宝马E92带有轴平行布置结构的电动机械式助力转向系统（EPS-APA）产品信息培训手册（英文）（可编辑）

宝马E92带有轴平行布置结构的电动机械式助力转向系统（EPS-APA）产品信息 培训 焊锡培训资料ppt免费下载焊接培训教程 ppt 下载特设培训下载班长管理培训下载培训时间表下载 手册（英文）（可编辑） 宝马E92带有轴平行布置结构的电动机械式助力转向系 统(EPS-APA)产品信息培训手册(英文) Aftersales Training - Product Information. Electric power steering with parallel- mounted motor EPS with APA. BMW ServiceThe information contained in the Product Information and the Workbook form an integral part of the training literature of Aftersales Training. Refer to the latest relevant BMW Service information for any changes/supplements to the Technical Data. Information status: October 2006 Contact: conceptinfo@bmw.de2006 BMW AG München, Germany Reprints of this publication or its parts require the written approval of BMW AG, München VS-12 Aftersales TrainingProduct Information. EPS with APA. Electric Power Steering EPS with Parallel-mounted Motor APA A contribution to even more efficient handling dynamicsNotes on this Product Information Symbols used The following symbols are used in this Product Information to facilitate better comprehension and to draw attention to important information. 3 contains information to facilitate better understanding of the described systems and their function1 identifies the end of a note. Information status and national variants BMW vehicles conform to the highest safety and quality standards. Changes in terms of environmental protection, customer benefits and design render necessary continuous development of systems and components. Consequently, this may result in differences between this product information and the vehicles available in the training course. This document relates exclusively to left-hand drive vehicles with European specifications. On right-hand drive vehicles, some controls or components are arranged differently from the illustrations in this Product Information. Further differences may arise as the result of the equipment variants used in specific markets or countries. Additional sources of information Further information on the individual subjects can be found in the following: - Owner's Handbook - BMW diagnosis system - Workshop systems documentation - SBT BMW Service Technology.Contents. EPS with APA. Objectives 1 Reference for practical applications. 1 Models 3 Electric power steering on BMW vehicles 3 Introduction 5 Comparison with current steering systems 5 Motivation and features 7 System overview 9 Mechanical design 9 Electrical system integration 12 Functions 17 Functional integration 17 EPS functions in detail 19 System components 29 EPS components in detail 29 Service information 37 Important points for servicing and repairs 37 Summary 39 Points to remember 39 Test questions 41 Questions 41 Answers to questions 421 Objectives. EPS with APA. Reference for practical applications. This Product Information is intended to be of help in understanding this document. provide you with knowledge about the new For that reason, you should work through electric power steering with parallel-mounted either Please read up on electric power motor APA that is being used for the first time steering systems such as on thethe chapter "Electric Power Steering" in the E85 or R56 beforehand. That basic on the E92. knowledge will help you to document "Background Material on E85 understand this product information. The document serves as preparation for the Suspension and Steering" or training course offered by BMW Aftersalesthe Product Information "Electric Power Training and as an in-depth supplement to the Steering on the R56". content of that course. Previous knowledge about the steering systems used on BMW and MINI vehicles will 11 22 Models EPS with APA Electric power steering on BMW vehicles Deployment strategy Electric power steering EPS is part of a parallel to the steering rack. Following closely package of measures for reducing CO behind there will be as many other 3 Series 2 emissions. Accordingly, it is the aim of the and 1 Series models as possible in order to BMW Group to fit this steering system to as make as large a contribution as possible to the many models as possible. reduction of CO emissions. 2 Until the introduction of EPS and under certain The BMW E85 and E86 already have an EPS peripheral conditions see the section The introduction of EPS starts with system, as does the MINI R56. The E92 330d the E92 330d followed by other 3 "Conditions" those vehicles will retain the Series and 1 Series models. EPS is will be the first model to feature a new version familiar hydraulic power steering system. part of a package of measures aimed of EPS. The electric motor that produces the at reducing CO emissions. 2 power assistance for steering is mounted Conditions EPS will not be available on vehicles with The vehicle order must specify the option certain options or on certain versions of 1CB "ACEA/CO package". This will be 2 vehicles. Factors such as the available space specified by Production Control. and national requirements are among theEPS is also available for right-hand drive possible reasons for such exclusions. Where vehicles. those considerations apply, the conventional hydraulic power steering will be fitted instead The option "Active steering" prevents fitting of EPS. The most important conditions for fitting electric power steering on BMW 3 Series or 1Vehicles with "xDrive" all-wheel drive are Series models are listed below. not fitted with EPS Initially, EPS will only be fitted on European-Vehicles with the specification vehicles that are sold in N46, M57D30T2 or N54 engine will not be European countries. fitted with EPS in the first instance. Variants All 3 Series and 1 Series models will be fitted virtually mirror-image layout of the left-hand with the same version of electric power drive version. steering. All other model-specific differences with take Only for right-hand drive vehicles will there be the form of coding variations in the a version that is visually distinguishable software. 32 43 Introduction. EPS with APA. Comparison with current steering systems Hydraulic and electric power steering systems The main difference between the two types of Otherwise, the basic design of the steering power steering is in the method of generating system is the same e.g. rack-and-pinion the power assistance force that reduces the steering gear for both hydraulic and electric amount of force that the driver has to apply to power steering systems. With the advent of EPS, the method of generating the power assistance the steering wheel. for steering changes from hydraulic The steering characteristics, e.g. amount of to electrical means. Hydraulic power steering systems feature a steering force required, progression of EPS not only enables model- specific adaptation of steering pump that is driven either by a belt running off steering force, feedback from the roadwheels, characteristics, it also offers other the engine or by an electric motor. The pump are subject to strict development advantages for customers, the environment and car manufacturers. is part of a hydraulic system in which it specifications that have resulted in continual In contrast with active steering, generates the fluid pressure/flow that is used optimization of the hydraulic power steering vehicles with EPS do not have a split steering system, which is why EPS to produce the power assistance for steering. systems so far used. In order that BMW can superimpose an additional steering force but not change the owners continue to experience the Electric power steering systems produce the steering angle. outstanding steering characteristics of BMW power assistance force directly by means of vehicles, a comprehensive specifications an electric motor that transmits its torque catalogue was compiled that the new electric either to the steering column or the steering power steering systems have to match up to. gear. Therefore, such systems generally In addition, a vehicle with hydraulic power require extra gearing to connect the electric steering frequently serves as the benchmark motor to the existing steering system for a new steering system. components. Versions of electric power steering The table below categorizes EPS systems onEPS on MINI: the basis of the mounting position of the servo Servo unit on pinion transmission point unit consisting of electric motor and reduction between steering column and steering gearing. rack, also called "pinion EPS" P-EPS EPS on BMW Z4:EPS with APA on BMW 3 Series or 1 Servo unit on upper steering column in Series: passenger compartment, also called Servo unit mounted parallel to steering rack. "column EPS" C-EPS. EPS with APA P-EPS C-EPS Vehicles BMW 3 Series, 1 MINI BMW Z4 Series R56 E85, E86 E9x, E87 Manufacturer ZF JTEKT ZF Type of Brushless DC motor Brushless DC motor Brushless electric motor asynchronous motor Mounting position Parallel to steering rack Pinion at transmission Upper part of steering of electric motor point betweensteering column and reduction column and steering gearing rack Design of reduction Belt and ball screw Worm shaft and gear Worm shaft and gear gearing drive 53 It is only the combination of the latest steering rack that has enabled generation of generation of brushless DC motors with the high steering rack forces that can be transmission of the drive directly to the required on the Series 3 and Series 1 models. Distinction from active steering The electric motor of an EPS system is The steering train of an active steering system capable of superimposing additional force on is split by a double planetary gear. top of the force applied by the driver. The EPS That enables the active steering to alter the is able to determine the level and timing of that steering angle of the roadwheels without it force independently of such factors as the being felt by the driver through the steering engine speed. wheel. The rigid link between the steering wheel and In order that the wheels adopt the total the front roadwheels that it steers remains steering angle produced by the steering wheel unchanged with electric power steering, i.e. position plus the superimposed adjustment, a the position of the steering wheel always bracing force is required: the driver has to hold relates exactly to a position of the front the steering wheel firmly. A servo unit is also roadwheels. required. This can only be of the hydraulic type on active steering systems. Only hydraulic The electric motor in an active steering servo units are currently capable of providing system, by contrast, is capable of the combination of high positioning force and superimposing a steering angle but not a positioning speed. steering force. 63 Motivation and features Reasons for the introduction of electric power steering systems The use of electric power steering provides By contrast, a greater degree of power many advantages for the BMW customer, the assistance is programmed for models whose environment and the BMW Group as the steering characteristics are to be more vehicle manufacturer. comfort-orientated. Interacting with the well-proven suspension With the disappearance of the hydraulic concepts, a unique combination of driving system consisting of pump, hoses, cooler, comfort and dynamics is achieved. The fluid, etc., assembly of the steering on the steering properties e.g. the level of steering production line is more straightforward for the torque assistance and damping can be finely manufacturer. The EPS steering system is tuned by correspondingly programming the supplied as a pre-assembled unit and fitted to electrical system while ensuring optimum the vehicle as such. In addition, the EPS also adaptation to the different vehicle eliminates the environmental hazard of philosophies. hydraulic fluid leakage. Thus, despite the use of identical mechanical Since, in contrast to hydraulic power steering components, the system will be capable of pumps, the electric motor is activated only perfect adaptation to models in both the 3 when required when steering but not when Series and 1 Series. driving straight ahead fuel consumption is Where more precise steering and better reduced and the effective power output of the handling characteristics are desired for a more combustion engine increased. sports-style model, it can be achieved by The example figures below illustrate the reducing the amount of power assistance. difference in power consumption between the Although the driver then has to apply slightly two steering systems. more force to the steering wheel, the feedback from the roadwheels gives the more "direct" feel desired. Power consumption in watts Electric power steering Hydraulic power approximate figures steering Minimum 10 300-400 no steering movement, engine idling imum 1000 2000 73 Features of electric power steering Improved handling dynamicsSteering wheel backlash is reduced by active speed-dependent damping. ThisSteering characteristics perfectly adapted function also reduces the vehicle's to vehicle model tendency to slew in response to abruptActive return centring steering wheel movements made by the driver Linear dynamics benefits of up to 2 kW. Better environmental credentials: Greater driving comfortFuel saving of approx. 0.2 l per 100 kmSteering train isolated from suspension vibration while still transmitting theNo possibility of leakage from the hydraulic important road feedback different road system. surface conditions to the driver Simplifications for the vehicleImproved isolation of interference from the manufacturer road surface less steering judderReduced assembly and inspectionElectronically controlled, speed-dependent complexity at the production plant as the power-assistance e.g. greater when system is supplied as a complete unit parkingReduced range of variants compared to Greater driving safety: hydraulic systems pumps, hoses, steering wheelsServotronic function: EPS assists the driver to hold the correctEasier tuning of power steering assistance line, particularly at high speeds, by providing by programming a lower level of power assistance than at lowHigh future potential: integration between speeds. vehicle systems dynamic driving systems, driver assistance systems 84 System overview. EPS with APA. Mechanical design The electric power steering is an absolutely For comparison, a hydraulic power steering identical fit with the previously used hydraulic system and the new EPS with parallel- power steering as far as the connections mounted motor are illustrated below. between it and the vehicle are concerned. The EPS consists of a steering torque sensor, EPS control unit, electric motor with position sensor, reduction gearing and steering rack which together form a pre- assembled unit. The mechanical links between the EPS system and the vehicle are the same as with a hydraulic power steering system. The EPS has electrical links with the DME, DSC, SZL, CAS and instrument cluster. 1 - Hydraulic power steering on E92 Index Explanation Index Explanation 1 Hydraulic-fluid reservoir 4 Track rod 2 Steering column 5 Hydraulic power steering pump 3 Torsion bar and valve actuator 6 Steering rack 94 2 - Electric power steering with parallel-mounted motor on E92 Index Explanation Index Explanation 1 Steering rack 5 EPS control unit 2 Steering torque sensor 6 Electric motor with position sensor 3 Steering column 7 Reduction gear 4 Track rod 104 3 - EPS rack-and-pinion steering box with parallel-mounted electric motor Index Explanation Index Explanation 1 Ball-screw drive part of reduction 7 Thrust piece gearing 2 Rack 8 Signal and power lead for steering torque sensor 3 Pinion 9 EPS control unit 4 Steering torque sensor 10 Electric motor 5 Gaiter 11 Toothed-belt drive part of reduction gearing 6 Track rod 12 Reduction-gear housing The EPS system essentially consists of the 3 Those components form a pre- following components, which are described in assembled unit often referred to as "EPS detail in the section "System components": steering rack assembly" that can only be replaced as a complete unit. To do so, the unitSteering torque sensor has to be disconnected from the track rodsEPS control unit and the lower end of the steering column. 1Electric motor with position sensor 3 After a new EPS steering rack is fitted, a front wheel and tracking alignment check isReduction gear required Steering rack The commissioning sequence involves coding the EPS to match the vehicle model and the diagnosis function for learning the end-stop positions. 1 114 Electrical system integration Overview of bus system 4 - Bus system overview for EPS on E92 124 Index Explanation Index Explanation CAS Car access system EPS EPS control unit DME Digital engine management JB Junction box module DSC Dynamic stability control Kombi Instrument cluster DSC-SEN DSC sensor SZL Steering column switch cluster with steering-angle sensor The LWS shown in the bus system overview is not part of the EPS system complex. is the overall steering angle sensor, which is a Instead, the EPS uses the signals from the component of the active steering system. This steering-angle sensor integrated in the SZL. 134 System circuit diagram 5 - System circuit diagram for EPS on E92 144 Index Explanation Index Explanation 1 DSC control unit 7 Junction box 2 Steering torque sensor 8 Fuse in boot with redundant back-up power supply for EPS 3 Electric motor 9 Steering column switch cluster with steering-angle sensor 4 Motor position sensor 10 Instrument cluster 5 EPS control unit 11 CAS control unit 6 DME control unit 154 165 Functions. EPS with APA. Functional integration EPS input variables Steering column switch cluster SZL Digital engine management module DME Transmitter Steering column switch EPS offers BMW owners a package cluster with steering-angle Transmitter Digital motor electronics of functions that improve driving comfort and safety. sensor Signal Engine running Those functions are: speed- dependent power steering Signal Steering angle set by assistance, active steering-wheel Transmitted PT-CAN return, active damping of steering driver via wheel backlash and active roadwheel feedback. Transmitted PT-CAN Receiver EPS control unit In the even