Cause of standard section connecting bolt looseness

Cause of standard section connecting bolt looseness are:mixed installation team personnel,without training,technical quality is uneven,not according to the requirements of construction lifter specification operation,safety awareness is weak;For the provincial process,using the hoisting machinery auxiliary conjoined assembled parts installed,or the standard section on the surface of the assembled integral hoisting,after inspection on connection bolt without fastening;Hand after temporary fixed screw bolt acmotor2.blogspot.com tightening,no longer bolt not use gaskets;Fastening bolt tool is simple,did not use professional torque wrench,short of bolt fastening value;Helped wall after completing the first nut bolts,and the scene the cap number is not enough,back cap missing or not tighten. Helped wall bolt hole is too big,did not use more than electric motor cooling fan 100 x 100 mm 60 mm thick steel gasket;Use of ordinary bolt temporarily use does not change in time. Helped wall bolts are mostly use double-headed screw,and no marked strength,use length,double nut can't tighten;Non-standard professional unit self-check,the acceptance is not serious;Daily use do not timely check and tighten,repair,maintenance,lead to loose bolts,etc.

Second,the elevator installation specification requirements Construction lifter standard section is the spine of the elevator,carrying the weight of the machine itself and cargo movement,the hoisting cage depends on the post up and down reciprocating wheel attachment for standard section,so ac motor electric 65kw attached wheel interface connection,enables the wheel to balance force. Wheel and rack and the place such as transmission mechanism of gear meshing size have the higher requirement of its technology,make sure that the standard section pillar tube joint fault status difference,respectively,0.5 mm and 0.3 mm or less,or less at the same time,the adjacent two rack joint along the direction of tooth difference of 0.3 mm or less,along the length of the tooth difference should be 0.6 mm or less.On the standard section of guide rail and rack column for the first time after installation bolt screw die or have a rivet head. Standard section permanent magnet motors for sale function and requirements of each production manufacturer and requiring less random text file,standard and theory of standard section is not detailed,the expression of the usual safety education,safety inspection and technical clarificaiton,less to this requirement. 

Installation and removal of personnel the subconscious thought standard section strong deformation can not easily,but there is no detailed check for standard section of the wall thickness,therefore in the standard section conjoined assembled parts assembly neglected the connecting bolt fastening.Elevator in the process of installation standard section,section of up to 9 meters high adhesion after installation,the installation of the standard section with conjoined assembled parts are,bolt pseudo screw fixation can be buried. Hanging basket load up and down reciprocating motion acceleration is loose easily guide system two guide verticality and guide the error of the centerline of the overlap is greater than 2 mm,influenced by and other forces,at this time would be a counter weight to run a block or thrown,rope,wire rope guide wheel clearance of large and small. Actuator motor after repair,the rotation speed mismatch cause the vibration of hoisting cage and noise increases,hysteresis shouldn't run into events. Elevator conjoined assembled parts installation operation standard section,to the frequent work of elevator running buried the curse. To resolutely put an end to this is not in conformity with the specification requirements of the installation operation,to regulate the behavior of equipment installation and use.

New type of automobile permanent magnet generator and its application prospect

 New type of automobile permanent magnet generator and its application prospect The new permanent magnet generator,automotive development and application At present,the main motor generator is silicon rectifying generator.The main defects such as: magnetic field generated by the electric field winding,rotor field winding burned,break easily,electric consumption,and must be provided by the battery field current to power generation,this is bound to increase the car cost.Silicon rectifying generator with a carbon brush slip ring structure,the slip ring diameter is large,high linear velocity,carbon brush is easy to wear and short service life,high failure rate.The other is a brushless generator,it increases the air gap magnetic field,the magnetic flux leakage,low material utilization,cost is high.Domestic automobile generator is mainly ferrite permanent magnet alternator,power under 200 w,not directly to automotive wiper,heater,electric horn,such as dc power supply,also can't give battery charging.At home and abroad in recent years,with a new generation of rare earth NdFeB permanent magnet materials,transforming traditional claw auto alternator,with high precision control and regulating circuit,the advanced technology of permanent magnet motor generator system.

Such as JFYW series vehicle permanent magnet alternator,USES the ndfeb permanent magnet,compared with the line around the excitation generator,not made of black metal casting (forging) claw pole and the yoke,without excitation coil,without brush and collector ring.Has the features of simple structure,reliable operation,long service life,small volume,light weight,less loss,high efficiency,low cost,and improve the vehicle electrical properties etc,and does not produce interference of on-board electrical appliances,reduce the battery charge and discharge frequency,director of the service life of the battery,the battery completely without electricity or out of the special circumstances of the battery,starter drive car.Since this series generator with low forward unique design,therefore,by the majority of urban transit system and low speed slow for a long time,frequent starting stop users widely recognized and applied. Second,the structure of the permanent magnet generator Automobile permanent magnet generator including casing,rotor,stator and other components.Fixed on the outside of the rotor steel shaft with weak magnetic circle,weak permeability round set has a groove,groove on with permeability and strong permanent magnet blocks,permeability and strong permanent magnet blocks of ratio of 2:1,the number of two pieces of permeability blocks and the clamp in the middle of the a strong permanent magnet blocks,a pair of poles with weak magnetic material between two pairs of magnetic poles apart,each pole of the adjacent opposite polarity.

The generator is suitable for automobile,engineering machinery,such as motor vehicles and stationary power plant as the charging power supply of the power supply.It consists of the excitation of the three-phase permanent magnet synchronous generators,after rectification,the output and parallel to the car battery power supply,electrical equipment at the same time can also to the battery.The generator in the development of not only successfully solves the permanent magnet generator under variable speed and variable load conditions of voltage stability problem,and solved the permanent magnet generator short circuit,fault protection,has high precision,high efficiency,low pressure charging performance is good,the advantages of larger than power,has a broad application prospect.Promote the use of automobile permanent magnet generator,can save a lot of energy,prolong the service life of battery,improve the economic efficiency of operations,but also conducive to the development and utilization of the rare earth resources of our country. Three,the permanent magnet generator technical advantages of the system Magneto's advantage is that it can be in 0 ~ 15000 RPM and high temperature environment to work properly,its motor parts advantages are: (1) no battery power.Because of its rotor is a permanent magnet,without excitation current,as long as the engine driven rotation can generate electricity,save energy,compared with the same volume of excitation generator,can get double the same circumstances,the output power,and when the damage to the vehicle battery power supply system in travel can still work normally,even without the battery,as long as the rocking forward motivation or slide ignition operation can be realized. 

(2) the power supply at low speed performance is good,small voltage regulation.When the power is low,the electromagnetic parameters of the same case,silicon rectifying generator zero current,permanent magnet generator can be exported 3 a ~ 5 a "field current",greatly improve the power water pump performance at low speed.As small leakage,direct axis and quadrature axis armature reaction reactance is small,the armature reaction is weak,so the voltage regulation is small,its external characteristic is relatively flat,high power,output voltage stability is also very good. (3) simple structure,reliable operation,stable performance.Only on the rotor structure of permanent magnet generator shaft,claw pole,wafer type ndfeb,simplify the processing procedure.A 25% reduction in weight compared with the same power generator,prolong the service life of the bearing,and effectively reduce the brush and slip ring friction of radio interference.Permanent magnet generator avoids electrical excitation generator excitation winding is easy to burn,bolt and the problem of carbon brush and slip ring is easy to wear.Electronic regulator and generator etc,make the generator overall realize dc output,small volume,light weight,easy to maintain.The attention of the auto industry.

Induction motor drive system

Asynchronous motor is characterized by simple structure,strong and durable,low cost,reliable operation,low torque ripple,low noise,do not need to position sensor,high speed limit.Induction motor vector control speed regulation technology is mature,the asynchronous motor drive system has obvious advantages,so the earlier was applied in electric vehicle drive system,the current is three phase induction motor still the mainstream of the electric vehicle drive system products,but have been other new type of brushless permanent magnet traction motor driving system is gradually replaced.Biggest disadvantage is that driver circuit is complex,high cost;Relatively permanent magnet motor,induction motor efficiency and power density is low.

2.The brushless permanent magnet synchronous motor drive system Brushless permanent magnet synchronous motor can use cylindrical radial magnetic field structure or disc axial magnetic field structure,due to the power density and high efficiency and magnet prices wide speed range,development prospect is very broad,is a strong competitor in the traction motor of electric vehicle,had been used in a variety of electric vehicles at home and abroad.Built-in permanent magnet synchronous motor,also known as hybrid permanent magnet reluctance motor.The motor on the www.dongfeng-motor.com basis of the permanent magnet torque superposition of the magnetic resistance torque,the existence of the magnetic resistance torque to improve motor overload capacity and power density,and easy to weak magnetic speed regulating,expanding the scope of the constant power operation.Built-in permanent magnet synchronous motor drive system design theory is increasingly perfect and further,with flexible structure,design degrees of freedom,is expected to get high performance,suitable for electric cars,high efficiency,high density and wide speed traction drive.

These cause the attention of the peers in the major car companies,especially the Japanese car company colleague's favor.At present,the American car companies peers in new model design mainly USES the built-in permanent magnet synchronous motor.generator stator Surface;also called permanent magnet

torque motor type permanent magnet synchronous motor,against the built-in permanent magnet

synchronous motor,its weak magnetic speed range is small,low power density.The structure of the motor dynamic response is fast,and is expected to get low torque ripple,suitable for used in automobile electronic servo drive,such as automotive electronic power steering servo motor.Sensorless permanent magnet synchronous motor drive system is currently a hot topic in the research of permanent magnet synchronous motor drive system,will become the development trend of the permanent magnet synchronous motor drive system is one of the potential competitive advantage.Permanent magnet synchronous motor drive system often adopts vector control at low speed,high speed with weak magnetic control.

Several problems about ac servo motor

Several problems about ac servo motor:Q:(A) of the ac synchronous servo,ac asynchronous servo rated speed is related to whether the number?N1 = 60 f / 2 p? Output constant torque under the rated

speed,constant power above rated speed,so the definition of the rated speed is determined by

induction motor sales the mechanical motor itself or drive to decide?,synchronous speed n1 = 60 f / 2 p,asynchronous machine and slip s,n = (1 - s) n1,synchronous machine n = n1,2 p is logarithmic. Definition of weak magnetic speed control is to judge by the driver.Rated speed can be determined by several aspects:synchronous servo's potential height allows the drive current of motor iron core materials,alternating frequency,maximum power under the rated torque motor, The highest temperature rise,etc.,the main or against potential; Asynchronous motor is mainly restricted by material allows the highest frequency and polar logarithmic. The definition of the rated speed of mechanical and,by the motor itself Electrical characteristics.Q (B) :ac,dc servo distinguish whether or not depends on the drive and motor current or voltage between form?But also changes in the current direction of the brushless dc servo? Whether can be understood as contact? Ac servo is based on the principle of the brushless dc servo evolution? pumps Answer:ac servo usually refers to with sine wave driving mode of servo,brushless drive is equal to the number of the commutator is 6 (7) of a brushless dc motor control precision,poor general characteristics at low speed.Has called him the commercial ac servo,only because electricalmotor1.blogspot.com he get rid of the brush,but I'm afraid that features than good ac servo,dc servo has the gap,10000 times the speed of brushless motors are unique Difficult to achieve.