A gearbox is often called a transmission. A gearbox simply refers to a set of gears and their casing, most commonly found in automobiles. Since most automotive engines have high operating and idle speeds, transmissions allow the machine to run efficiently and also help slow down and stop the machine.
Gearboxes are used to transfer energy from one rotational power source to another and are found in automobiles, turbines, and heavy machinery. In this article, you will learn about gearboxes and their types.
What is Gear Box?
A gearbox is a mechanical device that is used to increase the output torque or change the speed (RPM) of the motor. The motor shaft is connected to one end of the gearbox and through the internal configuration of the gears of the gearbox, it provides an output torque and a specific speed determined by the gear ratio.
The most basic definition of a gearbox is that it is a mechanical unit or component consisting of a gear train or set of gears embedded in a housing. In fact, the name itself defines it as a box containing gears. In the most basic sense, a gearbox works like a gear system. Change torque and speed between a drive, such as a motor, and a load.
Gears in gearboxes can be one of several types, from bevel and helical gears to worm gears and planetary gears. The gear is mounted on a shaft supported by roller bearings and rotates around it. A gearbox is a mechanical method of transferring energy from one device to another, which is used to increase torque while decreasing speed.
Gearboxes are used in many applications, including machine tools, industrial equipment, conveyor belts, and almost any power transmission application with rotary motion that requires a change in torque and speed.
how a gearbox works?
Conventional gearboxes usually have two sets of gears: input and output. the input & the output. The input gears are fixed on the countershaft, making them single units. It drives the individual gears on the main shaft, which rotate freely on the bearings.
So, the gearbox transmits power to the wheels depending on which gear is engaged on the main shaft. Additionally, pushing the shifter sleeve into the desired gear locks the gear to the main shaft and rotates it. Therefore, the main shaft rotates at the speed of meshed gears and provides power according to the ratio of meshed gears.
Gearbox: Speed vs. Traction
Basically, driving a car requires both speed and traction. Transmission gears help you choose one or the other depending on your driving situation.
The lower gears, 2nd and 1st, provide the best traction, while the higher gears, 5th and 6th (if available) provide the most acceleration. In addition, the number of gears in the gearbox provides an excellent combination of traction and speed.
So, it helps the driver/rider to choose the most suitable combination to increase efficiency. Therefore, it is very important to choose the right gear according to the road conditions and the load. Shorter gears improve acceleration and pickup, while higher gears improve top speed.
Types of Gearboxes
In general, there are three different types of gearboxes: concentric, parallel, and right angle. A fourth type called shaft mount is also used in situations where the applications are in a configuration where they cannot be mounted by foot.
| Type of Gearbox | Shaft Arrangement | Mounting |
| Concentric | High and low-speed shafts are on the same horizontal and vertical plane | Foot mounted |
| Parallel | High and low-speed shafts are on the same horizontal plane and parallel to each other | Foot mounted |
| Right Angle | High and low speed shaft have a 90-degree relationship | Foot mounted |
| Shaft Mount | The gearbox is mounted directly onto and supported by the driven shaft | Shaft mounted |
Below are some of the different types of industrial gearboxes and how they are used.
1. Helical Gearbox:
The helical gearbox consumes less power and is compact in size. This equipment is used in a wide variety of industrial applications, but is typically used for heavy duty applications. Worm gearboxes are popular in construction of plastic, cement, rubber and other heavy industrial environments. Crushers, extruders, chillers, conveyors, etc. are all useful for low consumption applications.
Helical gears are unique in that they are at a fixed angle that allows more teeth to interact in the same direction during operation. This creates a consistent point of contact for a period of time. Extruder helical gearboxes are used in extruders where maximum torsional stiffness is required and for low noise applications. Extrusion gearboxes are used in plastic industries and machines that require high mechanical strength.
2. Coaxial helical inline:
What makes it unique is that it is at a fixed angle which allows for more interaction in the same direction of movement. This results in constant contact for a certain period of time. Extruder helical gears are also used for optimum use of torsional strength and for mild applications. Applications include steel, rolling mills, conveyors, elevators, and the oil industry.
3. Bevel Helical Gearbox:
Do you know the key feature of this gearbox? It is a set of curved teeth on a conical surface near the edge of the machine. Bevel gears are also used to create rotary motion between non-parallel shafts. They are involved in mines, mixers and conveyor belts.
4. Worm Gearboxes:
The worm gearbox uses a large diameter warm wheel. A worm or screw meshes with teeth on the outer circumference of the gearbox. The rotation of the worm gear drives the wheel in the same way and in a screw-like motion. This setup is designed to allow the gear to turn, but the gear cannot turn the worm.
It is used for braking and emergency stops in conveyor systems due to the flat angle of the screw. These gearboxes are also used in pharmaceutical and packaging machines, conveyor belts in bottling factories and food industry machines.
5. Planetary Gearbox:
Planetary gearboxes are considered ideal and are also known for their durability, precision and unique performance. It is characterized has a detailed application. Planetary gears extend the life of your machine and maximize its performance.
This gearbox is available as a solid hollow or with different installation options such as flange, foot and shaft. The applications of this tool vary depending on the industry. However, the main point is that gearboxes are designed to simplify mechanical functions in various industries.
