Note: Descriptions are shown in the official language in which they were submitted.
21 880 69
SAFETY STAND FOR TRAILER LOADING
MELD OF INVEN 11UN
This invention in the preferred embodiment relates to tractor trailers and
specifically to
so-called "spotted" trailers which have been decoupled from the tractor at a
loading dock and
which will be secured in a position by a safety locking device which engages
the kingpin
normally engaged by the tractor.
BACKGROLINI) OF THE INVENTION
It is known in the trucking industry to "spot" a trailer by decoupling the
tractor from the
trailer after the trailer is positioned at a loading dock. A kingpin is
provided adjacent the front
bottom portion of the trailer whose construction is well known in the art.
Typically the tractor
includes a biased coupling plate (fifth wheel) for latching engagement with
the kingpin.
However, with the trailer spotted, the kingpin is exposed, and the front end
of the trailer is thus
unsupported.
Because of this lack of support, there are typically provided support members
known as
"landing gear" and disposed along the body of a trailer towards the front of a
trailer. The landing
gear is typically cranked down to engage the ground so as to enable the
trailer to be disengaged
from the tractor. The landing gear is then intended to remain in engagement
with the ground to
keep the trailer from toppling over.
When a spotted trailer is located at the dock if loaded in a conventional
manner, for
example by a fork truck, the fork truck may drive forward past the cranked
down landing gear
and hence risk toppling or "nose-diving" the trailer. Jack stands therefore
may be provided
adjacent the front of the trailer. However these are manually operated stands
which are
positioned near each edge of the front of the trailer before loading. Unless
these jack stands
engage the metal plate reinforcement surrounding the kingpin or engage the
kingpin itself then
there is the risk of the failure of the stand or the trailer during loading
and resulting nose-diving
of the trailer. For example if the jack stands engage the floor channel of the
trailer, which
21 680 69
channels may be corroded, or the wooden floor boards of the trailer, depending
on the load
distribution an accident may occur.
It would therefore be advantageous to provide a more substantial and
preferably centrally
disposed support for the trailer proximate the front end thereof, which
support would engage
adjacent to the metal plate reinforcement surrounding the kingpin or engage
the kingpin itself,
which pin is normally engaged by the tractor, and thereby prevent the trailer
from nose-diving
or alternatively tail diving (if the rear wheels of the trailer are positioned
so as to provide a
considerable overhang toward the rear of the trailer) during normal loading.
United States Patent 5,165,265 provides, in combination with a security lock,
support legs
for engaging the support surface adjacent the forward end of an associated
trailer.
United States Patent 4,014,517 describes one example of a stand for supporting
a
1 S structure such as a mobile home above the ground. The stand includes a
flat broad base for
engaging the ground and a plurality of legs assembled to the base. The legs
converge from the
base to a support 22 so that the support platform may be positioned in a firm
supportive
relationship to the structure. Manual operation of a handle 63 provides for
the hydraulic jacking
of the support 22 to engage a structural member of the mobile home or the
like.
United States Patent 4,169,579 provides a support assembly for supporting a
tongue of
a trailer and adjustable to establish the tongue at a desired elevation from
the ground so as to
enhance hitching to a towing vehicle.
Nowhere in the prior art is there provided a collapsible, (for example
folding), safety
stand for engagement in one position, for example to the kingpin of an
unfettered or spotted
trailer or the like.or that may be positioned adjacent the kingpin of the
trailer proximate the
reinforcing plate provided with the kingpin to provide prevention of nose-
diving of the trailer
during loading or unloading and which safety device may be alternatively
positioned in a flat
stored position to allow a tractor access for hitching the trailer.
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21 680 69
It is therefore a primary object of the invention to provide a collapsible
(for example
folding), trailer safety stand which is located in the bay in which a trailer
is normally docked.
It is a further object of the invention to provide a collapsible (for example
folding), safety
stand which has a portion which engages adjacent to or to the kingpin of an
unfettered or spotted
trailer, which is normally engaged by a tractor when locating the trailer in a
docked position.
It is yet a further object of the invention to provide a collapsible (for
example folding),
safety stand which has a moveable portion which engages adjacent to, or to the
kingpin of an
unfettered or spotted trailer, which is normally engaged by a tractor when
locating the trailer in
the docked position. The moveable portion may further accommodate various
lengths of trailers.
Further and other objects of the invention will become apparent to those
skilled in the art
when considering the following summary of the invention and the more detailed
description of
the preferred embodiments illustrated herein.
SUMMARY OF THE INVENTION
According to a primary aspect of the invention there is provided a collapsible
trailer
safety stand comprising a base locatable adjacent the front of a loading bay a
predetermined
distance away from a dock so as to be located adjacent the kingpin of an
unfettered or spotted
trailer, the kingpin normally being engaged by a tractor and the unfettered or
spotted trailer being
positioned in the loading bay adjacent to the dock when the trailer is
disconnected from the
tractor. The collapsible safety stand has a top and bottom and a base located
proximate its
bottom, the base having pivotally attached thereto at least one lifting arm
and at least one
stabilizing arm, said an~ns having pivotally attached therewith a support, and
preferably a kingpin
engaging mechanism, disposed proximate the end of said arms remote the base.
The support is
moveable from a first position wherein the support is disposed substantially
within the base
whereat the safety stand lays substantially flat in the loading bay so as not
to interfere with the
movement of a tractor trailer when decoupling the trailer, to a second
position wherein the
support is disposed adjacent the kingpin. The support is also preferably
movable to a third
position wherein, when the support is a kingpin engaging mechanism, the
support locks the
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trailer in a locked position. In such a position, the arms are disposed at an
angle greater than
ninety degrees from the first position, and the support engages against the
kingpin with a force
su~cient to prevent the forward motion of the trailer, to lock the trailer
substantially in the dock
of the loading bay when the trailer is docked. The arms are engaged with a
drive (preferably a
S hydraulic cylinder or a pneumatic cylinder or mechanical/electric drive) to
drive said support
from the first position to the second position locating the mechanism adjacent
to said kingpin of
said tractor trailer, (and preferably to said third locked position when the
support engages the
kingpin) whereby the collapsible safety stand prevents nose-diving of the
trailer when the trailer
is being loaded or unloaded by conventional means. For example, if a fork
truck were to drive
in an empty trailer toward the front thereof adjacent to the kingpin past the
landing gear supports
provided along the body of a trailer towards the front of a trailer which are
cranked down to
engage the ground, depending on the method of loading of the trailer, there is
a risk of
overturning the trailer. By using the trailer safety stand such a problem is
obviated, especially
when the support engages the kingpin since only slight lateral movement is
possible.
In a preferred embodiment of the invention when the support engages the
kingpin, the
support has a generally V-shaped notch provided therewith to engage the
kingpin in order to
locate the kingpin as close to the notch as possible when the support moves to
the third position.
The V-shaped notch will provide, during movement from the second to the third
position, a
constant caroming force tending to center the kingpin of the trailer in the
support as the support
pushes against the kingpin at the third position. The trailer may therefore
initially or during
progressive stages of loading be moved laterally as a result of said constant
force, regardless of
the point of engagement of the generally V-shaped notch with the kingpin,
within the boundaries
of the support.
In one embodiment the at least one stabilizing ann is offset toward the end of
the support
not having the generally V-shaped notch therein. The support therefore having
the generally V-
shaped notch provides a constant caroming force resulting in the shifting of a
trailer toward the
center line of the bay if the trailer was not already properly positioned by
the tractor at that point.
Further by preferably having the support engage the kingpin, normally engaged
by the tractor,
in the second position, further movement of the support to the third position
may under the
21 680 69
constant force exerted drive the trailer back toward the dock if the trailer
is empty or in the
process of being unloaded, wherein the third position becomes a locking
position preventing
forward movement of the trailer against the constant force applied by the
safety stand.
According to yet another aspect of the invention there is provided a
collapsible trailer
safety stand to be located adjacent the kingpin of an unfettered or spotted
trailer the kingpin
being surrounded by a mounting plate and normally engaged by the tractor of
the vehicle. In this
embodiment, the collapsible trailer safety stand includes a stationary base
having two ends and
having at least one rail or channel extending from proximate one end to
proximate the other end.
It also includes a sled that is moveable within said base from proximate one
end to
proximate the other end of said base, the sled having side members and bearing
members
extending laterally away from the side members thereof in engagement with the
at least one rail
or channel of said base. The bearing members are thus prevented from leaving
the at least one
1 S rail or channel by the side members of the sled and the at least one rail
or channel.
The base preferably includes a multiplicity of stop positions for the sled
between the ends
of the base, for example to allow for various unfettered trailer lengths.
The sled has pivotally attached thereto at least one lifting arm and at least
one stabilizing
arm, said arms having pivotally attached therewith a support, and preferably a
kingpin engaging
mechanism, disposed proximate the end of said arms remote said base and being
moveable from
a first position wherein the support is disposed substantially within the
sled, whereat the support
lays substantially flat in the sled so as not to interfere with the movement
of a tractor trailer when
decoupling the trailer, to a second position wherein the support is disposed
adjacent-the kingpin.
The support is also preferably movable to a third position wherein, when the
support is a kingpin
engaging mechanism, the support locks the trailer in a locked position. In
such a position the
arms are disposed at an angle greater than ninety degrees from the first
position, and the support
engages against the kingpin with a force sufficient to prevent the forward
motion of the trailer
to lock the trailer substantially in the dock of the loading bay when the
trailer is docked. The
arms are engaged with a drive (preferably a hydraulic cylinder or a pneumatic
cylinder or a
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21 680 fig
mechanical/electrical drive) to drive said support from the first position to
the second position
locating the support adjacent to said kingpin of said tractor trailer, (and
preferably to said third
position when the support locks the kingpin).
The sled is moveable within the base, when the support is in the first stored
position, to
and from proximate the trailer by a second drive preferably engaged with one
of the bearing
members on the sled to locate the sled at one of the preferred multiplicity of
stop positions
proximate the nose of the unfettered trailer for any size trailer so that the
support is able to
accurately move at least to the second position. For this purpose, the sled
has a sensor in
communication with the drive to sense when the sled is adjacent the nose of
the unfettered trailer
to locate the sled at a position consistent with the length of the trailer
such that when the support
moves it will be in the correct second position and preferably be at the
kingpin engaging position.
This embodiment preferably includes means for locking the sled at the
multiplicity of
stop positions when the support is moved to the second position. Preferably
the second drive is
a hydraulic cylinder having a tab extending from the pivot thereof remote the
support which will
not interfere with the motion of the sled when the support is in the first
position but which will
engage a predetermined portion of the base at each of the multiplicity of stop
positions when the
support moves to the second position (preferably engaging a flat plate
interconnecting the sides
of the base proximate each stop position).
This embodiment of the collapsible safety stand, when in the second or
preferred third
position, thus prevents nose-diving of the trailer when the trailer is being
loaded by conventional
means.
In one embodiment when the first drive is a hydraulic cylinder a hose reel is
provided
with the stationary base proximate the end of the base remote the trailer
which hose reel takes
up and lets out hose as the sled moves toward or away from the unfettered
trailer. In another
embodiment when the second drive is a hydraulic motor, a cable reel is
provided with the
stationary base proximate the end of the base remote the trailer which cable
reel takes up and lets
out cable as the sled moves toward or away from the unfettered trailer.
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21 680 69
In a preferred embodiment of the invention when the support engages the
kingpin, the
support has a generally V-shaped notch provided therewith to engage the
kingpin in order to
locate the kingpin as close to the notch as possible when the support moves to
the third position.
The V-shaped notch will provide, during movement from the second to the third
position, a
S constant caroming force tending to center the kingpin of the trailer in the
support as the support
pushes against the kingpin to the third position. The trailer may therefore be
initially or during
progressive stages of unloading moved laterally as a result of said constant
caroming force,
regardless of the point of engagement of the generally V-shaped notch with the
kingpin, within
the boundaries of the support.
In one embodiment the at least one stabilizing arm is offset toward the end of
the support
not having the generally V-shaped notch therein. The support therefore having
the generally V-
shaped notch thus provides a constant caroming force resulting in the shifting
of a trailer toward
the center line of the bay if the trailer was not already properly positioned
by the tractor at that
point. Further by preferably having the support engage the kingpin, normally
engaged by the
tractor, in the second position, further movement of the support to the third
position may under
the constant force exerted drive the trailer back toward the dock if the
trailer is empty or in the
process of being unloaded, wherein the third position becomes a preferred
locking position
preventing forward movement of the trailer against the constant force applied
by the safety stand.
According to yet another aspect of the invention there is provided a
collapsible machine
including a stationary base having two ends and having at least one rail or
channel extending
from proximate one end to proximate the other end.
The machine includes a sled moveable within said base from proximate one end
to
proximate the other end of said base, said sled having side members and
bearing members
extending laterally away from the side members thereof into engagement with
the at least one
rail or channel of said base, the bearing members thus being prevented from
leaving the at least
one rail or channel by the side members of the sled and the at least one rail
or channel.
21 890 69
The base preferably includes a multiplicity of stop positions for the sled
between the ends
of the base.
The sled has pivotally attached thereto at least one lifting arm and at least
one stabilizing
arm, said arms having pivotally attached therewith a support disposed
proximate the end of said
arms remote said base and being moveable from a first position wherein the
support is disposed
substantially within the sled, whereat the support lays substantially flat in
the sled, to a second
position wherein the support is disposed a vertical distance from the sled and
the base. The
support is also preferably movable to a third position whereat said arms are
disposed at an angle
greater than ninety degrees from the first position when laying flat in the
sled. The arms are
engaged with a drive (preferably a hydraulic cylinder or a pneumatic cylinder
or a
mechanical/electrical drive) to drive said support from the first position to
the second position
and preferably to said third position.
The sled is moveable within the base between the ends thereof, when the
support is in the
first stored position, to and from proximate a predetermined position by a
second drive preferably
engaged with one of the bearing members to locate the sled at one of the
preferred multiplicity
of stop positions so that the support is able to accurately move at least to
the second position.
The sled includes a sensor in communication with the drive to sense when the
sled is adjacent
the predetermined position to locate the sled thereat such that when the
support moves it will be
in the correct second position.
This embodiment preferably includes means for locking the sled at the
multiplicity of
stop positions when the support is moved to the second position, preferably
the second drive is
a hydraulic cylinder having a tab or clip extending from the pivot thereof
remote the support
which will not interfere with the motion of the sled when the support is in
the first position but
which engages a predetermined portion of the base at each of the multiplicity
of stop positions
when the support moves to the second position (preferably engaging a flat
plate interconnecting
the sides of the base proximate each stop position).
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21 680 69
This embodiment of the collapsible machine, when in the second or preferred
third
position, may thus be used as a safety stand.
In one embodiment when the first drive is a hydraulic cylinder a hose reel is
provided
with the stationary base proximate the end of the base which hose reel takes
up and lets out hose
as the sled moves between the ends of the base. In another embodiment when the
second drive
is a hydraulic motor a cable reel is provided with the stationary base
proximate the end of the
base which cable reel takes up and lets out cable as the sled moves between
the ends of the base.
According to yet another aspect of the invention there is provided a
collapsible machine
having located proximate its bottom a base having pivotally attached thereto
at least one lifting
arm and at least one stabilizing arm, said arms having pivotally attached
therewith a support
disposed proximate the end of said arms remote said base and being moveable
from a first
position wherein the support is disposed substantially within the base whereat
the mechanism
lays substantially flat, to a second position wherein the support is disposed
a vertical distance
from the base. The support is also preferably movable to a third position
whereat said arms are
disposed at an angle greater than ninety degrees from the first position when
laying flat in the
base. The arms are engaged with a drive (preferably a hydraulic cylinder or a
pneumatic
cylinder) to drive said support from the first position to the second position
and preferably to said
third position whereby the machine when in the second or preferred third
position may be used
as a safety stand.
In a preferred embodiment of the inventions described in the above paragraphs
the at least
one stabilizing arm and the at least one lifting arm cooperate to maintain the
support substantially
horizontal at all times whether in the first, second, or third positions or
moving therebetween.
More particularly, this invention provides, a collapsible trailer safety stand
to be
located adjacent the kingpin of an unfettered trailer, the kingpin being
normally
engaged by the tractor of the vehicle, the collapsible trailer safety stand
comprising:
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21 680 69
- a stationary base having first and second ends and having at least one rail
extending the length of the base,
- a sled moveable within the base between the first and second ends of the
base,
the sled having side members, and bearing members extending laterally away
from the
side members and into engagement with the at least one rail of the base, the
bearing
members being prevented from leaving the at least one rail by the side members
of the
sled and the at least one rail,
- the base including a plurality of reinforcing members defining stop
positions for
the sled between the ends of the base, to allow for various unfettered trailer
lengths,
- the sled having pivotally attached thereto at least one lifting arm and at
least one
stabilizing arm, each of the at least one lifting and stabilizing arms having
a proximal
end pivotally attached to the sled, and a distal end, the arms having
pivotally attached,
at their respective distal ends, a support, the arms and the support being
moveable from
a first position wherein the support is disposed substantially flat within the
sled so as
not to interfere with the movement of the trailer, to a second position
wherein the
support is disposed adjacent the kingpin, the at least one lifting and
stabilizing arms
being engaged with a first drive, which drives the arms to move the support
from the
first position to the second position located the support adjacent to the
kingpin of the
trailer,
- the sled being moveable within the base, when the support is in the first
stored
position, to and from proximate the trailer by a second drive to locate the
sled at one of
the stop positions proximate the nose of the unfettered trailer for any size
trailer so that
the support is able to accurately move at least to the second position,
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21 680 69
- whereby the collapsible safety stand when in the second position prevents
nose
diving of the trailer when the trailer is being loaded or unloaded.
Further, this invention provides a collapsible machine comprising:
- a stationary base having first and second ends and having at least one rail
extending the length of the base,
- a sled moveable within the base between the first and second ends of the
base,
the sled having side members, and bearing members extending laterally away
from the
side members and into engagement with the at least one rail of the base, the
bearing
members being prevented from leaving the at least one rail by the side members
of the
sled and the at least one rail,
- the base including a plurality of reinforcing members defining stop
positions for
the sled between the ends of the base,
- the sled having pivotally attached thereto at least one lifting arm and at
least one
stabilizing arm, each of the at least one lifting and stabilizing arms having
a proximal
end pivotally attached to the sled, and a distal end, the arms having
pivotally attached,
at their respective distal ends, a support, the arms and the support being
moveable from
a first position wherein the support is disposed substantially flat within the
sled, to a
second position wherein the support is disposed a vertical distance from the
sled and the
base, the at least one lifting and stabilizing arms being engaged with a first
drive, which
drives the arms to move the support from the first position to the second
position,
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21 68069
- the sled being moveable within the base, when the support is in the first
stored
position, to and from proximate a predetermined position by a second drive to
locate
the sled at one of the stop positions so that the support is able to
accurately move at
least to the second position,
- whereby the machine when in the second position may be used as a safety
stand.
In addition, this invention provides a collapsible trailer safety stand for
engaging
an unfettered trailer adjacent the kingpin thereof, the kingpin being disposed
adjacent
the nose of the trailer, the safety stand comprising:
- a base having first and second ends,
- a sled movable along the base between the first and second ends thereof,
- a supporting assembly carried on the sled and movable relative to the base
between a collapsed, stored position, wherein the supporting assembly is
disposed
substantially flat within the base, and raised, supporting position, in which
a portion of
the supporting assembly is disposed vertically above the base to engage and
support the
trailer adjacent the kingpin thereof,
- a sensor for sensing the nose of the trailer, the sensor being operatively
connected to the sled and the supporting assembly such that the supporting
assembly
remains in the stored position as it moves with the sled relative to the base
between the
first and second ends of the base, and moves to the supporting position in
response to
the sensor sensing the nose of the trailer, such that the supporting assembly
is properly
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21 680 69
positioned adjacent the kingpin of the trailer to support the front nose of
the trailer
when the supporting assembly is in the supporting position.
Furthermore, this invention provides a method for supporting the nose of an
unfettered trailer disposed on a surface adjacent a loading bay, comprising
the steps of:
- providing a sled movable along the surface relative to the nose of the
trailer, and
carrying a supporting assembly movable between a stored, collapsed position
wherein
the supporting assembly does not interfere with movement of vehicles over the
surface,
and a raised, engaging position in which a portion of the supporting assembly
is
disposed vertically above the surface and engages and supports the nose of the
trailer;
- moving the sled along the surface and relative to the nose of the trailer
with the
supporting assembly in the stored position,
- sensing the nose of the trailer with a sensor carried on the sled,
- in response, moving the supporting assembly from the stored position to the
raised engaging position to support the nose of the trailer.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a side plan view of the support illustrated in its collapsed,
first
position, and illustrated in a preferred embodiment of the invention.
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21 680 69
Figure 1A is a schematic view of the support of Figure 1 illustrated in a
loading bay
occupied by a trailer and illustrated in a preferred embodiment of the
invention.
Figure 2 is a side elevation view of the support of Figure 1 shown in a second
preferred
position prior to engaging the kingpin of a trailer and illustrated in the
preferred embodiment of
the invention.
Figure 3 is a schematic view of the support when engaging the kingpin of the
trailer
illustrated in an alternative embodiment of the invention to Figure 2.
Figure 4 is a view similar to Figures 2 and 3 illustrating the final or third
position of the
support illustrated in a preferred embodiment of the 10 invention.
Figure 5 is a top plan view of the invention illustrating a centering feature
of the support
1 S and illustrated in a preferred embodiment of the invention.
Figure 6 is a side schematic view of a preferred embodiment of the invention
similar to
that described in relation to Figures 1 through 5 with the exception that the
base includes
therewith a moveable sled which houses the kingpin support, illustrated in a
preferred
embodiment of the invention.
Figure 7 is a top schematic view of the base 105 of Figure 6 illustrated in a
preferred
embodiment of the invention.
Figure 8 is a top schematic view of the sled of Figure 6 illustrated in a
preferred
embodiment of the invention.
Figure 9 is a top perspective view of the entire mechanism of Figure 6
illustrated in a
preferred embodiment of the invention.
Figure 9A is a side view of Figure 9.
z~ s8o ss
Figure 9B is an end view of Figure 9.
Figure 10 is a perspective view of the sled of Figure 8 illustrated in a
raised position in
a preferred embodiment of the invention.
Figure 11 is an exploded perspective view of the mechanism illustrated in
Figures 6
through 10 and illustrated in a preferred embodiment of the invention.
Figure 11A is a detail of a portion of Fig. 11.
Referring generally to Figures 1 through 5 there is illustrated a collapsible
supporting
device or trailer safety stand 10 located in loading bay B as shown in Figure
1 and Figure lA.
The trailer is supported upon a surface S on supports or "landing gear" W
after the tractor has
disengaged therefrom. The collapsible supporting device 10 is located on the
surface S and is
moveable from a first collapsed position substantially shown in Figures 1 and
lA to a raised
position shown in Figure 2 and 3 and finally to a locked position as shown in
Figure 4. In one
embodiment the collapsible safety support stand may be anchored to the ground
via baseplates
5 and 45. The baseplate 5 has pivotally attached thereto at pivot 20A lifting
arms 20. A
stabilizing arm 21 is pivotally attached to the baseplate 5 at pivot 21A. A
support plate 30
substantially as seen in Figure S is provided for engagement with the kingpin
P normally engaged
by the tractor. The plate 30 is pivotally attached to the two lifting arms 20
at pivots 20B and to
the supporting arm 21 at pivot 21B. The two lifting arms and the stabilizing
arm 20 and 21
respectively are aligned substantially parallel to one another during the
phases of motion of the
supporting device. A hydraulic cylinder 40 pivotally attached at 40A to
baseplate 45 is provided
for moving the arm 20 to and from the initial collapsed position seen in
Figure 1 to the final
raised position best seen in Figure 4. The rod 41 of cylinder 40 is attached
to a piston 47 which
is moved by hydraulic fluid in conventional manner. The extension therefore of
the cylinder
from its first collapsed position of Figure 1 wherein the arm is substantially
flat to a raised
position as seen in Figure 2 wherein the lifting arm and a stabilizing arm are
substantially at an
angle less than 90 degrees in relation to the baseplate 5. The piston rod 41
is attached to one of
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21 680 69
the arms 20 at a pivot 40B. The pivot 40B passes through a link 6. The pivot
40B is located
proximate the narrow end of link 6 and a torque tube TT passes between both
lifting arms 20 to
interlock the two arms and to ensure that the motion of the cylinders is
passed to both arms. The
plate 30 is attached proximate the top of the lifting and stabilizing arms 20,
21 and engages the
S kingpin P as best seen in Figure 4 preferably when arms 20, 21 are disposed
at an angle greater
than 90 degrees to the baseplate 5. (It may engage the kingpin at any angle
with effective
results.) In this position, the plate 30 pushes against the kingpin P as best
seen in Figure 5 so that
the kingpin P may substantially move toward a centered position within the
notch 35, plate 30
thereby moving the trailer T laterally to a substantially centered position
within the bay. The
trailer T may also be pressed substantially against the dock by the motion of
the support of the
collapsible safety stand to the preferred third position of Figure 4 thereby
providing a constant
force against the trailer and locking the trailer from moving away from the
dock since it cannot
move forward against the constant force of the cylinder 40. (Throughout this
disclosure the
meaning of locked is defined in this manner.)
The trailer is then ready to safely load without the risk of turning over the
trailer in a
direction D should the safety support stand not be present.
Referring specifically to Figures 6 through 11, there is illustrated another
preferred
embodiment of the inventive safety stand 100. The advantage of Figures 6
through 11 over the
previously described embodiment is that the design of the safety stand 100
will accommodate
various lengths of trailers. For example, it is well known that trailers have
various lengths of 40',
45', 48' and 53'. The present embodiment endeavors to provide a mechanism
which will, when
installed in a loading bay, compensate for the length of the trailer and
preferably be locked in
position once raised into engagement with the kingpin.
Figure 6 specifically refers to a trailer T which has been positioned and
uncoupled from
its tractor in a loading bay on a surface. In this regard, please refer to
Figure lA. However, in
this embodiment, the trailer may not be a fixed length, and therefore the base
105 must provide
for a certain amount of flexibility in positioning the support 130 in relation
to the kingpin P of
the trailer. The kingpin typically has a supporting plate surrounding it to
provide secure
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21 680 69
anchoring of the kingpin into the trailer. Such structures are well known in
the art, and the reader
is referred to those structures for further information in relation to the
kingpin. Typically, a
trailer is best engaged at the kingpin by my safety stand. Alternatively, my
safety stand could
be positioned adjacent a kingpin, but in doing so would not provide the
locking feature, but
S would prevent severe nose-diving of the trailer.
Referring therefore to Figures 6 through 11, there is provided a base 105
which is set in
position in a loading bay parallel to the loading bay. As best seen in Figure
9A and B, the base
105 has a low profile which may be traversed by the wheels of a tractor when
positioning the
trailer. Therefore, it is highly recommended that the base 105 be structured
of substantial
material sufficiently rugged to withstand the pounding that the trucking
industry would impart
upon such a device. All components of this system are recommended to be of
such a structure.
The base contains a front end lOSA and a rear end l OSB. The front end 1 OSA
of the base 105
includes a notch 106 wherein a hose reel Rl and cable reel R2 lets out and
takes up hydraulic
hose H and electric cable E as best seen in relation to Figure 11. The hose
reels Rl and R2
therefore let out and takes up hydraulic hose H and electric cable E to feed
the cylinders 140 and
drive M in a conventional manner. A cover member 112 is provided to protect
these components
from the elements. The base 105 has located along the length thereof
reinforcing members 253,
248, 245 and 240 corresponding to the length of the trailer being docked in
position. As best
seen in Figure 11, these flat bar elements are ai~'ixed by fasteners Fl at
respective openings O 1
within the side channels C 1 of the base 105. The side channels C 1 and C2 are
provided for the
purpose of allowing a sled 110 (to be described below) to move forward and
reverse in the
channels CI and C2.
The sled 110 carries the various components making up a supporting assembly of
the
safety stand that is thus movable along the base, and that will raise to
engage the kingpin, thus
allowing the safety stand to accommodate trailers of various lengths. As best
seen in relation to
Figure 10, bearing members illustratively in the form of rollers R are
disposed on each side of
the sled 110 and said rollers are contained within the channels C1 and C2.
Therefore, in use the
rollers cannot jump offof the rails Cl and C2. The sled 110 as best seen in
Figures 8 and 10 will
move on the rollers R in the base 105 until such time as the correct position
for the respective
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2~ s8o ss
trailer being locked is achieved. This position is determined by a sensor 150
provided adjacent
one end of the sled 110, adjacent the support plate 130. This sensor may be a
sonar device to
sense when the nose of the trailer has been reached as the sled moves from a
stored, distal
position away from the dock toward the dock. This use of the sensor allows the
sled to be
positioned substantially in line with the kingpin to enable the support 130 to
move from its
collapsed position to the locking position substantially shown in Figure 6.
The structure and
operation of the supporting assembly, including lifting arms 120, stabilizing
arms 121, a first
drive means such as cylinders 140 and support 130 is substantially the same as
the previous
embodiment (Figs. 1-5), except that they are carried on movable sled 110. The
sensor 150
may be located intermediate the two cylinders 120 and be affixed to a flat bar
116 (as best seen
in Figure 10) positioned to sense the nose of the trailer and thereby position
the safety stand for
each respective trailer length.
Provided near the ends of the pivots for the cylinders 140 are engagement
portions such
as 140e which engage in front of each of the respective flat bar portions 240,
245, 248 or 253
when the safety stand is raised to its locking position as seen in detail A of
Fig. 11. Normally,
the detent of the pivot is retained on the flat bar prior to the cylinders
extending. As the cylinders
140 extend in an upward motion, the detent of the pivot will tend to rest in
the position shown
in detail A of Figure 11. This feature therefore provides locking of the
safety stand in that
particular position along the base 105, using a simple detent of a pivot which
is rotated
downwardly to abut the front of the flat bar as described above. This works in
conjunction with
the forward motion of the support plate 130 from a collapsed position
contained within the sled
to a second position adjacent the kingpin and to a kingpin engaging position
(a third preferred
locking position) wherein the kingpin is engaged by the substantially V-shaped
portion of the
support as best seen in relation to Figure 10 and as was described in regard
to the embodiment
of Figs. 1-5. A surface 131 therefore will engage the kingpin P and tend to
center the kingpin
toward the bottom,of the V at 132. When a constant force is applied against
the kingpin tending
to center the kingpin in relation to the support 130, then a trailer may move
laterally. Once
locked in position by the forward motion of the cylinders 140 and the lifting
arms 120 and
stabilizing arms 121, in combination with the detent of the pivot of the
cylinders 140 engaging
the flat bar portion, then it can be readily seen that the safety stand does
provide excellent locking
benefits.
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21 880 69
The lifting arms as best seen in Figure 8, 10 and 11 are pivoted to the frame
portion 155
of the sled 110 at pivots 120A and 121A respectively and proximate the support
130 at 120B and
121B. It is noted that the positioning of the pivots for the arm 121 are to
the rear and to the
lateral edges of the support plate 130 with respect to the pivots of the
lifting arm 120 to keep the
support horizontal at all times. The lifting arm 120 is engaged with a frame
portion 147 which
are engaged in turn by the rods 141 of the cylinders 140 by pivot pins 148a
and b, to provide a
firm braced supporting structure which will move coincidentally. The lower end
of cylinders 140
are pivoted to sled 110 by pivots 148c and 148d. Also associated with
cylinders 140 is a cover
member 111, attached for movement with the cylinders 140 by support brackets
111 b. The cover
111 keeps out the environment with the stand collapsed.
As best seen in Figure 10, the sled is provided with a second drive means such
as
hydraulic motor assembly M which drives the powered roller R1 which drives the
sled within
the channels C1, C2 of base 105.
The operation of the sled in the base is therefore consistent with the
description in relation
to Figures 1 through 5 in that the support will move firstly with the sled to
be positioned for the
respective trailer being unloaded, for example a 53' trailer, and will once
positioned be powered
to raise from the collapsed position to a second position similarly as
illustrated in Figure 2 and
to a locked position, a position similar to that which is illustrated in
Figure 4. At this position,
a constant pressure is exerted against the kingpin P by cylinders 140. This
constant pressure will
2 0 tend to center the trailer as it is being unloaded and prevent the trailer
from moving away from
the dock.
Therefore, once a tractor positions a trailer in a loading bay, the driver
will winch down
the landing gear supports W to the supporting surface S and subsequently
disconnect the trailer.
The base 105 therefore is positioned in the loading bay and in a plurality of
loading bays
2 5 repetitively as is required by the depot being serviced. Once the driver
leaves with the tractor,
the safety stand is positioned in its locked position by an operator. The
operator commences the
initiation of the unit or this may be done automatically in a conventional
manner. Once the sled
moves in the base to the respective position for the particular trailer that
has been positioned in
the loading bay, the sled will stop (the nose of the trailer having been
sensed by sensor 150) and
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21 680 69
then the supporting assembly will move from its first collapsed position to a
second substantially
vertical position to a third substantially locked position wherein the kingpin
is engaged by the
V-shaped engaging surface 131 of the support 130. The cylinders therefore
provide a constant
force to push back against the kingpin and prevent the trailer from nose-
diving or alternatively
tail diving depending on the structure of the trailer. The present invention
therefore provides a
safety stand that is collapsible and also which locks the trailer in position
and provides a support
adjacent a kingpin and a locking effort against the kingpin for the trailer
regardless of the length
of the trailer.
The sensor 150 which may be any reliable sensor such as sonar, infiared, or
other known
sensors, also includes the necessary electronics to start and stop the
hydraulic motor M to
position the sled in the base. The details of such a sensor and control system
are of conventional
structures and are therefore not described.
Alternatively, a fifth wheel may be used as the support structure with equal
success,
adding the ability to latch the kingpin. Further, a latch mechanism can be
added to the kingpin
engaging mechanism shown in the Figures with equal latching results.
As many changes can be made to the preferred embodiments of the invention
without
departing from the scope thereof; it is considered that all material contained
herein be considered
illustrative of the invention and not in a limiting sense.
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