183results about How to "Avoid pressure fluctuations" patented technology

Parallel uses of microfluidic methods and devices for focusing and / or forming discontinuous sections of similar or dissimilar size in a fluid are described. In some aspects, the present invention relates generally to flow-focusing-type technology, and also to microfluidics, and more particularly parallel use of microfluidic systems arranged to control a dispersed phase within a dispersant, and the size, and size distribution, of a dispersed phase in a multi-phase fluid system, and systems for delivery of fluid components to multiple such devices.

The invention relates to a fuel pressure damping system for use in a hydraulic system. The invention introduces specifically sized restrictors in the fuel passage to control the maximum operating system pulse magnitude as well as damping the overall pulsations of the system.

A boil off gas (“BOG”) condenser for use in LNG handling facilities which provides compensation for transient pressure changes in BOG flow due to variations in operations.

The invention relates to an active hydraulic damper specially for railway vehicles, comprising a hydraulic cylinder, an electric motor, a hydraulic accumulator, at least a pump and at least a control valve. According to the invention, all components of the active hydraulic damper are arranged at the hydraulic cylinder.

The invention discloses an energy recovery system for a load sensing hydraulic system, and belongs to the technical field of engineering machinery. The energy recovery system comprises a signal detecting unit, a control unit, an energy recovery unit and an energy storage unit. The signal detecting unit is used for detecting the pressure on the oil inlet side of a hydraulic system execute mechanism when load decreases and converting the pressure into digital signals to transmit to the control unit. The control unit is used for receiving detecting signals, processing the detecting signals by corresponding control algorithm to generate control signals and transmitting to the energy recovery unit. The energy recovery unit is used for converting hydraulic energy into power and adjusting working states according to a control signal in real time. The energy storage unit is used for storing or releasing power according to the system operating states. The energy recovery system aims to a feature of the loading sensing technology, and allows adjustment of variable hydraulic motor output volume in the energy recovery unit to be automatically coordinated with actions of a multi-way valve in the load sensing system, and application of the power-type energy recovery technology in the load sensing hydraulic system is realized.

The invention is a fan revolution control method for controlling a pump-motor system, by controlling the fan revolution speed of a cooling fan adapted to be rotated by a fan motor to cool cooling target fluids. The pump-motor system drives the fan motor by a hydraulic fluid fed from a fan pump driven by an engine. The pump-motor system is controlled so the fan revolution speed starts from the minimum fan revolution speed when the engine is started up; the minimum fan revolution speed is maintained for at least several seconds; after the elapse of several seconds, the fan revolution speed is gradually increased from the minimum fan revolution speed. The fan revolution speed reaches a target fan revolution speed over a period of at least several seconds. The method prevents generation of peak pressure or pressure hunting.

The system includes: a variable displacement hydraulic pump supplying pressure oil to a hydraulic actuator; a pressure detector detecting a pump discharge pressure from the hydraulic pump; a control valve controlling a supply of the pressure oil to the hydraulic actuator; a controller controlling a pump displacement of the hydraulic pump; a hydraulic motor rotating an upper structure of the construction machine; a swing relief valve defining a relief pressure of the hydraulic motor; and a control lever switching a control valve for the hydraulic motor. The controller includes: an adjuster that, when a pump discharge pressure detected by the pressure detector exceeds a first set value, conducts an adjustment to reduce the pump displacement; and a canceller that cancels the adjustment when the pump discharge pressure falls below a second set value. The second set value is equal to or larger than the first set value.

A transmission apparatus (10) having at least one form-lock shifting element (12) that can be actuated by a hydraulic system (11) which, in the region of a piston chamber, can be subjected to hydraulic pressure (p—12) via a hydraulic fluid-conducting feed line (20) and which can be actuated from a disengaged to an engaged operating state. The hydraulic fluid-conducting feed line (20) of the shifting element (12) is effectively connected to a damping device (22) by which pressure fluctuations, of the hydraulic pressure (p—12) in the feed line (20), can be at least partially compensated.

A gas turbine combustor of the present invention includes a cylindrical combustor liner, a cylindrical combustion chamber inside the combustor liner, and a burner that includes a plurality of fuel nozzles for injecting the gas fuel into the combustion chamber and an air hole plate with a plurality of air holes for guiding the compressed air into the combustion chamber. The air hole plate joins the combustor liner and is disposed between the fuel nozzles and the combustion chamber. The junction between the air hole plate and the combustor liner is provided with an inclined component which covers the junction and has a connecting surface connecting the air hole plate and the combustor liner.

A fluid supply apparatus which supplies a fluid to a medical apparatus includes: a pump mechanism including a first pump capable of carrying out a intake operation of a fluid and a feeding operation of the fluid, and a second pump capable of alternately carrying out a intake operation of the fluid and a feeding operation of the fluid; a flow passage which includes an elastic member and which communicates with the pumps and supplies the fluid to the medical apparatus; a pressure fluctuation detecting unit capable of detecting fluctuation in internal pressure in the flow passage; and a flow passage deforming unit which deforms the flow passage according to the fluctuation in the internal pressure.

The invention is a fan revolution control method for controlling a pump-motor system, by controlling the fan revolution speed of a cooling fan adapted to be rotated by a fan motor to cool cooling target fluids. The pump-motor system drives the fan motor by a hydraulic fluid fed from a fan pump driven by an engine. The pump-motor system is controlled so the fan revolution speed starts from the minimum fan revolution speed when the engine is started up; the minimum fan revolution speed is maintained for at least several seconds; after the elapse of several seconds, the fan revolution speed is gradually increased from the minimum fan revolution speed. The fan revolution speed reaches a target fan revolution speed over a period of at least several seconds. The method prevents generation of peak pressure or pressure hunting.

The invention relates to an automatic control system alternatively filled with simulated polymer solution. The automatic control system is characterized by comprising a polymer alternative filling experimental device and an automatic switching control device; a constant-flux pump output end in the polymer alternative filling experimental device is linked with input ends of three middle containers in parallel, and output ends of the three middle containers are connected with an input end of a rock core holding unit; the bottom part of the output end of the core holding unit is provided with a fluid collecting container, and the core holding unit is further connected with a pressure confining pump. High-pressure pneumatic valves in the automatic switching control device are respectively arranged at the input end and the output end of every middle container, and every high-pressure pneumatic valve is connected with an electromagnetic valve group; the working air source of the electromagnetic valve group is provided by the air compressor. A pressure sensor is respectively arranged between every high-pressure pneumatic valve and the output end of the middle container, and the input end of the core holding unit is also provided with a pressure sensor. The signal detected by every pressure sensor is transmitted to a computer through a control box to control. The automatic control system alternatively filled with simulated polymer solution can be widely applied to related experiments for improving oil recovery of chemical flooding in an oilfield.

In a pressure-maintaining device for a fuel supply system of an internal combustion engine (1) of a motor vehicle, a pressure reservoir (5) is arranged in a supply line (7) leading to the internal combustion engine (1). The pressure reservior (5) has a pressure chamber (13), which is bounded by a movable wall (14) that is pretensioned by a compression spring (15). The position of the movable wall (14) is registered by a displacement transducer (18) and forwarded to a regulating device (12). The regulating device (12) regulates the rotational speed of a fuel pump (3) as a function of the position of the movable wall (14).

An apparatus for cutting and aspirating tissue from the human body or animal body, particularly for application in vitrectomies, for retinal detachment, etc., having an outer tube (1) and an inner tube (5) which can slide back and forth concentrically in the outer tube (1) with minimal play, wherein the outer tube (1) is closed on the free end (2) thereof, and has a lateral opening (3) near the free end (2), with at least one inner cutting edge (4), wherein the inner tube (5) is open on the free end and has an outer cutting edge (6) at that position, and wherein the cutting edges (4, 6) work together in a cutting manner when the inner tube (5) is displaced, characterized in that the inner tube (5) has at least one lateral opening (7) with at least one further outer cutting edge (8) near the free end.

The invention discloses an immersion liquid supply and recovery control device for a mask aligner. The immersion liquid supply and recovery control device is arranged between a projection lens group and a substrate to be exposed and consists of a liquid charging cover, a liquid charging disc, a flow control loop and a retainer ring. The external liquid charging and the internal liquid recovery are adopted. Liquid enters a slit flow field from the periphery with the fixed quantity and in the mode of high speed injection; and the balance and stability of the whole flow field is realized through coordination and control of the negative pressure acting on an internal recovery cavity. The mode of high speed liquid injection from outside to inside can not only effectively counteract the internal power of outward liquid leakage and reduce the infiltration of boundary air bubbles caused by a gas sealing device, but also quicken the updating rate of the flow field and consequently facilitate the timely removal of pollutants produced in the process of exposure.

The no-fluctuation hot blast stove changing method belongs to the field of blast furnace iron smelting technology in metallurgic industry, and aims at providing stove changing method without fluctuation in cold air blast pressure. The method is that during changing hot blast stove from combustion state to air blast state, cold air is pressurized to the hot blast stove for feed the hot blast from the hot blast stove to the blast furnace before making the hot blast stove enter the air blast state. The cold air from the independent compressed air packet is purified and dewatered before being led into the hot blast stove through a equalizing valve. The method can avoid pressure fluctuation during stove changing, ensure continuous stable air blast, short stove changing time, raised blast temperature and realize the automatic control of stove changing pressurizing.

The invention relates to a valve for a piston pump, wherein the valve (22) comprises a valve closure body (10) and a valve seat (26) disposed longitudinally facing to the valve closure body (10); the valve closure body (10) comprises a cylindrical guide section (12) and a hemispheric sealing section (14) longitudinally facing to the cylindrical guide section (10) and facing to the valve seat (26); the sealing section is used for selectively closing and opening a hole (30) enclosed by the valve seat (26); according to the invention, the sealing section (14) comprises at least one channel opening (16) which is located out of the hole (30) enclosed by the valve seat (26) under the state that the valve (22) is closed, and extended into a channel (18) in the valve closure body (10) substantially extending along a flow direction.

The invention provides a respiration air feed system (100). The respiration air feed system is provided with a main pipe (1), wherein the input end (11) of the main pipe (1) communicates with the outside air, and the output end (12) of the main pipe (1) communicates with an air using unit. The respiration air feed system comprises air inlet devices (2a and 2b), preprocessing apparatuses (3a and 3b), an air monitoring apparatus (4), a secondary air storage tank (5) and a temperature adjusting apparatus (6), wherein the air inlet devices (2a and 2b) are used for sucking in air from the outside world and compressing the air, the preprocessing apparatus (3a) comprises a drying device (31a) used for drying air, a primary air storage tank (32a) used for temporarily storing the air and a filtering device (33a) used for filtering out the unwanted ingredients in the air, the preprocessing apparatus (3b) comprises a drying device (31b) used for drying air, a primary air storage tank (32b) used for temporarily storing the air and a filtering device (33b) used for filtering out the unwanted ingredients in the air, the air monitoring apparatus (4) comprises a detecting device (41) and an analysis control device (42), the detecting device (41) is used for detecting the content or contents of one or more ingredients in the air, the analysis control device (42) is used for analyzing the detection results and giving out control signals according to the analysis result, the secondary air storage tank (5) is used for buffering the pressure of air, and the temperature adjusting apparatus (6) comprises a cooling device (61) used for cooling air and a heating device (62) used for heating air.

A high pressure pump has a housing with a crank shaft which drives a plurality of pistons in each case via a connecting rod, with each piston being guided in a cylinder which is secured to a cylinder head and which sucks fluid from an inlet and delivers it under pressure to an outlet.

The invention discloses a pressure adjusting device for adjusting pressure of a hydraulic system, which comprises a valve body, a first valve spool and a first elastic part. When fluid pressure acts at an inlet end of the first valve spool, part of fluid enters a first elastic chamber via a first flow channel; and when a pressure difference exists between the inlet end and an outlet end of the first valve spool, the pressure difference enables the first valve spool to axially slide along a first main chamber. The invention further discloses the hydraulic system. The pressure adjusting device and the hydraulic system are simple in structure, convenient in mounting, demounting and maintenance and capable of effectively reducing interference pressure caused by external interference, so that system pressure fluctuation is prevented.

An electrohydraulic shock-wave therapy apparatus comprising a variable voltage source and a controller that controls said voltage source for accurate adjustment of the shock wave pressure. The invention, in various embodiments, also includes various methods, optionally closed loop as well as open loop based, for determining the shock pressure while compensating for burnout and or erosion that normally suppress the pressure after some thousands of sparks. This way the effective lifetime of the electrodes is dramatically extended. The control is further used for significantly increasing the effective therapeutic area of the apparatus by adjusting the shock pressure value close to the maximal safe value.

A polymer treating method has the steps of: reacting a polymer compound with a reaction agent in a reaction vessel to generate a polymer treatment product; discharging the polymer treatment product containing the reaction agent from the reaction vessel; depressurizing the polymer treatment product; introducing the polymer treatment product into a degassing extruder; separating the reaction agent from the polymer treatment product through a vent box that is connected to upstream of the degassing extruder and that has a volume of equal to or more than that of the reaction vessel; and extruding the polymer treatment product from the degassing extruder.

The invention relates to a soft sealing safety valve. The soft sealing safety valve comprises a barrel-shaped valve body, a left blocking cap and a right blocking cap, wherein the left blocking cap and the right blocking cap are correspondingly fixed to the left end and the right end of the valve body; the valve body is provided with a first oil port and a second oil port; a tapered valve element is arranged in the middle of an inner cavity of the valve body, a spring is arranged between the tapered valve element and the left blocking cap, and a valve base is fixed between the tapered valve element and the right blocking cap; a stepped hole is formed in the valve base, a soft sealing ring is fixed into the stepped hole through a screw plug, and the screw plug is provided with a through hole along the central axis of the screw plug; the tip of the tapered valve element stretches into an inner hole of the soft sealing ring; the first oil port communicates with the right end of the stepped hole of the valve base, and the second oil port communicates with the portion, between the tapered valve element and the left blocking cap, of the inner cavity of the valve body. The soft sealing safety valve has the advantages of being simple in structure, safe, reliable, good in sealing effect and adjustable in switch-on pressure.

The invention relates to the technical field of working face hydraulic systems and provides a pressure stabilizing and liquid supplying method capable of adapting to hydraulic support movement. The support system hydraulic process is divided into three stages, namely, a system liquid leakage stage, an energy accumulator liquid supplying stage and a pump liquid supplying stage; support movement andpressure changing in the three stages are analyzed correspondingly to obtain the pressure stabilizing and liquid supplying flow quantity; and executable liquid supplying strategies are further formedaccording to the pressure stabilizing and liquid supplying flow quantity, and output of the liquid supplying flow quantity is specifically achieved through an executing mechanism. According to the pressure stabilizing and liquid supplying method capable of adapting to hydraulic support movement, by judging the conditions such as support movement and pressure changing, in order to increase the support movement speed and stabilize the hydraulic system pressure, liquid is efficiently and stably supplied in the hydraulic support movement process; in the liquid supplying optimizing process, the movement speed of a support is maintained and slightly increased, and when movement is completed, the set unloading pressure is right achieved, and the pressure fluctuation phenomenon is effectively avoided; and the propelling speed of the coal mine working face can be increased, the equipment loss of a hydraulic system is reduced, and the application prospects are considerable.

An oil strainer includes: a lower member having an oil suction hole opening in oil stored in an oil pan; an upper member having an oil discharge hole leading to an oil pump; and a strainer element. The lower member and the upper member are joined to each other with the strainer element held between joint surfaces of the upper and lower members. Thus, it is possible to form the oil strainer into a flat shape so as to be compactly arranged in a narrow space, and also maximize an area of the strainer element to prevent clogging. Further, the lower member and the upper member, which are die-molded articles, are highly flexible in their shapes, whereby the oil suction hole and the oil discharge hole can be arranged in the most suitable positions, and the cross-sectional area of oil flow can be sufficiently secured.

A shaft sealing apparatus capable of preventing gases vaporized from a gas seal or purge fluid from leaking outside before a pressure switch operates due to a pressure rise resulting from a fluid leakage from a mechanical seal. The apparatus comprises a seal casing and a rotary shaft passing through the former and having a mechanical seal A and a dry gas seal B mounted thereon in line with each other to provide purge fluid areas C therebetween. With this arrangement, a purge fluid is supplied to one of the purge fluid areas through a supply line having an orifice OA and the supplied purge fluid and a leaked part of a target fluid to be sealed are released outside from the other purge fluid area through a relief line having an orifice OB. The relief line is provided with a bypass line with an electromagnetic valve and a pressure switch and bypassing the orifice OB. In this case, the purge fluid supply pressure P1, the preset pressure P2 between the orifices OA and OB, the pressure P3 in the area from the orifice OB to outside and the pressure switch operating pressure P<SMALLCAPS>s < / SMALLCAPS>satisfy the relationships of P1>P<SMALLCAPS>s< / SMALLCAPS>>P2>P3.

The present invention relates to a dispenser (1) for discharging liquid state or slurry-shaped material. The dispenser (1) includes a pump head (2) and a pump chamber (8) which comprises a pump chamber wall (20) arranged in the pump chamber, an inlet valve (26) and an outlet valve (11). The dispenser (1) also includes a storing container (3) which is accommodated with a storing bag (4) that can reduce the dimension for discharging. The pump chamber wall (20) of the pump head (2) is formed with a flexible mode to obtain a design which has an advantage at vibrating or pressure abrupt increasing aspect.

The invention provides a hydraulic system for heating and cooling high-pressure oil liquid. The hydraulic system comprises a first hydraulic cylinder and a second hydraulic cylinder, and the first hydraulic cylinder and the second hydraulic cylinder are connected to a three-position four-way servo valve; the three-position four-way servo valve is connected to an oil tank through a hydraulic pump and an oil suction filter; the first hydraulic cylinder and the second hydraulic cylinder are connected to a hydraulic bridge through a first isolation cylinder and a second isolation cylinder respectively; one circuit of the hydraulic bridge is connected to a product to be tested through an energy accumulator and a heating and cooling device; and the other hydraulic circuit is connected to the product to be tested. The hydraulic system for heating and cooling the high-pressure oil liquid has the advantages that isolation of normal-temperature hydraulic oil from high-low-temperature oil can be realized, pressurizing and reversing of the system are carried out at the normal-temperature side, and therefore use of the hydraulic pump, the servo valve and other high-low-temperature hydraulic parts can be avoided, the high-low-temperature end is placed in the heating and cooling device, the heating and cooling power is small, safety and reliability can be achieved, and the cost is low.