Note: Descriptions are shown in the official language in which they were submitted.
2~ 3~i4
The ~resent invention relates to devices Eor the
disposition of ladders and more specifically to a device
for the transportation, raisinq and lowerinq of a ladder.
Prior art devices Eor the disposition of ladders
qenerally ~rovide either for the upriqht mountinq of a
ladder on a trolley or for sup~ortinq a ladder in a
horizontal position for transport, with means ~rovided for
deployina a ladder into a vertically upriqht position, and
thereafter su~orting the ladder by various systems
employinq struts, braces and similar mechanisms. ~lthouqh
some prior art devices for the disposition of ladders
provide for the pivoting of ladders once about a single
fulcrum on a support frame, such devices commonly either
emDloy a winch to effect that ~ivotina or necessitate that
the support frame have a hiqh ~rofile to ~rovide adequate
support to the lower end of the ladder.
The above-described disadvan-taqes of prior art
for the dis~osition of ladders may be reduced by orovidinq
a device for the two stage rotational disposition of
ladders about two se~arate Eulcrums.
Accordingly, the present invention provides a
machine for supporting a ladder. The machine com~rises a
frame having front leq means at the ~roximal end thereoE,
rear leg means and ladder fixinq means at the distal end
thereof and cradle fixina means between the proximal end
thereof and distal end thereof. A cradle is also included
having means -Eor rotatable attachmen-t to op~osite sides of
said proximal end of said frame. ~ongitudinal cradlina
means are disposed between said means for rotatable
attachment of said cradle and the distal end of said
cradle and have means for rotatable attachment of a ladder
therebetween near said distal end of said cr~dle.
In drawings which illustrate embodiments of the
invention,
Fiqure 1 is an exploded ~erspective view of one
embodiment of the machine oE the present invention,
Fiqures 2 throuqh 4 are, respectively, detailed
top, side and end views of the cradle shown in the
`7~
embodiment of the invention depicted in Fiqure 1,
Fiqure 5 is a side view of an emhodiment of the
Erame of the ~resent invention,
Fiqure 6 is a detailed cross-sectional view
taken alonq the Line B-B' in Fiqure 5,
Fiqure 7 is a detailed side view the up~er
portion of the o~oosite side of the Erame shown in Fiqure
5,
Fiqure 8 is a detailed cross-sectional view of
the embodiment shown in Fiqure 7, taken about the line A-
A', and
Figure 9 is a detailed cross-sec-tional view of a
latching mechanism present in an embodiment o~ the
invention.
Referrinq to Eiqure 1, lon~itudinal su~ort
means 5 and 6 of frame 100 may join front le~ means 110 to
rear leq means 120. Frame 100 may further include
transverse su~ort means 7 and 25 between opposite sides
of frame 100. The rotatable attachment of cradle 200 to
frame 100 may be near the top of the ~roximal end of the
frame 100.
Ladder fixinq means 8 at the distal end of frame
100 may comprise a C-sha~ed bracket between the opposite
sides, for example between the rear leg means l20, and
openinq towards the proximal end oE Erame 100 and ~urposed
to en~age a ladder. Such a C-shaped bracke-t may, for
example, include one or more lockinq floor ~ads 19 on the
base thereof. In the alternative thereto, or in addition
thereto, the C-sha~ed bracket may be pur~osed, for example
by means of a floor piece ]40 ~urposed to maintain the
bottom of a ladder above the surface on which other parts
of the frame 100 rest. In the alternati~e to such a C-
shaped bracket the ladder fixinq means 8 may comPriSe
known latchinq means purposed to enqaqe a ladder.
Either or both oE front leq means 110 and rear
leq means 120 may have lockable wheels, such as rigid
casters 17 or swivel casters 18, at the base thereof, such
wheels may, for e~ample, be three or four in number. If
the number oE such wheels is three they may, for example,
be arranged such that two of such three lockable wheels
are at the proximal end of the base and one oE three such
lockable wheels is at the distal end of the base.
The frame 100 may further comorise stabili~ina
arms 9 capable of engaqing the surface on which other
parts of the frame 100 may be restinq. Such stabilizinq
arms 9 may be rotatably attached to the frame 100 and may,
for example, be capable of rotating outwardly and
downwardly to enqage the surface and upwardly and inwardly
to enqaqe the frame 100. Such stabilizing arms 9 may
comprise a fin 150, ~ro~ectinq from the proximal end of a
central member 160, and a Eoot pad 170 at the distal end
of the central member 1~0.
The frame 100 may Eurther comprise locking means
16 capable of releasably enqaqing such stabili~inq arms 9
proximally to the fin 150 and the ~roximal end of the
central member 160. Each such lockinq means 16 may, for
example, com~rise a Plate rotatably enqaqin~ the outer
surface of front leg means llO and adjustable in heiqht
therealonq by means of for example, a thumbscrew toqether
with a clasP encirclinq the corresPonding front leg means
110 and a-ttached to such a plate.
The cradle 200 may include su~port brackets ~1
between longitudinal cradlinq means 130 and the proximal
end of the cradle 200, which may also include means for
raising a ladder to provide sufficient clearance from the
surface on which other parts of the Erame 100 are restinq,
so that upon a ladder beinq rotatably attached to the
distal end of the cradle 200 and the cradle 200 beinq
rotated, contact oE an end of that ladder wi-th the surface
on which the frame 100 is restinq does not impede the
cradle fixing means from engaqinq. Such means for raisinq
the ladder to provide sufficient clearance may, for
example, comprise a lever 23 rotatably attached to the
proximal end of the cradle 200 and purposed to enqage a
ladder runq.
The cradle 200 may further comPrise means for
slowly lowering the cradle 200. Such means may comprise a
shock absorber 14 and means, such as for example, a
bracket 13 near the top of the proximal end oE the frame
100 and a slat 3 extending downwardly from the proximal
end of the cradle 200, the slat 3 having therethrough a
hole for the insertion of a pin (not shown) through the
slat 3 and through the shock absorber 14.
The cradle fixing means may comprise a
latch/lever 12, a latch spring 2, a lever/safety pin 3, a
safety pin plate 11 and latch spring positioning blocks
20. The elements of such cradle fixing means are arranged
as follows. When the cradle fixing means is not engaged
the latch spring 2 projects below the latch/lever 12. ~s
the cradle 200 is raised upwardly and forwardly the latch
spring 2 climbs onto and over a tapered surface of
latch/lever 12. (Such tapered surface would present an
upwardly and outwardly projecting surface). The latch 12
then engages a non-tapered portion of latch/lever 12.
Turning latch/lever 12 through 1~0 enables reversal of
the orientation of the tapered surface and hence permits
the latch spring 2 to climb onto and down the tapered
surface and hence permits the cradle 200 (and thereby a
ladder therein) to be lowere~d.
The means for rotatable attachment oE a ladder
may comprise, for example, a guide 300 having longitudinal
guide means 4A and 4B and, between opposite sides of said
guide 300, transverse guide means 4C, the transverse guide
means 4C including means, such as for example~ clamps or
sets of nuts and bolts, for attaching a ladder to the
guide 300. Such means 4C may also include, for example,
plates attachable to guide means 4~ and 4B specially
adapted to engage ladders of various cross-sections.
The frame 100 may further comprise storage means
15 attached, for example, to the underside of longitudinal
support means 5 and 6 and to rear leg means 120 as shown
in Figure 5.
In use, an ordinary or extendable ladder may be
releasably attached to the cradle 200 or guide 300. If
J~
the ladder is attached directly to the cradle 200 such
attachment may be by means of clamps or of sets o~ nuts
and bolts that permit rotation of the ladder about the
distal end of the cradle 200. In the alternative, the
ladder may be attached to the guide 300 by means of, for
example, clamps or sets oE nu-ts and bolts, the guide 300
havinq been rotatably mounted near the distal end of the
cradle 200. ~ith its lonqitudinal axis substantially
parallel to and sliqhtly above the up~er surEaces of the
cradle, the ladder may be placed in the guide with the
upper and lower ends of the ladder extending past the
proximal and distal ends of the cradle 200 and frame 100.
The proximal end of the ladder may then be pushed downward
until the cradle fixing means enqages. The distal end of
the ladder may then be pushed downward until the distal
end of the ladder is enqaqed by ladder fixinq means 8.
~ter -the cradle 200 has been rotated about its rotatable
attachment to the frame 100, the distal end of -the ladder
or, if the guide 300 is present, both the distal end of
the guide 300 and the distal end of the ladder, may be
rotated rearwardly and downwardly to be enqaqed by ladder
engaqing means 8~ ~he distance between lonqitudinal
cradling means 130 may, for example, be less than the
distance between lonqitudinal support means 5 and 6.
~5 It will be obvious to those skilled in the art
that the scope of the present invention is not restricted
to the embodiments disclosed above, but may instead be
varied within the scove of the followinq claims without
departing from the spirit and sco~e of the invention. For
example, the embodiments described above may be operated
wholly or partly by hydraulics or may be adapted to
outdoor use by being equipped with larger wheels and/or a
larger wheelbase than would be used for indoor use. It
will also now be obvious that the above-described
embodiments may be enlarqed and/or strenqthened to enable
them to be used to erect a free standinq surface such as a
ladder or a platform.
