The invention relates to a chassis comprising a base (12) and four wheels (14) each being mounted on the base by way of a respective supporting device (16) and each being capable of being brought out of a transport position into an operating position of the chassis (10), and vice versa, wherein each supporting device comprises a support or carrier arm (18), which is arranged on the base via a proximal end (20) to be pivotable out of the transport position into the operating position of the chassis, and vice versa, and at a distal end (22) receives an axle journal (24) for rotation, a first control (30) for pivoting the support or carrier arm out of the transport position into the operating position of the chassis, and vice versa, the axle journal rotatably arranged at the distal end of the support or carrier arm, a stub axle (40), which is pivotably arranged on the axle journal and receives the wheel for rotation at a distal end (42) of the axle journal; and a second control (44) for pivoting the stub axle against the axle journal.

A bridge crane arrangement includes at least one main girder having a central web and a bottom flange; end girders supporting opposite ends of the main girder; a slide arranged between an end girder and the main girder, the slide allowing the movement of the end girder in relation to the main girder in at least its longitudinal direction and the rotation of the end girder and main girder in relation to each other; and a restrictor to restrict the movements between the end girder and the main girder. On the top surface of the end girder, there is arranged a support platform wider than the bottom flange, the slide includes a slide surface arranged on the top surface of the support platform and/or the bottom surface of the bottom flange, and the restrictor is arranged to the support platform on both sides of the bottom flange.

A mobile crane has an undercarriage, a superstructure arranged on the undercarriage, a slewing gear by which the superstructure may be rotated relative to the undercarriage, a slewing gear brake that acts on the slewing gear to brake a rotation of the superstructure, and a jib mounted on the superstructure as to be adjustable in luffing angle and/or in length. The mobile crane additionally contains a dolly coupling arranged on the jib and by which the jib is coupled to a mobile crane dolly during dolly travel with the superstructure in an extended position. The mobile crane further has a sensor interface for connecting a dolly coupling sensor, and a controller that is adapted to ascertain during dolly travel, in dependence on a signal received from the dolly coupling sensor, whether the jib rests on the mobile crane doll, and to activate the slewing gear brake if it does not.

A mobile crane has an undercarriage, a superstructure arranged on the undercarriage, a slewing gear by which the superstructure may be rotated relative to the undercarriage, a slewing gear brake that acts on the slewing gear to brake a rotation of the superstructure, and a jib mounted on the superstructure as to be adjustable in luffing angle and/or in length. The mobile crane additionally contains a dolly coupling arranged on the jib and by which the jib is coupled to a mobile crane dolly during dolly travel with the superstructure in an extended position. The mobile crane further has a sensor interface for connecting a dolly coupling sensor, and a controller that is adapted to ascertain during dolly travel, in dependence on a signal received from the dolly coupling sensor, whether the jib rests on the mobile crane doll, and to activate the slewing gear brake if it does not.

Systems and methods for a mobile crane are provided. In particular, systems and methods are provided for a mobile crane that is designed to enable easy transportation on a railcar to and from a job site. The mobile crane facilitates quick changing between a transport configuration and a work configuration to enable increased productivity. The mobile crane is configured to be modular and thereby be configured to include various lifting and object manipulating features, as required by a specific application.

The invention provides a crane assembly for lifting a load comprising: a pair of guides (2) positioned parallel to one another; a carriage (4,40) associated with each guide (2) and movable along each guide (2); a bridge (1) having an attachment point (8) for attaching the load, the bridge (1) being attached between the carriages (4,40) through connector arms (3), each connector arm (3) being attached through a lower end (31) to the bridge (1) and pivotable (5) at least about an axis perpendicular to the bridge, each connector arm (3) being attached at an upper end (32) to the corresponding carriage (4,40) through a multi-axis joint (33,35); wherein each multiaxis joint (33,35) is connected to the corresponding carriage (4,40) through a low friction thrust bearing (6)configured to rotate with initial movement of the corresponding carriage (4,40).

The invention provides a crane assembly for lifting a load comprising: a pair of guides (2) positioned parallel to one another; a carriage (4,40) associated with each guide (2) and movable along each guide (2); a bridge (1) having an attachment point (8) for attaching the load, the bridge (1) being attached between the carriages (4,40) through connector arms (3), each connector arm (3) being attached through a lower end (31) to the bridge (1) and pivotable (5) at least about an axis perpendicular to the bridge, each connector arm (3) being attached at an upper end (32) to the corresponding carriage (4,40) through a multi-axis joint (33,35); wherein each multiaxis joint (33,35) is connected to the corresponding carriage (4,40) through a low friction thrust bearing (6)configured to rotate with initial movement of the corresponding carriage (4,40).

A crawler crane includes a lower traveling body, and the lower traveling body includes: a car body; a right crawler device and a left crawler device; a front side connecting portion; and a rear side connecting portion, the right crawler device includes a right crawler frame, the left crawler device includes a left crawler frame, the front side connecting portion is separably joined to each of a front end portion of the car body, the right crawler frame front portion and the left crawler frame front portion, the rear side connecting portion is separably joined to each of a rear end portion of the car body, the right crawler frame rear portion and the left crawler frame rear portion, and each of the front side connecting portion and the rear side connecting portion includes a lattice portion which has a lattice structure.

A crawler crane includes a lower traveling body, and the lower traveling body includes: a car body; a right crawler device and a left crawler device; a front side connecting portion; and a rear side connecting portion, the right crawler device includes a right crawler frame, the left crawler device includes a left crawler frame, the front side connecting portion is separably joined to each of a front end portion of the car body, the right crawler frame front portion and the left crawler frame front portion, the rear side connecting portion is separably joined to each of a rear end portion of the car body, the right crawler frame rear portion and the left crawler frame rear portion, and each of the front side connecting portion and the rear side connecting portion includes a lattice portion which has a lattice structure.

Provided is a crane which can suppress deformation and vibration of a crane structure in travel and stop of the crane. Inverters are installed respectively in travel devices which are arranged on the opposite sides with a gap in a transverse direction. Each of the inverters independently measures a torque generated in a motors to which the inverter is connected and reduces the rotation speed in the command from a controller to the motor such that the greater the measured torque is, the greater a ratio of reduction is.