60 results about "Dead centre" patented technology

A vaned hydraulic pump / hydraulic motor has a housing (1) and an impeller (2) which has vanes (3) rigidly fastened thereto or which is provided in the form of a single one-piece part. Situated between the vanes (3), in the body of the impeller (2), are radial channels (4) with reciprocally movable pistons (5) disposed therein. The pistons (5) are movably fastened via rods (6) to a common hub (7), and the axis of rotation of the hub (7) is radially offset from the axis of rotation of the impeller (2). The hub (7) is coupled to the impeller (2) by a universal joint (10) such as to be capable of rotating together with and at the same speed as the impeller. In the body of each piston (5) there is a cavity (5a) which is capable of receiving a hydraulic fluid and which has a compressible element (5b) mounted therein that is variable in volume under the influence of excess pressure arising as the piston (5) passes through top and bottom dead centre.

The utility model relates to the technical field of bipolar plate press machines, in particular to a dynamic error control and compensation mechanism of a bipolar plate press machine, which comprises a main servo motor direct drive transmission gear shaft and a driven eccentric gear, a connecting rod mechanism adopts a toggle rod type structure and comprises a connecting rod, a corner bracket and a lower connecting rod, and the lower connecting rod is connected with a sliding block adjusting screw rod. A sliding block adjusting servo motor drives a worm and a worm gear transmission mechanism, an adjusting nut structure is arranged in a worm gear and forms a connecting pair with an adjusting screw rod, the worm gear rotates to drive the sliding block adjusting screw rod to move up and down so as to adjust the die height of the sliding block, and the sliding block is provided with an inductance type linear displacement sensor. The main servo motor and the sliding block adjusting servo motor are connected with the displacement sensor through the PLC, the mold closing speed and the mold closing position of the mold are monitored and accurately controlled in real time, high-precision adjustment of mold closing of the mold is achieved, and the position of a bottom dead center can be accurately controlled and compensated in real time.

A low-pressure module suitable for large-capacity flow air turbine relates to the field of compressed air energy storage. The invention comprises a low-pressure outer cylinder, a low-pressure inner cylinder, a bearing box, a gas seal assembly and a corrugated joint. The inner and outer cylinders adopt a horizontal middle-embedded structure and are centered by three sets of adjusting shims. The low-pressure outer cylinder and the inner cylinder are provided with symmetric tangential double air inlets, cooperate with the bottom exhaust structure, and the size of a single air inlet is controllable, the flow field is uniform, and the pressure loss is small. The inner and outer cylinders are flexibly connected by the corrugated joint to absorb the thermal expansion difference; the outer cylinder is supported by the gravity of the base frame and provided with an anchor plate to form an expansion dead point. The inner cylinder adopts an integrated cast flow guide ring, the volute is provided with a flow guide rib plate, and the module adopts 4-stage thrust self-balancing blades. The invention solves the problems of large cylinder, poor sealing strength, and unstable shaft system caused by single air inlet under super large flow, has the advantages of high aerodynamic efficiency, good strength and rigidity, stable operation, and low cost, and is suitable for 350MW-660MW air turbine.

An engaging device of a Mass-Interconnect includes an interchangeable test adapter (ITA) and a locking mechanism. The locking mechanism includes a slide movable between an engaged position and a disengaged position, a dual cam including a first cam arm and a second cam arm respectively configured to contact a first slide leg and a second slide leg to drive the slide between the engaged and disengaged positions, and plurality of contact pads disposed on the slide at regions engaged by the dual cam, the contact pads being made of a resilient polymeric material. The contact pads provide elastic compressibility that enables the receiver and ITA to achieve a substantially zero-gap condition at their mating surfaces while the locking mechanism advances into an over-dead-center locked state.

The present invention relates to an alternative two-stroke reciprocating internal combustion engine and power system thereof which eliminates the intake and compression phases of four-stroke Otto engines, and injects the fuel and the oxidising agent at high pressure directly into the combustion chamber or a prechamber at approximately the moment when the piston is at the top dead centre (TDC), using oxygen and / or air as the oxidising agent and hydrogen-based fuels, synthetic fuels, biofuels, alcohols, natural gas and mixtures thereof. At the same time, a spark is applied or combustion is produced by self-ignition, and expansion occurs until the piston reaches the bottom dead centre (BDC). The piston then starts to rise, the mechanically or electrically actuated exhaust valve opens and exhaust is discharged until the TDC is reached again, thereby repeating the cycle.

The invention relates to a sensitive and self-adjusting detection system for inter-row hoes that comprises a motor (1) with a shaft (2), a sensing rod (3) joined to the shaft (2), and a sensor (5) that determines at least one of the following parameters: speed, rotation, angular position or torque of the shaft (2). The system also includes a control element (10) for varying the position of the sensing rod (3), and a control unit (6) that receives signals from the sensor (5), from the control element (10) and, optionally, from other sensors (8, 9). The control unit (6) processes the signals and allows automatic regulation of the position, sensitivity and dead centre of the sensing rod (3), improving weeding precision and adapting operation to the working conditions of the terrain.

The utility model belongs to the technical field of instruments and meters, and relates to a pneumatic motor actuating mechanism which comprises a box body, a driving gear set and a transmission output assembly are rotatably arranged in the box body, and the driving gear set can drive the transmission output assembly. The box body is provided with a pneumatic module and a manual assembly in a matched mode, and the pneumatic module and the manual assembly can respectively drive the driving gear set to rotate. A manual and automatic clutch is arranged on a box cover of the box body and can adjust the axial position of a first-stage driven bevel gear of the driving gear set so that a first driven bevel gear constructed at the upper end of the first-stage driven bevel gear can be meshed with a first-stage driving bevel gear connected with the output end of the pneumatic module. The actuating mechanism is simple and reasonable in structure, safe and reliable to operate and capable of improving undesirable phenomena such as unsmooth action or action dead points; clutch switching is achieved through the manual and automatic clutch, and automatic operation and manual operation do not affect each other.

A transmission for a human-powered vehicle. The transmission has a primary system that includes a transmission case, a crankshaft with cog, a pair of receiver cranks, a pair of connecting rods, a pair of oscillating driver cranks, and a pair of pedals. A secondary biasing system is engaged with the primary system to provide a favorable torque around dead centers of the primary system. The transmission 150 may be configured to transmit power by driveshaft, chain, or belt to drive a wheel or propeller. In a watercraft application, an operator alternatingly applies force to a pair of pedals while seated close to the floor of a kayak 145. Power from the transmission is transmitted through a steerable lower gear case 134 via a propeller to propel the craft. The operator maneuvers the craft by means of a control lever 135 operably connected to the lower gear case by cables 136.

The utility model discloses a protection mechanism for reducing the return stroke friction force of a slotting tool of a mechanism. The protection mechanism comprises a sliding block end shaft seat, a first-stage connecting rod, a second-stage connecting rod, a fixed end shaft seat, an elastic lifting pin, a first nitrogen cylinder and a connecting shaft, wherein the fixed end shaft seat is fixedly connected with the lower die body, one end of the fixed end shaft seat is hinged to one end of the second-stage connecting rod, the other end of the second-stage connecting rod is hinged to one end of the first-stage connecting rod, the other end of the first-stage connecting rod is hinged to one end of the sliding block end shaft seat, and the sliding block end shaft seat is connected with the pulley mechanism and moves in the horizontal direction; the lower dead center position of the protection mechanism is 0.5 mm below the horizontal line of the central shaft, and the first-stage connecting rod and the second-stage connecting rod form an included angle of a preset angle at the upper dead center position; the elastic lifting pin is installed on the lower die base, and the advanced nitrogen cylinder is installed on the floating slotting tool and moves along with the floating slotting tool. The problems that the slotting tool of the mechanism is abraded and the floating slotting tool is blocked in the return stroke can be effectively solved.

The invention relates to a method of combusting a first liquid fuel and a second liquid fuel in an internal combustion piston engine, the first liquid fuel having a lower heating value than the second liquid fuel, wherein - a first liquid fuel is injected into a cylinder of the engine as a main fuel, which brings most of the energy into the process, so that the total amount of first liquid fuel delivered to the cylinder for one combustion stage is divided into at least two partial injections, wherein - the main injection of the first liquid fuel accounts for 70-95% of the total amount of the first liquid fuel, and - the start of the main injection occurs at the latest at 20°CA before the top dead centre position of the piston in the cylinder, - the pre-injection of the first liquid fuel accounts for 5-30% of the total amount of the first liquid fuel, and wherein - the start of the pre-injection occurs at 20-55°CA before the top dead centre position of the piston in the cylinder, and the pre-injection is formed by one injection event, and - a second liquid fuel is injected into the cylinder of the engine as a fuel assisting compression ignition, so that the start of the injection of the second liquid fuel occurs at 1-23°CA before the start of the injection of the main injection of the first liquid fuel.

The utility model discloses a stacked type balance valve which can prevent a double-acting executing element (such as a hydraulic oil cylinder and a hydraulic motor) from moving in an accelerated mode or moving out of control in the load direction when the double-acting executing element is provided with a suspended, pulled or moving load, namely the speed is not consistent with the input oil quantity (pump) (the oil cylinder is broken due to air suction). The load directions of the lifting equipment and the swinging equipment change positively and negatively; the swinging equipment swings over a dead point; as a side effect, when a reversing valve or a direction slide valve control loop leaks at a balance position, an oil cylinder piston can be prevented from accidentally disallowed displacement (two-way pressure maintaining) in the load direction. According to the utility model, the stacked intelligent module is designed, which is very convenient to overhaul, install and process problems. According to the utility model, the two sandwich valves can be quickly disassembled and assembled by adopting the mounting component and the connecting rod, so that the earlier-stage mounting, free combination and subsequent disassembly and maintenance are greatly facilitated.

The utility model relates to the technical field of belts, and provides an eccentric counterweight type high-strength belt dynamic tension balancing device which comprises a rectangular plate, an adjusting rod fixedly installed at the other end of a first spiral spring, a second spiral spring fixedly installed at the other end of the first spiral spring, and a third spiral spring fixedly installed at the other end of the second spiral spring. The adjusting rod is movably embedded in the cylindrical groove; the U-shaped plate is fixedly mounted at the top of the adjusting rod, and a positioning wheel is movably embedded in the U-shaped plate; the two electric push rods are started at the same time, the two sets of positioning rods are pushed to slide in the through holes through the connecting plates, the positioning rods drive the annular plates to slide on the outer surfaces of the positioning wheels through the connecting blocks, the two annular plates move oppositely or oppositely under the action of the electric push rods, adjustment is conducted according to the size of the belt, and the belt is positioned. The belt is prevented from sliding left and right on the outer surface of the positioning wheel, friction of the belt is reduced, and the service life of the belt is prolonged.

An anti-springback operating mechanism comprises a main shaft rotatably arranged on a side plate, the main shaft is used for being connected with a moving contact and can rotate between a closing position and an opening position, the anti-springback operating mechanism further comprises a rotatably arranged blocking piece, and the main shaft is provided with a stop piece rotating along with the main shaft. The blocking piece is provided with at least one blocking part and at least one avoiding part, the blocking piece is provided with an impacting structure and a pushing structure, when the main shaft rotates from the closing position to the opening position, the pushing structure of the blocking piece is driven to push the blocking piece to rotate to enable the blocking part to rotate to an anti-springback position, and when the blocking part is located at the anti-springback position, the pushing structure of the blocking piece is driven to push the blocking part to rotate to enable the blocking part to rotate to the anti-springback position. The blocking part is located on the rotation path of the impact structure when the main shaft rotates from the opening position to the closing position, the blocking part is located between the rotation center of the blocking part and the impact structure, and when the main shaft rebounds during opening, the impact structure abuts against the blocking part to form a dead point so as to prevent the main shaft from rebounding. And inertia is not needed to prevent the main shaft from rebounding.

This invention provides an integrated mechanism for the deployment and retraction of a scissor lift device at its dead point, relating to the field of combined aerospace vehicle technology. It includes a drive unit and a dead-point thrust mechanism, with the drive unit and the dead-point thrust mechanism being drive-driven. The drive unit can drive the dead-point thrust mechanism to lift the rod at the dead point position upwards. The support portion of the dead-point thrust mechanism can slide to accommodate the horizontal movement of the rod, and the support portion also supports the retracted rod of the scissor lift device. The solution provided by this invention offers another driving force when the directions of the scissor lift rod and the driving force coincide. This driving force helps the scissor lift rod cross the dead point position, ensuring normal operation of the scissor lift device, and also supports the retracted rod of the scissor lift device.

The present invention relates to an operating mechanism for a switchgear, comprising: a rotatable output shaft (11) configured to perform a circuit breaking or closing operation of the switchgear by rotation; a rotatable energy storage rod (13) and a spring (4), wherein the energy storage rod (13) is configured to rotate by a motor (1) to drive the spring (4) to be compressed to store energy; and a rotatable drive rod (12) connected to the output shaft (11), rotatably connected to the energy storage rod (13) and freely rotatably connected to the spring (4) to allow ≤60° rotatability between the drive rod (12) and the spring (4) for performing a circuit breaking or closing operation of the switchgear, wherein the spring (4) is configured to release energy during at least one period of the circuit breaking and closing operation of the switchgear to rotate the drive rod (12) after passing through the dead position of the spring (4).

The invention discloses an electric switch driven by a motor, which at least comprises an insulating shell, and a moving contact assembly, a static contact assembly, a motor and a gear assembly which are arranged in the insulating shell, the gear assembly is at least composed of two groups of gears and a turntable, and a fan gear is provided with at least one driving end; the rotating disc is provided with a force bearing end corresponding to the driving end, a reset elastic piece is arranged between two sets of end faces, matched with the rotating disc, of the sector gear, the reset elastic pieces are used for driving the sector gear to rotate and are meshed with the cylindrical gear or the turbine, an idle running angle of at least 20 degrees is arranged between the driving end and the force bearing end, and after the contact passes a dead point in the opening process, the contact is driven to rotate. When the counter-force elastic piece releases energy, the idle running angle of one side of the driving end and one side of the stress end is reduced, the counter-force elastic piece releases energy to drive the moving contact assembly to be quickly bounced off, and the effect that the moving contact assembly and the static contact assembly are quickly opened is achieved. Therefore, rapid arc extinguishing is realized, the electric service life is prolonged, the large-current breaking capacity is improved, and the safety and reliability of products are improved.

A method to adjust an internal combustion engine is described, comprising the steps of: i) controlling a first and second adjustment member so as to adjust a first and second quantity of air in a first and second cylinder provided with a first and second piston; ii) operating a first and second ignition member with a first and second advance angle relative to the first and second top dead centre of the first and second piston; iii) processing a value of one of the amplitudes associated with a respective frequency of a driving member; iv) detecting that the amplitude at a corresponding desired frequency exceeds a threshold value; v) reducing the first advance angle; and vi) increasing the first quantity of air so as to maintain the average value of the resulting torque constant at two complete rotations of said driving member.

The invention relates to an operating mechanism for a switchgear, comprising: a rotatable output shaft (11) configured to implement an opening or closing operation of the switchgear by rotation; a rotatable energy storage rod (13) and a spring (4) wherein the energy storage rod (13) is configured to be rotated by the motor (1) so as to drive the spring (4) to be compressed to store energy; and a rotatable drive rod (12) connected to the output shaft (11), rotatably connected to the energy storage rod (13) and freely rotatably connected to the spring (4) to allow a rotation of < = 60 DEG between the drive rod (12) and the spring (4) for effecting an opening or closing operation of the switchgear, the spring (4) is configured to release energy during at least one of opening and closing operations of the switchgear in order to rotate the drive lever (12) after passing through a dead center position of the spring (4).

The invention relates to a combustion engine comprising cylinders (2) arranged in parallel in a circle around a rotary output shaft (3) and provided with fuel injectors (5), spark plugs (6), gas outlets (7) and pistons attached to longitudinally movable piston arms (8). The piston arms (8) comprise a freewheel (9) on which a gear (10) is mounted, the gear being provided with a series of free-rotation rollers (11) that make contact with helical tracks (20) of a rotor (19) that is solidly connected to the output shaft (3), rotating same. The output shaft (3) comprises a helical ramp section (21) which, during operation of the combustion engine, acts sequentially on the successive piston arms (8), moving same towards top dead centre in a compression cycle or time.

The utility model discloses a foldable supporting leg and an overhead working truck, and belongs to the technical field of overhead working trucks. The supporting leg comprises a first hydraulic cylinder, one end of the first hydraulic cylinder is connected with a transverse leg main arm, and the other end is connected with a transverse leg telescopic arm. The transverse leg telescopic arm is nested in the transverse leg main arm and can slide in the transverse leg main arm; the transverse leg telescopic arm is hinged with the vertical leg; the transverse leg telescopic arm is hinged to a first dead point rod, the vertical leg is hinged to a second dead point rod, and the first dead point rod is hinged to the second dead point rod; the other end of the second hydraulic cylinder is hinged with the first dead point rod; the transverse leg main arm is arranged on the carrying mechanism; when the supporting leg is in a folded state, the first dead point rod and the second hydraulic cylinder are contracted in the hollow structure in the transverse leg telescopic arm, the second dead point rod is contracted in the hollow structure in the vertical leg, and the vertical leg and the transverse leg telescopic arm are jointly contracted in the transverse leg main arm. The dead point structure and the reinforcing ribs are adopted, so that materials and cost are saved, and the overall stability is improved.

The invention relates to the technical field of casting equipment, in particular to precoated sand shell mold casting equipment. The invention provides precoated sand shell mold casting equipment which comprises a base, rolling wheels which are evenly distributed are rotatably connected to the base in the horizontal direction and used for bearing and conveying a lower mold, guide frames which are symmetrically distributed are fixedly connected to the base, and first sliding blocks are slidably connected to the interiors of the guide frames in the vertical direction; an upper die is connected between the symmetrically-distributed first sliding blocks in a horizontal sliding mode, and a support is fixedly connected to the base. The toggle rod linkage mechanism is driven by the cam, so that stable lifting of the upper mold is realized; during mold closing, through rapid approaching and low-speed high-pressure reinforcement, idle stroke is shortened, mold locking force is amplified, and sand shooting leakage is prevented; mold opening is slowly relieved from a dead point, and a shell mold or a mold is prevented from being damaged; the toggle rod is mechanically self-locked after going through the dead point, the motor stops rotating, the mold is still closed, safety and stability are improved, energy consumption is reduced, and the problems that mold opening and closing of traditional equipment are prone to being stuck, and stability is poor are fundamentally solved.

The application discloses a mold assembly for quick locking of an injection molding machine, which comprises a bottom plate, a T-shaped sliding rail, a pressing block, a pressing plate, a fulcrum shaft and a swing lever locking assembly. A fulcrum hinged seat, a lower pusher seat and a rotary adjusting seat are arranged on the upper end surface of the bottom plate. The fulcrum hinged seat is movably hinged with a fulcrum seat arranged on the lower end of the pressing block through the fulcrum shaft. Locking holes connected with the pressing plate are arranged on the two sides of the front end of the pressing block. An upper pusher seat is arranged on the lower end surface of the rear end of the pressing block. The swing lever locking assembly comprises a first Y-shaped swing lever, a second Y-shaped swing lever, an upper hinged shaft, a lower hinged shaft, a middle hinged shaft, a Y-shaped pull rod, an arc-shaped pull rod, a locking sleeve, a first pin shaft, a second pin shaft and a rotary shaft. The swing lever and the lever structure are designed to realize the relaxation and locking functions. The swing lever dead point locking principle is utilized to make the lever completely in the locking state without relaxation. The nut loosening and the clamping loosening are prevented. The pressing stress condition can be timely fed back to the controller, and the mold replacement is fast and efficient.

The present application relates to pumping unit device field, especially crank balance pumping unit parameter estimation method for electric parameter conversion indicator diagram, the present application is by using the corresponding motor torque of upper and lower dead point, according to parameter automatic correction algorithm, automatically corrects crank maximum balance torque, balance phase angle and motor no-load torque, solves the problem that crank maximum balance torque, balance phase angle, motor no-load torque and other parameters are difficult to obtain or inaccurate.

The invention relates to a method (100) which comprises the steps that consist in: - determining (105) an intake pressure in an intake of a combustion chamber; - determining (106), as a function of the intake pressure, a value representative of a nominal compression torque (CPTnom); - determining (107, 108) instantaneous rotational speeds of a crankshaft near a bottom dead centre of an intake phase and a combustion top dead centre; - determining (109) a value representative of an actual compression torque (CPTréel) as a function of the instantaneous rotational speeds; - determining (110) a ratio (R) equal to the value representative of the actual compression torque (CPTréel) / value representative of the nominal compression torque (CPTnom); and - if the ratio (R) is outside a range, applying (111) a correction to the combustion process.

The utility model discloses a fan power control device, and relates to the technical field of power transmission control. The device is used for controlling separation and combination of a clutch and comprises a support, and a separation action structure used for pushing a separation bearing of the clutch is installed on the support. An operating rod is installed on the support in a swinging mode, the operating rod is connected with a wire pulling structure used for pulling the separation action structure, and the separation action structure is connected with a reverse pulling force application structure; the operating rod is locked after the rod side connecting point of the stay wire structure crosses a dead point in the separation swing direction, and a locking position limiting structure is arranged on the support. The power separation and locking device not only realizes power separation and locking, but also facilitates power recombination, and is simple in structure and reliable in use.

There is provided a cutting blade drive apparatus including: cutting blade units including a plurality of cutting blades arranged on a flat surface; a base unit configured to support the cutting blade units overlapping one another; and a drive mechanism supported by the base unit and configured to drive at least one of the cutting blade units to perform cutting operation. The plurality of cutting blades protrude from a circumference of the base unit in different directions. The drive mechanism allows at least one of the cutting blade units to translate drawing a circular orbit with no dead center so that the cutting blades of one cutting blade unit and the cutting blades of another cutting blade unit overlap to perform the cutting operation.

The utility model belongs to the technical field of air-inlet grilles, and relates to an active air-inlet grille capable of realizing self-locking of blades, which comprises the blades, a connecting rod mechanism and a self-locking mechanism consisting of a plurality of groups of connecting rods. The grid blades are self-locked in the skin through a dead point mechanism formed by rotation of two sets of connecting rods in the self-locking mechanism, the self-locking function of the grid blades can be achieved without the need that the motor is in a continuous working state, meanwhile, the grid blades are driven to act through the multiple sets of connecting rods, and state switching between a complete opening state and a complete closing state is achieved. Compared with the prior art, the active air-inlet grille provided by the utility model has the advantages that the whole vehicle domain control is not influenced, an additional motor is not needed, the system development cost is reduced, and the reliability of the mechanism is improved.

The utility model provides a motorcycle which comprises a motorcycle frame, a motorcycle body covering part, a walking system and a support, the support comprises a support installation part, a side support and an extension spring, the side support rotates with the support installation part as the axis so as to be switched between a parking position and a folding position, and the extension spring is connected between the side support and the support installation part. The extension spring is provided with a spring dead point position, and the spring dead point position is located between 60 degrees and 70 degrees of rotation from the folding position to the parking position. Therefore, in the parking process, the dead point position of the spring is located in the stroke range of thrust applied to the side support by a driver and passengers, the side support cannot stop at a certain position between the dead point position and the folding position A due to lack of the elastic force of the spring after passing through the dead point position of the spring, and then the driver and passengers can stop at a certain position between the dead point position and the folding position A in the parking process. The side support can be pushed and pulled from the folding position A to the parking position B more easily, and the use feeling of a driver and passengers can be improved.