Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
1
BOOSTER STEERING LOCK AND LOAD RELIEF CONTROL SYSTEM
FIELD
[0001] The field relates to heavy haul trailers and in particular to a booster
for a heavy haul
trailer.
BACKGROUND
[0002] Canadian Pat. No. 2,756,470 to Wheel Monitor Inc. discloses a
monitoring system to
control liftable or steer axles on a truck or tractor-trailer by monitoring
one or more input data
types selected from the group consisting of speed and direction data, load
data, turn signal data,
engine data, and emergency signal data. Monitoring of the input data is
achieved by sensors
positioned on a fixed axle of the truck or tractor-trailer.
[0003] After processing the input data, a control module controls a lift axle
electrical valving to
lift one or more liftable axles, and also locks the self-steer axle in a
straight position at a
predetermined forward speed or adjusts a pressure on the air suspension of a
steer axle to
equalize an axle bearing weight.
SUMMARY
[0004] All of these aspects herein may be used in any and/or all combinations.
[0005] In a first aspect, a first booster for a trailer system is provided.
The first booster
comprises a frame; at least one self-steer axle coupled to the frame having at
least one pair of
wheels thereon; a coupler securing the frame to a rear end of the trailer
system; a first sensor,
Date Recue/Date Received 2023-04-14
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directly or indirectly coupled to a first wheel of the at least one pair of
wheels, for measuring
direction of rotation information of the first wheel allowing for direction of
the first booster to be
determined when in motion; a steer axle lock that when engaged prevents the at
least one self-
steer axle from self-steering and when not engaged permits the at least one
self-steer axle to self-
steer; a suspension system extending between the frame and the at least one
self-steer axle; and
a control system in communication with the sensor. The control system
comprises instructions .
to: detect a reverse state, when the booster is travelling in a reverse
direction, based on the . , ..c =
direction of rotation information provided by the first sensor; retract the
suspension system when
the reverse state is detected; and engage the steer axle lock when the reverse
state is detected.
100061 In a second aspect, a second booster for a trailer system is provided.
The second booster
comprises a frame; at least one self-steer axle coupled to the frame having at
least one pair of
wheels thereon; a coupler securing the frame to a rear end of the trailer
system; a first sensor,
directly or indirectly coupled to a first wheel of the at least one pair of
wheels, for measuring
direction of rotation information of the first wheel allowing for direction of
the second booster to
.15 be determined when in motion; a steer axle lock that when engaged
prevents the at least one self-
steer axle from self-steering and when not engaged permits the at least one
self-steer axle to self- . =
steer; a suspension system extending between the frame and the at least one
self-steer axle; and a =
control system in communication with the sensor. The control system comprises
instructions to:
detect a forward state, when the booster is travelling in a forward direction,
based on the
direction of rotation information provided by the first sensor; disengage the
steer axle lock when
the forward state is detected; and extend the suspension system when the
reverse state is
detected.
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[0007] In a third aspect, a method for permitting and preventing at least one
self-steer axle
coupled to a frame of a booster from self-steering is provided. The method
comprises the steps
of: measuring direction of rotation information of a first wheel of at least
one pair of wheels that ..' = r
are coupled to the at least one self-steer axle thereby allowing direction of
the booster to be
determined when in motion; detecting a reverse state, when the booster is
travelling in a reverse
direction, based on the direction of rotation information measuring;
retracting a suspension
system extending between the frame and the at least one self-steer axle when
the reverse state is
detected; and engaging the steer axle lock when the reverse state is detected
thereby preventing
the at least one self-steer axle from self-steering.
[0008] In a fourth aspect, a method for permitting and preventing at least one
self-steer axle
coupled to a frame of a booster from self-steering is provided. The method
comprises the steps
of: measuring direction of rotation information of a first wheel of at least
one pair of wheels that =
are coupled to the at least one self-steer axle thereby allowing direction of
the booster to be =
determined when in motion; detecting a forward state, when the booster is
travelling in a forward
direction, based on the direction of rotation information measuring; extending
a suspension
system extending between the frame and the at least one self-steer axle when
the forward state is
detected; and disengaging the steer axle lock when the reverse state is
detected thereby
preventing the at least one self-steer axle from self-steering.
DESCRIPTION OF THE DRAWINGS
[0009] While the invention is claimed in the concluding portions hereof,
example embodiments
are provided in the accompanying detailed description which may be best
understood in
=
= .
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conjunction with the accompanying diagrams where like parts in each of the
several diagrams are
labeled with like numbers, and where: =
1000101 Figures IA to ID are side views of heavy haul multi-axle
trailers of various
configurations;
.
.
[0010] Figure 2 is a side view of a trailer system with a booster;
[0011] Figures 3A to 3C are respectively a top view, a side view, and a rear
view of the booster;
DETAILED DESCRIPTION
[0012] As shown in FIGS. IA to 1D, a heavy haul trailer system 100 may
comprise a number of
axle units, such as a self-steer axle 102, 108 and/or a tandem axle 104, 106,
110. The trailer
system 100 may be hauled using a tractor 600. A number of combinations may be
possible.
100131 The combination of FIG. IA demonstrates a front axle 602 of the tractor
600 being a
.=
single axle with single tires. A drive axle 604 &the tractor is a tandem axle.
The semi-trailer '100
has two axle units: a single self-steer axle 102 in front and a tandem axle
104 in the rear,
[0014] The combination of FIG. 1B demonstrates the front axle 602 of the
tractor 600 also being
a single axle with single tires. However, the drive axle 606 of the tractor is
a tri-drive. The semi-
trailer 100 has two axle units: the single self-steer axle 102 in front and
the tandem axle 104 in
the rear. A weight of the front axle 602 is at least 27 per cent of the tri-
drive.
[0015] The combination of FIG. IC demonstrates the front axle 602 of the
tractor 600 also being
a single axle with single tires. Similar to FIG. 1A, the drive axle 604 of the
tractor is a tandem
=
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axle. The semi-trailer 100 has three axle units: a single self-steer axle 102
in front, a tridem axle
106 in the middle, and a rear self-steer axle 108 in the rear.
100161 The combination of FIG. ID demonstrates the front axle 602 of the
tractor 600 also being
a single axle with single tires. Similar to FIGS. IA and IC, the drive axle
604 of the tractor is a
tandem axle. The semi-trailer 100 has two axle units and one axle group: a
single self-steer axle
102 in front, a quadruple axle 110 in the middle and a single self-steer axle
108 in the rear.
100171 In order for configurability and load management, the trailer system
100 may comprise a -
jeep 200, a trailer 300, and/or a booster 400 as shown in FIG. 2. The
configuration may be _ .
determined in order to allow larger payloads to be carried by the trailer
system 100, one or more
load divider dollies, such as a jeep 200 and/or a booster 400 may be coupled
to the trailer 300.
The trailer 300 may be a removable gooseneck lowboy trailer but may comprise
other types of
trailers. When load divider dollies are rigidly attached to a towing vehicle
600 with no means of
pivoting or turning, the dollies experience tire scrubbing and poor cornering.
[0018] In many instances, the booster 400 has a steering axle 402 to reduce
the tire scrubbing
and to improve cornering.
100191 A typical trailer axle system typically consists of a beam with
spindles on each end for
the wheels. A self-steer axle introduces a pivot on vertical axis between the
beam and the
spindle to allow the spindle to move at an angle relative to the axis of the
beam. It is apparent to
those skilled in the art that the terms "self-steering axle", "steering axle"
and "steer axle" refer to
.. a "self-steer axle".
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[0020] Although the booster 400 may have the steering axle 402, Safe-
Productive-Infrastructure-
Friendly (SPIF) vehicle testing in Ontario, Canada has revealed that the
steering axle 102 behind
a primary axle group 604, 606, such as those shown in FIGS. 1A to ID, may
induce an instability
at high speeds with increased off-tracking. The instability may apply
particularly to 5 to 6 axle
semi-trailers. A solution to the instability has been to mandate in Ontario by
regulations 413/05
"Vehicle Weights and Dimensions ¨ For Safe, Productive and Infrastructure-
Friendly Vehicles",
dated September 29, 2017, that a lock for the self-steer axles 102, 108 of the
trailer 100 engage
automatically at 60-kilometers per hour (km/h) for four designated tractor-
trailer combinations as
shown in FIGS. 1A to 1D. Each of the combinations demonstrate a tractor 600
and a single semi-
trailer system 100.
[0021] Specifically, the Ontario regulations specify that for FIGS. lA and 1B,
if an axle spread
of the tandem axle 104 of the semi-trailer 100 exceeds 1.85-m, the tractor 600
and trailer system
100 combination must be equipped with an automatic device (not shown) that
locks the self-steer
axle 102 in the straight ahead position when the combination is travelling at
a speed over 60-
km/h. Similarly, the tractor 600 and trailer system 100 combination shown in
FIGS. IC and 1D
must be equipped with the automatic device that locks a rearmost self-steer
axle 108 in the
straight-ahead position when the combination is travelling at a speed over 60-
km/h.
[0022] Similarly, to the described-above problems associated with the trailer
systems shown in
FIGS. lA to 1D, current heavy haul boosters, such as the booster 400 shown in
FIG. 2, suffer
from their rigid attachment to trailer and a high-speed instability, known in
the industry as
"booster dance-. This instability may become severe enough to cause the
booster to detach from
the trailer at speed, potentially causing injury or death. By attempting to
apply the regulations to
Date Regue/Date Received 2023-04-14
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the booster 400, complications may occur since the booster 400 is a separate
vehicle that is
rigidly attached to the semi-trailer 300.
100231 Numerous systems to auto-lock a self-steer axle have been developed for
many trailer
systems 100, without a booster, in an effort to remedy the problems described
above. Some of
these systems are described in Canadian Pat. No. 2,756,470 to Wheel Monitor
Inc. and the
references discussed therein. For example, in many trailer systems 100,
without a booster 400, a
velocity and a direction sensor installed on a non-steering (or non-lifting)
fixed axle, are
employed to determine whether a self-steer axle should be prevented or
permitted to self-steer.
100241 It has been found, however, that the prior art systems, suffer from
their applicability to
boosters such as the booster 400 shown in FIG. 2 as there are no fixed axles
to attach a velocity
and direction sensor onto. Typically, the prior art employs sensors on fixed
axles as lift-axles are
lifted (to alleviate a load on the axle) when a trailer system is reversing
thereby rendering the lift-
axles and wheels coupled thereon inappropriate to couple sensors onto as such
sensors would not
be able to detect forward motion. The closest fixed axle of a booster, such as
the booster 400
shown in FIG. 2, is on an adjacent vehicle thereby rendering it impractical to
use. Locking and
unlocking of a self-steer axle on a booster therefore typically proceeds via a
manual operation
where a user manually operate a switch to engage or disengage a lock pin to
respectively lock or
unlock a self-steer axle.
100251 What is needed, therefore, is a system that is relatively simple and
robust in construction
and considers boosters with only one or more self-steer axles and no fixed
axles to attach
velocity and direction sensor onto.
Date Recue/Date Received 2023-04-14
=
8
=.
[0026] The present invention contemplates that since the booster 400 shown in
FIG. 2 comprises = =
only one or more self-steer axle(s) 402, a velocity sensor and direction
sensor may be located on
the self-steer axle 402 rather than a non-steering axle. Rather than lifting
an axle off the ground
to alleviate a load carried by the axle, some aspects of the present invention
instead contemplate
compressing a suspension system coupled to a self-steer axle allowing a wheel
coupled to a self-
steer axle to remain on the ground while reducing a load carried by the
booster 400 when
traveling in reverse. This may allow a sensor, coupled to the wheel, to still
monitor speed and
rotation direction of the wheel so that forward movement and speed can be
detected and
monitored after reverse motion is detected.
[0027] 'For example, when the booster 400 is traveling in reverse, the present
invention may
automatically lock or secure the steer axle 402. Preferably, the present
invention also compresses
a suspension system, if necessary, extending between a frame of the booster
400 and the self-
steer axle 402 thereby reducing a load carried by the booster 400 when
traveling in reverse.
100281 When travelling forward, the present invention may automatically unlock
the self-steer
axle 402 allowing it to be steerable. Preferably, the present invention also
expands a suspension
system, if necessary, extending between a frame of the booster 400 and the
self-steer axle 402
thereby increasing a load on the booster 400 when traveling forward.
[0029] When travelling forward, the present invention may also automatically
lock the self-steer
axle 402 when the booster 400 reaches a predetermined speed (for example, 60
km/hr) when
travelling forward and automatically unlock the self-steer axle 402 when the
booster 400 is
below the predetermined speed.
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[0030] An example of the booster 400 with a single self-steer axle 402 may be
shown in FIGS.
3A to 3C. The booster 400, also known as a "lishmouth booster", comprises a
self-steer axle 402
coupled to a frame 404. The frame 404 may be generally rectangular in shape
and/or may
comprise one or more platforms. The axle 402 may comprise one or more pairs of
wheels and
.. their associated tires. At one end of the frame 404 may be one or more
couplers 406, 408
configured to couple to a rear end of the trailer 300. A pair flack legs 410
coupled to the frame
404 may be used to retain the booster 400 in a level position when the booster
400 is decoupled
from the trailer 300. A pneumatic suspension system may be provided by a
controller 412
coupled to an air tank 414. In one aspect, the pneumatic suspension system may
have one or
more air bags. The description herein is merely an example and those skilled
in the art upon
reviewing the description maybe aware of numerous suspension system
arrangements and means
suitable for implementation. A spare tire assembly 416 may also be coupled to
a top surface of
the frame 404.
100311 At least one sensor is provided (not shown to avoid obscuring other
components) for
measuring direction of rotation information and/or speed of rotation
information of a wheel
coupled to the axle 402. For example, a Hall-Effect sensor may be employed
wherein the sensor,
provided on a block attached to the axle, faces an exciter ring mounted on the
wheel hub. When
the hub rotates, the teeth of the exciter ring pass across the face of the
sensor thereby allowing
the sensor to determine speed and direction of rotation of the wheel. Numerous
sensors for
.. measuring direction of rotation information and/or speed of rotation
information of a wheel that
could be employed within the scope of the description herein would be known to
those skilled in
the art. For example, several sensors are described in Canadian Pat, No.
2,756,470 to Wheel
Monitor Inc. and the references mentioned therein. In some aspects, there may
be more than one
Date Recue/Date Received 2023-04-14
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sensor employed for measuring direction of rotation information and/or speed
of rotation
information of one or more wheels coupled to the axle 402.
100321 A steer axle lock is provided that when engaged prevents the self-steer
axle 402 from
self-steering and when not engaged permits the self-steer axle 402 to self-
steer. Numerous steer-
axle lock assemblies for preventing and permitting a self-steer axle 402 to
self-steer that could be
employed within the scope of the description herein would be known to those
skilled in the art.
For example, spindle ends of a steering axle are typically joined by a tie rod
to ensure they rotate
together. To lock a steer axle, a latch that is moved by an air actuator is
moved into position to
engage with the center of the tie rod, thereby preventing movement.
[0033] In one aspect, a steer axle lock includes a small air pot is provided
that will pivot a lock
down component onto a locking plate when the wheels are centered. Such a steer
axle lock
assembly would be known to those skilled in the art. For example, Dexter
manufactures such
assemblies ¨ such as the Ingersoll Axle.
100341 The information measured by the sensor is provided to a controller 412
located on the
booster 400 which may lock the steering axle 402 of the booster 400 at highway
speeds in order
to improve the high-speed performance of the booster 400 or when the booster
400 is traveling in
reverse.
[0035] In some aspects, upon receiving infonnation from the sensor, the
controller 412 may
detect a reverse state, when the booster is travelling in a reverse direction,
based on the direction
of rotation information provided by the sensor. Upon detection of a reverse
state, the controller
412 may generate instructions to deflate the pneumatic suspension system and
engage the steer
Date Recue/Date Received 2023-04-14
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axle lock thereby locking the self-steer axle 402 as the booster travels in
reverse. Deflating the
pneumatic suspension system may decrease the distance between the self-steer
402 axle and the . =
frame 404 thereby reducing a load carried by the booster 400.
[0036] Tri one aspect, the steer axle lock, when engaged, prevents the self-
steer axle 402 from
self-steering only when the wheels are positioned to allow movement of the
booster 400 in a
direction that is parallel to the longitudinal axis of the booster 400. In
other words, the wheels are
locked when in a straight configuration as the booster 400 travels in reverse.
[0037] In some aspects, upon receiving information from the sensor, the
controller 412 may
detect a forward state, when the booster is travelling in a forward direction,
based on the
direction of rotation information provided by the sensor. Upon detection of a
forward state, the
controller 412 may generate instructions to disengage the steer axle lock; and
inflate = the .
pneumatic suspension system when the forward state is detected. Inflating the
pneumatic
suspension system may increase the distance between the self-steer 402 axle
and the frame 404
thereby increasing a load carried by the booster 400.
[0038] It should be noted that to detect a reverse state, a typical automatic
control system found
on trailers 300 may engage a lock pin. However, such typical automatic control
systems detect
forward movement using a fixed axle to exit a reverse state. This detection is
not possible with
the booster 400 because the nearest fixed axle is located on the adjacent
trailer 300 making the
fixed axle impractical to use. As previously discussed, some solutions require
an operator to
manually engage and disengage a lock pin for locking and unlocking a self-
steer axle 402.
[0039] The present system as described herein detects forward motion by
deflating the =
pneumatic suspension system and foregoing the lifting the axle(s) 402 off the
.ground. The
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deflation of the pneumatic suspension system may relieve the axle(s) 402 of
all weight except for
the unsprung mass thereby allowing ease of reverse operation. As the wheels
remain in contact .
with the ground, forward motion may be detected by the sensor by a forward
rotation of the / :==
wheels thereby trigging the unlocking of the self-steer axle 402 and the re-
inflating of the
suspension.
100401 In some aspects, upon receiving information from the sensor, the
controller 412 may
detect a high-speed forward state, when the booster is travelling in forward
direction at a speed
that is equal to or greater than a predetermined speed, based on the speed of
rotation information
and the direction of rotation information provided by sensor. Upon detection
of a high-speed
forward state, the controller 412 may generate instructions to engage the
steer axle lock thereby
preventing the self-steer axle 402 from self-steering. This may occur in
situations such as when
the booster 400 is traveling at a high speed on a highway (for example at 60
km/hr and above). In
one aspect, the steer axle lock, when engaged, prevents the self-steer axle
402 from self-steering .
only when the wheels are positioned to allow movement of the booster 400 in a
direction that is
parallel to the longitudinal axis of the booster 400.
[0041] In some aspects, upon receiving information from the sensor, the
controller 412 may
detect a low-speed forward state, when the booster is travelling in forward
direction at a speed
that is less than a predetermined speed, based on the speed of rotation
information and the
direction of rotation information provided by sensor. Upon detection of a low-
speed forward
state, the controller 412 may generate instructions to disengage the steer
axle lock thereby
allowing the self-steer axle 402 to self-steer. This may occur in situations
such as when the
booster 400 is traveling at a low speed (for example at speeds lower than 60
km/hr).
. .
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[0042] Components, such as, but not limited to valves and switches, may be
adjusted so that
= instructions generated by the controller are carried out. Many different
types of means and
arrangements suitable for carrying out the foregoing instructions of the
controller 412. are ,
possible within the scope of the present invention and would be known to those
skilled in the art:
For example, in some aspects of the present invention, the controller 412
receives speed and
direction inputs from the sensor, processes the information and sends the
applicable signals to
one or more solenoid valves. The solenoid valves will upon activation deliver
pneumatic
pressure to the steer lock actuator and/or the suspension air bags. Upon
removal of the processor
signal, the solenoid valve will revert to a preferred state and exhaust the
air supplied to the
suspension or steer lock.
[0043] In operation, the controller 412 ether detects a reverse state, a
forward state, a high-speed
forward state or a low-speed forward state.
,
100441 If a reverse state is detected, the controller 412 generates
instructions that ensure the steer ..=
axle lock is engaged to prevent the self-steer axle 402 from self-steering,
and that the suspension
system is deflated (or compressed) to a predetermined pressure (or height)
such that the load
carried by the booster is decreased. A reverse state may be detected following
the detection of
forward state or a state where the booster 400 is stationary.
[0045] If a forward state is detected, the controller 412 generates
instructions that ensure the
steer axle lock is disengaged to allow the self-steer axle 402 to self-steer,
and that the suspension
system is inflated (or extended) to a predetermined pressure (or length) such
that the load carried
by the booster is increased. A forward state may be detected following the
detection of reverse
=
state or a state where the booster 400 is stationary.
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[0046] If a high-speed forward state is detected, the controller 412 generates
instructions that
ensure the steer axle lock is engaged to prevent the self-steer axle 402 from
self-steering. A high- =
.=
speed forward state may be detected following the detection of low-speed
forward state.
[0047] If a low-speed forward state is detected, the controller 412 generates
instructions that
ensure the steer axle lock is disengaged to allow the self-steer axle 402 to
self-steer. A low-speed
forward state may be detected following the detection of high-speed forward
state.
100481 The foregoing is considered as illustrative only of the principles of
the invention. Further,
since numerous changes and modifications will readily occur to those skilled
in the art upon
review of the present description and drawings, the foregoing is not desired
to limit the invention
to the exact construction and operation shown and described, and accordingly,
all such suitable
changes or modifications in structure or operation which may be resorted to
are intended to fall =
,
. .
within the scope of the claimed invention.
.
.
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