U.S. patent application number 10/004702 was filed with the patent office on 2003-06-05 for remote-controlled, work-capable miniature vehicle.
Invention is credited to Gordon, Andrew W..
Application Number | 20030104756 10/004702 |
Document ID | / |
Family ID | 21712099 |
Filed Date | 2003-06-05 |
United States Patent
Application |
20030104756 |
Kind Code |
A1 |
Gordon, Andrew W. |
June 5, 2003 |
Remote-controlled, work-capable miniature vehicle
Abstract
A work-capable, miniature vehicle includes a small-scale
hydraulic system, a propulsion system, and a means for remote
control. The propulsion system includes a plurality of metal
tracks, which are individually controlled. The vehicle is adaptable
for performing work in hazardous areas. The vehicle comprises a
completed vehicle and a kit including the vehicle components.
Inventors: |
Gordon, Andrew W.; (Boca
Raton, FL) |
Correspondence
Address: |
J. Michael Boggs
Kilpatrick Stockton LLP
1001 West Fourth Street
Winston-Salem
NC
27101-2400
US
|
Family ID: |
21712099 |
Appl. No.: |
10/004702 |
Filed: |
December 4, 2001 |
Current U.S.
Class: |
446/154 |
Current CPC
Class: |
A63H 17/045 20130101;
A63H 30/04 20130101; A63H 29/10 20130101 |
Class at
Publication: |
446/154 |
International
Class: |
A63H 023/04 |
Claims
What is claimed is:
1. A miniature vehicle comprising: a frame; a propulsion system
mounted on said frame; a hydraulic system mounted on said frame; a
first actuator functionally connected to said propulsion system;
and a second actuator functionally connected to said hydraulic
system.
2. The miniature vehicle of claim 1, wherein said propulsion system
and said hydraulic system operate to perform work.
3. The miniature vehicle of claim 1, further comprising a
remote-control system functionally attached to said first actuator
and said second actuator.
4. The miniature vehicle of claim 3, wherein said remote-control
system comprises a radio-control system
5. The miniature vehicle of claim 1, wherein said miniature vehicle
comprises a scale-size version of a full-size vehicle.
6. The miniature vehicle of claim 1, wherein said propulsion system
comprises a plurality of metal tracks.
7. The miniature vehicle of 6, wherein said propulsion system
further comprises a discrete control mechanism for each of said
plurality of metal tracks.
8. The miniature vehicle of claim 6, wherein said propulsion system
further comprises: a power source; a motor functionally connected
to said power source, wherein said motor comprises an output shaft;
a first gear coaxially attached to said output shaft; a second gear
engaged with said first gear; a drive shaft coaxially attached to
said second gear; and a third gear coaxially attached to said drive
shaft, wherein at least one of said plurality of metal tracks
engaged with said third gear.
9. The miniature vehicle of claim 8, wherein said power source
comprises a gel-cell battery.
10. The miniature vehicle of claim 8, wherein said motor comprises
an electric motor.
11. The miniature vehicle of claim 8, wherein said propulsion
system further comprises a plurality of rollers attached to said
frame and engaged with each of said plurality of metal tracks.
12. The miniature vehicle of claim 6, wherein each of said
plurality of metal tracks further comprises a plurality of metal
links, each of said plurality of metal links having an inner
surface, wherein a pair of spaced apart connectors project from the
inner surface, and wherein the pair of spaced apart connectors of
each of said plurality of metal links is pivotally attached to the
pair of spaced apart connectors of an adjacent metal link so as to
form a continuous loop.
13. The miniature vehicle of claim 1, further comprising a body
mounted on said frame.
14. The miniature vehicle of claim 13, wherein said body comprises
a bulldozer body.
15. The miniature vehicle of claim 13, wherein said body comprises
a truck body.
16. The miniature vehicle of claim 13, wherein said body comprises
a crane body.
17. The miniature vehicle of claim 13, wherein said body comprises
a tank body.
18. The miniature vehicle of claim 1, further comprising a video
camera mounted on said frame.
19. The miniature vehicle of claim 1, further comprising a sensor
mounted on said frame.
20. The miniature vehicle of claim 1, further comprising a sample
gatherer mounted on said frame.
21. The miniature vehicle of claim 1, wherein said hydraulic system
comprises: a master cylinder having an input shaft; a slave
cylinder having an output shaft; and a hydraulic line in fluid
communication between said master cylinder and said slave
cylinder.
22. The miniature vehicle of claim 1, wherein said first actuator
comprises: a power source; and an electronic speed control
electrically connected to said power source.
23. The miniature vehicle of claim 1, wherein said second actuator
comprises: a power source; a motor operably connected to said power
source; an output shaft extending from said motor; a pinion gear
coaxially attached to said output shaft; and a rack transversely
engaged with said pinion gear and rigidly attached to said
hydraulic system.
24. The miniature vehicle of claim 23, further comprising: a switch
functionally connected between said power source and said motor;
and a servo functionally attached to said switch.
25. The miniature vehicle of claim 24, further comprising a
remote-control system functionally attached to said servo.
26. The miniature vehicle of claim 1, further comprising a
bulldozer blade assembly mounted functionally on said frame.
27. The miniature vehicle of claim 26, wherein said bulldozer blade
assembly comprises a bulldozer blade and a bulldozer blade arm,
wherein said bulldozer blade arm is pivotally connected to said
frame, functionally connected to said hydraulic system, and rigidly
connected to said bulldozer blade.
28. The miniature vehicle of claim 1, further comprising a ripper
assembly.
29. The miniature vehicle of claim 28, wherein said ripper assembly
comprises: a parallelogram ripper arm having a first member, a
second member, a third member, and a fourth member, wherein said
first member is pivotally attached to a first end of said third
member and pivotally attached to a first end of said fourth member,
said second member is pivotally attached to a second end of said
third member and pivotally attached to a second end of said fourth
member, and said first member is rigidly attached to said frame;
and a multi-shank ripper rigidly connected to said second member
and functionally connected to said hydraulic system.
30. A miniature vehicle comprising: a frame; a propulsion system
mounted on said frame; a hydraulic system mounted on said frame; a
first actuator functionally connected to said propulsion system; a
second actuator functionally connected to said hydraulic system;
and a remote-control system functionally attached to said first
actuator and said second actuator; wherein the miniature vehicle
further comprises a scale-size version of a full-size vehicle,
wherein said propulsion system further comprises a plurality of
metal tracks, each of said plurality of metal tracks having a
discrete control mechanism, and wherein said propulsion system and
said hydraulic system are operable to perform work.
31. A hydraulic system for a miniature vehicle comprising: a master
cylinder having an input shaft; a slave cylinder having an output
shaft; and a hydraulic line in fluid communication between said
master cylinder and said slave cylinder.
32. The hydraulic system of claim 31, further comprising an
actuator attached to said input shaft.
33. The hydraulic system of claim 32, wherein said actuator
comprises: a power source; a motor operably connected to said power
source; an output shaft extending from said motor; a pinion gear
coaxially attached to said output shaft; and a rack transversely
engaged with said pinion gear and rigidly attached to said input
shaft.
34. The hydraulic system of claim 33, further comprising: a switch
functionally connected between said power source and said motor;
and a servo functionally attached to said switch.
35. The hydraulic system of claim 34, further comprising a
remote-control system functionally attached to said servo.
36. The hydraulic system of claim 35, wherein said remote-control
system comprises a radio-control system.
37. The hydraulic system of claim 33, further comprising a
bulldozer blade assembly functionally connected to said output
shaft.
38. The hydraulic system of claim 33, further comprising a ripper
assembly to said output shaft.
39. A metal track for a miniature vehicle comprising a plurality of
metal links pivotally attached to one another so as to form a
continuous loop.
40. The miniature vehicle of claim 39, wherein each of said
plurality of metal tracks further comprises a plurality of metal
links, each of said plurality of metal links having an inner
surface, wherein a pair of spaced apart connectors project from the
inner surface, and wherein the pair of spaced apart connectors of
each of said plurality of metal links is pivotally attached to the
pair of spaced apart connectors of an adjacent metal link so as to
form a continuous loop.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of and priority to PCT
Application Serial No. PCT/US01/, for inventor Andrew W. Gordon,
filed by DirtBilt, Inc., on Oct. 26, 2001, which is incorporated by
reference herein in its entirety.
NOTICE OF COPYRIGHT PROTECTION
[0002] A portion of the disclosure of this patent document and its
figures contain material subject to copyright protection. The
copyright owner has no objection to the facsimile reproduction by
anyone of the patent document or the patent disclosure, but
otherwise reserves all copyrights whatsoever.
FIELD OF THE INVENTION
[0003] The present invention relates in general to small-scale
vehicles and in particular to remote-controlled, small-scale
vehicles.
BACKGROUND
[0004] A variety of small, remote-controlled vehicles are available
on the market. These vehicles are commonly radio-controlled "toy"
vehicles, such as cars or trucks, which are built primarily for
entertainment purposes. Such toy vehicles are not made to
accomplish work and, therefore, do not include robust propulsion
and accessory systems. In contrast, full-size machines designed to
perform work have very robust propulsion and accessory systems.
[0005] For example, a small, tracked vehicle conventionally
includes a small battery-powered motor driving a plastic or rubber
track or may even include a hidden drive wheel, relegating the
track to mere decoration. As a result, a small, tracked vehicle may
be able to push only very small items, weighing much less than the
vehicle itself. Also, the small vehicle may be able to traverse
only minimal obstacles and may operate for a short period of time
before requiring its batteries to be charged or replaced. Many
conventional toy vehicles are powered by limited-life power
sources. For example, a toy vehicle utilizing a nickel-cadmium
power supply may have an elapsed running time of only ten to
fifteen minutes.
[0006] In contrast, a larger tracked vehicle includes a powerful
electric or combustion engine driving a metal track. A larger
vehicle is capable of pushing very heavy objects and traversing
substantial barriers. With large fuel tanks and/or battery packs, a
larger vehicle is able to perform work for an extended period of
time.
[0007] Accessory systems on small vehicles are designed primarily
for form rather than function. For example, on a conventional toy
bulldozer, the blade assembly is raised and lowered using a servo,
battery-powered motor, and/or spring-driven mechanism. In contrast,
a large, scale-size bulldozer utilizes a hydraulic system to raise
and lower the blade.
[0008] Conventional small, remote-controlled vehicles appeal to
individuals purchasing a model for entertainment. However, serious
model enthusiasts, organizations wishing to use remote-controlled
vehicles in hazardous situations, and others desire small-scale
vehicles having more robust features and capabilities than
conventional toy vehicles. Thus it would be advantageous to provide
a small-scale, remote-controlled vehicle that is capable of
performing work.
SUMMARY
[0009] Embodiments of the present invention provide miniature
vehicles capable of performing work. One such embodiment of the
present invention comprises a miniature vehicle that is a
small-scale version of a full-size machine and that is
remote-controlled. The miniature vehicle includes a working
hydraulic system for manipulating attachments and a propulsion
system having individually controllable metal tracks. The miniature
vehicle is capable of performing work for recreational purposes,
and commercial and law enforcement-related purposes, such as the
work involved in dealing with hazardous materials or
surveillance.
[0010] In embodiments of the present invention, a miniature vehicle
comprises a frame, on which a propulsion system and a hydraulic
system are mounted. The miniature vehicle comprises a first
actuator to control the propulsion system and a second actuator to
control the hydraulic system. The propulsion system may include a
plurality of metal tracks, wherein each track comprises a plurality
of metal links attached pivotally to the two adjacent links to form
a continuous loop. The propulsion system includes a discrete
control mechanism for each track. For example, in an embodiment of
the present invention, a miniature bulldozer includes a separate
control mechanism for each track so that turning the bulldozer is
accomplished by varying the speed and/or direction of the
individual tracks. The propulsion system includes a power source,
such as a battery. In an embodiment of the present invention, a
gel-cell, twelve-volt battery provides the vehicle with the
advantage of a relatively long operating time. The propulsion
system also includes an electronic speed control linked to a
radio-control or other control system.
[0011] A hydraulic system in an embodiment of the present invention
is similar to a brake system in an automobile, comprising a master
cylinder in fluid communication with at least one slave cylinder
and forming a closed loop system. The hydraulic system includes a
rack-and-pinion mechanism, which is attached to an input shaft of
the master cylinder. Rotation of the pinion gear causes the rack to
move and causes inward movement of the input shaft in the master
cylinder. This inward movement forces hydraulic fluid through
hydraulic lines to a slave cylinder. The hydraulic pressure caused
by the fluid movement causes extension of an output shaft of the
slave cylinder.
[0012] The pinion gear is rotated by an electric motor, which is
connected to and activated by a toggle switch. The toggle switch
is, in turn, activated by a radio-controlled servo. In embodiments
of the present invention, a hydraulic system can utilize mineral
oil as the hydraulic fluid. Mineral oil provides the advantages of
being non-toxic and non-staining.
[0013] Embodiments of the present invention include a body, or
shell, for a miniature vehicle. A body attaches to the frame and
may be interchangeable with other bodies. For example, a bulldozer
body can be interchanged with a tank body. Examples of bodies in
other embodiments include a truck body or a crane body.
[0014] In an embodiment of the present invention, a miniature
bulldozer includes a bulldozer blade. The bulldozer blade is
connected to the hydraulic system so that the hydraulic system
raises and lowers the blade. The bulldozer may also include a
ripper arm. The ripper arm is also attached to the hydraulic system
so that it may be raised and lowered.
[0015] Embodiments of the present invention include a wireless
video camera, sensor, detector and/or sampling devices mounted
directly or indirectly to the vehicle frame. Embodiments for use in
a law enforcement or military capacity include weapons and
detectors, such as land mine detection and/or pre-detonation
devices.
[0016] An embodiment of the present invention provides advantages
over conventional small, remote-controlled toy vehicles. These
advantages include robust propulsion and hydraulic systems in a
miniature, remote-controlled, scale-size vehicle. Such features
provide advantages to the serious hobbyist, to organizations
wishing to use remote-controlled vehicles in hazardous situations,
and others.
[0017] One advantage of the present invention is that the robust
propulsion system resembles that of a full-size machine and allows
the vehicle to traverse terrain and obstacles beyond the
capabilities of a less robust, remote-control vehicle. Another
advantage is that a working hydraulic system closely reflects such
a system in a full-size machine and allows the small vehicle to
perform tasks that a toy vehicle cannot.
[0018] Embodiments of the present invention have the further
advantage of reducing the safety risks encountered by police
officers and military personnel in hazardous situations. For
example, an embodiment including a video camera performs
reconnaissance in a hazardous situation that would otherwise
require the presence of a person.
[0019] Further details and advantages of the present invention are
set forth below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] These and other features, aspects, and advantages of the
present invention are better understood when the following Detailed
Description is read with reference to the accompanying drawings,
wherein:
[0021] FIG. 1 is a side perspective view of an embodiment of the
present invention as a bulldozer.
[0022] FIG. 2 is a side, rear view of the drive components in an
embodiment of the present invention.
[0023] FIGS. 3A, 3B, 3C, and 3D illustrate components of a track
propulsion system in an embodiment of the present invention.
[0024] FIG. 4 is a top perspective view of a hydraulic system in an
embodiment of the present invention.
[0025] FIGS. 5A and 5B illustrate a ripper assembly in an
embodiment of the present invention.
[0026] FIGS. 6A and 6B illustrate various shells for attachment to
a frame in an embodiment of the present invention.
DETAILED DESCRIPTION
[0027] Embodiments of the present invention include a frame on
which is mounted a propulsion system, including metal tracks, a
hydraulic system, a power supply, and a control system. These
aspects provide robustness to a miniature vehicle, allowing the
vehicle to perform work. In an embodiment of the present invention,
the control system is a remote-control system, such as a
radio-control system, which provides an operator of the miniature
vehicle the ability to operate the vehicle in remote locations.
[0028] FIGS. 1-6 illustrate various aspects of embodiments of the
present invention as a small-scale version of a full-size vehicle,
which is capable of performing work. FIG. 1 illustrates an
embodiment of the present invention as a miniature bulldozer 120.
Embodiments of the present invention comprise a frame to which
other components may be mounted. The frame (not shown) comprises
aluminum and/or some other material suitable for mounting various
components of the machine.
[0029] A propulsion system is mounted on the frame of miniature
bulldozer 120. The propulsion system comprises a pair of metal
tracks 105a and 105b. A gear 107a drives track 105a. A series of
rollers 109a-d guide the bottom portion of track 105a. The
propulsion system further comprises a guide wheel 108 on which
track 105a is seated.
[0030] Bulldozer 120 includes an actuator (not shown) for
activating and controlling the propulsion system. For example, the
propulsion system actuator on bulldozer 120 may include a
remote-controlled electronic speed control. Alternatively, the
actuator includes a pre-programmed, computer-controlled propulsion
system actuator. The actuator controls tracks 105a and 105b
individually, allowing the bulldozer 120 to execute turns by
varying the speed and/or direction of tracks 105a and 105b.
[0031] Referring again to FIG. 1, bulldozer 120 also comprises a
bulldozer blade assembly 110, 111 and a ripper assembly 112, 113.
Blade 110 is rigidly connected to a blade arm 111, which is
pivotally connected to the frame of bulldozer 120. Ripper 112 is
similarly attached to the frame of bulldozer 120 via a
parallelogram ripper arm 113. Both the blade 110 and the ripper 112
are operated with a hydraulic system mounted on or to the
frame.
[0032] In the embodiment illustrated in FIG. 1, a hydraulic system
includes hydraulic slave cylinders 101a, 101b, and 103. Slave
cylinders 101a and 101b are in fluid communication with a first
master cylinder (not shown). Slave cylinder 103 is in fluid
communication with a second master cylinder (not shown). Slave
cylinders 101a and 101b are further attached to blade arm 111 and
operate to raise and lower blade 110. Slave cylinder 103 is
attached to ripper arm 113 and operates to raise and lower ripper
arm 113 and ripper 112.
[0033] In addition to a propulsion system actuator, bulldozer 120
also includes an actuator to separately control the hydraulic
systems attached to blade 110 and ripper 112, respectively. Similar
to the propulsion system actuator, the hydraulic system actuator
may include a remote-controlled system, such as a radio-controlled
servo system.
[0034] The bulldozer 120 in FIG. 1 is robust and capable of
performing work. For example, in experimentation, bulldozer 120 was
found to be capable of pushing a cinder block, weighing over
thirty-six pounds. Also, bulldozer 120 was found to be capable of
pulling a wagon carrying in excess of fifty-five pounds.
[0035] Propulsion System
[0036] As described briefly above, an embodiment of the present
invention comprises a propulsion system. The propulsion system
includes wheels and/or tracks. FIG. 2 illustrates a track
propulsion system in an embodiment of the present invention.
[0037] The track propulsion system shown in FIG. 2 comprises a pair
of tracks 105a and 105b. Each of the tracks 105a, 105b is driven by
a discrete control mechanism. Gears 107a and 107b drive tracks 105a
and 105b, respectively, and are connected to matching drive
systems. Gear 107a is attached coaxially to drive shaft 208. In the
embodiment shown in FIG. 2., gear 107a is attached at an outside
end of drive shaft 208. In other embodiments, the drive gear 107a
is attached at various positions along the length of drive shaft
208. Gear 202 is also attached coaxially to drive shaft 208 so that
when gear 202 rotates, drive shaft 208 rotates as well. Rotation of
drive shaft 208 causes rotation of gear 107a and a corresponding
movement of track 105a. Gears 107a and 202 may be of the same or
different sizes.
[0038] Gear 202 is engaged with gear 203. Gear 203 is coaxially
attached to an output shaft (not shown) from motor 201a. The
embodiment shown in FIG. 2 comprises a motor 201a. Motor 201a
drives a single track. Various other embodiments of the present
invention comprise a more than one motor, depending on the
wheel/track design and degree of control desired. Motor 201a
provides sufficient power to perform work. In one embodiment of the
present invention, the motor, such as motor 201a in FIG. 2, is a
twelve-volt motor, which provides an amount of torque sufficient to
allow the machine to push or pull heavy loads.
[0039] The machine shown in FIG. 2 also includes a speed control
205. The speed control 205 is attached to the motors 201a, b by
electrical control wires 204a, b, respectively. Speed control 205
may comprise an electronic speed control, providing proportional
and infinitely variable individual speed and directional control of
motors 201a, b. For example, an embodiment of the present invention
utilizes the Novak Super Rooster reversible digital speed control
to distribute power to the motors.
[0040] The speed control is attached to various other components.
For example, in an embodiment of the present invention, comprising
a radio-controlled machine, the speed control is attached to a
radio receiver. Attached to the radio receiver is an antenna that
receives signals from a transmitter. The transmitter includes a
right and a left joystick. When the right joystick is moved
vertically forward or backward from a neutral and/or centered
position, the joystick movement causes a corresponding movement in
the right track of the machine. If both joysticks are moved forward
or backward in unison, the machine moves forward or backward
respectively. If the left and right joystick are moved in different
directions or in differing amounts, the machine turns towards the
track which is moving more slowly. For example, if the right
joystick is pulled backward, causing the right track to reverse,
and the left joystick is pushed forward, causing the left track to
move forward, the machine turns to the right.
[0041] In other embodiments of the present invention, the speed
control includes mechanical controls, such as toggle switches. The
toggle switches are connected to miniature control devices in the
machine that are visible to a person observing the machine working.
The movement of the control devices provides animation in an
embodiment of the present invention.
[0042] In the embodiment shown in FIG. 2, gel-cell battery 207 is a
power source that provides energy to the speed control 205 and
motors 201a, b. The battery 207 is electrically connected to speed
control 205 via a wire 206. In the machine shown in FIG. 2, a
12-volt gel cell battery has an operating time of approximately 2
to 6 hours between charges, depending on operating conditions and
loads.
[0043] The track 105a shown in FIG. 2 comprises a plurality of
metal links. FIGS. 3A-D illustrate an embodiment of elements of
track 105a in separate views, the combination of elements of track
105a, and the interaction of elements of track 105a with drive and
suspension systems of the present invention.
[0044] FIG. 3A is a side view of a track link 301a. Track link 301a
comprises a pair of connectors, represented by connector 302a in
FIG. 3A. As shown in FIG. 3C, the connectors 302a, b are mounted
transversely to track link 301a and project beyond the surface of
track link 301a.
[0045] FIG. 3C provides a perspective view of the link from above a
surface of link 301a to which the connectors 302a, b are attached.
Connector 302a is parallel to connector 302b and each is shaped so
that the space between them is narrow at one end and wide at the
other end. The narrow and wide ends of connectors 302a, b are
complementary. The distance between the outside edges of the
connectors 302a, b at the narrow end is less than the distance
between the inside edges of each connector at the wide end, such
that the narrow end may be inserted into the wide end of an
adjacent link. The adjacent links are attached by various pivotal
means, such as pins and rods.
[0046] FIG. 3D illustrates track 105a, comprising a plurality of
links 301a-d so attached. As shown in FIG. 3D, once the links
301a-d have been pivotally attached, they functionally engage drive
gear 107a. Once the links 301a-d are engaged with gear 107a, then
when gear 107a rotates, track 105a moves, sliding along roller 109a
with which track 105a is also engaged.
[0047] The tracks illustrated in FIGS. 3A-D may comprise various
materials, including rubber, plastic, and/or metal. In a preferred
embodiment of the present invention, the tracks are metal, and the
metal is of sufficient hardness so as to resist galling. For
example, the tracks may comprise stainless steel and/or other steel
and steel composites. Alternatively, the links may comprise a
relatively hard or zinc-anodized aluminum.
[0048] In an embodiment of the present invention as a front-end
loader, the propulsion system comprises four wheels. Power is
supplied to one or more of the four wheels by an electric motor,
such as the motors shown in FIG. 2. Steering of a front-end loader
is accomplished through use of differential speed to wheels on
opposite sides of the machine and/or by the addition of a steering
mechanism to the front or rear of the machine.
[0049] In an embodiment of the present invention as a tank,
suspension elements are included in track 105a for greater realism
and functionality.
[0050] Hydraulic System
[0051] An embodiment of the present invention comprises a hydraulic
system for performing work. FIG. 4 illustrates the various
components of a hydraulic system in an embodiment of the present
invention. The hydraulic system shown in FIG. 4 operates the
bulldozer blade 110, as shown in FIG. 1.
[0052] The hydraulic system shown in FIG. 4 is similar to a braking
system in an automobile and comprises a master cylinder 409 as well
as a slave cylinder 101a. Such a system is known as a closed-loop
system. In this closed-loop system, a constant volume of fluid is
transferred back and forth between the master cylinder 409 and the
slave cylinder 101a during operation of the hydraulic system.
Mineral oil, which is non-toxic and non-staining, is advantageously
utilized as hydraulic fluid in embodiments of the present
invention.
[0053] Master cylinder 409 includes an input shaft 408. Movement of
input shaft 408 causes a corresponding movement of a piston within
master cylinder 409. Movement of the piston causes hydraulic fluid
to be pressurized within master cylinder 409 on the side towards
which the piston is moving. Master cylinder 409 is in fluid
communication with slave cylinder 101a. When the input shaft 408 is
moved inwardly in the master cylinder, fluid is forced out of the
opposite end of master cylinder 409 through a valve or fitting 410a
into hydraulic line 412a.
[0054] Slave cylinder 101a includes a fitting 410b at one end,
which is attached to hydraulic line 412a at an end opposite the
master cylinder 409. The pressure of the fluid exiting master
cylinder 409 causes the fluid to flow through hydraulic line 412a
and enter slave cylinder 101a through fitting 410b. This movement
of hydraulic fluid into slave cylinder 101a causes a piston (not
shown) inside slave cylinder 101a to move in the direction opposite
fitting 410b. Attached to the slave cylinder piston is an output
shaft 411. Movement of the piston causes a corresponding movement
of output shaft 411. Thus, when hydraulic fluid enters slave
cylinder 101a at one end of slave cylinder 101a, output shaft 411
moves outwardly from the opposite end of slave cylinder 101a.
Movement of the slave cylinder piston forces hydraulic fluid to
exit slave cylinder 101a at fitting 410d and enter hydraulic line
412b. The fluid then flows through hydraulic line 412b and enters
master cylinder 409 at fitting 410c.
[0055] Therefore, a control force exerted on input shaft 408 causes
a corresponding, opposite movement of output shaft 411. An inward
movement of input shaft 408 causes a corresponding outward movement
of output shaft 411. Likewise, outward movement of input shaft 408
causes inward movement of output shaft 411.
[0056] The output shaft 411 is functionally connected to a
bulldozer blade assembly, including blade 110 and blade arm 111.
Output shaft 411 is attached to blade arm 111, which is attached to
the vehicle frame. Blade arm 111 is also attached to blade 110. In
the embodiment shown in FIG. 4, an outward movement of output shaft
411 causes blade 110 to lower. An inward movement of output shaft
411 causes blade 110 to rise. It is known that hydraulic fluid does
not compress. Therefore, once the blade 110 is lowered, the blade
110 will not rise unless a force is applied to the blade 110 and/or
output shaft 411 that is greater than either the force that the
weight of the miniature bulldozer is applying downward on the blade
110 or the amount of force the hydraulic system is capable of
withstanding before failure.
[0057] For example, in the embodiment shown in FIG. 4, the
hydraulic lines 412a, b and the fittings 410a-d on the master
cylinder 409 and slave cylinder 101a are capable of providing
hydraulic pressure in excess of 150 pounds per square inch (PSI).
The force the machine is capable of exerting through the hydraulic
system is calculated using the formula,
Force=(1/(r.sub.piston.sup.2*.PI.))*Machine Weight, where
r.sub.piston is the radius of the piston in inches and Machine
Weight is the weight of the machine in pounds. In the embodiment
shown in FIG. 4, the radius of the piston is 0.3125 inches and the
machine weights 39 pounds. Applying this formula to the embodiment
shown in FIG. 4 ((1/(0.3125*3.1417)*39 pounds) shows that the
machine is capable of exerting a force of approximately 127
PSI.
[0058] In the embodiment shown in FIG. 4, the input shaft 408 of
master cylinder 409 is moved using a rack and pinion system. An end
of rack 404 is attached to input shaft 408. Along one side of rack
404 are teeth. The teeth in rack 404 are transversely engaged with
gear 402. To ensure that rack 404 remains engaged with gear 402,
rack 404 rolls along roller 401 on the side of rack 404 opposite
gear 402.
[0059] The gear 402 is coaxially attached to an output shaft of an
electric motor (not shown). When the electric motor operates, it
rotates gear 402. The electric motor is electrically connected to a
switch 407. The switch 407 is connected to and controlled by a
servo 406. Battery 207 is connected to and provides power for both
servo 406 and, via switch 407, the electric motor that operates
pinion gear 402. A limiter 403 is connected to the electric motor
to stop the motor when input shaft 411 reaches its limit of inward
or outward movement from master cylinder 409.
[0060] Embodiments of the present invention further comprise a
radio receiver connected to the hydraulic system for remote
operation of the hydraulic system. In various embodiments, the
hydraulic system powers various types of accessories, such as
ripper arm 112 shown in FIG. 1. Examples of these accessories
include a gun in the turret of a tank, a bucket on a front-end
loader, or forks on a fork lift.
[0061] An embodiment of the present invention comprising a
miniature bulldozer further includes a ripper 112. FIGS. 5A and 5b
illustrate the ripper 112 shown in FIG. 1. The ripper 112 shown in
FIG. 5A is an example of a multi-shank ripper, comprising dual
shanks. The ripper 112 is attached a to an end of the outer member
501 of parallelogram ripper arm 113.
[0062] In FIG. 5B ripper arm 113 comprises four members, which are
attached to form a parallelogram arm. Members opposite one another
remain in parallel throughout the arm's motion. Multi-shank ripper
112 is rigidly attached to member 501. Member 502 is attached to
the frame of the machine and remains in parallel with member 501.
Members 503 and 504 form the top and bottom of the ripper arm and
are attached to member 502 at one end and member 501 at the other.
Members 503 and 504 may be separated to provide stability to the
arm. In an embodiment of the present invention, members 503 and 504
are duplicated on an opposite side of members 501 and 502 to
provide further stability. Ripper 112 and/or ripper arm 113 is
attached to the hydraulic system to facilitate raising and lowering
of the ripper 112.
[0063] In embodiments of the present invention, the miniature
vehicle includes interchangeable shells or bodies. FIG. 6A
illustrates an embodiment of the present invention as a bulldozer.
To attach bulldozer body 610 to the frame of the vehicle,
predrilled holes 601 and 603 in bulldozer body 114 are aligned with
holes 602 and 604 in the frame. Fasteners, such as allen-head
screws, are then inserted through the holes to attach the body 610
to the frame.
[0064] FIG. 6B illustrates a tank body 605. Tank body 605 comprises
two holes 606 and 607 that align with holes 602 and 604
respectively. As such, one body can be easily removed from the
frame and a different body attached in its place. Other embodiments
include bodies of, for example, a crane, a truck, a forklift, a
front-end loader, and an armored personnel carrier.
[0065] Embodiments of the present invention include elements that
add aspects of a life-size vehicle to a miniature, scale-size
vehicle and provide useful functions for work activities. For
example, an embodiment may include a sound module and lighting
accessories. These features allow a miniature vehicle to light a
work area and to communicate with a dangerous person in a hazardous
environment.
[0066] An embodiment of the present invention includes a miniature
wireless video camera mounted on the frame. A video camera provides
a person operating the vehicle with a view that approximates the
view an operator of a full-scale vehicle has. A camera provides the
person operating the vehicle in a hazardous situation with a means
of viewing situations encountered by the machine without subjecting
the person operating the machine to the hazard.
[0067] An embodiment of the present invention further comprises
weapons, detectors, sensors, and sample gathering devices, which
enhance the work capabilities of the vehicle in hazardous
situations. For example, an embodiment comprises a device to
deliver tear gas and/or an infrared sensor capable of helping
police assess and intervene in a potentially dangerous situation.
Additionally, a vehicle designed to perform land mine detection and
removal comprises land mine detectors and/or pre-detonation
devices.
[0068] An embodiment of the present invention comprises a kit. In
one embodiment, the kit includes all of the materials necessary to
assemble a complete vehicle, such as a bulldozer. In another
embodiment, the kit includes a single sub-system of a vehicle. For
example, one kit includes a frame and a propulsion system. A second
kit includes a single hydraulic system. In order to assemble a
complete bulldozer, including a bulldozer blade 110 and ripper 112,
one frame and propulsion kit and two hydraulic system kits are
used.
[0069] Other kits according to the present invention include a
radio-control system. In an embodiment of the present invention as
a bulldozer, the kit includes a four-channel radio. The kit also
includes a electronic speed control to control each of the two
electric propulsion motors 201a, b and two servos to control each
of the two hydraulic systems for the bulldozer blade 110 and ripper
arm 112. In such an embodiment, forward and backward movements of a
control stick on the transmitter control the speed and direction of
movement of the corresponding track. Left and right movements of a
control stick cause operation of a hydraulic system.
[0070] The foregoing description of the preferred embodiments of
the invention has been presented only for the purpose of
illustration and description and is not intended to be exhaustive
or to limit the invention to the precise forms disclosed. Numerous
modifications and adaptations thereof will be apparent to those
skilled in the art without departing from the spirit and scope of
the present invention.
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