Note: Descriptions are shown in the official language in which they were submitted.
CA 02309128 2000-04-23
AUTONMATIC GLIDER FIFTH WHEEL ATTACHMENT
FIELD OF THE INVENTION
The present invention relates generally to toxvin; devices and, more
particularly, to an
adjustable fifth wheel hitch attachment for enhanced maneuverability in
limited or tight
operating areas.
BACKGROLND OF THE INVENTION
Fifth wheel hitches for towing a trailer behind a towinc, vehicle are well
known in the
art. Typically, fifth wheel hitches include a support frame for mounting the
hitch to the
towing vehicle. Usually, fifth wheel hitches are mounted within the bed of a
pick-up truck.
The support frame includes a pair of transverse rails that are bolted to the
bed and/or frame of
the truck, rail assemblies that are releasably mounted to the transverse rails
and upri~ht
assemblies mounted to the rail assemblies. A transverse cross bar typically
interconnects the
upright assemblies, thereby forming a head support for mounting a head
assemblv by means
of a trunnion arrangement allowing for pivotal fore and aft movement. The head
assembly
includes ajaw assembly operable by means of a control handle and is
specifically adapted to
releasablv enoaee and hold a kingpin of a towed vehicle.
Conventional fifth wheel trailer hitches typically limit the maneuverabilitv
of a
towing vehicle at low speeds and in close quarters. In particular, fifth wheel
hitches typically
center the kinapin of the towed vehicle substantiallv betveen the rear wheels
and over the
rear axle of the towing vehicle. When so mounted, very close clearance is
provided between
the towed vehicle and portions of the towing vehicle. Under normal towing
conditions, the
close clearance is sufficient to allow effective operation under speed on the
open road.
However, the close clearance may hinder maneuverability, especially in
situations requiring
CA 02309128 2000-04-23
tight cornering within limited space. such as, for example, the conditions
found at
campgounds and some trailer parks.
In order to address the maneuvering shortcomings of conventional fifth wheel
trailer
hitches, various attempts at adjustable fifth wheel hitches have been made. It
has been found
~ that by temporarily moving the hitch assembly rearward in the towing
vehicle, clearance
between the towing vehicle and the towed vehicle is increased, thereby
allowing for greater
maneuverability of the towed vehicle. In one adjustable fifth wheel hitch
design, the towed
vehicle must be detached from the fifth wheel hitch prior to any adjustment of
the fifth wheel
hitch. The detachment efforts are time consuming and require precise movement
of the
to towing vehicle. The adjustable hitches also typically require more than one
person to effect
the adjustment of the fifth wheel hitch. Another design utilizes low friction
shoes within
upright mounting members for movement on parallel guide rails. The uprights
are selectively
slideable along each guide rail. Each upright includes a hollow cavity for
receiving a dual
bar latch and a leaf spring for biasing the dual bar latch into a position to
lock the upriQhts
i~ aQainst slideable movement. However, the effective weight borne by the low
friction shoes
tends to cause binding of the shoes such that seizing mav occur. The high
friction between
movinQ parts prevents easy and smooth adjustment of the tifth -heel trailer
hitch. Moreover,
the latchina mechanism is hidden from view, thereby preventing an operator
from confirming
enaagement of the locking mechanism to lock the adjustable portion against
slideable
20 movement.
SUM-NIARY OF THE Ii IVENTIO\
The present invention is directed to a glider fifth wheel attachment assembly
for use
with fifth vvheel towing assemblies attached to motor vehicles. The glider
fifth wheel
'_~ attachment assembly includes a support frame including a pair of spaced
guide rails and a
~
CA 02309128 2000-04-23
pair ofupriaht assemblies attached to the vuide rails. Each upright assembly
includes a lower
sleeve portion for receivinc, a respective 2uide rail, an intermediate housing
portion vertically
above the sleeve portion, and an upper mounting portion vertically above the
housing portion.
A head assembly may be adjustably mounted between respective mounting portions
of the
upright assemblies. One roller is positioned within each housing, portion of
the upright
assemblies such that the roller contacts an upper surface of an upper guide
rail. The glider
fifth wheel attachment assemblv further includes a latching assembly for
releasablv locking
the glider fifth wheel attachment assemblv between a first and a second towing
position.
In a first embodiment, each housing portion includes two spaced rollers
contacting the
l0 upper surface of the respective szuide rails. In a more preferred
embodiment, the latching
assembly further includes a generally L-shaped bar, wherein a first end of the
bar extends
throuah aligned apertures in the housing portions. At least one latch pin is
mounted parallel
to and laterally spaced from the first end adjacent at least one of the
upright assemblies. The
latch pin is received in one of a pluralitv of apertures formed in the guide
rails, wherein the
plurality of apertures correspond to the respective first and second
positions. Moreover, the
latchin, mechanism is preferablv biased to a latched position in either the
first or second
position by means of a compression spring located along the first end of the
latchinc, bar. The
housing portions may further include at least one strap parallel to an axis of
rotation of the
rollers, and closely adjacent there:u.
In a second embodiment, fore and aft movement of the glider fifth wheel hitch
may be
automatically accomplished without requirina that the vehicle operator exit
the vehicle.
Instead of a manually releasable latch mechanism, the fifth wheel hitch
includes an automatic
adjustment device adapted to selectively move the fifth wheel hitch fore and
aft in response
to remote operator input.
3
CA 02309128 2000-04-23
In one method. an electric motor is mounted to a generally T-shaped support
brace
mounted between the upright assemblies. Distal ends of the upper. transverse
portion ot the
T-shaped brace are respectively attached to each of the pair of upright
assemblies. The center
portion of the T-brace includes both an outer and inner tubular member, where
the inner
tubular member is telescopically mounted within the outer member. A threaded
nut is
concentrically fixed in place within the inner tubular member, while a
threaded rod extends
concentrically within the outer tubular member. A first end of the threaded
rod threadedly
engages within the nut, while a second end of the rod is attached directlv to
a Qear reduction
box and the electric motor, both of which are attached directly to the vehicle
frame. To move
1o the fifth wheel hitch, the vehicle operator may selectively actuate the
motor to rotate the
threaded rod on its axis. As the rod turns, it is either drawn into or removed
from the fixed
nut (depending upon the direction of rotation), thereby forcing the inner
tubular member to
telescope into or be forced out of the outer tubular member. In this way, the
length of the
center portion of the T-shaped brace is shortened or lengthened, therebv
causing the attaclied
fifth wheel hitch to move fore or aft as desired.
The !zlider fifth wheel attachment assembly of the present invention allows
adjustment
of the fifth wheel hitch assemblv using rollers. As a result, the fifth wheel
trailer hitcli is
allowed to roll fore and aft. .c-hile the towed vehicle remains coupled to a
towing vehic'.z.
Advantageously, the glider fLih wheel attachment assembly rolls, ratlier than
slides. Binding
between the fifth wheel trailer hitch and the guide rails due to uneven
rolling or excessi\'e
friction is therefore entirelv eliminated. In the first embodiment, the
latching mechanism is
visible outside of the upright assemblies so that an end user may positively
identify when the
glider fifth wheel attachment assembly is locked in either a first or a second
position.
Moreover, the latching mechanism is preferably biased to a latched position in
either the first
or second position by means of a compression spring located on a first end of
the latching
4
CA 02309128 2000-04-23
bar. In this wav, shortcomintis of prior art adiustabie tifth wheel hitch
assemblies are
overcome.
The automatic version of the fifth wlleel Ilitch allows continuous adjustment
fore or
aft, and does not require that the vehicle operator exit the vehicle to
release or engage the
locking mechanism. Importantly, the towed vehicle may be towed with the hitch
set at any
point within the distance of travel of the adjustable device. Additionally,
adjustment of the
towed vehicle does not require any movement of the towina vehicle.
BRIEF DESCRIPTION OF THE DRAWINGS
The features and inventive aspects of the present invention will become more
apparent upon reading the following detailed description, claims, and
drawings, of which the
following is a brief description:
FIG. 1 is an exploded view of a fifth wheel trailer hitch incorporating the
glider fifth
wheel attaclunent assembly of the present invention.
FIG. 2 is a side x-iew of the glider fifth wheel attaclunent assembly of the
present
invention.
FIG. 3 is a side view of a portion of the 2lider fifth xvheel attachment
assembly of the
present invention.
FIG. 4 is an end view of Fiaure 3 showina the rollers of the present
invention.
FIG. 5 is a cross sectional view along lines 5-5 of Figure 1 showing the
latching
mechanism of the present invention.
FIG. 6 is an exploded view of a alider fifth wheel trailer hitch incorporating
an
automatic adjustment device.
CA 02309128 2000-04-23
FIG. 7 is a cross sectional view of the automatic adjustment device taken
along line 7-
7 of FIG. 6
DET AILED DESCRIPTION OF PREFERRED EvIBODIVIENTS
A fifth wheel hitch assembly 20 is shown in Figure 1 incorporating the glider
fifth
wheel attachment assembly 22 of the present invention. The hitch assembly 20
is generally
mounted on a support frame comprising a pair of spaced base rails 24 of
conventional desi=n
that are bolted or otherwise fastened to the frame of a motor vehicle in a
manner well known
in the art.
Accordina to the invention, a pair of spaced, parallel auide rails 26 are
mounted to
bridge between the base rails 24. The guide rails 26 therefore extend parallel
to the
longitudinal axis of the motor vehicle when properly mounted. Preferably, each
guide rail 26
is formed from a four-sided tube constructed from steel or other suitable hiah
strenath
material. If desired, an end cap 28 may be affixed to each free end 30 of the
guide rails 26.
As best seen in FiQure 2, each guide rail 26 further includes downwardly
extending tabs 32 at
pre-determined positions along the axial length of the guide rails 26. The
tabs 32 are
received within slots 34 (Figure 1) formed in the base rails 24. Once the tabs
32 are inserted
into proper slots 34, a connecting pin 36 is inserted through aligned,
cooperatinc, apertures
38 to capture the tab 32 and affix the guide rails 26 to the base rails 24,
thereby effecting
?o proper installation of both base rails 24 and guide rails 26.
According to the present invention, portions of the glider fifth wheel
attachment
assembly are mounted to the guide rails 26 before the guide rails 26 are
attached to the base
rails 24. As best seen in Figure 2, an upright assembly 40 is mounted to each
guide rail 26.
Each upright assembly 40 includes a lower sleeve portion 42 (see Figure 3), an
intermediate
housing portion 44, and an upper mounting portion 46. The guide rai126 is
inserted within
CA 02309128 2000-04-23
the sleeve portion 42 before beinQ attached to the base rails 24. Therefore,
it may be
appreciated that the sleeve portion 42 is sized to be slightly larger than the
dimensions of the
four-sided auide rails 26 so that the walls 43 of the sleeve portion 42 do not
interfere with
lonQitudinal movement of the upright assemblies along the guide rails 26.
The upper mounting portion 46 of the upright assembly 40 includes spaced bolt
holes
48 for mounting a cross-member or head support 50. Conventionally known head
supports
50 are height adjustable to enhance the versatility of the hitch assembly 20
in interconnecting
towins vehicles and towed vehicles of various heights and dimensions. A head
assembly 52
for receivina attachment means of a towed vehicle is attached to the head
supports 50. The
to head assembly 52 includes a jaw assembly 54 for releasably engaging a
kingpin (not shown)
of a to -ed vehicle (not shown). Jaw assemblies such as shown at reference 54
are well
known in the art. The head assembly 52 is also typically pivotally mounted to
the head
support 50.
To provide smooth adjustability, the glider fifth wheel attachment assembly of
the
present invention further includes at least one roller 56 mounted within each
liousinQ portion
44 of the upright assemblies 40. Preferably, as best seen in Figure 3, two
rollers 56 are
mounted -ithin the housinc, portion 44, with the rollers beins placed
adjacent the longitudinal
edQes of the upright assembly 40 for better support of the fifth wheel hitch
assembly.
Preferably, the rollers are fonned from a hard material capable of
withstanding the loading
forces of a towed vehicle while not adversely interacting with the guide rails
26. The rollers
56 contact an upper surface 58 of the -uide rails 26 to allow the glider fifth
wheel attachment
assemblv 22 to be easily moved between a first, or towing, position and a
second, or
maneuvering, position.
The alider fifth wheel attachment assembly is shown in the first, or towing,
position in
FiQure 1. Because the rollers 56 are installed using bolts 57, the side walls
68 of the housing
CA 02309128 2000-04-23
portion 44 may be compressed inwardly. To prevent excess compression, a tnetal
strap 45
may be formed between the sidewalls 68 parallel to an axis of rotation of the
rollers 56 to
limit the amount that the bolts 57 may be tightened.
The first, or towing, position preferably fixes the location of the head
assembly 52.
and therefore the load of the towed vehicle, substantially over the rear axle
and between the
rear wheels of the towing, vehicle. In this position, clearance between the
towed vehicle and
the towincr vehicle is minimized, but is within acceptable limits for normal
towing operations.
However, the clearance between the towing and towed vehicles when the location
of the head
assembly 52 is in the first position is often insufficient to allow precise
maneuvering within
to limited spaces such as those found in campgrounds or trailer parks. As a
result, maneuverins,
in limited spaces often causes undesirable contact between the towin; and
towed vehicles,
possible damagina either vehicle. To reduce the possibility of undesirable
interaction
bev,veen the towing and towed vehicles, the glider fifth wheel attaclunent
assembly 22 of the
present invention may be moved rearwardly to a second position bv the towing
vehicle
operator while the towed vehicle is still attached to the head assembly,
thereby increasing the
clearance between the towing and the towed vehicles.
In particular, as best seen in Figure 5, a latching mechanism 60 is used to
lock the
slider fifth wheel attachment assembly 22 of the present invention into either
the first or the
second positions. The latching mechanism 60 preferably includes a Qenerally L-
shaped bar
62 that is selectively rotatable between a first and a second position. The
bar 62 may be a
unitary piece, or it may include several pieces fastened tosether, as shown in
Figure 5. A first
end 64 of the bar 62 extends through aliQned apertures 66 formed in the
sidewalls 68 of the
housing portion 44. Preferably, the first end 64 extends benveen both upright
assemblies 40
perpendicular to the guide rails 26. At least one latch pin 70 is fixedly
mounted along the
first end 64 of the bar 62 such that the latch pin 70 is parallel and
laterally spaced from the
~
CA 02309128 2000-04-23
bar 62 axis of rotation (indicated generally by line 5-5 of Figure 1). As seen
in FiQure 5, the
latch pin 70 is preferably mounted adjacent to a side wall 43 of the sleeve
portion 42.
Importantly, the latch pin 70 is not hidden within the upright assembly 40,
but rather is in
plain view so that an operator may N-isibly confirm adequate latching. A
compression spring
; 72, mounted between an upright assemblv 40 and a shoulder 74 formed along
the bar first
end 64 resiliently biases the latching pin 70 into enuagement with either a
first latchinv liole
76 (see Figures 2 and 3), corresponding to a first position, or a second
latching hole 7 S.
corresponding to a second position. Both latching holes 76, 78 are formed in
the side wall 43
of the lower sleeve portion 42 -enerallv vertically below the aligned holes
66. Preferably,
1o pins 70 include a beveled tip 80 to enable easv insertion into the latching
holes 76, 7S.
In addition to engaging one of the latchin- holes 76,78, the latch pin 70 also
enQages
one of holes 84, 86 formed in the guide rails 26 that align with the latching
holes 776, 78.
Preferably, latching hole 76 aligns xvith hole 84 in the guide rail 26 when
the glider
attachment assembly 22 is in the first position for towing the fifth wheel
trailer. Likewise,
15 latching, hole 78 preferably aligns Nvith hole S6 in the guide rail 26 when
the glider attaclunent
assembly 22 is in the second position for maneuverinLy the fifth wheel trailer
in tight spaces.
-Artd when the glider fifth wheel attachment assemblv 22 is in either the
first or the second
position, the latching mechanism 60 ensures that the entire assembly is fixed
in place because
the latch pins 70 are inserted within the appropriate aligned holes. In a
preferred
20 embodiment, the first end 64 of the L-shaped bar is provided %vith a second
latch pin 70
adjacent to the second guide rail 26 that enQages corresponding holes in the
second vuide rail
that are aligned with holes 84 and S6 in the first 2uide rail.
The clider fifth wheel attachment assembly shown in Figure I is in the first
or towing
position, such that the head support _50 and the head assembly 52 are
positioned to%vards the
25 front of the towing, vehicle (not shown). The latching mechanism 60 is
rotated so that a
~
CA 02309128 2000-04-23
second end 57 of the L-shaped bar 62 points ;enerallv vertically, causin; the
latch pin 70 to
en,-,a-e the first latching liole 76, and in turn, the tirst auide rail hole
84 to secure the glider
assembly in place. In the first position. the glider attaclnnent assembly 22
distributes the
weight of the towed vehicle over the towing vehicle rear axle, thereby
achieving stable
towing under normal operation.
When required, however, the operator of the towing vehicle may simpiv and
easily
adjust the glider attachment assembly 2_2 to provide additional clearance
between the towing
vehicle and the towed vehicle to enhance the maneuverability of the towed
vehicle. To
achieve the additional clearance, the operator stops the towing vehicle and
manipulates the L-
shaped bar 62 of the latching mechanism 60. The L-shaped bar is first pulled
in a direction
awav from the glider assembly (to the left in Fieures 1 and 5), thereby
compressing the spring
72 and removing the latch pins 70 from within holes 76 and 84. The operator
then pivots the
L-shaped bar 62 in a direction away from the towed vehicle (i.e.
counterclockwise), thereby
moving the latch pins 70 from the first position to a second position engaged
within hole 78
on the lower sleeve portion of the upriQht assembly 40. Because the latching
hole 78 is not
immediately aligned with the second hole 86, the alider assembly is allowed to
smoothly roll
reanvardly of the towing vehicle on the rollers 56. causing the towed vehicle
to move
baclcxvardly and away from the towinc, vehicle a predetermined amount. To
accomplish the
movement of the glider attachment assembly, the towed vehicle may be manually
pushed
backwardly while the towing vehicle remains stationary if the towed vehicle is
on an
appropriately smooth and level surface. Alternatively, the operator may move
the towing
vehicle forward while enoaoing the brakes of the towed vehicle to accomplish
movement of
the alider attachment assembly. Once the latch pins 70 are disengaged, the
rollers 56 allow
such a smooth transition between first and second positions that often only
manually applied
CA 02309128 2000-04-23
force is necessary to move the glider assembly, whereas prior art adjustable
fifth wheel hitch
assemblies require moving the towing vehicle fonvard.
Because the latch pins 70 are resiliently biased by the compression spring 72,
once the
second guide rail hole 86 becomes aligned with the second latch hole 78 after
the glider
assembly has moved the predetermined amount, the latch pins 70 snap into
place, thereby
locking the glider attachment assembly 22 against further rearward movement.
In this way,
the Qlider attachment assembly becomes locked in a second position, where
additional
clearance is provided betNveen the towinc, vehicle and the towed vehicle.
Preferably, the
glider attachment assembly is allowed to move between 6 and 10 inches
reanvardly. vlost
1o preferably, the glider attachment assembly 22 allows for 9.5 inches of
travel between the first
and the second positions. The added space or clearance between the towing and
the towed
vehicles allows for sharp turning so that the operator may negotiate tight
spaces where
maneuverability is required.
It should be noted that the reverse procedure applies to return the glider
attachment
assembly 22 to the first position. Thus, when enhanced maneuverability is no
longer
required, the operator pulls the L-shaped bar 62 away from the glider
attachment assembly
and rotates it clockwise so that the latch pins engage the first latchin; hole
76. The toNved
vehicle is then moved towards the towincy, vehicle until the resiliently
biased latch pins 70
additionally engage the first guide rail holes 84.
The rollers 56 of the present invention therefore provide significant
advantages over
the prior art. In particular, the fifth wheel trailer hitch is allowed to roll
fore and aft, while
the towed vehicle remains coupled to a towina vehicle without suffering from
binding due to
excessive friction or metal to metal binding caused by wear and compression of
low friction
shoes. Thus, binding betNveen the fifth wheel trailer hitch and the guide
rails due to uneven
z5 rollinz or excessive friction is eliminated. Moreover, in the preferred
embodiment, the
Il
CA 02309128 2000-04-23
latching mechanism 60, comprising an L-shaped bar 62 and latch pins 70, is
visible outside of
the upriuht assemblies so that an operator may positively identify when the
glider fifth wheel
attachment assembly 22 is locked against movement in either a first or a
second position.
The glider attachment assembly 22 of the present invention mav also be used
with any
~ commercially available fifth wheel hitch assembly to convert the fifth wheel
hitch into an
adjustable assembly capable of moving between a first and a second towinla-,
position. Thus,
the present invention solves all problems present in prior art adjustable
fiftli wheel trailer
hitch assemblies.
A second embodiment of the glider attachment includes a remotely actuated
adjustment device and is shown in FIGS. 6-7. The power-actuated hitch assembly
120 shown
in FIGS. 6-7 includes many of the same components that have been previously
described,
which are numbered accordinalv. Therefore those components will not be
described aQain.
In the second embodiment, the assembly 120 does not include a latching device
such
as device 60 in FIG. 5. Instead, the latching assembly has been replaced with
an automatic
adjustment device 130 mounted between the upright assemblies 40. While the
adjustment
device 130 may include any type of powered assembly, including a compressed
fluid device
(i.e. hydraulic or pneumatic), device 130 is preferably powered by an electric
motor 132 in
combination with a alear box 134. Power is provided to the motor from the
vehicle through a
cable 136, which may also provide control instructions from the vehicle
operator from a
?o separate console mounted within the vehicle cab (not shown). I'Motor 132 is
also connected to
a generally T-shaped support brace 138 having a center portion 140 and a
transverse bar 142.
The distal ends 144 of transverse bar 142 are respectively mounted to one each
of the upright
assemblies 40 to ensure that the assemblies 140 maintain the proper spacing
and alienment.
Transverse bar may be constructed in anv confiLluration, but bar 142 is shown
in FIGS. 6-7
as havina a square cross-section to resist torsion. As mav be appreciated,
since bar 142 is
l ~-.
CA 02309128 2000-04-23
attached to the upright assemblies 40. if the bar 142 is moved fore and aft,
then assemblies 40
(and the hitch head assembly 52) will also be forced to move fore and aft.
To provide such fore and aft movement, bar 142 is attached at a point
intermediate
each end 144 to the center portion 140 of T-shaped brace 138. Center portion
140 includes
two hollow tubes telescopingly and concentrically interfitted to accommodate
fore and aft
movement of bar 142. In particular, center portion 140 includes an buter
support tube 146
and an inner support tube 148. As best seen in FIG. 7, an outer diameter Di of
inner tube 148
is smaller than an inner diameter D, of outer tube 146, therebv allowing inner
support tube
148 to telescopingly slide within outer support tube 146. Outer tube 146 is
attached at a first
1o end 150 to an e:cternal housinQ 152 of gear box 134. If necessary, a flange
154 may be
affixed to end 150 of tube 146 to provide greater support and easier mounting
to Qear box
134. A drivable shaft 160 extends from gear box 134 through the flange 154
alonQ center
axis A of tube 146 that terminates in a threaded rod 162. As seen in FIG. 7,
threaded rod 162
extends along center axis A substantiallv the entire axial length of tube 146.
A baffle 164
may be added adjacent to end 150 and slightly spaced therefrom to provide
additional support
to rod 162 and to enclose thrust bearings 166 mounted about the external
circumference of
shaft 160. Bearings 166 are conventionally mounted, and may be separated by a
tlange 168
on shaft 160 intermediate flange 154 and baffle 164.
Similarly, a first end 168 of inner tube 148 is attached to an intermediate
portion of
bar 142 in any conventionally accepted manner. As seen in FIG. 7, tube 148 is
preferably
attached by inserting an end portion 170 through an appropriately sized
aperture 172 in bar
142 and welding bar 142 and tube 148 together. Additional support is provided
by gussets
174 welded in place to prevent torsional movement of tube 14S relative to bar
142. As noted
above, tube 148 is hollow and sized to receive threaded rod 162. A threaded
nut 176 is
concentrically mounted inside second end 178 of tube 148. Rod 162 is
threadedh. received in
l3
CA 02309128 2000-04-23
nut 176. Since tube 148 is telescopically received witllin tube 146, tube 148
moves into and
out of tube 146 in response to rotation of rod 162, therebv increasing or
decreasing the
distance X between qear box 134 and bar 138.
To properly accomplish movement of bar 138 relative to rails 24 using motor
132,
motion of the motor must be eliminated. Relative motion of the motor is
eliminated by
fastening the motor down to rails 24. Preferably, outer tube 146, to which
motor 132 is
directly attached, is welded to a support bracket 180 that is in turn mounted
directly to rails
24. Of course, any portion of the motor/gear box assembly may be fastened in
place using
any conventional means without departing from the invention.
Since the bar 138 is directly attached to uprights =10. -hich include rollers
56 for
rolling on 2uide rails 26, fonvard and rearward motion of bar 138 will also
move uprights 40
forward or reanvard relative to the vehicle body, thereby selectively and
adjustably
positioninv the fifth wheel attachment according to the desires of the
operator. Additionally,
since tlireaded rod 162 will not rotate about its axis without input from the
vehicle operator,
once the operator has positioned the fifth wheel hitch, the threaded rod will
prevent unwanted
forward or rearward movement of the hitch. As a result, the latching mechanism
60
described above is no longer necessary. Since the latching mechanism is
eliminated, the
vehicle operator no longer need exit the vehicle to unlatch the fifth wheel
hitch. and instead
may accomplish a full range of fore and aft motion of the hitch from the
safety and comfort
of the vehicle cab. Finally, since the threaded rod acts in lieu of the latch,
the fifth wheel
hitch of the present invention is capable of towing along a continuum between
the fully
forward position of the hitch and the fully reanvard position of the hitch.
The relative
position of the towed vehicle with respect to the towing vehicle may therefore
be optimized
by the vehicle operator anywhere along the hitch distance of travel.
~4
CA 02309128 2000-04-23
Preferred embodiments of the present invention have been disclosed. A person
of
ordinary skill in the art will realize, however, that certain modifications
and alternative forms
will come within the teachings of this invention. Therefore, the following
claims sliould be
studied to determine the true scope and content of the invention.
IS
