Abstract: A robotic cleaner includes a housing, a suction conduit with an opening, and a leading roller mounted in front of a brush roll. An inter-roller air passageway may be defined between the leading roller and the brush roll wherein the lower portion of the leading roller is exposed to a flow path to the suction conduit and an upper portion of the leading roller is outside of the flow path. Optionally, a combing unit includes a plurality of combing protrusions extending into the leading roller and having leading edges not aligned with a center of the leading roller. Optionally, a sealing strip is located along a rear side of the opening and along a portion of left and right sides of the opening. The underside may define side edge vacuum passageways extending from the sides of the housing partially between the leading roller and the sealing strip towards the opening.

Abstract: A hydraulic valve comprises a plurality of ports, which communicate with a passageway, and a valve member movable in the passageway to control the communication between the ports. The valve member carries a lateral shear seal which is integral with the valve member and engages the passageway. In one position, the valve member isolates a first port from a second port. In another position of the valve member, the shear seal communicates with the first port and provides communication between the first port and the second port by way of a passage within the valve member. The valve member has first and second portions of different effective cross-section areas and on each portion an integral sealing member makes a radial seal between the valve member and the passageway. A supply port supplies pressure to the outside of the valve member so as to produce by virtue of the different cross-sectional areas a force tending to move the valve member towards a closed position.

Abstract: An electrically operated hydraulic valve comprises a valve assembly that provides a common valve passageway, an inlet port, an outlet port and a return port connected to the passageway and an axially movable valve device which allows in a first position fluid flow between the outlet port and the return port while closing the inlet and in a second position, axially displaced from the first position, fluid flow between the inlet port and the outlet port while closing the return port. A spring provides a restoring force urging the valve device to its first position. An electrically operated actuator coupled to the valve device comprises a permanent magnet and a cooperating electrical coil having an associated magnetic core, one or other of the magnet and the coil constituting a stator and the other constituting an armature which is coupled to the valve device to move it from the first position to the second position.

Abstract: An electrically operated hydraulic valve comprises a valve assembly that provides a common valve passageway, an inlet port, an outlet port and a return port connected to the passageway and an axially movable valve device which allows in a first position fluid flow between the outlet port and the return port while closing the inlet and in a second position, axially displaced from the first position, fluid flow between the inlet port and the outlet port while closing the return port. A spring provides a restoring force urging the valve device to its first position. An electrically operated actuator coupled to the valve device comprises a permanent magnet and a cooperating electrical coil having an associated magnetic core, one or other of the magnet and the coil constituting a stator and the other constituting an armature which is coupled to the valve device to move it from the first position to the second position.