U.S. patent application number 10/083988 was filed with the patent office on 2002-06-27 for traction-enhancing system for use with motor vehicles.
This patent application is currently assigned to James B. Skarie. Invention is credited to Skarie, Christopher J., Skarie, James B., Skarie, Loren P., Skarie, Paul R..
Application Number | 20020079707 10/083988 |
Document ID | / |
Family ID | 22887439 |
Filed Date | 2002-06-27 |
United States Patent
Application |
20020079707 |
Kind Code |
A1 |
Skarie, James B. ; et
al. |
June 27, 2002 |
Traction-enhancing system for use with motor vehicles
Abstract
A vehicle-mounted device and method for delivering a traction
enhancing material to a road surface directly in front of one or
more tires is disclosed. The device delivers the traction enhancing
material when an electronic controller detects a loss of traction.
The device uses an air duct to collect air incident on the vehicle
and direct the air to the road surface. The device further
comprises a hopper to hold the traction enhancing material. The
hopper is coupled to the air duct at an aperture. When activated, a
valve assembly selectively opens and closes the aperture in
response to controller commands. When opened, the traction
enhancing material accelerates from the hopper into the duct and
becomes entrained in the air stream where it is then delivered to
the road surface. Once delivered, the traction enhancing material
is introduced between the tires and the road surface to effectively
increase the coefficient of friction therebetween.
Inventors: |
Skarie, James B.;
(Minnetonka, MN) ; Skarie, Christopher J.;
(Audubon, MN) ; Skarie, Loren P.; (Vergas, MN)
; Skarie, Paul R.; (Minnetonka, MN) |
Correspondence
Address: |
SCHWEGMAN, LUNDBERG, WOESSNER & KLUTH, P.A.
P.O. BOX 2938
MINNEAPOLIS
MN
55402
US
|
Assignee: |
James B. Skarie
|
Family ID: |
22887439 |
Appl. No.: |
10/083988 |
Filed: |
February 25, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10083988 |
Feb 25, 2002 |
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09235930 |
Jan 22, 1999 |
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6371532 |
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Current U.S.
Class: |
291/38 |
Current CPC
Class: |
B60B 39/086 20130101;
B60T 8/56 20130101; B60B 39/025 20130101 |
Class at
Publication: |
291/38 |
International
Class: |
B61C 015/10 |
Claims
What is claimed is:
1. A traction enhancing device for use with a moving vehicle, the
device comprising: an air duct for receiving air incident on the
vehicle; a storage hopper adapted to hold a traction enhancing
material; a valve assembly intermediate the hopper and the air duct
wherein the valve assembly selectively permits communication
between the hopper and the air duct; and a control system for
selectively activating the valve assembly in response to one or
more control inputs.
2. The traction enhancing device of claim 1 wherein the hopper
couples to the air duct at an aperture.
3. The traction enhancing device of claim 1 wherein the air duct
further comprises: an air scoop for receiving the air; a nozzle for
directing the air and traction enhancing material to a tire/road
interface; and an elbow intermediate the air scoop and the
nozzle.
4. The traction enhancing device of claim 2 wherein the valve
assembly comprises a movable valve member selectively covering the
aperture.
5. A device for distributing a traction enhancing material to a
portion of road surface generally forward of one or more tires of a
moving vehicle, the device comprising: air duct attached to the
vehicle, wherein the air duct defines an interior passageway, the
air duct having: a scoop for receiving air incident on the moving
vehicle; a nozzle for directing the air to the portion of road
surface; and one or more elbows intermediate the scoop and nozzle,
the elbow providing a smooth transition for air traveling from the
scoop to the nozzle; a storage hopper adapted to store a volume of
traction enhancing material wherein the hopper has an outlet
channel; a valve assembly for selectively opening and closing an
aperture defined by an intersection of the outlet channel and the
air duct, wherein the valve assembly permits movement of the
traction enhancing material from the hopper into the air duct where
it becomes entrained with the air; and a control system for
selectively activating the valve assembly in response to one or
more control inputs.
6. The device of claim 5 wherein the scoop is located slightly
forward of a front end of the vehicle.
7. The device of claim 5 wherein the scoop has a flared mouth
having a mouth diameter.
8. The device of claim 7 wherein the air duct has a duct diameter
less than the mouth diameter.
9. The device of claim 8 wherein the nozzle further comprises: an
enlarged, annular portion having a nozzle diameter larger than the
duct diameter; and an internal tubular portion, the tubular portion
having a one or more openings that permit the air to expand from
the tubular portion into the annular portion but are insufficient
in size to permit the passage of the traction enhancing material
from the tubular portion into the annular portion.
10. The device of claim 9 wherein the openings on the tubular
portion comprise a series of holes.
11. The device of claim 9 wherein the openings on the tubular
portion comprise a series of slots.
12. The device of claim 5 wherein the nozzle further comprises a
nozzle aiming mechanism.
13. The device of claim 5 wherein the hopper additionally
comprises: a removable cover; a heat trace proximate the outlet
channel and the aperture to prevent freezing of the traction
enhancing material; and a level sensor to determine the volume of
traction enhancing material present within the hopper.
14. The device of claim 5 wherein the control system further
comprises: a microprocessor-based module for receiving and
processing the control inputs; and a first control output for
selectively opening and closing the valve assembly in response to
the control inputs.
15. The device of claim 14 wherein the control system further
comprises a second control output for selectively aiming the
nozzle.
16. The device of claim 5 wherein the control inputs comprise: one
or more accelerometers operatively connected to the control system;
one or more wheel speed sensors operatively connected to the
control system; and one or more steering wheel position sensors
operatively connected to the control system.
17. The device of claim 5, wherein the traction enhancing material
comprises sand.
18. The device of claim 5 wherein the valve assembly comprises: a
valve plate disposed over the aperture, the valve plate movable
between an open and a closed position; a displacing device for
displacing the valve plate between the open and closed positions; a
retaining member extending around a periphery of the aperture; and
a gasket extending around the periphery of the aperture.
19. An apparatus for distributing a traction enhancing material to
a road surface generally forward of one or more tires of a moving
vehicle, the apparatus comprising: a source of compressed gas; and
a discharge unit, wherein the discharge unit can selectively
discharge a projectile to the road surface to improve traction and
wherein the discharge unit develops energy from the source of
compressed gas.
20. The apparatus of claim 19 wherein the projectile is a granular
material encased within a shell, wherein the shell breaks open upon
contact with the road surface.
21. The apparatus of claim 20 wherein the projectile is a glass
sphere, wherein the sphere shatters and disperses upon contact with
the road surface.
22. A method of dispensing a traction enhancing material to a road
surface generally forward of one or more tires of a moving vehicle
having an anti-lock brake system, wherein the method comprises:
collecting air incident on the moving vehicle; accelerating the air
through an air duct; sensing a loss of traction between the one or
more tires and the road surface beyond a predefined threshold
level; selectively dispensing a traction enhancing material into
the air duct; and directing the accelerated air and entrained
traction enhancing material to the road surface forward of the one
or more tires.
23. The method of claim 22 further comprising intermittently
rotating the one or more tires in response to the anti-lock brake
system, thereby trapping the traction enhancing material between
the tire and the road surface and thus increasing traction.
24. The method of claim 22 further comprising ceasing dispensation
of the traction enhancing material upon sensing tire traction has
returned within the predefined threshold.
25. A method of dispensing a traction enhancing material to a road
surface generally forward of one or more tires of a vehicle having
an anti-lock brake system, wherein the method comprises:
determining a wheel speed; determining a ground speed; comparing
the wheel speed to the ground speed; opening a valve in
proportional response to the ground speed; dispensing a traction
enhancing material through the valve to the road surface, wherein
the traction enhancing material increases traction; determining
when the ground speed matches the wheel speed; and closing the
valve.
26. The method of claim 25 further comprising: reading a first
accelerometer signal; and calculating the ground speed based on the
first accelerometer signal.
27. The method of claim 26 further comprising: reading a second
accelerometer signal; reading a steering wheel position signal;
comparing the steering wheel position signal to the second
accelerometer signal; opening the valve in proportional response to
the ground speed; dispensing the traction enhancing material
through the valve to the road surface, wherein the traction
enhancing material increases traction; determining when the
steering wheel position signal matches the second accelerometer
signal; and closing the valve.
28. The method of claim 25 further comprising providing a warning
indication to an operator within the vehicle that the valve is
opened.
29. The method of claim 27 further comprising: generating a
plurality of control inputs based on the wheel speed, ground speed,
first accelerometer signal, second accelerometer signal, and
steering wheel position signal; and processing the plurality of
control inputs with a system controller.
30. The method of claim 25 further comprising: providing a hopper
to retain the traction enhancing material; sensing a volume of
material within the hopper; and providing a warning indication when
the volume of material drops below a threshold value.
31. The method of claim 27 further comprising: providing a memory
device; receiving one or more of the first accelerometer signal,
the second accelerometer signal, and the steering wheel position
signal into the memory device; and storing the signals in the
memory device for a predetermined period of time, wherein the
signals may be subsequently extracted from the memory device.
32. The method of claim 29 further comprising: providing a cellular
telephone and a global positioning system operatively connected to
the system controller; notifying a remote station with the cellular
telephone when one or more predefined conditions is satisfied; and
transmitting the vehicle coordinates calculated by the global
positioning system to the remote station.
33. An automobile comprising: a chassis; one or more drive wheels
operatively coupled to the chassis; a power source operatively
coupled to the chassis to provide power to the one or more drive
wheels; one or more steerable wheels operatively coupled to the
chassis; a brake system for stopping the one or more drive wheels
and the one or more steerable wheels; and a traction enhancing
device mounted to the chassis proximal the one or more drive wheels
or the one or more steerable wheels, the device comprising: a
storage hopper adapted to hold a traction enhancing material; an
air duct for receiving air incident on the automobile, the air duct
including an air scoop for receiving the air and a nozzle for
directing the air to a tire/road interface; a valve assembly
intermediate the hopper and the air duct wherein the valve assembly
selectively permits communication between the hopper and the air
duct wherein the traction enhancing material becomes entrained with
the air; and a control system for selectively activating the valve
assembly in response to one or more control inputs.
34. A projectile for use with a traction enhancing apparatus
attached to a moving vehicle, the projectile comprising a sphere
adapted to be accelerated by the traction enhancing apparatus.
35. The projectile of claim 34 wherein the sphere comprises a shell
encasing a granular substance.
36. The projectile of FIG. 35 wherein the shell comprises a gelatin
material.
37. The projectile of FIG. 36 wherein the gelatin shell is hardened
such that it ruptures on impact with a road surface and disperses
the granular material encased therein.
38. The projectile of claim 34 wherein the sphere comprises a glass
material that shatters on impact with a road surface.
Description
TECHNICAL FIELD
[0001] The present invention relates to a device for delivering
sand to a road surface and, more particularly, to a vehicle-mounted
device that automatically delivers a traction enhancing material
proximate one or more wheels of a vehicle.
BACKGROUND OF THE INVENTION
[0002] In almost all climates, slippery roads pose a potential
burden to drivers. In colder climates, ice formation on the roads
can create treacherous driving conditions. In warmer weather where
icy roads are not an issue, wet roads have a similar albeit reduced
adverse effect on tire traction.
[0003] Loss of traction due to wet or icy roads is attributable to
a change in the coefficient of friction (COF) between the tire and
the road surface. On dry roads, the COF is adequate to permit
traction for accelerating, decelerating, and turning. However, when
the pavement is wet or icy, the COF drops and the vehicle's
performance characteristics become more unpredictable. In
particular, the vehicle is more susceptible to tire spin during
acceleration and tire lock during braking and turning. Although
tire slippage during acceleration is a problem, it does not pose
the danger inherent with decreased stopping ability. While the
present invention is advantageous during both tire slip (during
acceleration) and tire skid (during deceleration) situations, it is
directed primarily to a traction enhancing device and method for
assisting a vehicle in decelerating and stopping.
[0004] Various devices have been developed to improve vehicle
traction on ice or other slippery road surfaces. The most common
method known is to dispense granular salt or sand directly to the
road surface. While effective in providing traction, salt is highly
corrosive to vehicles and cumulative use can damage road surfaces.
Sand, on the other hand, provides the traction benefits of salt
without the harmful side effects.
[0005] Sand is typically dispensed by a municipal dump truck,
usually following a winter storm. Unfortunately, there is a period
of time after the storm in which the roads remain untreated. This
is particularly evident on smaller roads and side streets which may
not be treated for quite some time. In addition to this delay, sand
coverage of a road surface may be spotty due to the operation of
conventional sand spreaders. For these reasons, municipal sand
dispensing systems are not completely effective.
[0006] In an attempt to overcome these problems, sand dispensing
systems that attach directly to an automobile have been developed.
These systems are advantageous over municipal spreaders in that
they are integral to the vehicle. Thus, they can dispense sand at
any time and in any place. For example, U.S. Pat. No. 5,118,142
discloses a traction device that disperses sand to the vicinity of
one or more tires of an automobile. While effective in delivering
sand to the tire/road interface, the '142 patent requires manual
activation and requires a steady stream of delivered sand.
Depending on the speed of the car, a large volume of sand may be
needed in order to bring the car to a complete stop.
[0007] U.S. Pat. No. 5,582,441 discloses another system comprising
a sand reservoir incorporated into the front bumper of an
automobile. A blower system dispenses the sand in a wide pattern
forward of the vehicle. While requiring less sand than other sand
dispensing devices, the '441 system still delivers more sand than
is necessary. Stated alternatively, the wide sand dispersion
pattern results in excessive sand deposited on the road, some of
which is not utilized by the vehicle tires. Additionally, the '441
patent requires a blower source in order to propel the sand.
[0008] Accordingly, the current traction enhancing devices have
disadvantages that limit their commercial acceptance. A traction
enhancing device that is fully automatic and applies only the
amount of traction enhancing material necessary to adequately
increase the COF is highly desirable.
SUMMARY OF INVENTION
[0009] A traction enhancing device and method are disclosed. The
traction enhancing device, in one embodiment, comprises an air duct
for receiving air incident on the vehicle; a storage hopper adapted
to hold a traction enhancing material; a valve assembly
intermediate the hopper and the air duct wherein the valve assembly
selectively permits communication between the hopper and the air
duct; and a control system for selectively activating the valve
assembly in response to one or more control inputs.
[0010] A method of dispensing a traction enhancing material to a
road surface generally forward of one or more tires of a moving
vehicle wherein the vehicle has an anti-lock brake system is also
disclosed. In one embodiment, the method includes collecting air
incident on the moving vehicle; accelerating the air through an air
duct; sensing a loss of traction between the one or more tires and
the road surface beyond a predefined threshold level; selectively
dispensing a traction enhancing material into the air duct; and
directing the accelerated air and entrained traction enhancing
material to the road surface forward of the one or more tires.
[0011] In one embodiment, the air duct has an air scoop for
receiving air and a nozzle for directing the received air to a
tire/road interface. The scoop may also include an elbow
intermediate the air scoop and the nozzle.
[0012] The hopper may couple to the air duct at an aperture.
Furthermore, the aperture may be selectively covered by a valve
assembly having a movable valve member.
[0013] In another embodiment, a device for distributing a traction
enhancing material to a portion of road surface generally forward
of one or more tires of a moving vehicle is disclosed. The device
includes an air duct defining an interior passageway, wherein the
air duct has: a scoop for receiving air incident on the moving
vehicle; a nozzle for directing the air to the road surface; and
one or more elbows intermediate the scoop and nozzle. The elbow may
provide a smooth transition for air traveling from the scoop to the
nozzle. The device may also include a storage hopper adapted to
store a volume of traction enhancing material the hopper has an
outlet channel. Additionally, the apparatus includes a valve
assembly for selectively opening and closing an aperture defined by
an intersection of the outlet channel and the air duct. The valve
assembly permits movement of the traction enhancing material from
the hopper to the air duct where it becomes entrained with the air.
Furthermore, the apparatus includes a control system for
selectively activating the valve assembly in response to one or
more control inputs.
[0014] In yet another embodiment, the scoop has a flared mouth and
is located slightly forward of the front end of the vehicle. The
interior passageway may have a reduced diameter and the nozzle may
include an enlarged, annular portion and an internal tubular
portion. The internal tubular portion may have one or more openings
that permit the air to expand from the tubular portion into the
annular portion but prevent the passage of the traction enhancing
material from the tubular portion into the annular portion. In one
embodiment, the openings are holes. In another embodiment, the
openings are slots.
[0015] The hopper may have a removable cover and a level sensor.
Proximate the channel and aperture, the hopper may also include a
heat trace to prevent freezing of the traction enhancing
material.
[0016] The control system may include a microprocessor-based module
for receiving and processing the control inputs. It may also have a
first control output for selectively opening and closing the valve
assembly in response to the control inputs and a second control
output for selectively aiming the nozzle. The controller may
monitor various control inputs including one or more accelerometers
operatively connected to the control system; one or more wheel
speed sensors operatively connected to the control system and one
or more steering wheel position sensors operatively connected to
the control system.
[0017] In yet another embodiment, an apparatus for distributing a
traction enhancing material to a portion of road surface generally
forward of one or more tires of a moving vehicle is described. The
apparatus comprises a source of compressed gas; and a discharge
unit, wherein the discharge unit can selectively discharge a
projectile to the road surface and wherein the discharge unit
develops energy from the source of compressed gas.
[0018] In still yet another embodiment, the method may include
intermittently rotating the tire in response to the anti-lock brake
system, thereby trapping a traction enhancing material between a
tire and a road surface and thus increasing traction.
[0019] In another embodiment, a method of dispensing a traction
enhancing material to a portion of road surface generally forward
of one or more tires of a vehicle having an anti-lock brake system
is disclosed wherein the method comprises determining a wheel
speed; determining a ground speed; comparing the wheel speed to the
ground speed; opening a valve in proportional response to the
ground speed; dispensing a traction enhancing material through the
valve; determining when the ground speed matches the wheel speed;
and closing the valve.
[0020] Accordingly, the present invention provides an effective
traction device that can be used on a variety of vehicles. By
taking advantage of the vehicle anti-lock brake system, the present
invention may provide improved traction with minimal dispersion of
sand. Additionally, the present invention takes advantage of air
incident on the vehicle rather than a separate power source to
disperse the traction enhancing material. Furthermore, the system
is fully automatic and requires no driver input in order to
operate.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The invention described herein will be further characterized
with reference to the drawings, wherein:
[0022] FIG. 1 is a diagrammatic side elevational view of a traction
enhancing device in accordance with one embodiment of the present
invention as it would be installed on an automobile;
[0023] FIG. 2 is detailed side elevational view of a traction
enhancing device in accordance with another embodiment of the
present invention as it would be installed on an automobile;
[0024] FIG. 3 is an enlarged front sectional view of the traction
device of FIG. 2 taken along lines 3-3 of FIG. 2;
[0025] FIG. 4 is a diagrammatic front elevational view of the
traction enhancing device of FIG. 2;
[0026] FIG. 5 is a cross sectional side view illustrating an
alternative embodiment of the nozzle portion of the traction
enhancing device of FIG. 2;
[0027] FIG. 6 is an end view of the nozzle portion of FIG. 5;
[0028] FIG. 7 is an enlarged partial side view of the valve plate
and aperture of FIG. 2;
[0029] FIG. 8 is a partial top plan view of the aperture of FIG. 2
showing the gasket geometry;
[0030] FIG. 9 is a enlarged, partial front elevational view of the
valve plate of FIG. 2;
[0031] FIG. 10 is flowchart describing the events that occur during
operation of a controller in accordance with one embodiment of the
present invention;
[0032] FIG. 11 is a diagrammatic view of the system controller of
FIG. 10;
[0033] FIG. 12 is a dashboard indicator panel in accordance with
one embodiment of the invention;
[0034] FIG. 13 is a diagrammatic view of another embodiment of the
traction enhancing device in accordance with the present
invention;
[0035] FIG. 14 is an enlarged sectional view of a portion of the
device of FIG. 13; and
[0036] FIG. 15 is a projectile in accordance with one embodiment of
the invention for use with the device of FIG. 13.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] In the following detailed description of the preferred
embodiments, reference is made to the accompanying drawings which
form a part hereof, and in which are shown by way of illustration
specific embodiments in which the invention may be practiced. It is
to be understood that other embodiments may be utilized and
structural changes may be made without departing from the scope of
the present invention.
[0038] Referring to FIG. 1, a first embodiment of a traction device
200 is shown as it may appear when mounted to the front of a
vehicle 100. For simplicity, the invention is described herein with
reference to a pair of front wheels 102 of a conventional
automobile. However, those skilled in the art will realize that the
traction device of the present invention could also be used in
conjunction with the rear wheels. Likewise, the present invention
could be adapted to other multi-wheeled vehicles including but not
limited to pick-up trucks, semi-tractors, and utility vehicles.
With slight modifications, the device 200 could also be used with
aircraft and railroad vehicles.
[0039] Still referring to FIG. 1, the device 200 comprises an air
duct or conduit 202 attached within a wheel well of the vehicle. A
series of support member 203a, 203b, and 203c support the air duct
in place. The air duct 202 further comprises an air scoop 204, and
an air nozzle 206. In one embodiment, the air scoop 204 extends
slightly forward of a vehicle bumper 104. The purpose of the air
scoop 204 is to collect a stream of incident air 201 as the vehicle
travels in a forward direction.
[0040] The air duct 202 further includes an elbow 208. The elbow
208 joins the scoop 204 and the nozzle.206. It provides a smooth
transition from the generally fore-and-aft direction of the scoop
to the more downward and outward direction of the nozzle.
[0041] Referring now to FIG. 2, a more detailed, cross-sectional
view of the device 200 is shown. A hopper 300 is operatively
coupled to the air duct 202 at an aperture 214. A valve assembly
302 is located at the aperture 214. The hopper 300 holds a volume
of traction enhancing material 304. To simplify the discussion, the
traction enhancing material 304 will be hereinafter described as
sand. However, other granular materials, including but not limited
to, #1 grit or crushed granular glass are equally within the scope
of the invention. As described in detail below, when the traction
device 200 is activated, sand is released into the duct 202 by the
valve assembly 302 and becomes entrained or intermixed with the air
201. The entrained sand 304 travels through the nozzle 206 and is
dispersed forward in an area 106 forward of a tire/road interface
108 (see FIG. 1).
[0042] A remotely located control system or controller 400 (shown
diagrammatically in FIG. 11) constantly monitors various vehicle
operating parameters which are further described below. When the
controller 400 senses that the tire 102 has lost traction, the
controller can activate the valve assembly 302 to initiate sand
delivery.
[0043] Due to the cyclic braking characteristics of the vehicle's
anti-lock brake system, sand 304 delivered to the road can migrate
beneath the tire 102 to the tire/road interface 108 as the tire 102
incrementally rotates. That is, as the anti-lock brake system
cycles the brakes, the tire 102 rotates. As it rotates, the tire
102 engages the sand dispensed by the nozzle 206 and draws it
between the tire 102 and the road surface. With the sand trapped
between the tire and the slippery road, the COF increases
substantially. Thus, the vehicle is better able to stop. Several
parameters are simultaneously monitored to determine how much sand
is delivered and for how long. When the controller 400 determines
that the vehicle has regained traction, it commands the valve
assembly 302 closed, discontinuing sand delivery.
[0044] With this description, attention will now be focused on
various components of one exemplary embodiment of the traction
device 200.
The Air Duct
[0045] Referring to FIGS. 1 and 2, the air duct 202 is shown in
varying degrees of detail. Referring to FIG. 1, a partial section
view of the vehicle 100 depicts the air duct 202 of the present
invention as it might appear when mounted to the vehicle forward of
the tire 102. Typically, although not exclusively, the traction
enhancing device 200 is mounted forward of each front wheel 102 of
the vehicle 100. While this configuration does not provide sand
directly to the rear wheels, sand dispersed ahead of the front
wheels will also assist the rear wheels as the vehicle travels
forward. However, where necessary, the device 200 may also be
placed at the rear wheels with minimal modifications. The air duct
202 provides a mechanism for passively receiving a stream of air
201 and delivering that stream of air with the traction enhancing
material 304 entrained therein to the road surface directly in
front of the tire 102.
[0046] Referring specifically to FIG. 1, the air scoop 204 is
formed on the forward end of the air duct 202. The air scoop 204
has an opening or mouth 205 which, in one embodiment, is located
slightly forward of the leading surface of the vehicle bumper 104.
The mouth 205 is placed forward of the bumper to improve the
dynamic airflow characteristics into the scoop 204. Ideally, the
mouth 205 is placed to provide smooth and continuous airflow into
the scoop 204. If the mouth 205 is placed flush to the vehicle
bumper 104, a turbulent air flow pattern caused by the surrounding
vehicle surfaces may be introduced. This may produce an inferior
quality air stream 201 into the mouth 205. Due to the variety of
vehicle configurations currently available, the optimum location of
the mouth 205 relative to the vehicle 100 will vary with each
vehicle model.
[0047] Referring now to FIG. 2, the mouth 205 may be flared such
that it has a mouth diameter 212 which tapers to a duct diameter
218. For reasons discussed in detail below, the narrowing of the
duct 202 in this manner may further optimize air flow through the
duct.
[0048] The air duct 202 is supported by a series of supports 203
connected to a chassis of the vehicle as best shown in FIG. 1. In
the first embodiment, three supports are used: a forward (or
bumper) bracket 203a, an intermediate bracket 203b near the elbow,
and rear bracket 203c near the nozzle. All brackets 203 attach to
the vehicle frame. While three brackets are shown herein, those
skilled in the art will realize that other mounting configurations
and methods could be used and still fall within the scope of the
invention.
[0049] Still referring to FIG. 1, at the opposite end of the scoop
204 is the nozzle 206. In one embodiment, the nozzle 206 may be a
flexible plastic or rubber material. Such construction permits the
nozzle 206 to be placed close to the ground without severe damage
from occasional contact with ground obstructions (e.g., off road
hazards, curbs, etc.). Where the nozzle can be mounted clear of
road obstacles, the material used may be a more rigid material
including plastic or PVC (polyvinyl chloride) tubing.
[0050] Ideally, the nozzle can be optimally located proximal to the
wheel. However, Applicant perceives that certain vehicle
configurations (e.g., vehicles having larger wheels like trucks and
semis) may necessitate mounting the nozzle farther from the ground.
In this case, air and entrained sand dispersed from the nozzle is
more heavily influenced by external factors such as cross-winds. In
this case, various techniques may be used to improve sand delivery.
One technique is the inclusion of a nozzle aiming mechanism 210 as
shown diagrammatically in FIG. 1. The aiming mechanism may be a
servo that makes the necessary adjustments to the flexible nozzle
assembly 206 based on commands from the controller 400. The
controller 400 may manipulate the aiming mechanism 210 based on
various inputs including the speed of the vehicle. Those of skill
in the art will realize that other inputs (e.g., crosswind sensors)
could also be used to control the aiming mechanism. As an
alternative to the nozzle aiming mechanism 210, the nozzle 206 may
include an extension (not shown) that extends and retracts from the
nozzle 206 to better direct the sand to the area 106. Accordingly,
various modifications are possible to accommodate less than optimal
nozzle placement. However, many vehicles will permit adequate
nozzle placement and thus may not require aiming mechanisms and
extension devices.
[0051] Another issue concerning nozzle placement involves the air
flow patterns around the front underside of the vehicle 100.
Specifically, as the vehicle travels, air incident on the front of
the vehicle is directed outwardly from the vehicle centerline. This
flow produces an outward air flow pattern in the vicinity of the
front tire 102. Sand 304 dispersed from the nozzle may be
influenced by this air stream and thus directed to an area beyond
(i.e., outward of) the tire 102. To counteract this effect, the air
duct 202 may be angled such that the air scoop 204 is located
inboard (i.e., closer to the vehicle centerline) of the nozzle 206
such that the nozzle 206 is aimed downwardly and outwardly from a
position slightly inboard of the tire as shown in FIG. 4. Thus, the
nozzle 206 is better positioned to take advantage of this external
outward flow pattern.
[0052] To optimize the air flow through the duct 202, a venturi may
be formed therein. A venturi is typically constructed by providing
an intermediate section in the conduit having a cross section
smaller than either the entrance or the exit. In the embodiment
represented in FIG. 2, the duct narrows from the flared diameter
212 to the reduced diameter 218. The duct expands again at the
nozzle 206 to a nozzle diameter 222. Interior to the nozzle 206 is
an internal baffle tube 224 whereby an annular portion 225 is
defined therebetween. The baffle tube 224 includes a series of
openings which, in one embodiment, comprise orifices 226 that are
smaller than the grain size of the sand 304. The purpose of the
baffle tube is to let air within the duct expand outwardly into the
annular portion 225 while the sand 304 is retained within the
baffle tube 224. This configuration permits the air stream 201 to
expand while restricting the sand dispersion pattern. Thus,
scattering of the sand 304 is minimized. In the first embodiment,
the orifices 226 are drilled at an angle (as shown in FIG. 2) to
better prevent the exit of sand 304 therethrough. While the venturi
configuration herein described may improve performance, it is not
critical to the operation of the traction enhancing device. That
is, the device 200 could operate with a constant duct diameter.
[0053] Still referring to FIG. 2, a neck 219 joins the scoop 204 to
the elbow 208. While shown in the first embodiment as a single
tube, the neck 219 can also be subdivided into separate air
passageways or "flutes" (not shown) to assist in the reduction of
turbulent flow within the air duct 202.
[0054] In one embodiment, the nozzle 206 is elliptical in cross
section wherein it has a larger fore-and-aft opening (the major
axis of the ellipse) than side-to-side opening (the minor axis of
the ellipse). As clearly shown in FIG. 2, the nozzle 206 may also
terminate parallel to the ground plane to form an exit having a
trailing edge 228 and a leading edge 230. This geometry provides
focused sand delivery and reduces sand scatter lateral to the
tire.
[0055] FIGS. 5 and 6 illustrate another embodiment of the nozzle
206. In this embodiment, the nozzle tube expands linearly to the
nozzle diameter 222 while the baffle tube 224 converges to a
smaller diameter 229. The narrowing baffle tube directs the
traction enhancing material to the predetermined location. The
baffle tube again includes orifices to permit the expansion of air
into the annular area 225. However, this particular embodiment
utilizes a series of slots 227 cut longitudinally in the baffle
tube 224 instead of the holes 226. The slot size can be optimized
to control the volume of air expanding from the baffle tube 224.
Like the orifices 226, the slots 227 are sized to permit passage of
air but prevent the passage of sand 304 therethrough. The slots 227
may be "V"-shaped as shown in FIG. 6 wherein the slot is wider on
the baffle tube outer diameter than on the inner diameter.
Alternatively, the slot walls may be parallel.
[0056] The nozzle 206 may form a separate "boot" that secures to
the air duct 202 or it may be formed integrally with the duct. It
may be made of a flexible or-semi-flexible material so that it is
better able to withstand contact with road obstacles.
[0057] Now referring to FIGS. 1 and 2, the elbow 208 will be
described. The primary purpose of the elbow is to provide a smooth
transition from the air scoop 204 to the nozzle 206. That is, it
diverts the air stream 201 from its predominantly fore-and-aft
direction to the downward and outward direction of the nozzle 206.
While only one elbow is shown, multiple elbows may receive air from
one scoop 204. The angle and radius of the elbow 208 are dependent
on the particular vehicle.
[0058] From the foregoing discussion, the optimal air duct 202 is
highly vehicle dependent. Accordingly, the embodiments described
herein are considered to be illustrative only.
Hopper
[0059] Referring once again to FIG. 2, the hopper assembly 300 may
be located generally above the air duct 202. Alternatively, the
hopper 300 may be remotely mounted. The purpose of the hopper 300
is to hold a sufficient quantity of material 304 to permit adequate
operation of the traction device 200. The hopper 300 includes a
removable hopper cover 306. The cover 306 permits selective filling
of the hopper while excluding foreign matter when the cover is
installed. It may include ventilation passages 308 to allow for the
escape of any moisture trapped within hopper 300. The hopper 300
may also include a screen (not shown) located at the top of the
hopper to exclude granular material too large for optimum
operation. A level sensor (not shown) may transmit volumetric
information to a dashboard panel 500 having an indicator 502 as
shown in FIG. 12.
[0060] The lower portion of the hopper forms an outlet channel 310
connected to the air duct 202 at the aperture 214. The aperture 214
is located above the elbow 208. The aperture 214 will be discussed
in more detail below. A heat trace 312 may encompass a bottom
portion of the hopper 300 and the channel 310 to prevent freezing
within the channel. The heat trace 312 may extend around portions
of the air duct 202 as well. In the first embodiment, the heat
trace 312 is a simple electrically resistive device.
Valve Assembly
[0061] The valve assembly 302 is shown in FIGS. 2, 3, 7, 8, and 9.
The primary function of the valve assembly is to selectively open
and close the aperture 214 in response to inputs from the
controller 400.
[0062] A valve plate 320 is shown in a closed position in FIG. 2.
In addition to the closed position shown, the valve plate 320 can
assume a fully open position or any intermediate, partially opened
position. In the closed position, the valve plate 320 interrupts
the flow of sand 304. In the open position, the sand 304
accelerates by gravity through the aperture 214 into the air duct
202 where it becomes entrained in the air stream 201. The amount of
sand 304 that is released into the air stream 201 can be limited by
positioning the valve plate 320 at an intermediate, partially open
position.
[0063] For optimum operation of the device 200, the valve plate 320
must be able to move freely. Accordingly, binding and interference
due to adjacent structure, sand, water, or contaminants must be
minimized. The first embodiment includes various features to
minimize binding and prevent contaminants from interfering with the
movement of the valve plate. However, other features may also be
incorporated and still fall within the scope of the invention.
Thus, the following description of the valve plate 320 and its
related components is considered to be illustrative only.
[0064] From FIG. 3, the surface of the valve plate 320 that
contacts the sand 304 is generally arc-shaped as viewed from the
front. This shape places the sand in close proximity to the air
stream within the duct 202. Referring now to FIGS. 2 and 7, the
plate 320 also forms a radius (when viewed from the side) that is
substantially congruent to the radius of the elbow 208 (see FIG.
2). This permits the valve plate to move freely between its opened
and closed positions without interference from the elbow 208. The
particular curved construction of the plate 320 furthermore places
the sand 304 near to the duct 202, thus minimizing any time delay
in introducing the sand 304 into the air stream 201. To further
improve time response, the valve plate 320 is constructed of a
relatively thin material and is positioned on the inside of the
duct 202 as near to the air stream 201 as possible.
[0065] Referring now to FIG. 8, the valve plate 320 tapers from a
wide forward edge 320a to a narrow trailing edge 320b, forming a
wedge shape when viewed from above. From FIG. 7, the trailing edge
of the valve plate 320 defines a sharp edge 321. These features, as
explained below, also minimize friction and drag on the valve plate
320 as it opens and closes.
[0066] Referring once again to FIGS. 2 and 3, the valve plate 320
further comprises a pair of arms 322 connected to a pivot axle 324.
The axle 324 is located generally below and transverse to the air
duct 202. However, other axle locations can be used without
departing from the scope of the invention. The pivot axle 324
defines the pivot axis for the valve plate 320 and defines the
center of the arc forming the top of the valve plate 320.
Accordingly, the axle 324 is positioned to permit unobstructed
movement of the valve plate 320 between its fully closed and fully
opened positions. Conventional bushings or bearings may be used
with the pivot axle 324 to permit smooth operation.
[0067] A solenoid 326, best viewed in FIG. 2, is pivotally
connected to the arms 322 at a pivot joint 328. The opposite end of
the solenoid 326 is connected to a fixed support (not shown). As
the solenoid extends and retracts, it pivots the arms 322, and thus
the valve plate 320 between the closed and opened positions
respectively. The solenoid 326 is biased to its extended position
by an internal spring such that the valve plate 320 is normally
closed. The movement of the solenoid 326 relative to the valve
plate position is not critical and thus other configurations (e.g.,
solenoid extends to open) can be utilized and still fall within the
scope of the invention. Additionally, other actuating devices
(e.g., servos, pneumatic cylinders, stepper motors, rack &
pinion mechanisms, etc.) are also contemplated. An enclosure 330
surrounds the axle 324, solenoid 326 and related components. The
enclosure may form a watertight seal around the solenoid, axle, and
a portion of the duct to exclude moisture and foreign matter from
contacting the valve assembly 302. In the first embodiment, the
enclosure 330 may support the axle 324.
[0068] Referring now to FIGS. 7-9, a bristled brush 332 extends
around the entire periphery of the aperture 214. The brush 332 acts
as a sand retaining member or barrier to prevent sand from flowing
from the hopper when the valve plate is closed. In the first
embodiment, the brush does not actually contact the plate 320 but
is positioned such that a slight clearance gap 336 exists (see FIG.
9). In one embodiment, the gap 336 is approximately {fraction
(1/32)}"-{fraction (1/16)}". While some sand can escape, the gap is
minimal so that sand becomes trapped and fills the gap. Thus, the
brush 332 contains the sand when the valve plate 320 is closed. In
one embodiment, the brush 332 may be mounted to an interior portion
of the channel 310 of the hopper 300.
[0069] While the brush 332 keeps the sand contained, it does not
seal the aperture 214 from the effects of weather. Since the sand
304 in the hopper 300 must be kept dry in order to properly
disperse, a water-tight gasket 334 as shown in FIGS. 7-9 extends
peripherally around the aperture 214 outside of the brush 332. The
gasket may be a single or multi-piece assembly but should provide a
relatively water-tight seal. The gasket 334 prevents moisture from
entering the hopper 300 either from the wheel well or from the duct
mouth 205. In the first embodiment, the gasket 334 seals along the
sides and back edge of the valve plate and then extends beneath the
front of the plate as shown in FIG. 7 to seal against a seal lip
318 integral to the plate 320.
[0070] Having described the components of the valve assembly 302,
its operation will now be discussed. Referring to FIG. 7, the valve
plate 320 is shown in its normally closed position. In this
position, the trailing edge 321 and the seal lip 318 are sealed
against the rear and front portions of the gasket 334 respectively.
Referring to FIG. 8, the tapered sides of the valve plate are also
sealed against the gasket 334. Accordingly, a water-tight seal is
formed around the entire aperture 214. The brush 332 extends around
a perimeter of the aperture 214 as shown in FIG. 8 and retains the
sand therein.
[0071] When the solenoid 326 retracts, the valve plate 320 opens.
As the plate opens, binding caused by the sand 304 is minimized due
to the clearance between the plate 320 and any surrounding
structure (e.g., the plate 320 does not contact the aperture 214,
brushes 332, or other surrounding structure with the exception of
the gasket 334). This clearance is maintained throughout the valve
plates's travel since the center of curvature of the top of the
valve plate 320 is coaxial with the axle 324 (see FIG. 7).
Accordingly, frictional binding is minimized. Furthermore, friction
between the gasket 334 and the valve plate 320 is reduced by the
wedge-shape of the plate 320 (i.e., as the plate opens, there is an
immediate separation between the plate 320 and the gasket 334) and
the immediate separation of the lip 318 and the edge 321 from the
gasket 334. Advantageously, the frictional forces acting upon the
plate are minimized.
[0072] The embodiments described above are intended to be
illustrative only. Other embodiments of the present invention could
be made which lack some or all of these low friction
characteristics without departing from the scope of the
invention.
[0073] When the plate closes, the sharp edge 321 permits the plate
to move through the falling sand 304 with relative ease. Once the
plate edge 321 engages the rear portion of the brush 332, the flow
of sand 304 is stopped. Yet the brush 334, as previously explained,
will permit the plate to move freely to its fully closed position.
Furthermore, the wedge-like shape of the plate results in
negligible gasket friction. That is, the plate 320 has little or no
contact with the gasket 334 until the plate has reached its fully
closed position.
[0074] Accordingly, the valve assembly 302 of the first embodiment
provides an efficient, water-tight seal for the aperture 314
without inducing significant frictional forces to the valve plate
320.
System Controller
[0075] Referring now to FIGS. 10-11, the system controller 400 is
shown in diagrammatic form. Referring first to FIG. 11, the
controller has a microprocessor 401 that receives inputs or signals
from several remote sensors, processes these signals and directs
the opening and closing of the valve assembly 302 as will be
described. The controller 400 may also have a memory device
405.
[0076] While described herein with reference to specific sensors,
those of skill in the art will realize that other sensing units may
also be included. For example, temperature sensors may be included
to determine if freezing conditions exist. With reference to the
exemplary embodiments described below, the actual sensors are known
in the art and are not discussed in detail herein. However,
reference is made to the sensor inputs and the controller responses
or outputs thereto.
[0077] The vehicle 100 may include one or more steering wheel
position sensors 474. These sensors inform the controller 400 of
the driver's steering inputs. As explained below, steering wheel
position is used in conjunction with other sensor readings to
determine if the vehicle 100 is responsive to turning inputs., One
or more wheel speed sensors 476 may be used to determine the speed
at which the tires/wheels are spinning. The wheel speed sensor may
be incorporated into the anti-lock braking system of the
vehicle.
[0078] X and Y accelerometers 478, 480 inform the controller 400 of
vehicle dynamic response to various operator commands. The X
accelerometer 478 measures acceleration along the fore-and-aft axis
of the vehicle 100. The Y accelerometer 480 measures acceleration
along an axis transverse to the vehicle. As those skilled in the
art will realize, accelerometers can detect both positive and
negative changes in acceleration. The X accelerometer signal may be
used by the controller to calculate the actual vehicle or ground
speed (true speed) by comparison of the signal over time. Other
techniques may also be used to measure ground speed. For example, a
radar unit may be incorporated onto the vehicle 100.
[0079] One or more position sensors 482 is also incorporated into
the valve assembly 302 to inform the controller 400 of the actual
valve opening. A first control output 484 controls the valve
position. Optionally, the controller may include a second control
output 486 to control the nozzle aiming mechanism 210. A nozzle
position sensor 488 may be included to inform the controller 400 of
the nozzle position. In one embodiment, the controller triggers a
visual and/or audio warning 504 (see FIG. 12) on the indicator
panel 500 that the valve assembly has opened. By receiving
notification that the device 200 has activated, the driver is made
aware of slippery road conditions that may have been otherwise
unknown.
[0080] Referring specifically to FIG. 10, one or more of these
signals are continually evaluated by the system controller 400.
When design thresholds are crossed, the controller commands the
normally closed valve assembly 302 open by energizing the solenoid
326 to move the valve plate 320. As previously described, the valve
plate can be opened in varying amounts corresponding to the
controller command. The plate remains at least partially open until
the controller senses traction has been restored.
[0081] In operation, the controller constantly monitors the wheel
speed sensors at 402 in FIG. 10. A predetermined threshold speed is
programmed into the controller 400. As long as the ground speed
remains below that threshold at 403, the traction device 200 will
not activate. In one embodiment, the threshold speed is 5 mph.
[0082] If the vehicle is traveling in excess of the threshold
speed, the controller 400 monitors the wheel speed sensors to
determine if one or more wheels is stopped at 404. If a wheel is
stopped, the controller reads the X accelerometer at 406 to
determine if the vehicle is decelerating properly. If the
controller determines the vehicle is decelerating at 408, it
returns to 402. If the controller determines otherwise, the
controller activates the driver warning 504 (see FIG. 12) at 409
and activates the valve assembly for the particular wheel at 410.
The valve is opened in proportion to the last known ground speed
(i.e., the wheel speed known right before the wheel stopped or the
anti-lock brake system engaged). At this point, the position of the
sand valve is read at 411 by the controller to determine if the
last known ground speed corresponds to the valve position at 412.
The valve plate 320 can be adjustably positioned between its opened
and closed position and thus may be calibrated to maintain a
certain opening at a certain speed. Once the controller determines
that the last known ground speed and the valve position correspond,
it reads the X accelerometer at 414 and calculates the actual
ground speed from the accelerometer signal at 416. With the actual
ground speed determined, the controller adjusts the valve assembly
302 to correspond to the calculated speed at 418. The controller
will continue with this process of reading the X accelerometer,
calculating the ground speed and adjusting the valve assembly until
it determines that the ground speed matches the wheel speed at 420.
A match indicates that traction has been regained and the
controller halts the dashboard alarm signal 504 at 422, closes the
sand valve at 424, and returns to 402.
[0083] The anti-lock brake system of the vehicle allows the gradual
rotation of the wheels. This gradual rotation "pins" the traction
enhancing material 304 under the tire, thus raising the coefficient
of friction to reduce the vehicle stopping distance.
[0084] The opening of the valve assembly 302 can be proportional as
described herein. Alternatively, the opening of the valve may be a
fluttering event with a longer elapsed open time of the valve for
higher ground speeds and less open time/more closed time as the
vehicle slows. With response time being critical, an alternative
design may utilize a solenoid to open the valve while the servo may
be used to gradually close the valve as the vehicle slows.
[0085] The identical technique is applied to each wheel having a
traction device 200 installed. The controller is capable of
simultaneously monitoring wheel speeds and valve positions for a
plurality of devices. Accordingly, the device 200 can function on
one or more wheels simultaneously.
[0086] Another condition frequently encountered on slippery
roadways is what is commonly referred to as a "spin out." Here, the
drive wheels encounter slippery road conditions and begin to spin
excessively. In this situation, the controller monitors wheel speed
as it did at 402. However, when the controller queries whether the
wheel is stopped at 404, the wheel speed sensor indicates the wheel
is spinning. The controller then determines whether the wheel is
spinning beyond a threshold level at 426. If the controller finds
that the wheel is spinning beyond the threshold level, it reads the
X accelerometer at 428 and compares the reading to the wheel speed
at 430. If the values do not match, the controller activates the
system and proceeds to 409 where it continues as described above.
If the wheel speed is found to correspond to the X accelerometer
reading, the system returns to 402.
[0087] Yet another condition addressed by the present invention
involves a turning sequence without braking. That is, the vehicle
driver turns to the right, for example, on a slippery road but the
vehicle doesn't respond. Like the spin out described above, the
controller queries whether the wheel(s) is spinning beyond the
threshold value at 426. However, unlike a spin out, the controller
finds that the wheel(s) is below threshold and proceeds to read the
Y accelerometer at 432 and the steering wheel position sensors at
434. If the controller 400 determines that the Y accelerometer
reading corresponds to the steering wheel position at 435, i.e., it
senses that the vehicle is actually moving in the direction it is
being turned, it returns to 402. However, if the two signals do not
correspond, the controller activates the dashboard indicator 504
(see FIG. 12) at 436. The controller then proceeds to read the X
accelerometer at 438, open the valve assembly 302 at 440, and read
the valve assembly position at 442. The controller than compares
the valve assembly position to the last known ground speed at 444.
The valve assembly 302 is adjusted until it corresponds to the last
known ground speed at 446. The controller then proceeds to read the
Y accelerometer at 448 and the steering wheel position sensors at
450 and compare the two readings at 452. If a match is not found,
the controller returns to 438 and executes the loop again. If a
match is determined, the controller turns the dashboard alarm off
at 454, closes the valve assembly at 456, and returns to 402.
[0088] The controller may also monitor the volume of traction
enhancing material 304 in the hopper 300. The level sensor is read
at 458 and, if found to be below a predetermined threshold level at
460, the controller provides an indication 502 (see FIG. 12) to the
driver via a visual or audible cue at 462. To accommodate larger
vehicles or larger volumes of traction enhancing material, the
system may incorporate a remote hopper (not shown). The remote
hopper would monitor the level in the hopper 300 and deliver an
amount of traction enhancing material when the level fell below the
threshold level.
[0089] To ensure that the system is operating correctly, a self
diagnostic may be performed each time power is provided (i.e., each
time the vehicle is started). The diagnostic can, for example,
verify that the controller is receiving the various control inputs
and that the internal controller electronics are functioning
properly. In the event of a detected fault, the diagnostic can
inform the driver with an audible or visual warning.
[0090] Other embodiments are also possible within the scope of the
invention. For example, FIG. 13 shows an auxiliary apparatus 600
that may be employed to improve reaction times and also improve
traction during hydroplaning (when tires "ride-over" a body of
water). The apparatus 600 may be used either independently or in
conjunction with the traction device 200. The auxiliary apparatus
600 utilizes a discharge unit 602 having a compressed gas source to
accelerate a projectile 608. In the embodiment shown in FIG. 13,
the discharge unit 602 is a modified version of the product
"Shocker Sport S/F" manufactured by Smart Parts, Inc.
[0091] Still referring to FIG. 13, the discharge unit 602 is
mounted within the wheel well by a series of brackets 603. The unit
602 is powered by compressed gas such as air, CO.sub.2, or
nitrogen. It is generally located in front of one or both front
tires 102 of the automobile 100 and has a barrel 604 aimed a
shallow angle toward the area 106. The discharge unit is modified
to be controlled by the system controller 400. That is, the
discharge unit 602 will discharge a pellet or projectile 608 on
command from the controller 400. In may also include a modified
barrel 604 to accommodate a larger projectile 608 as further
described below.
[0092] The discharge unit 602 is preferably protected from
contamination, especially water. To prevent entry of water into the
barrel 604, the barrel may have a series of flexible tabs 606 as
shown in FIG. 14. The tabs deflect to release the exiting
projectile 608 but close to prevent entry of contaminants.
[0093] Referring to FIG. 15, the projectile 608 may comprise a
spherical shell 609 having a granular substance 610 encased
therein. The substance 610 may be sand, crushed rock, salt, crushed
glass, or a combination thereof. In one embodiment, the shell 609
is formed from a soft gelatin material molded around the granular
substance 610. After the granular substance 610 is encased within
the gelatin shell 609, the shell is dried to produce a hard,
brittle projectile that will fracture on impact with the ground.
Upon fracture, the granular substance within is distributed to the
road surface. The shell may be biodegradable as well, eliminating
environmental waste concerns.
[0094] In addition to the shell-encased granular projectile 608,
the projectile may also be a glass sphere that is modified to
fracture on impact. This modification may be made by scoring,
crystallizing or other processing (e.g., heating followed by rapid
cooling), or modifications to the manufacturing method wherein
fracture planes are produced within the projectile 608. While
described as a sphere, projectiles of other shapes may also be
used.
[0095] In operation, the discharge unit 600 of FIG. 13 would fire
the projectile 608 in response to a loss of traction. Since the
unit 600 relies upon an energy source (compressed gas) rather than
gravitational forces, it is able to deliver the projectile to the
area 106 very quickly. When used in conjunction with the device
200, the apparatus 600 would operate for approximately the first
0.5 seconds. At that point, the device 200 can assume the delivery
of traction enhancing material 304 and the apparatus 600 may be
deactivated.
[0096] The apparatus 600 may also be of benefit when the vehicle is
hydroplaning. Because of the projectile speed, it can penetrate the
water surface and reach the area 106. On impact (or under the force
of the wheel), the sphere would fracture and thus distribute its
traction enhancing substance.
[0097] Other modifications are also possible within the scope of
the invention. For instance, in recent years, state transportation
departments have investigated how better to determine what roadways
need sanding or salting. To this end, the controller 400 may
communicate with a cellular phone 470 and a global positioning
system (GPS) 472 as shown in FIG. 11. Whenever the device 200 is
activated, the controller 400 can notify a bay station of the
location and time of activation using the GPS 472 and cellular
phone 470. Other parameters (e.g., vehicle identification) could
also be transmitted. After processing the information, the bay
station may relay this information to mobile sand trucks. Thus, the
transportation department is better able to identify and treat poor
road conditions that would otherwise remain unknown.
[0098] Another benefit of the present invention is its ability to
monitor the brake system. When the front wheel speed sensors
determine that the front wheels are approaching lock-up, the
controller can check the rear wheel speed sensors to determine if
the same braking condition exists. If not, the controller can
provide an indication to the driver that the fade between the front
and rear brakes may need adjustment.
[0099] Yet another benefit of the present invention involves
accident reconstruction. By providing the controller with
sufficient memory 405 (see FIG. 11) to store the X and/or Y
accelerometer signals for a period of time, the system may aid
officials in accident investigation. In particular, by retrieving
the accelerometer data from the controller, an investigator may be
better able to determine the sequence of events leading up to an
accident. The controller would only need to retain the information
for a short duration at which time the stored information could be
overwritten with new data. Other data including the steering wheel
position signal could similarly be stored.
[0100] The traction device of the present invention can also be
used with other vehicles besides automobiles. For example,
emergency vehicles, utility vehicles and even railroad vehicles may
incorporate the present design with minor modifications. In
addition, it may be incorporated into aircraft landing gear.
Furthermore, the control system 400 could be optimized for traction
during acceleration as well as stopping.
[0101] Accordingly, the present invention provides an effective
traction device that can be used on a variety of vehicles. By
taking advantage of the vehicle anti-lock brake system, the present
invention may provide improved traction with minimal dispersion of
sand. Additionally, the present invention takes advantage of air
incident on the vehicle rather than a separate power source to
disperse the traction enhancing material. Furthermore, the system
is fully automatic and requires no driver input in order to
operate.
[0102] Preferred embodiments of the present invention are described
above. Those skilled in the art will recognize that many
embodiments are possible within the scope of the invention.
Variations, modifications, and combinations of the various parts
and assemblies can certainly be made and still fall within the
scope of the invention. For example, an over-ride switch that
allows the operator to activate the valve on demand may be
provided. Thus, the invention is limited only by the appended
claims, and equivalents thereto.
* * * * *