158 results about "Reciprocating flow" patented technology

A high-pressure wear resistant cylinder that utilizes a high-pressure field for strength is an economical method of, or device for, handling very high pressures and the pumping of abrasive and corrosive fluids. The economic considerations are so favorable, that the invention may be considered a replacement part. The invention is suitable for a variety of applications, particularly a reciprocating flow work exchanger in the well stimulation or hydraulic fracturing industry. Using a high pressure field to strengthen the external surface (outside) of a pipe that is precision honed and plated or sleeved internally (inside), it is now possible to construct various high pressure machines in a relatively inexpensive manner. This invention makes it possible to use pipe with internal operating pressures greater than their nominal operating pressure ratings permit. This invention will be used in various high pressure piping and machinery applications.

The invention relates to an ablation catheter which controls the temperature and reduces the coagulation of biological fluids on an electrode of a catheter, prevents the impedance rise of tissue in contact with the electrode, and maximizes the potential energy transfer to the tissue, thereby allowing an increase in the lesion size produced by the ablation. The electrode includes passages positioned to allow blood and other biological fluids to flow into and out of an inner cavity of the electrode. This fluid flow produced the desired cooling effect and is accomplished, for example, by a reciprocating plunger or piston, or by a balloon that is alternately inflated and deflated.

The invention discloses a special clamp for abrasive flow polishing of a narrow flow passage closed impeller flow passage. The special clamp comprises an upper mold, a lower mold, a floating lock and a gasket support plate, wherein the upper mold and the lower mold form a cylindrical cavity; the inner diameter of the cylindrical cavity is greater than the diameter of the impellers; the gasket support plate is a round disc having the diameter as the same as the diameter of the impellers; the floating lock consists of an upper round disc and a lower round disc and a double-head stud and a bolt which are used for connecting the two round discs; the mounted floating lock can move between the gasket support plate and the lower mold; the impellers are arranged on the gasket support plate, and are fastened by the upper mold and the lower mold; and the upper mold and the lower mold are positioned through seam allowance, and are fixed by the bolts. The clamp for abrasive flow machining of the narrow plow passage closed impellers can be used for fixing the impellers and can guide abrasive materials to flow through the surface of the impeller flow passage, and keep a given pressure so as to grind and polish the internal part of the impeller flow passage, form a circular loop and realize reciprocating flow of the abrasive materials.

The invention relates to an ablation catheter which controls the temperature and reduces the coagulation of biological fluids on an electrode of a catheter, prevents the impedance rise of tissue in contact with the electrode, and maximizes the potential energy transfer to the tissue, thereby allowing an increase in the lesion size produced by the ablation. The electrode includes passages positioned to allow blood and other biological fluids to flow into and out of an inner cavity of the electrode. This fluid flow produced the desired cooling effect and is accomplished, for example, by a reciprocating plunger or piston, or by a balloon that is alternately inflated and deflated.

An electro-rheologic vibration absorber with damping continuously adjustable function in air charging type is prepared as embedding columnar electro-rheologic spring and compressing valve as well as drawing valve in piston of said absorber, setting oil channel on piston to let hydraulic oil flow in reciprocation way, using float piston to divide cylinder to be two parts of up oil chamber and down air chamber, setting piston rod to be hollow structure being used to pass wire to be connected with electro-rheologic spring and charging electro-rheologic fluid with apparent viscosity being controlled by externally exerted magnetic field in said spring.

The invention relates to low-concentration gas and ventilation air methane thermal oxidation generating system and method of a coal mine. The system mainly comprises a multi-gas oxidation device, a water treatment device, a screw rod type expander, a generator, a condenser and the like. In the method, low-concentration gas and ventilation air methane of the coal mine are adopted to carry out periodic reciprocating flowing type superheated oxidation reaction in a porous ceramic oxidation bed, the reaction heat is extracted with work medium water through an internal heat exchanger, generated superheated vapor enters the screw rod type expander to do work, and the heat energy is converted to the mechanical energy to drive the generator to generate the power. The system and the method have the advantages of simpleness, reasonable single machine capacity matching, convenience in operation and good use effect.

The invention relates to a device for simulating reciprocating flow riverway in-situ bottom mud resuspension and a simulation technology thereof. According to the device for simulating the reciprocating flow riverway in-situ bottom mud resuspension, an upstream flow water level control device comprises a first water inlet pipe, an upstream water level control water tank, an upstream backflow simulation water tank, a first siphon backflow pipe and a first water outlet pipe; a water tank device comprises a water tank body, a bottom mud tank, a flow velocity gauge, a turbidity meter and at least two sampling ports; a downstream tide simulation control device comprises a tide water level control tank, a second siphon backflow pipe, a tide backflow simulation water tank, a backflow water tank, an overflow pipe, a variable frequency water pump and a second water outlet pipe; an experiment platform automatic control device comprises a first resistance-type liquid level meter, a second resistance-type liquid level meter, a first pulling line, a second pulling line, a first direct current brushless motor, a second direct current brushless motor, a first movable pulling plate and a second movable pulling plate. The simulation technology comprises the steps of bottom mud preparing, overlying water preparing, flow velocity gauge and turbidity meter installing, unidirectional flow simulating, tide reciprocating flow simulating and water sample measuring. The simulation accuracy is high, and the device for simulating the reciprocating flow riverway in-situ bottom mud resuspension and the simulation technology thereof can be popularized.

The invention relates to an extruding machine, in particular to the extruding machine with double flow passages machine cylinder heating and cooling devices. Two strips of double flow passages that are not communicated with each other are processed at the interior of the machine cylinder and respectively relate to a heating flow passage and a cooling flow passage; two ends of each flow passage are respectively an oil inlet and an oil outlet. The invention changes the traditional thermal balance principle from another view; the heating and the cooling are finished by heat transfer oil; the heating oil and the cooling oil are carriers for thermal balance; the machine barrels of the double flow passages are main bodies for the heating oil and the cooling oil to carry out heat exchange. The two flow passages are not communicated with each other, only the reciprocating flow is carried out along the axial direction in parallel; therefore, the machine can run normally when the machine cylinder is ensured to be controlled under the required temperature.

The invention discloses a lithium ion liquid flow battery system which comprises a battery module group, wherein the battery module group comprises a battery module or more than one serially connected battery module; each battery module comprises a battery sub module or more than one parallelly connected battery sub module; each battery sub module comprises at least two connected battery units. A liquid supply system of each battery module forming the battery module group is independent and adopts a positive electrode liquid storage device and a negative electrode liquid storage device respectively; liquid conveying pipelines are independent; each battery sub module is an independent whole capable of feeding and discharging liquid independently; all the battery modules in the battery module group share a dynamic circulating device; positive and negative electrode suspensions are driven by the dynamic circulating device to do periodic reciprocating flowing in a closed space consisting of the liquid storage devices, the liquid conveying pipelines and the battery modules.

The invention provides a thermoelectric generation system through countercurrent oxidation of mine ventilation air, which belongs to the technical field of performing efficient temperature-difference thermoelectric conversion by utilizing countercurrent oxidation of methane in mine ventilation air to release heat. Gas containing methane extremely low in concentration can be subjected to self-sustained periodic reciprocating-flowing oxidation in a countercurrent oxidation bed of the system so as to form a middle high-temperature region of which the temperature is far higher than a theoretic adiabatic combustion temperature; the hot end of a thermoelectric generation unit is in contact with an inner insulating board in the region; and the cold end of the thermoelectric generation unit is in contact with an outer insulating board connected with a heat exchanger. As a great temperature gradient is produced between the hot end and the cold end of the thermoelectric generation unit, efficient thermoelectric-conversion power generation can be performed with no complex steam cycle or power generation system, and the temperature-difference thermoelectric conversion efficiency of the thermoelectric generation system is obviously higher than conventional thermoelectric generators. The thermoelectric generation system is characterized by simple equipment, compact structure, low cost and high efficiency, and efficiently provides an effective method and equipment choice for controlling and utilizing mine ventilation air.

The invention provides a pumpless circulation method for a small skid-mounted evaporation gas reliquefaction and recovery device for liquefied natural gas. The pumpless circulation method includes the steps: taking a regenerative cryo refrigerator (3) as a cold source to perform condensation and liquidation on boil off gas (9) generated from the liquefied natural gas (2) in a cryogenic storage tank (1); enabling the liquefied natural gas (2) formed in condensation to flow back to the cryogenic storage tank (1) under the action of gravity through a pipeline. Circular reciprocating flow of gas liquid inside the system is sustained under the action of differential pressure and gravity, and cryopumps are not required to provide circular power, so that the integral structure and technological process of the device are simplified, energy consumption is lowered, and economical efficiency in operation of the device in improved; real-time monitoring and stepless regulation can be performed on cryogenic temperature and output cold of the cryo refrigerator according to changes of actual pressure and heat loads inside the cryogenic storage tank, zero consumption of a storage tank system can be realized, and stability, reliability and control precision in operation of the device are improved.

Disclosed is a refrigeration cycle device (100) comprising a low-pressure stage compressor (113), a high-pressure stage compressor (101), a radiator (103), a gas-liquid separator (107), an expansion valve (109), an expander (105), and an evaporator (111). The low-pressure stage compressor (113) and the expander (105) are coupled by a shaft (116), and the low-pressure stage compressor (113) is driven by power recovered from the refrigerant by the expander (105). The low-pressure stage compressor (113) and the high-pressure stage compressor (101) are connected in series by an intermediate-pressure flow channel (114). The gas-liquid separator (107) and the intermediate-pressure flow channel (114) are connected by a reciprocating flow channel (115). The reciprocating flow channel (115) is configured to allow the bidirectional flow of refrigerant therethrough. The refrigerant flow rate through the reciprocating flow channel (115) is regulated by controlling the degree of opening of the expansion valve (109).

The invention relates to a method for evenly coating fluorescent powder on a spiral fluorescent lamp tube. A functional device with rotation and revolution is adopted to make the fluorescent powder slurry layer in the spiral curved glass tube evenly coated and slowly solidified, and the normal temperature air is used as a moisture absorbing method. Infrared radiation, drying in an oven and reciprocating flow of circulating air are used to dry and reinforce the coating process to ensure that the phosphor layer is not too thick and has a uniform thickness, which is conducive to ensuring the quality of spiral fluorescent tubes and can be improved by at least 3 More than 100% of the luminous efficiency, save more than 10% of the phosphor, and the device can be equipped with a considerable number of spiral curved glass tube mounting supports in the form of multiple heads and multi-stations, slow rotation, sequential operation, and cyclic operation, greatly improving It improves work efficiency and product quality, avoids the special hot air dehumidification process of about 90°C in the prior art, reduces the production cost of the product, and has many advantages such as reliable operation, convenient use and obvious energy saving effect. Remarkable economy and strong practicality.

The invention belongs to the technical field of aftertreatment of marine diesel engine particulate matter emission control, and particularly relates to a reciprocated flowing type marine diesel enginecontinuous catalyzing regenerating diesel oil particle filter. According to the filter, an adverse current oxidation device is used for achieving the principle that ultra-thin organic substance is subject to reciprocated flowing within a self-maintaining period to be subject to oxidation treatment, and the reciprocated flowing type marine diesel engine novel continuous catalyzing regenerating DPFsuitable for a marine diesel engine burning heavy oil. The novel DPF technology is applied into the marine diesel engines burning heavy oil, a marine diesel engine particulate matter control device has the advantages of small flowing resistance, the good particulate matter removing effect, the compact structure, easiness in regeneration, high catalyst sulfur poisoning resistance and the like, integrated matching of the marine diesel engine particulate matter control device and a diesel engine host, an SCR denitration device and a wet-type washing desulfurizer is easily achieved, and the integrated treatment effect of desulfuration, denitration and particulate matter removal of waste gas of the marine diesel engine is achieved.

The invention discloses a pier local scouring protection device with a rotary normal curved surface. The protection device is sleeved on a pier and is approximately in a bell shape, the thickness of the protection device is 0.5-1 m, and the inner surface of the protection device meets an equation of a standard rotary normal curved surface. The protection device is combined with the reciprocating flow characteristic, front impact water flow can be dispersed, the protection device is lifted away from the periphery of the pier in the tangential direction of a convex surface, and water flow impactis reduced; on the other hand, downward scouring water flow can be guided, downward scouring continues to be carried out, the direct scouring effect of the downward scouring water flow on a bed surface is weakened at the position farther away from the pier along the concave surface, and part of front impact water flow can be counteracted; and meanwhile, horseshoe vortexes around the pier are reduced, scouring of the horseshoe vortexes to a pier riverbed is weakened, and meanwhile the stress influence on the pier is small.

The embodiment of the invention provides a pump station approach channel and forebay sand-containing moving bed surface flow velocity distribution determination method and device, and the method comprises: obtaining a reciprocating flow outer boundary layer flow velocity, a flow period, a sediment particle size, a ratio of sediment to water density through measurement, and obtaining a sand-containing moving bed surface friction factor, a Sierz number and a sediment sedimentation velocity; and further obtaining a phase difference and a phase lead of the flow velocity section of the sand-containing moving bed surface. Related phase difference and phase lead are determined, the influence of phase difference on flow velocity distribution is reflected, phase residue and phase drift of relativeflow velocity of the reference surface position of flow velocity distribution in the reciprocating flow process are reflected, asymmetry of flow velocity distribution of the moving bed surface in theflow acceleration and deceleration stages is reflected, the flow velocity prediction capacity of a high-sand-content area near the moving bed surface is improved, and the upper bound of the flow velocity is accurately captured.

The invention belongs to the technical field of transmissions, and particularly relates to a gearbox based on hydraulic transmission. The gearbox comprises two torque hydraulic conversion mechanisms, a first liquid duct, a gearbox body, a driving gear, a transmission gear, a base and a second liquid duct, the torque hydraulic conversion mechanisms convert between rotation of a transmission shaft and reciprocating flow of liquid, and when the torque hydraulic conversion mechanisms are in matched use, torque transmission effect of the transmission shaft in complex spatial distribution can be realized; the gearbox is designed to have three gears, and three transmission gears and one driving gear are meshed; the driving gear is mounted on a combination base which can move transversely and longitudinally, and the driving gear moves along a plane of the base to selectively drive one of the three transmission gears to realize gear shifting. The liquid duct is connected with the transmission shaft to separate out a power input shaft in the gearbox, mounting flexibility of the gearbox is improved, and the gearbox has a good application prospect.

The invention discloses a three-valve hot-air engine, and the three-valve hot-air engine includes an air cylinder piston mechanism and a combustion chamber. An air cylinder of the air cylinder piston mechanism is provided with an air inlet. An air inlet valve is arranged at the position of the air inlet. The air cylinder of the air cylinder piston mechanism is provided with a reciprocating flow mouth which is provided with a reciprocating flow control valve. The reciprocating flow mouth is communicated with a timing pulse air mechanism through a reciprocating communicating channel. A heat regenerator is arranged on the reciprocating communicating channel. An exhaust air outlet is formed on the air cylinder of the cylinder piston mechanism, and an exhaust valve is arranged at the position of the exhaust air outlet. The combustion chamber is arranged inside the air cylinder piston mechanism. Due to the facts that the combustion motor is combined with the thermomotor, and the air exhausted from combustion motor is regarded as a circular working medium of a thermomotor, the further utility of the waste heat in the exhaust of the engine has the advantages of effectively improving thermal efficiency of the engine, and being simple in structure, strong in practicability, and broad in application prospect.

The invention discloses an hourglass holding device. The hourglass holding device comprises a fixing plate and an hourglass, wherein an upper side wall of the fixing plate is fixedly connected with two vertical fixing plates; side walls of opposite sides of the two fixing plates are fixedly connected with motors; driving ends of the two motors are arranged oppositely, and fixedly connected with fixing rods; the hourglass is located between the two fixing rods; and one end of each fixing rod away from the motors is fixedly connected with the middle of the hourglass. The hourglass holding devicehas the advantages that a coil is driven to move in a magnetic field through sand in order to cut a magnetic induction line, and generate electric current for driving the motors to start and reversethe hourglass, thereby realizing uninterrupted overturning of the hourglass and ensuring reciprocating flow of the sand in the hourglass. An L-shaped rod and a piston are driven to move when a fixingblock and the fixing plates are inclined, thereby realizing the negative pressure in a sucking disk, realizing absorption of the sucking disk on a tabletop, preventing the fixing plates from tilting and falling, and ensuring the safety of hourglass holding.

The present invention discloses a closed electroendosmotic driving method and electro-endosmotic drum. It has two drum cavities in which the electroendosmosis solution is held respectively, said two drum cavities are communicated by means of electroendosmotic column, said drum cavity is covered with drum membrane, in the interiour of drum cavity the electrode is set respectively, and the electroendosmosis solution and electrode are formed into electroendosmotic pump, on two electrodes the current whose polarity is alternatively changed on be passed through, and the integrals of electrolytic quantities of two directions of every cycle are identical, so that the reciprocating flow of electroendosmosis solution in the electroendosmotic column can be formed so as to result in drum membrane vibration to output mechanical vibration as electroendosmotic driving source to form a closed electric driving device. It can be conveniently series-connected, paralellly-connected and combined to form complex driving system.

A refrigeration cycle apparatus 100 includes a low-pressure compressor 113, a high-pressure compressor 101, a radiator 103, a gas-liquid separator 107, an expansion valve 109, an expander 105 and an evaporator 111. The low-pressure compressor 113 and the expander 105 are coupled by a shaft 116, and the low-pressure compressor 113 is driven using power recovered by the expander 105 from a refrigerant. The low-pressure compressor 113 and the high-pressure compressor 101 are serially connected by an intermediate-pressure flow path 114. The gas-liquid separator 107 and the intermediate-pressure flow path 114 are connected by the reciprocating flow path 115. The reciprocating flow path 115 is configured to allow the refrigerant to circulate bidirectionally. It is possible to regulate the refrigerant flow rate in the reciprocating flow path 115 by controlling the opening degree of the expansion valve 109.

The invention creatively provides a double-wall steel hanging box cofferdam system under condition of tidal reciprocating flow in a typhoon area. The double-wall steel hanging box cofferdam system comprises a cofferdam, wherein a leaning pier is arranged on the downstream of the cofferdam, and a pushing device is arranged between the leaning pier and the cofferdam; side anchor platforms are arranged on the two sides of the downstream of the cofferdam correspondingly, meanwhile, an anchor pier is arranged in water on the upstream of the cofferdam, and a ground anchor is arranged on the shore; and the anchor pier, the ground anchor and the side anchor platforms are connected and fixed to the cofferdam through stay cables. According to the double-wall steel hanging box cofferdam system, the construction scheme that the anchor pier in water is combined with the ground anchor on the shore to position the system is adopted, positioning construction is conducted in the mode that a floating crane and an anchor throwing boat are matched with manual hanging cables, the accuracy of positioning control over the cofferdam is guaranteed, the structure is stable, stress is good, and compared withtraditional anchoring positioning construction, the influence on a riverbed is reduced.

The invention discloses a hydraulic interconnection type energy storage and feedback suspension and a using method thereof. An upper cavity and a lower cavity of a left hydraulic cylinder and an upper cavity and a lower cavity of a right hydraulic cylinder of the energy storage suspension are interconnected in the forward direction through an energy feedback hydraulic pipeline. When an automobile travels to a common road surface, the riding comfort is considered first, an interconnection energy feedback loop is closed by switching work oil ports of electromagnetic valves, and the suspension is a hydraulic energy storage suspension. When the automobile travels to a rugged road surface, the work oil ports of the electromagnetic valves are switched, the interconnection energy feedback loop is opened, excessive constraints are reduced, and thus the purpose of removing torsion loads of an automobile body is achieved. Meanwhile, reciprocating flow energy of the left hydraulic cylinder and the right hydraulic cylinder is recycled through the energy feedback hydraulic pipeline, and the energy is converted into electric energy to be used by automobile electrical equipment. The working performance of the suspension under multiple working conditions is effectively improved, energy recycling is achieved, and wide using prospects are achieved.

The invention discloses a wave energy power generation device for two-way acting, and belongs to the field of new energy development. The device comprises a water port, an air energy storage bin, power generation equipment and an impeller machine; the air energy storage bin is a hollow sealed building, is trepanned at the upper end, and is built in a place with more sufficient seaside waves; the water port is formed in the lower part of the air energy storage bin, and is towards the sea wave incoming side; the power generation equipment is mounted above the air energy storage bin; and the impeller machine is mounted in the trepanning place above the air energy storage bin. Through combination of a ratchet and impellers, two impellers with opposite blade directions respectively serve as driving wheels when air currents are sucked in and exhausted from the air energy storage bin, so that rotating shafts are driven to rotate in the same direction under the condition of reciprocating flowing of the air currents, and a generator is driven to continuously rotate to achieve the function of continuous power generation.

The invention discloses a tidal waterway gate pump dispatching method and an ecological restoration for a tidal waterway. The tidal waterway gate pump dispatching method comprises the steps that in the waterway dry season, a gate of a river mouth is closed; in the waterway flood period, when the tide is located at the low tide level, the gate of the river mouth is opened, flood is discharged into the sea, and water flows into the sea in one direction; and in the waterway flood period, when the tide is located at the high tide level, the gate of the river mouth is closed, the flood is discharged into the sea through a pump station, and the water flows into the sea in one direction. According to the tidal waterway gate pump dispatching method, the water gate, the pump station and other water conservancy facilities in the river network area are utilized, the water conservancy facilities are combined with regulation and control measures, reciprocating flow is changed into one-way flow, it is guaranteed that the upstream water body of the waterway is not jacked by the tide, and the discharging speed is increased; meanwhile, the dilution and self-cleaning functions of the water body are improved, the virtuous cycle is formed, the problem that the tidal river network is subjected to dual actions of tide and runoff, and pollutants flow in the river network area in a reciprocating manner is solved, and meanwhile the effect of tidal river section ecological restoration is improved.

The invention discloses a room temperature barocaloric refrigeration machine based on a piezocaloric effect, and belongs to the technical field of refrigeration machines. The refrigeration machine comprises a high-precision high-pressure electric injection pump, a barocaloric element, heat exchange fluid, a cold-end heat exchanger and a hot-end heat exchanger. The phenomena of pressurization heat release and pressure relief heat absorption can be generated due to phase change of a barocaloric working medium under the action of the high-pressure injection pump, and the heat exchange fluid flows in a reciprocating mode between barocaloric refrigeration working media to carry heat and cold. The high-precision high-pressure electric injection pump provides pressure for the barocaloric refrigeration cycle, and the pressure is output constantly. The pressurization mode is liquid pressure, the defect that mechanical pressure transmission is uneven is well overcome, pressurization oil serves as the heat exchange fluid at the same time and makes direct contact with a sample, heat driven by pressure and cold driven by pressure are directly brought into the hot-end heat exchanger and the cold-end heat exchanger to complete the cycle, and heat loss is reduced.

The invention discloses a wave dissipating rectification floating body and a wave dissipating rectification device and method. Inserting grooves and inserting tenons which adapt to the inserting grooves are formed in the corresponding positions of the two sides, in the length direction, of a main body of the floating body, multiple wave dissipating rectification floating bodies are spliced into arow of wave dissipating rectification floating body sets with the proper length through cooperation of the inserting grooves and the inserting tenons, the wave dissipating rectification floating bodysets can be fixedly arranged between one ends of two support extension boats, breakwaters or bank slopes and extend into water, the wave dissipating rectification floating device with the main body back face facing the boats or breakwaters or bank slopes is formed, when waves beat the wave dissipating rectification floating body, the waves are partly converted into the turbulent flow and the wavebreaking flow, the wave reflection is reduced, and sailing and stable berthing of the boats are facilitated; the other parts of the waves penetrate overflow holes, and under the guide effect of a flowdirection control piece, the waves flow downwards in an inclined manner, reciprocated flow is converted into one-way flow, the impact of the waves to the boats, breakwaters or bank slopes can be greatly reduced, and the sailing and stable berthing of the boats can be facilitated.

The invention relates to a three-level buffer working method. A three-level buffer is composed of a leading-level buffer, a middle-level buffer and a tail-level buffer. The leading-level buffer, the middle-level buffer and the tail-level buffer respectively comprise a cylinder which is in the shape of a column. Each cylinder is filled with buffering media. A cylinder cover is arranged at the opened end of the cylinder and seals an opening. A center through hole which extends axially is formed at the central axis of the cylinder cover. A piston rod penetrates through the center through hole and a piston body assembly is arranged at the top end of the piston rod, suitable for carrying out piston motion in the cylinder and matched with the inner wall of the cylinder in a movable and sealed mode. The cylinder of the leading-level buffer forms a piston rod of the middle-level buffer. The cylinder body of the middle-level buffer forms a piston rod of the tail-level buffer. A pressure sensor for detecting pressure of the media is arranged on the right end face of the piston body assembly of the leading-level buffer. When the piston body assemblies of all levels of the buffers perform piston motion, media reciprocating flow in corresponding cylinders is adjusted according to the media pressure detected by the pressure sensor so as to control speed of the piston motion.

The invention discloses a hydraulic automatic tensioning device for a motor head accessory. The automatic tensioning device includes a cylinder body, a piston is arranged inside the cylinder body and separates the cylinder body into an upper hydraulic cavity and a lower hydraulic cavity, wherein the piston is provided with an one-way valve and a damping hole; hydraulic oil passes through the one-way valve and the damping hole and flows back and forth inside the two hydraulic cavities to generate asymmetrical damping; a piston rod is arranged on the piston and stretches out of a sealing unit; the automatic tensioning device is further provided with an air storage chamber formed in the other hydraulic cavity, and the air storage chamber can make up volumetric difference caused between the upper and lower hydraulic cavities by piston motion, so that the hydraulic oil can freely pass through the one-way valve and the damping hole and flow back and forth inside the upper and lower hydraulic cavities to generate the asymmetrical damping. The hydraulic automatic tensioning device for the motor head accessory can avoid belt slip and generation of noise and vibration to make a system function normally and effectively; the radial dimension of the tensioning device is small, so that the device is easy to arrange; the lengthways guiding rigidity of the tensioning device is great, so that eccentric wear is unlikely to happen to the piston and the cylinder body, and the service life is prolonged.

The invention relates to the field of caisson construction, and discloses a combined anchor pier positioning system for caissons on water, which includes two anchor piers arranged parallel to the reciprocating flow direction and symmetrically centered on the caisson, and perpendicular to the reciprocating flow direction and with The caisson is a plurality of side anchors arranged symmetrically to the center. The anchor pier and the side anchors are connected to the caisson by cables. There are multiple auxiliary anchors behind the anchor pier, and each auxiliary anchor is connected to the anchor pier through The cable is connected, and the top of the anchor pier is also provided with a cable take-up system for tensioning the cables between the anchor pier, the caisson and the auxiliary anchor. The invention also discloses a combined anchor pier positioning method for an overwater caisson. The invention can effectively optimize the anchor pier structure and reduce the engineering amount.