A gear is a mechanical part with teeth on the rim that can continuously mesh and transmit movement and power. Each convex part of the gear used for meshing is called a gear tooth, which is generally called a tooth. These convex parts are generally arranged in a radial pattern. The gear teeth on the mating gear contact each other, which can make the gear continue to mesh. The total number of gear teeth on the entire circumference of the gear is called the number of teeth. The following is a brief analysis of the types of gears of robot parts, speed ratios, and the advantages and disadvantages of gear units from ALLOY WIKI.
The teeth that can mesh with each other must be the same size, so the number of teeth with a larger diameter in the meshing gears will be more, and the number of teeth with a smaller diameter will be less. However, the gears have the same number of teeth during rotation. A gear with a large diameter transmits one cycle, and a gear with a small diameter rotates several times. Therefore, a gear with a large diameter drives a gear with a small diameter, and the speed becomes faster. It is called an accelerating gear. Device.
Note: When parallel meshing, the direction of rotation of the gear is on the same plane, and the direction of rotation is opposite. When meshing vertically, the transmission direction of the gear is on two vertical planes, the direction of rotation is changed, and the direction of force is also changed.
Types of gears
There are many types of gears, which are generally divided into bevel gears, spur gears, crown gears and turbines according to their shapes. The frequently used gears are bevel gears and flat gears.
Turbines and worms are often used to transmit motion and power between two interleaved shafts. The unique feature is that the worm can easily turn the worm wheel, but the worm wheel cannot turn the worm. This is because the protrusion angle on the worm is very shallow. When the worm wheel tries to rotate the worm, the friction between the worm wheel and the worm will keep the worm in place.
Gear speed ratio
Calculate the gear speed ratio. It is known that the radius ratio of the first gear to the second gear is 3; 1, then the speed ratio of the first gear to the second gear is 1; 3, the speed ratio of the second gear to the third gear is 3; 1 , So the speed ratio of the first gear to the third gear is 1; 1. Summary: Calculating the output gear speed between the gears that meshed side by side once, can bypass all the transmission processes in the middle, and directly compare the radius ratio or gear ratio of the driving wheel and the output wheel.
Advantages and disadvantages of gear units
- 1. It can transmit power accurately. In gear transmission, the gear teeth mesh, the driving wheel rotates a gear tooth, and the driven wheel rotates a gear tooth accordingly. This transmission method ensures the accuracy of the movement.
- 2. The gear transmission force is large, and the gear transmission is through the meshing between the gear teeth, and the transmission force is greater than the belt and other devices.
- 3. The structure is compact and suitable for short-distance transmission. When it cannot be directly meshed, it can be driven by multiple gears.
- 1. The noise is large, and the gear transmission force is large, so the noise generated is relatively large
- 2. It is easy to be damaged. When changing speed, the gear teeth are easy to break due to the large transmission force.
- 3. Inadvertently pinch your fingers.