Note: Descriptions are shown in the official language in which they were submitted.
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TITLE
TRAY LOADER APPARATUS
DESCRIPTION
The present invention relates to a tray loader apparatus.
FIELD OF THE INVENTION
The tray loader apparatus of the present invention is
particularly intended for installation in a vehicle to
enable loads to be loaded and unloaded therefrom but it
is to be understood that the apparatus of the present
invention is of general applicability.
SUMMARY OF THE INVENTION
In accordance with one aspect of the present invention
there is provided a tray loader apparatus comprising
rail means having a first rail arranged to be station-
arily fixed to a supporting structure, and a secondrail slidably associated with the first rail and arranged
to move relative to the first rail in a horizontal
direction, a post associated with the second rail and
having a lower end, a load supporting tray mounted at the
lower end of the post and arranged to be horizontally
disposed, in use, and the lower end of the post being
arranged to be raised and lowered together with the tray
relative to the rail means, and the apparatus comprising
means or causing the second rail to move relative to
the first rail so as to extend the rail means in a
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horizontal direction and then causing the lower end of
the post and the tray to be lowered, and for causing the
lower end of the post and the tray to be raised from a
lowered position to its initial position and then for
the second rail to move relative to the first rail so
as to retract the rail means.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will now be described, by way of
example, with reference to the accompanying drawings,
in which:-
Figure 1 is a side elevation of a vehicle having mounted
therein a tray loader apparatus in accordance with the
present invention;
Figure 2 is an end elevation of the apparatus of
Figure l;
Figure 3 is a schematic side elevation of one side of
a tray loader apparatus in accordance with the present
invention in retracted condition;
Figure 4 is a schematic plan view of the side of the tray
loader apparatus shown in Figure 3i
Figure 5 is a view similar to Figure 3, with the tray
loader apparatus in a partially extended condition;
Figu.re 6 is a view similar to Figure 3, with the tray
loader apparatus in.a fully extended condition;
Figure 7 is a perspective elevation of a.first outer
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rail used in the apparatus of Figures 3 to 5;
Figure 8 is a perspective elevation of a second inner
rail used in the apparatus of Figures 3 to 5;
Figure 9 is an upper perspective elevation from a first
side of a traveller used in the apparatus of Figures 3
to 6;
Figure 10 is a lower perspective view from a second side
of the traveller of Figure 9;
Figure 11 is a perspective view of a housing for a post
member of the apparatus of Figures 3 to 5;
Figure 12 is a perspective view of a first post member
arranged to be mounted in the housing of Figure 11.
Figure 13 is a perspective view of a second post member
arranged to be mounted within the post member of Figure
12. ..
Figure 14 is a schematic, perspective view of a post
means 16 in assembled condition.
Figure 15 is a schematic perspective view of a first
latch means arranged to latch alternately the second
rail to the traveller and upon releasing the traveller to
latch the first and second rails together in use;
Figure 16 is an end elevation of a second latch means
viewed from the direction of the arrows of Figure 16
arranged to latch alternately the first post in a
raised position and upon releasing.the first post to latch
the traveller to the second rail.
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Figure 17 is a side elevation of the latch means of
Figure 16 in a first position; and
Figure 18 is a side elevation similar to Figure 17
showing the latch means of Figure 16 in a second
position.
DESCRIPTION_ OF THE INVENTION
In Figures 1 and 2 there is shown a vehicle 10 having
mounted therein a tray loader apparatus 12 in
accordance with the present invention.
The tray loader apparatus 12 comprises a pair of
spaced horizontal rail means 14 to which are mounted
respective vertical post means 16.
The post means 16 have a horizontally disposed tray 18
mounted between them at their lower ends.
IS The apparatus 12 is arranged to operate reversibly
from a first position in which the post means 16 are
retracted, the tray 18 is raised and the rail means 14
are retracted so that the whole apparatus 12 is within
the vehicle 10, to a second position as shown in
Figures 1 and 2 in which the rail means 14 are extended,
the post means 16 are extended and the tray 18 is
lowered.
The construction of the tray loader apparatus 12 is shown
in more detail in Figures 3 to 6.
The apparatus 12 comprises a first, outer rail 20 which
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is arranged to be stationarily, fixedly attached to
the body of the vehicle 10 or another fixed structure.
The outer rail 20 can be seen in detail in Figure 7.
As can be seen in Figure 6, the outer rail 20 is of a
general C-shape in cross-section. The outer rail 20
comprises a rear wall 21, an upper wall 22 and a
depending wall 23 connected to the wall 22. The outer
rail 20 also comprises a lower wall 24 and an upstanding
wall 25 connected to the wall 24. There is an elongated
gap 26 between the walls 23 and 25. A partition 27
extends across the lower part of the C-shape between
the rear wall 22 and the wall 25 so as to define a lower
chamber 28. A stop 27a is mounted on the partition 27.
A roller 29 is mounted in the partition 27 ad~acent one
end of the rail 20. Further, the rear wall 21 is
provided with an aperture 30 at an intermediate location
opposite the gap 26.
The apparatus 12 also comprises a second inner rail 31
which is arranged to be slidably mounted in the rail 20
and to be moved relative thereto. The second rail 31
is shown in detail in Figure 8. As can be seen in
Figure 8, the inner rail 31 is also of a general
C-shape in cross-section. The inner rail 32 comprises
a rear wall 31a, an upper wall 32 and a depending wall
33 connected to the wall 32. The inner rail 32 also
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comprises a lower wall 34 and upstanding wall 35
connected to the wall 34. There is an elongated gap
36 between the walls 33 and 35. The elongated gap 36
is generally aligned in use, with the gap 26 of the
outer rail 20. An upstanding end plate 33a is located
in the gap 36 between the walls 33 and 35 and closes off
the gap 36.
The inner rail 31 comprises at one end in the rear wall
31 an aperture 38. Also, an aperture 38a is located in
the wall 32 and a roller 40a is mounted in the aperture
38a. Further, adjacent the aperture 38, the upstanding
wall 35 is provided with a depending portion in which is
mounted a roller 40.
The roller 40 is supported on the partition 27 and
the roller 40a is supported by the wall 32 and the inner
~ail 31 is supported by the rollers 40 and 40a at one
end and the roller 29 at the other end. The depending
wall 33 of the rail 31 also contains a notch 44 at an
intermediate location. Further a tab 44a depends from the
wall 34 adjacent the roller 40.
A traveller 46, which is shown in Figures 9 and 10, is
arranged to be mounted in the inner rail 31. The
traveller 46 comprises a pair of spaced parallel plates
47 having mounted betweenthem a pair of lower rollers 48
and an upper roller 50. One of the plates 47 contains
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an aperture 47a wh.ilst the other plate contains a
corresponding cut away as can be seen in Figure 10.
When the traveller 46 is moun-ted in the inner rail. 31,
it is rollably supported on the lower wall 34 of the
inner rail 32 by the rollers 48 and.rollably contacts
the lower side of the upper wall 32 of the inner rail
31 through the roller 50.
As can be seen in Figure 9, the traveller 46 also has a
pair of spaced box section projections 52 projecting
outwardly from a side thereof. The projections
52 are arranged to project through the gaps 26 and 36
and to engage with respective, corresponding apertures
54 in a housing member 56 shown in Figure 11 which is
generally channel shaped in cross-section.
The housing member 56 in use provides a support for a
first post member 58 (shown in Figure 12) and a second
post member 60 (shown in Figure 13). The post members
58 and 60 will be described in more detail hereinafter.
Turning back to Figures 3 to 6, it can be seen that the
apparatus 12 also comprises a drive sprocket 62 which is
connected to a drive means such as a motor (not shown).
The apparatus 12 comprises a pair of the drive
sprockets 62 each associated with a respective rail means
14.
Further, the drive.sprockets 62:are interconnected by a
common transverse shaft (not shown) so that they are
commonly operated by the drive means and operate
synchronously.
A pair of sprockets 64 and 66 are rotatably mounted
within the outer rail 20 adjacent the sprocket 62. The
sprocket 64 is located below the partition 27 in the
chamber 28 while the sprocket 66 is located above the
partition 27. A further sprocket 68 is mounted within
the outer rail 20 in the chamber 28 a-t a location remote
from the sprocket 66. The sprockets 64, 66 and 68 are
all rotatably mounted on suitable axles supported by
the walls 21 and 25 of the rail 20.
Further, the sprocket 68 projects upwardly through an
aperture 70 in the partition 27.
A sprocket 72 is mounted between the walls 31a and 35 of
the inner rail 31 at an end which is adjacent the
sprocket 66 in the retracted position of the inner rail
31 shown in Figure 3. Further, the sprocket 72 is
located adjacent an aperture 73 in the wall 34 of the
inner rail 31 and sprocket 72 extends downwardly
partially through the aperture 73. A further pair of
sprockets 74 and 76 are located within the inner rail
31 at the end thereof remote from the sprocket 72. The
sprocket 74 is located between the walls 31a and 35
while the sprocket~76 is located between the walls 31a
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and 33. The sprockets 72, 74 and 76.are all rotatably
mounted on suitable axles supported by the facing walls
of the rail 32.
A further sprocket 78 is mounted between the plates 47
of the traveller 46. A further -large sprocket 80 is
located between the plates 47 of the traveller 46.
As will be described the sprocket 80 is connected to a
further sprocket 82 (see Figure 12) by means of a
common axle as will be described. The common shaft
causes the sprockets 80 and 82 to rotate only simuItan-
eously with one another at all times. An endless chain 83
extends over and engages with all of the sprockets
62, 64, 66, 68, 72, 74, 76, 78 and 80. The chain 83
passes from the sprocket 62, through an aperture in the
wall 2a and an aperture in the partition 27 to the
sprocket 66, then through the inner rail 32 to the
sprocket 80, the sprocket 78, then through the
upper side of the inner rail 32 to the sprocket 76, then
downwardly to the sprocket 74. Subsequently, the chain
83 passes through the lower side of the inner rail
32 to the sprocket 72. The chain 83 passes about the
sprocket 72 and then through the aperture 73 to enter
the outer rail 20 below the wall 34 of the inner rail
31.
The chain 83 then extends to the sprocket:68. The
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chain 83 passes about the sprocket 83 through the
aperture 70 to enter the chamber 28. Then the chain 83
passes to the sprocket 64 and thence through an
aperture in the wall 24 to the sprocket 62.
Further, a latch means 84 shown in Figure 15, is
mounted on a U-shaped plate 86 of the rail 31 adjacent
the aperture 38. The latch means 84 comprises a pin 88
which is mounted in a pair of opposed apertures 90 of
the plate 86. The latch means 84 further comprises a
pair of spaced parallel plates 92 containing aligned
apertures 94. The pin 88 is located within the
apertures 94 to provide a pivot axis for the plates
92.
Further, washers 96 are mounted about the pin 88
between the plates 92 and the U-shaped plate 86.
The plates 92 are spaced apart by rollers 98 and 98a
as can be seen in Figure 15. The roller 98a is mounted
in a lateral projection 100 of the plates 92 at an end
thereof remote from the pin 88.
Spring mean-s (not shown) is provided for urging the
plates 92 toward the apertue 38 so that the projection
100 enters the aperture 38 and the roller 98a is
normally in engagement with the rear wall 21 of the
rail 20. Also the roller 98 is containéd in an
intermediate projection 101 which faces away from the
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projection 100 and is arranged to engage with the apert-
ure 47a o~ the traveller 46. The latch 84 also contains
a projection lOla in the plates 92.
The engagement with the traveller 46 also tends to keep
the plates 92 in engagement with the aperture 38.
A further latch means 102 is shown in Figures 16 to
18.
The latch means 102 is ~ounted to the post 58 as shown
in Figure 12 and comprises a spindle 104 which provides
a pivot axis. A first block 106 is -fixedly mounted
to the spindle 104. A pair of spaced parallel plates
108 are mounted to the block 106 and constitute a first
arm of the latch means 102. A roller 110 is supported on
a spindle at the end of the plates 108 remote from the
block 106. The roller 110 is arranged to engage
releasably with an aperture 112 in the post 58. As
can be seen in Figure 17, the roller 110 engages with the
edge of the aperture 112 in an undercentre position so
that the roller 110 is always tending to be pushed
outwardly by the weight of the post 58.
A second block 114 is also fixedly mounted to the
spindle 104. A pair of spaced parallel plates 116 are
mounted to the block 114 and constitute a second arm of
the latch means 102.. A roller 118 is supported on a
spindle at the end of the plates 116 remote from the
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block 114.
The roller 118 is arranged to engage the underslde of
the wall 33 of the rail 31 as can be seen in Figures 17
and 18.
The arms constituted by the plates 108 and 116 are
disposed at a fixed angle to one another.
In use, the apparatus shown in Figure 3, is caused to
operate by rotation of the sprocket 62 by the drive
means.
The sprocket 62 is caused to rotate in a clockwise
direction ~as seen in Figure 3). This causes the
chain 83 to travel over the sprocket 62. A corresponding
rotation of the sprockets 64, 66 and 68 is established
by rotation of the sprocket 62 as the sprockets 64,
15 66 and 68 are all mounted on the rail 20 which is
held stationary by being mounted to a fixed structure.
However, the sprockets 72, 74 and 76 are mounted on
the inner rail 31. The tension imparted to the
chain 83 causes the rail 31 to extend outwardly of the
20 rail 20 on the rollers 40 and 29. Whilst the rail 31
is moving relative to the rail 20 the sprockets 72,
74 and 76 do not rotate and the chain 83 is simply
maintained in tension.
Thus, in the intermediate position shown in Figure 5,
25 the sprockets 72, 74 and 76 have all moved to the right
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from the position shown in Figure 3 whilst the
sprockets 64, 66 and 68 have remained stationary. As
the rail 31 moves relative to the rail 20 the projection
100 of the latch 84 is spring urged into engagement
with the aperture 38 such that the roller 98a is in
rolling engagement with the rear wall 21 of the rail
20.
The movement of the rail 31 continues until the roller
tab 44a strikes the stop 27a. At this point the
roller 98a and projection 100 are urged into engagement
with the aperture 30. Simultaneously, the roller 98
of the latch 84 is withdrawn from the aperture 47a
of the traveller 46. This effectively latches the
rails 20 and 31 together and prevents any further
relative movement of these components whilst simultane-
ously unlatching the traveller 46 from the rail 31 and
allowing the traveller 46 to move relative to the
rail 31.
At this polnt the sprockets 72, 74 and 76 commence to
rotate and drive is transmitted to the traveller 46
within the inner rail 31 via the sprockets 78 and
80 which do not rotate.
The traveller 46 moves relative to the rails 20 and 31
to the right as seen in Figure 3 on the rollers 48
and 50. Whilst the traveller 46 is moving relative
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to the rails 20 and 31 the sprockets 78 and 80 do not
rotate and the chain 83 is simply maintained in tension.
Further, the roller 118 of the latch 102 bears against
the underside of the wall 33 of the rail 20 while the
weight of the post 58 bears down on the roller 110.
However, at a certain point in movement of the traveller
46, the roller 118 engages the aperture 44 in the rail
20. This enables the weight of the post 58 to
act downwardly on the roller 110. As can be seen in
Figures 17 and 18 the upper and lower edges of the
aperture 112 are cut at an angle such that the edges
of the aperture 112 taper inwardly of the wall of the
post 58. The rail 31 continues moving unt.il it reaches
a position where the rearward end of the notch 44 is
in engagement with the roller 118 as shown in Flgure 18.
Thus, engagement with the aperture 44 causes the roller
110 to be pivoted outwardly of the post 58 by the weight
of the post 58 acting downwardly, to the position shown
in Figure 18.
Further, at this point the leading projection 52 of the
traveller 46 engages with the plate 33 in the rail 31
to prevent further movement of the traveller relative
to the rail 31. Thus, the sprockets 78 and 80 are then
caused to rotate by the chain 83.
Rotation of the sprocket 80 causes similtaneous rotation
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of the sprocket 82 which is mounted on a common shaft
as described above.
The sprocket 82 is operatively connected to a chain 120
shown in Figure 12. The chain 120 has a first end
mounted to a bracket 121 at a lower end of the post
58 and a second end mounted to a bracket 122 at an
upper end of the post 58.
Further, in addition to the sprocket 82, the chain 120
passes over an idler sprocket 123.
lQ Once the roller 110 has been disengaged from the
aperture 112, the post 58 can drop under the lnfluence
of gravity.
Further, the chain 120 is caused to pass over the
sprockets 82 and 123 by the rotation thereof caused
by the sprocket 80. Thus, the post 58 descends in a
controlled manner from the housing 56. As shown in
Figures 12 and 14 the housing 56 also contains guide
rollers 110a and 110b for the post 58. These rollers 110a
and 110b are mounted in the housing for rotation and
rollably contact the post 58.
The roller 113 also rollably contacts the outer face of
the post 58 as the latter descends as shown in Figure 18.
Also, the post 60 which is mounted within the post 58
is also caused to descend. This is because the post
60 is suspencled from a chain 130 which has one end
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anchored to an aperture 13b (see Figure 9) in a
projection 52 of the travel]er 46 by means of a pin 132
and the other end attached to an upper end of the post
60. The chain 130 also passes over an idLer sprocket
133 located in the upper end of the post 60 by means of
an axle located in a pair of opposed apertures 133a
(one of which can be seen in Figure 12). As the post
58 descends the post 60 also descends within the post
58 such that the post 60 descends more rapidly and
contacts the ground prior to the post 58 reaching the
lower end of its travel.
The lower end of the post 60 is provided with a bracket
136. The bracket 136 contains a spindle 138 to which
the tray 18 is pivotally connected. The pivotal
connection means that as the tray 18 approaches the
ground it can simply pivot upwardly if it encounters
any obstruction.
Downward movement of the post 58 is not affected by
contact of the tray 18 with the ground, but simply
continues until the bracket 122 contacts the roller
llOa.
When it is desired to raise the tray 18 from ground level,
the sprocket 62 is simply caused to rotate in the
anti-clockwise direction as seen in Figure 3. This
causes the chain 83 to travelin the same direction
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and the sprockets 64r 66, 68, 72, 74, 76, 78 and 80
to be rotated as seen in Figure 3. This causes the sprocket
82 to be rotated in the same direction as the sprocket
80. Thus, the chain 120 passes over the sprockets 82 and
123 and lifts the post 58 which causes lifting of the
post 60 at a more rapid rate.
Thus, the tray 18 is lifted along with the posts 58
and 60 until the post 60 is fully retracted in the
post 58.
The roller llOb also acts as a stop by contacting a
roller 134 which is mounted to the post 58 and is
arranged to engage with the housing 56 to provide
additional guidance for the post 58. This action
causes upward movement of the post 58 to be arrested
and.retractive movement of the travelle~ 46 to be
commenced by cessation of rotation of the sprockets
78 and 80 and 82.
As shown in Figure 18, the roller 118 is located in
the notch 44 in an undercentre mannex and the adjacent
edge of the notch 44 is sloped. Thus, once the
roller 110 is opposite the aperture 112 and upward
motion of the post 60 is arrested. The roller 118 is
pushed out of the aperture 44 along the.sloped left
hand side thereof as seen in Figures 17 and 18. In
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this way, the post 58 is latched in its uppermost
position while the traveller 46 commences travel to the
left as seen in Figure 3.
This movement of the traveller 46 is continued until
it is stopped by engagement with the projection lOla
of the latch 84. This action causes the projection 101
to engage with the aperture 47aof the traveller 46 and
to latch the traveller 46 to the rail 31 and simultane-
ously to disengage the projection 101 from the aperture
30. This enables the rail 31 to move relative to the
rail 20. It should be noted that the latch 84 is an
overcentre latch when latching the rails 20 and 31
together and a positive action as described is required
to disengage it from the aperture 30.
This cessation of movement of the trave}ler 46 causes
the sprockets 72, 74 and 76 to cease rotation and
the rail 31 to commence retractive movement caused by
rotation of the sprockets 64, 66 and 68. The retractive
movement of the rail 32 continues until an end 31a
(see Figure 15) of the inner rail 31 contacts a spacer
mounted on the axle of the sprocket 66.
In all phases of operation of the apparatus 12 the
tray 18 remains substantially horizontal unless, as
mentioned above, the tray 18 contacts an obstruction
which causes it to pivot on its mountings to the posts
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60.
As can be seen in Figure 14, the tray 18 conveniently
comprises a box section member 150 on either side of the
tray 18. Each box section member 150 fits in a respect-
ive bracket 136 and is pivotally secured by the pin
138. Further, a corrugated plate 152 is mounted between
the members 150. A wheel 154 is mounted to each member
150. Each wheel 154 projects through an aperture in the
plate 154 to act as a ground engaging member when the
tray 18 is lowered.
Modifications and variations such as would be apparent to
a skilled addressee are deemed within the scope of the
present invention. For example, the single flexible drive
means in the form of the chain 83 and its associated
sprockets could be replaced by any e~uivalent means such
as an endless toothed belt arranged to engage with rollers
containing recesses of complementary shape to the teeth of
the belt. For example,the posts 60 may be omitted and the
tray 18 may be attached to an elongated post 58 although
the telescoping arrangement of the posts 58 and 60 does
enable a substantial degree of drop to be obtained in an
environment with a low headroom.
Further, more than one post 58 may be used on each side for
a multiple point lift. Also, the rails 20 and 31 need not
be nested as shown in the drawings but simply associated
with one another.
