Spur Gear Description

From the perspective of power transmission characteristics, a spur gear is a type of gear that achieves linear power transmission

through ‘face contact’. Its teeth are uniformly distributed along the axial direction, with the tooth surface comprising a combination

of a flat plane and an involute curve.

Key Features

Its defining feature is that force transmission occurs perpendicular to the gear axis during operation,

with stable tooth contact areas free from helical component interference.

Key advantages include high transmission efficiency (typically 95%-98%), minimal torque loss,

suitability for applications demanding high power fidelity, and absence of additional resistance during reverse rotation.

Working Principle

When the driving gear rotates, its involute tooth surfaces engage with the driven gear's teeth via line contact.

The normal force between the tooth surfaces propels the driven gear's rotation, directly transmitting the driving shaft's torque

and rotational speed to the driven shaft. Radial forces predominate during transmission, while axial forces are negligible.

Applications

Commonly employed for direct power transmission between a source and an actuator, such as connecting small motors to fans,

auxiliary drive systems in diesel generators, and gear pump drive mechanisms in hydraulic power units.

Technical Specifications

Steel Code Grades Comparison