7696 results about "Fluid pressure" patented technology

A method of treating cardiovascular disease in a medical patient is provided. The method includes the steps of generating a sensor signal indicative of a fluid pressure within the left atrium of the patient's heart, and delivering an electrical stimulus to a location in the heart. The electrical stimulus is delivered based at least in part on the sensor signal. The method also includes the steps of generating a proccessor output indicative of a treatment to a signaling device. The processor output is based at least in part on the sensor signal. At least two treatment signals are provided to the medical patient. The treatment signals are distinguishable from one another by the patient, and are indicative of a therapeutic treatment. The treatment signals are based at least in part on the processor output.

A downhole tool that functions as an underreamer, or alternatively, as a stabilizer in an underreamed borehole. The tool includes one or more moveable arms disposed within a body having a flowbore therethrough in fluid communication with the wellbore annulus. The tool alternates between collapsed and expanded positions in response to differential fluid pressure between the flowbore and the wellbore annulus. In one embodiment, the tool moves automatically in response to differential pressure. In a second embodiment, the tool must be selectively actuated before it is moveable. When the tool expands, the arms are preferably translated axially upwardly, while simultaneously being extended radially outwardly from the body. The expanded tool diameter is adjustable at the surface without changing components. The arms may include borehole engaging pads that comprise cutting structures or wear structures or both, depending upon the function of the tool.

Composite structures having a single continuous skin may be formed using automated fiber placement methods. These composite structures include frameless aircraft fuselage components offering an increased interior cabin width over conventional fuselage components. The composite structures may be constructed of multiple layers of fibers and other materials placed on a fiber placement tool that includes a mandrel body surrounded by a bladder or an integral bladder / caul sheet having expansion spaces created within the caul sheet section. Uncured composite structures may be created by placing fibers around the fiber placement tool in a plurality of discontinuous segments that are capable of moving or sliding in relation to each other so that the uncured composite structure is expandable from within. Fluid openings may be provided in the outer surface of the mandrel body for the application of vacuum and / or fluid pressure to secure the bladder to the mandrel body and to assist in the removal of the bladder from the mandrel body, respectively. Uncured composite structures may be sealed between the bladder and is clam shell molds. The uncured structures may be expanded against the inner surface of the molds by creating a vacuum between the bladder and molds.

A method of treating cardiovascular disease in a medical patient is provided. The method includes the steps of generating a sensor signal indicative of a fluid pressure within the left atrium of the patient's heart, and delivering an electrical stimulus to a location in the heart. The electrical stimulus is delivered based at least in part on the sensor signal. The method also includes the steps of generating a proccessor output indicative of a treatment to a signaling device. The processor output is based at least in part on the sensor signal. At least two treatment signals are provided to the medical patient. The treatment signals are distinguishable from one another by the patient, and are indicative of a therapeutic treatment. The treatment signals are based at least in part on the processor output.

A method and apparatus for alerting a user of topical negative pressure therapy apparatus to a full waste canister condition are described, the apparatus comprising a device having vacuum pump means and a waste canister connected to the device and the waste canister operably connected to a wound dressing by aspiration conduit means for aspirating fluid from the wound, the aspiration conduit means, the waste canister and the device providing a fluid flow path therethrough and the vacuum pump means providing fluid flow through the apparatus, the apparatus further comprising fluid flow restriction means in the fluid flow path of said vacuum pump and fluid pressure sensing means upstream and downstream of said fluid flow restriction means.

A drug delivery device includes a pressurized reservoir in communication with a flow path to an outlet. The flow path includes two normally-closed valves and a flow restriction. A pressure measurement arrangement measures a differential fluid pressure between two points along the flow path which span at least part of the flow restriction, one of the points being between the valves. A controller selectively opens the valves to deliver a defined quantity of the liquid medicament to the outlet.

The present invention relates to a variable-torque magnetorheologically actuated prosthetic knee which utilizes a plurality of interspersed and alternating rotors and stators to shear magnetorheological fluid 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-eliminating the need for a transmission-and also for a wide dynamic torque range. One embodiment of the invention allows the rotors and / or stators 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.

An improved pump, reservoir and reservoir piston are provided for controlled delivery of fluids. A motor is operably coupled to a drive member, such as a drive screw, which is adapted to advance a plunger slide in response to operation of the motor. The plunger slide is removably coupled to the piston. A method, system, and an article of manufacture for automatically detecting a force sensor failure in a medication infusion pump is provided. The electrical current to an infusion pump is measured. Based on the current measurements, the infusion pump detects when the plunger slide is seated in the reservoir, and detects a problem with the force sensor when the force sensor independently fails to register a value indicating that the plunger slide is seated in the reservoir.

An improved pump, reservoir and reservoir piston are provided for controlled delivery of fluids. A motor is operably coupled to a drive member, such as a drive screw, which is adapted to advance a plunger slide in response to operation of the motor. The plunger slide is removably coupled to the piston. A method, system, and an article of manufacture for automatically detecting a force sensor failure in a medication infusion pump is provided. The electrical current to an infusion pump is measured. Based on the current measurements, the infusion pump detects when the plunger slide is seated in the reservoir, and detects a problem with the force sensor when the force sensor independently fails to register a value indicating that the plunger slide is seated in the reservoir.

A method for discharging fluid from a syringe and for mitigating occlusion conditions includes actuating the plunger of a syringe into a barrel. The method monitors fluid pressure within the barrel of the syringe and determines that an occlusion exists when the fluid pressure exceeds a predetermined threshold. The method actuates the plunger out of the barrel by a predetermined amount in response to the detected occlusion and actuates the plunger of the syringe into the barrel until a measured fluid pressure within the barrel of the syringe exceeds another predetermined threshold.

A system for continuously circulating fluid to and through a tubular string either of coiled tubing or made up of a plurality of tubulars connected end-to-end while an upper tubular is added to or removed from a top tubular of the plurality of tubulars, all tubulars having a top-to-bottom fluid flow channel therethrough, the system having an upper chamber with a bottom opening, a top opening, and an upper sealing apparatus for sealingly encompassing a portion of the upper tubular, a lower chamber with a bottom opening, a top opening and a lower sealing apparatus for sealingly encompassing a portion of the top tubular, one of the upper chamber and the lower chamber sized for accommodating connection and disconnection therein of the upper tubular and the top tubular, and gate apparatus between and in fluid communication with the upper chamber and the lower chamber. Such a system may have apparatus for isolating a tubular therein from an axial load imposed by fluid pressure in a chamber; at least one of the lower chamber and the upper chamber with inner bushing apparatus with a portion thereof movably disposable within the chamber's sealing apparatus for facilitating movement of a tubular with respect to the chamber's sealing apparatus, and the system connectible to and rotatable by a rotating system for rotating the tubular string; and / or heave compensation interconnections for interconnecting the system to an offshore rig's heave compensation system. The system in certain aspects including fluid flow lines to each of the top and bottom chambers, a supply of fluid for circulating through the tubular string and through the upper and lower chambers, apparatus for continuously moving circulating fluid from the supply through the system into the tubular string.

A hydraulic fracture design model that simulates the complex physical process of fracture propagation in the earth driven by the injected fluid through a wellbore. An objective in the model is to adhere with the laws of physics governing the surface deformation of the created fracture subjected to the fluid pressure, the fluid flow in the gap formed by the opposing fracture surfaces, the propagation of the fracture front, the transport of the proppant in the fracture carried by the fluid, and the leakoff of the fracturing fluid into the permeable rock. The models used in accordance with methods of the invention are typically based on the assumptions and the mathematical equations for the conventional 2D or P3D models, and further take into account the network of jointed fracture segments. For each fracture segment, the mathematical equations governing the fracture deformation and fluid flow apply. For each time step, the model predicts the incremental growth of the branch tips and the pressure and flow rate distribution in the system by solving the governing equations and satisfying the boundary conditions at the fracture tips, wellbore and connected branch joints. An iterative technique is used to obtain the solution of this highly nonlinear and complex problem.

This invention provides a shunt for implantation between the anterior chamber of the eye and the epithelial-lined space through the frontal sinus bone of a patient for the treatment of glaucoma. The shunt includes a tube having a length sufficient to span the distance between the anterior chamber of the eye and the epithelial-lined space of the patient, the tube having an open anterior chamber end and a closed epithelial-lined space end, and a seal device associated with the tube between the anterior chamber and epithelial-lined space ends, for sealing a hole in the frontal sinus bone, and for anchoring the tube against movement from the frontal sinus bone. The shunt also includes a fluid pressure openable valve in the tube, located at or near the epithelial-lined space sinus end, allowing for controlled flow of aqueous humor through the tube when implanted. The invention also extends to a method of treating glaucoma in a patient by surgically implanting the shunt between the anterior chamber of the eye and the frontal sinus.

Embodiments of the invention generally relate to tools and methods for hanging and / or expanding liner strings. In one embodiment, a method of hanging a liner assembly from a previously installed tubular in a wellbore includes running the liner assembly and a setting tool into the wellbore using a run-in string. The setting tool includes an isolation valve and the liner assembly includes a liner hanger and a liner string. The method further includes sending an instruction signal from the surface to the isolation valve, wherein the isolation valve closes in response to the instruction signal and isolates a setting pressure in the setting tool from the liner string; and increasing fluid pressure in the setting tool, thereby setting the liner hanger.

A pumping system including a plurality of pumps each having a pump fluid outlet, a drive shaft, a prime mover, and fluid displacing members operatively coupled with the drive shaft. A common fluid conduit may be fluidly coupled with each pump fluid outlet. A control system of the pumping system includes position sensors operable to generate information relating to phase and / or speed of each pump, pressure sensors operable to generate information relating to fluid pressure spikes, and a controller in communication with the position and pressure sensors. The controller is operable to cause the prime movers to adjust the phasing of the pumps with respect to each other, based on the information relating to fluid pressure spikes, and synchronize the speed of the pumps.

A system and method for delivering a pledget of hemostasis promoting material to a blood vessel puncture to facilitate hemostasis, having an introducer sheath having an inner diameter and an outer diameter, a control tip coupled to the introducer sheath, and a self-expandable member disposed around a portion of the control tip to control blood flow at the blood vessel puncture.

A proportional valve is disclosed for controlling the outlet pressure of a fluid flowing therethrough. The valve comprises a valve body having an inlet port and an outlet port for the fluid. The valve also has an inner chamber, within which there is formed a valve seat that may be opened and closed variably by a shutter axially movable from and towards the valve seat. Movement of the shutter is controlled by a shape memory alloy (SMA) actuating member operating antagonistically to an elastic member, the temperature of the fluid being lower than the transition temperature of the shape memory alloy. The actuating member and the elastic member are connected to the body valve at opposite sides relative to the valve seat. A power control circuit is also provided for circulating an electric current through the actuating member so as to heat the same by Joule effect from a temperature lower than the transition temperature to one that is higher. At least one vent hole is formed in the valve body for putting a portion of the chamber upstream of the valve seat into fluid communication with the outside or a collection network. The actuating member is housed in that portion of chamber corresponding to the inlet port of the fluid, whereby a continuous flow of fluid around the actuating member is ensured for accelerating the cooling process. A closed-loop control circuit for the power control circuit controls the circulating current as a function of a pressure signal generated by fluid pressure sensing means and in such a way as to offset the retarding effect produced by the fluid during heating of the actuating member.

A pressure isolation mechanism for use in a medical procedure includes a lumen, an isolation port in fluid connection with the lumen, and a valve having a first state and a second state. The first state occurs when the lumen and the isolation port are connected. The second state occurs when the lumen and the isolation port are disconnected. The lumen remains open for flow of fluid therethrough in the first state and in the second state. The valve is preferably spring-biased in the first state and is switchable to the second state when fluid pressure in the lumen reaches a predetermined pressure level. Alternately, an actuator can control the state of the valve. A pressure transducer can be in fluid connection with the isolation port of the pressure isolation mechanism. A fluid delivery system includes a syringe and a pressure isolation mechanism as described above.

The fluid delivery system includes a pressurizing device for delivering injection fluid under pressure, a low pressure fluid delivery system, and a pressure isolation mechanism. The pressure isolation mechanism includes a first lumen associated with the pressurizing device, a second lumen associated with the low pressure fluid delivery system, and a pressure isolation port. The first valve is in a normally open position permitting fluid communication between the first lumen and the second lumen and movable to a closed position when fluid pressure in the first lumen reaches a predetermined pressure level. The first valve isolates the pressure isolation port from the first lumen in the closed position. A second valve is associated with the second lumen and regulates fluid flow through the second lumen. The second valve may be a disk valve defining one or more passageways in the form of slits through the body of the disk valve.

A shock absorbing bladder for use in the sole of an article of footwear is disclosed. The bladder includes a plurality of inflated chambers at different pressure levels. The bladder includes a first sealed chamber formed of a barrier material. The first chamber contains a fluid at a first fluid pressure. A second sealed chamber also forms part of the bladder. The second chamber is formed of a second barrier material and contains an inflation fluid at a second fluid pressure that is greater than said first fluid pressure. The second chamber is operatively coupled to the first chamber so that the inflation fluid from the second chamber moves into the first chamber to replenish fluid leaving the first chamber.

A downhole tool is disclosed that functions as an underreamer, or alternatively, as a stabilizer in an underreamed borehole. An embodiment of the tool includes one or more moveable arms disposed within a body having a flowbore therethrough in fluid communication with the wellbore annulus. The tool alternates between collapsed and expanded positions in response to differential fluid pressure between the flowbore and the wellbore annulus. In one embodiment, the tool moves automatically in response to differential pressure. In a second embodiment, the tool must be selectively actuated before it is moveable. When the tool expands, the arms are preferably translated axially upwardly, while simultaneously being extended radially outwardly from the body. The expanded tool diameter is adjustable at the surface without changing components. The arms may include borehole engaging pads that comprise cutting structures or wear structures or both, depending upon the function of the tool.

An expandable tubular sleeve having utility for lining a downhole tubular member includes a tubular body having a portion that is predisposed to initiate expansion thereof under the application of internal fluid pressure. The predisposed portion of the body may be a plastically-deformed portion formed, e.g., by application of mechanical force to a wall of the body. The predisposed portion of the body may be defined by a portion of the body having reduced wall thickness. The reduced wall thickness may be achieved, e.g., by reinforcing the wall thickness everywhere except the predisposed portion. The predisposed portion of the body may be formed by modifying the material properties of the body, e.g., by localized heat treatment. The sleeve and related apparatuses and methods are useful for securing and protecting a cable having one or more insulated conductive wires for transmission of signals between locations downhole and at the surface.

A MEMS chip sensor (10, 20, 30, 40, 50, 60, 70) based upon detection of an induced inductance in the sensor is described. The sensor is used in an environment for detection of fluid pressures. The method and system is particularly used in animals, including humans, to sense pressure changes, particularly pressure in the eyeball.

A pumping system including a plurality of pumps each having a pump fluid outlet, a drive shaft, a prime mover, and fluid displacing members operatively coupled with the drive shaft. A common fluid conduit may be fluidly coupled with each pump fluid outlet. A control system of the pumping system includes position sensors operable to generate information relating to phase and / or speed of each pump, pressure sensors operable to generate information relating to fluid pressure spikes, and a controller in communication with the position and pressure sensors. The controller is operable to cause the prime movers to adjust the phasing of the pumps with respect to each other, based on the information relating to fluid pressure spikes, and synchronize the speed of the pumps.

A massage device for massaging a body part of a person in an unsupervised and unattended setting. The massage device includes a garment, shaped to provide a snug fit and having a plurality of bladders arranged along the garment to massage the body part. An inflation assembly supplies fluid pressure to each of the bladders to inflate the respective bladders. The bladders may have approximately the same inflated volume thereby equalizing the inflation volume of the respective bladders whereby substantially even inflation timing, with substantially even applied pressure, and, thus, overall smooth massage dynamics may be provided without overly complicated inflation fluid control (e.g., an inflation assembly which supplies a substantially constant inflation capacity to each of the bladders). The garment may include a pocket having an opening communicating with the respective bladders and tubing from the inflation assembly extends into this pocket. The inflation assembly may provide throttled deflation flow, tapered inflation / deflation patterns, and / or a zone selector which allows a user to select a certain zone of the garment.

The normal control of an electrically-activated hydraulic valve armature is overridden to automatically and periodically open the armature for flushing out debris that has accumulated between the armature and a seat that the armature is designed to engage. The valve develops fluid pressure for maintaining engagement of a motor vehicle transmission clutch, and when excessive slippage of the clutch is detected, the armature is forced into engagement with the seat until the slippage is reduced or a predetermined period of time has elapsed, after which the armature is temporarily positioned away from the seat to provide full flow of hydraulic fluid across the seat to flush out debris that prevents the armature from engaging the seat. During Neutral operation of the transmission, the armature is continuously positioned away from the seat, and during low torque conditions the armature is temporarily positioned away from the seat.

A service tool string (34) is releasably attached to a bottom hole assembly (18) and forms a production string as well as a work string. The tool (35) has a mandrel (102) and a slide valve assembly (68) mounted on the mandrel for relative sliding movement. Crossover ports (114, 124) are provided in the mandrel (102) and the slide valve assembly (68). Slide valve assembly (68) moves by gravity and spring action when not contacted by the bottom hole assembly (18) to a position in which ports (114, 124) are blocked as shown in FIG. 7B. Upon contact of slidable valve assembly (68) with the bottom hole assembly (18), slide valve assembly is moved upwardly for alignment of ports (114, 124) as shown in FIGS. 5B and 6B. An equalizing valve (29) as shown in FIGS. 10-12 is effective to equalize the fluid pressure within the bottom hole assembly (18) with the fluid pressure outside the perforated casing section (23) so that in a reverse position as shown in FIG. 7B, the service tool (35) can be lifted to a position above the upper packer assembly (26) and above the bottom hole assembly (18). A diverter ball (132) seated on a ball catcher (134) is effective to divert the fracturing fluid outwardly through crossover ports (114, 124) as shown in FIG. 6B for downward flow through the annulus (27) into the formation adjacent the perforated casing section (23).