Note: Descriptions are shown in the official language in which they were submitted.
CA 02843785 2014-02-27
TITLE OF THE INVENTION
AIR SUSPENSION PRESSURE DISPLAY
FIELD OF THE INVENTION
The invention relates to the field of air suspension systems for trucks and
trailers,
and in particular, to displays for informing operators about the pressure
level in air
suspension systems.
BACKGROUND OF THE INVENTION
Air suspension systems are used in vehicles to provide a smooth and constant
ride.
They may be found in all types of vehicles, including in particular, trucks
and trailers.
An air pump or air compressor pressurizes the air within one or more air bags
(or air
springs), raising the chassis of the vehicle from the axles. Typically, the
air springs are
inflated with pressurized air until a certain ride height is reached (the ride
height being
the distance between the bottom of the trailer and the center of the axle).
For heavier
loads, a higher air pressure within the air springs is needed before the ride
height is
reached. The air within the air springs provides the vehicle with suspension
by isolating
the vehicle's contents from bumps and vibrations caused by travel on the road.
Currently, load operators are able to determine the particular air pressure
within
the system by reading a pressure gauge. These gauges are typically located in
the cabs of
the trucks, or the gauges are on sides of the trailers. Therefore, a person
loading a trailer
would not be able to monitor the air pressure without either periodically
going inside the
cab or to the side of the trailer or communicating in some manner with a
person reading
the gauges. This is both time-consuming and prone to error (e.g. if there is
an error in
1
CA 02843785 2014-02-27
communications between the load operator and the person within the cab). In
addition,
the gauges may be difficult to read, especially at night. All of the above
create a safety
issue.
Accordingly, a need exists for an improved system for monitoring the air
pressure
within an air suspension system that overcomes the deficiencies noted above.
SUMMARY OF THE INVENTION
According to the invention, a series of lights provides a simple and easy-to-
read
display of the relative air pressure within the air springs. In one
embodiment, various
lights will light up when the air pressure is below, at, or above the
appropriate air
pressure. The color and number of lights can be varied. The lights may be
located
conveniently at the side of the trailer so that the load operator can easily
see them.
Adjustment mechanisms are provided that allow the operator to configure or
calibrate the
air pressure at which the lights will be illuminated.
A system for displaying relative air pressure within one or more air springs
of an
air suspension system for vehicle comprises an intake line, a manifold, one or
more
pressure switches, one or more lights, and a power source. The intake line is
operatively
connected to the one or more air springs. The manifold is connected to the
intake line.
The one or more pressure switches is connected to the manifold, and each of
the pressure
switches is configured to close when a particular air pressure is reached
within the
manifold. Each of the pressure switches is operatively connected to one of the
one or
more lights and the one or more lights are visible along a side of the
vehicle. The power
source is connected to the pressure switches. When one of the pressure
switches is
closed, a corresponding one of the one or more lights is illuminated.
2
CA 02843785 2014-02-27
In another embodiment, the intake line is connected to the one or more air
springs
through a second line that is connected to the one or more air springs.
In a further embodiment, the intake line is connected to the second line
through a
T-j oint.
In yet another embodiment, the number of pressure switches is three.
In still another embodiment, the power source is a battery.
In another embodiment, the power source is located on the vehicle.
In a further embodiment, the system further comprises a box, where the box
houses the manifold, the pressure switches, and the lights.
In yet another embodiment, the system further comprises a second box and one
or
more secondary lights located on the second box. The second box is located on
an
opposite side of the vehicle from the lights. Each of the pressure switches is
operatively
connected to one of the one or more secondary lights. When one of the pressure
switches
is closed, a corresponding one of the one or more secondary lights is
illuminated.
In another embodiment, each of the pressure switches comprises an adjustment
mechanism to allow for the adjustment of the particular air pressure when each
of the
pressure switches closes.
In yet another embodiment, the adjustment mechanism comprises a screw for
adjusting the particular air pressure.
3
CA 02843785 2014-02-27
In a further embodiment, the one or more lights are of different colors when
illuminated. The first one of the one or more lights may be green. The second
one of the
one or more lights may be red. The third one of the one or more lights may be
amber.
In yet another embodiment, where there are three lights, a first one of the
three
lights is illuminated when the particular air pressure is at a first level
that is lower than a
correct air pressure for said air suspension system. A second one of the three
lights is
illuminated when the particular air pressure is at a second level that is
approximate to the
correct air pressure for the air suspension system. A third one of the three
lights is
illuminated when the particular air pressure is at a third level that is above
to the correct
air pressure for the air suspension system.
In another embodiment, a system for displaying relative air pressure within
one or
more air springs of an air suspensions system for a vehicle comprises an
intake line, an
adjustment box, and a display box. The intake line is operatively connected to
the one or
more air springs. The adjustment box comprises a manifold connected to the
intake line
and one or more pressure switches operatively connected to the manifold, each
of the
pressure switches configured to close when a particular air pressure is
reached within the
manifold. The display box comprises one or more lights, where each of the
pressure
switches is operatively connected to one of the one or more lights and where
the one or
more lights are visible along a side of the vehicle. When one of the pressure
switches is
closed, a corresponding one of the one or more lights is illuminated.
In yet another embodiment, the system further comprises a power source
connected to the pressure switches. The power source may be a battery or it
may be
located elsewhere on the vehicle.
4
CA 02843785 2014-02-27
In a further embodiment, the intake line is connected to the one or more air
springs
through a second line that is connected to the one or more air springs. The
intake line
may be connected to the second line through a T-joint.
In another embodiment, a system for displaying relative air pressure within
one or
more air springs of an air suspensions system for a vehicle comprises an
intake line, a
manifold, one or more pressure switches, a light, and a power source. The
intake line is
operatively connected to the one or more air springs. The manifold is
connected to the
intake line. The one or more pressure switches is operatively connected to the
manifold,
and each of the pressure switches configured to close when a particular air
pressure is
reached within the manifold. Each of the pressure switches is operatively
connected to
the light, where the light is capable of illuminating at two or more different
colors. The
power source is connected to the pressure switches. When one of the pressure
switches is
closed, the light is illuminated at one of the two or more different colors.
The foregoing was intended as a summary only and of only some of the aspects
of
the invention. It was not intended to define the limits or requirements of the
invention.
Other aspects of the invention will be appreciated by reference to the
detailed description
of the preferred embodiments. Moreover, this summary should be read as though
the
claims were incorporated herein for completeness.
BRIEF DESCRIPTION OF THE DRAWINGS
The preferred embodiment of the invention will be described by reference to
the
drawings thereof, in which:
Fig. 1 shows a schematic view of one embodiment of the invention incorporated
with an air suspension system;
5
CA 02843785 2014-02-27
Fig. 2 shows a view of the invention attached to the chassis of a vehicle;
Fig. 3 shows a view of the invention; and
Fig. 4 shows a schematic view of another embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to Figs. 1 and 2, an air suspension system 10 for a vehicle
comprises a
plurality of air springs 12. The vehicle may be a trailer, a truck, or another
similar
device. The air springs 12 support the chassis 4 of the vehicle on the axles
16 and are
connected together through air intake lines 14 that feed air into the air
springs 12. As air
is fed into the air springs 12, the air springs 12 inflate, raising the
chassis 4 from the axles
16 (and thereby increasing the ride height). A levelling valve 18 controls the
flow of air
into the air intake lines 14 from an air compressor 20. For example, the
levelling valve
18 allows for air to be fed into the air intake lines 14 until a certain ride
height is reached,
at which time, the levelling valve 18 prevents further air from being fed into
the air intake
lines 14. Along one of the air intake lines 14, a T-joint 22 is provided. A
secondary air
line 24 extends from one arm of the T-joint 22 to a detection unit 26.
As shown in Fig. 2, the detection unit 26 comprises a panel 28. The detection
unit
26 is preferably located on the side of the chassis 4 at a location that would
allow the
panel 28 to be easily visible. Preferably, the detection unit 26 is a box. The
box may be
enclosed or it may be partially open. One or more lights 30, 32, 34 is
provided on the
panel 28. In the embodiment shown in Figs. 1 and 2, the panel 28 comprises
three lights
30, 32, 34 arranged vertically; however, a different number of lights (such as
two, four,
five, etc.) in a variety of orientations is also possible. Any suitable light
may be used,
such as those manufactured by Truck-Lite Global LLC. The detection unit 26
also
comprises one or more pressure switches (or senders) 40, 42, 44. In the
embodiment
6
CA 02843785 2014-02-27
shown in Figs 1 and 2, the pressure switches 40, 42, 44 are located on the
panel 28;
however, they may also be placed on other locations on the detection unit 26.
Preferably,
the number of pressure switches 40, 42, 44 corresponds to the number of lights
30, 32,
34. Referring to Fig. 1, it is also possible to have a secondary detection
unit 27. This
secondary detection unit 27 may be placed on another location on the chassis 4
(e.g. on
the other side of the chassis 4). The secondary detection unit 27 may comprise
a
secondary panel 29 with one or more secondary lights 50, 52, 54. Preferably,
the number
of secondary lights 50, 52, 54 corresponds to the number of lights 30, 32, 34.
Referring to Fig. 3, the secondary air line 24 extends from the T-joint 22
into the
detection unit 26 and is attached to an intake 62 of a manifold 60. In the
embodiment
shown in Fig. 3, the manifold 60 has three outputs 64. Each of the outputs 64
is
connected (either directly or through some other connection) to one of the
pressure
switches 40, 42, 44. In embodiments where the number of pressure switches 40,
42, 44 is
increased or decreased, the number of outputs 64 on the manifold 60 is
adjusted
accordingly. The pressure switches 40, 42, 44 may be of the type that are
commercially
available, such as those manufactured by Honeywell International Inc.
Each of the pressure switches 40, 42, 44 comprises adjustment mechanisms 70,
72,
74. The pressure switches 40, 42, 44 are switches that close an electrical
contact when a
certain pressure is reached. The adjustment mechanisms 70, 72, 74 allow for
the
adjustment of the pressure level at which the switches are closed. The
detection unit 26
further may comprise a power source 66, such as a battery. In another
embodiment, the
detection unit 26 may take electrical power from a source on the vehicle
through wire 68
(e.g. from the electrical power used to power the clearance lights on the
vehicle), as
shown in Fig. 2. Each of the pressure switches 40, 42, 44 is connected to
either the
power source 66 or wire 68 and to one of the lights 30, 32, 34.
7
CA 02843785 2014-02-27
As the manifold 60 is connected to the secondary air line 24 (which is
connected
to the T-joint 22 and the air intake lines 14) the air pressure within the
manifold 60 is the
same as the air pressure within the air intake lines 14 and the air springs
12. Each of the
pressure switches 40, 42, 44 can be preconfigured to close at different
pressures.
Therefore, when the pressure within the air springs 12 reaches one of those
preconfigured
pressures, the appropriate pressure switch 40, 42, 44 is closed, resulting in
the
corresponding light 30, 32, 34 being illuminated.
In this manner, the lights 30, 32, 34 can provide a relative display of the
air
pressure within the air springs 12. For example, the detection unit 26 may
cause the first
light 30 to be illuminated when the air pressure within the air springs 12
reaches a
particular level (e.g. 55 psi). This may be used to indicate when the air
springs 12 are
nearing their appropriate limit (i.e. the vehicle is nearing its correct
load). The second
light 32 may be illuminated when the air pressure in the air springs 12
reaches a higher
level (e.g. 60 psi). This may be used to indicate when the air springs 12 are
at their
appropriate limit (i.e. the vehicle is at its correct load).
The third light 34 may be illuminated when the air pressure within the air
springs
12 reaches a third, still higher, level (e.g. 65 psi). This may be used to
indicate when the
air springs 12 are over their appropriate limit (i.e. the vehicle is over its
correct load).
This may be used as an indication to the operator that the vehicle is
overloaded and that
some of its contents needs to be removed.
The exemplary air pressure levels given above for triggering the illumination
of
the lights 30, 32, 34 are only meant to be one example of the air pressure
levels that may
be used. The particular air pressure levels to be used can be adjusted to suit
the particular
circumstances, which may take into account the particular air springs 12, the
size of the
vehicle, and the operating and safety regulations of a particular
jurisdiction. The
adjustment of the pressure levels needed to trigger the illumination of the
specific lights
8
CA 02843785 2014-02-27
30, 32, 34 can be made using the adjustment mechanisms 70, 72, 74. The
adjustment
mechanisms 70, 72, 74 allow the operator to adjust the air pressure levels at
which the
corresponding lights 30, 32, 34 will illuminate. Preferably, the adjustment
mechanisms
30, 32, 34 comprise a screw that may be turned (e.g. using a screwdriver or an
Allen
wrench) to effect the adjustment. In other embodiments, the adjustment
mechanisms 30,
32, 34 may also be electronically manipulated.
In another embodiment, the lights 30, 32, 34 may be of different colors when
illuminated. For example, the first light 30 may be green when illuminated,
the second
light 32 may be amber or yellow when illuminated, and the third light 34 may
be red
when illuminated. These colors correspond to colors that the operator may
easily
recognize as meaning "safe", "caution", and "danger", respectively. For
example, when
the first light 30 is illuminated (with the color green), this may indicate to
the operator
that he or she may continue to load the vehicle. When the second light 32 is
illuminated
(with the color amber), this may indicate to the operator that he or she
should consider
stopping any further loading of the vehicle. When the third light 34 is
illuminated (with
the color red), this may indicate to the operator that he or she should reduce
the load of
the vehicle. Although the colors green, amber (or yellow), and red have been
described,
it is to be understood that any combination of colors may also be used.
Referring to Fig. 1, in situations where the secondary unit 27 is present, the
secondary lights 50, 52, 54 on the secondary panel 29 should preferably
correspond in
function to the lights 30, 32, 34. For example, if the secondary unit 27 is
located on the
other side of the chassis 4 from the detection unit 26, then the operator can
view either
the panel 28 or the secondary panel 29 easily from either side of the vehicle.
The
detection unit 26 and the secondary unit 27 should be connected together via
connection
78 to allow the secondary lights 50, 52, 54 to function in the same manner as
the lights
30, 32, 34. The connection 78 may be wired or wireless (e.g. by Bluetooth
communications).
9
CA 02843785 2014-02-27
As mentioned above, although the embodiment shown in Fig. 1 shows the panel
28 having three lights 30, 32, 34, it is to be understood that the number of
lights may be
varied. For example, it is possible to only use two lights. In such an
embodiment, the
first light may be illuminated when the air pressure reaches a level that is
at its
appropriate limit, and the second light may be illuminated when the air
pressure reaches a
level that is above its appropriate limit. Similarly, it is also possible to
use more than
three lights. In such an embodiment, the additional light may be illuminated
when the air
pressure is, for example, more than 10 psi lower than the appropriate limit.
Preferably,
the number of lights should correspond to the number of pressure switches
(such that
each light is connected to one pressure switch).
In another embodiment, instead of the panel 28 providing three separate lights
30,
32, 34 that display different colors when illuminated, the panel 28 may
comprise a single
light that is able to display different colors (depending on the air pressure
level). For
example, the light may illuminate green when a first air pressure level is
reached, amber
when a second air pressure level is reached, and red when a third air pressure
level is
reached. These air pressure levels may correspond to the same air pressure
levels used
when separate lights 30, 32, and 34 are used. In this embodiment, the number
of pressure
switches needed would correspond to the number of discrete air pressure levels
used.
Fig. 4 shows a further embodiment. In this embodiment, the secondary air line
24
extends from the T-joint 22 to an adjustment unit 80. The manifold 60 and the
pressure
switches 40, 42, 44 are located within the adjustment unit 80. A separate
display unit 90
is connected to the adjustment unit 80 but located apart from it. The lights
30, 32, 34 are
located on the display unit 90. The adjustment unit 80 and the display unit 90
are
connected together through a local connection 95. The local connection 95 may
be wired
or wireless.
CA 02843785 2014-02-27
In another embodiment, the secondary air line 24 is directly connected to one
of
the air springs 12, instead of connecting to one of the air intake lines 14
through the T-
joint 22.
The invention provides a convenient and easy-to-understand indication of the
relative air pressure within the air springs 12. It allows the operator to
quickly determine
whether the load of the vehicle is within correct (and safe) limits. Also, by
providing the
detection unit 26 on the side of the chassis 4, the operator is able to see
firsthand the
relative air pressure within the air springs 12, without having to enter the
cab of the
vehicle or communicate with someone else within the cab.
It will be appreciated by those skilled in the art that the preferred
embodiment has
been described in some detail but that certain modifications may be practiced
without
departing from the principles of the invention.
11
