planetary gears also refer as epicyclic gearing consisting three components sun gear, planet gear and ring gear. Sun gear is situated at the center that transmits torque to world gears orbiting around sunlight gear. Both systems can be found inside the ring equipment. In the toothed development sun and planet gears are externally mesh and band gear internally meshes.
Planetary gear is situated in many variation and plans to meet a broad selection of speed-ratio in the deign requirements. Planetary gear system is make use of in varies applications such as, clocks, lunar calendar, car mirror, toys, gearhead engine, turbine engine and more.
For details understanding on the planetary
Planetary gear program 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 each revolution of the output carrier.
Desired number of teeth in sunlight gear is 24.
Design requirements:
Ratio = 5:1
Sun gear = 24
Module = 1
Since, I am working in the metric device every dimension will be in mm. Selecting gears in metric unit the gear tooth profile of the spur equipment will be in Module.
M = Module
N = Number of teeth
Nr = Amount of teeth on the band gear
Pd= Pitch Diameter
R = Ratio
PDs=N/M=24/1=24mm Eq. 01
Pitch diameter of the sun gear is 24.
Calculate the number if teeth necessary 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 ring gear with 96 tooth and 1 module is.
Pd=Nr/M Eq. 03 Pd=96/1=96mm
Pitch diameter of the earth gears must be found from.
PDp=(Nr-PDs)/2=(96-24)/2=72/2=36mm
Number of tooth in the planet 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.
Advantages of using planetary equipment motors in work
There are several types of geared motors that can be used in search for the perfect movement in an engineering project. Taking into account the technical specs, the required performance or space limitations of our design, you should consider to make use of one or the other. In this article we will delve on the planetary equipment motors or epicyclical equipment, which means you will know completely what its advantages are and discover some successful applications.
The planetary gear devices are seen as a having gears whose disposition is quite not the same as other models such as 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 carry up to 3 gears of the same size, which mesh with sunlight gear.
Crown or ring: an outer band (with teeth upon its inner aspect) meshes with the satellites possesses the complete epicyclical train. Furthermore, the core can also become a center of rotation for the outer ring, allowing it to easily change directions.
For accuracy and reliability, many automatic transmissions currently use planetary gear motors. If we discuss sectors this reducer provides great versatility and can be utilized in completely different applications. Its cylindrical shape is very easily adaptable to an infinite number of areas, ensuring a huge 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 devices, vending devices or robotics.
What are the main advantages of planetary gear motors?
Increased repeatability: Its better 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 boosts the accuracy and reliability of the movement.
Lower noise level since there is more surface contact. Rolling is a lot softer and jumps are practically nonexistent.
Greater durability: Because of its torsional rigidity and better rolling. To boost this feature, your bearings lessen the losses that would take place by rubbing the shaft on the container directly. Thus, greater efficiency of the gear and a much smoother operation is achieved.
Very good degrees of efficiency: Planetary reducers provide greater efficiency and because of its design and internal layout losses are minimized during their work. In fact, today, this kind of drive mechanisms are those that provide greater efficiency.
Increased torque transmission: With more teeth connected, the mechanism has the capacity to transmit and withstand more torque. In addition, it does 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 instance:
Planetary reducers offer 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 pieces handle.
They are highly efficient with an individual stage typically 95% efficient.
These reducers provide for ratios as high as 11:1 to be performed in a single stage, whereas, it is tough to achieve higher than 5:1 in a single parallel axis stage.
Because the sun gear contacts multiple world 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 allow for coaxial alignment, meaning no offset result shaft with regards to the motor shaft.
The output shaft upon Planetary reducers rotates in the same direction because the motor without needing an idler gear, because in a parallel axis gear set.
Planetary reducers are perfect for intermittent duty applications but also can be used in continuous duty applications.
Finally, Ever-Power planetary’s possess an integrated housing, meaning the ring gear is built-into the external housing for the gearbox, increasing the robusticity.
Compared to the advantages 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).
Potentially high cost if low backlash, high precision gearing is necessary.
Specific amounts of gear teeth are necessary equally spaced planets (ease of assembly) and noise mitigation.
The gear ratio determines just how many planet gears can be utilized.
You should think about planetary reducers when designing for applications requiring high torques in a small package with an output shaft needs to be co-axially aligned with the engine.
Product Overview
Product Usage:
All Ever-Power gearboxes require grease for proper procedure and extended life. We suggest using our red tacky grease, am-2768. We also encourage that the user powers the gearbox continuously for thirty minutes without grease to permit the apparatus teeth to put on in. While we perform style with short run situations in mind, this ‘run in’ period for smooth gearbox operation, is recommended. Once that is completed, thorough grease of the apparatus teeth periodically to make sure smooth operation.
Single speed planetary gearbox, with the same mounting and output interface as a 2.5″ CIM motor. Each planet equipment 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 gear ( am-0556) and a CIM Spacer (am-0555).
Motor Input:
9015 motor fits on this gearbox
550 motor fits on this gearbox
2.5″ CIM Motor can be installed, with a bored-out sun equipment and a spacer
Included Hardware:
Two – 8mm id ball bearings, (19mm od, 22mm od) supporting output shaft
One – Steel planet and sun gears, 32 dp, 20 level 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 input being truly 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 electric motor shaft.
Specifications
Material: body is usually aluminum, shaft is 4140 steel
Mounting Holes: #10-32 tapped holes (2), on a 2″ bolt circle to add at output shaft
Outside 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 program (or Epicyclic system since it can be known), consists normally of a centrally pivoted sunlight gear, a ring equipment and several planet gears which rotate between these.
This assembly concept explains the word planetary transmission, as the earth gears rotate around sunlight gear as in the astronomical sense the planets rotate around our sun.
The advantage of a planetary transmission depends upon load distribution over multiple planet gears. It is thereby feasible to transfer high torques utilizing a compact design.
Gear assembly 1 and equipment assembly 2 of the Ever-Power 500/14 possess two selectable sunlight gears. The first equipment step of the stepped planet gears engages with sun gear #1. The second gear step engages with sun gear #2. With sun gear 1 or 2 2 coupled to the axle,or the coupling of sunlight gear 1 with the band gear, three ratio variations are achievable with each gear assembly.
The choice between helical and spur gears in gearboxes may seem straightforward. Move with helical gears if you want the gearbox to perform as efficiently and quietly as possible. Choose spur gears when you need to increase the gearbox’s torque density or working life under higher loads.
These guidelines are mainly what you need to know when specifying traditional fixed-axis gearboxes. Just size the gearbox properly, and the decision between helical and spur gears will often be obvious for confirmed set of app requirements. With planetary gearboxes, however, the choice between helical and spur gears requires some additional thought.
Helical Gears Create Axial Forces
As you might expect from their different mesh geometries, spur and helical gears have very different loading characteristics. With their zero helix position, 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 gear mesh. They also exhibit more sliding at the idea of tooth get in touch with, adding friction forces in to the mix.
Helix angles in gearboxes usually fall in a variety of 15 to 30 degrees. As the angle increases, both axial forces and sliding get in touch with increase.
The primary reason for using helical gears may be the increased number of teeth in contact at any given time, which really is a fundamental requirement of smooth torque transmission. With their
increased contact ratio compared to spur gears, helical gears have got a lower fluctuation
of the apparatus mesh stiffness.
Helical Gears Place Greater Demand on Bearings
Since they won’t need to withstand any axial forces, spur gear bearings perform just a supporting function in the functioning of the gearbox. The bearings should just support the rotating equipment shafts, however they do not play an active part in torque transfer.
The presence of axial forces makes things very different for the bearings that support helical gears. But it’s important to make a distinction between fixed-axis and planetary gearboxes. In fixed-axis gearboxes, the additional axial forces total little more than a hassle. Gearbox designers will most likely upsize the bearings to support the additional forces.
Or, in extreme cases, they may select angular contact or tapered roller bearings, both which are made to withstand axial loads.
Space restrictions within planetary gearboxes mean that the earth gear bearings should be chosen more because of their size than their tolerance for high axial loads.
In planetary gearboxes, however, it’s a lot more difficult to create around these axial forces for just two related reasons. First, there is typically very little area in a planetary gearbox to include the kind of bulky bearings that may tolerate high axial forces.
Second, the planet gear bearings have to play an active role in torque transfer. Planetary systems split the torque insight from the sun gear amongst the earth gears, which transfer torque to a world carrier linked to the gearbox result. The bearings that support the planets on the carrier have to bear the entire brunt of this torque transfer.
And Here Is the Difficulty
The limited space within planetary gearboxes means that the bearings used for the planet gears should be chosen more because of their size than their tolerance for high axial loads. Generally, compact needle roller bearings are the most common choice in these configurations.
Needle roller bearings execute a good job with radial loads that are evenly distributed along the length of the needle. However they don’t deal with 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. So the planet sees significant tilting minute described by the axial power times equipment pitch diameter. This tilting minute produces an uneven load distribution along the needle rollers, significantly reducing the bearings’ load carrying capability and lifecycle.
Loads on the roller bearings will change, depending on their placement around the shaft. Minute is approximately the Z-axis, and products are in ins and pounds.
The Planetary Motion Is The Basic principle For The Planetary Gearbox.
The Accurately Positioned And Meshed Planet Gears (3) With The Sun Gear AT THE HEART And THE INNER Teeth Of The Outer Ring Gear Compose Each Stage Of A Planetary Gearbox.
The Sun Equipment Gets The Input AS THE 3 Planet Gears SUPPLY THE Ouput Via A Planet Carrier .
The Torque Handling Capability Is Very High DUE TO THE Flexibility , And AN EXTREMELY High Weight /Volume Ratio , Thus It Lends Its Program In Various Industries – Specifically In High Torque Requirements Making It The Most Economical Remedy.
Being A Proud Supplier Of Planetary Gearbox, We Provide An Excellent Distinguished Service To Our Clientile.
Planetary Gearbox Product Specs :
Provides High Torque At Slow Speeds.
Our SELECTION OF Gearboxes And Geared Motors Are Manufactured ACCORDING TO The American Gear Producers Association (AGMA) Standards.
The Shafts Are Made Up 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 Steel.
Best Load Sharing DUE TO Accurate Positioning Of Planets.
Low Noise Levels.
No Oil Leakage.
TOP QUALITY Taper Roller Bearings For Insight And Output Shafts.
Very High Efficiency