FIELD OF THE INVENTION AND PRIOR ART
[0001] The present invention relates to a load handling crane according to the preamble
of claim 1.
[0002] A load handling crane in the form of a conventional lorry crane or forestry crane
normally comprises a column, which is rotatable about a vertical axis of rotation,
and a crane boom system, which is mounted to the column and which is intended to carry
a load via a load handling tool suspended at a boom tip of the crane boom system,
i.e. at the outer end of the outermost crane boom of the crane boom system. The load
handling crane also comprises a manoeuvring unit with one or more manoeuvring members
configured to be manoeuvrable by a crane operator in order to control the crane boom
movements. The individual movements of the crane booms of the crane boom system are
regulated by an electronic control device based on control signals from the manoeuvring
unit.
[0003] The manoeuvring unit is normally portable and configured to be carried by the crane
operator, for instance by means of a waist belt or harness.
[0004] Some load handling cranes are provided with a high seat arrangement with an elevated
platform mounted to the column of the crane and with an operator's seat arranged in
the open air on the platform, wherein the crane operator, when controlling the crane
boom movements, may sit on the operator's seat with a good view over the working area
of the crane.
OBJECT OF THE INVENTION
[0005] The object of the present invention is to improve the possibilities for a crane operator
to use a portable manoeuvring unit in a convenient manner when being seated on an
operator's seat of a high seat arrangement of the above-mentioned type.
SUMMARY OF THE INVENTION
[0006] According to the present invention, said object is achieved by means of a load handling
crane having the features defined in claim 1.
[0007] The load handling crane according to the invention comprises:
- a crane base;
- a column which is rotatably mounted to the crane base so as to be rotatable in relation
to the crane base about an essentially vertical axis of rotation;
- an actuator for rotating the column;
- a crane boom system comprising two or more liftable and lowerable crane booms which
are articulately connected to each other, and hydraulic cylinders for lifting and
lowering the crane booms, wherein a first crane boom of the crane boom system is articulately
connected to the column and a second crane boom of the crane boom system is articulately
connected to the first crane boom;
- an electronic control device for controlling said actuator and said hydraulic cylinders
so as to control the rotation of the column and the movement of the crane booms;
- a portable manoeuvring unit with one or more manoeuvring members configured to be
manoeuvrable by a crane operator in order to control the position of the crane booms,
wherein the portable manoeuvring unit is configured to transmit control signals to
the electronic control device related to the manoeuvring of said manoeuvring members;
and
- a high seat arrangement comprising a high seat platform and an operator's seat, wherein
the high seat platform is connected to the column so as to be rotatable in relation
to the crane base together with the column, and wherein the operator's seat is mounted
to the high seat platform.
According to the invention, the high seat arrangement comprises a stand, which is
mounted to the high seat platform, and an attachment configured for releasable engagement
with the portable manoeuvring unit, wherein the attachment is fixed to the stand and
wherein the manoeuvring unit is detachably mountable to the attachment in order to
allow the manoeuvring unit to be carried by the stand. The stand is configured to
position the attachment in such a position in front of the operator's seat that a
crane operator sitting on the operator's seat is allowed to manoeuvre said manoeuvring
members on the portable manoeuvring unit when it is mounted to the attachment. Hereby,
there is no need for the crane operator to hold the portable manoeuvring unit in an
awkward position in his/her lap when sitting on the operator's seat. On the contrary,
the crane operator may mount the portable manoeuvring unit to the attachment on the
stand and let the stand keep the manoeuvring unit in a comfortable position in relation
to the operator's seat. When so desired, the crane operator may control the crane
standing on the ground with the portable manoeuvring unit detached from the attachment
on the stand and carried in a conventional manner by the crane operator by means of
a waist belt or harness.
[0008] According to an embodiment of the invention, the stand is pivotally mounted to the
high seat platform, wherein the stand is pivotable in relation to the high seat platform
between a use position, in which the stand keeps the attachment in an advanced position
close to the operator's seat, and a non-use position, in which the stand keeps the
attachment in a retracted position further away from the operator's seat. The stand
is intended to be moved from the non-use position to the use position when the crane
operator has climbed up onto the high seat platform and placed himself/herself on
the operator's seat. When the crane operator later on is to leave the high seat platform,
the stand is intended to be moved from the use position to the non-use position. Hereby,
the portable manoeuvring unit may be positioned close to operator's seat in an ergonomically
suitable position when the crane operator is sitting on the operator's seat and moved
away from the operator's seat in order to leave room for the crane operator when he/she
moves into or out of the operator's seat.
[0009] Another embodiment of the invention is characterized in:
- that the stand comprises a base and a pillar, wherein the base is pivotally mounted
to the high seat platform through a joint which forms a horizontal pivot axis for
the stand; and
- that the pillar has a lower end and an upper end, wherein the pillar is fixed to the
base at its lower end and said attachment is fixed to the upper end of the pillar.
Hereby, the stand may be moved between the use-position and the non-use position in
a simple manner.
[0010] According to another embodiment of the invention, the pillar is telescopically extensible
in order to allow an adjustment of the vertical position of said attachment by an
adjustment of the length of the pillar. Hereby, the stand can easily be adapted to
suit the length of the crane operator.
[0011] According to another embodiment of the invention, said attachment is pivotally connected
to the upper end of the pillar and moveable into different pivotal positions in relation
to the pillar in order to allow an adjustment of the inclination of the attachment
in relation to the pillar and thereby an adjustment of the inclination of the attachment
in relation to the operator's seat, wherein the attachment is lockable to the pillar
in a desired pivotal position by means of a locking mechanism. Hereby, the crane operator
can easily adjust the inclination of the portable manoeuvring unit as desired.
[0012] According to another embodiment of the invention, the stand is biased towards the
non-use position by a lockable gas spring, wherein the stand is pivotable from the
non-use position to the use position against the action of the lockable gas spring
and pivotable from the use position to the non-use position under the action of the
lockable gas spring. The lockable gas spring makes it possible for the crane operator
to position and lock the stand in a desired pivotal position in a simple and rapid
manner.
[0013] Another embodiment of the invention is characterized in:
- that the load handling crane comprises a first support leg arranged on a first side
of the crane base, a second support leg arranged on an opposite second side of the
crane base, one or more first actuators for moving the first support leg in relation
to the crane base and one or more second actuators for moving the second support leg
in relation to the crane base, wherein the electronic control device is configured
to control the first and second actuators to thereby allow a crane operator to control
the movement of the first and second support legs via the portable manoeuvring unit;
- that a manually activatable first confirmation member is accessible on the first side
of the crane base, wherein the electronic control device is configured to allow the
first support leg to be moved under the control of the portable manoeuvring unit when
the electronic control device has received a confirmation signal indicating that the
first confirmation member has been manually activated;
- that a manually activatable second confirmation member is accessible on the second
side of the crane base, wherein the electronic control device is configured to allow
the second support leg to be moved under the control of the portable manoeuvring unit
when the electronic control device has received a confirmation signal indicating that
the second confirmation member has been manually activated;
- that the high seat arrangement comprises a detecting device for detecting the mounting
of the portable manoeuvring unit to said attachment;
- that the electronic control device is configured to allow the first and second support
legs to be moved under the control of the portable manoeuvring unit when the electronic
control device has received a detecting signal from the detecting device indicating
that the portable manoeuvring unit has been mounted to said attachment; and
- that the electronic control device is configured to prevent the first and second support
legs from being moved under the control of the portable manoeuvring unit when the
electronic control device has not received any confirmation signal indicating that
the first or second confirmation member has been manually activated or any detecting
signal indicating that the portable manoeuvring unit has been mounted to said attachment.
When the crane operator controls the crane while standing on the ground with the portable
manoeuvring unit carried in a conventional manner by means of a waist belt or harness,
the crane operator has to manually activate the first confirmation member in order
to move the support leg on the first side of the crane and manually activate the second
confirmation member in order to move the support leg on the opposite second side of
the crane. This conventional safety function makes sure that the crane operator is
positioned on the same side of the crane as the support leg to be moved and consequently
is able to observe the operating area of the support leg in question. The above-mentioned
detecting device makes it possible for the crane operator to move the support legs
via the portable manoeuvring unit from the high seat platform without any preceding
activation of the confirmation members. From the elevated position at the high seat
platform, the crane operator has a good view over the operating areas of the support
legs on both sides of the crane and the confirmation members on the opposite sides
of the crane base may therefore be disregarded by the electronic control device, for
the convenience of the crane operator and without jeopardizing the safety, when the
detecting device confirms to the electronic control device that the portable manoeuvring
unit is mounted to the attachment on the stand at the high seat platform.
[0014] Further advantageous features of the load handling crane according to the present
invention will appear from the description following below and the dependent claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The invention will in the following be more closely described by means of embodiment
examples, with reference to the appended drawings. In the drawings:
- Fig 1
- is a perspective view of a load handling crane according to an embodiment of the present
invention,
- Figs 2 and 3
- are perspective views of a high seat arrangement included in the load handling crane
of Fig 1, as seen with the stand of the high seat arrangement in a use position,
- Fig 4
- is a perspective view of the high seat arrangement of Figs 2 and 3, as seen with the
stand in a non-use position,
- Fig 5
- is a perspective view of a portable manoeuvring unit and an attachment for the manoeuvring
unit on the stand, as seen with the manoeuvring unit detached from the attachment,
- Fig 6
- is a perspective view of the portable manoeuvring unit and the attachment, as seen
with the manoeuvring unit mounted to the attachment,
- Fig 7
- is a perspective view from below of a part of the high seat arrangement of Figs 2-4,
- Fig 8
- is a schematic, partly cut, lateral view of parts included in the high seat arrangement
of Figs 2-4, as seen with the stand in the non-use position,
- Figs 9 and 10
- are schematic, partly cut, lateral views corresponding to Fig 8, as seen with the
stand in the use position,
- Fig 11
- is a schematic detail enlargement of a part of a lockable gas spring included in the
high seat arrangement of Figs 2-4, as seen with a valve member of the lockable gas
spring in closed position,
- Fig 12
- is a schematic detail enlargement corresponding to Fig 11, as seen with the valve
member in open position, and
- Fig 13
- is an outline diagram of parts included in a load handling crane according to the
invention.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0016] In this description, the expression "liftable and lowerable crane boom" refers to
a crane boom which can be pivoted in a vertical plane so as to thereby perform liftings
and lowerings of a load carried by the crane. The expression "hydraulic cylinder for
lifting and lowering the crane boom" here refers to the hydraulic cylinder which is
associated with the liftable and lowerable crane boom and which carries out the pivoting
thereof in a vertical plane.
[0017] Fig 1 shows a hydraulic load handling crane 1 according to an embodiment of the present
invention. The crane 1 comprises a crane base 4, which is to be connected to the chassis
of a vehicle, for instance in the form of a lorry.
[0018] The crane 1 further comprises:
- a column 5, which is rotatably mounted to the crane base 4 so as to be rotatable in
relation to the crane base about an essentially vertical axis of rotation by means
of an actuator 6, for instance in the form of a hydraulic cylinder;
- a liftable and lowerable first crane boom 7, here denominated inner boom, which is
articulately connected to the column 5 in such a manner that it is pivotable in relation
to the column about an essentially horizontal axis of rotation;
- a first hydraulic cylinder 8 for lifting and lowering the inner boom 7 in relation
to the column 5;
- a liftable and lowerable second crane boom 9, here denominated outer boom, which is
articulately connected to the inner boom 7 in such a manner that it is pivotable in
relation to the inner boom 7 about an essentially horizontal axis of rotation; and
- a second hydraulic cylinder 10 for lifting and lowering the outer boom 9 in relation
to the inner boom 7.
[0019] In the illustrated embodiment, the crane boom system 11 of the crane 1 is formed
by the inner boom 7 and the outer boom 9 and the associated hydraulic cylinders 8,
10. However, the crane boom system 11 of the crane 1 may as an alternative include
more than two liftable and lowerable crane booms articulately connected to each other.
One or more of the crane booms of the crane boom system 11 may be telescopically extensible,
for instance by means of one or more hydraulic cylinders, in order to enable an adjustment
of the extension length thereof.
[0020] In the illustrated embodiment, the outer boom 9 is telescopically extensible and
comprises a base section 9a and several telescopic crane boom sections 9b which are
mutually slidable in relation to each other in the longitudinal direction of the outer
boom 9 for adjustment of the extension length thereof. The telescopic crane boom sections
9b are displaceable in relation to the base section 9a and in relation to each other
by means of hydraulic cylinders 12 carried by the outer boom 9.
[0021] The load handling crane 1 is provided with a support leg arrangement 20 for supporting
the crane. The support leg arrangement 20 comprises a base structure 21 fixedly connected
to the crane base 4 and at least two support legs 22a, 22b moveably mounted to the
base structure 21 on opposite sides of the crane base 4. In the illustrated embodiment,
the support leg arrangement 20 comprises a first support leg 22a provided on a first
side of the crane base 4 and a second support leg 22b provided on an opposite second
side of the crane base 4, wherein each support leg 22a, 22b is moveable in a horizontal
direction in relation to the crane base 4 by means of an actuator (not shown), for
instance in the form of a hydraulic cylinder or any other suitable type of linear
actuator, between a retracted position close to the base structure 21 and an extended
position (see Fig 1) at a further distance from the base structure 21. In the illustrated
embodiment, each support leg 22a, 22b is fixed at the outer end of a telescopically
extensible support leg beam 23a, 23b, which is slidably mounted to the base structure
21 so as to be horizontally moveable in relation to the base structure. Furthermore,
each support leg 22a, 22b is telescopically extensible in a vertical direction by
means of an actuator 24a, 24b, for instance in the form of a hydraulic cylinder or
any other suitable type of linear actuator. A foot plate 25a, 25b is provided at the
outer end of each support leg 22a, 22b, wherein this foot plate 25a, 25b is moveable,
by a vertical extension of the support leg, from a non-use position (see Fig 1), in
which the foot plate 25a, 25b is lifted from the ground, to an operating position,
in which the foot plate 25a, 25b is in supporting contact with the ground. As an alternative,
each support leg 22a, 22b could be pivotally mounted to the base structure 21 of the
support leg arrangement 20 so as to be pivotable by means of an actuator, for instance
in the form of a hydraulic cylinder, between a non-use position and an operating position.
[0022] The load handling crane 1 is also provided with a high seat arrangement 30 comprising
a high seat platform 31 and an operator's seat 32 mounted to the high seat platform.
The operator's seat 32 is arranged in the open air on the high seat platform 31. The
high seat platform 31 is fixedly connected to the column 5 at an elevated position
and is rotatable in relation to the crane base 4 together with the column 5. Thus,
the high seat platform 31 and the operator's seat 32 rotate together with the crane
boom system 11 and the column 5 about the above-mentioned vertical axis of rotation
when the column 5 is rotated in relation to the crane base 4 by means of the actuator
6. The crane operator may sit on the operator's seat 32 when controlling the movement
of the support legs 22a, 22a and the movement of the crane booms 7, 9. From the elevated
position at the high seat platform 31, the crane operator has a good view over the
operating areas of the support legs 22a, 22a and over the working area of the crane
boom system 11. The crane operator may climb up to the high seat platform 31 through
a ladder 33, which is fixedly connected to the crane base 4.
[0023] The load handling crane 1 comprises a portable manoeuvring unit 60 with one or more
maneuvering members 61a, 61 b (see Figs 2-4) configured to be manoeuvrable by the
crane operator in order to control the movement of the support legs 22a, 22b, the
rotation of the column 5 and the movement of the crane booms 7, 9. Control signals
are transmitted via a wireless connection from the portable manoeuvring unit 60 to
an electronic control device 70 (very schematically illustrated in Fig 13), which
in its turn controls the above-mentioned hydraulic cylinders and actuators of the
crane 1 in a conventional manner in dependence on the control signals from the portable
manoeuvring unit 60 related to the manoeuvring of the manoeuvring members 61a, 61
b. The electronic control device 70 comprises a microprocessor or the similar for
processing the control signals from the portable manoeuvring unit 60.
[0024] The manoeuvring members 61 a, 61 b may for instance consist of joysticks, as shown
in Figs 2-4, but any other suitable type of manoeuvring members may also be used,
such as for instance toggle levers or the similar.
[0025] The high seat arrangement 30 comprises a stand 34, which is mounted to the high seat
platform 31, and an attachment 35 configured for releasable engagement with the portable
manoeuvring unit 60. The attachment 35 is fixed to the stand 34 and the manoeuvring
unit 60 is detachably mountable to the attachment 35 in order to allow the manoeuvring
unit 60 to be firmly fixed to and carried by the stand 34. The stand 34 is capable
of positioning the attachment 35 in such a position in front of the operator's seat
32 that a crane operator sitting on the operator's seat 32 will be able to manoeuvre
the manoeuvring members 61a, 61 b on the portable manoeuvring unit 60 in a convenient
manner when the manoeuvring unit 60 is mounted to the attachment 35. The stand 34
is preferably adjustable so as to allow an adjustment of the position of the attachment
35 in relation to the operator's seat 32.
[0026] The stand 34 is with advantage pivotally mounted to the high seat platform 31, wherein
the stand 34 is pivotable in relation to the high seat platform 31 between a use position
(see Figs 2 and 3), in which the stand 34 keeps the attachment 35 in an advanced position
close to the operator's seat 32, and a non-use position (see Fig 4), in which the
stand 34 keeps the attachment 35 in a retracted position further away from the operator's
seat 32.
[0027] In the illustrated embodiment, the stand 34 comprises a base 36 and a pillar 37,
wherein the base 36 is pivotally mounted to the high seat platform 31 through a joint
38 (see Figs 8-10) which forms a horizontal pivot axis for the stand. The pillar 37
has a lower end and an upper end, wherein the pillar 37 is fixed to the base 36 at
its lower end and the attachment 35 is fixed to the upper end of the pillar.
[0028] In the illustrated example, the base 36 has the form of an elongated bar with a first
end 36a and an opposite second end 36b, wherein the base 36 is pivotally mounted to
the high seat platform 31 at its first end 36a and the pillar 37 is fixed to the base
36 at the second end 36b thereof. The pillar 37 is preferably fixed to the base 36
with the longitudinal axis of the pillar 37 extending perpendicularly to the longitudinal
axis of the base 36.
[0029] The pillar 37 is with advantage telescopically extensible in order to allow an adjustment
of the vertical position of the attachment 35 by an adjustment of the length of the
pillar. In the illustrated embodiment, the pillar 37 comprises a lower pillar part
37a (see Figs 3 and 6) and an upper pillar part 37b, wherein the upper pillar part
37b is telescopically connected to the lower pillar part 37a and axially moveable
into different displacement positions in relation to the lower pillar part 37a in
order to allow an adjustment of the length of the pillar 37. The upper pillar part
37b is lockable to the lower pillar part 37a in a desired displacement position by
means of a manually manoeuvrable locking mechanism 38.
[0030] The attachment 35 is with advantage pivotally connected to the upper end of the pillar
37 and moveable into different pivotal positions in relation to the pillar 37 in order
to allow an adjustment of the inclination of the attachment 35 in relation to the
pillar 37 and thereby an adjustment of the inclination of the attachment 35 in relation
to the operator's seat 32. The attachment 35 is lockable to the pillar 37 in a desired
pivotal position by means of a manually manoeuvrable locking mechanism 39.
[0031] In the illustrated embodiment, the attachment 35 comprises two pin-shaped attachment
members 35a, 35b, which are insertable into a respective recess 63a, 63b provided
in a housing 64 of the portable manoeuvring unit 60, as illustrated in Figs 5 and
6. However, the attachment 35 may of course also be configured to engage with the
portable manoeuvring unit 60 in any other suitable manner.
[0032] In the illustrated embodiment, the stand 34 is biased towards the non-use position
by a lockable gas spring 40 (see Figs 7-12) of a conventional type, wherein the stand
34 is pivotable from the non-use position to the use position against the action of
the lockable gas spring 40 and pivotable from the use position to the non-use position
under the action of the lockable gas spring 40.
[0033] The lockable gas spring 40 comprises:
- a cylinder part 41;
- a first piston 42a received in the cylinder part 41;
- first and second fluid chambers 43a, 43b which are provided in the cylinder part 41
and separated from each other by the first piston 42a, wherein the fluid chambers
43a, 43b are filled with a fluid and are fluidly connectable to each other via a fluid
passage 44 in the first piston 42a;
- a valve member 45 arranged in the first piston 42a, wherein the valve member 45 is
moveable between an open position, in which the valve member 45 keeps the fluid passage
44 open and thereby allows fluid to flow between the fluid chambers 43a, 43b, and
a closed position, in which the valve member 45 blocks the fluid passage 44 and thereby
prevents fluid from flowing between the fluid chambers 43a, 43b;
- a piston rod 46 fixed to the first piston 42a and extending through the first fluid
chamber 43a;
- an operating rod 47 for controlling the valve member 45, the operating rod extending
through an axial bore 48 in the piston rod 46 and being operatively connected to the
valve member 45;
- a second piston 42b received in the cylinder part 41; and
- a gas chamber 43c which is provided in the cylinder part 41 and separated from the
second fluid chamber 43b by the second piston 42b.
[0034] The piston rod 46 extends through a seal 59a and a guide member 59b provided at the
end of the cylinder part 41.
[0035] The first and second fluid chambers 43a, 43b are filled with a hydraulic fluid, preferably
in the form of oil, and the gas chamber 43c is filled with pressurized gas, for instance
in the form of nitrogen.
[0036] Under the effect of an external force, the operating rod 47 is moveable in relation
to the piston rod 46 from a first position (see Figs 8, 9 and 11), in which the valve
member 45 is in the closed position, to a second position (see Figs 10 and 12), in
which the operating rod 47 keeps the valve member 45 in the open position. When the
valve member 45 is in the closed position, no fluid is allowed to flow between the
fluid chambers 43a, 43b, and the cylinder part 41 is thereby prevented from moving
axially in relation to the piston rod 46. When the valve member 45 is in the open
position, fluid is allowed to flow between the fluid chambers 43a, 43b, and the cylinder
part 41 is thereby allowed to move axially in relation to the piston rod 46. When
the external force on the operating rod 47 is released, the valve member 45 returns
from the open position to the closed position under the effect of the pressure from
the fluid in the fluid chamber 43b on the piston side of the lockable gas spring 40.
[0037] The illustrated gas spring 40 is a lockable gas spring of a type which is rigid in
compression, but the gas spring 40 could as an alternative be a lockable gas spring
of any other suitable type.
[0038] The cylinder part 41 of the lockable gas spring 40 is articulately connected to the
base 36 of the stand 34 through a joint 49, which forms a horizontal pivot axis between
the stand 34 and the lockable gas spring 40. The piston rod 46 of the lockable gas
spring 40 is articulately connected to the high seat platform 31 through a joint 50,
which forms a horizontal pivot axis between the high seat platform 31 and the lockable
gas spring 40. The last-mentioned joint 50 is formed by a pivot member 51, which is
rotatably mounted to the high seat platform 31, wherein the outer end of the piston
rod 46 is firmly fixed to this pivot member 51.
[0039] The high seat arrangement 30 comprises a manoeuvring mechanism 52 which is operatively
connected to the operating rod 47 of the lockable gas spring 40, wherein a crane operator
sitting on the operator's seat 32 is capable of exerting a pushing force on the operating
rod 47 by means of the manoeuvring mechanism 52 in order to move the operating rod
from the above-mentioned first position to the above-mentioned second position. In
the illustrated embodiment, the manoeuvring mechanism 52 comprises a foot lever 53
arranged on the high seat platform 31 and a motion transferring member 54 for transferring
a depression of the foot lever 53 into a movement of the operating rod 47 from the
first position to the second position. The foot lever 53 is arranged within reach
for a crane operator sitting on the operator's seat 32. The motion transferring member
54 is pivotally mounted to the high seat platform 31 through a joint 55 which forms
a horizontal pivot axis for the motion transferring member 54. The foot lever 53 is
fixed to a first end 54a (see Fig 7) of the motion transferring member 54 and the
operating rod 47 is in contact with a contact surface 56 (see Fig 8) at an opposite
second end 54b of the motion transferring member 54. In the illustrated example, the
motion transferring member 54 has the form of an elongated and angled plate, but it
may of course be designed in any other suitable manner. The crane operator may effect
a movement of the valve member 45 to the open position by depressing the foot lever
53. As long as the foot lever 53 remains in the depressed position, the crane operator
may manually pivot the stand 34 to a desired pivotal position in order to position
the portable manoeuvring unit 60 in a suitable position in front of the operator's
seat 32. When the crane operator releases the foot lever 53, the valve member 45 returns
to the closed position and the stand 34 is thereby locked in its prevailing position.
The crane operator may later on effect an automatic return of the stand 34 to the
non-use position by depressing the foot lever 53 and keeping it depressed for a short
period of time, which will cause the lockable gas spring 40 to expand under the effect
of the pressure from the fluid in the fluid chamber 43b on the piston side of the
lockable gas spring.
[0040] A manually activatable first confirmation member 26a (see Figs 1 and 13) is accessible
on the first side of the crane base 4, wherein the electronic control device 70 is
configured to allow the first support leg 22a to be moved under the control of the
portable manoeuvring unit 60 when the electronic control device 70 has received a
confirmation signal indicating that the first confirmation member 26a has been manually
activated. A manually activatable second confirmation member 26b (very schematically
illustrated in Fig 13) is accessible on the opposite second side of the crane base
4, wherein the electronic control device 70 is configured to allow the second support
leg 22b to be moved under the control of the portable manoeuvring unit 60 when the
electronic control device 70 has received a confirmation signal indicating that the
second confirmation member 26b has been manually activated. Each confirmation member
26a, 26b may for instance have the form of a mechanical push button, a mechanical
lever or a virtual push button on a touch screen.
[0041] The high seat arrangement 30 comprises a detecting device 57 (very schematically
illustrated in Fig 13) for detecting the mounting of the portable manoeuvring unit
60 to the attachment 35 on the stand 34, wherein the electronic control device 70
is configured to allow the first and second support legs 22a, 22b to be moved under
the control of the portable manoeuvring unit 60 when the electronic control device
70 has received a detecting signal from the detecting device 57 indicating that the
portable manoeuvring unit 60 has been mounted to the attachment 35. The detecting
device 57 may for instance comprise a proximity sensor 58, which is arranged on the
attachment 35 and configured to sense the presence of the portable manoeuvring unit
60 when the portable manoeuvring unit has been mounted to the attachment 35. However,
the detecting device 57 may also comprise any other suitable type of sensor for detecting
the mounting of the portable manoeuvring unit 60 to the attachment 35, such as for
instance a micro switch.
[0042] The electronic control device 70 is configured to prevent the first and second support
legs 22a, 22b from being moved under the control of the portable manoeuvring unit
60 when the electronic control device 70 has not received any confirmation signal
indicating that the first or second confirmation member 26a, 26b has been manually
activated or any detecting signal from the detecting device 57 indicating that the
portable manoeuvring unit 60 has been mounted to the attachment 35. Thus, the support
leg 22a on the first side of the crane base 4 may only be moved under the control
of the portable manoeuvring unit 60 when the confirmation member 26a on the first
side of the crane base 4 has been manually activated or when it is detected by the
detecting device 57 that the portable manoeuvring unit 60 is mounted to the attachment
35 on the stand 34. In the corresponding manner, the support leg 22b on the second
side of the crane base 4 may only be moved under the control of the portable manoeuvring
unit 60 when the confirmation member 26b on the second side of the crane base 4 has
been manually activated or when it is detected by the detecting device 57 that the
portable manoeuvring unit 60 is mounted to the attachment 35 on the stand 34.
[0043] The invention is of course not in any way limited to the embodiments described above.
On the contrary, several possibilities to modifications thereof should be apparent
to a person skilled in the art without thereby deviating from the basic idea of the
invention as defined in the appended claims.
1. A load handling crane comprising:
- a crane base (4);
- a column (5) which is rotatably mounted to the crane base (4) so as to be rotatable
in relation to the crane base about an essentially vertical axis of rotation;
- an actuator (6) for rotating the column (5);
- a crane boom system (11) comprising two or more liftable and lowerable crane booms
(7, 9), which are articulately connected to each other, and hydraulic cylinders (8,
10) for lifting and lowering the crane booms (7, 9), wherein a first crane boom (7)
of the crane boom system is articulately connected to the column (5) and a second
crane boom (9) of the crane boom system is articulately connected to the first crane
boom (7);
- an electronic control device (70) for controlling said actuator (6) and said hydraulic
cylinders (8, 10) so as to control the rotation of the column (5) and the movement
of the crane booms (7, 9);
- a portable manoeuvring unit (60) with one or more manoeuvring members (61 a, 61
b) configured to be manoeuvrable by a crane operator in order to control the position
of the crane booms (7, 9), wherein the portable manoeuvring unit (60) is configured
to transmit control signals to the electronic control device (70) related to the manoeuvring
of said manoeuvring members (61 a, 61 b); and
- a high seat arrangement (30) comprising a high seat platform (31) and an operator's
seat (32), wherein the high seat platform (31) is connected to the column (5) so as
to be rotatable in relation to the crane base (4) together with the column, and wherein
the operator's seat (32) is mounted to the high seat platform (31),
characterized in:
- that the high seat arrangement (30) comprises a stand (34), which is mounted to the high
seat platform (31), and an attachment (35) configured for releasable engagement with
the portable manoeuvring unit (60), wherein the attachment (35) is fixed to the stand
(34) and wherein the manoeuvring unit (60) is detachably mountable to the attachment
(35) in order to allow the manoeuvring unit (60) to be carried by the stand (34);
and
- that the stand (34) is configured to position the attachment (35) in such a position in
front of the operator's seat (32) that a crane operator sitting on the operator's
seat (32) is allowed to manoeuvre said manoeuvring members (61a, 61 b) on the portable
manoeuvring unit (60) when it is mounted to the attachment (35).
2. A load handling crane according to claim 1, characterized in that the stand (34) is pivotally mounted to the high seat platform (31), wherein the stand
(34) is pivotable in relation to the high seat platform (31) between a use position,
in which the stand (34) keeps said attachment (35) in an advanced position close to
the operator's seat (32), and a non-use position, in which the stand (34) keeps said
attachment (35) in a retracted position further away from the operator's seat (32).
3. A load handling crane according to claim 2,
characterized in:
- that the stand (34) comprises a base (36) and a pillar (37), wherein the base (36) is
pivotally mounted to the high seat platform (31) through a joint (38) which forms
a horizontal pivot axis for the stand (34); and
- that the pillar (37) has a lower end and an upper end, wherein the pillar (37) is fixed
to the base (36) at its lower end and said attachment (35) is fixed to the upper end
of the pillar.
4. A load handling crane according to claim 3, characterized in that the base (36) has the form of an elongated bar with a first end (36a) and an opposite
second end (36b), wherein the base (36) is pivotally mounted to the high seat platform
(31) at its first end (36a) and the pillar (37) is fixed to the base (36) at the second
end (36b) thereof.
5. A load handling crane according to claim 4, characterized in that the pillar (37) is fixed to the base (36) with the longitudinal axis of the pillar
extending perpendicularly to the longitudinal axis of the base (36).
6. A load handling crane according to any of claims 3-5, characterized in that the pillar (37) is telescopically extensible in order to allow an adjustment of the
vertical position of said attachment (35) by an adjustment of the length of the pillar.
7. A load handling crane according to any of claims 3-6, characterized in that said attachment (35) is pivotally connected to the upper end of the pillar (37) and
moveable into different pivotal positions in relation to the pillar (37) in order
to allow an adjustment of the inclination of the attachment (35) in relation to the
pillar (37) and thereby an adjustment of the inclination of the attachment (35) in
relation to the operator's seat (32), wherein the attachment (35) is lockable to the
pillar (37) in a desired pivotal position by means of a locking mechanism (39).
8. A load handling crane according to any of claims 2-7, characterized in that the stand (34) is biased towards the non-use position by a lockable gas spring (40),
wherein the stand (34) is pivotable from the non-use position to the use position
against the action of the lockable gas spring (40) and pivotable from the use position
to the non-use position under the action of the lockable gas spring (40).
9. A load handling crane according to claim 8,
characterized in that the lockable gas spring (40) comprises:
- a cylinder part (41);
- a piston (42a) received in the cylinder part (41);
- two separate fluid chambers (43a, 43b) which are provided in the cylinder part (41)
and separated from each other by the piston (42a), wherein the fluid chambers (43a,
43b) are filled with a fluid and are fluidly connectable to each other via a fluid
passage (44) in the piston (42a);
- a valve member (45) arranged in the piston (42a), wherein the valve member (45)
is moveable between an open position, in which the valve member keeps the fluid passage
(44) open and thereby allows fluid to flow between said fluid chambers (43a, 43b),
and a closed position, in which the valve member (45) blocks the fluid passage (44)
and thereby prevents fluid from flowing between said fluid chambers (43a, 43b);
- a piston rod (46) fixed to the piston (42a); and
- an operating rod (47) for controlling the valve member (45), the operating rod extending
through an axial bore (48) in the piston rod (46) and being operatively connected
to the valve member (45), wherein the operating rod (47), under the effect of an external
force, is moveable in relation to the piston rod (46) from a first position, in which
the valve member (45) is in the closed position, to a second position, in which the
operating rod (47) keeps the valve member (45) in the open position.
10. A load handling crane according to claim 9, characterized in that the high seat arrangement (30) comprises a manoeuvring mechanism (52) which is operatively
connected to the operating rod (47) of the lockable gas spring (40), wherein a crane
operator sitting on the operator's seat (32) is allowed to exert a force on the operating
rod (47) by means of the manoeuvring mechanism (52) in order to move the operating
rod from said first position to said second position.
11. A load handling crane according to claim 10,
characterized in that the manoeuvring mechanism (52) comprises:
- a foot lever (53) arranged on the high seat platform (31); and
- a motion transferring member (54) for transferring a depression of the foot lever
(53) into a movement of the operating rod (47) from said first position to said second
position.
12. A load handling crane according to claim 11, characterized in that the motion transferring member (54) is pivotally mounted to the high seat platform
(31) and has a first end (54a) and an opposite second end (54b), wherein the foot
lever (53) is fixed to the first end (54a) of the motion transferring member (54)
and the operating rod (47) is in contact with a contact surface (56) at the second
end (54b) of the motion transferring member (54).
13. A load handling crane according to claim 12, characterized in that the motion transferring member (54) has the form of an elongated and angled plate.
14. A load handling crane according to any of claims 1-13,
characterized in:
- that the load handling crane (1) comprises a first support leg (22a) arranged on a first
side of the crane base (4), a second support leg (22b) arranged on an opposite second
side of the crane base (4), one or more first actuators for moving the first support
leg (22a) in relation to the crane base (4) and one or more second actuators for moving
the second support leg (22b) in relation to the crane base (4), wherein the electronic
control device (70) is configured to control the first and second actuators to thereby
allow a crane operator to control the movement of the first and second support legs
(22a, 22b) via the portable manoeuvring unit (60);
- that a manually activatable first confirmation member (26a) is accessible on the first
side of the crane base (4), wherein the electronic control device (70) is configured
to allow the first support leg (22a) to be moved under the control of the portable
manoeuvring unit (60) when the electronic control device (70) has received a confirmation
signal indicating that the first confirmation member (26a) has been manually activated;
- that a manually activatable second confirmation member (26b) is accessible on the second
side of the crane base (4), wherein the electronic control device (70) is configured
to allow the second support leg (22b) to be moved under the control of the portable
manoeuvring unit (60) when the electronic control device (70) has received a confirmation
signal indicating that the second confirmation member (26b) has been manually activated;
- that the high seat arrangement (30) comprises a detecting device (57) for detecting the
mounting of the portable manoeuvring unit (60) to said attachment (35);
- that the electronic control device (70) is configured to allow the first and second support
legs (22a, 22b) to be moved under the control of the portable manoeuvring unit (60)
when the electronic control device (70) has received a detecting signal from the detecting
device (57) indicating that the portable manoeuvring unit (60) has been mounted to
said attachment (35); and
- that the electronic control device (70) is configured to prevent the first and second
support legs (22a, 22b) from being moved under the control of the portable manoeuvring
unit (60) when the electronic control device (70) has not received any confirmation
signal indicating that the first or second confirmation member (26a, 26b) has been
manually activated or any detecting signal indicating that the portable manoeuvring
unit (60) has been mounted to said attachment (35).
15. A load handling crane according to claim 14, characterized in that the detecting device (57) comprises a proximity sensor (58), which is arranged on
said attachment (35) and configured to sense the presence of the portable manoeuvring
unit (60) when the portable manoeuvring unit has been mounted to the attachment (35).