planetary gear reduction

Many “gears” are utilized for automobiles, however they are also used for many various other machines. The most typical one is the “transmitting” that conveys the energy of engine to tires. There are broadly two roles the transmission of a car plays : one can be to decelerate the high rotation speed emitted by the engine to transmit to tires; the other is to improve the reduction ratio relative to the acceleration / deceleration or traveling speed of an automobile.
The rotation speed of an automobile’s engine in the overall state of traveling amounts to at least one 1,000 – 4,000 rotations each and every minute (17 – 67 per second). Since it is unattainable to rotate tires with the same rotation acceleration to perform, it is necessary to lessen the rotation speed using the ratio of the amount of gear teeth. Such a role is called deceleration; the ratio of the rotation rate of engine and that of wheels is called the reduction ratio.
Then, why is it necessary to modify the reduction ratio relative to the acceleration / deceleration or driving speed ? The reason being substances require a large force to start moving however they do not require this kind of a sizable force to excersice once they have started to move. Automobile could be cited as an example. An engine, however, by its character can’t so finely modify its output. Consequently, one adjusts its result by changing the reduction ratio utilizing a transmission.
The transmission of motive power through gears very much resembles the principle of leverage (a lever). The ratio of the number of the teeth of gears meshing with one another can be considered as the ratio of the space of levers’ arms. planetary gear reduction That’s, if the decrease ratio is large and the rotation speed as output is low in comparison to that as insight, the energy output by tranny (torque) will be large; if the rotation speed as output is not so low in comparison compared to that as input, on the other hand, the energy output by transmitting (torque) will be small. Thus, to improve the decrease ratio utilizing transmission is much comparable to the theory of moving things.
Then, 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 mechanism consisting of 4 components, namely, sun gear A, several planet gears B, internal equipment C and carrier D that connects planet gears as observed in the graph below. It includes a very complex structure rendering its style or production most difficult; it can realize the high decrease ratio through gears, however, it really is a mechanism suited to a reduction mechanism that requires both little size and powerful such as transmission for automobiles.
In a planetary gearbox, many teeth are involved at once, that allows high speed decrease to be performed with relatively small gears and lower inertia reflected back to the engine. Having multiple teeth discuss the load also enables planetary gears to transmit high degrees of torque. The combination of compact size, large speed decrease and high torque transmission makes planetary gearboxes a popular choice for space-constrained applications.
But planetary gearboxes do have some disadvantages. Their complexity in style and manufacturing tends to make them a far more expensive solution than various other gearbox types. And precision production is extremely important for these gearboxes. If one planetary gear is put closer to the sun gear than the others, imbalances in the planetary gears may appear, resulting in premature wear and failure. Also, the small footprint of planetary gears makes heat dissipation more difficult, so applications that operate at high speed or encounter continuous operation may require cooling.
When utilizing a “standard” (i.e. inline) planetary gearbox, the motor and the powered equipment must be inline with one another, although manufacturers offer right-angle designs that include other gear sets (often 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 would depend on the drive configuration.
2 Max input speed linked to ratio and max result speed
3 Max radial load positioned at optimum load position
4 Weight varies with configuration and ratio selected
5 Requires tapered roller planet bearings (unavailable 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 motor input SAE C or D hydraulic
Precision Planetary Reducers
This standard selection of Precision Planetary Reducers are ideal for use in applications that demand powerful, precise positioning and repeatability. These were specifically developed for use with state-of-the-art servo motor technology, providing restricted integration of the electric motor to the unit. Style features include installation any servo motors, standard low backlash, high torsional stiffness, 95 to 97% efficiency and silent running.
They can be purchased in nine sizes with decrease ratios from 3:1 to 600:1 and result torque capacities up to 16,227 lb.ft. The output could be provided with a solid 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 amounts right down to 1 arc-minute are available. Right-angle and input shaft versions of the reducers are also obtainable.
Normal applications for these reducers include precision rotary axis drives, traveling gantries & columns, material handling axis drives and digital line shafting. Industries served include Material Handling, Automation, Aerospace, Machine Tool and Robotics.
Unit Design &
Construction
Gearing: Featuring case-hardened & surface gearing with minimal put on, low backlash and low noise, making them the many accurate and efficient planetaries obtainable. Standard planetary design has three world gears, with an increased torque edition using four planets also obtainable, please see the Reducers with Output Flange chart on the machine Ratings tab under the “+” unit sizes.
Bearings: Optional output bearing configurations for app specific radial load, axial load and tilting minute reinforcement. Oversized tapered roller bearings are standard for the ISO Flanged Reducers.
Housing: Single piece metal housing with integral band gear provides higher concentricity and get rid of speed fluctuations. The housing can be installed with a ventilation module to improve input speeds and lower operational temperature ranges.
Output: Available in a solid shaft with optional keyway or an ISO 9409-1 flanged interface. We offer a wide range of standard pinions to attach right to the output style of your choice.
Unit Selection
These reducers are typically selected based on the peak cycle forces, which often happen during accelerations and decelerations. These cycle forces rely on the driven load, the quickness vs. period profile for the cycle, and any other exterior forces acting on the axis.
For application & selection assistance, please call, fax or email us. The application details will be examined by our engineers, who’ll recommend the very best solution for the application.
Ever-Power Automation’s Gearbox product lines offer high precision in affordable prices! The Planetary Gearbox product offering contains both In-Line and Right-Angle 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, well suited for motors ranging from NEMA 17 to NEMA 42 and bigger. The Spur Gearbox collection offers an efficient, cost-effective choice appropriate for Ever-Power Automation’s AC Induction Gear Motors. Ever-Power Automation’s Gearboxes are offered in up to 30 different equipment ratios, with torque rankings up to 10,488 in-lbs (167,808 oz-in), and are appropriate for 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 available for the price point.
Features
Wide variety of ratios (5, 10, 25, 50, and 100:1)
Low backlash of 30 arc-min or less
20,000 hour service life
Free of maintenance; requires no additional lubrication
NEMA sizes 17, 23, and 34
Includes hardware for mounting 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 certainly are a type of cylindrical gear, with shafts that are parallel and coplanar, and the teeth that are directly and oriented parallel to the shafts. They’re arguably the easiest and most common type of gear – easy to manufacture and suitable for a range of applications.
One’s tooth of a spur gear have got an involute profile and mesh 1 tooth simultaneously. The involute type means that spur gears simply generate radial forces (no axial forces), however the approach to tooth meshing causes ruthless on the gear one’s teeth and high sound creation. For this reason, spur gears are often utilized for lower swiftness applications, although they can be utilized at almost every speed.
An involute tools tooth includes a profile this is actually the involute of a circle, which implies that since two gears mesh, they get in touch with at an individual point where in fact the involutes satisfy. This aspect actions along the tooth areas as the gears rotate, and the kind of force ( known as the line of activities ) can be tangent to both base circles. Hence, the gears stick to the fundamental regulation of gearing, which statements 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 for example metal or brass, or from plastics such as for example nylon or polycarbonate. Gears manufactured from plastic produce much less sound, but at the trouble of power and loading capability. Unlike other apparatus types, spur gears don’t encounter high losses because of slippage, therefore they often times have high transmission performance. Multiple spur gears can be employed in series ( referred to as a gear 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 opposite directions. Internal gears, in contrast, have tooth that are cut on the inside surface area of the cylinder. An external gear sits in the internal equipment, and the gears rotate in the same direction. Because the shafts sit closer together, internal gear assemblies are more compact than external equipment assemblies. Internal gears are primarily used for planetary equipment drives.
Spur gears are generally seen as best for applications that want speed decrease and torque multiplication, such as ball mills and crushing equipment. Types of high- velocity applications that make use of spur gears – despite their high noise amounts – include consumer appliances such as washing machines and blenders. And while noise limits the use of spur gears in passenger automobiles, they are generally found in aircraft engines, trains, and even bicycles.