Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
"~ETRACTABLE LANDING GEAR FOR TRAILERS"
BACKGROUND OF THE INVENTION
This invention relates to new and useful improve-
ments in commercial trailers and the like normally pulled by
a cab unit and connected to the cab unit by means of a fifth
wheel assembly.
Conventionally, a second trailer is often connected
to the ~irst trailer and ball hitches or the like are usually
utilized to connect the two trailers together with of course
the necessary safety equipment and means to connect the brake
system of the cab to both of the trailersO
This conventional system of connecting one trailer
to another suffers from several disadvantages. Firstly it is
difficult to back up the two trailers when it is understood
1 15 that the first trailer itself is connected to a cab unit.
Secondly the conventional connection often results in sway
occurring between the second and first trailers and if this is
not controlled, it can be extremely dangerous to the point
where such combination units may sway out of control.
Another disadvantage with the conventional connection
is that when the second trailer is removed, the hitch assembly
normally extends rearwardly of the first trailer thus making it
difficult to back this trailer up to a dock and to be positioned
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with the rear edge of the trailer contiguous with the front
edge of the dock.
SUMMAR~ OF THE INVENTION
The present invention overcomes these disadvantages
and in accordance with the invention there is provided in a
trailer assembly which includes a front trailer and a selec-
`' tively attachable rear trailerl said front trailer including
a pair of spaced and parallel longitudinally extending chas-
sis members; the improvement characterized by a landing gear
assembly situated at the rear of said front trailer, means
mounting said landing gear assembly to said front trailer
for movement between a position underneath said ~ront trail-
er and to a position extending behind said front trailer and
vice versa, ground engaging wheels supporting said landing
gear assembly, said landing gear assembly including a front
portion underneath said front trailer and a convertor por-
tion behind said front portion and means on said convertor
po.rtion for detachably securing the second trailer thereto
and means to detachably s~cure said landing gear assembly
in either of said two positions; and a transverse hi.nge me-
ans between said front portion and said convertor portion
whereby said convertor portion is pivotally connected to
said front portion for movement in a vertical plane.
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Another aspect of the invention is to provide a
device which reduces the tendency of the second trailer
to sway relative to the first trailer.
A still further aspect of the invention is to provide
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a landing gear assembly for connecting two trailers together
in which the landing gear assembly can be completely retrac-
ted when the second trailer is connected.
With the foregoing in view, and other advantayes as
will become apparent to those skilled in the art to which this
invention relates as this specification proceeds, my invention
consists essentially in the arrangement and construction of
par~s all as hereinafter more particularly described, reference
being had to the accompanying drawings in which:
DESCRIPTION OF THE DRAWINGS
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Figure 1 is a fragmentary isometric view of the as-
sembly connected to a front trailer shown schematically, and
being situated in the extended position.
Figure 2 is a view similar to Figure 1 but showing
the landing gear assembly in the fully xetracted position.
Figure 3 is an enlarged cross sectional view showing
one method of mounting the landing gear assembly to the chassis
members of the front trailerO
Figure 4 is a side elevation reduced in scale from
the rest of the drawings, showing two trailers connected toyether
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by the present invention.
Figure 5 is a vi.ew similar to Figure 4 bu-t showing
the second trailer removed and the landing gear assembly fully
retracted under the rear of the first trailer.
In the drawings like characters of reference indicate
correspondins parts in the different figures.
DE~AILED DESCRI1?TION
Proceeding thereore to describe the invention in de-
tail, re~erence should first ~e made to Figures 1 and 2 in which
10 illustrates generally, a front trailer shown schematically
and including a pair of spaced and parallel longitudinally ex-
tending chassis members 11 with a trailer floor 12 supported
thereon and the body enclosure 13 being illustrated in fragmen-
tary fashion.
The front end 14 of the front trailer 10 is adapted to
be mounted upon a cab unit (not illustrated) by means of a con-
ventional fifth wheel attachment ~not illustrated).
The rear of the front trailer 10 is supported upon a
landing gear assembly collectively designated 15. This landing
2Q gear assembly includes a front portion collectively designated
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16 and a convertor portion collectively designated 17. Deal- :
ing first with the convertor portion 17 r it includes a pair
of spaced and parallel frame members 18 supported in the de-
sired position b~ rear transverse structure 19 extending be-
tween the xear ends through the vertical members 20. A plat-
form 21 extends between adjacent the rear ends of the frame
members 18 and a conventional fifth wheel plate assembly 22
i5 supported upon this platform 21.
A pair of plates 23 are mounted on the front ends of
the ~rame members 18 and pivot pins 24 extending through
rubberized bushings 25, connec~. these plates 23 to transverse
bearing members 23A extending from the rear of the front portion
16 thus mounting the convertor portion 17 to the front portion
16 for pivotal movement in a vertical plane around the axes of
the pins 24.
It will noted that this mounting also prevents any
side to side mo~ement of the convertor portion relative to the
front portion 16 thus assisting in preventing side sway from
occurrlng .
The front portion 16 consists of a pair of spaced and
parallel channel frame members 26 shown specifically in Figure
2, braced by means of a cross member 27 and engaged under the
longitudinally extending chassis members 11 of the front trailer.
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These longitudinal chassis members are preferably in the form
of eye beams with a horizontal lower flange 28 which rests
within the channel members 26, the open sides of which face
upwardly as clearly illustrated.
S It is desirable that roller means be provided between
the channel members 26 and ~he chassis memhers 11 and one form
oE such roller means is illustrated in Figure 3.
Pairs of brackets 29 extend downwardly from each side
flange 30A of the channel members 26 and a horizontally situated
; 10 roller 30 is journalled between the brackets 29, upon a mounting
pin 31 extending between the bracket members. The roller ex-
tends upwardly through a cut out portion 32 in the base of the
channel members 26 so that the horizontal flange 28 of the
chassis members 11 engages upon these rollers. The channel mem-
bers maintain the front trailer unit within the channels so that
the landing gear assembly 15 can move from the extended position
shown in Figure 1, to the retracted position shown in Figure 2
and vise versa.
Means are provided to restrain the landing gear assem-
bly in either of the two positions, said means taking the form of
a latch plate 33 secured to each of the channel members 25 adja~
cent the front ends 34 thereof. It should be observed that only
one of the latch plates 33 is shown in the accompanying drawings.
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These latch plates include the rearwaxdly facin~
hook portions 35 which engage projecting pins or studs 36 ex-
tending from a reinforcing plate 37 welded to the innex flange
of the longitudinal chassis members 11. Locating pins 37 ex-
tend from plates 38 welded to the vertical flanye of ~he chas-
sis members 11 and prevent relative vertical movement betw~en
the front trailer unit and the landing gear assembly 15.
It should be observed that a pair of ground engaging
wheels collectively designated 39 mount the convextor portion
17, said whee~ assemblies being conventional and having brakes
~not illustrated) connected thereto.
Two pairs of ground engaging wheel assemblies 40 and
41 are secured to the front portion 16 o~ the landing gear as-
sembly 15 adjacent the rear ends of the ~ro~t portion 16,
These are mounted upon springs 42 in the usual way and also in-
clude conventional brakes~ All of the brake assemblies are of
course operatively connected to the cab assembly in the usual
way. However as such details are conventional, it is not be-
lieved necessary to describe same further~
2a When in the ully rekracted position, the pins 37'
may be removed from the apertures within the plates 38 and re- ;
inserted through apertures formed in further plates 43 secured
to the vertical flange of the chassis members just rearwardly
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of the plates 37'. The latch hooks 33 engage these pins when
the landing gear assembly is in the fully retracted position
shown in Figure 2.
When in the retracted position, it will be noted that
the fifth wheel plate 22 engages under the floor 12 of the front
trailer and between the longitudinal chassis members 11 thereof
so that it is completely retracted thus leaving the rear end of
the front trailer clear to enable it to be backed up to the
front edge of a conventional landing dock.
In operation, and assuming that the landing gear as--
sembly is in the retracted position shown in Figure 2, the pins
37' are removed from the latch hooks 33 and the apertures within
plates 43. By chalking the wheels of the landing gear assembly,
the front trailer together with the cab unit are driven forward
thus extending the landing gear assembly to the position shown
in Figure 1.
The second trailer 44 (shown schematically in Figures
plate
4 and 5) is then engaged over the fifth wheel/22 in the usual
manner and locked into position whereupon the double unit can
be driv n and operated by the cab unit.
:~ When it is desired to remove the second trailer 44,
the front is jacked up in the conventional manner and disconnect-
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ed from the fifth wheel plate 22 whereupon the wheels of the
landing gear assembly may be chalked, and the fron~ trailer
moved slowly rearwardly until the landing gear assembly is
fully retracted as shown in Figure 2 whereupon pins 37' may
be inser~ed within plates 43 so that they are engaged by the
latch plates 33.
Finally it should be noted that as the frame members
18 pass under the rear end of the first trailer, transverse
rollers 44~mounted at the rear end of the longitudinal chassis
10 members 11, engage the upper suxfaces 18A of the members 18
prevent any binding from occurring as these members pass under
the chassis members during retraction and extension thereof.
It will therefore be seen that the landing gear assem-
bly cannot only be retracted and extended as desired but also
15 gives adequate nonswaying suppoxt to the front trailer when used
alone and to the rear trailer when extended as shown in Figure 4.
Finally it should be noted that additiona]. hook plate
33A may be secured to the side of the channel members 16 with
an additional pin 36A extending from the frame member 11. This
20 gives additional support when the device is extended as in
Figure 1
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~ince various modifications can be made in my inven-
tion as hereinabove described, ancl many apparently widely dif-
ferent embodiments of same made within the spirit and scope
of the claims without departing from such spirit and scope,
it is intended that all matter contained in the accompanying
: specification shall be interpreted as illustrative only and
not in a limiting sense.
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