Abstract: Embodiments of the present invention feature a method and device for controlling the flow of fluid. One embodiment of the device for controlling the flow of fluid comprises a rotor, stator and compression means. The rotor has a rotor fluid communication means and at least one rotor load bearing surface. The rotor load bearing surface sealably engages a stationary load bearing surface. The rotor is capable of assuming a first position and a second position by rotation. The stator has a stationary load bearing surface having stator fluid communication means. The stationary load bearing surface sealably engages the rotor load bearing surface and permits rotation of the rotor with respect to the stator. At least one of the rotor bearing surface and said stator load bearing surface has a diamond-like carbon-silica coating.

Abstract: A simplified variable orifice for a conduit furnishing a stream of particulate coal to a burner for a turbine in an electrical utility plant. Two plates are installed across the conduit, one of them being fixed and the other being variable in angular position relative to the first. A lockable mechanism is provided externally of the conduit to manually adjust the degree of blocking and to indicate the position of the movable plate.

Abstract: Embodiments of the present invention are directed to devices and methods for propelling fluids that feature at least one first pump assembly having a primary pump, an accumulator pump, drive means, valve means and control means. The valve means moves between the first position and the second position as the accumulator pump and primary pump alternate between a loading movement and a pump movement. The control means is in signal communication with the accumulator pump, the primary pump and the valve means. The control means issues signal command to the accumulator pump to assume the loading movement and the pump movement and the primary pump to assume the loading movement and pump movement in coordination with the movement of the valve means such that fluids are propelled from the first outlet.

Abstract: A valve is provided that comprises a valve chamber including first and second valve port openings in communication with first and second inlet/outlets, respectively. A shaft is rotatably disposed in the valve chamber. A first valve plate is rotatably coupled to the shaft that is disposed in the valve chamber over the first valve port opening. The first valve plate has a first opening positioned so as to align with the first valve port opening. The first valve plate is configured to rotate from its closed position covering the first valve port opening to an open position, where rotation of the first valve plate adjustably positions at least a portion of the first opening over the first valve port opening. A second valve plate is configured to rotate with the first valve plate, and to cover the second valve port opening.

Abstract: A button water-stopping device has a button mechanism that can be glidingly connected to a main body, a shaking plate that can be asway set in the main body. The main body has a water channel that can penetrate the main body and a division board that is hermetically set in the water channel and has the first water hole that penetrates the division board. The button mechanism has a button and an elastic rod which is fixed under the button, and reaches into the water channel. The shaking plate has the second water hole that penetrates the shaking plate and a control groove which has two cooperative grooves. The elastic rod reaches into the control groove and can alternatively resist one of the two cooperative grooves to make the shaking plate swing left or right.

Abstract: Fluid treatment device and valve assembly therefore. The fluid treatment device comprises rotary columns or other containers which are alternately subjected to different fluid streams. In order to effect the required connection to different feed and discharge lines on the stationary part of the device, a valve assembly is proposed comprising a stationary and rotary valve plate. The front surfaces of these valve plates are directed towards each other. Optimum mating properties have been realised by producing one front surface from a plastic material and more particular a Teflon based material whilst the other front surface is produced from a polyethylene and more particular ultra high molecular weight polyethylene. This combination allows for a wide temperature range and a large number of fluids to be conveyed.

Abstract: A valve device is provided with a first block connected to an upstream-side suction tube that is connected to a negative-pressure chamber, a second block connected to a downstream-side suction tube that is connected to a pump, first and second shielding plates rotatably interposed between the first and second blocks, and servo motors for rotating the shielding plates. Each of the shielding plates has a plurality of air passing holes, and are rotated in opposite directions.

Abstract: Cooking appliance (1A,1B) having an external and control panel (2,2?) equipped with one or more regulating valves, where the rotary regulator organ (6) is equipped with various peripheral openings (16-19) for supplying a flow Q. According to two embodiments (1A, 1B) of the cooking appliance, for the supply of one or another type of gas, NG or LPG, either the control knob (9) or a bezel disk (22) in the external panel (2) are interchangeable on the appliance, being chosen between two different available units, one and the other permitting two different angular position limits A2, A3 of the regulator organ (6) for the supply of a constant flow Qmin through one or another opening (18,19) with calibrated sections, respectively for NG or LP gas. An appendix (14) in the control knob (9) guided in a slide groove (20) on the control panel (2) of the appliance, or a tongue (24) on the bezel disk stopping the rotation of the control knob, determines the travel limit A2 for the supply of Qmin of NG.

Abstract: An unfreeze faucet structure includes a watering control valve having a body; a control shaft, an upper ceramic member, and a lower ceramic member connected with the body; a valve seat locked to the body; wherein the control shaft includes a watering cavity and a positioning groove mounted in a lower section thereof, the watering cavity includes a check element and a stopping unit installed therein, the check element includes a disk-shaped cover arranged on a bottom end thereof, the cover includes a first stop loop fitted to a peripheral side thereof, between the cover and the watering cavity is defined with a spring, the stopping unit includes a trench disposed therearound to contact with the first stop loop, the control shaft includes a second stop loop fitted on an outer periphery thereof and a third stop loop arranged therearound to engage with an inner wall of the watering cavity.

Abstract: A multi-position valve assembly including a valve housing, a stator element and a rotor element rotatably mounted about a rotational axis. The valve assembly further includes a pressure adjustment assembly movable between a release position and a stop position, hard stopped relative to the valve housing. The pressure adjustment assembly includes a pressure adjuster device configured to movably cooperate between the rotor element and the valve housing to adjustably generate an axial compression pressure at the rotor-stator interface at a calibrated operating pressure, PC. When the pressure adjustment assembly is oriented in the release position, the axial compression pressure is substantially removed from the rotor-stator interface. In contrast, when the pressure adjustment assembly is oriented in the stop position, the axial compression pressure is substantially reproduced at the calibrated operating pressure, PC.

Abstract: A flow valve is provided that comprises a valve chamber including first and second valve port openings in communication with first and second inlet/outlets. The valve further includes a shaft rotatably disposed in the valve chamber, and a first valve plate rotatably coupled to the shaft that is disposed in the valve chamber over the first valve port opening. The first valve plate has a first tapered slot positioned therein so as to align with the first valve port opening. The first valve plate is configured to rotate from its closed position covering the first valve port opening to an open position, where rotation of the first valve plate adjustably positions a wider or narrower portion of the first tapered slot over the first valve port opening. The valve further includes a second valve plate that is configured to rotate with the first valve plate, and to cover the second valve port opening.

Abstract: A rotary valve comprising sliding members for supplying treatment gas containing water vapor to a plurality of treatment processes is provided. The rotary valve comprises sliding members (1, 2; 4, 6), through which open flow passages (8, 9, 10), having sliding surfaces slidable to each other and a mechanical seal mechanism for switching the flow passages (8, 9, 10) while sealing fluid by preliminarily pressing the sliding surfaces, wherein the sliding surface of each sliding members (1, 2; 4, 6) is made of hydrophobic material (2, 4) different in hardness from the other.

Abstract: A rotary metering valve arrangement comprises a rotary metering valve arranged to control the supply of fuel to a Pressure Raising and Shut-Off Valve (PRSOV), the metering valve comprising a valve plate provided with first and second latching ports and an angularly movable valve element provided with a recess registrable, in use, with the first and second latching ports to control communication therebetween, the PRSOV comprising a valve member slidable within a bore provided with third and fourth latching ports the valve member being provided with a recess registrable, in use, with the third and fourth latching ports to control communication therebetween, the second and third latching ports communicating with one another.

Abstract: An air driven diaphragm pump includes an performance control actuator having a housing with opposed air chambers. The pump includes pump chambers facing the air chambers and pump diaphragms extending between each air chamber and each pump chamber, respectively. The actuator further includes an air valve, an intake to the air valve and an engagement. The intake includes an intake passage and a performance control intake adjuster rotatably mounted. The intake adjuster has a helical channel and a closure element extending adjustably into the intake passage. The engagement engages the helical channel for control of the intake. The helical channel has varied pitch to provide a nonlinear relationship between rotation and axial advancement of the intake adjuster. The nonlinear relationship gives flow rate proportional to the angular rotation of the intake adjuster.

Abstract: A pulse width modulated fluidic valve 3005 includes a cylinder (352) having an elongate bore, a length, and first (344) and second (346) ports which extend from outside the cylinder (352) into the bore. A rotatable spool (302) is carried in the bore and movable in a direction of the length of cylinder (352). The spool (302) has a variable blocking feature (306) which blocks passage of fluid between the first (344) and second (346) ports as a function of angular position relative to the first (344) and second (346) ports and as a function of linear position along the length of the cylinder (352).

Abstract: A device for adjusting the flow-rate of a fluid, particularly medical oxygen and compressed gases in general, which comprises a valve body which defines an input duct for a low-pressure fluid which is connected to a rotary flow control element, which has an output port which can be arranged at the calibrated holes of a flow-rate adjustment disk; the calibrated holes are connected to an output duct; an actuation handwheel is also provided which is functionally associated with the rotary flow control element; the actuation handwheel comprises means for positioning the flow control element so that the output port is arranged at at least one of the calibrated holes.

Abstract: Described is an automatic dispensing apparatus for dispensing toothpaste. The dispensing apparatus comprises a housing having a front portion with a hole therethrough. The housing is capable of holding a tube of toothpaste. A sensor is attached with the housing. A spring is connectable with the housing for compressing the container of the viscous substance. A dispenser head is attached with the housing for attaching with the container of the viscous substance. Additionally, a motor is connected with the sensor and the dispenser head. Thus, a user can activate the sensor by placing an object proximate the sensor to activate the motor so that the motor rotates the dispenser head. In operation, the spring compresses the tube of toothpaste such that the toothpaste is pressed out of the container and through the dispenser head and the hole in the front portion of the housing to be dispensed upon a toothbrush.

Abstract: A butterfly valve comprises a valve shaft placed across a flow passage and a plate-like valve element provided on the valve shaft so as to be rotatable about the valve shaft to regulate a flow rate of fluid in the flow passage. The valve element has a section that gradually decreases in thickness from the valve shaft toward an outer edge in a direction nearly perpendicular to the valve shaft. The valve element further includes a plurality of inclined surfaces on each side so that the corresponding inclined surfaces on both sides of the valve element are identical in section in a direction parallel to the valve shaft. The valve element is provided on each side with a plurality of flow straightening ribs each extending in a direction perpendicular to the valve shaft and inclining along each inclined surface.

Abstract: A valve comprises a housing and at least three ceramic discs in the housing such that at least two fixed ceramic discs are provided and at least one rotatable ceramic disc is provided between the fixed ceramic discs. The ceramic discs comprise through holes such that when the holes are aligned, the valve is open, and turning the rotatable ceramic disc turns the holes to be misaligned in successive ceramic discs, which prevents water flow through the valve. The valve further comprises a handle for rotating a rotatable ceramic disc and the handle comprises a stem extending through the housing, and a curved part, the curved part curving at least partly around the housing along the circumference of the housing.

Abstract: A rotary valve unit is provided for blending fluid sources to regulate a temperature of fluid flowing to a heat exchange device in an extracorporeal blood perfusion circuit. A valve body includes a valve chamber having a first inlet port, a second inlet port, a first outlet port, and a second outlet port. A wedged-shaped rotary valve is disposed within the valve chamber and is rotatable within the valve chamber for controlling a blending of the cold fluid entering the fluid chamber from the first inlet port and the return fluid entering the fluid chamber from the second inlet port to regulate the desired temperature of fluid provided to the heat exchanger. The wedge-shaped rotary valve is positionable to provide either only cold fluid to the first outlet port, only return fluid to the first outlet port, or blending of the cold fluid and return fluid to the first outlet port.

Abstract: A distal rate control device, which can be conveniently interposed between a fluid supply line and fluid delivery line for precisely controlling the rate of fluid flow toward the delivery line. The device includes a readily adjustable flow rate control device having a novel flow control plate that can be placed in fluid communication with the fluid supply line and with the fluid delivery line. The flow control plate is provided with a plurality of elongated fluidic flow control channels that are in communication with a rate selector member that is rotatably carried by the device housing. Rotation of the rate selector member places a selected one of the flow control channels in communication with the fluid delivery line.

Abstract: The present invention provides a pneumatic tool enabling sectional adjustment of torsional force, including a main body and a cylinder mounted into the accommodation space of main body. The cylinder is fitted with air vents and also a rotor. A plurality of exhaust holes is arranged at one side of the cylinder tube of the cylinder. An exhaust duct switching member is arranged between the exhaust holes of the cylinder tube and air exhaust duct of the main body and used to switch the airflow for air exhaust by different exhaust holes. The pneumatic tool enables sectional adjustment of its torsional force, thus promoting the torsional force efficiently with better applicability.

Abstract: A rotary selection valve where different components can be selected in different rotation positions of the valve and furthermore the flow through the components can be reversed by rotating the rotary valve.

Abstract: Cooking appliance (1A,1B) having an external and control panel (2,2?) equipped with one or more regulating valves, where the rotary regulator organ (6) is equipped with various peripheral openings (16-19) for supplying a flow Q. According to two embodiments (1A, 1B) of the cooking appliance, for the supply of one or another type of gas, NG or LPG, either the control knob (9) or a bezel disk (22) in the external panel (2) are interchangeable on the appliance, being chosen between two different available units, one and the other permitting two different angular position limits A2, A3 of the regulator organ (6) for the supply of a constant flow Qmin through one or another opening (18,19) with calibrated sections, respectively for NG or LP gas. An appendix (14) in the control knob (9) guided in a slide groove (20) on the control panel (2) of the appliance, or a tongue (24) on the bezel disk stopping the rotation of the control knob, determines the travel limit A2 for the supply of Qmin of NG.

Abstract: The cooking appliance (1) having a control panel (2) is equipped with one or more gas flow (Q) regulating valves, wherein the rotary regulating plug (6) is provided with various peripheral through holes (16-19). The control knob (9) being interchangeable for fitting to the actuating shaft (7), is chosen from the two units available, one and the other permitting different angular limit positions of the regulating plug (6) for the supply of a constant minimum gas flow Qmin, adjusted each one for a different type of gas N gas or LP gas. The outlet conduit (5) of the valve is equipped with a further injector nozzle (21,23) for adjusting a constant gas flow Qmax to be fed into the conduit (25) of the correspondent burner, when the cooking appliance is supplied with a LP gas.

Abstract: A flow control valve is provided that comprises a valve housing having an inlet, an outlet, and a valve chamber that includes a first valve port opening in communication with the inlet and a second valve port opening in communication with the outlet. The various embodiments further comprise a modulating member having first and second tapered arcuate slots therein, which is disposed in the valve chamber approximate the first valve port opening and second valve port opening. The modulating member is rotatable to adjustably position a wider or narrower portion of both the first tapered arcuate slot and second tapered arcuate slot over the first valve port opening and second valve port opening respectively, to adjustably vary the rate of fluid flow through the valve.

Abstract: A flow regulator for medical liquids comprising a first body and a second body coupled to one another in a rotatable way and a gasket set between them and overmolded on the second body. Provided thereon is at least one graduated scale formed by impressions and/or, respectively, by reliefs integral with the second body, and by inserts and/or, respectively, by complementary openings of a side skirt of the overmolded gasket.

Abstract: The present invention provides a rotary valve structure, which has a rotary water passage structure including a switching component and fixed hole. A first water-guide portion and second water-guide portion are placed laterally onto the switching component, whilst a first punch hole and second punch hole are placed separately onto the fixed hole. A coupling portion is placed between the first water-guide portion and second water-guide portion of the switching component. When the first water-guide portion and second water-guide portion of the switching component are placed opposite to the first punch hole and second punch hole of the fixed hole respectively, the first punch hole and second punch hole form a through-flow structure that prevents water from contacting the metal portions of the housing.

Abstract: A valve assembly has a valve housing, an inlet, an outlet and a flow passage extending between the inlet and the outlet. A shut-off valve is mounted on the housing adjacent the inlet and a flow control valve is mounted on the housing adjacent the outlet. By mounting both valves on the same housing, the dimensions of the assembly are reduced.

Abstract: A bi-directional metering valve assembly is provided to selectively direct hydraulic fluid under high pressure to a load. The assembly includes a valve block defining a first port that receives hydraulic fluid from a source, and a second port that directs hydraulic fluid toward a load. A rotatable valve member defines first and second apertures in an axial face that may be placed in selective communication with the first and second ports, respectively, to direct hydraulic fluid from the source to the load. At least one metering sealing assembly provides an interface between the valve block and the valve member. The metering sealing assembly includes a gasket that surrounds one of the first and second ports and defines a flange that is sized to completely overlap and seal the corresponding aperture. The valve member is operable to control the direction of fluid flow, and make fine adjustments to the hydraulic fluid flow rate.

Abstract: A flow control valve is provided that comprises a valve housing having an inlet, an outlet, and a valve chamber that includes a first valve port opening in communication with the inlet and a second valve port opening in communication with the outlet. The various embodiments further comprise a modulating member having first and second tapered arcuate slots therein, which is disposed in the valve chamber approximate the first valve port opening and second valve port opening. The modulating member is rotatable to adjustably position a wider or narrower portion of both the first tapered arcuate slot and second tapered arcuate slot over the first valve port opening and second valve port opening respectively, to adjustably vary the rate of fluid flow through the valve.

Abstract: A fluid discharge apparatus adapted to discharge a cavitating stream of pressurized liquid along with the selective discharge of a secondary material, such as an abrasive, for removing dirt, debris, barnacles, marine growth, and other substances from submerged surfaces is provided. More particularly, the invention contemplates a introducing a pressurized liquid into a cavitation generating chamber to create and discharge a cavitating stream, and a secondary inlet for injecting abrasive material, such as silica, into the chamber to improve cleaning effectiveness. The gas bubbles within the cavitating liquid stream that essentially explode upon impacting debris resulting in tremendous pressure fluxuations provides improved effectiveness in removing debris and aquatic growth from the submerged surface. The combination of a secondary substance, such as an abrasive material, foam, or compressed gas enhances cleaning effectiveness.

Abstract: A butterfly valve having a pair of disk tails provided at the back of a valve body in the rotation direction in an opening operation, a water flow hole formed in each disk tails, and a steady region found in relationship between loss factor and opening degree of the valve body where the loss factor becomes substantially constant with a change in opening degree of the valve body when water is filled from the water flow hole. Water filling velocity in an upstream pipe of the butterfly valve from the water flow hole, and pressure head upstream of the butterfly valve are set. Optimal value of the loss factor is determined based on the set water filling velocity and pressure head, and a total opening area of the water flow holes is set so that the loss factor equals the optimal value in the steady region.

Abstract: A control disk for a fluid valve has a disk body having at least one through hole, the body having an upper surface for contacting another control element of the valve and an opposed lower surface. The upper surface is formed with a raised undulating contact surface. The raised undulating contact surface defines pockets suitable for receiving a lubricant.

Abstract: An orifice for use in a flow control valve, the orifice may include a fixed choke plate having at least one aperture therethrough for conducting fluids and a rotating choke plate having at least one aperture therethrough for conducting fluids. The rotating choke plate may be concentric with and disposed face-to-face with the fixed choke plate. Each of the apertures in the fixed choke plate and rotating choke plate include a rounded head section and a crescent tail section. Rotation of the rotating choke plate relative to the fixed choke plate varies an alignment of the fixed choke plate aperture and the rotating choke plate aperture.

Abstract: An apparatus and method are provided for replacing existing actuator driven zone valves in an HVAC system, and particularly valves of the rubber paddle type having actuators providing less than 90 degrees of rotation, with a ball valve including a skewed seat bearing that blocks flow through the flowpath when a valve member of the ball valve is rotated through an angle of substantially less than 90 degrees from a fully open position of the valve at which a bore in the valve member is substantially fully aligned with the flowpath. The actuator from the existing zone valve being replaced may be used with the provided ball valve apparatus and method.

Abstract: The present invention provides a rotary valve structure, which has a rotary water passage structure including a switching component and fixed hole. A first water-guide portion and second water-guide portion are placed laterally onto the switching component, whilst a first punch hole and second punch hole are placed separately onto the fixed hole. A coupling portion is placed between the first water-guide portion and second water-guide portion of the switching component. When the first water-guide portion and second water-guide portion of the switching component are placed opposite to the first punch hole and second punch hole of the fixed hole respectively, the first punch hole and second punch hole form a through-flow structure that prevents water from contacting the metal portions of the housing.

Abstract: A rotation speed regulating mechanism for pneumatic tools includes a movable airflow knob coupled on the periphery of an air intake member through screw threads. The airflow knob can be turned to adjust the size of an air inlet of the air intake member in a stepless fashion to regulate airflow entering an pneumatic tool so that the rotation speed of the pneumatic tool may be regulated in a stepless manner. Use of the pneumatic tool is more effective and convenient.

Abstract: A rotary metering valve arrangement comprises a rotary metering valve arranged to control the supply of fuel to a Pressure Raising and Shut-Off Valve (PRSOV), the metering valve comprising a valve plate provided with first and second latching ports and an angularly movable valve element provided with a recess registrable, in use, with the first and second latching ports to control communication therebetween, the PRSOV comprising a valve member slidable within a bore provided with third and fourth latching ports the valve member being provided with a recess registrable, in use, with the third and fourth latching ports to control communication therebetween, the second and third latching ports communicating with one another.

Abstract: A valve cartridge includes a housing having a bore. A fixed control disc and a rotatable control disc are provided in the bore. A shaft extends through the bore, and rotation of the shaft serves to rotate the rotatable control disc relative to the fixed control disc. The shaft is seated in said bore using at least one bushing. The at least one bushing serves in spacing the shaft from the housing, and provides for the smooth rotation of the shaft relative to the housing.

Abstract: The electric control valve, in which a throttled flow rate is quantitatively determined by the groove 16 by a rotating position of the valve body 20, the valve seat surface projects like a band from a border band 16C drawing an outline of the groove 16, and the end surface of the valve body 20 contacts slidingly on a top surface of the border band 16C.

Abstract: A device (10) and method for aseptically or non-aseptically accessing a fluid in a container (210) using an existing container opening (211). The device (10) includes a sanitary fitting (12) for attaching the device to the container over the existing container opening, and a sample coupling (14) associated with the sanitary fitting. The sanitary fitting (12) includes a first port (32), and the sample coupling (14) includes at least two second ports (52). The sample coupling (14) is rotatable relative to the sanitary fitting (12) in one direction to cause the first port (32) to successively align with each of the second ports (52), and thereby allows access to the fluid through the aligned first and second ports (32,52).

Abstract: An air passage 2 is provided with an air passage groove 5 that supplies a required volume of air to the side downstream from the fully closed position of a valve body for control purposes. Further, a taper is formed in such a way that a predetermined volume of air can be supplied, even if positional variations have occurred to the valve body. This arrangement allows the volume of air required for the traveling of a car to be supplied, without increasing the number of parts, even if the valve body 3 has stuck downstream from the controlled area. This arrangement also permits a stable supply of air flow at the idle position of the valve body.

Abstract: A valve assembly including a downwardly directed funnel, a substantially cylindrical body position within a cylindrical base and a cylindrical valve within the cylindrical body atop of the funnel includes a baffle, a latch and a planar semi-circular surface about which the cylindrical valve adapted to rotate to open and close the valve.

Abstract: In a direct injection type automatic sampler, a sampling needle having a liquid sample collected from a sample vessel by using suction force of a pump is inserted into an injection port. Then, a flow path-switching valve is rotated to switch a flow path to make a flow of mobile phase liquid pass through a loop to thereby introduce the collected sample into a column. The injection port is directly incorporated in the flow path-switching valve.

Abstract: A suction limiting device with variable control for use in a surgical system includes a main vent body having a fluid carrying bore extending therethrough and a variable vent mechanism having a main vent opening in selective fluid communication with the fluid carrying bore so as to permit introduction of atmospheric air into the fluid carrying bore. The vent mechanism being adjustable so that the degree of airflow into the fluid carrying bore is variable between a fully open position to a fully closed position where atmospheric air is prevented from entering the fluid carrying bore. The suction limiting device also includes a valve disposed within the main vent body and positionable between an open position when negative pressure and a closed position when positive pressure exists in the main vent body.

Abstract: The invention is intended to simplify a default mechanism of a throttle valve opening and closing device for the purpose of improving mountability of the device to a vehicle. When a motor generate no driving forces, a throttle valve is held in a position (1) by a return spring. In this position, gaps are formed between the throttle valve and a wall surface of an intake passage. Spherical recesses are formed in parts of the wall surface of the intake passage. In a position (2) where the throttle valve is opposed to the spherical recesses, the gaps are minimized in an operating range of the throttle valve.

Abstract: A cock has an indexable rotating key. Indexing is achieved by a raised element on a shaped base of a housing of a barrel, and a ring which is formed at the end of the key and which is elastically deformable in a transverse plane. The raised element and ring form stubs and notches which cooperate to determine key blocking positions when the key is being rotated. The cock is suitable for use with medical instruments.

Abstract: A covering device for a drain includes a first cover and a second cover. The first cover defines a plurality of openings. The second cover defines a plurality of openings corresponding to the openings of the first cover. The second cover is rotationally connected to the first cover. In a position, the openings of the second cover are aligned with the openings of the first cover in order to open the drain. In another position, the first cover blocks the openings of the second cover while the second cover blocks the openings of the first cover in order to close the drain.

Abstract: A method for controlling fluid flow. A fluid (560) can be communicated to a first fluid flow port (105) disposed adjacent to a first surface (196) of a rotatable disk (115) of a homopolar motor. The fluid can flow through at least one orifice (130) in the rotatable disk to a second fluid flow port (110). The rotation of the disk can be selectively controlled to vary a fluid flow rate. Further, the disk can be rotated to align a selected one of the orifices with at least one of the first and second fluid flow ports. In another arrangement, the shape of the orifice can have a radial width that increases in a circumferential direction.