Note: Descriptions are shown in the official language in which they were submitted.
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S P E C I F I C A T I O N
BACKGROUND OF THE INVENTI0N
1. Field of the Invention
In one aspect, this invention relates to vacuum control ¦
valves. In a further aspect, this invention relates to servo- ¦
controlled vacuum programmers.
2. Prior Art
Linear vacuum programmers or diverters are known in
the art. One example is shown in U.S. Patent 3,983,930 issued
to Rudolph J. Franz. This patent shows a linear diverter valve
with an elongated body and a bore extending longitudinally
therein. A plurality of ports are axially spaced along the body
and are in fluid communication with the bore. A diverter valve
assembly is mounted within the bore; the diverter valve has
sealing means at each end which seal the bore. The diverter
valve also has a reduced center section which allows fluid flow
within the bore between the two sealing means. Therefore, any
ports which lie between the sealing means will be in fluid
communication with each other. As the two sealing means are
moved longitudinally along the bore, selected ports can be
interconnected by means of the reduced portion of the valve.
A problem arises with the prior art devices in assembl-
ing the valve in a system. Where a plurality of devices are to
be controlled by the programmer, a number of port-connecting
nipples are pl-ac-ed~on th~ l~a~~ay. Th-e ports and nipples are
placed in proximity and, therefore, the ports are spaced about
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the same distance apart as the nipples. This has created a
problem in that the size of the programmer has been determined
by the port spacing which in turn has been dictated by the
size of the port-connecting nipples.
According to the present invention, there is
provided a linear vacuum programmer having body means including
a first body member provided with a longitudinal bore therein
and at least one control aperture communicating with the bore.
The body means has a second body member attached to the first
body member and forming therebetween at least one manifold
chamber, the control aperture providing fluid communication
between the bore and the manifold chamber. The body means
includes means defining a fluid pressure inlet port communicating
with the bore and adapted for connection to a source of fluid
pressure. Valve means is slidably disposed in the bore therein
and operable upon movement therein to cover and uncover the
control aperture thereby controlling fluid communication between
the bore and manifold chamber.
In a specific embodiment of this invention, the
first body portion may have two or more, i.e., a plurality,
of ports or apertures longitudinally disposed along the first
body portion. In such an arrangement, each of the apertures
provides operating fluid pressure to a separate device and
would generally have its own separate through manifold chamber.
The manifold chambers
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; thus permit the port apertures to be closely spaced for conven-
ience of valving, yet permit the port connection nipples to be
spaced apart to permit ease of installation.
As yet a further feature, the movable plunger of this
invention is provided with a single circumferential sealing
lip disposed about a core. The seal is in sliding contact with
the bore and provides an effective seal against the inner
. periphery of the bore.
BRIEF DESCRIPTION OF THE DRAWI~GS
In the accompanying drawing:
Figure 1 is a diagrammatic view of a linear programmer
of this invention installed in an automotive air conditioning
system;
Figure 2 is a section view of the linear programmer
of Figure l; and
Figure 3 is a section view ta~en along section-indica-
ting lines 3-3 of Figure 2.
DESCRIPTIO~ OF THE PREFERRED EMBODIMENT
The linear programmer 10 shown in Figure 2 will be
described with reference to its function in an automotive heating ¦
and air conditioning system such as that shown in Figure 1.
The linear programmer comprises a first body portion 12 which
has a longitudinal bore 14 therein. The first body portion 12
has a pair of upstanding solid studs 16 which can be used to
attach the programmer to the vehicle mounting structure. A
plurality of port apertures ~8, 20 and 22 are provided in the
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; first body portion for communicating with the bore 14.
¦ A second body portion 24 defines a manifold communicating
with apertures 18, 20 and 22. The body portion 24 is preferably
~ a separate member and is sealed to the first body member 12 along
~ a seam 26 to create a pressure tight seal. The manifold is
divided into separate chambers preferably by two projections 28
provided on the first body member thereby creating three manifold
chambers 30, 32 and 34 between the hody portions. Three nipples
36, 38 and 40 are provided for the manifold chambers and extend
radially outward from the second body portion, thereby providing
means to attach the programmer to external parts of the system.
The nipples define, respectively, ports 37, 39 and 41, each
communicating with a separate chamber or portion of the manifold.
In the embodiment of the invention illustrated in Figure 2,
the nipples are spaced such that port 37 connects to chamber 30,
port 39 connects to chamber 32, and port 41 connects to chamber
34. In the presently preferred practice, the body portions 12
¦ and 24, as mentioned above, are formed of separate members and
preferably of plastic material. With reference to Figure 3,
the second body portion 24 mates with the first body portion 12
at a parting line, denoted 26, to typically form manifold
chambers 30, 32 and 34, with only manifold chamber 30 being shown
in Figure 3 for clarity and simplicity. The first and second
body portions 12 and 24 are joined along parting line 26 in a
fluid pressure tight seal in any suitahle manner, as for example
b adhesives. Hcwever, the technique of we~dment by fusicn using
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,' ultrasonic waves has been found particularly suitable and is
¦~ the preferred method of joining the two body portions. It will
be understood, however, that the first and second body portions
~ could be formed by other arrangements, as for example, by
¦ molding the programmer in halves about a vertical line of symmetry
¦ in Figure 3 and thereafter joining the halves, or by molding
the portions integrally as a one-piece unit.
A cap 42, preferably formed of foam material, is attached
¦ to one end of the first body member 12 to partially close bore
¦ 14. An aperture 43 provided in cap 42 allows a wire 44 to pass
into the bore. A plunger 46 is slidably disposed in the bore 14,
and has one end of wire 44 connected thereto for effecting move-
ment of the plunger. The plunger 46 has a core 48 and a radially
¦ resilient circumferential seal 50 provided therearound. Move-
¦ ment of the wire thus causes movement of t~e plunger and seal 50
which connects and disconnects apertures 20 and 22 successively
fluidly to the bore 14. The wire 44 can be moved by various
means, a solenoid being a preferred means.
l In operation, as shown, fluid pressure and typically a vacuum
20 ¦ is supplied to nipple 36, manifold 30 and to bore 14 via aperture
18. As a result, bore 14 from its end wall nearest aperture or
inlet 18 to the plunger 46 is constantly maintained at a reduced
pressure. The apertures 20 and 22 are preferably located at a
location in the first body portion 12 most remote from the inlet
25 ¦ aperture 18, and are closely spaced for quick valving with
_ minimal movement of plunger 46. Manifolds 32 and 34 are thus
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' shaped so as to permit greater spacing between nipples 3~ and ~0
¦I for ports 39, 41 than the spacing between ports 20 and 22. For
example, in the presently preferred embodiment ,he apertures 20
and 22 are spaced about l/32 of an inch apart while the nipples
are spaced 3/lO of an inch apart. This configuration allows
easy switching or valving of ports 20, 22 and yet permits easy
assembly. As a further refinement, the ports 20, 22 can be
disposed in the lower wall of body member 12 at an angle. If
the ports are disposed at a converging angle, the portions of the
ports at the base 14 can be closer together than the portions of
the ports at the manifolds 32, 34. This allows an even greater
spacing differential between the valving ports 20, 22 and the
nipples.
To provide a further understanding of the linear programmer's
operation, Figure l shows a typical automotive air conditioning
system with the programmer lQ shown installed in the system.
In general, such systems have a housing (not shown) contain-
ing a plenum which is mounted in the vehicle. The plenum is
defined by a plurality of ducts which can be opened or closed
in predetermined sequences to feed heated, cooled, blended or
fresh air into the passenger compartment. A blower is normally
associated with the plenum to move the air into the passenger
compartment. The exact plenum and blower arrangement is dictated
by design considerations of the vehicle to which the plenum is
25 ! a ached.
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In the system shown in Figure 1, a multifunctional blend
~¦ servomotor 60 is in vacuum connection with a temperature sensor
~! 62 so that changes in temperature will cause sensor 62 to vary a
vacuum signal to servomotor 62 to activate the blend motor. The
servomotor 60 has output actuator thereof operatively connected
to the wire 44 of linear programmer 10 for moving ~he plunger 46
to cover and uncover apertures 20 and 22.
In the system of Figure 1, the linear programmer 10 ports
vacuum to a vacuum operated water valve servomotor 66 which
controls a flow of heater water through a heater core in response
to vacuum signal from port 40.
Nipple 38 is connected by a vacuum line to a selector or
distributor 68 which is used to set the desired cycle of heating
and air conditioning. The selector 68 in combination with the
linear programmer 10 controls flow directing doors which direct
air flow within the plenum.
In general, the doors 70, 72 function in a manner well
known in the art. The recirculating fresh air door 70 controls
the circulation of air into the plenum from outside the vehicle
or from the passenger compartment. A temperature blend door,
not shown, controls a flow of blended air within the plenum and
a by pass door, not shown, controls the flow of cooled air through
the plenum. The blend door and by pass door are controlled ~y
the blend servomotor 60.
A panel/defrost door 72 governs the fl~w of heated or cooled
air to the defrosters or air conditioning panels and a floor door
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74 controls the flow of conditioned air to upper or lower parts
l of the vehicle passenger compartment.
The workings of the automotive air conditioning system are
well known to those skilled in the art, and a detailed explanation
is omitted in the interest of brevity. Further detailed
description of such systems can be found in U.S. Patent 3,983,930
issued to Franz, especially columns 3-10, and U.S. Patent
3,856,045 issued to Kenny, Et Al, especially columns 3-8.
Various modifications and alterations to this invention will
become obvious to those skilled in the art without departing
from the scope and spirit of this invention. It is understood
that this invention is not limited to the illustrative embodiments
set forth hereinbefore, but is limited only by the following
claLms:
