Note: Descriptions are shown in the official language in which they were submitted.
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BACKGROUND OF THE INVENTION
Substantial effort has here~ofore been expended in
development of rotary valve apparatus for in~ernal combustion
engines. This effort is warran~ed because of the basic inef-
ficiency of the conventional type of reciprocatin~ ~al~es that
~ have been almost exclusively utilized for such engines. The
; reciprocating type of valve subs~antially interferes wi~h gas
flow in that the valve head is always disposed in the path of
the gases Tesulting in flow-path distortion that materially
reduces and restricts the gas -flow into or out of a cylinder~
Purthermore, mechanical actuation o reciprocating val~es repre-
sents an additional energy loss in view of the numerous compo-
nents that are necessary for operation. While a cam in head
engine eliminates the push rods that are otherwise required~ the
cam mechanism does include levers and springs for maintaining the
valves in a closed position. The levers and springs re~uire ex-
penditure of a certain amount of energy for operation wh~ch
further reduces engine efficiency.
Rota~y valve mechanisms known to have been de~Jeloped
for inteTnal combustion engines has either comprised elongated
tubes that connec~ with several cylinders or disc-type valve
elements disposed in each cylinder. Neither of these two types
of rotary valve mechanisms have been found to be as effective
or as efficient as desired or possessing sufficient advantages
over the reciprocating valves.
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1 SUMMARY OF T~IE INVENTI0~
The rotary v~lve apparatus of this invention comprises
independent valve elements for both intaXe and exhaust paIts of
each cylinder ~ith each valve elemen~ disposed in its o~n chamber.
Each valve element comprises a cylindrical shell that is open at
one end and has a port formed in the cylindrical wall. A port is
also formed in each valve chamber and which communicates with the
respective engine cylinder. Rotation o~ the valve results in
periodic al~gnment of the valve part with the cylinde~ part thus
permitting gas 10w therethrough, either intake or exhaus~, in
timed relationship with piston movement. All inta~e valve elements
are mounted on a common drive shaft for concurrent revolving of
all intake valves. Similarly, all exhaust valve elemen~s are
mounted on their own common drive shaf~ for revolution indepen-
dent o but in timed relationship to the intake valves.
Separate cylindrical valve chambers are ormed in ~he
engine head fo-r each valve element, both intake and exhaust~ In
addition ~o the previously mentioned ports communtîcatl~g with
~he engine cylinders, each valve chamber is provided with a
respective port communicating with the induction system or the
exhaust system. Thîs providing of separate ~alve shambers
results in an advantageous isolation of the valve elements and
an adjacent portion o~ the associated induction or exhaust system
for more efficient engine operation.
Separate drive sha~ts for the intake and exhaust valves
also permits selective ~djustment of timed relationship between
the intake and exhaus~ val~es. This adjustability enables opera-
72~5
Docket 9756-3
1 tion of an engine over a substantially greater speed range
than would otherwise be possible.
According to one broad aspect of this invention,
there is provided a rotary valve apparatus for an internal
combustion engine comprising a cylinder head or an engine
which includes at least one cylinder with the cylinder head
adapted for mounting on the engine in operative relationship
to ~he cylinder, said cylinder head having formed therein an
intake valve chamber and an exhaust valve chamber, each of
said chambers being of elongated cylindrical configuration,
valve ports providing fluid communication between respective
: valve chambers and the engine cylinder and an intake port and
an exhaust port providing fluid communication between a re-
spective valve chamber and a respective inta~e or exhaust
manifold, and a rotary valve element of elongated cylindrical
configuration coaxially disposed in each of said valve chambers
for revolving movement in fluid flow controlling relationship
to the respective valve port, each rotary valve element in-
cluding a cylindrical tube mounted on a respective rotatable
drive shaft journalled in said cylinder head and having an
open end in fluid communication with either the respective
intake or exhaust port and an aperture formed in a cylindrical
wall thereof at a position to align with the respective valve
port for a predetermined time interval during each revolution
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Docket 9756-3
1 of said rotary valve element and permit fluid flow there-
through, each of said valve chambers being of a length to
extend a distance axially from the open end of the valve
element, said intake or exhaust port communicating with the
respective chamber extension.
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DETAILED DESCRIPTION OF T:HE ILLUSTRATIVE
Ei'il~ODI~ NT
,
A cylinder head 10 is shown in Figure l for an internal
comhustion engine having two cylinders with this head being fabri-
cated in t-~o sec~ions 11 and 12 which are designated ~ower and
upper sections respectively. Both sections are adapted to inter-
fit in superposed relationship and to be secured ~o the top of
a cylinder block 13 for an internal combustion engine by means
of bol~s 14 as shown in Figure 4. The illus~rative embodiment
is a two cylindeT engine b~t it will be understood ~hat the
number o~ cylinders may be increased and that the rotary valve
apparatus may also be readily adapted ~o a V-block engine.
.
Formed in the two sections of ~he cylinder head are
the respec*ive mating halves of the valve chambers lS and 16,
intake and exhaust, respectively. These valve chambers are
elongated cylinders wi~h all of the intake chambers disposed
in axially aligned relationship as are the ~xhaust chambers. It
will also be noted that the longitudinally aligned sets of cham-
bers 15 and 16 are la~erally spaced apart in parallel relation-
ship with the space ~herebetween providing a place -for receiving
an ignition plug 17 as shown in Figure 4. The base of khe igni-
*ion plug 17 projects through an aperture 18 provided in the
upper head section 12 and is threaded into a soc~et 19 ormed
in the lower head sec~ion 11 ~ith the electrodes 17a of the ig-
nition plug extending into a head chamber 20 formed in ~he lower
surface of the lower head section 11.
Each o the intake and exhaust valve chambers 15 and 16
is ~ormed with a coaxîal extens;on, lSa and 16a, respecti~ely.
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~0 7 Z ~ ~
1 These coaxial extensions as ~ill be subsequen~ly described in
greater detall relative to a discussion of gas flo~r into or out
of the valve chambers. The main portion of each val~-e chamber 15
and 16 25 previously stated is an elongated cylinder o~ predeter-
mined length and diameter to receive a respective valve elementto be described hereinafteT. The chamber extensions are also o~
elongated, cylindrical configuration but the diameter thereof
immediately adjacent the respective main chamber is o~ slightly
smaller diame~er with ~he remote end portion being arcuately
configured.
The lower s~t~on 11 of the cylinder head is also pro-
vided with valve ports 21 in the respective valve chambers 15 and
16 and which communicate with a cylinder 22 in the cylinder
block 13. A reciprocating piston P is included in the cylinder
22 for ope~ation in a conventional manner. The valve ports 21
are of the illustrated elongated rectangle configuration extend-
ing circumferentially rela~ive ~o the cylindrical surface of the
valve chamber in alignment with the ignition plug socket 19. This
places the ralve ports 21 in diametrically disposea relationship
to the associated cylinder for optimum uniformity in gas flow
during the cyclic operation of the engine.
Formed in the upper section 12 of the cylinder head are
intake and exhaust ports 23 and 24, respectively. These ports
open to the respective valve chamber extensions 15a and 16a and
are longituainally displaced in offset relationship to the valve
ports Zl. Mounting bosses 25 with threaded bolt holes 26 are
formed on the exterior surface of the upper head section 12
30 around the periphery of the intake and exhaust ports 24 and 25
.... .. ..
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1 to ~acilitate connec~ion of induction and exhaust conduits
~not sho~
Posi~ioned in each of the valve chambers 15 and 16
is a rotary valve element 27 with all intake valves secured on
a common drive shaft 28 and all exhaust valves secured on a
second common drive shaft 29. ~ach drive shaft 28~ Z9 is jour-
nalled in bearings 30 with each shaft having a respective end
portion 28a, 29a extending through an end wall 31 of the cylinder
head 10. The bearings 30 are disposed in respective be~ring
seats formed in ~he upper and lower head sections 11 and 12
Mounted on each end portion 28a and 29a, respectively~ is a
valve drive gear 32, 33. A driving mechanism tnot sho~m) is
connected to the gears 32 and 33 and this ~echanism may advan-
tageously be o a ~ype which permits selective adjustme~t ofthe valve timing relative to the crankshat ~piston position)
and selective relative adjustment of the intake and exhaust
valve timing. Mechanism for effecting such selective adjustmen~
is well known in the a~t and,,,therefore, is not shown in the
drawings as it is not ~ecessary or an understanding of this
invention.
As can be best seen in Figures 2 and 3~ the ro~ary
valve elements 27 comprise a cylindrical ~ube 35 ~hat is open
at one end and is integrally formed wi~h an annular moun~ing
hub 36. The hub 36 closes the one end of the cylindrical tube
35 and includes a coaxial bore 37 through which the respective
shafts, 28 or 29, and on which the ~alve elements are faxed in
driving relationship. A suitable driving relationship may be
efectively obtained by a key 38 adapted ~o fi-t in~o a recess
(not sho~m) formed in the shaft and interengaging with an axial
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1~7245~
1 slot 39 in the bore 37. It will be noted that the thickness
of the cylindrical t-lbe is such that ~he internal surface thereof
is contiguous wl~h the chamber axial ex~ensions 15a and 16a for
better fluid flow.
An aperture 41 of rectangular shape is formed in the
wall of the cylindrical tube 35 of each valve element 27. This
aperture 41 is of predetermined lsngth and is of a wid~h and
length commensurate with the width and length of the respective
valve ports 21 formed in the valve chambers. The apertures ~1
are axially posi~ioned in the cylindrical tubes 35 such that wi~h
the valve elemen~s positioned in a respective valve chamb~r~ 15
or 16, the apertures will align with the valve ports to permit
gas flow into or out of the cylinder by means of ~he open end
of the cylindrical ~ube and coincident aper~ure and valve port.
The specific lengths of the valve ports 21 and apertures 41 aTe
determined by the particular engine performance charac~eris~ics
that are desi~ed with due regard to overlap a~d open-port times.
~0 Effecti~e fluid-~ight sealing o~ the rotary ~alve
elements 27 in their respective chambers 15 or 16 is achieved
by means of resilien~ sealing elements. These sealing elements
are abricatea from materials capable of wi~hstanding the rela-
tîvely high ~emperatures encountered in engine opera~ions. Two
of these sealing elements comprise a pair of rings 42 disposed
in ~espective circumferentially extending grooves 43 ormed in
the outer cylindrical surface of the valve element 27. These
respective pairs of rings 42 are disposed at opposite sides o~ an
aperture 41. An additional sealing ring 44 disposed in circum-
- 30 ferential groove formed in the hub bore 37 may be provided to
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'Z~
1 f~lrther assure comple~e sealing of the valve element~
Completing sealing of each rotary valve element 27
is a pair of axially extending sealing elements 45. These
sealing elements 45 are disposed in respective slots 46 which
are formed in the wall of the valve chamber at opposite ends of
the valve port 21 as can be bes* seen in Figure 1. Figures 5
and 6 illustrate the structure and operation o~ these seals in
substantially g~eater detail with these seals projecting rom
their respective slots 46 into contacting engagement with the
exterior surface of the rotary valve element 27. Each of *hese
axial sealing elements 45 is preferably formed with a side sur-
face 47 which is effectively perpendicular to val~e chamber and
a side surface 48 that is relatively inclined ~o the other sur-
face 47 and ~-hich mate with similarly shaped side walls of ~es-
pective slot 46. A passageway 49 formed in the head section 11
opens to the head chamber 20 and to side wall 47 of the slot
permitting fluid communication therebe~ween. The operational
function of this structural arrangement is that~ during cyclic
opera~ion of the engineg gas pressure developed within a cylinder
during power strokes will produce a force zcting on ~he axial
sealing element 45 tha~ will tend t~ force the sealing element
out of its slot and into positive sealing engagement with the
surface of the valve element. This outwardly directed force re-
sults from the 1uid pressure in the passageway 49 effectivelyacting on the inclined sur~ace of the slot 46.
A sha~t seal 50 is also positioned in a cooperative
recess in the end of each valve chamber extension 15a and 16aO
These seals 50 are located at the end of the chamber opposite
that ~lhere the valve element is positioned and complete the
sealing of each rotary valve element 27 in ~ts respective
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1 chamber lS or 16.
The ro.ary valve apparatus disclosed herein provides
suhstan~ial operaLional advantages over ~he valve apparatus of
S the kno~ prior art and which advantages ma~erially enhances
the eficiency and performance of an inte~nal combustion engine.
The rotary valves are inherently more efficient in con*rolling
gas flow into and ou~ of the engine cylinder *hrough the ability
to locate the ports 21 in rela~ively opposed relationship. This
opposed relationship coupled wi~h the flow path fTom or to the
valve chamber that is relatively obstruction free results in an
~pt7mum gas 10w for scavenging of the gases from the cylinder
at the conclusion of ~he power stToke as well as facilitating
the intake or exhaust of the gases. A further particularly
important advanta~e obtained is the substantially effective
isolation of the valve chambers from each other. This isolation
materially reduces the interference effect resulting rom the
alternating flow patterns which would otherwise detract from
the more,desirable laminar flow patterns obtained wIth this
apparatus. Also, selectivity in adjustment o relative valve
positions as to intake and exhaust permits operation at the most
efficient setting in accordance w;~h power and speed requirements.
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