1. Overview

The selection of mechanical transmission should be combined with technical performance and economy, and comprehensively weigh the requirements of working conditions, efficiency objectives, space constraints, environmental adaptability and cost control.

High precision scenario: priority gear transmission or ball screw transmission

Long distance transmission: priority belt or chain transmission

Stepless transmission requirements: friction wheel transmission

Belt drive

The friction between the elastic band and the pulley is used to transmit power, which is suitable for the scene with large center distance between two shafts.

merit:

Suitable for long distance transmission (large center distance), strong buffer vibration absorption, can absorb impact and vibration;

Slip in overload can protect the equipment and avoid damage to other parts;

Simple structure, low cost, no lubrication.

shortcoming:

The outer dimension is large, and additional tensioning device is required;

The transmission ratio is not accurate and the efficiency is low;

It is susceptible to temperature and humidity, and has a limited life.

Applicable occasions: light load, medium load transmission, such as home appliances, conveyor belt, etc.

Gear transmission The power is directly transmitted through gear meshing, with accurate transmission ratio and wide application range.

merit:

High transmission efficiency (up to 98% or more), transmission ratio range is large;

Compact structure, strong bearing capacity, long life;

The instantaneous transmission ratio is constant and the stability is good.

shortcoming:

High manufacturing and installation accuracy requirements, high cost;

Not suitable for long distance transmission;

It needs regular lubrication and has large noise.

Applicable occasions: high precision, high power transmission, such as car gearbox, industrial machinery.

4. Chain drive

The power is transmitted through the meshing of chain and sprocket, which has the characteristics of belt drive and gear drive.

merit:

When the center distance is large, the structure is simpler, and the manufacturing and installation accuracy requirements are lower than gear transmission;

No elastic sliding, the average transmission ratio is accurate;

Strong carrying capacity, suitable for harsh environment.

shortcoming:

The instantaneous transmission ratio is not constant, and the transmission stability is poor;

Need lubrication and maintenance, easy to wear;

High speed noise is large.

Applicable occasions: medium and long distance transmission, such as bicycles, motorcycles, agricultural machinery.

5. Screw drive

The screw rod and nut are engaged to convert the rotary motion into linear motion.

merit:

Simple structure, can realize self-locking function;

Smooth transmission, high precision (such as ball screw);

Suitable for fine tuning or low speed heavy load scenarios.

shortcoming:

Low transmission efficiency (large friction loss);

It needs precision processing and the cost is high;

Speed is limited and not suitable for high speed transmission.

Applicable occasions: precision positioning (such as machine tool screw), lifting equipment, etc.

6. Friction wheel transmission

Power is transmitted through the contact surface between two friction wheels, and motion and torque are transmitted by relying on friction force. It is suitable for parallel shaft or intersecting shaft transmission.

merit:

Simple structure, low manufacturing and maintenance cost, suitable for the scene of two shafts with close center distance;

The transmission noise is small, the operation is stable, can realize stepless speed change or change the transmission direction in operation;

Overload protection function: when overloaded, the friction surface slips to avoid damage to other parts;

High transmission performance and long life.

shortcoming:

The transmission ratio is not constant, there is a sliding rate, the accuracy is low;

The axial pressure is large, which requires high strength bearing support, resulting in the increase of structural size;

Low efficiency, large friction loss, wear parts need to be replaced regularly;

Environmentally sensitive: humidity and temperature changes may affect the friction coefficient.

Suitable for: light load machinery (such as textile equipment), continuously variable transmission devices (such as the conical ring transmission in the patent), scenes that require overload protection