Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B17/00—Pumps characterised by combination with, or adaptation to, specific driving engines or motors
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B53/00—Component parts, details or accessories not provided for in, or of interest apart from, groups F04B1/00 - F04B23/00 or F04B39/00 - F04B47/00
  • F04B53/16—Casings; Cylinders; Cylinder liners or heads; Fluid connections
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B17/00—Pumps characterised by combination with, or adaptation to, specific driving engines or motors
  • F04B17/03—Pumps characterised by combination with, or adaptation to, specific driving engines or motors driven by electric motors

Definitions

• This disclosure pertains to, inter alia, various types of pumps that are magnetically driven. More specifically it pertains to such pumps in which a rotary or rotary-reciprocating element, such as a pump gear, is connected to a driven magnet housed in a magnet housing ("magnet cup") in which the magnet is wetted by the fluid being pumped by the pump.
• a rotary or rotary-reciprocating element such as a pump gear
• a "sensor” usually includes a transducer or the like that converts the parameter being sensed (e.g., pressure or temperature) into a corresponding signal (e.g., an electronic or optical signal).
• the sensor usually also includes an electronic circuit that receives data directly from the transducer and processes the data for use by other electronics as required for, e.g., providing a measure of the parameter or for use in control circuits. The measurement can be used, for example, for a display of the parameter (e.g., LED display).
• An example control circuit includes a controller connected and configured to perform feedback control or other control of a motor or other actuator powering a pump.
• the pump In hydraulic systems including a pump, the pump is typically a discrete stand-alone component, by which is meant that the pump is manufactured and sold separately, from other components, to original equipment manufacturers (OEMs) for incorporation into the OEM's own system, along with other components, fluid conduits, and the like.
• OEMs original equipment manufacturers
• sensors and indicators are also usually discrete components, configured and sold for use by OEMs in any of various applications. This arrangement works fine for most hydraulic circuits, particularly those in which space is not a constraining factor.
• connecting a conventional discrete component into a hydraulic circuit typically requires some kind of static seal.
• the components can be welded into place. While usually providing an effective static seal, a component welded into place is extremely difficult or impossible to remove.
• static seal(s) are configured to allow a component to be removed from the system from time to time.
• An exemplary static seal for this purpose is an elastomeric O-ring, ring seal, gasket, or the like.
• elastomeric O-ring, ring seal, gasket, or the like is an elastomeric O-ring, ring seal, gasket, or the like.
• these and analogous types of static seals exhibit an increased probability of leaks. Leakage risk can be a serious problem in submersible systems, systems handling hazardous fluids, and systems that must operate under severe conditions or that must operate trouble-free for extremely long periods of time.
• Striving to reduce size of and/or to ruggedize a hydraulic system can substantially increase the difficulty of using certain discrete components such as pumps and sensors.
• One challenge involves the difficulty of establishing and maintaining adequate seals, such as static seals isolating the interior of a pump housing from the exterior environment or sealing around a sensor extending from outside into the hydraulic flow path.
• Another challenge arises from placing and connecting the components much closer together in the system. For example, placing a conventional stand-alone pressure sensor at the inlet or outlet of a miniaturized pump can result in a contorted arrangement that occupies too much space and in which the component is essentially shoe-horned into its location. These arrangements can excessively stress the components and/or their respective housings, compromise seals, and reduce the overall reliability and/or operational life of the components. In fact, requirements of small size and critical sealing can actually preclude the use of conventional fluidic sensors in a hydraulic system.
• Pump systems described herein were developed in the course of researching possible improvements in gear pumps used for specific applications requiring miniaturization and improved ruggedness. Specifically, including one or more sensors as part of the physical pressure barrier ("housing") of the pump provides much smaller pump-sensor combinations while mitigating the effects of any additional potential leaks by eliminating additional hydraulic connections.
• the rotary pumping member For magnetically actuating a rotary pumping member (such as a combination of a driving gear and a driven gear in a gear pump), the rotary pumping member is coupled to a driven magnet configured to rotate on a longitudinal axis when driven by a magnet driver.
• the driven magnet is sealingly housed in a magnet housing ("magnet cup") that allows the magnet to be bathed by the pumped fluid and isolated from the external environment as the magnet is being driven. This maintains the location of driven parts of the pump within the fluid path and avoids having to use a leak-prone dynamic seal.
• the ability to isolate the rotor environment from the stator environment is a primary advantage of magnetically-driven pumps.
• Adding sensors to a magnetically-driven pump generally poses a challenge regarding how to deal with electrical connections between the sensor and the electronics that either control operation of the pump (for a feedback control-type sensor), or that store and/or communicate data (for a fluid monitoring-type sensor).
• Some fluidic sensors that use wired electrical connections are designed so that the wires must pass through a hole ("through-hole") in the fluid containment wall, thus requiring a seal to prevent fluid from contacting and possibly damaging the electronics.
• through-holes and seals tends to make a pump less robust because each wire that enters a motor housing adds a potential leak point where moisture or environmental contaminants can gain access to the motor electronics.
• magnet cup eliminates the need to use discrete component(s) to provide the sensor function(s), thereby eliminating static seal(s) that otherwise would be required.
• Certain embodiments of magnet cups disclosed herein enable one or more sensors to be in indirect contact with the pumped fluid while avoiding the static seals normally required with sensors that are mounted to a fluid conduit or chamber and extend into the fluid pathway.
• the volume of space that otherwise would be occupied by housing(s) of the stand-alone component(s) is reduced, resulting in a substantially more compact assembly.
• the assemblies are made more compact and more reliable.
• the sensor electronics can be coupled directly, with minimal or no external wiring, to motor-control electronics located, for example, on a printed circuit board situated inside a housing containing a magnet-driving stator.
• pumping systems consistent with the disclosed sensing devices are not limited to gear pumps. Rather, they include any of various types of pumps having at least one movable pump element contained in a housing and coupled to a permanent magnet that is driven by magnetic forces that originate outside the housing and are directed at the magnet through walls of the housing.
• the magnet is normally contained in a portion of the housing called a magnet housing or magnet cup.
• the magnet and magnet cup are configured so that the magnet, when placed in a rotating magnetic field, rotates in the magnet cup about a longitudinal magnet axis.
• the driven magnet usually has a substantially cylindrical shape and the magnet cup has a substantially hollow cylindrical (can-like) configuration that contains the driven magnet.
• the driven magnet can be driven by a driving magnet coupled to the armature of a motor, or by a driving stator located outside the magnet cup. Lines of magnetic force produced by the driving magnet or by the stator pass through the wall of the magnet cup and inductively couple to the driven magnet. During running of the pump, these lines of magnetic force are directed so as to urge rotation of the driven magnet about its axis, which causes rotation of the rotary pump element.
• the rotary pump element is termed a "driving gear" that is interdigitated with a corresponding driven gear.
• the gear pump can be, for example, what is conventionally known as a "cavity style" or can include, for example, a “suction shoe,” or can be a hybrid of these.
• piston pump Another type of pump involving a movable pump element coupled to a driven magnet is a piston pump.
• the piston undergoes both rotary and linearly reciprocating motion as driven magnetically.
• pumps include centrifugal pumps, lobe pumps, or pumps that have a pressure-compliant member inside the housing.
• the pump housing constitutes the physical pressure barrier of the pump, i.e., the physical barrier separating the inside of the pump from its external environment (and vice versa). Escape of fluid from inside the pump housing across the physical barrier constitutes a leak.
• the pumps and hydraulic systems described herein exhibit fewer leaks under more aggressive pumping conditions, while providing improved pump performance over longer periods of time, compared to conventional pumps and systems.
• the magnet cup constitutes a portion of the pump housing
• at least one sensor is integrated into a wall of the magnetic cup so as not to be wetted by the pumped fluid.
• Such an "integral sensor” is associated with the magnetic cup in such a way that it functions essentially as a part of the cup instead of as a separate, discrete component.
• the integrated sensor os any of various sensors that can quantitatively react to their respective parameters as sensed across a wall or portion of a wall of the magnet cup, or a cross a wall or other fluid barrier coupled to a wall of the magnet cup.
• the sensor(s) can be one or more of pressure sensors, temperature sensors, or other sensors such as, for example, conductivity sensors, resistivity sensors, turbidity sensors, flow-rate (viscosity) sensors, pH sensors, dissolved gas sensors, or sensors of other fluidic variables such as turbidity, dissolved ions, and optical absorption, or sensors that detect rotation of elements of the pump motor.
• a conductivity sensor can be used, for example, to shut a pump down in the event of a "running dry" condition.
• a rotation sensor can be used, for example, if a motor controller is sensorless, to sense rotation direction or whether rotation of a pumping element is occurring at all. An example rotation sensor is based on the Hall effect.
• a dissolved gas sensor can be used to control a degassing system.
• Exemplary sensor types include strain gauge sensors, capacitive sensors, resistive sensors, piezoelectric sensors, and electrodes such as ion-specific electrodes.
• the sensors can be connected to other electronics by conventional conductors (wires, pins, and the like) or, if permitted by the type and general configuration of the sensor, by wireless connections.
• Other Hall-effect sensors detect mechanical motion of one or more internal magnetic elements.
• Inductive sensors include, for example, a voice coil for measuring acoustic signals and/or fine- positioned displacements. Another exemplary inductive sensor receives and/or transmits RF signals.
• sensors are not limited to a particular wall of the magnet cup, or even to a magnet cup at all.
• sensor(s) can be located at either the pump-inlet region of the magnet cup (for sensing, e.g., inlet pressure) or the pump-outlet region of the magnet cup (for sensing, e.g., outlet pressure).
• Exemplary mounting arrangements of the sensor to a wall of the magnet cup or other region of the pump housing, thus producing an integral sensor include direct welded, separate membrane welded, over-molded, adhesive-mounted, statically sealed in place, clamped, mechanically joined, and integrated directly into the wall by molding or casting.
• a strain-gauge based pressure sensor is capable of sensing pressure through the wall of a thin-walled magnet cup or through a localized thinner region of a magnet cup.
• Such a sensor transducer can be coupled directly to an "unpierced" wall of the magnet cup.
• a desirable method for mounting a capacitive sensor is resistance welding to a wall (e.g., the distal end wall) of a non-magnetic metal or injection-molded polymeric magnet cup.
• FIG. 1 is a coronal section of an embodiment of a magnetically-driven pump comprising a pump head and a housing.
• a sensor transducer is integrated into a wall of the magnet cup and directly connected to a circuit board.
• FIG. 2 is a coronal section of an embodiment of a compact magnetically- driven pump, comprising a pump head and a housing.
• a sensor transducer is disposed in a dry cavity within the wall of the magnet cup so as not to be wetted by the fluid being pumped.
• the integral sensor transducer may be wired directly to a nearby circuit board or it may communicate wirelessly with nearby electrical components.
• FIG. 3 is a coronal section of an embodiment of a compact magnetically- driven pump comprising a pump head and a housing.
• a sensor transducer is integrated into a wall of the magnet cup, and a dry sidewall portion of the sensor transducer is directly connected to a circuit board.
• FIG. 4 is a first perspective view of an exemplary embodiment of a magnetic cup, as used for example in the embodiment shown in FIG. 3, in which the integral sensor transducer is directly connected to an annular circuit board.
• FIG. 5 is a second perspective view of the magnetic cup shown in FIG. 4.
• FIG. 6 is a first cross-sectional view showing components at the distal end of the magnetic cup shown of FIG. 4.
• FIG. 7 is a third perspective view of the magnetic cup shown in FIG. 4, also showing the driven magnet in situ.
• FIG. 8 is a second cross-sectional view of the magnetic cup shown in FIG. 4, also showing the driven magnet in situ.
• FIG. 9 is an exploded perspective view showing coaxial components of the magnetic cup of FIG. 4.
• FIG. 10 is a first perspective view of an alternative embodiment of the magnetic cup shown in FIG. 2.
• FIG. 11 is a second perspective view of the magnetic cup shown in FIG. 10.
• FIG. 12 is a first cross-sectional view of the distal end of the magnetic cup shown in FIG. 10, in which a sensor transducer can be disposed within a dry cavity in the distal end wall of the magnetic cup and conveniently wired to a nearby printed circuit board.
• FIG. 13 is a third perspective view of the magnetic cup shown in FIG. 10, showing the driven magnet in situ.
• FIG. 14 is a second cross-sectional view of the magnetic cup shown in FIG. 10, including a sectional view of the driven magnet.
• FIG. 15 is an exploded view showing coaxial components of the magnetic cup of FIG. 13.
• FIG. 16 is a perspective view of an embodiment of the magnet cup in which sensor(s) are integrated into the side wall.
• FIG. 17 is a side elevation view of an embodiment of the magnet cup in which a sensor is integrated into the distal end of the magnet cup using a static seal.
• FIG. 18 is an exploded view of the magnet cup and sealed-sensor embodiment shown in FIG. 17.
• FIG. 19 is a block diagram showing hardware and software components of an exemplary feedback-control system that may be used to monitor and control a fluid pump.
• FIG. 1 depicts an embodiment of a pump assembly 10 including a driver portion 12 and a pump head 14.
• the pump head 14 includes an inlet port 16, an outlet port 18, a driving gear 20, a shaft 22, a driven magnet 24, and a magnet cup 26.
• the magnet cup 26 is internal to the driver portion 12.
• the magnet cup 26 has side walls 26a and a distal-end wall 26b that surround and are coaxial with the driven magnet 24.
• the side walls 26a and distal-end wall 26b serve to isolate the driven magnet 24 (which, along with the pump head 14, is generally bathed in the fluid being pumped) from electrical parts of the assembly that are kept “dry,” i.e., not wetted by the fluid being pumped.
• the fluid- wetted interiors of the pump head 1A and magnet cup 26 comprise a "pump housing.” Coaxially surrounding the magnet cup 26 is a stator 32, located outside the pump housing, that is magnetically coupled to the driven magnet 24 across the side walls 26a of the magnet cup.
• the stator 32 is contained in an enclosure 34.
• the enclosure 34 being outside the pump housing, is "dry.” In the embodiment shown in FIG. 1, the enclosure 34 and pump head 14 are mounted end-to-end so that a large part of the pump head 14 extends from the driver portion 12.
• a sensor transducer 28 comprising a parameter- sensitive surface (i.e., a surface that responds in a measurable way to the parameter to which the sensor is sensitive).
• the sensor transducer 28 is sealingly mounted with its parameter- sensitive surface facing the driven magnet 24.
• the phrase "sealingly mounted” means that the sensor transducer 28 is held in a position so as to maintain contact with at least a portion of the mounting surface at one or more contact points at which a barrier prevents fluid from passing through or across the surface.
• the barrier may take the form of, for example, the surface itself, an o-ring, an absorbent material, an adhesive material, or the like.
• the sensor transducer 28 may be a type capable of being operated while in contact with (wetted by) fluid. But, in the various embodiments discussed herein, the sensor transducer desirably also is capable of being operated (or is configured specifically for operation) in a dry condition, i.e., without being wetted by the pumped fluid. At least the parameter-sensitive surface can be incorporated into a wall of the magnet cup.
• the sensor transducer 28 in this embodiment is electrically connected directly to a printed circuit board 34 situated outside the magnet cup 28.
• the printed circuit board 30 contains an electronic circuit that, for example, receives transducer signals from the sensor transducer 28 and conditions the transducer signals for use by other electronics (not shown), such as driver electronics for the stator 32.
• FIG. 2 depicts another embodiment of a pump assembly 50 configured to occupy less space than the embodiment shown in FIG. 1.
• the pump assembly 50 comprises a driver 52 and a pump head 54.
• the pump head 54 includes an inlet port 56, an outlet port 58, a driving gear 60, a driven gear 61, a shaft 62 to which the driving gear is axially affixed, a driven magnet 64, and a magnet cup 66.
• the magnet cup 66 has side walls 66a and a distal-end wall 66b that surround and are coaxial with the driven magnet 64.
• Mounted to the distal-end wall 66b is a sensor transducer 68.
• the sensor transducer 68 is mounted such that its parameter- sensitive surface faces the interior of the magnet cup so as to sense its respective parameter through the distal-end wall 66b. Other portions of the sensor transducer 68 extend from the magnet cup 66.
• the sensor transducer 68 is electrically connected to a printed circuit board 70.
• Coaxially surrounding the magnet cup 66 is a stator 72 that is magnetically coupled to the driven magnet 64 across the side walls 66a of the magnet cup.
• the stator 72 is contained in an enclosure 74, which also contains the printed circuit board 70.
• the sensor transducer 68 can be connected to the PCB 70 by wiring (not shown).
• the sensor transducer 68 can be coupled to the PCB 70 wirelessly using, for example, radio frequency (RF) or infrared (IR) signals for delivering data to the PCB 70.
• RF radio frequency
• IR infrared
• the printed circuit board 70 desirably has not only electronics that receive and condition transducer signals from the sensor transducer 68 but also driver electronics for the stator 72.
• a portion of the pump housing is located inside a thick wall of the enclosure 74, which reduces the relative volume occupied by the pump assembly 50.
• FIG. 3 depicts another embodiment of a pump assembly 100 also configured to occupy reduced volume.
• the pump assembly 100 comprises a driver 102 and a pump head 104.
• the pump head 104 includes an inlet port 106, an outlet port 108, a driven gear 110, a driving gear 111, a shaft 112 axially coupled to the driving gear 111, a driven magnet 114, and a magnet cup 116.
• the magnet cup 116 has side walls 116a and a distal-end wall 116b that surround and are coaxial with the driven magnet 114.
• Mounted to the distal-end wall 116b is a sensor transducer 118.
• the sensor transducer 118 is mounted such that its parameter-sensitive surface faces the driven magnet 114 without being wetted by the pumped fluid normally in the magnet cup. Other portions of the sensor transducer 118 extend from the magnet cup to a first printed circuit board 120. Coaxially surrounding the magnet cup 116 is a stator 122 that is magnetically coupled to the driven magnet 114 across the side walls 116a of the magnet cup. The stator 122 is situated within an enclosure 124, which also contains the first printed circuit board 120 to which the sensor transducer 118 is mounted. The first printed circuit board 120 is connected to a second printed circuit board 126 by conductive pins 121.
• the first printed circuit board 120 contains electronics that receive and condition transducer signals from the sensor transducer 118, and the second printed circuit board 126 contains driver electronics for the stator 122.
• the pump head 104 extends at least partially into the wall of the enclosure 124, which reduces overall volume occupied by the pump assembly 100.
• the magnet cup 116 can be made of any of various rigid materials that are not magnetic.
• the magnet cup 116 can be made of a non-magnetic metal or metal alloy, in which event the magnet cup can be formed by machining, deep-drawing, casting, or the like.
• the magnet cup can be made of a polymeric or copolymeric material formed by machining or molding, for example.
• the polymeric or copolymeric material can be reinforced using fibers, particles, or other suitable non-magnetic material.
• a polymeric magnet cup may be transparent or translucent to selected wavelengths of electromagnetic radiation so as to enable a non-wetted sensor to detect, across the wall of the magnet cup, optical properties or variation in such properties of the fluid being pumped.
• FIG. 4 An exemplary embodiment of a magnet cup 150 made of metal is shown in FIG. 4, in which the depicted cup includes a cylindrical body 152.
• the body 152 includes a proximal mounting flange 154 for mounting the cup to a pump head (see FIG 3).
• the body 152 also includes a distal-end plate 156 to which a sensor transducer 158 is bonded such that the parameter- sensitive surface of the transducer faces the interior of the magnet cup.
• the opposing (outward facing) surface of the sensor transducer 158 is visible in the drawing, connected by pins 160 to an annular circuit board 162.
• the circuit board 162 includes male connector pins 164 by which the circuit board is electrically connected to other electronics located on a separate circuit board (not shown).
• FIG. 4 also shown in a different perspective view in FIG. 5, is similar to the magnet cup 26 shown in FIG. 1 and the magnet cup 116 shown in FIG. 3.
• a cross-sectional view along cut lines shown in FIG. 5 provides some additional detail, for example purposes, as shown in FIG. 6.
• Depicted in FIG. 6 are the cylindrical body 152, the distal-end plate 156 of the magnet cup 150, the sensor transducer 158, the printed circuit board 162, and connecting pins 164.
• a cover 166 configured to fit over the sensor transducer 158 and circuit board 162, with provision for the pins 164 to extend through the cover 166.
• the cup 150 shown in FIG. 4 is similar to the cup of FIG. 6, but lacks the cover 166 shown in FIG. 6.
• the cup 26 shown in FIG. 1 includes a cover, while the cup 116 shown in FIG. 3 lacks the cover.
• the sensor transducer 158 is sealingly integrated into the distal-end plate 156, such that the sensor transducer 158 remains in contact with, and surrounded by, the annular printed circuit board 162. This allows electrical signals from the sensor transducer 158 to be directly connected to hardware components on the circuit board 162 via the pins 160 (see FIG. 4) without the need for separate connecting wires and associated through-holes.
• the sensor transducer 158 is integrated with the dry side of a thin plate 156, which forms a barrier between wet and dry environments, while still allowing the sensor transducer 158 to detect one or more fluidic parameters of interest.
• the sensor transducer 158 adjacent a wet surface prevents direct contact with pumped fluid such that the sensor transducer 158 operates as a "non-wetted" sensor.
• the integration of the sensor transducer 158 with the plate 156, and the direct connection of the sensor transducer to the circuit board 162 form a mechanically rigid unit that is more likely to ensure the integrity of electrical continuity for reliable transmission of sensor data.
• FIG. 7 is another perspective view of the magnet cup 150, including the cover 166.
• a cross section of the magnet cup 150 and driven magnet 122 is shown in FIG. 8.
• FIG. 9 is an exploded view of the magnet cup 150 showing features used for making the interior of the magnet cup 150 pressure-compliant. See U.S. Patent Application Publication No. US 2009-0060728 filed on August 29, 2008, incorporated herein by reference, particularly the embodiments of pressure- absorbing members shown in FIGS. IE, 2, 3, 4A, 4B, and 5, and the accompanying discussion in paragraphs 42 - 48 and 53 - 60 of that reference. These features include a plug 168 (made of, e.g., fluorosilicone foam) and retainer 170. Also shown are the driven magnet 172 and a retainer shoe 174.
• FIG. 10 An exemplary embodiment of a magnet cup 200 made of a molded rigid polymer material is shown in FIG. 10, in which the depicted cup includes a cylindrical body 202.
• the body 202 includes a proximal mounting flange 204 for mounting the cup to a pump head (not shown).
• the body 202 also includes stiffening ribs 206 and a distal-end wall 208 in which a sensor transducer 210 is bonded such that a parameter-sensitive surface of the transducer faces the interior of the magnet cup.
• the distal-end wall 208 also includes stiffening ribs 212.
• the sensor transducer 210 comprises pins 214 by which the sensor transducer is electrically connected to a circuit board (not shown).
• the magnet cup 200 of FIG. 10 is otherwise similar to the magnet cup 66 shown in FIG. 2.
• FIGS. 11 and 12 Details of the magnet cup 200 are shown in FIGS. 11 and 12, in which a portion of the body 202 is shown along with the distal-end wall 208.
• the distal-end wall 208 defines a cavity 216 in which the sensor transducer 210 is sealingly mounted (e.g., by use of adhesive) so that the sensor transducer 210 operates as a non-wetted sensor.
• FIG. 13 shows another perspective view of the magnet cup 200, and a cross section of the magnet cup 200 is shown in FIG. 14. Further details are provided in FIG. 15, including certain features used for making the interior of the magnet cup 200 pressure-compliant. These features include a plug 218 (made of, e.g., fluorosilicone foam) and retainer 220. Also shown are the driven magnet 222 and a retainer shoe 224.
• FIG. 16 shows an alternative embodiment of a magnetic cup 230 that includes a a side wall 232, a distal-end wall 234, a proximal mounting flange 236, and an assembly 238 of one or more non-wetted sensors 240.
• the sensor assembly 238 is integrated into the side wall 232 instead of being integrated into the distal-end wall 234.
• Individual sensors 240 may be disposed in a ring around the circumference of the magnetic cup 230 such that they protrude above the surface of the cup 230.
• the sensors 240 may be configured as mini- or micro-mechanical sensors disposed within or on the surface of the body 232.
• the sensor assembly 238 may be configured as a narrow ring as shown, a wide ring, or an outer cylinder that is coaxial with side wall 232.
• FIGS. 17 and 18 show an alternative embodiment of a magnetic cup 250, that includes a side wall 252, a distal-end wall 254 that may be thicker than the side wall 252, a proximal mounting flange 256, and a non-wetted sensor 258.
• the sensor 258 may be inset into the distal-end wall 254 and held in place by a cover 260 and a seal 262.
• the seal 262 may be an adhesive, a gasket, an o-ring, or the like.
• FIG. 19 shows an exemplary feedback control system 300 for a self- modulating pump assembly that includes one or more sensing components as described above.
• the feedback control system 300 may be used to maintain a prescribed temperature or pressure associated with the pump assembly.
• all components of the control system can be located in the pump assembly without the need for additional housings, wiring, or seals.
• the exemplary software portion 302 includes an integral controller 306 and a proportional controller 308 typically used in feedback-control systems.
• the exemplary hardware portion 304 includes a digital-to-analog converter (DAC) 310, an analog-to-digital converter (ADC) 312, a motor controller (BLDC) 314 for driving the motor stator (BLDC motor) 316, and thus the pump 318, and at least one sensing component 320.
• DAC digital-to-analog converter
• ADC analog-to-digital converter
• BLDC motor controller
• a measured feedback signal 322 from the sensing component 320 is converted by the ADC 312 into a first digital feedback signal 324 that can be processed by the software portion 302. Additional data may be combined with the first digital feedback signal 324 from an external source by a second digital feedback signal 326.
• a first multiplexer 328 combines the digital feedback signals 324, 326 for processing by the controllers 306, 308.
• proportional control signal 330 and an integral control signal 332 may then be combined by a second multiplexer 334 to form a composite control signal 336.
• the composite control signal 336 may then be transmitted to the DAC 310 for conversion into an analog control signal 338.
• the analog control signal 338 may then be processed by the BLDC controller 314, and subsequently delivered at an appropriate time to the motor 316 for controlling the performance of the pump 318.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Details Of Reciprocating Pumps (AREA)
• Details And Applications Of Rotary Liquid Pumps (AREA)
• Structures Of Non-Positive Displacement Pumps (AREA)
• Permanent Magnet Type Synchronous Machine (AREA)
• Connection Of Motors, Electrical Generators, Mechanical Devices, And The Like (AREA)

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• 2011
  • 2011-06-01 US US13/151,188 patent/US20110293450A1/en not_active Abandoned
  • 2011-06-02 BR BR112012030665A patent/BR112012030665A2/pt not_active IP Right Cessation
  • 2011-06-02 KR KR1020127033978A patent/KR20140074789A/ko not_active Withdrawn
  • 2011-06-02 JP JP2013513351A patent/JP2013530669A/ja not_active Withdrawn
  • 2011-06-02 CA CA2801495A patent/CA2801495A1/en not_active Abandoned
  • 2011-06-02 EP EP11735965.3A patent/EP2417353A4/en not_active Withdrawn
  • 2011-06-02 WO PCT/US2011/038952 patent/WO2011153367A1/en not_active Ceased

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