planetary gears also refer as epicyclic gearing consisting three elements sun gear, planet equipment and ring gear. Sun gear is located at the guts that transmits torque to planet gears orbiting around sunlight gear. Both systems are located inside the ring gear. In the toothed formation sun and planet gears are externally mesh and band gear internally meshes.
Planetary gear is found in many variation and arrangements to meet up a broad selection of speed-ratio in the deign requirements. Planetary gear system is use in varies applications such as for example, clocks, lunar calendar, car mirror, toys, gearhead electric motor, turbine engine and more.
For detail understanding on the planetary
Planetary gear system will no assemble unless the number of teeth in each gear is selected properly.
Planetary spur gear drive ratio 5:1 means the sun gear must make 5 revolutions for every revolution of the output carrier.
Desired number of teeth in the sun gear is 24.
Design requirements:
Ratio = 5:1
Sun gear = 24
Module = 1
Since, I am working in the metric unit every dimension will be in mm. Selecting gears in metric device the gear 
tooth profile of the spur equipment will maintain Module.
M = Module
N = Number of teeth
Nr = Quantity of teeth on the ring gear
Pd= Pitch Diameter
R = Ratio
PDs=N/M=24/1=24mm Eq. 01
Pitch diameter of sunlight gear is 24.
Calculate the number if teeth required in the ring gear for the ratio 5:1.
R=1+Nr/Pd Eq. 02
Solve for Nr
Nr=Pd (R-1)=24(5-1)=24(4)=96 teeth
Pitch diameter of the band gear with 96 teeth and 1 module is.
Pd=Nr/M Eq. 03 Pd=96/1=96mm
Pitch diameter of the planet gears must be found from.
PDp=(Nr-PDs)/2=(96-24)/2=72/2=36mm
Number of teeth in this world gears may now end up being found from.
PDp=N/M Eq. 04 36mm=N/1 è 36mm (1)=N è N =36 teeth
Check:
R=1+Nr/P_D =1+96/24=1+4=5
The ratio is 5:1, as design was required.
Benefits of using planetary equipment motors in work
There are several types of geared motors that can be utilized in search for the perfect movement within an engineering project. Taking into account the technical specifications, the required performance or space limitations of our design, you should consider to make use of one or the various other. In this post we will delve on the planetary equipment motors or epicyclical gear, and that means you will know thoroughly what its advantages are and find out some successful applications.
The planetary gear systems are seen as a having gears whose disposition is very different from other models like the uncrowned end, cyclical (step-by-step) or spur and helical gears. How could we classify their elements?
Sun: The central equipment. It has a bigger size and rotates on the central axis.
The planet carrier: Its objective is to hold up to 3 gears of the same size, which mesh with the sun gear.
Crown or band: an outer band (with teeth upon its inner part) meshes with the satellites possesses the whole epicyclical train. In addition, the core can also become a middle of rotation for the outer ring, allowing it to easily change directions.
For accuracy and reliability, many automatic transmissions currently use planetary equipment motors. If we discuss sectors this reducer offers great versatility and can be utilized in very different applications. Its cylindrical shape is quickly adaptable to thousands of spaces, ensuring a sizable reduction in an extremely contained space.
Regularly this type of drives can be utilized in applications that want higher degrees of precision. For instance: Industrial automation machines, vending machines or robotics.
What are the primary advantages of planetary gear motors?
Increased repeatability: Its greater speed radial and axial load offers reliability and robustness, minimizing the misalignment of the apparatus. In addition, uniform transmission and low vibrations at different loads give a perfect repeatability.
Perfect precision: Most rotating angular stability enhances the accuracy and reliability of the motion.
Lower noise level since there is more surface area contact. Rolling is much softer and jumps are practically nonexistent.
Greater durability: Because of its torsional rigidity and better rolling. To improve this feature, your bearings lessen the losses that would occur by rubbing the shaft on the box directly. Thus, greater effectiveness of the gear and a much smoother procedure is achieved.
Very good levels of efficiency: Planetary reducers offer greater efficiency and thanks to its design and internal layout losses are minimized throughout their work. In fact, today, this kind of drive mechanisms are those that offer greater efficiency.
Improved torque transmission: With more teeth in contact, the mechanism will be able to transmit and withstand more torque. Furthermore, it can it in a far more uniform manner.
Maximum versatility: The mechanism is within a cylindrical gearbox, which may be installed in nearly every space.
The construction of the planetary reducer lends itself to numerous advantages, for example:
Planetary reducers give you high torque in a compact package; sharing the strain between several world gears allows the reducer to take care of the same torque that bigger parallel axis gear sets handle.
They are highly efficient with an individual stage typically 95% efficient.
These reducers provide for ratios as high as 11:1 to be achieved within a stage, whereas, it really is difficult to achieve higher than 5:1 within a parallel axis stage.
Since the sun gear contacts multiple planet gears, level of resistance to elastic deformation, is higher in a planetary gear set than parallel axis gear set, giving the planetary reducer high torsional stiffness.
They enable coaxial alignment, meaning no offset result shaft in relation to the motor shaft.
The output shaft upon Planetary reducers rotates in the same direction because the engine without needing an idler equipment, because in a parallel axis equipment set.
Planetary reducers are perfect for intermittent duty applications but also can be utilized in continuous duty applications.
Finally, Ever-Power planetary’s possess a built-in housing, meaning the ring gear is built-into the outer housing for the gearbox, adding to the robusticity.
Compared to the benefits of the planetary reducers, the drawbacks are minimal for most applications for example:
High ratio of length to diameter when using multiple stages (gearhead can get very long).
Possibly high cost if low backlash, high precision gearing is required.
Specific numbers of gear teeth are required equally spaced planets (ease of assembly) and noise mitigation.
The apparatus ratio determines just how many planet gears may be used.
You should consider planetary reducers when making for applications requiring high torques in a small package with an output shaft must be co-axially aligned with the engine.
Product Overview
Product Usage:
All Ever-Power gearboxes require grease for proper procedure and long life. We suggest using our red tacky grease, am-2768. We also encourage that an individual powers the gearbox consistently for thirty minutes without grease to permit the apparatus teeth to use in. While we do design with short run occasions in mind, this ‘run in’ period for smooth gearbox procedure, is recommended. Once that is completed, comprehensive grease of the gear teeth periodically to ensure smooth operation.
Single speed planetary gearbox, with the same mounting and output interface as a 2.5″ CIM motor. Each planet gear has its own bearing to spin freely on the carrier plate pins. A 2.5″ CIM Motor may also be used as the motor input, but requires this pinion equipment ( am-0556) and a CIM Spacer (am-0555).
Motor Input:
9015 motor fits on this gearbox
550 motor fits upon this gearbox
2.5″ CIM Motor could be mounted, with a bored-out sun gear and a spacer
Included Hardware:
Two – 8mm id ball bearings, (19mm od, 22mm od) supporting output shaft
One – Steel world and sun gears, 32 dp, 20 degree p.a.
Five – Planet gears (12 tooth)
One – 15 tooth sunlight gear, with 0.125 inch bore
One – 40 tooth band gear
Performance Data:
(with the insight being a 9015 motor)
Input voltage: 12 volts
Stall Torque: 1.12 ft-lb.
Free speed: approximately 4,000 rpm
Assembly Tip:
Install the light weight aluminum plate to the face of the motor BEFORE pressing the pinion gear onto the motor shaft.
Specifications
Material: body is definitely aluminum, shaft is 4140 steel
Mounting Holes: #10-32 tapped holes (2), on a 2″ bolt circle to attach at output shaft
Outdoors dimension: 2.5 in.
Ratio: 3.67:1
Shaft Diameter: 0.313 inch,with 2mm keyway
Weight: 0.63 lbs
PLANETARY GEAR SYSTEM
A planetary transmission system (or Epicyclic system since it is also known), consists normally of a centrally pivoted sun gear, a ring gear and several planet gears which rotate between these.
This assembly concept explains the word planetary transmission, as the planet gears rotate around the sun gear as in the astronomical sense the planets rotate around our sun.
The benefit of a planetary transmission depends upon load distribution over multiple planet gears. It is thereby possible to transfer high torques employing a compact design.
Gear assembly 1 and equipment assembly 2 of the Ever-Power 500/14 possess two selectable sun gears. The first gear step of the stepped planet gears engages with sun gear #1. The second gear step engages with sun gear #2. With sunlight gear 1 or 2 2 coupled to the axle,or the coupling of sun gear 1 with the ring gear, three ratio variations are achievable with each gear assembly.
The decision between helical and spur gears in gearboxes may seem straightforward. Move with helical gears if you would like the gearbox to run as smoothly and quietly as feasible. Choose spur gears when you need to maximize the gearbox’s torque density or operating existence under higher loads.
These rules of thumb are mostly what you need to know when specifying traditional fixed-axis gearboxes. Just size the gearbox correctly, and the decision between helical and spur gears may also be obvious for confirmed set of app requirements. With planetary gearboxes, however, the choice between helical and spur gears requires some extra thought.
Helical Gears Create Axial Forces
As you might expect from their different mesh geometries, spur and helical gears have completely different loading characteristics. With their zero helix angle, spur gears lack an axial load component. And they suffer from hardly any sliding tooth contact.
Helical gears, in comparison, generate significant axial forces in the apparatus mesh. In addition they exhibit more sliding at the idea of tooth contact, adding friction forces into the mix.
Helix angles in gearboxes usually fall in a range of 15 to 30 degrees. As the position increases, both axial forces and sliding get in touch with increase.
The main reason for using helical gears is the increased number of teeth connected at any moment, which really is a fundamental requirement of smooth torque transmission. With their
increased contact ratio compared to spur gears, helical gears have a lower fluctuation
of the gear mesh stiffness.
Helical Gears Place Higher Demand on Bearings
Since they won’t need to withstand any axial forces, spur gear bearings perform just a supporting part in the functioning of the gearbox. The bearings should just support the rotating gear shafts, but they do not play an active function in torque transfer.
The presence of axial forces makes things very different for the bearings that support helical gears. But it is critical to make a distinction between fixed-axis and planetary gearboxes. In fixed-axis gearboxes, the excess axial forces total little more than an inconvenience. Gearbox designers will most likely upsize the bearings to accommodate the additional forces.
Or, in extreme cases, they could select angular get in touch with or tapered roller bearings, both of which are created to withstand axial loads.
Space restrictions within planetary gearboxes mean that the earth gear bearings should be chosen more for his or her size than their tolerance for high axial loads.
In planetary gearboxes, however, it’s a lot more difficult to design around these axial forces for two related reasons. 1st, there is typically very little room in a planetary gearbox to include the kind of bulky bearings that may tolerate high axial forces.
Second, the planet gear bearings need to play an active function in torque transfer. Planetary systems split the torque insight from sunlight gear amongst the planet gears, which transfer torque to a world carrier connected to the gearbox result. The bearings that support the planets on the carrier have to bear the full brunt of that torque transfer.
And Here Is the Difficulty
The limited space within planetary gearboxes means that the bearings used for the earth gears must be chosen more for their size than their tolerance for high axial loads. In general, small needle roller bearings are the most common choice in these configurations.
Needle roller bearings do a good work with radial loads that are evenly distributed along the length of the needle. But they don’t handle axial loads well.
In planetary systems, the direction of the axial force in the sun-planet mesh opposes that of the force in the planet-ring gear mesh. Therefore the world sees significant tilting minute described by the axial drive times equipment pitch diameter. This tilting second produces an uneven load distribution along the needle rollers, drastically decreasing the bearings’ load transporting capability and lifecycle.
Loads on the roller bearings will change, depending on their placement around the shaft. Minute is approximately the Z-axis, and models are in ins and pounds.
The Planetary Motion Is The Principle For The Planetary Gearbox.
The Accurately Positioned And Meshed World Gears (3) With SUNLIGHT Gear In The Centre And THE INNER Teeth Of The Outer Band Gear Compose Each Stage Of A Planetary Gearbox.
The Sun Gear Gets The Input While The 3 Planet Gears SUPPLY THE Ouput WITH A Planet Carrier .
The Torque Handling Capability Is Very High DUE TO ITS Flexibility , And AN EXTREMELY High Weight /Volume Ratio , Thus It Lends Its Software In Various Industries – Specifically In High Torque Requirements RENDERING IT The Most Economical Remedy.
Being A Proud Provider Of Planetary Gearbox, WE OFFER A FANTASTIC Distinguished Service To Our Clientile.
Planetary Gearbox Product Specs :
Provides High Torque In Slow Speeds.
Our SELECTION OF Gearboxes And Geared Motors Are Manufactured As Per The American Gear Manufacturers Association (AGMA) Standards.
The Shafts ARE MADE Of Hardened And Tempered Particular Alloy Steel.
Sun And Planet Gears Are Made Of Case Carburised And Ground Alloy Steel.
Ring Gears Are Made Up Of Forged Alloy Metal.
Best Load Sharing Because Of Accurate Positioning Of Planets.
Low Noise Levels.
No Oil Leakage.
Good Quality Taper Roller Bearings For Input And Output Shafts.
Very High Efficiency
