The invention relates to a fuel-operated firing device for driving securing elements into a substrate, comprising at least one main combustion chamber for a fuel, a driving piston that can be driven out of the main combustion chamber in a firing direction by expandable gases, and a pre-chamber with which an ignition device is associated and in which a pressure acting on the main combustion chamber can build up prior to a fuel-air mixture being ignited in said main combustion chamber. In order to improve the efficacy and/or functionality during the driving in of securing elements using the fuel-operated firing device, the pre-chamber has at least two venting connections which are mutually spaced in an axial direction and which have passages that can be exposed conjointly in order to facilitate rapid venting of the pre-chamber.

A first on-off valve (2) and a second on-off valve (3) each are a two-port valve. A first passage block (5) is provided with a first on-off valve-corresponding inflow passage (11) and a first on-off valve-corresponding outflow passage (12). A second passage block (6) is provided with a second on-off valve-corresponding inflow passage (14) and a second on-off valve-corresponding outflow passage (15). The second on-off valve-corresponding outflow passage (15) is in communication with an upstream side portion of the first on-off valve-corresponding outflow passage (12) via a communicating passage (13) formed in the first passage block (5). An orifice (20) is provided between the second on-off valve-corresponding outflow passage (15) and the communicating passage (13).

An example apparatus includes: a plate configured to move along an underlying surface via a layer of fluid disposed in a gap between the plate and the underlying surface, where pressurized fluid forms the layer of fluid in the gap; a first rack gear coupled to the plate and meshing with a first gear; and a second rack gear coupled to a second gear. The second rack gear is fixed, and the second gear is coupled to the first gear. The pressurized fluid in the gap repels the plate away from the underlying surface, thereby causing (i) the first rack gear to move linearly and the first gear to rotate, (ii) the second gear to rotate and move along the second rack gear, and (iii) the plate to move along the underlying surface.

An actuator is disclosed comprising: a moveable member; a first hydraulic chamber in contact with a first surface of the moveable member; a second hydraulic chamber in contact with a second, opposing surface of the moveable member; a movable locking mechanism coupled to a moveable wall of the second hydraulic chamber; and a resilient biasing member acting on the moveable wall of the second hydraulic chamber so as to bias the moveable wall and locking mechanism. The actuator is configured to selectively vary the pressure in the second hydraulic chamber so that the resilient biasing member is able to bias the moveable wall to move, thereby moving the locking mechanism to engage the moveable member so as to prevent the movement of the moveable member towards at least one of the first and second hydraulic chambers.

The present disclosure envisages a unitary housing for housing hydraulic components, wherein the hydraulic components are configured for operating a hitch mechanism of a tractor. The unitary housing comprises cavities for locating valve mechanisms therein and a cylinder for accommodating a reciprocating piston. The unitary housing together with a plurality of valve mechanisms disposed in corresponding cavities, forms a predetermined hydraulic circuit. The hydraulic circuit has minimum number of leakage joints, minimizes number of components and therefore assembly and machining operations.

A hydraulic system includes a hydraulic pump to output an operation fluid, a hydraulic apparatus to be activated by the operation fluid, an operating member to operate the hydraulic apparatus, an operation valve to determine a pressure of the operation fluid in accordance with operation of the operating member, the operation fluid being supplied to the hydraulic apparatus, a first fluid tube connecting the hydraulic pump to the operation valve, a first working valve disposed on the first fluid tube, the first working valve being configured to change an opening aperture of the first working valve, a first outputting fluid tube connected to a section of the first fluid tube between the operation valve and the first working valve, and a second working valve disposed on the first outputting fluid tube, the second working valve being configured to change an opening aperture of the second working valve.

An actuator includes a base to which first and second fluid couplings are fixed, a rotation member rotatably supported by the base, and McKibben-type first and second artificial muscles wound around the rotation member. The first and second artificial muscles are arranged in an antagonistic manner. One ends of the first and second artificial muscles are fixed to the rotation member. The other ends of the first and second artificial muscles are respectively connected to the first and second fluid couplings.

A spacer assembly for restricting actuation of a hydraulic cylinder. The spacer assembly comprises a support bracket configured to be secured to the hydraulic cylinder. The spacer assembly additionally comprises a plurality of shims supported by the support bracket, whereby each of the shims is configured to be shifted between an unengaged position and an engaged position. When the shims are in the engaged position the shims are configured to restrict actuation of the hydraulic cylinder. The spacer assembly further comprises a shifting assembly configured to permit a group of at least two shims to be simultaneously shifted between the unengaged position and the engaged position.

A piston's stroke length may be restricted by passing a rod through a through hole in the piston. The stroke length's boundaries may be defined by the points where an interior of the through hole contacts an exterior of the rod. Adjusting a position or orientation of the rod may alter this stroke length. If the rod comprises a noncylindrical external geometry, a radius thereof may vary along an axial length of the rod or around a circumference thereof. Adjustment of the rod, via axial translation or rotation for example, may change the position of contact between the rod and the through hole. Alternately, the through hole may comprise a unique geometry in which the rod may radially translate to adjust the piston's stroke length.

A rotary actuator and a method of additively manufacturing the same are provided. The rotary actuator includes a valve housing defining a valve chamber and a shaft channel extending from the valve chamber. A valve body includes a valve shaft extending through the shaft channel and a valve head positioned within the valve chamber and defining a head width that is larger than the channel diameter to inseparably join the valve body and the valve housing. The valve head divides the valve chamber into a first chamber and a second chamber which are in fluid communication with a first port and a second port, respectively. The valve body is rotated by adjusting a fluid pressure within at least one of the first chamber and the second chamber.