planetary gear reduction

Many “gears” are utilized for automobiles, but they are also utilized for many other machines. The most frequent one is the “transmitting” that conveys the energy of engine to tires. There are broadly two functions the transmission of a car plays : one is usually to decelerate the high rotation swiftness emitted by the engine to transmit to tires; the additional is to change the reduction ratio relative to the acceleration / deceleration or generating speed of an automobile.
The rotation speed of an automobile’s engine in the overall state of generating amounts to 1 1,000 – 4,000 rotations per minute (17 – 67 per second). Because it is unattainable to rotate tires with the same rotation acceleration to run, it is required to lower the rotation speed using the ratio of the amount of gear teeth. This kind of a role is named deceleration; the ratio of the rotation acceleration of engine and that of wheels is called the reduction ratio.
Then, exactly why is it necessary to alter the reduction ratio relative to the acceleration / deceleration or driving speed ? This is because substances need a large force to start moving however they usually do not require such a big force to keep moving once they have began to move. Automobile could be cited as an example. An engine, however, by its nature can’t so finely modify its output. For that reason, one adjusts its result by changing the reduction ratio employing a transmission.
The transmission of motive power through gears quite definitely resembles the principle of leverage (a lever). The ratio of the number of the teeth of gears meshing with one another can be deemed as the ratio of the distance of levers’ arms. That is, if the reduction ratio is large and the rotation velocity as output is lower in comparison compared to that as insight, the energy output by transmitting (torque) will be huge; if the rotation speed as output is not so low in comparison to that as insight, however, the energy output by tranny (torque) will be small. Thus, to change the reduction ratio utilizing transmission is much akin to the theory of moving things.
After that, how does a transmitting change the reduction ratio ? The answer is based on the system called a planetary gear mechanism.
A planetary gear system is a gear system consisting of 4 components, namely, sunlight gear A, several planet gears B, internal equipment C and carrier D that connects world gears as seen in the graph below. It includes a very complex structure rendering its design or production most difficult; it can understand the high decrease ratio through gears, however, it really is a mechanism suitable for a reduction mechanism that requires both little size and high performance such as transmission for automobiles.
In a planetary gearbox, many teeth are involved at once, which allows high speed decrease to be achieved with relatively small gears and lower inertia reflected back again to the engine. Having multiple teeth share the load also enables planetary gears to transmit high degrees of torque. The mixture of compact size, huge speed reduction and high torque tranny makes planetary gearboxes a popular choice for space-constrained applications.
But planetary gearboxes do involve some disadvantages. Their complexity in style and manufacturing tends to make them a more expensive alternative than other gearbox types. And precision manufacturing is extremely important for these gearboxes. If one planetary gear is put closer to the sun gear compared to the others, imbalances in the planetary gears can occur, resulting in premature wear and failing. Also, the compact footprint of planetary gears makes warmth dissipation more difficult, therefore planetary gear reduction applications that run at very high speed or encounter continuous procedure may require cooling.
When using a “standard” (i.electronic. inline) planetary gearbox, the motor and the driven equipment must be inline with one another, although manufacturers provide right-angle designs that integrate other gear sets (frequently bevel gears with helical the teeth) to provide an offset between your input and output.
Input power (max)27 kW (36 hp)
Input speed (max)2800 rpm2
Output torque (intermittent)12,880 Nm(9,500 lb-ft)
Output torque (continuous)8,135 Nm (6,000 lb-ft)
1 Actual ratio is dependent on the drive configuration.
2 Max input speed linked to ratio and max output speed
3 Max radial load positioned at optimum load position
4 Weight varies with configuration and ratio selected
5 Requires tapered roller planet bearings (not available with all ratios)
Approximate dry weight100 -181 kg (220 – 400 lb)4
Radial load (max)14,287kg (31,500 lb)3
Drive typeSpeed reducer
Hydraulic electric motor input SAE C or D hydraulic
Precision Planetary Reducers
This standard range of Precision Planetary Reducers are ideal for use in applications that demand powerful, precise positioning and repeatability. These were specifically developed for make use of with state-of-the-art servo electric motor technology, providing tight integration of the engine to the unit. Style features include installation any servo motors, regular low backlash, high torsional stiffness, 95 to 97% efficiency and tranquil running.
They are available in nine sizes with reduction ratios from 3:1 to 600:1 and result torque capacities up to 16,227 lb.ft. The output could be provided with a good shaft or ISO 9409-1 flange, for installation to rotary or indexing tables, pinion gears, pulleys or other drive elements without the need for a coupling. For high precision applications, backlash levels right down to 1 arc-minute can be found. Right-angle and insight shaft versions of the reducers are also obtainable.
Common applications for these reducers include precision rotary axis drives, traveling gantries & columns, material handling axis drives and digital line shafting. Industries offered include Material Handling, Automation, Aerospace, Machine Tool and Robotics.
Unit Design &
Construction
Gearing: Featuring case-hardened & floor gearing with minimal use, low backlash and low sound, making them the the majority of accurate and efficient planetaries obtainable. Standard planetary style has three planet gears, with a higher torque version using four planets also obtainable, please see the Reducers with Result Flange chart on the machine Ratings tab under the “+” unit sizes.
Bearings: Optional result bearing configurations for app particular radial load, axial load and tilting second reinforcement. Oversized tapered roller bearings are standard for the ISO Flanged Reducers.
Housing: Single piece steel housing with integral band gear provides greater concentricity and eliminate speed fluctuations. The casing can be fitted with a ventilation module to improve input speeds and lower operational temps.
Result: Available in a good shaft with optional keyway or an ISO 9409-1 flanged interface. You can expect an array of standard pinions to install right to the output style of your choice.
Unit Selection
These reducers are usually selected based on the peak cycle forces, which usually happen during accelerations and decelerations. These cycle forces depend on the powered load, the swiftness vs. time profile for the cycle, and any other external forces functioning on the axis.
For application & selection assistance, please call, fax or email us. Your application details will be reviewed by our engineers, who’ll recommend the best solution for your application.
Ever-Power Automation’s Gearbox products offer high precision at affordable prices! The Planetary Gearbox item offering contains both In-Line and Right-Position configurations, built with the look goal of supplying a cost-effective gearbox, without sacrificing quality. These Planetary Gearboxes can be found in sizes from 40mm to 180mm, perfect for motors which range from NEMA 17 to NEMA 42 and larger. The Spur Gearbox range offers an efficient, cost-effective choice appropriate for Ever-Power Automation’s AC Induction Gear Motors. Ever-Power Automation’s Gearboxes can be found in up to 30 different equipment ratios, with torque ratings up to 10,488 in-pounds (167,808 oz-in), and are compatible with most Servo,
SureGear Planetary Gearboxes for Little Ever-Power Motors
The SureGear PGCN series is a good gearbox value for servo, stepper, and other motion control applications requiring a NEMA size input/output interface. It provides the best quality designed for the price point.
Features
Wide range of ratios (5, 10, 25, 50, and 100:1)
Low backlash of 30 arc-min or less
20,000 hour service life
Maintenance free; requires no additional lubrication
NEMA sizes 17, 23, and 34
Includes hardware for installation to SureStep stepper motors
Optional shaft bushings designed for mounting to other motors
1-year warranty
Applications
Material handling
Pick and place
Automation
Packaging
Additional motion control applications requiring a Ever-Power input/output
Spur gears are a type of cylindrical equipment, with shafts that are parallel and coplanar, and tooth that are directly and oriented parallel to the shafts. They’re arguably the easiest and most common kind of gear – simple to manufacture and ideal for a range of applications.
One’s teeth of a spur gear ‘ve got an involute profile and mesh one particular tooth simultaneously. The involute type implies that spur gears just generate radial forces (no axial forces), however the method of tooth meshing causes high pressure on the gear the teeth and high noise creation. Because of this, spur gears are often utilized for lower swiftness applications, although they can be utilized at nearly every speed.
An involute tools tooth carries a profile this is actually the involute of a circle, which implies that since two gears mesh, they speak to at a person point where in fact the involutes satisfy. This aspect motions along the tooth areas as the gears rotate, and the type of force ( known as the line of actions ) is tangent to both base circles. Hence, the gears adhere to the essential regulation of gearing, which promises that the ratio of the gears’ angular velocities must stay continuous through the entire mesh.
Spur gears could possibly be produced from metals such as metal or brass, or from plastics such as for example nylon or polycarbonate. Gears manufactured from plastic produce less audio, but at the difficulty of power and loading capability. Unlike other products types, spur gears don’t encounter high losses because of slippage, so they often have high transmission performance. Multiple spur gears can be utilized in series ( known as a equipment teach ) to achieve large reduction ratios.
There are two primary types of spur gears: external and internal. Exterior gears have one’s teeth that are cut externally surface of the cylinder. Two external gears mesh with one another and rotate in reverse directions. Internal gears, in contrast, have the teeth that are cut on the inside surface area of the cylinder. An exterior gear sits within the internal equipment, and the gears rotate in the same direction. Because the shafts are positioned closer together, internal gear assemblies are more compact than external equipment assemblies. Internal gears are primarily used for planetary equipment drives.
Spur gears are usually seen as best for applications that want speed reduction and torque multiplication, such as ball mills and crushing equipment. Examples of high- velocity applications that make use of spur gears – despite their high noise levels – include consumer appliances such as washers and blenders. Even though noise limits the usage of spur gears in passenger automobiles, they are generally found in aircraft engines, trains, and even bicycles.