166results about How to "Keep the flow" patented technology

A method is provided for increasing the depth of focus of an eye of a patient. A visual axis of the eye is aligned with an instrument axis of an ophthalmic instrument. The ophthalmic instrument has an aperture through which the patient may look along the instrument axis. A first reference target is imaged on the instrument axis at a first distance with respect to the eye. A second reference target is imaged on the instrument axis with the ophthalmic instrument at a second distance with respect to the eye. The second distance is greater than the first distance. Movement is provided such that the patient's eye is in a position where the images of the first and second reference targets appear to the patient's eye to be aligned. A mask comprising a pin-hole aperture having a mask axis is aligned with the instrument axis such that the mask axis and the instrument axis are substantially collinear. The mask is applied to the eye of the patient while the alignment of the mask axis and the instrument axis is maintained. Maintaining alignment of the mask axis and the instrument axis may be facilitated by capturing an image of the eye.

The present invention provides a speed governor (5) suitable for use in a fluid driven down-hole tool (3). The speed governor comprises an actuator (7) operatively coupled to a motive fluid flow control valve (6). The actuator is and arranged so as to be activatable, directly or indirectly, in response to the running speed of the tool (3), for opening of the control valve (6) with increasing rotational speed of the motor (3) above a predetermined speed limit thereby to limit the rotational speed of the downhole tool (3).

A breastshield is constructed of a low Durometer material. The breastshield includes a nipple tunnel that generally accommodates the shape of a nipple and an aperture that conveys fluids through the breastshield.

A cooling system has a diverter valve to selectively control the flow of coolant through an internal combustion engine having a cylinder block with a cooling jacket and a cylinder head mounted on the block with a cooling jacket. A controller, responsive to the temperature of the block and the head, controls the diverter valve and a water pump to provide adequate coolant flow through the head and the block as needed to maintain optimal operating temperatures. After the engine is shut off, the controller continues to operate the water pump and a cooling fan to continue to cool the engine for a period of time.

A heat transfer engine having cooling and heating modes of reversible operation, in which heat can be effectively transferred within diverse user environments for cooling, heating and dehumidification applications. The heat transfer engine of the present invention includes a rotor structure which is rotatably supported within a stator structure. The stator has primary and secondary heat exchanging chambers in thermal isolation from each other. The rotor has primary and secondary heat transferring portions within which a closed fluid flow circuit is embodied. The closed fluid flow circuit within the rotor has a spiraled fluid-return passageway extending along its rotary shaft, and is charged with a refrigerant which is automatically circulated between the primary and secondary heat transferring portions of the rotor when the rotor is rotated within an optimized angular velocity range under the control of a temperature-responsive system controller. During the cooling mode of operation, the primary heat transfer portion of the rotor carries out an evaporation function within the primary heat exchanging chamber of the stator structure, while the secondary heat transfer portion of the rotor carries out a condenser function within the secondary heat exchanging chamber of the stator. During the cooling mode of operation, a vapor-compression refrigeration process is realized by the primary heat transfer portion of the rotor performing an evaporation function within the primary heat exchanging chamber of the stator structure, while the secondary heat transfer portion of the rotor performs a condenser function within the secondary heat exchanging chamber of the stator. During the heating mode of operation, a vapor-compression refrigeration process is realized by the primary heat transfer portion of the rotor performing a condenser function within the primary heat exchanging chamber of the stator structure, while the secondary heat transfer portion of the rotor performs an evaporation function within the secondary heat exchanging chamber of the stator. By virtue of the present invention, a technically feasible heat transfer engine is provided which avoids the need for conventional external compressors, while allowing the use of environmentally safe refrigerants. Various embodiments of the heat transfer engine are disclosed, in addition to methods of manufacture and fields and applications of use.

In a method for cleaning a wafer, the wafer is placed a processing chamber. A layer or film of liquid is provided on the wafer. Electrically charged aerosol droplets of a liquid are formed and directed to the workpiece. The charged aerosol particles accumulate on the workpiece. This creates an electrical charge on the workpiece. Contaminant particles on the workpiece are released and/or repelled by the electrical charge and are carried away in the liquid layer. The liquid layer is optionally continuously replenished with fresh liquid. The liquid layer may be thinned out in a localized aerosol impingement area, via a jet of gas, to allow the electrical charge of the aerosol to better collect on or near the surface of the workpiece.

A system and method for maintaining continuous flow through a drill string during drill pipe connection includes establishing drilling fluid flow axially through the length of a tubular sub attached to the top of a drill string. The sub is then engaged with a collar disposed at least partially around the perimeter of the sub so as to define an exterior flow path along the exterior of the sub. Radial flow is then initiated into the sub through said collar and along said exterior flow path. Axial flow is then terminated through the length of the tubular sub while maintaining radial flow into the sub. A pipe joint is then attached to the top of the tubular sub, axial flow is reestablished through the length of the tubular sub, radial flow is terminated into the sub, and the collar is disengaged from the sub.

A system for pumping blood to assist or assume the cardiac function of a patient is characterized by a blood pump that exhibits a steep performance curve such that only small changes in pump flow occur for large changes in differential pressure across the pump. The pump therefore exhibits flow-limiting characteristics to protect the physiological system against harmful flow rates or pressures. Pump flow may also be limited by controlling the current provided to a driver from a power supply or by suitable restrictions within or external to the pump housing.