108 results about "Dead centre" patented technology

A method of continually measuring the cetane number of a diesel fuel, the method comprising the steps of:(a) providing a diesel engine having means for selectively supplying at least three diesel fuels to the engine, a first actuator for varying the injection timing of the engine, a second actuator for varying the fuel flow of the engine, and a third actuator for varying the compression ratio of the engine;(b) providing a first supply of a diesel fuel of known cetane number, a second supply of a diesel fuel of different known cetane number and a third supply of a diesel fuel of unknown cetane number to be measured, the third supply being connected to a diesel fuel blending system;(c) in a first cycle selectively and alternately supplying the first, second and third supplies to the diesel engine, and for each supply, controlling the first actuator to achieve an injection timing of a predetermined angle before top dead centre, controlling the second actuator to achieve a predetermined fuel flow and controlling the third actuator to achieve a predetermined diesel fuel ignition delay by varying the compression ratio of the engine;(d) determining the cetane number of the third supply by linear interpolation of the pre-chamber plug positions, corresponding with the respective compression ratio values, for the three supplies; and(e) periodically repeating steps (c) and (d) in further cycles to yield a series of cetane number values of the third supply.

The invention discloses a press machine driven by a servo motor. The press machine comprises a cross beam body and a base, wherein a stand column is connected between the cross beam body and the base; the base is provided with a working platform and a lower die; a sliding block is connected with a transmission mechanism used for driving the sliding block to make reciprocating motion up and down; the transmission mechanism comprises the servo motor arranged on the top of the cross beam body, a zero-backlash elastic coupler, a speed reducer, and a gear mechanism, an eccentric gear and an eccentric connecting rod mechanism which are arranged in the cross beam body; the servo motor is connected with the speed reducer by the zero-backlash elastic coupler; an output gear of the speed reducer is meshed with the gear mechanism; the gear mechanism is connected with the eccentric gear which is connected with the eccentric connecting rod mechanism; the eccentric connecting rod mechanism is connected with the sliding block by a sliding block connector; and the speed reducer is provided with a mechanical brake. The press machine has the advantages that the energy consumption and the maintenance cost are reduced; the stamping motion and the forming force can be freely adjusted and accurately controlled; and full-load bottom dead centre pressure maintaining can be realized on any kinetic characteristic curve of the sliding block.

The invention relates to a method for controlling the compressor sliding block to stop at dead position. Wherein, it uses the rotation coder as the crank angle/block strike sensor of mechanical compressor, to feed collected angle information to the electric cam controller; the controller based on the crank angle information outputs cam signal, based on the passed angle in fixed time of crank to calculate out the crank speed. The invention is characterized in that: based on the brake angles of last two sliding blocks, it finds the incline factor of angle-speed curvature; when the compressor first operates in one sliding block speed, based on said factor, it can find the present brake angle; when the speed is stable, the brake angle will be automatically compensated referring to the shift from last brake angle; the brake angles in different speeds are stored; when the electric cam receives brake signal, based on preset speed to inquire database, and find out present brake angle; when block reaches said brake angle, outputting the brake signal.

A sheet hole punching device has a device frame; a plurality of punching members arranged in first and second groups, and arranged linearly on the device frame; a driving rotation shaft; a driving motor reciprocally rotating the driving rotation shaft; a gear mechanism transmitting a rotation of the driving rotation shaft; cam mechanisms converting the rotational movement; and a motor control device. The gearing mechanism includes drive gears disposed on the drive rotational shaft, and receiving gears disposed on the punching members to engage with the drive gears. The cam mechanisms include cam followers and cylindrical cams. The cylindrical cam has a V-shaped groove cam to reciprocate each of the punching members between an upper dead point and a lower dead point. The punching members are rotated in one direction to punch holes in first sheets, and subsequently rotated in a reverse direction to punch holes in following sheets.

The invention provides a piston-typed engine without crankshaft, moment dead point, or time delay ignition, mainly comprising a cylinder body, a piston, a piston pin, a non-round internal gear, a mainshaft gear, a mainshaft, a cam, a cam roller, etc. When the piston supplies work, the piston pushes the non-round internal gear to move and pushes the mainshaft gear engaged with the non-round internal gear to rotate, and the power is output from the mainshaft; meanwhile, the other mainshaft gears are driven to drive respective non-round gear engaged with the mainshaft gear to move, in order to implement the working cycles of each cylinder of sucking, pressing, bursting, and discharging. As the thrust force of the non-round internal gear is always tangent to a reference circle of the mainshaft gear and the torque is not changed with the rotation angle of the mainshaft gear, the output torque of the mainshaft is improved to the most extent, the torque of the crankshaft is avoided to be changed with the rotation angle of the crankshaft, the work loss caused by moment dead point and time delay ignition are avoided; the conversion rate of the power can theoretically reach 100%; the output torque, the output power of the mainshaft and the power performance of the engine are greatly improved, and the fuel consumption and pollution discharge are reduced by more than a half.

The invention relates to a pneumatic two-position four-way reversing valve. A traditional built-in two-position four-way reversing valve of a pneumatic motor can stop at a dead-point position in the operating process, i.e. an air-inlet cavity of an air-distributing chamber is directly communicated with an air-discharging opening through a slide block to cause a spraying machine to stop working, and a dead-point phenomenon is strictly prohibited to appear on the spraying machine on an automatic spraying flow line. In the invention, aiming at the deficiency, on the basis of a traditional two-position four-way valve, permanent magnets are inlaid in a reversing piston, an upper end-cover hole and a lower end-cover hole, and the dead-point difficult problem of the two-position four-way valve appearing in the reversing process is solved through the change of magnet forces and friction forces.

The invention relates to a cylinder assembly 1 for a longitudinally flushed stroke piston combustion engine and especially to a large-size two-stroke diesel generator moving slowing and flushing longitudinally. The cylinder assembly 1 includes an air cylinder provided with a combustion room 200 and an entrance area 22. A piston 3 moving back and forward long a cylinder axis Z is installed between an upper dead point and a lower dead point in the cylinder 2. And a flushing air entrance 4 is arranged in the cylinder 2 to facilitate to lead the flushing air 4 into the combustion room 200. The cylinder arrangement comprises a piston (3) which is provided as two piece piston. A mantle piston (32) is provided with a piston ring (33), where a main piston (31) is positioned in the mantle piston. A retaining device is provided at a cylinder for the mantle piston. The rinsing air (41) is introduced from an inlet area (22) to a combustion chamber (200) by the rinsing air opening (320) of the mantle piston.

The invention discloses a monorail crane separable toothed rail driving device suitable for a large gradient. The separable toothed rail driving device comprises a driving mechanism, a walking mechanism, a four-bar mechanism, a connecting mechanism, a meshing rail plate and a transition rail plate; the driving mechanism comprises driving motors, meshing gears, bearing rods and a bearing supporting plate; the walking mechanism comprises walking wheels, clamping wheels, a shell and telescopic supporting rods; the four-bar mechanism comprises first rockers, connecting rods, a second rocker and an oil cylinder; and the connecting mechanism comprises a fixing plate, connecting plates and a connecting bolt. When a monorail crane runs to a ramp, the oil cylinder drives the four-bar mechanism in advance to feed the meshing gears into a transition rail, the meshing gear is adjusted to a dead point state, and the telescopic supporting rods are locked. After the monorail crane enters the ramp, the meshing gears are matched with the meshing rail plate mounted on the ramp to provide auxiliary driving for the monorail crane to climb. The driving device overcomes the defect of insufficient power when the monorail crane operates at a large slope, and stable and safe operation of the auxiliary driving device is realized by virtue of the characteristics of dead points of the telescopic supporting rods and the four-bar mechanism.

The invention relates to a double-crank flying shear mechanism with an instinct of automatically eliminating mechanism movement dead points. One of two cranks of the mechanism is movable, and at least two corresponding bearing blocks supporting the moving crank become sliders, and can be driven by the moving crank to move on a body. In order to ensure the sliders to synchronize on one side during movement, a mechanical synchronizer is arranged. An axis of the moving crank is ensured to be always parallel to an axis of the non-moving crank. Therefore, necessary conditions are created for a novel shearing mechanism to easily cross the mechanism movement dead points. The problem that two sets of past shearing mechanisms in specifications cannot cross the mechanism movement dead points easily is solved satisfactorily. The novel fly shear mechanism is mainly used for shearing metal in movement just like the past shearing mechanisms, thereby still belonging to mechanical equipment in the metallurgy industry. Whether or not the related principle of the novel mechanism can be further applied to other occasions is still unclear at present.

The invention provides a super energy-saving engine, which mainly achieves the purpose of saving energy on a large scale while keeping or producing high power in two ways. The first way is that internal energy consumption phenomena, including included angle dispersion, included angle friction and dead point counteraction existing in a traditional crankshaft engine are eliminated through a lever structure or a straight tooth structure; and the second way is that residual energy is recovered, stored and recombined through a resonance phenomenon of a resonance device, and main energy is superposed, accumulated and amplified to achieve the purpose of further saving energy. In the super energy-saving engine, a periodic driving force, which is output by a cylinder part and is the same as or similar to the fixed frequency of a resonant part, acts on a lever or an inertia hammer in a mechanical or electronic control mode, so that the lever or the inertia hammer of the resonant part performs resonant movement; and working is carried out again after a certain resonant movement, namely after the collection, storage and accumulation of certain energy. In the engine, the expansion force and shock wave force generated by the fuel combustion of the cylinder part, and the energy collected and recombined by the resonant part together generate a torque to drive a rotating shaft to rotate at most of the time so as to achieve the purposes of saving force and saving oil.

The invention relates to a method for switching between a degraded mode and a normal mode for establishing the angular position of an internal combustion engine (10) of a vehicle (1), the method comprising the steps of, in degraded mode, detecting the free space and the teeth of the toothed wheel (130) of the crankshaft (13) during the rotation of the crankshaft (13) from the signal generated by the crankshaft sensor (16), establishing the angular positions of the crankshaft (13) corresponding to the minimum rotation speeds of the top dead centres established, and switching to normal mode when, for each top dead centre, the deviation between the angular position of the crankshaft (13) and a reference position is less than a position threshold for at least one revolution of the crankshaft (13).

A structure for preventing the formation of a dead point for a cam wheel includes a driving wheel with a pressing portion provided at one side thereof for pushing a pushed portion of the cam wheel. When the cam wheel is moved over a distance while rotating simultaneously, a cam portion of the cam wheel pushes one end of the swinging piece. When the one end of the swinging piece is pushed to be apart from the outer periphery of the cam wheel, a restoring piece axially pushes the cam wheel back to its original position. A strapping device includes the above structure, a housing, a first transmission assembly, a second transmission assembly and a third transmission assembly. Tensioning of a circular strap, rapid friction bonding and cutting are sequentially performed by the transmissions of the first to third assemblies, respectively.

The invention provides a four-degree-of-freedom parallel mechanism with infinite rotation capability. The four-degree-of-freedom parallel mechanism with the infinite rotation capability is characterized in that the four-degree-of-freedom parallel mechanism comprises a fixed platform, a movable platform and four branch chains arranged between the fixed platform and the movable platform; four driving devices are symmetrically arranged on the fixed platform; the four branch chains are of the same structure, each branch chain comprise a driving arm, an upper connecting rod, a left connecting rod and a right connecting rod; one end of each driving arm is connected with the fixed platform through a revolute pair, the revolute pair is an active driving pair and is driven by one corresponding driving device; and the movable platform comprises a cross, an eccentric wheel shaft, a connecting block A, a connecting rod A, a connecting block B, a connecting rod B, a connecting block C, a connectingrod C, a connecting block D and a connecting rod D. According to the four-degree-of-freedom parallel mechanism with the infinite rotation capability, by means of symmetrically-arranged eccentric wheel mechanisms, the dead points of the eccentric wheel mechanisms are arranged in a staggered mode, the eccentric wheel shafts can smoothly pass through the dead points, and therefore the fact that an end effector can infinitely rotate in the clockwise direction or the anticlockwise direction can be realized.

The invention provides a high-reliability and high-self-locking-capacity calibration mechanism. The high-reliability and high-self-locking-capacity calibration mechanism comprises a driving assembly,an execution assembly and a feedback assembly which are arranged on a base, wherein the driving assembly drives the execution assembly to be opened and closed, the feedback assembly feeds back the rotation angle of the execution assembly, the driving assembly and the feedback assembly are arranged on the two opposite sides of the execution assembly, and the driving assembly is further matched witha brake; the execution assembly comprises a calibration plate, the calibration plate is fixed on a long shaft, and the long shaft is rotationally arranged on the base; and the driving assembly comprises a motor, a first coupler, a crank, a connecting rod, a shifting pin, a stop pin, a torsion spring and a torsion spring fixing seat, and an output shaft of the motor is connected with a crank shaftthrough the first coupler. According to the high-reliability and high-self-locking-capacity calibration mechanism, the dead point principle of a crank and rocker mechanism is ingeniously utilized, and the torsion spring is introduced, so that the following effects can be achieved: the reliability is high, the assembly process is simple, the production efficiency is high, the rigidity is high, theself-locking performance is good, the mechanism is suitable for batch production, the performance is excellent, and the increasing radiation calibration requirements of a space camera can be met.

In the case of a device having a main support (200) and an equipment support (100), the height of which can be adjusted between a first position and a second position relative to the main support (200), and the equipment support (100) in the first position rests on the main support (200) directly or via components connected to the main support, it is provided that the device has a first crank lever (301), wherein the first crank lever (301) is rotatable about a first axis of rotation (361), that a connecting rod (302) is connected to the first crank lever (301) via a first joint (304), and a second joint (305) is connected to the equipment support, that the first crank lever (301) is mounted about a first axis of rotation in a first bearing directly or via a first shaft (303) and the firstbearing (202) is connected to the main support (200), in that the device has a guide (401, 402, 403, 404) for the equipment support (100) in such a manner that the equipment support (100) is guided by means of the guide (401, 402, 403, 404) such that said equipment support is displaceable parallel to the main support (200), that the device has a stop element (310, 721, 722, 723, 724) and a stop (500, 221, 222, 223, 224), that the stop element (310, 721, 722, 723, 724, 725) is connected to the first crank lever (301) or to the connecting rod (302) rigidly or via a second gearing, that the stop(500, 221, 222, 223, 224) is arranged in the main support (200) or is connected to the main support (200), that, by rotation of the first crank lever (301), the equipment support overcomes an upper dead centre when moving from the first to the second position and, upon further rotation of the first crank lever (301), the stop element (310, 721, 722, 723, 724) comes into contact with the stop (500, 221, 222, 223, 224).

The invention discloses an automatic reversing control system for a double-acting cylinder based on travel control. The automatic reversing control system comprises an initial valve, a reversing valve, a pilot valve and a quick jump valve, wherein a first check block is arranged on the top of a valve core of the pilot valve; the first check block is arranged between two collision blocks driven by a cylinder piston rod; a second check block is arranged on the middle part of a valve core of the pilot valve; the second check block is connected with a valve core of the quick jump valve; the valve core of the pilot valve is used for controlling an exhaust loop of a main air channel; the reversing valve is connected with the quick jump valve and the pilot valve through an air channel connector; the initial valve is connected with the reversing valve through an air channel connector; the initial valve is connected with an external controller; the initial valve is used for controlling the main air channel direction needed by the cylinder; meanwhile, the direction of a control air channel is controlled in order that the valve core of the reversing valve, the valve core of the pilot valve and the valve core of the quick jump valve move to initial positions. The control system realizes automatic reversing without any reversing dead point, and initialization of the valve cores can be performed easily after stop, maintenance or transportation, so that accurate action time sequences of the valve cores are ensured, and automatic reversing actions of various frequencies can be adapted to.

The invention provides a special lifting appliance for an automobile floor assembly, and relates to a lifting appliance. The special lifting appliance comprises a lifting point ring, a flexible connecting piece, a lifting frame and a supporting block assembly, wherein the supporting block assembly comprises a supporting block, a supporting block connecting block, a dead point clamp, a dead point clamp connecting pin, an air cylinder and an air cylinder fixing frame; the air cylinder fixing frame is fixedly connected with the lifting frame, the fixed end of the air cylinder is arranged on the air cylinder fixing frame, the extending end of the air cylinder is connected with the dead point clamp connecting pin, the dead point clamp connecting pin is arranged on the dead point clamp, the deadpoint clamp and the supporting block connecting block are arranged on the air cylinder fixing frame through fixing pin shafts correspondingly, and the dead point clamp and the supporting block connecting block are connected through a movable rotating key; and a dead point clamp limiting assembly is arranged on the dead point clamp, and the supporting block connecting block is fixedly connected with the supporting block through a connecting plate. According to the special lifting appliance, a workpiece can be automatically grabbed and released, the labor intensity is reduced, the production efficiency is improved, meanwhile, the safety performance of the lifting appliance can be improved, safety accidents are avoided, and the lifting appliance further has the advantages of being reliable in structure, low in cost and the like, and is easy to popularize and use.

The invention discloses a continuously adjustable air intake duct deflation device. According to the device, a plurality of deflation grooves located in the inner side of a compression face are formed in a front body of an air intake duct, and the two sides of each deflation groove communicate with the outside of the air intake duct; and an opening penetrating through the compression face is formed between the deflation grooves and the compression face and communicates with the deflation grooves. The device further comprises a driving module, wherein the driving module comprises a motor located in an inner cavity and blades located in the deflation grooves, and the blades open or close the deflation grooves through rotation. The air intake duct deflation device is simple in structure, the deflation amount is continuously adjustable, and interference of dead points is avoided; the deflation device is small and exquisite in structure and suitable for a narrow space; the flexibility is high, adjustment within different angle ranges can be carried out only by changing the length of a kinematic pair without a special requirement on the rotating direction; and due to the fact that the rotating angle of the motor can be known, the rotating angle of the blades can be known without an additional sensor for monitoring the rotating angle of the blades.