A boom working device has a boom, mounted on and extending from a boom support, on which an end effector mounting interface is formed. The boom is equipped with two linear output structures, each in engagement with one of two drive wheels of the boom support. With respect to the boom support, the boom is both pivotable around a main axis and also capable of linear movement at right-angles to the main axis. Through harmonised rotary actuation of the drive wheels an operating movement of the boom may be generated, consisting either of a pivoting movement alone or of a linear movement alone or of the pivoting movement with simultaneously superimposed linear movement.

A boom working device has a boom, mounted on and extending from a boom support, on which an end effector mounting interface is formed. The boom is equipped with two linear output structures, each in engagement with one of two drive wheels of the boom support. With respect to the boom support, the boom is both pivotable around a main axis and also capable of linear movement at right-angles to the main axis. Through harmonised rotary actuation of the drive wheels an operating movement of the boom may be generated, consisting either of a pivoting movement alone or of a linear movement alone or of the pivoting movement with simultaneously superimposed linear movement.

The focus of the present disclosure is on portable cranes and cantilevered base systems. In particular, portable cranes and cantilevered base systems which are lightweight, easy-to-operate, safe, inexpensive, and have extended reaches with high-load capacities would be advantageous for a variety of applications. A cantilevered support to a pivotable arm that is provided by the present disclosure provides advantages when compared to other portable cranes, such as the ability to: 1) extend an arm and reach of a crane, 2) increase a load that can be lifted or lowered, 3) operate a portable crane and cantilevered base system freestanding without attaching a base to a floor, surface, or bed of a vehicle, and 4) augment the structural capacity of a portable crane and cantilevered base with mechanical devices to support a variety of applications.

The focus of the present disclosure is on portable cranes and cantilevered base systems. In particular, portable cranes and cantilevered base systems which are lightweight, easy-to-operate, safe, inexpensive, and have extended reaches with high-load capacities would be advantageous for a variety of applications. A cantilevered support to a pivotable arm that is provided by the present disclosure provides advantages when compared to other portable cranes, such as the ability to: 1) extend an arm and reach of a crane, 2) increase a load that can be lifted or lowered, 3) operate a portable crane and cantilevered base system freestanding without attaching a base to a floor, surface, or bed of a vehicle, and 4) augment the structural capacity of a portable crane and cantilevered base with mechanical devices to support a variety of applications.

An improved building access system includes a turntable having an upper surface and a lower surface, a main tower attached to the turntable's upper surface, a boom tower pivotally attached to the turntable and disposed so as to form an angle with the main tower, and a balancing tower also pivotally attached to the turntable and also disposed so as to form an angle with the main tower. It also includes means for changing these angles between the main tower and, respectively, the boom tower and the balancing tower, and a cathead pivotally attached to the end of the boom tower which is opposite the end attached to the turntable. The inventive apparatus also includes pressure sensing devices located and disposed so as to measure the pressure at each mounting point where the main tower is attached to the turntable, along with one or more leveling rods disposed so that, as the boom tower is raised upwardly and the angle between the main tower and the boom tower decreases in value by an associated amount, the angle between the cathead and the boom tower decreases in value by the same amount. The turntable may further include at least one support arm configured so that the bending forces experienced by the turntable are transferred to a larger diameter support structure. The invention also includes an elongated beam member which is especially useful for forming box beams, which member has a pair of symmetrical planar side elements which are perpendicular to each other and which are also connected together by a diagonal element.

An improved building access system includes a turntable having an upper surface and a lower surface, a main tower attached to the turntable's upper surface, a boom tower pivotally attached to the turntable and disposed so as to form an angle with the main tower, and a balancing tower also pivotally attached to the turntable and also disposed so as to form an angle with the main tower. It also includes means for changing these angles between the main tower and, respectively, the boom tower and the balancing tower, and a cathead pivotally attached to the end of the boom tower which is opposite the end attached to the turntable. The inventive apparatus also includes pressure sensing devices located and disposed so as to measure the pressure at each mounting point where the main tower is attached to the turntable, along with one or more leveling rods disposed so that, as the boom tower is raised upwardly and the angle between the main tower and the boom tower decreases in value by an associated amount, the angle between the cathead and the boom tower decreases in value by the same amount. The turntable may further include at least one support arm configured so that the bending forces experienced by the turntable are transferred to a larger diameter support structure. The invention also includes an elongated beam member which is especially useful for forming box beams, which member has a pair of symmetrical planar side elements which are perpendicular to each other and which are also connected together by a diagonal element.

The present invention relates to a method for weathervaning of a crane which has a boom which can rotate about a vertical axis, a slewing gear motor and a slewing gear service brake for securing the boom in a rotational position with a securing torque in the crane mode, wherein in the case of a crane which has been out-of-operation, the boom is braked against rotation with an out-of-operation mode braking torque which is less than said securing torque in the crane mode. In this respect, the invention also relates to such a crane itself, in particular in the form of a revolving tower crane. In accordance with the invention, the out-of-operation mode braking torque is kept at least approximately constant over the range of the speed of rotation and over the range of the angle of rotation of the boom.

The present invention relates to a method for weathervaning of a crane which has a boom which can rotate about a vertical axis, a slewing gear motor and a slewing gear service brake for securing the boom in a rotational position with a securing torque in the crane mode, wherein in the case of a crane which has been out-of-operation, the boom is braked against rotation with an out-of-operation mode braking torque which is less than said securing torque in the crane mode. In this respect, the invention also relates to such a crane itself, in particular in the form of a revolving tower crane. In accordance with the invention, the out-of-operation mode braking torque is kept at least approximately constant over the range of the speed of rotation and over the range of the angle of rotation of the boom.

The invention relates to a method of weathervaning a work machine in out-of-operation mode, in particular of weathervaning a revolving crane/revolving tower crane or a concrete spreader mast, wherein the work machine comprises at least one slewing part that is rotatable about a substantially vertical axis by means of a slewing gear, and wherein in a first step one or more wind data are measured by means of a measurement system arranged at the work machine; an optimum position of the slewing part is determined for an optimum weathervaning in dependence on the detected wind data; and the slewing gear drive is subsequently correspondingly actuated to bring the slewing part into the determined position

The invention relates to a method of weathervaning a work machine in out-of-operation mode, in particular of weathervaning a revolving crane/revolving tower crane or a concrete spreader mast, wherein the work machine comprises at least one slewing part that is rotatable about a substantially vertical axis by means of a slewing gear, and wherein in a first step one or more wind data are measured by means of a measurement system arranged at the work machine; an optimum position of the slewing part is determined for an optimum weathervaning in dependence on the detected wind data; and the slewing gear drive is subsequently correspondingly actuated to bring the slewing part into the determined position