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Maintenance

Guidance on care, inspection and emergency measures for safe operation

Elevator Maintenance

Concept of maintenance

Elevator maintenance means all activities, including preventive maintenance such as daily inspections and periodic inspections, and repairs, carried out so that the elevator can be used safely and normally throughout its given service life.

In principle, elevator maintenance is the responsibility of the managing entity, such as the elevator owner, as defined in Article 2, Item 4 of the Elevator Manufacturing and Management Act (hereinafter the "Elevator Act"). However, for efficient performance, maintenance is generally entrusted to a qualified party who carries out this work.

Necessity of maintenance

Since elevators are generally operated by an unspecified large number of users without an attendant, a separate maintenance system is needed to maintain equipment performance. In particular, if faults in the various safety devices such as wire ropes, door switches, door interlocks, brakes and governors are not prevented, safety accidents will result, so maintenance is indispensable for the safety of users.

Therefore, to prevent casualties and property loss arising from elevator operation, partial repairs and modifications, including maintenance of electrical and mechanical performance, and the associated adjustment work should be carried out in a timely manner.

Daily Care & Inspection

Points to note in management

These are points to note in management for the building owner or the person responsible for management.

Appointing a person in charge
Appoint and clearly designate a person in charge of the elevator. The person appointed should clearly know how to contact the relevant departments and what emergency measures to take in an emergency. Also, appoint a deputy in case the person in charge is absent.

Machine room
Always lock the machine room door and prohibit entry by anyone other than the person in charge. Do not place objects that obstruct passage in or near the machine room and its entrance.

Inside the machine room
Make sure snow and rainwater do not leak in through windows or other vents and affect the operating equipment in the machine room (motor, control panel, etc.), and keep a fire extinguisher for electrical fires on hand.

Landing
Place an ashtray at the landing to encourage people not to smoke inside the elevator. When cleaning the landing with water, water getting inside affects normal operation, so take preventive measures in advance.

Inside the elevator
Do not carry long objects using the emergency exit in the elevator ceiling. If moving goods or heavy objects (a piano, etc.) must be carried, place protective panels on the floor and walls before use. Post only printed material related to safe operation inside the elevator.

Importance of daily inspection

  • For safe operation of the elevator and maintenance of its quality
  • To extend the service life of the elevator and for the convenience of users

Checking the operating condition

– Check whether there is any problem with the elevator performing its normal functions.

(1) Operation of landing call buttons

  1. Check that the call button lights up when pressed.
  2. Check that the call button goes out when the elevator arrives.
  3. At the arrival floor, check that the call button light goes out when it matches the direction of the elevator, and stays lit when it is the opposite direction.

(2) Condition of indicators

  1. Check that the floor indicators and travel direction indicators at the landings and in the car are normal.
  2. Check that the hall lanterns at the landings light up normally.

(3) Operation of buttons in the car

  1. Check the operation of the destination floor buttons.
  2. Check the operation of the door open and door close buttons.
  3. Check the operation of the intercom button.

(4) Door equipment
Check the opening and closing operation.

Inspection of safety devices

– Check those functions of the elevator's safety devices that can be checked from outside and that directly affect operation.

(1) Door closing safety device (door anti-trap device)

  1. Check that when the door closing safety device is activated (safety shoe actuated or sensor detection), the door immediately stops closing and opens.
  2. Check that the reaction force of the door closing safety device's pusher is appropriate.

(2) Door open button
The door open button in the car is a safety switch that forcibly opens a door that is closing or closed.

  1. Check that the door opens when the button is operated while the door is closing or closed.

(3) Reopen function of landing call buttons
This performs the same role as the door open button in the car; check its operation.

  1. Check that if the landing call button is pressed while the elevator door is closing, the door stops closing and opens immediately.
  2. Check that it works only for calls in the same direction as the elevator's travel direction.

(4) Lock of the manual operation panel (car operating panel)
The manual operation panel contains various operating switches, and if operated incorrectly by the general public, the risk of an accident is high, so it must always be locked.

  1. Check that the cover of the manual operation panel is closed and locked.

(5) Intercom
The intercom is a device for contacting the outside when passengers are trapped in the elevator due to a power failure or breakdown, and its function is very important.

  1. Check that the intercom is installed so that it can always communicate with the place where the manager is stationed.
  2. The intercom is a very important device; check its operation every day.
  3. Under the inspection standards revised on September 3, 1999, the communication device (intercom) installed outside must either be installed in multiple locations, such as the management office, electrical room or maintenance company office in addition to the security office, or be installed only in the security office with a buzzer and warning light installed near the outside of the security office or at the main floor landing so that it can be easily noticed from outside, operating in conjunction. (Mandatory for new installation sites)

(6) Machine room lock

  1. The machine room is where normal operation of the elevator is controlled and where a running elevator can be made to stop abruptly, stop between floors, be forcibly dropped, etc., so keys must be strictly managed so that no one other than authorized personnel can enter.
  2. Recently there have been many safety accidents and thefts of elevator parts, so particular care must be taken with key management.

Checking performance

– Check whether the elevator operates while maintaining its inherent characteristics.

(1) Door equipment

  1. Check that the door moves without catching.
  2. Check that the door opening/closing speed and dwell time are appropriate.
  3. Check that there is no noise when the door operates.
  4. Check the door sill grooves on each floor for foreign matter and remove it.

(2) Leveling accuracy
– This refers to the height difference between the landing floor and the car floor when the elevator stops.
– If the leveling error is large, there is a risk of accidents when passengers get on and off, so check it frequently. (Appropriate leveling error: within ±10mm)

(3) Shock at starting, deceleration and stopping, and travel vibration and noise

  1. Check for vibration and noise during travel.
  2. Check for shock at starting and stopping.

(4) Overload detection device (overload switch)
– If the elevator is boarded beyond its passenger capacity (full), an alarm must sound, the door must not close, and the elevator must not start.

(5) Landing door interlock

  1. Check whether the landing door opens while the elevator is running, and the opening gap. (If it opens or the opening gap is large, ask the maintenance company for repair)
  2. Check that the landing door can be opened only with the emergency release key.

Emergency Procedures

What to do when the elevator stops due to a sudden breakdown

Measures in the event of an elevator accident

When an accident causing casualties occurs due to an elevator, the owner or manager of the elevator must promptly take the following measures.

  • Necessary measures such as rescuing people
  • Contact 119 rescue (fire station), the maintenance company, etc.
  • Contact the victim's family
  • Report the details of the elevator accident to the elevator inspection agency

Emergency rescue of passengers in the car

On receiving notice of entrapment, immediately contact the maintenance company, go to the site, and tell the trapped passengers that a rescue is under way so that they can wait calmly.

Depending on where the car has stopped, there is a risk that not only the passengers but also rescuers may fall into the hoistway during rescue work, so sufficient caution is required.

If the car sill is 60㎝ or more and less than 120㎝ from the landing sill, open the landing door and car door and rescue by putting a stepladder into the car from the landing.

Rescuing passengers with the manual handle

  1. Turn off the main power switch.
  2. If landing doors on any floor are open, close them.
  3. Check with the trapped passengers that the car door is closed, and tell them that the car will be moved manually.
  4. Operate the brake release lever and fit the manual handle onto the motor shaft or flywheel.
  5. Turn the manual handle slowly to move to the nearest floor.
  6. Remove the handle, open the door, and rescue the passengers.

Measures in case of fire

1. Fire in the building

  • In case of fire, do not use the elevator for emergency escape.
  • Always use the stairs for evacuation, and call all elevators in the building to the evacuation floor, close the doors and stop them.
  • Operate emergency elevators according to their purpose, such as firefighting.

2. Fire in the machine room

  • For a fire in the machine room, fight the fire using an extinguisher for electrical equipment.
  • Turn off the main power switch while keeping in contact with the passengers in the car.
  • If the car stops between floors, rescue the passengers by the method described above.

3. Fire in the hoistway

  • Take care not to be suffocated by smoke generated when electric wires or rail lubricating oil burn.

Measures in the event of an earthquake

  • Elevators may stop during an earthquake, so do not use them for evacuation.
  • After an earthquake of about seismic intensity 3, resume operation after inspection and confirmation of any abnormality by a maintenance technician; for intensity 4 or higher, by a specialist elevator technician.
  • If passengers are trapped due to an earthquake, rescue them by the method described above, and after the rescue is complete, suspend operation until the above inspection and confirmation are finished.

Elevator Safety Devices

Here are the various safety devices installed in elevators.

Overload detection device

Function: When the load (passengers) exceeds the rated load, an alarm sounds and the door opens. The door stays open until the overload is cleared.

If faulty: The excess load is not detected, so the elevator may fall due to overloading. Slipping between the main ropes and the sheave causes uncontrolled operation.

Emergency call device

Function: A device for contacting the outside when passengers are trapped due to a power failure or breakdown

If faulty: In a power failure or breakdown, contact with the outside is cut off and passengers must remain trapped inside the elevator

Emergency light

Function: A backup lighting device that can maintain a brightness of 1 lux or more inside the elevator during a power failure

If faulty: When trapped in the elevator due to a power failure, it is difficult to locate the device for calling outside, and the loss of light causes fear in passengers, who may attempt a reckless escape

Door switch

Function: A door safety device mounted on the car door and drive mechanism that allows the car to start only when the door is fully closed

If faulty: The elevator moves with the car door open

Door interlock

Function: A landing door safety device that prevents the car from running when a landing door is open, and locks the door on floors where the car is not present so that it cannot be opened from outside except with a special key

If faulty: Because the elevator moves with the landing door open, passengers at the landing may fall into the hoistway or be crushed between the elevator and the wall

Electromagnetic brake

Function: A DC electromagnetic type that is always released during operation and is applied as soon as power is cut off when stopping

If faulty: The elevator may move with the brake applied, causing excessive wear of the brake linings and resulting in uncontrolled operation.

Buffer

Function: Installed in the pit to cushion the impact if the elevator falls to the bottom of the hoistway; there are spring and hydraulic types

Door closing safety device (safety shoe)

Function: A device that automatically reopens the elevator door when a passenger or object is caught in it

If faulty: Passengers become trapped between the doors

Safety gear

Function: Connected to the governor rope, it grips the guide rails and stops the car safely if the car exceeds 1.4 times its rated speed

If faulty: If a rope breaks, a free-fall accident occurs

Governor

Function: If the car speed exceeds 1.3 times the rated speed, it operates the overspeed switch and cuts power to the electromagnetic brake to stop the elevator; if the car speed continues to increase and exceeds 1.4 times the rated speed, it grips the governor rope and activates the safety gear

If faulty: When abnormal elevator speed occurs, the safety gear and safety switch fail to operate.

Limit switch

Function: Prevents overtravel of the elevator so that it does not travel above the top floor or below the bottom floor

If faulty: The elevator may pass the top or bottom floor and strike the top of the hoistway or the pit

Rope brake

Function: An emergency braking device that prevents the elevator from slipping or falling by clamping the main ropes when the elevator falls. It is a safety device that prevents the elevator from falling and from starting with the doors open (開門發車) by gripping the main ropes when the braking device operates, in cases where the ropes slip due to reduced friction between the elevator ropes and the traction sheave at the moment passengers get on and off while the elevator is stopped level at a floor with the doors open, or where the elevator slowly slips and moves due to a defect or failure of the braking device, or where the elevator falls in downward travel or upward travel (the counterweight falls downward).