Abstract: The invention of the present application intends to provide a work machine that can ensure high operability by preventing abrupt actuation of an actuator and a shock to a machine body by use of a bleed-off function at the time of starting of the actuator and that can improve the energy-saving performance by reducing a bleed-off flow rate after the starting of the actuator. For this purpose, a controller opens a bleed-off valve at a timing at which an operation device is being operated and before a flow rate of a hydraulic pump starts increasing, and closes the bleed-off valve at a timing at which the operation device is being operated and after the flow rate of the hydraulic pump has started increasing.

Abstract: The present disclosure is to provide a piston assembly in which a particle does not leak out of a cylinder, and including, in an embodiment, a piston body; a piston rod connected to the piston body; a first groove formed in an outer surface of the piston body; and a particle discharge flow path extending from an internal space of the piston body to the outer surface of the piston body.

Abstract: A hydraulic apparatus has a plurality of pump modules each of which is formed by a plurality of working chambers having a common high pressure manifold. A connecting circuit switchably connects pump modules to first and second hydraulic circuit portions to allocate capacity as first and second demands for hydraulic fluid vary. In an apparatus which may have two or more connecting circuit outputs, valves may be controlled or working chamber pumping cycles made inactive to facilitate the reallocation of a pump module from one output to another, and a control strategy addresses pump module allocation when the demands for hydraulic fluid exceed available capacity.

Abstract: A brake system includes a single chamber power transmission unit, a plurality of wheel brakes, and an iso/dump control valve arrangement associated with each wheel brake of the plurality of wheel brakes. A reservoir is hydraulically connected to the single chamber power transmission unit and to each of the iso/dump control valve arrangements. A pump piston is associated with at least one wheel brake. The pump piston is driven by a second electric motor for selectively providing pressurized hydraulic fluid from the reservoir to the iso/dump control valve arrangement of the at least one associated wheel brake. First and second switching valves are provided, and are two-position, three-way type valves, each hydraulically interposed between at least one iso/dump control valve arrangement and both of a selected pump piston and the output line of the single chamber power transmission unit. First and second electronic control units are provided.

Abstract: A hydraulic system (1) for an industrial truck, in particular an electrically operated, battery-powered industrial truck, includes a lift drive (2) to raise and lower a load handling device. The hydraulic system (1) has a first hydraulic pump (5) which is configured to supply the lift drive (2) with hydraulic fluid, and a second hydraulic pump (6) which can be switched on by means of a valve device (7) for the supply of the lift drive (2). The first hydraulic pump (5) and the second hydraulic pump (6) are configured as a hydraulic double pump unit (1) and the valve device (7) is integrated into the hydraulic double pump unit (10).

Abstract: A linear drive assembly configured for use within a power end assembly. The linear drive assembly is configured to interconnect a crankshaft and a pony rod and comprises a crosshead assembly attached to a connecting rod assembly. In one or more embodiments disclosed herein, the connecting rod assembly is configured to attach to opposite sides of the crosshead assembly so that no portion of the connecting rod assembly is disposed within an interior of a crosshead included in the crosshead assembly.

Abstract: A working machine includes a prime mover, a hydraulic pump driven by power of the prime mover, a cooler including a cooling fan rotated by either the power of the prime mover or hydraulic fluid delivered from the hydraulic pump, and a controller configured or programmed to perform a reduction control for reducing a target fan rotation speed that is a target rotation speed of the cooling fan in response to reduction of an actual prime mover rotation speed that is an actual rotation speed of the prime mover, and to perform, after the reduction control, a restoration control for restoring the target fan rotation speed. The controller is configured or programmed to make a difference between a reduction rate of the target fan rotation speed in the reduction control and an increase rate of the target fan rotation speed in the restoration control.

Abstract: Provided is a work machine capable of achieving both low fuel consumption and ensuring of workability. The work machine is configured to, in a state where an output of an engine or hydraulic pump has increased to an increase threshold (S12: Yes) with the rotational speed being at a first rotational speed (S11: Yes), raise the rotational speed from the first rotational speed to a second rotational speed (S13); in a process of raising the rotational speed to the second rotational speed, output, to a regulator, a signal instructing reduction in the discharge rate (S14) so as to keep the output of the engine or hydraulic pump constant; and after the rotational speed has reached the second rotational speed, output, to the regulator, a signal instructing increase in the discharge rate (S16) so as to make the output of the engine or hydraulic pump have a value corresponding to a request load.

Abstract: Disclosed here is a system and method to control multiple eversion-based actuators using a single motor, or no motor, thereby reducing the size and cost of the multiple eversion-based actuators. An activation mechanism can include a motor rotating in an expansion direction, rotating shaft, clutch, brake, pressure source under high pressure, and/or valve. The activation mechanism can cause the actuators including a wound reel of material to unwind and lengthen. A retraction mechanism can include a motor rotating in a contraction direction opposite the expansion direction, rotating shaft, clutch, pressure source having low pressure, valve associated with the pressure source, and/or the passive retraction system. The retraction mechanism can cause the actuators to rewind and shorten.

Abstract: The invention relates to a method (19) of operating a hydraulic arrangement (1) including a mounting base (5), a boom (3) that is pivotably arranged on the mounting base (5), and a Z-kinematics (2) that is arranged on the boom (3). The Z-kinematics (2) tilts a tool attachment device (10), that is pivotably arranged on the boom (3). The boom (3) is moved by a lifting hydraulic piston (7) that is connected to the boom (3) and to the mounting base (5). The Z-kinematics (2) is moved by at least a tilting hydraulic piston (11) that is connected to a lever of the Z-kinematics (2) and to the mounting base (5). On application of an input control command for changing the position of the lifting hydraulic piston (7), a compensation command is automatically generated and applied to the tilting hydraulic piston (11), to essentially maintain the attitude of the tool attachment device (10).

Abstract: A pneumatic hydraulic retractable device includes a fluid pressure cylinder having a cylinder body and a plug seat disposed in the cylinder body, a piston rod movably disposed in the fluid pressure cylinder, a control valve set having a valve seat disposed at the piston rod and forms an upper fluid chamber and a lower fluid chamber with the cylinder body therebetween, and a valve rod disposed in the valve seat for controlling communication between the upper and lower fluid chambers, and a pressure relief element forming a pressure relief gap with the piston rod. The pressure relief gap communicates with the lower fluid chamber through a communication portion of the pressure relief element. As such, when the valve rod is opened, the fluid is allowed to flow between the lower fluid chamber and the pressure relief gap through the communication portion for reducing airtight effect.

Abstract: A hydraulic drive system for an agricultural implement includes a high pressure supply line configured to provide hydraulic fluid under pressure. The hydraulic drive system also includes a low pressure return line configured to return the hydraulic fluid. The hydraulic drive system further includes a plurality of hydraulic motors and coupled to the high pressure supply line. The hydraulic drive system still further includes a plurality of cylinder systems isolated from the high pressure supply line to minimize a supply pressure of the hydraulic fluid provided from a pump coupled to the high pressure supply line and to minimize throttling losses in the hydraulic drive system during operation of the hydraulic drive system.

Abstract: A hydraulic excavator drive system includes: a first pump connected to a head-side chamber of a boom cylinder; and a second pump that supplies hydraulic oil to at least one of an arm cylinder or a bucket cylinder. The first pump is driven by an electric motor. The drive system further includes: a first switching valve located on a rod-side line; and a second switching valve located on a relay line. The first switching valve opens the rod-side line at a boom raising operation, but blocks the rod-side line except at the boom raising operation. The second switching valve blocks the relay line at the boom raising operation, but opens the relay line at a vehicle body lifting operation.

Abstract: A displacement pump is configured to mount to a drive housing. A reciprocating drive is connectable to a pump rod of the displacement pump and includes a connecting rod and a drive link that receives a head of the pump rod. A flange projects from a pump body of the pump and a ring projects from the pump body of the pump. A portion of the drive housing is received in a gap between the flange and the ring.

Abstract: A fluid spraying system includes a displacement pump configured to mount to a drive housing. A reciprocating drive is connectable to a pump rod of the displacement pump and includes a connecting rod and a drive link that receives a head of the pump rod. A tightening ring that includes threading is configured to rotate about a cylinder of the pump and shift axially along the cylinder and engage with a bottom side of the drive housing to secure the displacement pump to the drive housing.

Abstract: A hydraulic powering system includes a hydraulic cylinder, an accumulator, and a manifold assembly. The hydraulic cylinder includes: (i) a hydraulic cylinder construction having a hydraulic cylinder wall and first and second hydraulic cylinder end caps forming an internal volume, a piston constructed to slide within the internal volume between the first and second hydraulic cylinder end caps and dividing the internal volume into an extend region and a retract region, and a piston rod extending from the piston and through the retract region and one of the first and second end caps to outside the hydraulic cylinder; (ii) an extend port in fluid connection with the extend region of the hydraulic cylinder; and (iii) a retract port in fluid communication with the retract region of the hydraulic cylinder.

Abstract: A hydraulic system includes: an arm hydraulic cylinder; a first hydraulic pump and a second hydraulic pump; an arm first direction switching valve; an arm second direction switching valve; and a controller that controls an operation of the arm second direction switching valve when the arm hydraulic cylinder is extended and operated. Further, the arm first direction switching valve incorporates an arm regeneration passage capable of supplying oil when the arm hydraulic cylinder is extended and operated, and the controller monitors a pressure state of the arm hydraulic cylinder, and when determining that oil flow through the arm regeneration passage is possible, the controller blocks oil flow between the arm hydraulic cylinder and the arm second direction switching valve, and otherwise, the controller operates the arm second direction switching valve so that oil can be supplied from the second hydraulic pump to the bottom chamber.

Abstract: A hybrid actuation device that includes a first plate coupled to a second plate, a shape memory alloy wire coupled to the first plate, and an artificial muscle positioned between the first plate and the second plate. The artificial muscle includes a housing having an electrode region and an expandable fluid region, a first electrode and a second electrode each disposed in the electrode region of the housing and a dielectric fluid disposed within the housing. The expandable fluid region of the housing is positioned apart from a perimeter of the first plate and the second plate. A first alignment aid is positioned between the first plate and the first electrode, the first alignment aid having an inner surface facing the first plate and an outer surface facing the first electrode.

Abstract: The plunger of the present disclosure includes: a plunger main body section that is made of sapphire, has a pillar shape, and includes a non-penetrating fitting hole extending in a central axis direction from one end portion; a core portion that is inserted into the fitting hole and has a higher thermal conductivity than sapphire; and a joint layer that is interposed between an inner peripheral surface and a bottom surface of the fitting hole of the plunger main body section, and an outer peripheral surface and a tip surface of the core portion, the joint layer being configured to bond the plunger main body section and the core portion. A pump includes the plunger. A liquid analysis device includes the pump.

Abstract: A system including a gearbox and a hydraulic machine connected by a working fluid circuit. The gearbox including a gearbox housing having first and second gearbox fluid passages integrated into the gearbox housing. The hydraulic machine including a case having first and second hydraulic machine fluid passages, the first and second hydraulic machine fluid passages being integrated into the case. A set of rotating elements enclosed within the case. The first gearbox fluid passage and the first hydraulic machine fluid passage align to form a feed passage to conduct fluid at a first pressure from a first source to the set of rotating elements. The second gearbox fluid passage and the second hydraulic machine fluid passage align to form a charge passage to conduct fluid at a second pressure from a second source to the set of rotating elements. The first pressure being less than the second pressure.