Analysis of the overall structure of electric forklifts

1、 Core structure composition

The overall structure of an electric forklift can be divided into the following seven systems, which work together to achieve cargo handling functions:

1. Frame and chassis system

Frame:

Material: Welded from high-strength steel, capable of bearing the weight of the entire vehicle and cargo load.

Function: As a basic platform, it integrates power, hydraulic, and control systems.

Chassis:

Tires: Front drive wheels (solid rubber tires, wear-resistant and puncture resistant), rear steering wheels (polyurethane tires, low rolling resistance).

Suspension system: Simple steel plate springs or rubber buffer blocks, suitable for indoor and outdoor floors.

2. Power system

Battery pack:

Location: Usually installed in the middle or rear of the frame to balance weight distribution.

Type: Lead acid battery (mainstream) or lithium-ion battery (high-end model).

Motor system:

Walking motor: drives the front wheels, DC series excited motor (traditional) or three-phase AC motor (modern).

Hydraulic motor: Independently drives the hydraulic pump to generate high-pressure oil to control the lifting of the fork.

3. Hydraulic system

Hydraulic pump: The gear pump converts the mechanical energy of the motor into hydraulic energy (pressure 10-20MPa).

Control valve group:

Multi way valve: distributes high-pressure oil to the lifting cylinder or tilting cylinder.

Return valve: Ensure that the completed oil is filtered and returned to the oil tank.

Executing Agency:

Lifting cylinder: Push the gantry up, and the fork lifts accordingly.

Tilt cylinder: Adjust the forward/backward tilt angle of the gantry (usually ± 6 °).

Auxiliary devices: filter (purifying hydraulic oil), cooler (controlling oil temperature ≤ 70 ℃).

4. Door frame system

Composition: Inner frame, outer frame, fork, chain, roller.

working principle:

The hydraulic cylinder drives the inner gantry to slide along the outer gantry, and the chain pulls the fork to lift synchronously.

Forks are fixed by hooks or hydraulic clamping devices, and the spacing can be adjusted horizontally.

Type: single-stage gantry (lifting height ≤ 3m), two-stage gantry (lifting height 3-6m), three-stage gantry (lifting height>6m).

5. Steering and driving system

Steering system:

Steering wheel: Connected to the steering motor, the rear wheel direction is controlled through gear transmission.

Steering bridge: Adopting Ackermann steering geometry, the minimum turning radius is usually 1.5-2.5m.

Driving system:

Drive axle: Integrated walking motor, reducer, differential, transmitting power to the front wheels.

Braking system: hydraulic disc brake (front wheel) combined with electromagnetic brake (motor reverse drag brake).

6. Control system

Electronic Control Unit (ECU):

Function: Receive operation commands (accelerator pedal, joystick signals), and control motor speed and torque through pulse width modulation (PWM).

Battery management: monitoring battery level and temperature, supporting energy recovery (converting kinetic energy into electrical energy during braking to recharge the battery).

Operation interface:

Control lever: controls the lifting, tilting, and gantry movement of the fork.

Accelerator pedal: Adjust the driving speed and switch forward/backward with the direction switch.

safeguard:

Fault diagnosis: Real time monitoring of motor temperature, battery voltage and other parameters, automatic shutdown and alarm when exceeded.

Overload protection: Cut off abnormal current to prevent motor burnout.

7. Safety and auxiliary devices

Protective structure:

Operator protective structure (ROPS/FOPS): Complies with ISO 6055 standard to prevent rollover or falling object injuries.

Roof Guard: A metal frame structure that protects the operator's head.

Lighting and Signal:

Headlights: LED light source, illumination ≥ 200lux (5m distance).

Turn signal, brake light, reverse light: high brightness LED, in compliance with road traffic regulations.

Intelligent assistance:

Reverse camera/radar: detects obstacles behind and emits sound and light alarms.

OPS system: Automatically cuts off power when the operator leaves the seat to prevent misoperation.

2、 Structural layout characteristics

1. Weight distribution optimization

Battery pack position: Installed in the middle or rear of the frame, it forms a balance with the fork load, lowers the center of gravity, and enhances stability.

Motor layout: The walking motor is integrated with the drive axle to reduce transmission losses and improve efficiency.

2. Modular design

Power system: The battery pack, motor, and controller can be quickly disassembled for easy maintenance or replacement.

Hydraulic system: Pumps, valves, and oil tanks are integrated into the hydraulic station to reduce pipeline complexity and minimize leakage risks.

3. Compact design

Door frame structure: Made of high-strength thin-walled steel, reducing weight while maintaining rigidity.

Steering system: Electric power steering (EPS) replaces hydraulic power steering, saving space and reducing energy consumption.

The main equipment produced by Hebei Makita: stage electric hoist, electric chian hoist, wire rope electric hoist，Hand chain hoist, lever hoist, pneumatic hoist and other lifting equipment