Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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This invention relates to an improved regula~or
valve particularly for use in a transmission mechanism.
It h~s been found that in connection with modern
engines for vehicles complex lin~ages and complex carburetion
dev~ces are employed inducing forces resisting movement of
-the throttle pedal of significant value, making it important
that additional forces not be introduced in the linkage system.
In addition, it has been found that with modern vehicles the
commonly used manifold vacuum pressure signal is no longer
as reliable due to the type of controls placed on the engine
today such that direct mechanical linkages are now desirable
for operating the throttle valve within a hydraulic control
system for a transmission~ With known direct operating
throttle valves, a significant amount of force is required
as the valve responds to movement of the throttle pedal and
in particular at the heavy throttle or nearly full depressed
throttle positions a rather large amount of force is required
to move the throttle pedal.
The present invention overcomes the above difficulties
in a throttle valve mechanism in that a pilot operating throttle
valve is utilized wherein the forces added to the throttle
linkage to enable the throttle valve to respond to movement
thereof may be substantially zero since only a pilot valve
member is connected to be moved by the throttle pedal. A
movable valve member is provided within the throttle valve
~hich has a control valve member`movable therein and the
movable valve member follows movement thereof. A differential
area is provided on the movable valve member responsive to
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fluid pressure and a spring is provided opposing force
developed by the differential area. The spring and
differential area forces are imposed only on the movable
valve member and are not imposed on the linkage mechanism
connected to the throttle pedal. In addition, the
invention carries out the construction in a very simple
manner providing a hollow movable valve member having
slidable therewithin a pilot valve control member connected
to the throttle mechanism. The valve member is mounted
in a bore having a pressure inlet, pressure outlet and
regulating ports. The inlet port is connected to a source
of fluid pressure, and the valve member has a plurality
of ports communicating with the ports in the bore. The
control member has means therein adapted to establish a
connection between the inlet port and the outlet port through
the ports in the valve member. The outlet port being
, connected to the regulating port so that movement of the
control member will be followed by the valve member to
produce a pressure in the outlet port which varies with
the position of a control member and therefore,,the position
of the throttle mechanism.
The single FIGURE of the drawings is a schematic
illustration of a valve embodying the principles of the
present invention.
Referring to the drawing, the regulating valve 10
of the present invention is adapted to cooperate in a trans-
mission control system with a source of fluid pressure 12,
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a primary regulator valve 14 and a hydraulic control system
16, In general, the ~unction of the valve 10 is to provide .
a signal to the transmission hyaraulic control system 16
which varies with movement of a control member of the engine,
such as the throttle. By way of example, the invention is
illustrated as a throttle valve for the control system. As
manufactured and used the valve 10 would be within and a
part of the hydraulic control system 16.
The source 12 supplies--pressure to primary regulator
valve 14 which regulates such pressure and supplies such
regulated pressure to a conduit 20, which is connected to the
hydraulic control system 16 and to valve 10. The valve 10
develops a regulated pressure which varies directly ~ith the
position of the throttle and supplies same to a conduit 22,
which connects to the regulator valve 1~ to influence the
primary regulator valve in accordance with known practice in
the transmission hydraulic control system art, to control
other unctions within the transmission such as the points at
Which ratio changes take place in the transmission. The.
valve 10 is generally comprised of a bore 26 formed within a
section 28 of a valve body for the hydraulic control system.
The bore 26 has slidable therewithin a movable
valve member 30, The valve member 30 has a bore 32 therein
which is adapted to receive a movable control member 34.
A very light spring 35 engages member 34 and urges same to
the left as viewed in the drawing. Within the bore 26, a
spring 36 is provided urging valve member 30 to the left,
as v;`.ewed in the drawing, against a stop 38 connected to the
valve section 28. Spring 36 is confined in bore 26 by a
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stop 39. A throttle cam 40 is provided, which is connected
by linkage member 42 to be moved by a throttle pedal 44
for the vehicle. The li~kage illustrated is schematic only
and is only a sample of types of linkages which may be used.
In general, as the throttle 44 is depressed, linkage 42 will
move to the right and rotate cam 40 about the pivot 46.
The cam has a control surface'4~ thereon to engage the
movable member 3~ and move same to the right as the throttle
is depressed.
The valve member 30 has ports 50,52 and 54 therein.
~he movable control member 34 has an elongated groove 56
therein. The valve member 30 includes lands 60, 62, 64 and
66. A large land 68 is also provided on the right hand end
thereof which slides within an enlarged diameter section
70 of the bore 28. The bore 28 includes ports 72, 74, 76
~nd 78.
Port 72 is an exhaust port which will be connected
to the sump for the transmission control system. Port 74
is an output port which is adapted to contain the product
of the valve 10 and is connected to the output conduit 22.
Port 76 is the pressure inlet port connected to the conduit 20
having regulated fluid pressure therein. Port 78 is a
regulating port, this port being connected -to the pressure
within the conduit 22. Pressure in port 78 is communicated
to the differential area between lands 66 and 68 and creates
orce on movable member 30 tending to move same to the right,
compressing the spring 36.
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~ s is known in the art, the operation of a
regulating valve system is such that pressure in the output
port 74 is communicated to a differential land area which
develops a force in opposition to the force of a spring,
such as spring 36, and thus a regulated pressure is provided
in the conduit 22. In the present invention it will be
seen that as the control member 34 moves to the right, assumlng
the valve is at rest as illustrated in FIGURE 1, a communication
will be opened up by the groove 56 communicating.the port 54
of valve member 30 with port 52, As this happens, pressure
in port 52 will be communicated through port 74 and port 78
to act on khe differential land area between lands 66 and 68,
and the valve member 30 will move to the.right a sufficient
extent to interrupt the connection made by groove 56 and
the relative positions of valve member 30 and member 34 are
as illustrated in FIGURE 1 once again. However, each of the
members 30 and 3~ have been moved to the right as the throttle
is depressed, As members 30 and 34 assume an equilibrium
position to the right of that illustra-ted in FIGURE i, the
spring 36 becomes more compressed and creates additional
force on valve member 30 and thus an increased regulated
pressure is provided in conduit 22.
As will be apparent from the above description,
as the throttle 44 is depressed rotating cam 40, and control
member 34 is moved to the right against the force o the very
light spring 35, it will be seen that due to the pilot
operation, there are no forces on control member 34 e~cept
for the very small force of the spring 35. Thus, a
regulating valve has been provided which can be adapted to
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respond to the throttle position as described above
and wherein substantially no additional force is;required
to be transmitted through the linkage between the throttle
and the carburetor to operate the regulating valve 10.
As described above, this is important in that in more modern
vehicles where it is desirable that a mechanical connection
between the throttle and throttle valve be provided, due
to the increasing complexity of carburetors and throttle
linkages being used with engines, the forces resisting
movement of pedal 44 are significant to an extent to make
operation of pedal 44 uncomfortable to the operator of the
vehicle. As described above, the present invention over-
comes this problem by providing a pilot operation so that
the movement o~ control member 3~ requires extremely small
force.
. Although the valve 10 is described as used in
conjunction with a throttle for a vehicle engine to produce
a regulated throttle pressure varying with throttlè position
for a hydraulic control system 16, it should be apparent
that the unique regulating valve 10 can be used in connection
with many other control functions wherein a pressure is
desired which varies directly with the position of a movable
member such as cam member ~0. Thus, the utility of the
described improved pilot operated regulator valve 10 is very
widespread in that it is adaptable to convert a manual move-
ment to a pressure varying directly therewith without the
necessity of adding a significant amount of resistant force
to the mechanism~
