Gears are devices that engage mechanical motion or transfer torque and motion through a shaft, other gears or a series of parts. Teeth cut evenly into the external circumference of gears are designed to fit with corresponding gears; when one gear turns, both gears' interlocking teeth cause the other gear to turn as well.
Gear shape and size determines gear performance. When interlocking gears differ in size from one another, the smaller gear will turn faster than the larger gear; the relationship between gear size and speed is called "speed ratio" or "gear ratio." A gear's number of teeth can be used to calculate a gear assembly's ratio. For example, if two interlocking gears have 40 teeth and 20 teeth respectively, the gear ratio is 2:1. Different sized gears are used with one another to increase or reduce a shaft's rotational speed in speed reducers, motors, transmissions, heavy machinery and clocks. Bevel gears, sprockets, rack and pinion spur gears, planetary gears, spline gears and helical gears are crucial in automotive motors and power transmissions, as are rear end gears and differential gears. Gear manufacturers produce a wide variety of gear configurations. Gear applications are variable and highly customizable, as different gear types can be configured in a virtually limitless number of ways to increase speed, reduce speed, transmit power, transmit motion or reduce the amount of force necessary to accomplish a task. From 20 foot diameter industrial gears to small worm gears and plastic gears, gear manufacturers make custom gear assemblies for nearly any application.
The simplest type of gear is the spur gear, or the "straight-cut gear." Spur gears are straight-sided along the gear wheel's axis with straight teeth radiating in alignment with the axis. Spur gears are often used as sprockets, which are thin gears with teeth that lock easily into roller chains. Sprockets act as a non-slip pulley for power transmission applications such as bicycle gears. Splines are cylinders or rods with straight teeth used to fit inside internal gears or devices to transmit motion laterally. Other types of spur gears fit with other parallel aligned gears, transmitting torque and motion laterally; these gears are a main component of planetary gears, or epicyclic gear trains. Planetary gears contain one central spur gear, or "sun gear" surrounded by three or more "planet gears;" the exterior gears interlock with the inward-facing teeth of a larger internal gear, increasing the output speed of the large outer gear through rotational torque applied to the internal sun gear. While spur gears are used in a wide range of simple and complex applications, planetary gears are used in complex automotive transmissions, drivetrains and other applications where complex gear ratios are required for smooth torque transmission.
Not all gears have straight, axis-aligned teeth. Worm gears' teeth are arranged around a cylinder-shaped gear like a screw; spur or helical gears interlock with the screw-like worm gear so that the axes are perpendicular. The worm usually drives the gear, providing a high level of speed reduction for applications such as textile looms, packaging machinery, material handling and conveyor systems. Helical gears are refined spur gears with helically angled teeth; these angled teeth engage more fully than straight-toothed spur gears as well as providing far smoother, quieter functioning. Helical gears can also be aligned parallel or crossed, allowing gears to transmit torque perpendicularly for a broader number of applications. Conically shaped bevel gears allow gears to interlock at perpendicular angles for applications such as rear end wheel torque in cars. Bevel gears may have straight teeth, or they may be spiral bevel gears with curved teeth, similar to helical gears. Bevel gears are used as rear end gears in cars, trucks, other self-powered vehicles and industrial machinery requiring perpendicularly transmitted torque. Automotive differential gears are bevel gears arranged into epicyclic configurations, which allow various attached axles to turn at different speeds.
Gear manufacturers use gear cutting techniques such as gear hobbing to fabricate gears, designing their products to withstand harsh and repetitive use. A gear's number of teeth and its specific gear ratio determine the function, speed and control the gear will have within a larger gear assembly. These factors will determine the gear's durability and strength and also the speed it will be able to engage. Gears may be made from a variety of materials, including most metals and hard plastics. Highly wear-resistant plastics such as nylon and polycarbonate are useful in machinery applications where low weight is a requirement. In demanding applications such as automotive transmissions, gears are made from hard metals such as steel, brass, copper and even titanium. Heat, vibration and the presence of corrosive elements are all possible impediments to gear performance, which is why most gear systems use a form of lubrication. Operations that involve the use of gears are much more likely to be successful if gear composition and configuration are chosen with careful consideration for properties of strength, heat and corrosion resistance. Gears that are properly matched to their applications can be expected to perform reliably much longer than improperly applied gear equipment.
Photo Courtesy of Commercial Gear and Sprocket Company, Inc.
Photo Courtesy of Omni Gear Machine Corporation
Gears are an essential part of the machines that many industries use. In the simplest definition, gears are wheels that have cut teeth and cogs that rotate and mesh with the teeth or cogs of another gear. Sometimes, there can be more than two gears in the mechanism. During the meshing of the teeth, the desired torque or speed is achieved, which is necessary for the smooth operation of the machine. These teethed wheels rotate with the power of an engine, which is chosen according to the requirements of the plants.
There are various types of industrial gears for different applications and requirements. We talk about some of the most used industrial gears in the following sections -
Spur Gear - The gears that have parallel shafts connected with the wheel are known as spur gears. The system of shafts connecting the wheels is called a spur gearing system, which is the most commonly used gearing system. These systems have straight teeth that are positioned parallel to the axis of the gear. The biggest benefit of spur gears is that they are very basic in design. Spur gear can work in traditional as well as contemporary machines. They also help manufacturers keep their production cost down. Although they are known for their slow speed, spur gears can be programmed to achieve any speed.
Helical Gear - The teeth of these gears are inclined toward the axis of the shaft and positioned like a helix, which is how helical gears get their name. These fast rotating gears can endure heavy loads smoothly and efficiently. When it comes to noise comparison, these gears are quieter than spur gears and many other types of gearwheels. Besides, these parts can bear both radial loads and thrust loads, making these an ideal utility for the businesses that have both applications in their process.
Bevel Gear - Gears with intersecting shafts that are located on the same plane are labelled as bevel gears. The arrangement of intersecting and coplanar or coexisting shafts is called a bevel gearing system. Straight and angled bevel gears are used for a large number of applications. However, the thickness and height of the tooth and the shaft should be chosen carefully according the type of application.
Miter Gear - Miter gears are a subcategory of bevel gears in which two rotational axes intersect each other at a programmed speed.
Spiral Bevel Gear - Spiral bevel gears have oblique teeth to meet special purposes. In comparison to straight gears, the spiral ones can take up more loads.
Zerol Bevel Gear - These are very similar to the straight bevel gears. However, they have teeth that are curved in length, but not angled. Zerol bevel gears can be described as an intermediate type between spiral and straight bevel gears.
Internal Gear - Internal gear is the gear that has teeth on the inner surface of a wheel, cylinder, or cone. These are used for specific applications, and are often designed specifically for the application.
External Gear - Similarly, there are external gears as well. These gears have teeth on the outer surface of the wheel or the cylinder.
Industrial gears are an elementary machine for industrial machines. These wheel-shaped machine parts play a key role in the smooth and unbarred functioning of the production process. Gears help control the power or movement of the machine's engine. The industrial gears of today are more useful and versatile than the ones of previous generations. Modern gears are used for a large number of applications, such as aviation, automotive, food production, railway, transportation, and the list goes on. For each sector and process, different kinds of gears are used, and perform different tasks. The following passages explain the operation of some of the most used industrial gears -
Bevel Gears: There are various subcategories of bevel gears, depending on the angle and position of the shaft and the teeth. Bevel gears are used for the operation needed to change the rotation of a shaft. With these gears, you can control the speed of the shaft, therefore the speed of the shaft's cycle. The shafts in bevel gears are positioned at 90 degree angle, however, they can be designed and programmed to work at different angles.
Girth Gears: Although different in design than other types of gears, Girth gears can still be used for a large number of applications. These gears are designed to have numerous segments. Sometimes, there could be just two segments, and for some purposes, there could be four or eight segments. The cost of designing and installing girth gears is quite low. Additionally, easy installation process and easy to understand functions make this gear a favorite utility of many manufacturing businesses.
Helical Gears: Helical gears could be considered the most popular type of gears that industrial machineries use. The teeth of these gears mesh with each others at a certain angle. The angle of meshing and rotation can be set according to the thrust load requirement of the application. The teeth and shaft in the system are located in helix like position, which is how these gears get their name helical. The helix locus of the shaft ensures smoother operation, apart from balancing the load more efficiently.
Differential Gears: These gears are mostly used in the design of automobiles. The gear has two shafts, and the direction and angle of both the shafts can be adjusted as desired. Differential gears are designed to mesh with each other at a controlled speed to produce the preferred amount of torque. In vehicles there is a series of coaxial gears that work together to enable the motor to achieve flawless operation.
Spur Gears: These are the most simple gears used in various industrial applications. However, they are used for a number of non-industrial operations as well. These are designed with a cylinder-like and disc-like shape to help the application achieve the desired speed and torque. These gears have straight and parallel teeth.
Gears are an important part of industrial machines. These teethed wheels regulate the speed of the machine and provide the machine with sufficient power to carry out its operations. There are various types of industrial gears, such as differential gears, worm gears, exterior or rear end gears - all of which have varied designs and working principles.
Be it whichever type of gears you are using in your application, they should be properly maintained in order to enhance their performance and endurance. The following descriptions underline a few tips that you can line up for the upkeep of your mechanical gears -
Check the rating of the gearbox
Every gearbox comes with labels and packaging. You should check the ratings given to the gear and the gearbox before initiating the machine. Keeping the rating of the gearbox in mind will help you determine how you have to use this set of gears. You need to make sure that you are using the gears as suggested by the manufacturer on the label or packaging.
Make provisions for dust and pollution management
Production facilities are high traffic and pollution zones. Additionally, many industrial procedures release fluids and particles that can build up on the parts of your machines, including their gears. Gears layered with dust particles have a direct impact on the performance of the machine. Therefore, you should make use of modern technology to remove dusts and pollutants from the edges and depths of your machines and their gears. Installing air ventilation systems, air curtains, vacuum cleaners and dust management system in place can help you in managing the pollution on your site.
Keep the water, fluids, and dust away from the gears and gearbox
Factors like water, moisture, chemicals, dust and dirt are a major threat to your gears. You should make adequate arrangements to keep such elements away.
Check the seals of the shaft
There should be no spillage on the shaft and the gear because of the broken seal. It is always better to give the gears a look, before starting the machine. This particular exercise can help you avoid expensive fuel bills caused by the overworking of your machines. Leaks can add potential factors that can hamper the output of the overall process. To avoid such hindrances, you should ask your engineers to put this exercise in their schedule.
If there's one thing that should be on gears, it is a lubricant. However, not every lubrication can be used for every gear. Read through the suggestions of the gear manufacturer prior to using anything to speed up the swirl of your gearwheels.
Never allow overheating
Overheating of the engine is another probable peril for your gears. Overheating can be a reason of overloading, inadequate process, and pollutants on the teeth or shaft of the gear. You should have your engineers ready to check for the possible reasons of overheating. There are many technologies, such as infrared ray emitting guns, that you can consider using to accomplish this specific job.
The distance the width of a tooth space surpasses the thickness of the
engaging tooth on the pitch circles of industry gears.
- The diameter of the hole in an industry gear.
- The larger gear of a set of industry gears.
- The smallest distance between the axes of non-intersecting, mating industry gears.
- Used for connecting two non-continuous shaft ends of industry gears.
- The distance, radial or perpendicular, between the bottom of the gullet and the pitch circle on industry gears.
- The distance between the teeth of industry gears.
- A cutting tool used for cutting teeth in industry gears by using a hobbing machine.
- An extension projecting from the side of industry gears that creates width to a part so it can be mounted on a shaft.
- The type of style of the hubs on industry gears. Type 'A' indicates there is no hub on the industry gear; type 'B' indicates there is a hub on only one side of the industry gear; type 'C' indicates there is a hub on both sides of the industry gear.
- The pitch diameter's ratio to the number of teeth on the industry gear expressed in millimeters.
- The distance from the crossing point of the axes to the location surface of industry gears.
- The smaller industry gear of a set of industry gears.
- The size of the teeth of industry gears.
- A steel bar with teeth on one side where a pinion can be driven across. Also a
spur gear with an unlimited pitch diameter.
- The distance from the center of industry gears to the point where the teeth or edges come into contact with one other. It is directly related to the size of one industry gear compared to the other.
- Edges or outside of industry gears have pits and extrusions to interlock with other industry gear parts. The teeth of the industry gears prevent slippage between the gears and promote consistency and regularity in the industry gears.