The present invention is configured so that it is possible to select any one of a first mode in which a first adjustment valve 13 and a second adjustment valve 20 operate solely on the basis of manipulation of a main manipulation tool (turning lever 8i), a second mode in which the first adjustment valve 13 operates solely on the basis of manipulation of the main manipulation tool (8i) and the second adjustment valve 20 operates solely on the basis of manipulation of a secondary manipulation tool (brake pedal 8j), and a third mode in which the first adjustment valve 13 operates solely on the basis of manipulation of the main manipulation tool (8i) and the second adjustment valve 20 operates on the basis of manipulation of the secondary manipulation tool (8j) while operating on the basis of manipulation of the main manipulation tool (8i).

The present invention is configured so that it is possible to select any one of a first mode in which a first adjustment valve 13 and a second adjustment valve 20 operate solely on the basis of manipulation of a main manipulation tool (turning lever 8i), a second mode in which the first adjustment valve 13 operates solely on the basis of manipulation of the main manipulation tool (8i) and the second adjustment valve 20 operates solely on the basis of manipulation of a secondary manipulation tool (brake pedal 8j), and a third mode in which the first adjustment valve 13 operates solely on the basis of manipulation of the main manipulation tool (8i) and the second adjustment valve 20 operates on the basis of manipulation of the secondary manipulation tool (8j) while operating on the basis of manipulation of the main manipulation tool (8i).

This crane is provided with: a operable functional part that is supported on a pair of lower bases; a driving device; a detection unit that detects information about the attitude of the operable functional part; a target signal generation unit that generates a target signal regarding the moving direction and the moving speed of a suspended load on the basis of information about an operation input for instructing the moving direction and the moving speed of the suspended load; a filter unit that generates a filtering target signal by filtering the target signal; a control signal generation unit that generates a speed control signal for controlling the operation speed of the driving device on the basis of the information about the attitude and the filtering target signal; and a control unit that controls the driving device on the basis of the speed control signal.

A control system for a construction machine stops an upper swing structure at a desired swing stop angle. A main controller sets a swing stop target angle at which an upper swing structure is to be stopped. A swing stoppability determination section reads an angle signal of the upper swing structure with respect to an undercarriage and an angle of a work implement, and determines whether the swing of the upper swing structure can be stopped at the swing stop target angle. A work implement is controlled in such a manner that an extension action of the work implement in a swing radial direction is prohibited or a contraction action of the work implement in the swing radial direction is executed in response to a signal that indicates whether the swing can be stopped and that is determined by the swing stoppability determination section.

A control system for a construction machine stops an upper swing structure at a desired swing stop angle. A main controller sets a swing stop target angle at which an upper swing structure is to be stopped. A swing stoppability determination section reads an angle signal of the upper swing structure with respect to an undercarriage and an angle of a work implement, and determines whether the swing of the upper swing structure can be stopped at the swing stop target angle. A work implement is controlled in such a manner that an extension action of the work implement in a swing radial direction is prohibited or a contraction action of the work implement in the swing radial direction is executed in response to a signal that indicates whether the swing can be stopped and that is determined by the swing stoppability determination section.

A drive control system includes an electric motor, a capacitor, a revolution sensor, a driving device, and a control device. The driving device causes the capacitor to supply electric power to the electric motor to operate the electric motor and causes the capacitor to store the electric power, generated by the electric motor, to brake a turning body. The driving device configured as above is driven by driving electric power supplied from the capacitor. When a charging stop condition is satisfied, the control device stops the driving electric power supplied from the capacitor to the driving device. The charging stop condition is a condition that a turning speed detected by the revolution sensor is a predetermined speed or less while the turning body is decelerating.

A drive control system includes an electric motor, a capacitor, a revolution sensor, a driving device, and a control device. The driving device causes the capacitor to supply electric power to the electric motor to operate the electric motor and causes the capacitor to store the electric power, generated by the electric motor, to brake a turning body. The driving device configured as above is driven by driving electric power supplied from the capacitor. When a charging stop condition is satisfied, the control device stops the driving electric power supplied from the capacitor to the driving device. The charging stop condition is a condition that a turning speed detected by the revolution sensor is a predetermined speed or less while the turning body is decelerating.

A system and method for retaining a linear actuator on a crane component such as a mast is disclosed. In the system a retaining mechanism is mounted on either a body of the linear actuator or the crane component and a catch is mounted to the other of the body or the crane component. Retraction of a rod of the linear actuator causes a cap on the rod to contact the retaining mechanism, which causes the retaining mechanism to move into a latched configuration securing the linear actuator.

A rotation control system may be provided for a material handling machine. The rotation control system may include a boom and a work tool attached to the boom. A swing motor may be capable of swinging the boom and the work tool. A work tool motor may be capable of rotating the work tool relative to the boom. An input device may generate a first signal indicative of a desired swinging of the boom and a second signal indicative of a desired rotation of the work tool. A controller may be in communication with the input device, the swing motor, and the work tool motor. The controller may be capable of actuating the work tool motor based only on the second signal during a first mode of operation and may be capable of actuating the work tool motor based on swinging of the boom during a second mode of operation.

A rotation control system may be provided for a material handling machine. The rotation control system may include a boom and a work tool attached to the boom. A swing motor may be capable of swinging the boom and the work tool. A work tool motor may be capable of rotating the work tool relative to the boom. An input device may generate a first signal indicative of a desired swinging of the boom and a second signal indicative of a desired rotation of the work tool. A controller may be in communication with the input device, the swing motor, and the work tool motor. The controller may be capable of actuating the work tool motor based only on the second signal during a first mode of operation and may be capable of actuating the work tool motor based on swinging of the boom during a second mode of operation.