Function of gear
Gears are commonly used to transfer rotational motion between mechanical shafts. When different types and sizes of gears are combined, the speed and direction of the rotation axis can be changed to turn the rotation motion into a straight line motion.
Functions and important parameters of gears
Since there are many different types of gears, our common gears have spur gears. Spur gear is mainly divided into external spur gear and internal spur gear two kinds, the external spur gear may be commonly used and relatively simple gear system, the external spur gear is the straight teeth parallel to the axis of the cylindrical gear. They are used to transmit rotational motion between parallel axes, which rotate in opposite directions. When two gear surfaces are in contact at the same time, they tend to produce noise at high speeds.
Internal spur gear: The internal spur gear works in a similar way to the external spur gear, except that the pinion is located inside the spur gear. They are used to transmit rotational motion between parallel axes, but in this arrangement the axes rotate in the same direction. The internal spur gear of the internal spur gear works in a similar way to the external spur gear, except that the pinion is the inside of the spur gear. They are used to transmit rotational motion between parallel axes, but in this arrangement the axes rotate in the same direction.
What are the important parameters of the gear
Several important parameters of the gear: modulus, indexing circle, pressure Angle and parameter parameters, etc. Module is a very important parameter in gear transmission. The size of the gear teeth is defined by the modulus. Modulus The symbol m (modulus) and the number (mm) indicate that the smaller the tooth size, the smaller the modulus, the larger the tooth size, the larger the modulus. Multiply the modulus by PI to get the pitch (p), which is the length between two adjacent teeth. Formula: p= PI x modulus = πm
Index circle: The index circle is a dimensional reference chosen for ease of gear design and manufacturing. There are standard modulus and standard pressure Angle on the gear index circle, which are generally used as the basis for calculation. The circumference of the gear index circle =Td=zp.
Pressure Angle: The pressure Angle is the Angle at which the tooth is tilted relative to the normal of the pitch line. The pressure Angle is generally 20°. However, pressure angles of 14.5° or 17.5° are sometimes used. The larger the pressure Angle, the wider the tooth root, the higher the strength. Angle between radius line and tangent line of tooth profile. The pressure Angle (α) is generally 20°. Modulus (m), pressure Angle (α) and number of teeth (z) are the three basic parameters of a gear.
Function and main parameters of gear
The number of teeth: the important parameters of the gear are the number of teeth, and the number of teeth of a pair of meshing gears needs to be determined to calculate the speed ratio. It is necessary to minimize the number of teeth of the pinion to expand the reduction or increase the ratio. However, the top of a rack tool may overlap with the root, and if the number of teeth falls below a specific value, the top may measure the root.
