电梯基础知识-5 电梯的安全系统

1、5 电梯的安全系统Safety system of lift为了保证电梯运行安全、可靠，电梯上设置了许多电气、机械安全保护装置。只要这些安全装置能够正常、有效地起到各自应有的作用，就一定能保证电梯和乘客的绝对安全，做到万无一失。To ensure lift to operate safely and reliably, electrical and mechanical safety devices are mounted on lift. Good function of these safety devices will guarantee the safety of lift and p

2、assengers. 电梯应有的安全措施：Necessary safety devices include:超速保护装置（限速器、安全钳）；Overspeed protection device, such as overspeed governor, safety gear；供电系统断、错相保护（只对交流电梯有效）；Power cut-off, phase-reverse protection, only applicable to AC lift；底坑撞底缓冲器装置（油压缓冲器、弹簧缓冲器）；Buffer in pit, such as oil buffer, spring buffer；

3、超越井道上、下极限工作位置时的保护装置（上、下终端极限）；Protection device for upper and lower final limit in well, such as upper / lower final (terminal) limit；层门联锁与轿门电气联锁装置；Landing door interlock and car door electrical interlock ；井道底坑有通道时，对重应有防止超速或断绳下落的装置（对重侧限速器、安全钳）；Counterweigh should be equipped with device which prevent

4、s overspeed or ruptured rope precipitation, such as overspeed governor and safety gear； 停电或电气系统故障时应有轿厢慢速移动的救援措施（紧急救援设备）；Rescue measures (emergency rescue device) should be provided for car to move slowly in case of power off or electrical failure；8）各类电气安全保护装置（电梯门口的光电开关等）；Various electrical safety pr

5、otection devices (electro-optical switch located at entrance to landing door)；5-1电梯的安全链Lift safety chain将电梯的所有安全部件串在一起形成的安全回路俗称为电梯的安全链。图5-1为 蒂森TCM电梯的安全链，图5-2为奥的斯SPEC60电梯的安全链。 Safety chain is referred to as safety circuit connected by all safety parts. In figure 5-1 is shown safety chain of Thyssen T

6、CM lift; in figure 5-2 safety chain of Otis SPEC60. 5-2 限速器Overspeed governor 5-2-1 限速器功能Overspeed governor function限速器是检测轿厢超速的装置，在电梯正常运行时它不起作用，当电梯运行速度超过其额定速度并达到一定值（即限速器动作速度）时，它就操纵电气开关打开急停回路，使电动机停转并且制动器制动，在此同时或稍后，它将操纵安全钳动作，使轿厢夹持在导轨上，迫使轿厢停下来。所以限速器总是和安全钳连用的，限速器是在电梯超速并达到临界值时起检测及操纵作用，而安全钳则是在限速器操纵下强制使轿厢停

7、住的执行机构。 As a device to test car overspeed, overspeed governor does not function during lift normal operation. It will operate electrical switch to open emergency circuit, making motor stop and engaging brake. Simultaneously or shortly, overspeed governor will operate safety to activate, forcing car

8、to stop by retaining it on guide rails. Therefore, overspeed governor is always used together with safety gear; the former will test and operate when lift runs at overspeed and reaches limit value, while the latter will force car to stop under the manipulation of overspeed governor. 由于电梯速度不同，通过限速器使电

9、梯停止的操作程序也有所不同，当电梯额定速度1.0m/s时，允许在限速器动作操纵安全钳的同时打开急停回路（即限速器动作1和2同时发生，见图5-3 ）当电梯额定速度超过1m/s时，限速器应首先打开急停回路（即动作1）超速在额定速度的115%以下使电梯急停。如果此动作未能使电梯减速，并且超速达到规定值时，则限速器直接操纵安全钳（即动作2）使轿厢夹持在导轨上。Different lift speed results in different operation procedure for car to stop through overspeed governor. For lifts with ra

10、ted speed of less than /s, it is permissible to open emergency circuit while operating safety gear (overspeed governors action 1 and 2 occur simultaneously, as shown in figure 5-3). For lifts with rated of above 1m/s, overspeed governor should open emergency circuit opens first, i.e. action 1 occurs

11、 occurs, making lift execute emergency stop if lift speed exceeds rated speed but below 115% rated speed. If such action fails to decelerate lift and speed limit value is reached, overspeed governor will directly operate safety gear, i.e. action 2 occurs, leaving car retained on rails.5-2-2 限速器种类及工作

12、原理Overspeed governor types and mechanism任何限速器本身都包括三个机械部分，其一是反映电梯运行速度的转动部分；其二是当电梯运行速度达到限速器动作速度时，根据离心力原理将限速器绳夹紧的机械自锁部分。限速器应保证仅在电梯超速下降时起作用，故有安装方向性，绝对不允许装错；其三是限速器钢丝绳下部张紧装置部分。Any overspeed governor consists of three mechanical parts: rotating part to reflect lift speed; mechanical self-locking part which

13、 will clutch overspeed governor rope when lift speed reaches the threshold which activates overspeed governor. Overspeed governor can onlyl guarantee to function when lift is moving downwards at overspeed, therefore direction should be considered when it is installed and wrong installation is not al

14、lowed; tension device part is below overspeed governor rope. 限速器按其动作原理可分为摆锤式和离心式两种。离心式结构的限速器又可分为垂直轴转动型和水平轴转动型两种。目前常用的大多为后者。Overspeed governor is classified into pendular and centrifugal types according to its mechanism.Centrifugal overspeed governor is classified into vertical rotating and horizonta

15、l rotating types. Currently, the former is frequently used. 5-2-2-1 离心式限速器Centrifugal overspeed governor图5-4为这种限速器的典型结构。它的动作原理是，两个绕各自轴转动的甩块由杠杆连接在一起，以保证同步运动。甩块由螺旋弹簧固定。限速器绳轮在垂直平面内转动，如果轿厢速度超过额定速度预定值时，甩块因离心力的作用向外甩开，使超速开关动作，从而切断电梯的控制回路，使制动器失电抱闸。如果轿厢速度进一步增大，甩块进一步向外甩开，并撞击锁栓，松开摆动钳块。正常情况下，摆动钳块由锁栓拴住，与限速器绳间保持一

16、定的间隙。当摆动钳块松开后，钳块下落，将限速器绳夹持在固定钳块上。固定钳块由压紧弹簧压紧，压紧弹簧可利用调节螺栓进行调节。此时，绳钳夹紧了限速器绳，从而使安全钳动作。当钳块夹紧限速器绳使安全钳动作时，限速器绳不应有明显的损坏或变形。In figure 5-4 is shown the typical structure of this overspeed governor. Its mechanism is as follows: two independently rotating fly weights are connected by lever to ensure synchronou

17、s movement. Fly weights are fixed by spiral springs. Overspeed governor sheave is rotating in vertical suface; if car speed exceeds rated speed, fly weight will fly outwards, enabling overspeed switch to activate, cutting off control circuit and making brake engage. Fly weight will fly outwards furt

18、her, bumping bolt and disengaging swinging jaw if car speed is increased further. In normal condition, swinging jaw is bolted by lock pin, keeping specific distance from overspeed governor rope. After swinging jaw is disengaged, jaw will precipitate, clutching overspeed rope on fixed jaw. Fixed jaw

19、is compressed by press spring which can be adjusted by means of adjusting bolts. When rope clip clutches overspeed governor rope, enabling safety gear to activate, no obvious damage or deformation should be found on overspeed governor rope.5-2-2-2离心式锤型限速器Centrifugal hammer overspeed governor 离心式锤型限速

20、器示意图见图5-5，其工作原理为：当轿厢超速下降时，限速器轮在限速器绳与其绳槽间的摩擦力的作用下，转速加快。因而离心锤所受到的离心力相应地也随之增大，并使离心锤绕着销轴转动，重心外移。当离心力增大到一定值时，离心锤上的内凸子将和锤罩上的外凸子相啮合，使锤罩带动偏心叉一起向着轿厢下降方向转动。当转动到偏心叉中的压绳舌与限速器绳接触时，根据自锁原理，压绳舌将限速器掣停，进而带动安全钳动作将轿厢夹持于导轨上。In figure 5-5 is shown the centrifugal hammer overspeed governor whose mechanism is as described

21、as follows. When car is moving downwards at overspeed, overspeed pulley will accelerate under the influence of the friction between overspeed rope and groove. Therefore, centrifugal applied on centrifugal hammer is increased accordingly, enabling centrifugal hammer to rotate around pin shaft and mov

22、ing gravity outwards. When centrifugal increases to a certain value, inner cam on centrifugal hammer will engage with outer cam on hammer cover; hammer caover will drive deflecting fork to move in the direction towards which car decelerates. When press rope tag contacts overspeed governor rope, the

23、former will stop overspeed governor, driving safety gear to retain car on guide rails.5-2-2-3 立轴式球型限速器Vertically axial ball overspeed governor立轴式球型限速器示意图见图5-6。其工作原理为：限速器绳带动限速器旋转，并将其运动传给一对锥齿轮,使其立轴带动一对飞球转动。随着限速器转速的提高，飞球所产生的离心力不断增加。飞球在克服调节弹簧及结构自重沿立轴向下分力的基础上，不断抬高位置。在飞球抬高位置的过程中，杠杆相应地上提，当提到一定位置时，钩子就与偏心块（或

24、楔块）脱离。在偏心块（或楔块）自重和一定的附加重量的作用下，根据自锁原理，使随着电梯一起下降的限速器绳掣停，从而促使安全钳动作，将轿厢夹持在导轨上。限速器轮直径至少是限速器绳直径的30倍。 锤型限速器一般被用在梯速v的低速电梯上，v1.0m/s的快速梯常选用离心式限速器，高梯选用球型限速器。In figure 5-6 is shown tanding axial ball overspeed governor, whose mechanism is as follows: overspeed governor rope drives overspeed governor to rotate,

25、passing on to a pair of cone pulleys, enabling vertical shaft to drive a pair of fly balls. With speed of overspeed governor increasing, centrifugal produced by fly ball will increase. The position of fly ball will be elevated as long as it overcomes adjusting springs and partial force of self weigh

26、t along vertical shaft. With flying balls position elevated, lever will do so accordingly; when reaching a certain position, anchor and deflecting filler (or wedge) will fly. Under the influence of deflecting filler (or wedge) self weight and other additional weight, overspeed governor rope moving d

27、ownwards with lift will be stopped, enabling safety gear to activate and retaining car on rails.Diameter of overspeed governor pulley should be at least 30 times as that of overspeed governor rope.Hammer overspeed governor is generally used in lift with speed of /s or less; while centrifugal overspe

28、ed governor in lift with speed of more than 1m/s, ball overspeed governor in high-speed lift.限速器的动作速度与轿厢速度的关系一般按表5-1进行调整。In table 1 is shown the relation between speed of overspeed governor and that of car.表5-1 Table 1 轿厢额定速度m/sRated speed of car限速器动作速度（最大值）m/sSpeed which activates overspeed governo

29、r (max.)5-2-4 限速器的安装位置Mounting position of overspeed governor 限速器通常安装在电梯机房或隔离层的地面，它的平面位置一般在电梯轿厢的左后角或右前角处。如图5-7所示。限速器绳的张紧轮安装在电梯底坑，限速器绳绕经限速器轮和张紧轮形成一个封闭的环路，其两端通过绳头连接架安装在轿厢架上，与操纵安全钳的杠杆系统相连。张紧轮的重量使限速器绳保持张紧，并在限速器轮槽和限速器绳之间形成一定的摩擦力。轿厢上、下运动时同步带动限速器绳运动从而带动限速器轮转动。 Overspeed governor is generally mounted on the

30、 floor of machine room or of isolating section. From plan view, it is in rear left corner or front right corner, as shown in figure 5-7. Tension pulley of overspeed governor is mounted in pit; overspeed rope travels around overspeed pulley and tention pulley, forming an enclosed circuit. Both sides

31、of rope are mounted on car frame via rope head connecting support and connected with lever system which manipulates safety gear. Tension pulley weight keeps overspeed rope tensioned, producing friction between overspeed governor groove and rope. Car moving upwards and downwards will snychronize over

32、speed governor rope , enabling overspeed governor pulley to rotate.5-3 安全钳Safety gear 安全钳是在限速器的操纵下，使电梯轿厢紧急制动，夹持在导轨上的一种安全装置。任何曳引电梯的轿厢都必须设有安全钳装置，安全钳装置必须由限速器来操纵，在轿厢达到限速器动作时，甚至在钢丝绳断裂的情况下，安全钳应能保证使满载轿厢掣停在导轨上，并能保持静止状态。安全钳装置只有在电梯超速下行时才起保护作用。只有将被掣停在导轨上的轿厢向上提起时方有可能使安全钳复位。Safety gear is a safety device that wi

33、ll retain car on rails after being jerked under the activation of overspeed governor.Any traction lifts should be equipped with safety gear which must be controlled by overspeed governor. If overspeed governor activates, even in case of rope rupture, safety gear should guarantee to jerk car with rat

34、ed load on rails and leave it stationary.Safety gear will not activate unless lift runs at overspeed. Safety gear will not reset until car retained on rail is hoisted.5-3-1 安全钳装置的构成和布置Safety gear device configuration and arrangement安全钳装置设在轿厢架或对重架上，它由 两部分组成，即掣停机构和操纵机构。掣停机构叫安全钳，它的作用是使轿厢或对重掣停，夹持在导轨上。操纵

35、机构是一组连杆系统，限速器通过此连杆系统操纵安全钳起作用。图5-8为安全钳装置的示意图。Mounted on car frame or counterweight frame, safety gear device is composed of jerk and manipulation parts. The former is called safety gear that is used to jerk car or counterweight and retain them on rails; while the latter is a set of lever system throu

36、gh which overspeed governor manipulates safety gear. In figure 5-8 is illustrated safety gear device.安全钳需要由两组，对应地安装在两根导轨处。大多数情况下安全钳安装在轿厢架下梁的下面，但也可以安装在轿厢架上梁的上面。限速器绳两端的绳头与安全钳杠杆系统驱动连杆相连接，电梯在正常运行时，轿厢运动通过驱动连杆带动限速器绳和限速器运动，此时，安全钳处于非动作状态，其制停零件（楔块、偏心块或滚子）与导轨之间保持一定的间隙一般为23mm。当轿厢超速达到限定值时，限速器动作使夹绳钳卡住限速器绳，这时随着轿厢

37、继续向下连杆被同时提起，带动安全钳夹紧零件与导轨接触，而使安全钳钳口同时夹紧导轨，轿厢掣停。在安全钳作用时，装在其连杆系统中的安全开关应在安全钳动作以前使电动机停止运行。Mounted on two rails accordingly, a pair of safety gears are needed. In most cases, safety gear is mounted below the bottom transom of car, but they can also be mounted above the top transom of car. Rope heads on bo

38、th sides of verspeed governor are connected with safety gear driving lever system; for lift in normal operation, car moves by means of driving lever which drives overspeed governor rope and overspeed governor, meanwhile, safety gear remains deactivated, the gap between jerk parts (wedge, deflecting

39、filler or roller) and rail should be 2 -3 mm. When car reaches the speed limit value, overspeed governor will activate to make rope clip retain overspeed governor rope; meanwhile car continues moving downwards and connecting lever is hoisted, driving pin parts of safety gear to contact rail; enablin

40、g safety gear clip to retain rail and jerk car. Under the effect of safety gear, safety switch installed in connecting lever system should make motor stop prior to safety gear activation.5-3-2 安全钳分类及掣停原理Safety gear types and jerk principle电梯上所采用的安全钳种类较多，一般按动作特性和使用的速度范围分类，电梯安全钳可分为瞬时式、渐进式和具有缓冲作用的瞬时式安全

41、钳。There are several types of safety gears in lifts. According to action characteristics and speed, they can be momentary, progressive and momentary with buffer effect types.5-3-2-1 瞬时式安全钳Momentary safety gear这种安全钳也叫做刚性、急停型安全钳。它的承载结构是刚性的，动作时产生很大的制动力，使轿厢或对重立即停止。这种安全钳结构简单，但它的掣停距离很短，一般在30mm以内，因此只适用于速度较低

42、的电梯，否则掣停时减速度过大，将危及人体的安全（人体能承受的瞬时减速度一般在25m/s以下）。Also called rigid and emergency stop safety gear, this safety gear is rigid in structure. When activating, it will produce huge brake force to make car or counterweight stop immediately. Simple in structure, it is characteristic of short jerk distance o

43、f not more than 30mm, therefore, it is only suitable for lifts with low speed; otherwise, high deceleration during jerk will result in personal injury (Normally personal endurance for momentary deceleration should be below 25m/s).。常见的瞬时式安全钳结构有楔型、滚子型和偏心型，它们又分为单面作用双面作用两种。它们的主要区别在于夹紧零件。所有的瞬时式安全钳，无论是楔型、

44、滚子型或偏心型，均利用自锁夹紧原理，即一旦夹紧零件（楔块、滚子或偏心）与导轨发生接触，就不需要任何外力而依靠自锁夹紧作用夹住导轨，由于夹紧零件是刚性支承的，所以夹紧力立即增大到使轿厢停住为止。夹紧力的大小决定于轿厢的速度和重量。According to lift safety regulations, momentary safety gear is used in lifts with speed of not more than /s. Structure of typical momentary safety gear is divided into wedge, roller and

45、partially-centered types, which are also classified into single face and double face applications. Their main difference lies in pinch parts. Self-lock pinch principle is applicable to all momentary safety gear, no matter what type it is. Once pinch parts (wedge, roller or partially-centered) contac

46、t with guide rails, self-lock pinch force is used to pinch rails without any exterior force needed. Since pinch parts are rigid and supportive, pinch force will immediately increase until car stops. Pinch force magnitude is dependent upon car speed and weight.5-3-2-2 渐进式安全钳Progressive safety gear这种安

47、全钳也叫做弹性滑移型安全钳，这种安全钳的掣停力是有控制地逐渐增大或保持恒定值，掣停过程中轿厢将继续滑移一段距离，使掣停速度不致很大。因此这种安全钳适用于额定速度大于0.63m/s的快速和高速电梯。它又分为变制动力和恒制动力两种。变制动力渐进式安全钳一般由限速器直接带动，随着轿厢掣停滑移过程使安全钳逐渐夹紧，同时制动力逐渐增大而使轿厢达到掣停的目的。恒制动力渐进式安全钳一般由杠杆系统操纵，夹持零件能自锁夹紧并由弹簧承载，其特点是在掣停过程中制动力保持恒定，掣停性能良好，所以现代快速和高速电梯的安全钳绝大多数都采用此种结构。Also called elastic sliding safety ge

48、ar, progressive safety gear is characteristic of gradually increasing of keeping jerk force at constant value; during jerk, car continues sliding a distance, enabling jerk speed rather moderate. Suitable for lift with speed of /s or above, this safety gear is classified into viable jerk and constant

49、-jerk types. Viable progressive safety gear is driven by overspeed governor. With car jerking, safety gear will gradually pinch, meanwhile, brake will increase, enabling car to stop.Constant safety gear is controlled by lever system; pinch parts can self-lock and be supported by spring. During jerk,

50、 brake remains constant with good jerk performance; therefore, it is used in fast and high-speed lifts.5-3-3安全钳的安全技术规范Safety technical regulations of safety gear按电梯安全技术规范的规定，安全钳须满足下列要求：According to safety regulations, safety gear must meet the following requirements:5-3-3-1安全钳掣停过程的平均减速度应在0.2之间。g是重力加

51、速度（/s2）。Average speed of safety gear during jerk should be ranging from 0.2 to . g is gravity acceleration (/ s2）.5-3-3-2在轿厢内载荷均匀分布的情况下，安全钳使轿厢掣停后，轿厢地板的倾斜度不超过其正常位置的5%；In case of evenly distributed load in car, after safety gear makes car stop, slant of floor inside car should not exceed 5% of its nor

52、mal position.5-3-3-3安全钳动作之前或同时应有一电气开关切断电梯控制回路，使曳引机停转。此电气开关应是非自动复位开关。An electrical switch cuts off lift control circuit before or as soon as safety gear activates, enabling traction machine to stop rotating. This electrical switch should be non-automatic reset switch.5-3-3-4安全钳夹紧弹簧和受力零件应有足够的强度系数。Safe

53、ty gear pinch spring and parts on which pressure to exert should have enough strength coefficient. 5-3-4 安全钳制动力Safety gear brake安全钳的掣停过程将吸收运动轿厢的全部能量，包括动能和位能。Whole energy of moving car will be absorbed during safety gear jerk process, including dynamic energy and potential energy. 5-1？F 安全钳的制动力（N） F

54、Safety gear brake (N)G1轿厢载重量（Kg） G1 Car load (kg)G0轿厢系统自重（Kg） G0 Car weight (kg)S 掣停距离 S Jerk distance5-3-5 瞬时式安全钳设计的主要数据：Main data for designing momentary safety gear5-3-5-1制动力Brake5-3-5-2夹紧力Pinch5-3-5-3夹紧表面的比压Proportional pressure on pinch surface5-3-5-4自锁夹紧条件Self-lock pinch conditions5-3-6 渐进式安全钳

55、设计的主要数据：Main data for designing progressive safety gear 5-3-6-1制动力Brake5-3-6-2弹簧力Elasticity5-3-6-3夹紧表面的比压Proportional pressure on pinch surface5-3-6-4夹紧表面的摩擦系数Friction coefficient on pinch surface5-3-6-5自锁夹紧条件Self-lock pinch conditions5-4 缓冲器Buffer缓冲器是由于某种原因，轿厢或对重超越极限位置发生蹲底时，用来吸收轿厢或对重动能的制停装置。缓冲器是电梯最

56、后一道安全装置。缓冲器安装在井道底坑的地面上，轿厢和对重的下方。图5-9为缓冲器位置示意图。对应于轿架下梁缓冲板的缓冲器称轿厢缓冲器；对应于对重架下方缓冲板的缓冲器称对重缓冲器。同一台电梯的轿厢和对重缓冲器其结构规格是相同的。For some reasons, when car or counterweight runs by limit position, resulting in “sinking on bottom”, buffer is used as brake device to absorb car or counterweight dynamic energy. As the

57、last safety device for lift, it is mounted on floor of pit in well, below car and counterweight, as shown in figure 5-9. Car buffer is on buffer board below car frame; while counterweight buffer is on counterweight board below counterweight frame. For an individual lift, buffer structure of car is t

58、he same as that of counterweight.5-4-1 缓冲器分类Buffer types缓冲器一般按结构分为弹簧缓冲器(蓄能)和油压缓冲器（耗能）两种（图5-10）。Buffer is classified into spring buffer and oil buffer according to structure, as shown in figure 5-10.5-4-2 弹簧缓冲器Spring buffer弹簧缓冲器受到轿厢或对重的冲击时，依靠弹簧的变形来吸收轿厢或对重的动能。当电梯运行到井道下部时，因断绳或超载等各种原因，使电梯超越底层停站继续下行，但下行的

59、速度未达到限速器动作速度，在下极限开关不起作用的情况下，将撞击设置在底坑的缓冲器。或当轿厢超越最高停站继续上行，上极限开关不起作用的情况下，对重将撞击底坑中的对重缓冲器，缓冲器将吸收轿厢或对重的动能，减缓轿厢或对重对底坑的冲击。弹簧缓冲器一般用于额定速度在1m/s以下的电梯。图5-11所示两种弹簧缓冲器示意图。 When shocked by car or counterweight, spring buffer will deform to absorb energy from car or counterweight. After approaching the lower part of

60、 well, if lift runs by the bottom landing to continue due to rope rupture or overload, meanwhile, neither lift reaches the speed which will activate overspeed governor nor lower limit switch functions, collision will be preset on buffer in pit. When car runs by the top landing to continue and upper