A portable ventilator uses a Roots-type blower as a compressor to reduce both the size and power consumption of the ventilator. Various functional aspects of the ventilator are delegated to multiple subassemblies having dedicated controllers and software that interact with a ventilator processor to provide user interface functions, exhalation control and flow control servos, and monitoring of patient status. The ventilator overcomes noise problems through the use of noise reducing pressure compensating orifices on the Roots blower housing and multiple baffling chambers. The ventilator is configured with a highly portable form factor, and may be used as a stand-alone device or as a docked device having a docking cradle with enhanced interface and monitoring capabilities.

Portable ventilator system

Control systems and methods are disclosed for processing a time series of signals associated with the movement of a device associated with a limb. The time series of motion signals is filtered, such as thorough an autoregressive filter, and compared to stored data sets representing a limb-motion event and/or phase. In certain examples, a plurality of accelerometers generate the time series of motion signals based at least on acceleration measurements in three orthogonal directions and/or planes. The acceleration measurements may relate to the movement of an artificial limb, such as a prosthetic or orthotic device. Upon determining an event and/or phase of limb motion, the control system may trigger an actuator to appropriately adjust one or more prosthetic or orthotic joints.

Systems and methods for processing limb motion

A computer controlled hydraulic resistance device for apparatus such as a prosthetic knee for above knee amputees, includes a two stage pilot operated solenoid valve connected to control the flow of hydraulic fluid to and from a hydraulic actuator which applies resistance to the prosthetic knee or other apparatus through a coupling Hydraulic pressure is sensed on the high and low side of the actuator by a spring biased magnet and a magnetically actuated electronic sensor and is used by a micro-controller in a closed-loop manner to compensate automatically for variations in the device and in the hydraulic fluid viscosity The device also has magnetically actuated electronic sensors which sense positions of the apparatus and feed back to the micro-controller for applying a predetermined resistance profile to the apparatus

Computer controlled hydraulic resistance device for a prosthesis and other apparatus

The present invention relates to a variable-torque magnetorheologically actuated prosthetic knee (110, 210) which utilizes a plurality of interspersed and alternating rotors (120, 220) and stators (130, 230) to shear magnetorheological fluid (130) in gaps formed therebetween. Advantageously, by operating in the 'shear mode' there is substantially no or negligible fluid pressure buildup or change. Moreover, the multiple MR fluid gaps or flux interfaces desirably allow for the production of a large torque at low speed without the use of a transmission and also for a wide dynamic torque range to be achieved and add to the versatility of the invention. One embodiment of the invention allows the rotors (120, 220) and/or stators (130, 230) to close the gaps therebetween to create a frictional torque component, thereby forming a 'hybrid' braking system which provides a total torque or damping which is a combination of viscous torque and frictional torque.

Electronically controlled prosthetic knee

The present invention provides a valve timing control device that can suppress a leakage of noise to the outside of the device and can improve reliability without needlessly increasing the volume occupied by the device There is provided a valve timing control device for an internal combustion engine, including a driving rotary body to which rotational force from a crankshaft is transmitted, a driven rotary body, an intermediate rotary body, a speed reduction mechanism, an electric motor, and a housing, wherein: the electric motor rotates relative to the camshaft and the housing; the valve timing control device further includes a current application switching mechanism which is provided inside the housing and which includes brushes to switch current application to a coil of the electric motor, and feeding mechanisms which are provided between the housing and an external device and which include brushes to apply a current from the external device to the current application switching mechanism; electromagnetic noise emission suppression means is provided on the power supply side of the brushes of the feeding mechanisms; and the brushes of these mechanisms are disposed apart from the rotational axis of the camshaft by substantially the same distance

Valve timing control device for internal combustion engine

The invention is a valve deactivator assembly (15) for use in connection with a valve train of an internal combustion engine. In application, a pre-selected number of the engine cylinders would each be equipped with a deactivator connected to its intake engine valve. Upon driver selection or predetermined road conditions, sufficient lost motion would be introduced into the valve train so that the valve would remain closed and the cylinder deactivated as the engine is in operation. The deactivator has in its inner body (19) a latch assembly that is in a latched condition for normal operation of the valve train. When it is desired to retain the valve in the closed position and deactivate a cylinder, the latch assembly is caused to be moved to the unlatched condition by increase in the pressure of the engine oil. When the latch assembly is unlatched, significant lost motion is introduced into the valve train causing the valve to remain closed and the cylinder is deactivated.

Hydraulically actuated latching pin valve deactivation

A dual event valve control system for an internal combustion engine. The system includes an inner rocker arm in engagement with a valve and with a first cam, an outer rocker arm in engagement with a second cam, and a latch member which is insertable between the rocker arms, whereupon when the rocker arms do not engage the latch member, the rocker arms are free to pivot independently of one another and the valve is actuated by the first rocker arm in accordance with the lift profile of the first cam, and when the rocker arms are engaged by the latch member, the rocker arms rotate in unison and the valve is actuated by the second rocker arm in accordance with the lift profile of the second cam. A stop acting between the inner and outer rocker arms limits relative pivoting movement between the rocker arms and is effective to provide clearance between the base circle portion of its second cam and the outer rocker arm.

dual event valve control system

A device for angularly displacing a camshaft (13) relative to the crankshaft of an internal combustion engine to vary engine valve timing. The device comprises a hub (17) fixed to the camshaft (13), an annular means (23) threadedly engaged with the hub (17) or with an advancing member (24) mounted on the outer surface of the annular means. Angled lugs (32) formed on a drive member coact with angled slots (35) formed on the outer periphery of the advancing member. The amount of angular displacement of the drive member (15) relative to the hub (17) and camshaft (13) is directly proportional to the axial displacement of the advancing member (24) which in turn is moved axially as the annular means (23) is moved axially along the threads (21, 22) on the hub or on the advancing member. The latter movement is effected by applying a retarding or braking torque to the annular means via the retarder means (36).

Device for varying engine valve timing

A valve control system for an internal combustion engine which does not require synchronization with the engine rotation is disclosed. The system includes an actuator having a coil electrically energized by a control unit causing a stator to magnetically attract an armature where the armature is coupled to a plunger by an actuator spring. The plunger pushes against a pivoted actuator arm having an inner and outer housing which are biased into extension by an arm spring. The actuator arm contacts and forces a slidable latch member into an inactive position and a latch spring returns the latch member into an active position. The system includes an outer rocker arm which is engageable with an engine poppet valve, and an inner rocker arm which is engageable with a cam lobe and the latch member which rotatably links and unlinks the inner and outer rocker arms. The system is adapted wherein the engine poppet valve remains closed when the inner and outer rocker arms are unlinked when the latch member is in the inactive position and wherein the engine poppet valve opens and closes in response to the cam lobe when the inner and outer rocker arms are rotatably linked when the latch member is in the active position. In an alternate embodiment, the plunger contacts a first arm of a pivoted bellcrank and a second arm contacts the latch member.

Engine valve control system using a latchable rocker arm activated by a solenoid mechanism

A magneto-rheological fluid coupling (11) including a stationary electromagnetic coil (31) and cylindrical contact member (43) surrounding an input shaft (19), and in turn, being surrounded by the output coupling assembly (15). Input (63,65) and output (29) coupling members define a viscous shear chamber (71) disposed radially outward from the coil (31). A drive member (21) extends radially from the input shaft (19) and includes an annular portion (61) at least partially surrounding the coil (31) and driving the input coupling member (63,65). The stationary coil (31) and contact member (43) eliminates the need for electrical brushes, and the problems associated therewith, and the overall arrangement of the coupling (11) results in only radial non-working air gaps, such that the efficiency and repeatability of the device is substantially improved.

Keith Hampton

Papers

Hydraulically actuated latching pin valve deactivation

dual event valve control system

Device for varying engine valve timing

Engine valve control system using a latchable rocker arm activated by a solenoid mechanism

Magneto-rheological fluid coupling