Elevator accessories and construction

Elevator accessories and construction

Elevator safety protection system equipped with safety protection device in general by mechanical safety protection devices and electrical safety protection device is composed of two parts. Mechanical safety protection devices are mainly speed limiter and pliers, buffer layer, brakes, door locks, car door safety contact, car roof safety window, car roof protective railings, foot protection, etc. But there are some mechanical safety protection devices are often required to cooperate and chain and the function of the electric parts, the reliability of the device can realize the action and effect. For example layer mechanical lock of the door must be with the electric switch link chain elevator accessories. In addition to the already introduced speed limiter and safety gear, buffer, eventually In addition to the end limit protection device, there are other safety protection devices, which are listed below.

- layer, enter the elevator door locks the safety device of the passenger car first come into contact with is the elevator door (door) hall, under normal circumstances, as long as the elevator car is not in place (station), the layer of doors are closed tightly, only after capsules in place (stand) this layer, layer on the door with the door of the cage to follow the open, so layer door lock is very important to the reliability of the safety device, is directly related to the safety of the passengers to enter the elevator first off.

After entering the floor door, passengers will immediately pass through the door and enter the car. However, due to the different speeds of passengers entering and leaving the car, sometimes people will be caught by the door. The door protection device installed on the elevator is designed to prevent passengers from being hurt or caught in the door.

Three capsules, overload protection device passengers from the layer of the door, the door into the capsules, capsules in the number of passengers (or cargo) to load if more than the rated load of the lift, can lift the overload after unsafe consequences or overload is out of control, causes the accident that the elevator overspeed landing. The function of overload protection device is when capsules over rated load, can be a warning signal and make the car can't start the operation, to avoid the unexpected accidents.

Four, capsules at the top of the safe security window is located in the car at the top of a window. When the security window, make the limit switch normally open contacts disconnect, cut off the control circuit, the elevator can not run at this time. When the car stopped in the middle of the two layers of buildings because of malfunction, the driver can through the security window from the car roof to find layer security door. Installation personnel in the installation, maintenance personnel can also be used when dealing with failure safety window. Because the supply is cut off, can prevent access to the car window when the personal injury accidents caused by the elevator suddenly start. When access security window also must first put the elevator stop switch press (if any) or with a key control Turn off the power. For the sake of safety, the driver had better not from the security window, more don't let the passengers out. Because of security window window is small, and we have more than two meters high from the ground, up and down is not very convenient, power failure, on the top of the car was very dark, and there are all sorts of devices, prone to accidents. Also some elevator without security window, this can use the emergency key to open the corresponding layer up and down the car door.

Five, car roof parapet car fence is the elevator maintenance personnel when working at the top of the car safety protection bar, it is important to the elevator accessories. Have a barrier to prevent maintenance personnel because falling carelessly shaft, practice experience, make the guardrail should be paid attention to when set the fence outside and other facilities within the shaft (especially in heavy) to keep a safe distance, both can prevent fall from its peak, and avoid the hand, relies on the guardrail caused personal injury accidents. The maintenance personnel security code can be written in the "standing on the top of the car in the drive, should hold firmly, don't lean on, guardrail" and "capsules and relative motion of the weight and other facilities inside the shaft Hold the words "safe distance" to remind maintenance operators to pay attention to safety.

Six, bottom hole on the heavy side guard gate to prevent people from entering the pit side under the heavy and dangerous, in the pit on the heavy side should be set up between the two guide rail guard, guard height is 1.7 m above, is apart from the ground 0.5 m installed, the width is not less than the heavy rail distance, defend the net space between the two lateral or perforation size, either horizontal or vertical direction measurement, shall be greater than 75 mm.

Seven capsules, baseboard, capsules and stop when capsules (camp) position higher than the floor standing on the ground, the door will make capsules and layer to produce space between the camp, this gap is likely to make passengers' feet stepped into the shaft, personal injury. Therefore, the standard provisions of the state, each capsules to camp must be installed to protect the foot, the width is standing at the entrance of the whole layer width. The height of the vertical part of the foot should be not less than 0.75 m. vertical sections below down into a inclined plane, inclined plane and horizontal plane Angle greater than 60 ° slope in the horizontal plane projection depth of not less than 20 mm. Protect the foot made, 2 mm thick plate The underside of the cage is supported by flat iron to strengthen the mechanical strength.

Eight, hand brake plate with disk driver wheel when you meet a sudden power failure caused by the elevator elevator stops running, and elevator and without a power outage from a running device, and capsules between two layers of the door again, passengers can't out of the cage. This is needed by the maintenance personnel to the room with brake wrench and disk driver round two artificial manipulation tools make capsules nearby dock station level, in order to ease passenger. Brake wrench style, because the elevator brake device of different and different, all is to use it to make the brake of the brake release. Wheel disk driver is used to turn the motor spindle rotavirus tool (some elevator equipped with inertia wheel, also can control the motor rotation). Operation is operated by two people should be cut off power supply first, -- one person operating brake handle, one dish of hand wheel. Two people need to cooperate with good, lest because of the brake of the brake is opened to forbid the handwheel in the elevator due to the heavy weight driving fast capsules. One person to open the brake, a person slowly turn the handwheel to make car to move up, when the car moved close to flat layer position. Brake wrench and disk driver wheel at ordinary times should be put in significant position and red paint should be applied to eye-catching.

Nine, overspeed protection switch for speed is greater than 1 m/s on the elevator speed limiter has overspeed protection switch, before the mechanical action of speed limiter, this switch action, to cut off the control circuit, make the elevator stops running. Some speed limiter installed on two overspeed protection switch, the first switch action make elevator automatically slow down, the second switch to cut off the control circuit. The speed is not more than 1 m/s elevator, its electrical safety switch speed limiter in the latest reached its movement speed and speed limiter.

Overload protection of the traction motor, elevator used in motor capacity is compared commonly big, from a few kilowatts to more than 10 kw. In order to prevent motor overload was burned down and set up after the thermal relay overload protection device. The elevator circuit frequently used JRO series thermal relay is a kind of double metal thermal relay. Two relay hot components in the traction motor respectively, in the main circuit of fast and slow when motor overload over a certain time, namely the current is greater than the rated current of the motor, after a certain time on the bimetallic strip deformation of thermal relay, and disconnect the concatenated contact in safety protection circuit, protect the motor due to the long term Now, thermistors are also buried in the windings of the motor, that is, when overload fever causes resistance value changes, the amplifier puts the ambassador miniature relay to absorb and close, and disconnects its contact in the safety loop, thus cutting off the control loop and forcing the elevator to stop running.

Ten _ general short circuit protection, short circuit protection of elevator control system, is made up of different capacity fuse was waiting for the elevator accessories. Fuse is the use of low melting point, high resistance of metal can't bear the characteristics of large current, which make it fuse, cut off power supply, on the protection of electric equipment. The limit switch for RCIA fuse inserting type, melt for soft lead wire, flake or stick. The elevator in the circuit also adopted the RLI series spiral type fuse and RLS series spiral quick fuse, to protect the rectifier semiconductor components.

Twelve phase sequence, the power supply system and fault protection when the power supply system (lack of) that for some reason cause the phase sequence of three-phase power line with the original phase sequence are different at the same time, has the potential to lift the original direction to the opposite direction, it has greatly the risk of elevator running. At the same time, the motor in the power supply shortage of phase under abnormal operation will lead to motor burn down. The elevator electrical wiring in the phase sequence relay, is used when the line fault phase or phase and phase sequence relay to cut off the control circuit, make the elevator can not run. However, in recent years due to the development of power electronics and ac drive technology, main drive system of the lift used thyristor power supply direct to dc Traction motor and large power device IGBT as the main body of alternating current frequency conversion technology in the ac speed regulating elevator system (VVVF) application, so that the elevator system work is independent of the power supply phase sequence.