The core structure of an elevator operates through a coordinated system of mechanical and electrical components. At the center is the hoisting system, which includes a motor, traction sheave, and steel ropes. The motor drives the sheave, causing the ropes to move and lift or lower the elevator car.
A counterweight is connected to the car to balance the load, reducing the energy required for operation and improving efficiency. The elevator car and counterweight move along guide rails, which ensure stability and smooth motion.
In addition, the system is controlled by an electrical control unit that manages speed, direction, and stopping accuracy. Safety devices such as brakes and speed governors are integrated into the system to prevent abnormal operation.
Together, these components allow the elevator to move passengers safely, smoothly, and efficiently between floors.
Basic Elevator Structure
Overall elevator structure:
Traction System
Function: Outputs and transmits power to operate the elevator.
Composition: Mainly consists of a traction machine, traction rope, guide sheave, and deflector sheave.
Composition: Consists of a motor + reduction gear + braking device + coupling, etc.
Main Products: Worm gear, helical gear, and gearless synchronous traction machines.
| / | Geared Traction Machine | Gearless Traction Machine | |
| Worm Gear | Helical Gear | ||
| Composition | Motor + Reduction Mechanism + Brake + Traction Sheave | Permanent Magnet Motor + Brake + Traction Sheave | |
| Advantages | ● Large transmission ratio ● Compact structure ● Low noise ● Simple manufacturing |
● High efficiency (90%) ● High load capacity ● Long service life |
● No reduction mechanism, low speed and high torque ● High efficiency, low noise (technical development direction) |
| Disadvantages | ● Low efficiency (70%) ● Prone to wear, short service life |
● High manufacturing cost ● High noise |
● High manufacturing cost ● High cost of related control components |
T1, T2-Tension of the traction ropes on both sides of the traction sheave;
f-Coefficient of friction;
α-Angle of wrap;
Counter-rotation sheave: refers to the movable pulley on the upper part of the car frame and counterweight frame; different traction ratios can be formed by the traction ropes passing around the counter-rotation sheave as needed.
Traction Rope:
Wire Rope: Mainly Φ12 and Φ16, is a Silurian-style external thickened wire rope: 8×(19), i.e., 8 strands, each strand containing 19 wires.
Flat Composite Steel Strip: The steel strip structure changes the arrangement of the wire rope strands, wrapping polyurethane around the horizontally arranged wire rope strands.
Brakes: The brakes can still be used normally after being held for 10 minutes with the car load at 150% and the brake lever engaged.
Guiding System
Function: Restricts the freedom of movement of the car and counterweight, allowing them to move only along the guide rails.
Composition: Primarily consists of guide rails, guide shoes, and guide rail supports.
Guide Rails: Guiding components for the movement of the car and counterweight, composed of steel rails and connecting plates.
Guide Shoes: Guiding devices installed on the car frame and counterweight assembly, guiding the car and counterweight assembly along the guide rails.
Guide Rail Supports: Components fixed to the hoistway wall or crossbeams, supporting and securing the guide rails.
Guide rail length:
Standard guide rail: 5m/rail;
Short rail: 4m/rail, with rail groove and rail tongue;
Cut-off rail: Less than 5m/rail;
Guide rail installation principles:
1. Each guide rail should have at least two supports;
2. Support spacing should not exceed 2500mm;
3. The length of the last guide rail in a machine room should be greater than 2m;
4. The highest point of the guide rail should be set according to the virtual top layer height of the guide rail;
Guide Rail Brackets:
Bracket Types: Primarily uses flat steel bending and angle steel overlapping; available in fixed and adjustable types.
Bracket Dimensions: Divided into car and counterweight guide rail brackets. The maximum length for car guide rail brackets is 500mm, and for counterweight guide rail brackets, it is 600mm. Dimensions exceeding these limits require shaft repair.
Guide Shoe Models:
Mainly divided into sliding guide shoes (SP) and roller guide shoes (RP); guide shoe selection primarily considers elevator speed, rated load, and guide rail model.
Car System
Function: The car body component used to carry passengers or other loads.
Composition: Consists of the car frame and the car body.
Composition: It consists of an upper crossbeam, uprights, and a car base frame.
Upper crossbeam:
Composition: Mainly composed of upper crossbeam plate, safety clamp linkage device, guide shoe, oil cup, rope end cone sleeve, rope end plate, etc.
Upright column: Composition: Mainly composed of upright column, safety clamp, guide shoe, and safety clamp pull rod.
Car Composition: It consists of the car floor, car walls, and car top (suspended ceiling).
Car base frame (lower car base): Composition: consists of a car base frame and a weighing frame.
Car Composition: It consists of the car floor, car walls, and car top (suspended ceiling).
Upper Car Bottom: Composition: Consists of spliced panels, plywood, flooring, upper car bottom frame, car surround, and car door sill.
Car wall Composition: Generally composed of front wall, side wall, rear wall, door light beam.
Car ceiling (suspended ceiling) – The car ceiling is installed above the elevator car to prevent foreign objects or dust from entering the car, and serves as a windproof and protective measure during elevator operation. If the car is not equipped with a suspended ceiling or decoration, the car ceiling also serves as a regular decorative element.
Weight Balancing System
Function: A counterweight device is installed to reduce the power required by the main engine when lifting the car.
Composition: Mainly composed of a counterweight frame, counterweight blocks, guide shoes, buffer seats, and rope end cones.
Counterweight = Car weight + 0.5 × Rated load
Weight Compensation:
Function: When the car approaches the terminal floor, the weight of the main steel wire rope will shift towards either the car side or the counterweight side, generating a large unbalanced force. To ensure traction, a weight compensation device is added to the elevator design.
Compensation Chain: Suitable for elevators with a rated speed not exceeding 105 m/min and a lifting height of less than 140 meters. It consists of metal chain links and a PVC sheath.
Compensation Cable: Suitable for elevators with a rated speed not exceeding 150 m/min and a lifting height of less than 140 meters. It consists of metal chain links, a PVC sheath, and filler.
Counterweight protection device: National standard: The operating area of the counterweight shall be protected by a rigid barrier. The barrier shall extend upward from the floor of the elevator pit by no more than 0.30m to a height of at least 2.50m, and its width shall be at least equal to the width of the counterweight plus 0.10m on each side.
Door system
Function: To seal off the entrances and exits of the landings and the car. Composition: Mainly composed of car doors, door operators, landing doors, door frames, etc.
Car door Composition: The door located at the entrance of the car, consisting of a door panel, car door guide rail frame, car door sill, door operator, etc.
Landing door Composition: The door located at the entrance of the landing, also known as the hall door, consists of the door panel, landing door guide rail frame, landing door sill, etc.
Door frame: A component of the decorative door frame, primarily serving to position the door and ensure that the gap between the frame and the door leaf meets safety standards. (Main types include small door frames, straight large door frames, straight curtain panel door frames, flared door frames, and flared curtain panel door frames)
Door opening type: The door opening type of elevators can be divided into center-opening doors (including two-door and four-door center-opening doors) and side-opening doors (two-door and three-door side-opening doors) according to the direction and number of door panels.
