WO2020187599A1 - Crane - Google Patents

Abstract

The present invention relates to a crane with a height-adjustably mounted control or personnel stand, which can be raised and lowered by at least two lifting elements, wherein the two lifting elements are articulated on a compensating rocker, which is mounted, in such a way that it can rock about a horizontal pivot axis, on a rocker bearing head connected to the control or personnel stand, wherein a monitoring and/or safety device is provided for monitoring and/or ensuring the safety of the control stand. According to the invention, the pivot axis is formed as a measuring axis for detecting the loading state of the rockable mounting of the compensating rocker and providing a loading signal to the monitoring and/or safety device.

Description

crane

The present invention relates to a crane with a height-adjustable mounted control or person station, which can be raised and lowered by at least two lifting elements, the two lifting elements being articulated on a balancing rocker, which can be luffed about a horizontal pivot axis on a with the control or .Wipplager head connected to the person stand is mounted, a monitoring and / or safety device being provided for monitoring and / or ensuring the safety of the control stand.

Height-adjustable control stands can, for example, be longitudinally displaceable on the tower of a crane and thus adjustable in height, whereby such a crane tower can carry a boom in a manner known per se, from which a hoist rope runs to a load hook, possibly via a trolley that can be moved longitudinally on the boom. The said tower can be mounted telescopically and / or tiltable on an upper carriage, which can be mounted on an undercarriage that can be moved on the ground about an upright axis. Such cranes are sometimes referred to as mobile fast-erecting cranes. Basically, the named control station can also be provided on a conventional tower crane, or on another type of crane, whereby the control station does not necessarily have to be movably mounted on a tower, but can also be mounted in a height-adjustable manner in another way.

The control and / or personal stand is often in the form of a cabin or designed as a crane operator and / or lift cabin, and it may be advantageous if such a crane operator cabin can be positioned at different working heights for various lifting tasks of the crane.

In order to guarantee the safety of the height-adjustable control stands or lift cabins, even if people such as the crane driver are transported during the height adjustment, special safety measures are required. On the one hand, there is the provision of two lifting elements connected in parallel in order to be able to achieve the necessary redundancy. On the other hand, however, the proper functioning of the mentioned lifting elements and the suspension of the control stand is additionally monitored in order to be able to detect a malfunction or even a break in good time.

By articulating the two lifting elements on a balancing rocker, the adjustment comfort can be increased, since the mentioned balancing rocker balances the lifting forces of the lifting elements or can compensate to a certain extent for a jerky or not completely synchronous start-up process. The lifting elements mentioned can be lifting ropes which suspend the balancing rocker and thus the control stand from above. In principle, however, it would also be considered to use actuators, for example in the form of pressure cylinders, as Hubele elements that can pull or push the balancing rocker into the desired position.

In order to be able to detect malfunctions such as slack rope, broken rope, rope elongation or incorrect spooling on the drive rope drum, it has already been proposed to adjust the angular position of the compensating rocker by mechanical end Monitor switches that are actuated by a swivel arm of the balancing rocker when the balancing rocker reaches a predetermined pivot or rocker position. The said balancing rocker is usually preloaded into an undeflected neutral position by one or more spring devices, so that the said balancing rocker only rocks up or down and is rotatably deflected to such an extent in the event of major irregularities in the application of force by the two lifting elements the mentioned limit switches are operated. If, for example, one of the hoisting ropes is wound up significantly faster than the other, the balancing rocker is adjusted increasingly more, with a first limit switch, for example, being able to indicate a pre-critical state. If a slack rope forms on the hoist rope, which is drawn in more slowly, or if one of the two hoist ropes breaks completely, so that only the other hoist rope carries the balancing rocker and thus the control stand, maximum rotary deflection will occur, which can be indicated by an additional limit switch.

On the other hand, a “normal” overloading of the elevator car should also be recorded, for example if a person climbs too much into the car or the stand or a person carries equipment that is too heavy, so that the permissible load is only just exceeded. Since the aforementioned limit switches, which show a strong Ver tilt when a hoist rope breaks, do not respond in such close exceedances, additional sensors must be attached in order to be able to detect such an overload condition.

Thus, different critical states can be detected and displayed by cleverly arranging different mechanical limit switches.

The previous safety and / or monitoring devices are, however, relatively complex. If different critical states are to be differentiated, various mechanical limit switches are necessary, whereby the spring loading of the balancing rocker has to be adapted accordingly. On the other hand, it has been the case up to now even with a more complex configuration of the safety and / or monitoring device difficult to carry out the monitoring with sufficient precision to be able to intervene in the control of the crane in good time.

The present invention is therefore based on the object of creating an improved crane of the type mentioned at the outset which avoids the disadvantages of the prior art and further develops the latter in an advantageous manner. In particular, sensitive monitoring of the suspension and the operation of the height-adjustable control and / or personal status is to be achieved with simple means, which can differentiate between different critical states in order not only to enable an emergency shutdown, but also advance measures such as countermeasures for the crane's control device control of the drives or a maintenance notice.

According to the invention, the stated object is achieved by a crane according to claim 1. Preferred embodiments of the invention are the subject of the dependent claims.

It is therefore proposed to integrate the monitoring of the control stand suspension into the pivot axis, which mounts the balancing rocker so that it can be rocked on the rocker bearing part connected to the control stand. The pivot axis serves on the one hand to pivot the balancing rocker and at the same time it detects the load on the rocker mounting so that the pivot axis fulfills a dual function. According to the invention, the pivot axis is designed as a measuring axis for detecting the load state of the rockable mounting of the balancing rocker and providing a load signal to the monitoring and / or safety device. Said measuring axis can in particular be designed as a force measuring bolt, which pivotally connects the balancing rocker to the rocker bearing head and detects at least transverse forces transverse to the pivot axis.

Because the pivot axis is not a normal axle bolt, but also serves as a measuring bolt or measuring axis, the suspension of the control station can Build more compactly and get by with fewer components. At the same time, a sensitive detection of the forces acting between the balancing seesaw and the rocker bearing head is made possible.

In order to be able to differentiate between a normal Überlastzu stood for example too many people in the cabin on the one hand and a mechanical irregularity on the lifting elements and the balancing rocker such as a broken rope or incorrect winding on the other hand with such a simple measuring axis, in an advantageous development of the invention the Compensation rocker and / or the rocker bearing head and / or the measuring axis can be assigned a lever mechanism that converts tilting movements of the compensating rocker and / or the rocker bearing head that exceed a predetermined amount into a noticeable or detectable change in the load on the measuring axis or the bearing forces acting on the measuring axis . Said lever mechanism can in particular be designed to convert a holding and / or braking torque that arises or is necessary for this when stopping and / or braking a relative rotation of the balancing rocker relative to the rocker bearing head into a bearing force acting on the measuring axis. If, for example, one of the hoisting ropes or elements breaks, the balancing rocker itself would rotate until the holding force applied by the remaining lifting element passes vertically through the measuring axis. If, however, the rotation is braked or stopped beforehand, the holding or braking torque required for this can be converted into a force by the aforementioned lever mechanism that significantly changes the load on the measuring axis.

Said lever mechanism can in particular comprise a swivel limiter which allows a specific swiveling between the balancing rocker and rocker bearing head that occurs during normal operation, but limits and / or brakes when a specific swivel angle is reached in order to generate the said holding and / or braking torque and convert it into a Change the load on the measuring axes. In an advantageous development of the invention, pivot stops can be provided on the balancing rocker and the rocker bearing head, which limit the possible pivoting movements of the balancing rocker relative to the rocker bearing head. In particular, the mentioned swivel stops on the balancing rocker and the rocker bearing head can be arranged in such a way that the swivel stops are disengaged in an undeflected neutral position of the balancing rocker and only come into engagement with the rocker bearing head when a predetermined swivel position of the balancing rocker is reached, and a further swivel movement beyond that To block.

By means of such swivel stops, larger changes in the load condition can be generated on the measuring axis when the swivel stops come into engagement, since their leverage changes the load condition on the measuring axis.

In particular, by means of such swivel stops and the resulting changes in the load on the measuring axis, it can be determined which hub element has failed or is hindered or, in general, what quality the malfunction has, even if the measuring axis is not designed to detect the direction of the load , for example if the measuring axis is not rotationally fixed, which is also possible in connection with the swivel stops. Due to the known geometry of the swivel stops and the articulation of the lifting elements and the geometry of the balancing rocker, it is possible to deduce from the change in the load state of the measuring axis what change has occurred in the suspension.

In an advantageous development of the invention, the mentioned pivot stops can be arranged on a pitch circle around the measuring axis, in particular directly adjacent to the outer circumference of the mentioned measuring axis, so that greater changes in the load condition occur due to a relatively short lever arm with respect to the pivot axis when Forces are transmitted via the swivel stops. Advantageously, the mentioned swivel stops can be arranged on a pitch circle around the measuring axis, the diameter of which is less than 300% or also less than 200% or less than 150% of the outer diameter of the mentioned measuring axis.

In an advantageous further development of the invention, the said Schwenkan strikes can be arranged in a horizontal plane which extends transversely to the effective axis of the lifting elements. In particular, when viewed in the direction of the pivot axis, the mentioned pivot stops can be arranged in the range from approximately 2 o'clock to 5 o'clock or in the range from approximately 8 o'clock to 10 o'clock.

The pivot stops can be arranged in such a way that the forces transmitted by the pivot stops when the pivot stops are in engagement run approximately in the direction of the actuating forces of the lifting elements and / or the weight of the control station.

In order to be able to differentiate between different critical states, an evaluation device for evaluating the measurement signal of the measurement axis can be provided in a further development of the invention, which is configured to detect various critical states of the suspension of the control and / or personal status based on the height and / or to determine a change in the measuring signal of the measuring axis. In particular, the named evaluation device can be designed to compare the measurement signal of the measurement axis with different threshold values in order to determine the load state, depending on which threshold value is exceeded or not reached.

For example, the evaluation device can work with a first threshold value, which is located in the range of the permissible load of the control and / or personal status or characterizes a load on the measuring axis, below which a normal operating state can be assumed and when it is exceeded a “normal” excess of the permissible load can be assumed. In other words, said first The threshold value characterizes an operating state in which a transition occurs between the load capacity that is still tolerated and an excessively high load capacity, but no abnormal rotation of the balancing rocker to the rocker bearing head has yet occurred.

Alternatively or additionally, the evaluation device can compare the measurement axis signal with a second threshold value, which characterizes a load on the measurement axis that only occurs when the balancing rocker is abnormally rotated relative to the rocker bearing head, in particular by the mentioned swivel limitation, which limits the swiveling of the balancing rocker to the rocker bearing head and The weight load on the suspension is multiplied by the weight of the control and / or personal status including the load.

In a further development of the invention, the mentioned second threshold value can be more than 20% or more than 40% above a load on the measuring axis, which can occur with maximum permitted loading of the control and / or personal position when the balancing rocker is not deflected or is only slightly deflected or when it is operating properly the screw jack occurs. With such a buffer window between maximum, normal load and excessive load on the measuring axis due to excessive deflection of the balancing rocker, as occurs in the event of a rope break or incorrect winding, the evaluation device can reliably differentiate between normal overload due to too many people on the one hand and damage to the suspension on the other without the need for additional sensors beyond the aforementioned measuring axis.

Said evaluation device can be designed electronically, for example comprise switching elements integrated in the measuring axis sensor system. As an alternative or in addition, the evaluation device can also be part of an electronic control device which, for example, can have a processor and a memory in which the aforementioned threshold values can be stored. For example, said evaluation device can be part of the electronic crane control device. The named measuring axis can basically be designed differently in order to detect the transverse forces acting on the measuring axis in terms of magnitude and / or direction. For example, the measuring axis can be assigned a detection device for detecting an elastic deformation of the measuring axis. For example, one or more strain gauges can be attached to the named measuring axis in order to detect deformations of the measuring pin.

Alternatively or additionally, the measuring axis can be provided with a surface coating that shows a change in the electrical resistance when the measuring pin is deformed. Such a surface coating can be in the form of a thin film coating or in the form of a thin film sensor, for example.

As an alternative or in addition, a magnetic field-based sensor system can be assigned to the measuring axis in order to detect deformations and / or applications of force or stresses acting in the measuring pin. For example, the measuring axis can serve as the iron core of a transformer circuit so that expansion of the measuring axis affects the magnetic properties and thus the voltage on a secondary coil.

In this case, the named measuring axis can be fastened to the rocker bearing head in a rotationally fixed manner, wherein the compensating rocker can be held on the named measuring axis such that it can be rotated relative to the measuring axis. Alternatively, it would also be possible to fasten the named measuring axis to the balancing rocker in a rotationally fixed manner, so that it follows the rocking movements of the balancing rocker and rotates relative to the rocker bearing head.

By defining a predetermined rotational position of the measuring axis, it would be possible to determine the direction of the forces acting on the measuring axis and / or to determine on which sector of the measuring axis the transverse forces act at least predominantly. From the information on which sector the transverse forces act, it could be determined in which relative rotational or rocking position the balancing rocker is located relative to the rocker bearing head. From the mentioned pivoting position of the balancing rocker and rocker bearing head relative to one another, conclusions can be drawn about the load state, in particular unequal positions of the two lifting elements, for example due to asynchronous adjustment.

In principle, however, it is not necessary not to rotationally fix the measuring axis, for example if only an absolute monitoring of the amount of the forces transmitted by the measuring axis between the balancing rocker and the rocker bearing head is to be recorded or monitored, for example to implement overload protection. Such an overload protection can, for example, trigger or intervene if too many people enter the control stand or the guidance of the crane driver's cab jams.

In an advantageous further development of the invention, said rocker bearing head can be rigidly connected to the control stand. Advantageously, said rocker bearing head can be attached directly to the chassis of the control station. In principle, however, it would also be possible to link the mentioned Wipplagerkopf indirectly to the control stand, for example via a link arrangement that holds the Wippla gerkopf at the control stand.

In a further development of the invention, said lifting elements are limp to gel elements, in particular in the form of lifting ropes. Pull chains or belts are also conceivable.

Alternatively, the mentioned lifting elements can also be designed in the form of actuators such as hydraulic cylinders, in which case the balancing rocker can also be pressurized, for example in the sense of upward pressure forces. The present invention is explained in more detail using a preferred Ausfüh approximately example and associated drawings. In the drawings show:

1: a schematic side view of a tower crane designed as a tower crane

Fast-erecting crane according to an advantageous embodiment of the invention, the crane operator's cabin is mounted on the tower of the crane in a height-adjustable manner,

FIG. 2: a perspective view of the crane operator's cab from FIG. 1 and its suspension,

3: a perspective view of the suspension of the crane operator's cab from FIG. 2, which shows the compensating seesaw with the two lifting ropes connected to it, as well as the measuring axis through which the compensating seesaw is hinged to the rocker bearing head of the suspension,

4: a plan view of the balancing rocker and the measuring axis of the suspension from the preceding figures, the balancing rocker being shown in an undeflected neutral position in which the pivot stops are disengaged, and

Fig. 5: a plan view of the balancing rocker and the measuring axis similar to Fi gur 4, wherein the balancing rocker is shown in a twisted position due to breakage or slack rope of one of the hoisting ropes, in which the pivot stops have come into engagement.

As FIG. 1 shows, the crane 1 can be designed as a tower crane and have a tower 2 which stands upright during operation and supports a cantilevered boom 3. The tower 2 can sit with its lower end on a revolving platform 4, which is rotatable about an upright axis and supported on an undercarriage 5, which can be designed as a truck or movable in another way, but can optionally also form a rigid, non-movable support base.

A trolley 7, which can be moved back and forth by means of a trolley rope 8, can be mounted on the boom 3 so that it can move longitudinally. A hoisting rope 6 with a load hook can run over the trolley 7.

The crane 1 comprises a control and / or personal stand 9, which can be designed as a crane driver or elevator cabin 10. Said control and / or Perso nenstand 9 is mounted adjustable in height. In particular, the mentioned crane operator or elevator cabin 10 can be mounted on the tower 2 so that it can be moved longitudinally, for example by a cabin chassis that is guided on the tower profile, for example its longitudinal belts.

As FIGS. 2 to 5 show, the control and / or personal stand 9 can be held by a suspension 11 and brought into different height positions that can attack the chassis, in particular the top of the crane operator or lift cab. Said cabin 10 can be moved up and down on an outside of the tower 2, for example by means of a roller guide or rail guide along the tower. If necessary, however, the cabin can also be arranged inside the tower profile, for example if it is only used as a climbing aid to reach the boom or a control stand arranged above and the tower profile is sufficiently voluminous.

Said suspension 11 can in particular include a balancing rocker 12, to which two lifting elements 13 in the form of lifting ropes can be articulated, which can be raised and lowered via a suitable hoist drive. For example, two cable drums can be provided that can wind up and unwind the two hoisting cables.

The said balancing rocker 12 is by means of a pivot axis 14, which extends lying low and engages a central portion of the balancing rocker 12, pivotally mounted on a rocker bearing head 15, which can be rigidly connected to the control stand 9, in particular attached to the chassis of the cabin 10.

As FIG. 3 shows, the mentioned rocker bearing head 15 can form, for example, a bearing yoke, between the legs of which the compensating rocker 12 with a bearing section is immersed, wherein the limbs of the rocker bearing head 15 and the bearing section of the compensating rocker 12 can have aligned swivel bearing bores through which said pivot axis 14 extends. In principle, however, it would also be possible to turn the arrangement around, for example to provide two yoke legs on the bearing section of the compensating rocker 12, between which the rocker bearing head 15 extends. Further designs, for example in the manner of a cantilevered pivot bearing connection, would also be possible.

The named pivot axis 14 is designed as a measuring axis 16 in order to be able to detect transverse forces acting on the pivot axis 14. Said measuring axis 16 can be designed in the manner of a force measuring pin, where a suitable sensor system can be provided on measuring axis 16, which can detect the named bearing forces and loads acting on the pin. As mentioned at the outset, said sensor system 17 can comprise, for example, strain gauges on the measuring axis or a thin film coating applied to it in order to be able to measure deformations and thus loads.

As a comparison of FIGS. 4 and 5 shows, the named measuring axis 16 can be held non-rotatably on the rocker bearing head 15 so that it does not join in the rotational movements of the compensating rocker 12. Alternatively, the measuring axis 16 can also be mounted so that it can be rotated relative to the rocker bearing head 15 and / or to the compensating rocker 12, so that it does not assume a predetermined rotational position.

The pivotability of the balancing rocker 12 relative to the rocker bearing head 15 can advantageously be limited by pivot stops 18 which can be provided on the balancing rocker 12 and the rocker bearing head 15. In particular, said swivel stops 18 can about the swivel axis 14 around be arranged immediately in the vicinity of the outer circumference, so in particular special around the bearing bores through which the pivot axis 14 he stretches.

For example, said swivel stops 18 can be formed by projections that are ausgebil det on the balancing rocker 12 and the rocker bearing head 15 to collide with each other when the balancing rocker 12 pivots relative to the rocker bearing head 15.

As FIGS. 4 and 5 show, when the compensating rocker 12 is in an undeflected neutral position, which is shown in FIG. 4, the mentioned swivel stops 18 can be disengaged from one another, so that the compensating rocker 12 can rotate unimpeded from the neutral position. On the other hand, the pivot stops 18 come into engagement when the balancing rocker has executed a predetermined pivoting movement, for example by an angle of approximately +/- 10 ° to +/- 20 °.

If the pivot stops 18 come into engagement with one another, as FIG. 5 shows, for example because one of the lifting elements 13 is broken or has been unwound too far, the load condition on the measuring axis 16 changes significantly. The eccentrically arranged pivot stops 18 and the forces transmitted thereby act on the pivot axis 14 with additional forces which have to compensate for the lever situation. The loads detected on the measuring axis 16, in particular transverse forces and / or bending moments, experience a significant change as soon as the pivot stops 18 come into engagement. This change can in principle be a relief or an additional load that can be recorded on the measuring axis.

Advantageously, said pivot stops 18 are designed so that engagement forces arise on the engaging stop surfaces that are eccentric with respect to pivot axis 14 and / or have a lever arm in order to generate a reaction in the measurement axis. In particular, a resulting de engagement force with engaged swivel stops act eccentrically to the measuring axis.

As FIGS. 4 and 5 show, the swivel stops 18 can comprise two pairs of swivel stops 18 which are arranged on opposite sides of the measuring axis 16, preferably approximately - at least approximately - in a plane that extends horizontally through the swivel axis 14. For example, the pivot stops 18 can extend in a range from 2 o'clock to 4 o'clock or 8 o'clock to 10 o'clock when the pivot axis 14 is viewed in its axial direction.

The pivot stops 18 are advantageously arranged in such a way that, depending on the tilting movement of the compensating rocker, only one pair of stops comes into engagement on one side of the pivot axis 14.

The pivot stops 18 form a lever mechanism which converts the torque or holding torque that occurs when the pivoting movement of the balancing rocker 12 is limited into a significant change in the load on the measuring axis 16. In particular, the lever mechanism formed by the swivel stops 18 can multiply the load introduced by the cabin into the suspension, so that the load on the measuring axis 16 increases significantly, in particular increases much more strongly than would be the case if the permissible load capacity was only slightly exceeded for example if an additional person gets on.

As Fig. 5 shows, when a pair of swivel stops engages with further rotation of the balancing rocker, on the one hand a lever arm of the measuring axis or the cabin load passing through the measuring axis to the pair of swiveling stops that is in engagement and on the other hand a lever arm of the still supporting rope 13 to the pair of swivel stops 18, the lever arms mentioned each being essentially the horizontal distance between the center of the measuring axis and the point of engagement of the swivel stops. On the other hand, or the line of action of the cable tensile force and the point of engagement of the Schwenkan strokes 18 on the other hand can correspond.

Since the rope force in the still supporting rope 13 corresponds to the load of the car plus the load and attachments, so that a vertical balance of forces can result, the change in the load on the measuring axis can be controlled by the length of the lever arms mentioned.

For example, the length of the mentioned lever arms can be designed by appropriate design of the geometry of the balancing rocker and the rocker bearing head, in particular the articulation point of the lifting elements 13 on the balancing rocker and the arrangement of the pivot stops 18, so that the load occurring on the measuring axis 16 and thus measured increases by 50% or more when the mentioned swivel stops 18 come into engagement by corresponding swiveling of the balancing rocker 12. For example, if the cabin 10 weighs 1000 kg along with the maximum permissible load, the aforementioned lever arms can be set such that a load of 1500 kg occurs on the measuring axis 16 when the pivot stops 18 engage. In this respect, it is easy to differentiate between normal overloading and a broken rope or incorrect spooling, for example if a first threshold of 1050 kg has been exceeded and a second threshold of 1400 kg, for example, has not yet been exceeded, so that normal overloading is even more functional Suspension can be assumed, while if the said second threshold value of, for example, 1400 kg is exceeded, a cable break or incorrect winding can be assumed. The values mentioned are only to be understood as examples.

The sensor system 17 assigned to the measuring axis 16 emits a load signal which characterizes the load situation on the measuring axis 16, in particular indicating the transverse forces occurring there in terms of their magnitude and / or direction. Said load signal of the sensor system 17 can be evaluated by a control device 20 of the crane 1, which control device 20 is electronically designed and can include, for example, a microprocessor that can process a control program stored in a memory.

Said control device 20 can have an evaluation device 19 which evaluates the measurement signal of the measuring axis 16 in the manner mentioned, in particular compares it with two threshold values that characterize on the one hand the normal transition from normal, permissible payload to overloading and on the other hand the engagement of the swivel stops 18 and the associated change in the load on the measuring axis.

Said control device 20 can on the one hand emit a warning signal and / or shut down at least one drive of the crane, in particular the lifting plant drive for the height adjustment of the control stand 9, if the load signal of the sensors 17 indicates an exceptional load condition, for example excessive transverse forces on the Measuring axis.

As an alternative or in addition, however, the named control device 20 can also intervene preventively in the control of the drives if necessary. If the sensor system 17 determines, for example, that the balancing rocker tilts too much, the control device 20 can try to readjust the hoist drive from which the too slack or too tight hoist rope runs.

Alternatively or additionally, the control device 20 can also emit a preventive maintenance signal if the load signals of the sensor system 17 do not yet indicate a critical state, but already show significant changes compared to the original load spectrum when new.

Claims

Claims 1. A crane, in particular a fast-erecting crane, comprising a telescopic and / or luffing tower (2), with a height-adjustable control and / or personal stand (9) which can be raised and lowered by two lifting elements (13), the two lifting elements ( 13) are articulated to a compensating rocker (12) which is mounted to rock about a horizontal pivot axis (14) on a rocker bearing head (15) connected to the control and / or personal stand (9), with a monitoring and / or Safety device (21) for monitoring the control and / or personal status (9) is provided, characterized in that the pivot axis (14) acts as a measuring axis (16) for detecting the load condition of the luffing bearing of the balancing rocker (12) and providing a Load signal to the monitoring and / or safety device (21) is formed. 2. Crane according to the preceding claim, wherein the balancing rocker (12) and / or the rocker bearing head (15) and / or the measuring axis (16) has a lever mechanism for generating a displacement acting on the measuring axis (16) change in the load on the measuring axis as a function of a rotation of the balancing rocker (12) relative to the rocker bearing head (15). 3. Crane according to the preceding claim, wherein said Hebelme mechanism is designed to limit and / or brake the rotation of the balancing rocker (12) relative to the rocker bearing head (15) occurring holding and / or braking torque in one on the measuring axis (16) to implement acting load. 4. Crane according to one of the preceding claims, wherein on the balancing rocker (12) and the rocker bearing head (15) pivot stops (18) are provided, which are disengaged in an undeflected neutral position of the balancing rocker (12) and when a predetermined pivot position is reached Compensating rocker (12) come into engagement and block further pivoting movement of the compensating rocker (12) relative to the rocker bearing head (15). 5. Crane according to the preceding claim, wherein the pivot stops (18) are arranged on a pitch circle around the measuring axis (16) and / or adjacent to the outer circumference of the measuring axis (16). 6. Crane according to the preceding claim, wherein said pitch circle has a diameter of less than 300% or less than 200% of the outer diameter of the measuring axis (16). 7. Crane according to one of claims 4 to 6, wherein the pivot stops (18) are arranged in a horizontal plane transversely to the luffing axis of the lifting elements (13). 8. Crane according to one of claims 4 to 7, wherein the pivot stops (18) are designed to generate a resulting impact force in their engaged position, which acts eccentrically to the axis of rotation (14). 9. Crane according to one of the preceding claims, wherein an Auswertein direction (19) for evaluating the measurement signal of the measurement axis (16) is provided. The said evaluation device (19) is designed to use a level and / or a change in the measurement signal of the measurement axis (16) between overloading of the control and / or passenger station (9) when the lifting elements (13 ) and the balancing rocker (12) on the one hand and a malfunction of the lifting elements (13) and / or the balancing rocker (12) on the other. 10. Crane according to the preceding claim, wherein said evaluation device (19) is designed to compare the measurement signal of the measurement axis (16) with two different threshold values, a first of which the load on the measurement axis (16) at the transition between maximum permissible siger loading and overloading of the control and / or personal status (9) with the intended operating state of the lifting elements (13) and the balancing rocker (12) and a second an increase in the load on the measuring axis (16) with excessive deflection of the balancing rocker (12) characterized from their neutral position. 11. Crane according to one of the preceding claims, wherein the measuring axis (16) rotatably on the rocker bearing head (15) is attached and the balancing rocker (12) is rotatable to the measuring axis (16) on said measuring axis (16) keep GE. 12. Crane according to one of the preceding claims, wherein the measuring axis (16) is designed to detect transverse forces on the measuring axis (16) in terms of amount and / or direction. 13. Crane according to one of the preceding claims, wherein the measuring axis (16) is designed to detect bending moments on the measuring axis. 14. Crane according to one of the preceding claims, wherein the measuring axis (16) comprise a sensor system (17), at least one strain gauge and / or a stretch-sensitive thin film coating and / or a magnetic field based sensor arrangement. 15. Crane according to one of the preceding claims, wherein the rocker bearing head (15) is rigidly attached to the control and / or personal stand (9). 16. Crane according to one of the preceding claims, wherein the at least two lifting elements (13) are each designed as pliable tension elements, in particular lifting ropes. 17. Crane according to one of the preceding claims, wherein the compensating rocker pe (12) with its articulation points of the lifting elements (13) and the pivot axis (14) defines a triangle, preferably a connecting line de through the articulation points of the lifting elements (13) above the Pivot axis (14) is arranged. 18. Crane according to the preceding claim, wherein the pivot axis (14) in the undeflected neutral position of the compensating rocker (12) is positioned centrally between the articulation points of the lifting elements (13) on the compensating rocker (12).