A method for controlling a hydraulic actuator (2) of a system (1) by means of a valve having a valve element is described. A position of the valve element determines a pressure supplied to a hydraulic actuator (2). In such a method a variable dead band should be minimized. To this end a start position of the valve element is preadjusted as a function of at least one parameter outside the hydraulic actuator (2).

A vehicle crane having a boom that can be luffed between a storage position and a working position within a vertical luffing plane by at least two luffing cylinders The luffing cylinders that lie opposite one another on the luffing plane, enclosing a spread angle between their longitudinal axes in the working position, and the luffing cylinders acting on the boom outside its ends. The longitudinal axis, projected onto the luffing plane, of one luffing cylinder and a vertical direction extending within the luffing plane enclose an angle of inclination there between when the boom is in the storage position to achieve a compact design, particularly when the boom is in the storage position.

A vehicle crane having a boom that can be luffed between a storage position and a working position within a vertical luffing plane by at least two luffing cylinders The luffing cylinders that lie opposite one another on the luffing plane, enclosing a spread angle between their longitudinal axes in the working position, and the luffing cylinders acting on the boom outside its ends. The longitudinal axis, projected onto the luffing plane, of one luffing cylinder and a vertical direction extending within the luffing plane enclose an angle of inclination there between when the boom is in the storage position to achieve a compact design, particularly when the boom is in the storage position.

A turning control apparatus, for a turning-type working machine, includes: a target stop position setting unit setting the target stop position of the turning body and a turning command unit. The target stop position setting unit includes an image taking device, an image processing device forming an overhead view image of the work machine and surrounding objects based on the taken image; an image display command unit making a target stop position setting image including the overhead view image be displayed on a display screen of the image display device, a setting operation member to which a position setting operation for setting a target stop position with reference to the position of the image of the work machine and surrounding objects included in the overhead view image is applied, and a target stop position determination unit that determines a target stop position based on the position setting operation.

An informing device is an informing device mounted on a work vehicle that includes a lower base body, and a swivel body swivelably provided at the lower base body. The informing device includes a first detection unit that detects the actual amount of rotation of a drive device which swivels the swivel body or a driven part driven by the drive device, and a notification unit that issues a notification regarding information corresponding to the amount of rotation detected by the first detection unit.

Provided is a parking brake apparatus installable on a work machine. The parking brake apparatus includes: a parking brake switchable between a braking state of braking the turning of an upper turning body and a braking release state; a brake operation device to which a braking operation and a braking release operation for switching the parking brake to the braking state and the braking release state, respectively, is applied by an operator; and a braking control unit. The braking control unit judges whether or not a turning judgment requirement for judging whether or not the upper turning body is performing a turning motion is satisfied, and performs a braking operation invalidation control to invalidate the braking operation applied to the brake operation device when judging the turning motion is being performed.

A hydraulic circuit for use on a construction machine includes a first valve, a second valve, and at least a third valve. The second and third valve each includes at least one inlet port connected to a first outlet port of the first valve. The first outlet port of each of the second and third valves are configured to reduce a first pressure to a second pressure and/or a third pressure downstream of the second valve and the third valve, respectively. The second valve and the third valve also include at least a second outlet port connected to a reservoir tank. A hydraulic motor is connected to the first outlet port of the second valve, which operates the hydraulic motor in a first direction. The hydraulic motor also is connected to the first outlet port of the third valve, which operates the hydraulic motor in a second direction.

A hydraulic circuit for use on a construction machine includes a first valve, a second valve, and at least a third valve. The second and third valve each includes at least one inlet port connected to a first outlet port of the first valve. The first outlet port of each of the second and third valves are configured to reduce a first pressure to a second pressure and/or a third pressure downstream of the second valve and the third valve, respectively. The second valve and the third valve also include at least a second outlet port connected to a reservoir tank. A hydraulic motor is connected to the first outlet port of the second valve, which operates the hydraulic motor in a first direction. The hydraulic motor also is connected to the first outlet port of the third valve, which operates the hydraulic motor in a second direction.

A slewing hydraulic work machine includes a slewing control device performing a slewing control in accordance with an applied slewing command operation, a boom control device performing a boom-raising control in accordance with an applied boom-raising command operation, a boom angle detector, and a capacity control section. The capacity control section calculates a command motor capacity based on a boom angle, generates a capacity command signal corresponding to the command motor capacity and inputs the signal to a slewing motor. During the performance of slewing and boom-raising operation, the capacity control section sets the command motor capacity to a value equal to or less than a base capacity when the boom angle is equal to or less than a slewing priority angle and sets the command motor capacity to a value greater than the base capacity when the boom angle is greater than the slewing priority angle.

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.