Note: Descriptions are shown in the official language in which they were submitted.
rrh i s invention rel~tes to trailers.
It is an object of the present invention to provide a
trailer which will at least provide the public wi~h a useful
choice.
Accordingly, the invention consists in a trailer comprising:
(i) A load bearing section;
(ii) A wheel carrying assembly; and
~iii) A draw bar
said load bearing section and said wheel carrying assembly
being displaceable with respect to one another, between a
first position in which said wheel carrying assembly is
operable to support said 102d bearing section for towing in
the conventional manner, and a second position in which said
wheel carrying assembly is operable to support said load
bearing section in a substantially vertical disposition.
To those skilled in the art to which this invention
relates, many changes in construction and widely differing
embodiments and applications of the invention will suggest
themselves without departing from the scope of the invention
as defined in the appended claims. The disclosures and the
descriptiolls herein are purely illustrative and it is not
our intention to limit the scope of the invention by those
clisclosures and descriptions, or otherwise, than by the
terms of the appended claims.
Two preferred forms of the invention will no~7 be described
with reference to the accompanying drawings in which:
Figure 1 shows a side elevational view of a first
embodiment trailer according to the invention in the conventional
position for towing;
Figure Z shows a simi~ar view to figure ] bu~ with thc
load bearing section ~hereof displaced with respect to the
wheel carrying assembly to an alternative position;
Figure 3 shows the ~railer in the configuration depicted
in figure 2 but raised for vertical stowage;
Figure 4 shows a plan view of the wheel carrying
assembly and draw bar incorporated in the trailer depicted
in figures 1 to 4;
Figure 5 shows an elevational view of a second embodiment
of the trailer according to the invention in a conventional
towing position;
Figure 6 shows a similar view to figure 5 but in an
intermediate, partially stowed configuration;
Figure 7 shows a further elevational view of the trailer
depicted in figures 5 and 6 in a fully stowed vertical
configuration;
Figure 8 shows a part sectional plan view of the trailer
depicted in figures 5 to 7 when in the configuration shown
in figure 5;
Figure 9 shows an elevational view of one form of
connection between the draw bar and wheel mounting assembly
of the trailer shown in figures S to 8;
Figure 10 shows a plan cross sectional view of the
attachment shown in figure 9;
Figure 11 shows a view along the line A-A in figure 9;
Figure 12 shows an elevational view of one of the
components of the connection shown in figuTes 9 and 10;
Figure 13 shows an end elevational view of the component
shown in figure 12;
Figure 14 shows an enlarged view 1Ooking alon~ ~he line
B-~ in figure 8; and
Figure 15 shows a view, enlarged to a greater extent,
looking along the line C-C in figure 8.
Referring firstly to figures l to 4 a trailer 10 is
provided comprising a pair of wheels ll mounted on a common
axis 12, a draw bar 13 mounted so that the towing axis is
substantially perpendicular to the axis 12 on which the
wheels ll are mounted, and a load bearing section 14 which
is supported by the wheels ll. The assembly upon which
wheels ll are carried and the load bearing section 14 are
relatively displaceable between a first position shown in
figure l in which the trailer is in the conventional towing
configuration, and a second position shown in figures 2 and
lS 3 in which the wheel carrying assembly can support the load
bearing section in a substantially vertical configuration.
It will be noted that when in the second position the rear
edge 15 of the load bearing section 14 lies substantially
above the rear extremities of the wheels ll when the trailer
is horizontal. The advantage of this is readily apparent
from figure 3 and it will be noted that when the load supporting
section of the trailer has been displaced to the position
depicted in figure 2, the resulting compact combination may
be simply rotated about the wheels ll and stowed readily in
a vertical position, the combination of the wheel carrying
assembly and the edge 15 of ~he load bearing section pToviding
a stable foundation on which the combination may rest. It
will further be noted that the act of displacing the load
bearing section 14 with respect to the wheel carrying assembly
8~
to the position shown in figures 2 and .-, has thc effecl of
retracting the dra~ bar 13 with respect to the load bearin~
section.
In the simplest embodiment of the invention, as shown
in figures l to 4, the load bearing section 14 is simply
slidable with respect to the wheel carryin~ assembly alon~ a
fixed straight axis between the first and second positions.
The form o the load bearing section 14 does not constitute
an essential part of the invention, however it may be in the
form of a one-piece stamping or mouldi.ng produced in metal,
plastics such as for example ABS, fibreglass or any other
suitable material. In ~he form shown however, the load
bearing section comprises a subs~antially planar deck 16
with side boards 17, tow board 18 and ~ail board l9. The
side boards 17, tow board 18 and tail board 19 are preferably
metal pressings and may be pivotally mounted with respect to
the deck and foldable between the positions depicted in the
figures and further positions in which -they lie in planes
substantially parallel to and adjacent the deck 16. It will
be appreciated that when the side boards, tow board and tail
board are in the folded configuration they will yet further
reduce the width of the trailer when in the stowed position
as depicted in figures 3 and 4. As shown catches 20 are
provided to fasten the tow and tail boards to the side
boards when in the erect position.
Referring now to figure 4 the draw bar 13 is as shown,
rigidly fixed to the wheel carrying assembly which preferably
comprises a pair of sub-frames 23. As can further be seen
from figure 4, the rear edge 22 of the draw bar preferably
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extends to a line joining the rear extremities of the wheels
11. It will be apprecia~ed that the tow bar 21 may also be
reducible in length, if~necess~ry or desirable, by making
the same in ~wo sections and having one section telescopic
or foldable with respec~ to the other.
The sub-frames 23 extend from opposite sides of the
draw bar 13 at a position intermediate the ends thereof, but
nearer the end 22. The sub-frames 23 are preferably in the
form of metal pressings, on which suspension units 24 are
mounted which in turn mount the wheels 11 preferably through
conventional dead axles. The suspension units 24 do not
comprise part of the invention, but may, as shown each
comprise a single trailing leaf spring 25 located by a
radius rod 26. Alternatively the wheels could be mounted on
torsional rubber suspension units mounted on the undersides
of the sub-frames 23.
The load bearing section is supported by the chassis
which in turn is defined by the draw bar 13 and the sub-
frames 23 and as stated above is slidable with respect
thereto, between the positions shown in figures 1 and 2.
When the trailer is in the position shown in figure 1 the
centre of gravity of the load bearing section 14 lies just
forward of a ve~tical line through the axis 12 of wheels ll
to provide some downward loading on the tow coupling 28 and
it will be appreciated that this centre of gravity moves
forward as the section 14 is displaced forward to the position
shown in figure 2.
Many different ways of maintainting the load section 14
in engagement with the chassis will present themselves to
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those skilled in ~he art, however, by way of example suitabl~
sectioned members (not shown) provided on the underside of
the load supporting sec~ion 14 may engage in correspondingly
shaped runners 27 mounted on suitable points on ~he tow baT
21 and the sub-frames 23. Suitable catches (not shown) are
also provided ~n the underside of the load supporting section
14 to engage the chassis to lock the load bearing section 14
in the alternative positions as depicted in figures 1 and 2.
The trailer is provided with all the necessary accessories
SUC]l as coupling 28 and lights ~not shown) which are preferably
housed in a bumper which constitutes ~he rear edge 15 to
comply with all the necessary Statutory requirements. These
of course do not constitute part of the invention.
In use, the trailer may be used in the conventional
manner by positiong the load bearing section 14 with respect
to the wheel carrying assembly as shown in figure 1.
When it is desired to stow the trailer in, for example,
a confined space, the load bearing section 14 is slid forward
with respect to the wheel carrying assembly until the position
shown in figure 2 is attained. In this position the trailer
can be simply rotated in an anti-clockwise manner until the
configuration shown in figure 3 is assumed.
Referring now to figures 5 to 14 a further embod;ment
of trailer according to the invention is provided in which
the load bearing section is displaceable with respect to the
wheel carrying assembly to enable the trailer to be securely
supported, for stowage purposes in a substantially vertical
disposition. To this end a trailer 30 is provided comprising
a load bearing section 31; a wheel carrying assembly, generally
designated 32; at least one ~air of wheels 34 mounted for
rotation on the wheel mounting assembly 32 and a draw bar
33. Again relative movemen~ between the loa~ bearing section
31 and the wheel mounting assembly.is pro~ided for hetween a
conventional towing position shown in figure 5 to a vertical
stowed pOSitiOJI shown in figure 7. An intermediate position
is shown in figure 6.
As shown, the load bearing section 31 has a pTessed
metal sheet base 35 which may include longitudinal and/or
lateral stiffening ribs (not shown~ pressed into the surface
thereof. Corner members 26 are provided at each corner of
the base 35 and supported by and between the corner members
36 are side boards 37, a tow board 38 and a tail board 39.
The side boards 37 are preferably fi.xed in position and to.
the base 35 while the tow board 38 and tail board 39 are
preferably removable. The side boards 37, tow board 38 and
the tail board 39 are all preferably sheet metal stampings
or pressings, although it will be appreciated that these
could also be mouldings in plastics OT similar mouldable or
formable material.
It will further be appreciated that the load carrying
section 31 could be formed as a single moulding or pressing
in metal, plastics or fibreglass.
As shown, the wheel carrying assembly includes a cross
member 40 mounted for arcuate movement with respect to the
undersurface of the load hearing section 31 and, in particulaT,
with respect to the base 35. To this end a pair of spaced,
parallel.mounting plates 41 project from the axis of the
cross member 40 adjacent either end thereof, the plates 41
-- 8
pivotall~ engagin~ a pair of brackets 42 (figure 13) extending
from opposed points on ~he undersurface of the base 35,
bolts 43 providing the plvotal attachment. The wheel carrying
assembly further includes a pair of suspension units 44
which, in the form shown, are torsional rubber suspension
units provided as extensions of the cross member 40; a U-
shaped sub-frame 45 extending from the axis of the cross
member 40 and connecting means 46 whereby the draw baT 33 is
pivotally connected to the wheel carrying assembly.
The wheel carrying assembly 32 is preferably constructed
arranged and mounted to allow for displacement of the wheels
between fixed limits. Thus when the wheel mounting assembly
is at the forward most limit, as shown in figure 1, the
wheel axis 47 lies jus~ behind the centre of gravity of the
trailer so that a small downward force exists at the coupling
48. When the wheel assembly is at the rear most limit
however, as shown in figure 7, a plurality of points defined
by the trailer components define a support so that the
trailer may be stowed in a ver~ical position. It will
further be appreciated from viewing figures 5, 6 and 7 that
the act of displacing the wheel carrying assembly between
the opposite limits is effected by raising the draw bar 33
to a vertical position.
As shown, when the wheel caTrying assembly 32 is at the
forward most limit the U-shaped sub-frame 45 ex~ends forward
and upward towards the under surface of the base 35 to
engage the rear end of the draw bar 33. When the wheel
carrying assembly is at the rear most limit the sub-frame 45
extends rearwardly and downwardly. It will be appreciated
that the arcua~e movement between the forward and rearward
limits pivots the wheels out from beneath mudguards 50,
which are mounted on the load bearing section 31.
Referring now to figure 8 it will be noted that the
draw baT 33 engages the CTOSS bar 51 of the U-shaped sub-
frame 44 and is pivotally connected thereto in a manner
which will now be described.
Referring to figures 9 to 12, a circulaT boss 52 is
provided which is mounted on the cross bar 51. To this end
tl~e boss 52 includes an axial slot 53 which is passed over a
flat section 54 (figure 8) provided in the cross bar 51
until the cross bar 51 engages in the central aperture 55 of
the boss. The boss is then clamped in place in the centre
of the cross bar 51 by means of clamping bolt 56. Spaced
about the periphery of the boss and preferably along radii
thereof are a series of bores 57, the purpose of which will
be described hereinafter.
Mounted in the rear end of the draw baT 33 is a pin
mounting block 60, the pin mounting block 60 being retained
in the rear end of the draw bar by means of through bolt~
61. The rear end o the pin mounting block 60 extends out
of the rear end of the draw bar 33 and includes an arcuately
shaped rear surface 62 of a radius corresponding to the
external radius of the boss 52.
Slidable within a through bore 63 in the pin mounting
block 60 is a pin 64. The outer periphery of the pin 64
corresponds substantially to the form of the bores 57 provided
in the boss 52 and indeed the pin 64 is shown engaged in one
of the bores 57 in figures 9 and 10 The pin 64 is connected
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to a tie rod 65 passing centrally through the draw bar and
still furtherJ the pin 64 is biased towards the periphery of
the boss 52 by means of compression coil spring 66 which is
retained within the bore 63 by means Or retaining nut 67.
The boss 52 and the pin retaining bl.ock 60 are maintained
in contact by retaining bracket 70 which is shown on its own
in figures 12 and 13. As can be seen the bracket 70 is
,substantially channel shaped in cross section and includes
an arcuate rear section 71 having inward sides flanges 72
- which engage on either side of the boss 52. The flanges 72
merge into larger side plates 73 which engage cn either side
of the rear o.f the pin mounting block 60. The bracket 70,
after being passed about the boss 52, is engaged with the
rear of the pin mounting block 60 by means of bolts 74
(figure 9) which pass through the cross plate 75 of the
bracket 70 and engage within the pin mounting block 60.
It will thus be appreciated that the connection provided
by the boss 52, the pin mounting block 60 and the bracket 70
enables the draw bar 33 to be pivotally connected to the
wheel carrying assembly yet allows the relative positions of
the draw bar 33 and the wheel carrying assemble to be locked
in various positions.
As can be seen from figures 4 to 6 the draw bar 33 is
engaged with the load bearing section 31 by bracket 80
provided between the point of pivotal engagement with the
wheel carrying assembly and the ,tow coupling 48 and, as
shown, preferably on the forward edge of the load bearing
section 31.
Ref~rring now to figure ~5 the bracket ~0 ~re-ferably
comprises a pair of downwardly extending spaced paralle]
side plates Rl between which is rotatably mounted a roller
~2, the roller 82 being mounted on shaft 83 supported by the
S side plates 81. The bottom edges of the side plates 81
carry inwardly turned flanges 84.
In the form shown the draw bar is a substantially top-
hat shaped me~ber comprising a transverse top plate 85, a
pair of downwardly extending side plates 86 and a outwardly
turned flange 87 extending outwardly from the bottom edge of
each of the side plates 86. It will be seen that the flanges
87 are enclosed within the inwardly turned flanges 84 on the
side plates 81, and thus the combination of the rolle~ 82
and the flanges 84 retains the draw bar 33 within the bracket
lS 80 and ensures engagement of the draw bar with the load
bearing section.
Turning now to figures 5 to 7 it will be noted that the
tie rod 65 attached to locking pin 64 extends forward within
the draw bar 33 to an actuating lever 90 provided adjacent
the tow coupling 48 on the forward edge of the draw bar.
Thus by turning the actuating lever 90 in an anti-clockwise
direction, the pin 64 may be withdrawn from one of the bores
57 provided in the boss 52 and the boss 52 i.s then free to
rotate with respect to the pin mounting block 60 and in turn
the draw bar is free for pivotal movement with Tespect to
the wheel carrying assembly~ Since the draw baT 33 is
maintained in engagement with the load bearing section by
means of bracket 80 by releasing the locking pin 64 and
raising the forward edge of the draw bar the whole wheel
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~ 6 8 ~
carryin~ assembly can be Totated in a counter-c]~ckwi~e
direction since the bracket 80 acts as a fulcrum. The
consequence of this is that the trailer is displaced from
the conventional towing position depicted in figure 5 to a
vertical stowing position shown in figure 7. As can be
seen, the act of moving the trailer from the confi~uration
shown in figure 5 to the configuration shown in figure 7
withdraws the draw bar 33 with respect to the load bearing
section 31 which further reduces the bulk of the trailer in
the stowed configuration.
It will be appreciated that in moving the trailer
between the positions shown in figures 5 and 7 the wheels 33
never actually leave the ground until the very final stage
of movement.
While the locking mechanism to limit movement between
ne wheel carrying assembly and the load carrying structure
is shown and described as being p-rovided between the draw
bar 33 and ~he wheel carrying assemblyS it will be appreciated
that this catch could also be incorporated in, for example,
bracket B0.
Once in the vertical position shown in figure 7 it may
be necessary to manoeuvre the trailer still further and to
this end as shown, we provide a castor wheel 92 on the rear
edge of bracket 70 and further, provide a pair of spaced
castors 93 on the rear surface of the load bearing structure
31. The castors 93 are preferably included in a bumper 94
which further includes light units ~not shown) and a number
plate surround (not shown)to comply with the appropriate
government regulations. ~hus when the trailer is displaced
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~2~686
to a configuration sho~n in fi~ure 7, th~ fo]ded trailer may
be wheeled on the castors to any convenient ]ocation.
Thus ~he invention provides two embodiments of a trailer
which are relatively simple in form, are used in the conventional
manner ye~ which can be readily and easily displaced to an
alternative, more compact configuration for stowage. The
embodiment described wi~h reference to figures 5 to 15
including all its preferred features is considered to have
the following advantages.
1. The act of displacing the trailer from the towing to
the stowing configuration, gives an automatic tipping
function.
2. During the folding or stowing operation the wheel
assembly remains in contact with the ground right until
the final stages of the operation and accordingly only
the weight of the load bearing section and any loads
thereon must be displaced. At the initial stages of
the folding operation the folding moment is the greatest
thus requiring the least effort.
3. The locking pin which locks the position of the wlleel
carrying assembly relative to the load bearing section
self locks and yet is readily releasible.
4. When the trailer is in the stowing configuration it can
be subsequently readily manoeuvred on castoTs 92 and 93.
While the trailer depicted and described takes the form
of a simple box trailer this is by no means an essential
part of the invention and the load bearing section could be
formed ~o any specific purp~se for example boat tTailer,
horse trailer, motor cycle trailer etc.
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