Note: Descriptions are shown in the official language in which they were submitted.
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APPARATUS FOR LIFTING OBJECTS HAVING A HOLLOW
CYLINDRICAL CORE WITH REMOTE POWER-ACTUATED RELEASE
Technical Field
The invention relates to devices for lifting, moving and h~ntlling paper
rolls and similar massive articles having a central hollow cylindrical core, and more
particularly to a lifting probe having a remote, power-~ctll~ted release.
Background Art
N~wsp~ and similar materials are transported in large, massive rolls in
which the sheet material is wound around a central cylindrical core of fibre or cardboard.
Such objects are sufficiently heavy that they must be handled by crane for loading and
unloading from vessels. They are readily damaged and so must be handled carefully in
such loading and unloading. To facilitate loading and unloading such rolls, various core
lifting chucks have been developed which have a probe which is inserted into the central
cylindrical core of the roll and which grips the central core, to allow the roll to be lifted
by a cable from a crane or the like.
The present inventor's United States patent no. 5,439,264 issued August
8, 1995, entitled "Apparatus for Lifting Objects Having a Hollow Cylindrical Core"
discloses a compact lifting probe which uses a single lifting cable attached to scissoring
toggle arms, which can be readily removed from the roll core in case of j~mming, is
readily adjustable, and which is self-releasing when the load is to be released. It has a
lower probe section which is inserted into the hollow core of the paper roll consisting of
an inner component which is attached to a single lifting cable by means of the toggle
arms, and an outer component which is attached to a horizontal plate against which the
toggle arms act. When raised, the outer component is pressed dow--w~ldly. This causes
a cone-shaped lower end of the inner component to force ~u~waldly the ends of a number
of pivoting fingers on the lower end of the outer component, which then engage and grip
the inner core of the paper roll. When the roll is returned to the ground, the inner
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component drops back down, the fingers retract and the probe is removed from the core.
Prior designs required two cables and two widely separated lifting arms, and so were
cumbersome, heavy and unwieldy to operate, taking two persons to handle. The width
of the two arms, which frequently swing around during the loading process, caused
5 safety problems, and the two lines may become tangled.
One aspect of the present inventor's prior lifting probe is that it
automatically releases from the core of the paper roll as soon as the roll is placed on a
surface and the lifting pressure from the cable is released. In some situations that can
be undesirable, since some adjustment or juggling of the paper rolls may be required by
10 the crane operator after the roll has first been placed on a surface. It is preferable that
the release of the probe can be made remotely at the discretion of the operator to avoid
the danger of a worker in close proximity to the cable, lifting probe and paper roll.
There is therefore a need for a lifting probe which can be released remotely from the
paper roll.
Disclosure of Invention
The invention provides an apparatus for lifting objects having a vertically
oriented, hollow cylindrical core, the appal~lus of the type comprising a) means for
20 connf~cting a hook or other lifting device; b) a face plate provided with a horizontal
aperture; c) linkage means connecting the hook-connecting means to the face plate; d)
a hollow sleeve dimensioned to be inserted into the core and comprising at the lower end
thereof a plurality of jaw segments forming a diametrically expandable lower end; e) a
transverse flange attached to the end of said sleeve having a diameter greater than that
25 of the core; f) a latch assembly attached to the transverse flange and provided with a
horizontally extending bolt biased to extend into the aperture in the face plate and handle
means for releasably retracting the bolt means; h) a rod extending through the sleeve and
having at the lower end thereof an ouLwa~lly tapered end; and i) spring means biasing
the rod dowllwardly in the sleeve; wherein a power-actuated hydraulic or air cylinder is
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provided to secure the horizontally extending bolt in the core-eng~ging orientation until
remotely released by the lift operator.
Brief Description of Drawin~s
In drawings which illustrate a plere..~d embodiment of the invention:
Fig. 1 is a perspective view from above of the probe of the invention;
Fig. 2 is an elevation view, partly in cross section along line A-A of Fig.
2, of the probe of the invention with the toggle arms in raised position;
Fig. 3 is a front view of the latch portion of the probe illustrating the
automatic release cylinder;
Fig. 4 is a front view of the latch portion shown in Fig. 3;
Fig. 5 is an exploded view, partly in cross section of the latch portion
shown in Fig. 3; and
Fig. 6 is a perspective view from above of an adapter sleeve for use with
the probe of the invention.
Best Mode(s) For Carryin~ Out the Invention
With reference to the drawings, the lifting device of the invention is
designated generally as 40. It has a horseshoe shaped plate 1 which is provided with hole
42 through which a hook or cable is inserted to lift the device. Two pairs of link plates
3 are pivotally attached to each arm of plate 1 by capscrew and nyloc nut assemblies 2.
Toggle arms 10 are pivotally attached at one end thereof between each pair of link plates
3 and at the other end thereof between toggle assembly plates 9. Toggle assembly plates
9 are welded to threaded block 6 to which are also welded toggle stops 7 which limit the
upward movement of the toggle arms 10. A latch assembly, described in further detail
below, is mounted in the front of toggle assembly plate 9, and plate 9 is provided with
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hole 8 to receive the latch plunger 25 (Fig. 4) when the toggle arms are in the lowered
position.
Forming the lower part of the device is a circular plate 12 provided with
a central aperture in which is welded a hollow cylindrical sleeve 13. Expanding segments
20 are held by a segment holder 17 which is threaded into the lower end of sleeve 13.
There will generally be four of the segments 20, which pivot oulwafdly on pin 18 and
are provided with two l/4-inch rubber O-rings 44 in slots 46 which bias the segments
inwardly and assist in the gripping function of the segments. Conical mandrel 21 is fixed
to threaded block 48 which receives threaded drawbolt or "redi-rod" 14 which will
10 typically be l-inch diameter. An angle C for the mandrel 21 of 19 degrees has been
found to be optimal. Drawbolt 14 is locked into block 48 by locking pin 16. A spring 15
is provided around the drawbolt 14 between shoulder 50 of block 48 and annular spacer
52 which is welded to the interior of sleeve 13. The upper end of drawbolt 14 passes
through sleeve 11 and is threaded into threaded block 6. A lock pin 5 extends through
15 slots 33 in either side of block 6 and through a slot in drawbolt 14 to prevent it from
turning once it is in place. Nyloc nut 4 seals the upper end of the block 6. The typical
length of the probe portion of the device (parts 13, 17, 20) is 16 inches, and the
maximum width of the mechanism is about 33 inches.
Looking at Figures 3 through 5, latch assembly 78 consists of latch handle
20 23 (shown with a spherical end in Fig. 3 through 5), hollow cylindrical latch barrel 24,
latch plunger 25 and latch cap 22 (shown as a hex nut in Fig. 3 through 5). The
threaded end 61 of handle 23 is threaded into threaded hole 63 in latch plunger 25,
shown in cross-section in Fig. 5. A spring 54 is provided within latch barrel 24 between
cap 22 and cavity 65 of plunger 25 (shown in dotted outline in Fig. 5) to bias the plunger
25 to the left in Fig. 4 and 5. Latch plunger 25 has a tapered end 29 and a notch 67. Latch
barrel 24 has a slot 30 through which latch handle 23 extends, with notch 31. Latch
barrel 24 is welded to a mounting plate 27 which is in turn welded to the top of circular
plate 12. Trigger 26 is a horizontally extending bar welded at one end to the front of
plate 9.
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A pneumatic cylinder 60 is secured to latch barrel 24 by a threaded end
62 which is threaded, through washer 66, into connector nut 64 which is welded to latch
barrel 24. PnP. lm~tic cylinder 60 has a connector 68 for connecting an air hose 69 from
a source of pressurized air. Pneumatic cylinder 60 operates a retractable pin 70 which
S is spring-biased to the extended position shown in Fig. 5, and which retracts when air
pressure is applied to cylinder 60. When in the extended position, pin 70 extends into
notch 67 when the notch 67 is aligned with it, to hold the latch plunger in place. When
pin 70 is retracted by the air cylinder 60, latch plunger 25 can slide within latch barrel
24 without interference from pin 70. Pin 72 is threaded into the lower end of pin 70,
10 through spacer 71 and allows pin 70 to be m~ml~lly retracted and secured in a retracted
position by cotter pin 73 inserted through hole 74. Cotter pin 73 can be stored in hole
75 when it is not desired to m~nll~lly retract pin 70.
The latch assembly 78 permits an operator to remotely and automatically
release the lifting mechanism from a roll after a roll has been lifted and placed on the
15 ground. In the closed, non-lifting position, latch handle 23 is in the position shown in
Fig. 4 with end 29 of the latch plunger 25 extending into hole 8 of plate 9. In this
position the lifting mechanism 40 can be lifted by plate 1 into and out of the centres of
rolls without gripping, since the toggle arms are held in the lowered position. When the
mechanism 40 has been placed into a position for lifting a roll, latch handle 23 is pulled
20 back until pin 70 extends into notch 67, thus removing and holding the end 29 of plunger
25 from hole 8. When the device is lifted from plate 1, plate 9 moves upwardly to the
position shown in Fig. 2. This causes the ends 20 of the probe to expand and grip the
core of the roll for lifting. When the mechanism 40 and attached roll are lowered to the
ground, the plate 9 lowers until hole 8 is aligned with plunger 25. With the lifting force
25 removed from plate 1, the operator can apply air pressure to cylinder 60, causing pin 70
to retract from notch 67 so that end 29 of plunger 25 is forced into hole 8. Themechanism 40 can then be lifted out of the roll with the toggle arms locked in the closed
position. To operate the latching mechanism m~nll~lly as disclosed in U.S. Patent no.
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5,439,264, in the event air pressure fails, for example, pin 72 is pulled back m~nll~lly
and secured in retracted position by cotter pin 73 through hole 74.
In operation, one or an array of mech~ni~m~ 40 are attached to the lifting
cable of a crane or the like through hole 42. With the toggle arms latched in the lowered
5 position, a worker can insert the probe into the centMl core of the paper roll, which has
a diameter slightly greater than the diameter of sleeve 13 (for new~ ll this is typically
3 inches, 4 inches for Kraft rolls). Once the plate 12 is lowered into contact with the
roll, latch handles 23 are pulled back to put the mech~ni.~m.~ 40 into lifting mode.
Lifting of the plate 1 now causes sleeve 11 and drawbolt 14 to be drawn upwardly with
respect to sleeve 13, and mandrel 21 is similarly forced upwardly through segments 20,
causing them to be forced or wedged outwardly into firm engagement with the inner
surface of the core of the roll. The mechanical advantage provided by the c~mming
action of toggle arms 10 against plate 12 greatly increases the force with which the outer
surface of segments 21 and the related O-rings are driven against the inner core of the
roll to ensure firm gripping. The roll can then be lifted and manipulated into place.
When the operator is satisfied with the location, the lifting cable is lowered to remove
the lifting pressure and lower the toggle arms, air pressure is supplied to cylinders 60 to
release latch plungers 25, and the devices 40 are released from the cores of the rolls.
Existing sources of air pressure, which use an accumulator which gradually builds up air
pressure in the lines after the cylinders have been triggered, may be used, causing a short
delay before the cylinders can be triggered again.
Fig. 6 illustrates a sleeve adapter 80 which allows the standard sleeve 13
used in 3-inch diameter cores, which sleeve is 2- 3/4 inches in diameter, to be expanded
for use in a 4-inch diameter core. Segments 20 are removed from pins 18 and sleeve 83,
which is a cylinder 3-3/4 inches in outer diameter and 2-3/4 inches in inner diameter, is
slid over sleeve 13. Four segments 85, which are similarly of greater diameter than
segments 20, are then pinned on pins 18 through connectors 86, the O-rings 44 are
replaced, and the device can be operated as before but in 4-inch diameter cores. Set
screws 87 are provided to secure sleeve 83 to sleeve 13.
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As will be apparent to those skilled in the art in the light of the foregoing
disclosure, many alterations and modifications are possible in the practice of this
invention without departing from the spirit or scope thereof. For example, while a
pn~llm~tic cylinder 60 has been described, a hydraulic cylinder would also function, as
5 would a solenoid or other electro-mechanical device. Accordingly, the scope of the
invention is to be construed in accordance with the substance defined by the following
claims.
