ 270 in flange 16b at a downwardly inclined angle toward valve
12, This inclination permlts tlp 262 to be inserted through hole
164 and beneath lever 160. Servo 14 is then swung downwardly
about tab 248 with the clearance provided by the lower edge sur-
face o-E the tab at 264 permitting tab end portion 260 to pass
t~r~u~h hole 164 until the intermediate tab portion 250 lies within
th,e hole. Seryo 14 may then be attached to brac~et 16.
With seryo 14 operatively connected to valve 12 and both
seryo and yalve mounted on bracket 16, valve 12 is biased toward
the open position by a compression spring 272 within servo 14.
One end of spring 272 seats within the interior of cup 216 while
th~e other end'of the spring seats within a seat 274 formed in the ,~
bottom of shell 170. Spring 272 biases diaphragm 178,toward end
~wall 174 with the interen~agement of washer 214 and end wall 174
~seryin~ to limit the ax~ally outward movement of the diaphragm.
~hen Yacuum is introduced into chamber 182 Via nipple 185, the
20 ~eater pressure in atmospheric chamber 180 forces diaphragm 178
downwardly w;thin body 168 to compress spring 272 and cause rod
240 to rotate leyer 160 until the yalve is moved to its fulIy
closed position. Although diaphra~m 178 in this position com~
pleteIy coYers seat 274 around the lnternal shoulder 275 between
side wall 188 and seat 274, communication of vacuum chamber 182
I with,nipple 185 is ~aintained by a passage formed in shoulder 275.
¦ T~us, it is impossible for the diaphra~m to seal itself into an
,i,nope~ative position.
, 29 The present invention will now be described with refer-
',' ':'
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ence tu lii.gurcs 11 to 15 ancl wi~ll reference to thc back~Jround
~ate~ial proyi.ded b~ Flgures 1 to 10 and the descripti.on thereof.
It will be apprec.iated that tl~e present inventi.on is an alternative
and improved embodiment of the valve just described.
Except or those elements discussed below, the valve
.illustrated in Figs. 11 and 12 i.s subst~ntially identical with that
shown in Figs. 2 and 4, and therefore a detailed discussion of its
construction will not be repeated. Corresponding components of
t~e two e~bodimen~s are identified with like reference numerals,
e~cept for those elements which pertain exclusively to the second
embodiment, which are primed.
The valve shown in Fly. 11 comprises a body 18 prefer-
ably made of sheet metal. It has been found to be advantageous,
e~specially in automo.tive applications, to construct the valve out
O~ sheet metal rather than mold ~t out of plastic, as in the initial
embodiment, because sheet metal is more flexible in design than
molded plastic. Thus, the valve can more readily be manufactùred ~`~
~in yarious sizes and with.different fittings and hose arrangements,
~ith ~ubstantially; less tooling costs tllan if new molds were required.
As previously mentioned, one of the difficulties encounter-
ed ~in yalves of th~s type is the problem of internal leakage pre~ :
venting the valve from completely blocking fluid flow when closed,. . :-
es~ecially at low pressures. As disclosed in the first embodiment, .;~
t~i~s problem can be substantially eliminated by mounting a deform~
a~le, elastomeric sealtn~ gasket around the outlet oriflce, thereby ~:
~oxming ~ seal between the wall of the bore and the valve spool~
The ~ore readil~ deformable or softer the ma*erial used, the better
the seal at lower pressures. However, it has also been found that
29 the softer the gasket material, the more apt it is to extrude
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or move into the outlet orifice under high pressures. Thus, it
is the purpose oE the presen-t invention illustrated in ~iys. 11
to 15 to reconclle these competing interests and provide a valve
design which will permit the use of a sufficiently pliable seal- -
ing gasket to e-Efectively prevent leakage at low pressures, bu-t
w,~thout extruding at 'hig~er pressures.
This is accomplis~ed by designing the seallng gasket 90
in the manner illustrated in Figs. 11, 12, 14 and 15, the latter
t~wo Figures showing the gasket 90 in its relaxed state. ~eferring '~
to ~ig. 14, gasket ~0 ls generally annular in shape having its
inner diameter 92 equivalent to the diameter of outlet orifice 50.
Gaske-t 90 has substantially flat ou-tside and inside surfaces 95'
and 97', respectively, with the radial thickness of the gasket
greater at the outside surface 95' than at the inside surface 97'. ~-
Extending generally perpendicularly from surface 95' of
gasket 90 are a plurality of protrusions 91' circumferentially
spaced approximately equldistantly apart. For example, Flg. 14
s~D~ws gas~et 90 as having eight protrusions 91' spaced approximately
45~ apart. As will subsequently ~e explained in more detail,
protrusions 91' extending from gasket 90 serve to anchor the
~$ket in place.
The gasket 90 is mounted in the ~alve between spool 76
and the wall of bore 28, as described in connection with the des-
criptiOn of the initial embodiment, with protrusions 91' facing
away fro~ val~e spool 76. To accommodate protrusions 91' when the
g~sket 90 is assembled within the valve, a plurality of corres-
pQnding holes are similarly formed around the periphery of ou-tlet
ori,fice 50 in side'wall 20 of valve body 18. Thus, in the illus-
29 trati,ve embodiment shown, a corresponding set of eigh-t holes,
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also sp~ced ~ apa~t, is forllled i.rl wall 20. ~s best illustrated in
Flg. 12, the holes ormed ~out the out~ t oriice 50 are drilled per-
pendicular to tubular side wall 20 of valve ~ody 18 so that protrus-
ions 91' will snugly fit within -the holes when the seali.ny gasket 90
is forced against the wall of bore 28. ~s can reaclily be seen, with
protrusions 91' extendin~ through wall 20, preferably with each hav-
ing an unstressed diameter slightly greater than the diameter of the
corresponding hole in the valve body, sealing gaske-t 90 is more rigidly
secured than in the precediny embodiment, and therefore is subs-tant-
ially less apt to extrude or move into the outlet orifice 50, even
under high ~luid pressures. This in turn permits the gasket 90 to
be made of a relatiyely soft elastomeric material (preferably 50-60
durometer) so that a proper seal at low fluid pressures will be form-
ed between spool 76 and ~asket 90, and between gasket 90 and the wall
o~ bore 28. In addition, gasket 90 is less likely to rotate with
the spool 76 due to frlction when the valve is opened and closed.
The cross-sectional shape of gasket 90 also contributes
to its function. As seen in ~ig. 15, the radial thickness of
gasket 90 at its inner surface 97', indicated at 101', is pur : -
posefully less than that of its outer surface 95' so that excess- .
ive friction is not created between surface 97' and valye spool 76
when the latter is rotated. However, it should also be noted
that this radial thickness cannot be made too small or the gasket
may "roll" over when Yalve spool 76 is rotated. Also, the outer
ci~Gumferential edge of ~as~et 90 has a generally cylindrical por-
ti~n 103' adjacent surface 97~, which acts as a scraper to prevent
,
any debris which may accumulate between spo~l 76 and the ~all of
bore 28 from becoming lodged between spool 76 and gasket 90
29 when the spool is rotated. ~ny ~oreign matter which should work
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its way bet~een -the gasket a~cl spool could de-trimentally effect
the seal formed and as a resul-t hamp~ the proper functioning of
the valve. Also of 5tgnificance is the uns~ressed -thickness of
the gasket, indicated at 99'. It should be large enough to accommo-
date manufac-turing tolerances and remain stressed (compressed) in
all rotative positions of the valve, to maintain an effective seal,
but no so large that unnecessary friction or a tendency to roll
over is created.
Referring again to Fig. 12, it will be noted that body
18 does not contain the four axial ribs 68, 70, 72 and 74 present
in the first embodiment. This is primarily due to the change in
body material from molded plastic to sheet me~al. Since the ~unc-
tion of ribs 72 and 74 in the first embodiment is to maintain valve
spring 94 in its proper pOSitiOII diametrically opposite sealing
~asket 90, alternative securlng means in the second embodiment
is required. For this purpose, any method which will prevent
valve spring 94 from moving when the spool 76 is rotated may be
employed. One such method is shown in Fig. 13 which illustrates
a modified version of valve spring 94 depicted in Fig. 7.-
Valve spring 94 shown in Fig. 13, is a flat rec-tangular
member having a central rectangular opening 96 defined by a pair
of side elements 98 and 100, bridged by flat resilient side elements
106 and 108. Extending inwardly into central opening 96 from
side eIements 98 and 100 are appendages 105' and 107'. The func-
tion of these appendages lQ5' and 107' is best illustrated in
Fig. 12. When spring 94 is assembled into -the valve diametrically
opposite the gasket 90, between spool 76 and the ~7all of bore 28,
appendages 105' and 107' ex-tend into inle-t orifice ~8 and engage
29 the sides of the opening in the manner shown. In this manner,
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va].ve spring 9~ prevented froln ~hiftiny when the spool 76
is rotated.
Also disclosed in this embodimellt is an ~lternative drive
~echanism for ro~atiny ~alve element 76 hetween its open and closed
positions Again, this modification is prompted h~ the change from
~olded.plastic to sheet ~etal used to construct the valve~
Referriny to ~i.g. 11, valvc body 18 has a central de-
~ression 6~ fashloned in its bo-ttom wall 22, defining an internal
~adial ledye 66 around the bottom of bore 28. The actuating mechan-
ism comp.rises a main shaft 62 co-axial with bore 28 which extends
the entire leny-th of bore 28. The upper seyment 63' of shaft 62
has a hexagonal shaped cross-section, below.which shaft 62 grad-
ually tapers to a cylindrically shaped bottom segment 65'. The ~ :
bottonl segment 65' o~ shaft 62 extends below the bottom of bore `:~
28 as defined by ledge 66 and terminates in depression 64. Dis- ~.
posed on ledge 66 is a gu~de ~ember 69' which secures the lower
portion of sh.aft 62 against radial movement relative to its axis.
Guide 69' consists of a flat element ha.ving an annular shaped
central portion 73' with a plurality of integral legs 71' radially
extending therefrom. For example, the preferred embodiment depicts
~uide 69' as having three legs 71' circumferentially spaced 120
apart, Legs 71' rest on ledge 66 and extend to the wall of bore 28
~he~e the~ flange upwardly, as shown at 75'. The diameter of the
center hole 67' in guide member 69' is slightlv larger than the
d~ameter of the bottam segment 65' of shaft 62. Thus, with guide
69! disposed on ledge 66, sha$t 62 fits th~ough center hole 6~'
~nd is free to rotate about its axis, but is prevented from moving
in a xadial direction out of coaxial aliynment with bore 28.
29 Spool 76 fits down into bore 28 around shaft 62 until
cb/ - 23
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the bottom ed~Je o~ its cy:l,i.l)clrical wall xests on lecJs 7l' of
guide 69', ~lso ~ ted aroulld ~he he~.lgonal seyment 63' of
sha$t 62 is a die cast driver memhcr 79' having a hexagonal shaped
center ~ore which m~tes wi.th shaft 62 as shown. Driver 79' has
a plurality o~ circum~erential.ly spaced spl,ines ~l' which mesh
wlth a pl.urality oE invol.uted tecth 77' circum~erentially spaced
on spool 26. To insure that teeth 77' of spool 26 remain meshed
~it~ splines Sl' of driver 79', driver 79' is fashioned with a
shoulder 83' wh,ich overlaps teeth 77', thus preventing driver 79'
from sliding down shaft 62. Furthermore, to prevent driver 73'
f,rom ~Oying out of alignment with spool 26 in the opposite dir-
ection (such as when the valve is mounted upside down) a spacer 8S'
is proyided which fits on shaft 62 above driver 79' as shown.
Note that the axial length of splines 81' is greàter than the
distance between spacer 85' and shoulder 83' of driver 79'. In
thiS manner, the maximum amount of axial movement permitted between
driyer 79' and spool 26 relative to shaft 62'is insufficient to
cause the unmeshing of the spline dri've unit. ~s with the first ' ~ .
e~bodiment, this lost motion connection betwéen shaft 62 and spool
76 el~minates radial and axial loading on the spool and permits
~he float characteristic beneficial to sealing.
The construction of the remainder'of the second embodi- ~.
,ment of the valve, as well as its operation, remains the same as
thRt previously described in connection with the first embodiment.
The advanta~es of the servo-actuated valve unit lO of
thQ ~resent invention are particularly apparent when the unit is
ut~lized in connection wi~h an au~omotive heater system wherein
the flow of coolant through valve 12 is controlled by a vacuum
2q contxol signal supplied to servo l~. Due to the light weight o~
-~b/ - 24 -
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the unit, it rnay be possible ~o elimina-tc the u5ual at-tachiny
bracke~ and sinlply support ~he unit on hoses 54 and 56. Because
y~cuum chamber 182 is so ~ell sealed, servo 1~ develops maximum
com~essive force agains~ spring 272 for a given intensi,ty of
ya,cuu~ signal. The reliable internal valve seal not only assures
that tllere will be no leakage through the valve when the valve
i~s closed, the bias developed by sprinc3 94 forcibly pressing the
~ske-t 90 between spool 76 and the wall of the bore, but also ~;
does not hinder the operation of the spool be-tween opened and
closed positions~ The floating capability of spool 76 and the bias
of spring 94 assures continuous fluid-tight seallng engagement of
~asket 90 between the spool and the valve body even as the parts
w~ear, ~ccordingly, the valve is intended to provide a long trouble-
~ree l~fe even under adverse conditions. While possessing the al-
~eady enumerated as well as other advantages, the preferred embodi-
mentS moreover exhibit an economy of construction which render
them ide~lly suited for mass production.
Thus, -there'~s disclosed in the above description and in
t~e drawlngs embodiments of the invention which fully and effectively ~'
a,ccomplish the objects thereof. ~Iowever, it will be apparent that
ya~ations in the method may be indulged in without departing from
the sphexe of the invention herein described, or the scope of the
~ppended claims.
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