26results about How to "Improve rotation efficiency" patented technology

The application discloses a downhole multi-parameter logging device and belongs to the technical field of logging while drilling, comprising a drill collar, a battery module and a circuit module are respectively arranged at the two ends of the inner cavity of the drill collar and are axially fixed through locking modules, a metal centralizer is fixedly arranged in the inner cavity of the drill collar, a plurality of independent centralizing blocks are arranged at the center of the metal centralizer, the drill collar comprises a drill collar body, an antenna housing, a strip-shaped magnetic core and a coil, and stable signal transmission is guaranteed, the battery module comprises annular batteries and butterfly springs, can be replaced on site and has a damping function, the circuit module comprises resistivity, azimuth gamma and inclination measurement modules, is integrally designed and has strong anti-interference performance, the metal centralizer realizes self-adaptive centralizing through centrifugal force and hydraulic damping, and the independent centralizing blocks can compensate temperature errors, the device is stable in structure, is suitable for complex well conditions, is convenient to maintain and can realize accurate and synchronous measurement of multiple parameters, thereby providing reliable data support for logging while drilling.

The utility model discloses a clamping device for metal steel pipe processing, which comprises a steel pipe clamping device, the two sides of the top of the steel pipe clamping device are fixedly connected with support rings, the inner sides of the support rings are rotatably connected with metal rods, and the surfaces of the metal rods are fixedly connected with hold-down rings. A servo motor is started, the servo motor drives a second bevel wheel to rotate, the second bevel wheel drives a first bevel wheel to rotate, the first bevel wheel drives a screw to rotate, the screw drives a lifting plate to move upwards, the lifting plate drives a toothed plate to move upwards, and the toothed plate moves to drive a gear to rotate. The gear rotates to drive the metal rod to turn over, the metal rod turns over to drive the pressing ring to press the steel pipe, the steel pipe can be fully fixed, the steel pipe can be clamped and fixed, follow-up machining and cutting are facilitated, an existing manual clamping mode is replaced, and therefore the efficient and automatic clamping effect is achieved.

The utility model discloses a high-torque-density magnetic transmission speed reducer and a built-in motor of a power-assisted bicycle, and belongs to the power-assisted technology of bicycles. A magnetic transmission speed reducer and a motor in the prior art have the defects of large torque fluctuation, low transmission efficiency, easy magnetic field mismatch, uncontrollable eddy current loss and the like, the magnetic transmission speed reducer comprises a first stator, a first rotor and a modulation ring, the modulation ring is located between the first rotor and the first stator, a first air gap is kept between the modulation ring and the first stator, and a second air gap is kept between the modulation ring and the second stator. A second air gap is kept between the modulation ring and the first rotor, the modulation ring comprises modulation teeth, the total number of the modulation teeth is p2, the number of pole pairs of the first stator magnetic ring is p3, the number of pole pairs of the first rotor magnetic ring is p1, p1 = p2-p3, a magnetic field of the first air gap is coupled with a magnetic field of the second air gap, and rotation from the first rotor is output in a speed reduction mode through the modulation ring. The motor part and the reduction gear realize transmission through magnetic force, thereby improving the motor operation efficiency and reducing the overall noise of the motor.

The utility model provides a cabinet sheet metal part bending device, it includes frame, support frame, pressure seat, bending block, rotating seat, first air cylinder, second air cylinder, forms the stable base through two support frames fixed in frame bottom, and bending block rotatably connects in support frame side department. Two vertical first air cylinders are installed in frame top, and its output end drives pressure seat to move downward. The pressure seat is worn on the guide rod on the support frame, ensures its along vertical direction smooth movement, thereby effectively compresses and closes the sheet metal part and places on the support frame, realizes the accurate positioning and reliable fixation of work piece, and first air cylinder is responsible for vertical compression, and second air cylinder is responsible for driving bending block rotation, and both of them work together to complete bending process, and the device is high in degree of automation, and simple and reliable to operate, reduces manual labor intensity, and is favorable to guarantee bending angle consistency.

The utility model relates to a passivator turnover container cleaning pool which comprises a pool body and a partition plate, a plurality of sets of cleaning structures are arranged on the partition plate, each cleaning structure comprises a rotary cleaning assembly, and each rotary cleaning assembly comprises a rotary shaft rotationally arranged on the partition plate; the spraying modules and the cleaning modules are alternately arranged in the axial direction of the rotating shaft, each spraying module comprises at least two sets of spraying pipes, and the at least two sets of spraying pipes are eccentrically arranged relative to the rotating shaft and evenly distributed around the rotating shaft. According to the utility model, through the arrangement of the rotary cleaning assembly, the eccentrically arranged jet pipe is driven to rotate through jet counter-acting force to form circumferential full-coverage high-pressure fluid flushing, and the inner wall of the container can be subjected to three-dimensional cleaning through fluid impact and mechanical friction at the same time in cooperation with the cleaning modules which are alternately arranged in the axial direction; and especially, residues on the inner wall of a complex structure are thoroughly removed.

The utility model relates to the technical field of vehicle seats, and discloses a vehicle seat convenient to adjust, which comprises a guide rail capable of being used for the vehicle seat, a cushion is slidably connected to the surface of the guide rail, a backrest is hinged to the end part of the cushion, a bottom plate is fixed at the bottom of the cushion, and a telescopic assembly is arranged on the surface of the bottom plate. A supporting mechanism is arranged on the surface of the telescopic assembly and comprises a sliding plate and a supporting plate, the sliding plate is arranged on the surface of the telescopic assembly, the supporting plate is fixed to one side of the bottom of the sliding plate, a driving structure is arranged on the surface of the telescopic assembly, and a grabbing part is arranged on the surface of the driving structure. Through mutual cooperation of the driving structure and the grabbing component, when the device is not used in daily life, the grabbing component can be stored, so that other activities cannot be influenced, when the parts need to be driven to rotate, rescue workers can find a comfortable grabbing mode by unfolding the grabbing component, and the rescue workers can conveniently and rapidly carry out rescue. Therefore, rotating efficiency is improved, and rescue time is shortened.

The utility model provides a glass tube neck pressing device for ampoule bottle preparation, which relates to the technical field of ampoule bottle preparation, and comprises a processing table and a preparation mechanism arranged on the outer side of the end part of the processing table, the preparation mechanism comprises a neck pressing device body arranged on one side of the processing table, a heating box is arranged on one side of the neck pressing device body, a second bevel gear is driven by a motor to rotate, and a series of components such as a first bevel gear, a third bevel gear, a first rotating shaft, a rotating sleeve, a rotating plate and a first gear can be linked to work cooperatively, so that an ampoule bottle does circular motion and autorotation on the inner side of a limiting seat at the same time; by means of the efficient power transmission and multi-component matching mechanism, the rotating efficiency in the ampoule bottle machining process is greatly improved, and a good foundation is laid for follow-up machining operation.

The invention relates to a wiring device for replacing an electric energy meter without power outage, and belongs to the technical field of electric energy meter replacement, the wiring device for replacing the electric energy meter without power outage comprises a box body, a wiring instrument is fixedly connected in the box body, the box body is provided with a storage area, and a connecting mechanism, a puncture deconcentrator and a connecting wire are placed in the storage area; the connecting mechanism, the puncture deconcentrator and the connecting line are matched with the wiring instrument for use, the puncture deconcentrator is used for connecting a power transmission line below the electricity meter, and the connecting line is used for connecting the puncture deconcentrator with the wiring instrument. When the electric energy meter is maintained, the electric energy meter does not need to be replaced in a user side power-off mode, normal electricity utilization of residents in life is ensured, the alternating cost is reduced, the alternating efficiency is improved, the burden of meter replacing personnel is relieved, the meter replacing efficiency is improved, and in the meter replacing process, the meter replacing efficiency is improved. The wiring instrument can display and record electric power data generated in the meter changing process in real time through the display screen, energy loss is reduced, and economic benefits are improved.

The application relates to a deep-sea automatic load-dumping type buoyancy adjusting water tank, which comprises a water tank for adjusting buoyancy, a first through hole and at least one arc-shaped hole communicated with the first through hole arranged at the top of the water tank; a rotary sealing rod arranged in the first through hole, an arc-shaped stopper matched with the arc-shaped hole arranged at the bottom of the rotary sealing rod; and a load-dumping device arranged in the water tank, which drives the arc-shaped stopper of the rotary sealing rod to rotate when the water tank is damaged and filled with seawater, so that the arc-shaped stopper rotates below the arc-shaped hole, the rotary sealing rod is unlocked with the water tank, and the water tank is separated under the action of gravity to reduce the load. When the buoyancy adjusting valve group is damaged, the water tank is filled with seawater, the seawater flows into a water cylinder from a second through hole, the seawater pushes a piston rod to move to one side of a driving assembly, the driving assembly drives a rotating assembly to rotate, the arc-shaped stopper is driven to rotate, the rotary sealing rod and the water tank are in the unlocked state, the water tank is separated under the action of gravity, and the load of a submarine is reduced.

This invention relates to the field of air conditioner technology, specifically to an installation structure, an electrical control box, and an air conditioner. The problem this invention solves is the inability to move the electrical control box within an air conditioner. To address this problem, embodiments of this invention provide an installation structure connected to the electrical control box. The installation structure includes: a connecting part connected to the electrical control box; and a fixing device connected to the connecting part; wherein at least a portion of the fixing device is movable and drives the electrical control box to move.

The utility model discloses a transmission device for a labeling machine, which comprises a labeling machine body, the top of the labeling machine body is fixedly provided with a transmission belt, and the top of the transmission belt is fixedly provided with a support. The twisting disc is firstly rotated, the twisting disc drives the round rod to rotate, the round rod drives the winding wheel to rotate, the winding wheel rotates to drive the steel rope to wind, the steel rope is wound to drive the transverse plate to move upwards, the transverse plate drives the limiting block to move, the pressing roller can move upwards, and then an object is placed at the bottom of the pressing roller. Then a hollow screw sleeve is rotated, meanwhile, a hollow screw rod is controlled by a single hand to avoid rotation, the hollow screw sleeve drives the hollow screw rod to move downwards, the pressing force of a pressing roller can be adjusted through a pressing ring, the label can be conveniently fixed, an existing mode that the label is not fixed and pressed is replaced, and therefore the label can be fixed and pressed; and the tightness between the label and the article is ensured.

The utility model relates to the technical field of servo motor accessories, and discloses a stator wheel structure for a servo motor, which comprises a motor stator, the front end and the rear end of the motor stator are fixedly connected with clamping sleeves, the left end of the motor stator is clamped with a fixed cover, and the left end of the fixed cover is provided with a plurality of heat dissipation holes. Clamping blocks are fixedly connected to the front side and the rear side of the right end of the fixed cover, the outer walls of the clamping blocks are clamped to the inner wall of a clamping sleeve, the clamping blocks and the clamping sleeve are connected through bolts, a plurality of stator slot wedges are formed in the inner wall of the motor stator, and magnet exciting coils are wound around the outer walls of the stator slot wedges. According to the utility model, the two clamping blocks at the right side of the fixing cover are inserted into the clamping sleeve and are matched with the fixing bolts, so that the fixing cover can be installed at the left end of the motor stator, and guiding and limiting effects are achieved for subsequent installation of the motor rotor, so that the installation is more accurate and convenient; meanwhile, the left end of the fixed cover is provided with a plurality of heat dissipation holes for air circulation, and the heat dissipation holes are prevented from affecting normal heat dissipation of the structure.

This application relates to the field of structural construction, and in particular to a prefabricated beam-column structure and its construction method. The prefabricated beam-column structure includes a structural column, a protruding column, multiple limiting rods, a drive disc, and a crossbeam. The protruding column is connected to the periphery of the structural column. Multiple first arc-shaped grooves are formed at the ends of the protruding column away from the structural column, and the ends of the limiting rods are slidably connected to the first arc-shaped grooves. The drive disc is rotatably connected to the ends of the protruding column away from the structural column. Multiple second arc-shaped grooves are formed through the surface of the drive disc. When the drive disc rotates relative to the protruding column, the multiple limiting rods converge or diffuse along the extension directions of the first and second arc-shaped grooves. A limiting groove is formed at the end of the crossbeam. The limiting groove allows multiple limiting rods to pass through. A limiting ring is provided on the inner wall of the limiting groove. A slot is formed on the side wall of the limiting rod for the limiting ring to engage. A limiting mechanism for fixing the rotational position of the drive disc is provided on the side wall of the drive disc. This application improves the problem of inconvenient assembly and disassembly of beam-column structures.

The invention discloses a telescopic flow guide cover of a tidal current energy water turbine, and relates to the technical field of water turbines.The inner flow guide container used for guiding water flow is installed in the flow guide cover, the outer wall of the inner flow guide container is connected with flow guide blades used for guiding the impact direction of the water flow, and a telescopic annular groove is formed in the upper end of a water wheel shaft; the water wheel has the advantages that water flow flows to the guide vanes in a more concentrated mode, the guide vanes can accurately guide the impact direction of the water flow, the water flow impacts the water wheel blades at a better angle and speed, the rotation efficiency of the water wheel blades and the water wheel shaft is improved, and the water wheel is more stable in rotation. The telescopic annular column is pushed by the lifting telescopic rod to move in the telescopic annular groove, the inner flow guide container, the connecting frame and the flow guide cover are driven to ascend together, and the telescopic flow guide cover can optimize the water flow guide effect by adjusting the height of the telescopic flow guide cover and the state of the flow guide blades under the condition of different water levels or different flow rates.

The water soaking mechanism for the steam boiler comprises a boiler body water tank and an air chamber, and the air chamber is fixedly installed on the top face of the boiler body water tank. The steam boiler has the advantages that the reducer pipe and the turbine are adopted, when the steam boiler works, the high-temperature smoke pipe is arranged in the boiler body water tank, water in the boiler body water tank is heated at high temperature, steam is formed by the water and then enters the bent pipe along the air inlet hopper, at the moment, the diameter of the section of the bent pipe is large, and when the steam passes through the reducer pipe, the pipe diameter of the other end of the reducer pipe is reduced; the steam flow speed is increased, so that the steam outlet flow speed of the steam inlet pipe is increased, the blowing efficiency of the turbine is improved, the rotating efficiency of the turbine is improved, the turbine drives the shaft rod and the stirring rod to rotate, water in the furnace body water tank is stirred, and the heat distribution uniformity is improved; the problem that friction loss is increased due to middle force transmission is solved, power output is direct and stable, the stirring efficiency is improved, and then the working efficiency is improved.

This invention belongs to the field of foaming preparation technology, and specifically relates to a preparation device for TPEE foamed composite materials. It includes a base component and a preparation chamber fixed to one side of the upper end face of the base component. The device further includes: a connecting rod rotatably connected to the center of the preparation chamber; a driving mechanism housed inside the base component; a connecting sleeve fitted onto the outer surface of the connecting rod; and stirring components evenly distributed on the outer surface of the connecting sleeve; and a sealing cover plate sealed to the upper end of the preparation chamber, connected to the preparation chamber via bolts. This invention allows the driving mechanism to drive the connecting rod to rotate, facilitating subsequent stirring and mixing of the foamed composite material. The connecting sleeve is connected to the connecting rod via a locking groove, and the top of the connecting rod is restrained and limited by a limiting groove on the inner side of the sealing cover plate, preventing displacement and shaking of the connecting sleeve. This facilitates subsequent maintenance and cleaning of the connecting sleeve after use.

The utility model discloses an aluminum ingot overturning and pushing mechanism for aluminum ingot continuous casting production, and belongs to the field of aluminum ingot production. The aluminum ingot overturning and pushing mechanism used for aluminum ingot continuous casting production comprises a conveyor, a base is transversely arranged in the middle of the conveyor, movable grooves are formed in the two sides of the base, an overturning piece is arranged on one side of the outer portion of the base, and the overturning piece is rotationally connected with the movable grooves through second connecting rods. According to the aluminum ingot overturning device, the problems that in the overturning process of an existing aluminum ingot overturning device, due to direct pushing, a conveyor and the edge position of an aluminum ingot are damaged, the aluminum ingot is prone to being stuck in the overturning process, and equipment is damaged are solved, the aluminum ingot block can be supported in the rotating process through rotation of the overturning piece at the upper end of the base, and the aluminum ingot block is prevented from being damaged. Damage of the aluminum ingot to the conveyor can be reduced through the support, rotation of the overturning piece is matched with transmission of the first contact piece and the second contact piece to the aluminum ingot, and efficient overturning of the aluminum ingot can be achieved.

The wind power generation device comprises an energy storage mechanism and a power generation mechanism arranged at the upper end of the energy storage mechanism. The power generation mechanism comprises a driving assembly, the driving assembly comprises a driving shaft, the upper and lower ends of the driving shaft are provided with fixed rings, the outer side of the driving shaft is provided with a plurality of rotatable fan blades arranged between the upper and lower fixed rings, the lower part of the driving shaft is provided with an extension end, the extension end is rotatably embedded with an adjusting assembly, the adjusting assembly comprises an adjusting disc, an annular partition plate is coaxially arranged in the cavity of the adjusting disc, the hollow disc cavity is coaxially divided into a central circular inner cavity and a peripheral annular outer cavity by the annular partition plate, a plurality of limiting assemblies connected with the lower fixed ring are arranged in the inner cavity, a plurality of counterweight assemblies are arranged in the outer cavity, and a support frame is further arranged. The adjusting disc is rotatably embedded in the support frame and is self-adaptively adjusted, so that the device is more efficient.

The utility model discloses a magnetic stirring rod, include: magnetic core, magnetic core cover, annular support part, first casing, second casing, the magnetic core cover is used for to the magnetic core spacing fixed, first casing with second casing buckling is in the both sides of annular support part and forms the sealed space. The utility model discloses through the magnetic core cover to the magnetic core spacing fixed, and first casing and second casing buckling are in the both sides of annular support part and form the sealed space, and the magnetic stirring rod is contacted with the magnetic force rotating device through annular support part and carries out the rotary motion, has solved the contact surface of the stirring rod and the container bottom in the prior art larger, leads to the friction of the resistance generation and reduces the problem of stirring efficiency, and produces the problem of greater noise simultaneously.

The utility model discloses a high temperature and high pressure resistant petrochemical valve structure which comprises a valve body, a valve ball is arranged in the valve body, a first ceramic coating is arranged on the outer wall face of a ball valve, a valve rod is installed at one end of the ball valve, the other end of the valve rod extends to the outside and is provided with a gear, and pipelines are symmetrically arranged on the two sides of the valve body. The outer wall of the pipeline on one side is thickened to form an annular part, an annular groove is formed in the annular part, a plurality of positioning grooves are formed in one side of the annular groove, positioning blocks are arranged in the positioning grooves, the annular part is sleeved with crown teeth, connecting rods are installed between the positioning blocks and the crown teeth, and a plurality of holding rods are installed on the outer ring faces of the crown teeth. The high-temperature-resistant valve is simple in structure, the high-temperature resistance is improved through the first ceramic coating, the high-temperature-resistant capacity of the valve rod is improved, the joint of the valve rod and the valve cover can be protected through the sealing cylinder, double high-pressure-resistant protection is achieved between the valve rod and the valve cover, and safety is improved.

The utility model discloses a butterfly valve that sealing surface structure is stable, its technical scheme main points are including valve body, the valve seat of being positioned in the valve body, the butterfly plate that can form the sealing with valve seat and drive butterfly plate to rotate the valve stem, be provided with two arc seats that are up and down distribution and all with valve stem coaxial on valve body inner wall, two arc seats all are located the other side of valve stem relative valve seat, be provided with two respectively relative two arc seat outer wall sliding of prevent skew pole on valve stem outer wall, be provided with the close groove of prevent skew pole removal in and be located in the vertical plane of valve seat axis on two arc seat outer wall, make the butterfly plate rotate in the process with valve body inner wall mutual non -interference and after the butterfly plate rotates in place and with valve seat close adhesion through prevent skew pole along arc seat outer wall sliding and to close groove, solved the butterfly plate in the rotation process of existing butterfly plate and caused sealing surface damage and make the problem of poor sealing between butterfly plate and valve seat.

The utility model discloses a protection structure for a light-emitting diode (LED) lampshade, which comprises an LED lampshade assembly, and a mounting tube is arranged at the top of the LED lampshade assembly. The servo motors are started, the servo motors drive the screws to rotate, the screws rotate to drive the synchronous gears to rotate, the synchronous gears drive the synchronous belts to conduct transmission, the synchronous belts rotate to drive the synchronous gears to rotate at the same time, the four screws rotate at the same time, and the screws drive the LED lampshade assembly to move upwards to be stored. Meanwhile, a fixing plate drives a rolling wheel to extrude a synchronous belt, the phenomenon that the synchronous belt and a synchronous gear slide can be avoided, the LED lampshade assembly can be stored in a mounting pipe, the LED lampshade assembly can be fully protected, the existing mode that the LED lampshade assembly is not protected is replaced, and the service life of the LED lampshade assembly is prolonged. Therefore, the LED lampshade assembly can be stored and protected, and the phenomenon that the LED lampshade assembly is damaged is effectively avoided.

The utility model relates to the technical field of tire manufacturing, and discloses tire vulcanizing equipment. Included angles are formed between first air holes in a center ring seat of the tire vulcanization equipment and the axial direction and the circumferential direction of the center ring seat respectively, guide vanes are located in air injection paths of the first air holes, and the air injection direction coincides with the normal direction of the guide vanes. The structure can accurately guide airflow, gas media are decomposed into axial speed and circumferential speed when flowing through the air holes, the axial speed and the circumferential speed synergistically act on the guide vanes, the guide vanes efficiently rotate, the rotating efficiency is improved, high-temperature gas can be evenly guided to all positions of the inner wall of the curing bladder, it is guaranteed that the interior of the curing bladder is evenly heated, and the service life of the curing bladder is prolonged. Therefore, the vulcanization quality is improved. In addition, the turbulent flow assembly is driven by airflow to rotate passively, uniform circulation of gas is achieved under the condition that an additional power source is not added, the structure of equipment is simplified, the manufacturing cost is reduced, and energy loss is reduced.

The invention belongs to the technical field of clutches, and particularly relates to a heat dissipation type fan clutch assembly capable of avoiding dust accumulation. The tops of the driving shafts at the two ends are fixedly connected with a driving plate, the driving shafts are rotationally sleeved with a rear cover, the driving plate is contained in a space between the rear cover and a front cover which are connected in a sealed mode, an oil storage cavity is defined by the top face of the driving plate and the inner wall of the front cover, and multiple concentric circular ring teeth are arranged on the end face, close to the outer edge, of the driving plate. The circular ring teeth on the upper end face and the lower end face are contained in the corresponding front cover tooth grooves and the corresponding rear cover tooth grooves and define meshing cavities, an oil inlet channel communicated with the meshing cavities is formed in the driving plate, and an oil return channel communicated with the meshing cavities and the oil storage cavity is formed in the front cover. According to the invention, accumulated dust and greasy dirt at the joint of the shell and the rear cover body can be automatically cleaned in real time; the rotating stability of the driving shaft can be improved; and oil pollution and tooth groove blockage caused by entering of external impurities can be reduced.

The utility model relates to the technical field of motor homes, and discloses an overturning structure for a motor home and the motor homes. The turnover structure for the motor home comprises a support, a plate body and a pushing wheel, the plate body is rotatably arranged on the support in the first direction, the plate body is provided with a containing position embedded into the support and a using position perpendicular to the support, when the plate body is in the using position, the plate body extends in the second direction, and the second direction is perpendicular to the first direction; the pushing wheel is movably arranged on the support in the second direction, the pushing wheel is driven to move in the second direction, the pushing wheel can make contact with the plate body and be in rolling fit with the plate body, and the pushing wheel abuts against the plate body to rotate. According to the turnover structure for the motor home and the motor home, the overall manufacturing cost and the failure rate of the turnover structure are reduced, the possibility of structural damage to the connecting part of the plate body and the pushing wheel is reduced, the rotating efficiency of the plate body is improved, the service life of the plate body is prolonged, and the operation reliability of the plate body is improved.

This invention provides a valve core and a multi-way valve. The valve core includes: a main body, which has a columnar structure, with multiple cavities distributed on its outer periphery, each cavity opening towards the outside of the valve core; and multiple arc-shaped ribs arranged side-by-side on the solid structure of the outer periphery of the main body, each arc-shaped rib extending circumferentially along the main body. Through the technical solution provided by this invention, the multiple arc-shaped surfaces formed by the outer edges of the arc-shaped ribs form a rotating mating surface along the circumferential direction. The rotating mating surface is in contact with an external rotating limiting surface and rotates within the rotating limiting surface. Compared with the prior art where the rotating mating surface of the valve core is directly in contact with the rotating limiting surface, the contact area between the rotating mating surface formed by the arc-shaped ribs and the rotating limiting surface is smaller than the contact area formed directly between the outer wall of the main body and the rotating limiting surface. This reduces the friction and rotational resistance generated between the valve core body and the rotating limiting surface during rotation, thereby improving the rotational efficiency of the valve core.