Abstract: A pumping device compresses fluid, provides a vacuum, or both compresses fluid and provides a vacuum. A pumping device may be used to force gas through a sieve bed, draw gas out of a sieve bed, or both force gas through a sieve bed and drawing gas out of a sieve bed. A pumping device may be operated at high speed to provide a high fluid flow rate with a small pumping device.

Abstract: Embodiments of oxygen concentrators having a sieve bed that includes a vessel containing a separation medium are disclosed. In one embodiment, the sieve bed vessel attaches to a chassis component using a press-fit configuration to lock and seal the sieve bed vessel to a chassis component.

Abstract: Embodiments of oxygen concentrators having a sieve bed that includes a vessel containing a separation medium are disclosed. In one embodiment, the sieve bed vessel attaches to a chassis component using a press-fit configuration to lock and seal the sieve bed vessel to a chassis component.

Abstract: A wheelchair suspension comprises a frame, at least one pivot arm, at least one front caster, at least one rear caster, a stabilizing system, and a sensor. The pivot arm is coupled to the frame. The front caster is coupled to the pivot arm. The rear caster is coupled to the frame. The stabilizing system is coupled to the frame and the pivot arm. The sensor is arranged such that movement of the frame relative to the rear castor causes actuation of the stabilizing system to at least partially resist further movement of the frame.

Abstract: A pumping device compresses fluid, provides a vacuum, or both compresses fluid and provides a vacuum. A pumping device may be used to force gas through a sieve bed, draw gas out of a sieve bed, or both force gas through a sieve bed and drawing gas out of a sieve bed. A pumping device may be operated at high speed to provide a high fluid flow rate with a small pumping device.

Abstract: A wheelchair suspension comprises a frame, at least one pivot arm, at least one front caster, at least one rear caster, a stabilizing system, and a sensor. The pivot arm is coupled to the frame. The front caster is coupled to the pivot arm. The rear caster is coupled to the frame. The stabilizing system is coupled to the frame and the pivot arm. The sensor is arranged such that tipping of the frame causes actuation of the stabilizing system to at least partially resist further movement of the frame.

Abstract: A wheelchair suspension is provided. The wheelchair suspension includes a frame, a front caster pivot arm, a drive assembly, and a rear caster. The front caster pivot arm is pivotally connected to the frame. The front caster is coupled to a front end of the front caster pivot arm. The drive assembly is pivotally connected to the front caster pivot arm. The drive assembly comprises a drive wheel and a motor that drives the drive wheel. Torquing of the drive wheel by the motor in a forward direction causes the drive assembly to pivot with respect to the front caster pivot arm such that the drive wheel moves forward toward the front caster and a distance between a support surface and the connection between of the drive assembly and the front caster pivot arm increases.

Abstract: A wheelchair suspension is provided. The wheelchair suspension includes a frame, a pivot arm, a front caster, a drive assembly, and a rear caster. The pivot arm is pivotally coupled to the frame. The front caster is coupled to the pivot arm. Movement of the drive assembly in a first direction causes the pivot arm to substantially remain in a first position. Movement of the drive assembly in a second direction urges the pivot arm away from the first position.

Abstract: A home care oxygen system includes an inline compressor that has all the check valves and gas flow passages between cylinders located in the cylinder head. Only a single check valve is used for each cylinder. The crankshaft is built up from a shaft with eccentrics and spacers.

Abstract: A compressor includes a cylinder assembly in a V4 configuration. A crankshaft of the compressor has a main shaft and first and second eccentric bodies. The two eccentric bodies drive four pistons.

Abstract: A wheelchair suspension is provided. The wheelchair suspension includes a frame, a pivot arm, a front caster, a drive assembly, and a rear caster. The pivot arm is pivotally coupled to the frame. The front caster is coupled to the pivot arm. Movement of the drive assembly in a first direction causes the pivot arm to substantially remain in a first position. Movement of the drive assembly in a second direction urges the pivot arm away from the first position.

Abstract: A wheelchair suspension is provided. The wheelchair suspension includes a frame, a pivot arm, a front caster, a drive assembly, and a rear caster. The pivot arm is pivotally coupled to the frame. The front caster is coupled to the pivot arm. Movement of the drive assembly in a first direction causes the pivot arm to substantially remain in a first position. Movement of the drive assembly in a second direction urges the pivot arm away from the first position.

Abstract: A wheelchair includes at least one side frame connected to a front caster assembly, and a cross-brace assembly. The cross-brace assembly includes a cross-brace member; at least one rear caster assembly connected to the cross-brace member; at least one main drive wheel axle tube fitting connected to the cross-brace member; and at least one arm connected to the cross-brace member. The at least one arm is pivotally connected to the at least one side frame through a pivot joint.

Abstract: A suspension for a vehicle is provided. The suspension includes, for example, a frame and a releasable locking assembly. The releasable locking assembly has, for example, a first assembly movably coupled to the frame, a second assembly movably coupled to the frame, and wherein movement of the frame relative to the first and second assemblies causes the first and second assemblies to engage each other to limit further movement of the frame in at least a first direction.

Abstract: The present invention provides a curb-climbing wheelchair having pivotal arm assemblies. The pivotal arm assemblies include at least one front caster and have the ability to rotate or pivot. The pivot arms rotate or pivot in response to moments generated by accelerating or decelerating the wheelchair thereby raising or lowering the front caster(s) through the rotational movement of the pivot arms. By raising or lowering the front caster(s) in such a manner, curb-like obstacles can be traversed in a low-impact manner.

Abstract: A suspension for a vehicle is provided. The suspension includes, for example, a frame and a releasable locking assembly. The releasable locking assembly has, for example, a first assembly movably coupled to the frame, a second assembly movably coupled to the frame, and wherein movement of the frame relative to the first and second assemblies causes the first and second assemblies to engage each other to limit further movement of the frame in at least a first direction.

Abstract: The present invention provides a curb-climbing wheelchair having pivotal arm assemblies. The pivotal arm assemblies include at least one front caster and have the ability to rotate or pivot. The pivot arms rotate or pivot in response to moments generated by accelerating or decelerating the wheelchair thereby raising or lowering the front caster(s) through the rotational movement of the pivot arms. By raising or lowering the front caster(s) in such a manner, curb-like obstacles can be traversed in a low-impact manner.

Abstract: The present invention provides a curb-climbing wheelchair having pivotal arm assemblies. The pivotal arm assemblies include at least one front caster and have the ability to rotate or pivot. The pivot arms rotate or pivot in response to moments generated by accelerating or decelerating the wheelchair thereby raising or lowering the front caster(s) through the rotational movement of the pivot arms. By raising or lowering the front caster(s) in such a manner, curb-like obstacles can be traversed in a low-impact manner.

Abstract: A suspension for a vehicle is provided. The suspension includes, for example, a frame and a releasable locking assembly. The releasable locking assembly has, for example, a first assembly movably coupled to the frame, a second assembly movably coupled to the frame, and wherein movement of the frame relative to the first and second assemblies causes the first and second assemblies to engage each other to limit further movement of the frame in at least a first direction.

Abstract: A curb-climbing wheelchair having pivotal arm assemblies. The pivotal arm assemblies include at least one front caster and have the ability to rotate or pivot. The pivot arms rotate or pivot in response to moments generated by accelerating or decelerating the wheelchair thereby raising or lowering the front caster(s) through the rotational movement of the pivot arms. By raising or lowering the front caster(s) in such a manner, curb-like obstacles can be traversed in a low-impact manner.