VALVE ASSEMBLY AND METHOD OF ASSEMBLY
TECHNICAL FIELD
The invention relates to a valve assembly; specifically, a valve assembly
for controlling hydraulic fluid flow in a vehicle, and a method of assembling the same.
BACKGROUND OF THE INVENTION
Valves assemblies for a hydraulic control system, such as in a vehicle
engine, are often complex and require multiple valves to be in alignment with one
another to ensure proper valve seating and control of fluid flow past the valves. For
example, variable bleeed solenoids may requres two poppet valves to seat at valve seats,
with the poppet valves larger than a fluid chamber defined between the valve seats. The
poppet valves must be detached from one another, as neither can fit through the fluid
chamber during assembly. The detachment of the valves may adversely affect their
alignment, making pressure control less precise.
SUMMARY OF THE INVENTION
A valve assembly is provided that has a valve body defining first and
second valve seats and a fluid chamber between the valve seats. The valve assembly
iacludes a first valve that has an extension portion and a plug portion. The plug portion
is configured to be selectively seated at the first valve seat. The extension portion is
configured to extend within the fluid chamber past the second valve seat when the plug
portion is seated at the first valve seat. A second valve is configured to interfit with the
extension portion to connect to the first valve for common movement therewith. The
second valve is configured to be selectively seated at the second valve seat. Fluid flow
through the fluid chamber past the valve seats is controlled by the common movement
of the connected first and second valves. Because the valves are connected, metering
of the fluid past the valves is not diminished by any misalignment of the valves.
Misalignment could more easily occur if the valves moved independently of one
another. Thus, the connected valves offer more precise control of fluid flow.
A method of assembling the valve assembly includes inserting a portion
of the first valve, referred to as an extension portion, through the fluid chamber past the
valve seats. The method further includes inter fitting the second valve with the inserted
portion. The interfitting may be by inserting the extension portion through an opening
formed in the second valve. The method further includes retaining the second valve to
the first valve for common movement with respect to the valve seats. Retaining the
valves to one another may be accomplished by deforming the extension portion to
physically interfere with the second valve.
The above features and advantages and other features and advantages of
the present invention are readily apparent from the following detailed description of the
best modes for carrying out the invention when taken in connection with the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGURE 1 is a schematic cross-sectional view of a valve assembly shown
operatively connected to a vehicle component;
FIGURE 2 is a schematic exploded side view of a first and a second valve
included in the valve assembly of Figure 1;
FIGURE 3 is a schematic cross-sectional fragmentary view of the valve
assembly of Figure 1, showing the first valve seated, allowing full supply pressure to the
vehicle component of Figure 1; and
FIGURE 4 is a schematic cross-sectional fragmentary view of the valve
assembly of Figure 1, showing the second valve seated, allowing zero fluid pressure to
the vehicle component of Figure 1.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings, wherein like reference numbers refer to like
components, Figure 1 shows a valve assembly 10 operatively connected to a component
12, such as a clutch in a vehicle transmission, for controlling fluid pressure to the
component 12. The valve assembly 10 includes an electromagnetic solenoid 14
selectively energized via electrical energy provided to an electrical connector 16 by an
energy source, such as a battery, under the control of a control unit (not shown) to control
the position of rigidly connected valves 18 and 20. The valve 18 is referred to herein as a
first valve and is a poppet-type valve. The valve 20 is referred to herein as a second
valve and is also a poppet-type valve. Specifically, the electrical connector 16 provides
electrical powder through conductive terminals, housed by nonconductive terminal
housing 19 to electrical coils 22 wound around the nonconductive bobbin 21. The
energized electrical coils 22 create a magnetic field that moves an armature 24 axially.
The armature 24 is secured to a pin 26 which translates within a bore of a pole piece 28.
A nomnagnetic end cap 29 contains the armature 24. Translation of the pin 26 is
controlled so that the pin 26 can push against or retract fi:om the first valve 18 to control
the position of the cormected fiist and second valves 18, 20 with respect to an inner
portion of a valve body 30. The inner portion of the valve body 30 defmes a fluid
chamber 32 and first and second valve seats 34, 36, also referred to as metering surfaces.
The fluid chamber 32 establishes fluid conmmunication between the first valve seat 34 and
the second valve seat 36. The inner portion of the valve body 30 also defines a fluid
channel 38 in fluid communication with the fluid chamber 32. Fluid supplied through a
supply port 40 can flow from a supply chamber 33 through the fluid chamber 32 and
through the fluid channel 38, depending on the position of the connected valves 18, 20.
The fluid channel 38 empties fluid from the fluid chamber 32 to an exit chamber 42,
where the fluid is filtered through a filter 44 supported in a retaining ring 46 before
routing via fluid passages 48 to the component 12. The fluid passages 48 are shown only
schematically as a fluid connection between the exit chamber 42 and the component 12.
The passages 48 may be formed by tubes, bored channels, or the like. An outer valve
body portion 50 encloses the exit chamber 42. A plug 52 encloses the supply chamber
33.
The configuration of the first valve 18 and the second valve 20, i.e., their
ability to move commonly in response to pressure fi-om the pin 26 while reliably seating
at the respective valve seats 34, 36 when appropriate is critical to the successful control
of the level of fluid pressure supplied to the component 12. Referring to Figure 2, the
valves 18, 20 are shown in exploded view. The valve 18 includes a plug portion 54 and
an elongated portion, which includes both a rod portion 56 and an exteosicm portion 58
extending from the rod portion 56 to define a shoulder 60.
The second valve 20 has an end 62 through which an opening 64 extends
through to an opposing end 66. The second valve 20 has a tapered surface 67 between
the two ends 62, 65. The extension portion 58 is configured with a length and a diameter
that permit it to be inserted through the opening 64 so that the end 62 rests against the
shoulder 60, and a tip 66 of the extension portion 58 extends beyond the end 65. The
extension portion 58 is made of a deformable material, such as brass, so that the tip 66
may be deformed by a machine tool so that the deformed tip (referred to as 66A in Figure
3) is larger than, and therefore cannot fit through, the opening 64 at the end 65.
Accordingly, the deformed tip 66A physically interferes with removal of the second
valve 20 from the first valve 18. The extension portion 58 is a nonmagnetic material,
although a magnetic material may be used instead. The connected first and second valves
18, 20 are aligned via the extension portion 58 retamed within the opening 64. The
alignment ensures reliable seating of the plug portion 54 at the valve seat 34 and of the
tapered surface 67 at the valve seat 36.
Referring again to Figure 1, the first and second valves 18, 20 are
configured such that both valves 18, 20 may not be seated concurrently, as the axial
distance between the outer surface of the plug portion 54 and the tapered surface 67 of
the valve 20 is greater than the axial distance between the valve seats 34, 36. Thus, as
shown in Figure 1, the connected valves 18, 20 may be controlled by the solenoid valve
14 in combination with the pressure of supply fluid in the supply chamber 33 to be in a
position in which neither valve 18 nor valve 20 is seated, and fluid flows past the valve
seat 36 into the fluid chamber 32 and out past the valve seat 34 to a sump chamber 70
connected to a return sump. Some of the fluid flows through channel 38 out through exit
chamber 42 to the component 12. The pressure of the fluid flowing to component 12 is a
function of the position of the connected valves, 18, 20 relative to the valve seats 34, 36.
As shown in Figure 3, when a surface 71 of the plug portion 54 of valve
18 seats against the valve seat 34, fluid may not exit to the sump chamber 76. Thus, fluid
supplied from the supply chamber 33 to chamber 32 and channel 38, and ultimately
through the exit chamber 42 to the component 12 is at full supply pressure.
As shown in Figure 4, when the solenoid 14 of Figure 1 does not translate
the pin 26 to contact the valve 18, fluid supply pressure from the fluid supply chamber 33
will force the tapered surface 67 of the second valve 20 to seat against the valve seat 36,
allowing all fluid in the chamber 32 to exit through the sump chamber, resulting in zero
fluid pressure in the channel 38 and the exit chamber 42, and ultimately zero pressure to
the vehicle component 12 of Figure 1.
Because the valve 20 does not fit through chamber 32 past either valve
seat 34, 36, the connection of the valves 18, 20 is accomplished only after the first valve
18 is inserted through the fluid chamber 32 (i.e., the rod portion 56 is inserted through the
chamber such that the extension portion 58 extends past the second valve seat 36). The
second valve 20 may be interfit with the extension portion 58 by inserting the extension
portion 58 through the opening 64 in the valve 20, which may be accomplished by
moving the valve 20 to the right in Figure 1 until it reaches the position shown, with the
end 62 of Figure 2 pressing against the shoulder 60. The second valve 20 is then retained
to the first valve 18 for common movement and positioning within the valve body 30 by
deforming the tip 66 of the extension portion 58 to physically interfere with the second
valve 20, as shown in Figure 3 in which the deformed tip is indicated as 66A and extends
beyond the end 65. The connected valves 18 and 20 are appropriately aligned due to the
insertion of the extension portion 58 through the opening 64, which prevents relative
radial movement of the valves 18, 20.
While the best modes for carrying out the invention have been described
in detail, those familiar with the art to which this invention relates will recognize various
alternative designs and embodiments for practicing the invention within the scope of the
appended claims.
WE CLAIM:
1. A valve assembly comprising:
a valve body defining first and second valve seats and a fluid chamber
therebetween;
a first valve having an extension portion and a plug portion; wherein the
plug portion is configured to be selectively seated at the first valve seat; wherein the
extension portion is configured to extend within the fluid chamber past the second valve
seat when the plug portion is seated at the first valve seat;
a second valve configured to interfit with the extension portion to connect
to the first valve for common movement therewith; and wherein the second valve is
configured to be selectively seated at the second valve seat, fluid flow through the fluid
chamber past the valve seats thereby being controlled by common movement of the
connected first and second valves.
2. The valve assembly of claim 1, wherein the second valve defines
an opening therethrough, and wherein the extension portion fits through the opening and
is configured to be deformable to retain the second valve to the first valve.
3. The valve assembly of claim 2, wherein the extension portion is a
nonmagnetic material.
4. The valve assembly of claim 2, wherein the first valve has a
shoulder at an end of the extension portion, and wherein the second valve rests against
the shoulder when the second valve is retained to the first valve.
5. The valve assembly of claim 4, wherein the first valve has a rod
portion extending from the plug portion and sized to fit within the fluid chamber without
contacting with either of the valve seats; and wherein the rod portion defines the
shoulder.
6. The valve assembly of claim 1, wherein the valve body defines a
fluid channel in fluid communication with the fluid chamber between the valve seats;
wherein the connected first and second valves are configured so that the valves may not
be concurrently seated.
7. The valve assembly of claim 6, further comprising:
a solenoid operatively connected to the first valve and selectively
energizable to control movement to the connected valves.
8. A method of assembling a valve assembly, wherein the valve
assembly has a valve body with first and second valve seats and a fluid chamber
therebetween; wherein the valve assembly includes a first valve configured to seat at the
first valve seat and a second valve configured to seat at the second valve seat,
comprising:
inserting a portion of the first valve through the fluid chamber past the
valve seats;
interfitting the second valve with the portion of the first valve; and
retaining the second valve to the first valve for common movement with
respect to the valve seats.
9. The method of claim 8, wherein the retaining includes deforming
the portion of the first valve to physically interfere with the second valve.
10. The method of claim 8, wherein the interfitting includes inserting
the portion of the first valve through an opening formed through the second valve.
11. A valve assembly for controlling fluid pressure to a vehicle
component, comprising:
a valve body defining first and second valve seats and a fluid chamber
therebetween; and wherein the valve body further defines a fluid charmel in fluid
communication with the fluid chamber and with the vehicle component;
first and second valves connected for common movement; wherein the
first valve has a plug portion configured to seat at the first valve seat and an elongated
portion extending through the fluid chamber past the second valve seat; wherein the
second valve is configured to seat at the second valve seat; wherein the second valve is
connectable to the elongated portion of the first valve when the elongated portion extends
past the second valve seat; wherein the first and second valves are configured so that the
connected valves may not be concurrently seated; and
a solenoid operatively coimected to the valves and controllable to
selectively move the connected valves and thereby control metering of fluid past the first
and second valve seats to control fluid pressure m the fluid channel.
12. The valve assembly of claim 11, wherein the first valve defines a
shoulder; wherein the second valve defines an opening therethrough; and wherein the
extension is configured to extend through the opening with the second valve pressed
against the shoulder when the first and second valves are connected.
13. The valve assembly of claim 12, wherein the elongated portion is
configured with a deformable tip that extends outward of the opening and in contact with
the second valve when deformed to thereby retain the second valve to the first valve.

A valve assembly is provided that has a valve body (30)
defining first and second valve seats (34, 36) and a
fluid chamber (32) between the valve seats. The valve
assembly includes a first valve (18) that has an
extension portion (58) and a plug portion (54) . The
plug portion (54) is configured to be selectively
seated at the first valve seat (34). The extension
portion (58) is configured to extend within the fluid
chamber (32) past the second valve seat (36) when the
plug portion (54) is seated at the first valve seat
(34). A second valve (20) is configured to interfit
with the extension portion (58) to connect to the first
valve (18) for common movement therewith. The second
valve (20) is configured to be selectively seated at
the second valve seat (31) . Fluid flow through the
fluid chamber (32) past the valve seats (34, 36) is
controlled by the common movement of the connected
first and second valves (18, 20).