Planetary Gearbox

planetary gears also refer because epicyclic gearing consisting three elements sun gear, planet gear and ring gear. Sun gear is located at the center that transmits torque to world gears orbiting around the sun gear. Both systems can be found inside the ring equipment. 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 a broad selection of speed-ratio in the deign requirements. Planetary gear system is use in varies applications such as, clocks, lunar calendar, car mirror, toys, gearhead motor, turbine engine and much more.
For details understanding on the planetary
Planetary gear system will simply no assemble unless the amount of teeth in each equipment is selected properly.
Planetary spur equipment drive ratio 5:1 means the sun equipment must make 5 revolutions for each 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 employed in the metric unit every dimension will maintain mm. Choosing gears in metric device the apparatus tooth profile of the spur equipment will be in 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 quantity 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 ring gear with 96 the teeth and 1 module is.
Pd=Nr/M Eq. 03 Pd=96/1=96mm
Pitch diameter of the earth gears should be found from.
PDp=(Nr-PDs)/2=(96-24)/2=72/2=36mm
Number of the teeth in the planet gears may now be 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 utilized in search for an ideal movement in an engineering project. Taking into account the technical specifications, the mandatory performance or space limitations of our design, you should ask yourself to make use of one or the additional. In this article we will delve on the planetary equipment motors or epicyclical gear, so you will know completely what its advantages are and find out some successful applications.
The planetary gear devices are seen as a having gears whose disposition is quite not the same as 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 sunlight gear.
Crown or ring: an outer ring (with teeth upon its inner side) meshes with the satellites possesses the whole epicyclical train. In addition, the core may also become a middle of rotation for the external ring, allowing it to easily change directions.
For accuracy and reliability, many automated transmissions currently use planetary equipment motors. If we talk about sectors this reducer provides great versatility and can be used in very different applications. Its cylindrical shape is very easily adaptable to an infinite number of areas, ensuring a large reduction in a very contained space.
Regularly this type of drives can be utilized in applications that require higher degrees of precision. For example: Industrial automation devices, vending machines or robotics.
What are the main 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 transmitting and low vibrations at different loads give a perfect repeatability.
Ideal precision: Most rotating angular stability increases 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: Due to its torsional rigidity and better rolling. To boost this feature, your bearings lessen the losses that could take place by rubbing the shaft on the box directly. Thus, greater effectiveness of the gear and a much smoother operation is achieved.
Very good degrees of efficiency: Planetary reducers provide greater efficiency and thanks to its design and internal layout losses are minimized throughout their work. Actually, today, this type of drive mechanisms are those that offer greater efficiency.
Improved torque transmission: With an increase of teeth connected, the mechanism will be able to transmit and endure 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 many advantages, for instance:
Planetary reducers offer you high torque in a concise package; sharing the load between several planet gears allows the reducer to take care of the same torque that bigger parallel axis gear units handle.
They are highly efficient with a single stage typically 95% efficient.
These reducers provide for ratios as high as 11:1 to be achieved within a stage, whereas, it is hard to achieve much higher than 5:1 in one parallel axis stage.
Because the sun gear contacts multiple world gears, 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 in relation to the motor shaft.
The output shaft on Planetary reducers rotates in the same direction because the engine without needing an idler gear, as in a parallel axis gear set.
Planetary reducers are ideal for intermittent duty applications but also can be used in constant duty applications.
Finally, Ever-Power planetary’s possess a built-in 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 disadvantages are minimal for most applications for example:
High ratio of length to diameter when working with multiple stages (gearhead will get very long).
Possibly high cost if low backlash, high precision gearing is required.
Specific numbers of gear teeth are required equally spaced planets (simple assembly) and noise mitigation.
The gear ratio determines how many planet gears may be used.
You should think about planetary reducers when designing for applications requiring high torques in a small package with an result shaft must be co-axially aligned with the motor.
Product Overview
Product Usage:
All Ever-Power gearboxes require grease for proper operation and extended life. We suggest using our reddish colored tacky grease, am-2768. We also encourage that an individual powers the gearbox continuously for thirty minutes without grease to allow the gear teeth to wear in. While we do design with short run instances in mind, this ‘run in’ period for smooth gearbox operation, is recommended. Once that is completed, comprehensive grease of the apparatus teeth periodically to ensure smooth operation.
Solitary speed planetary gearbox, with the same mounting and output interface as a 2.5″ CIM motor. Each planet equipment has its 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 upon 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 world and sun gears, 32 dp, 20 degree p.a.
Five – Planet gears (12 tooth)
One – 15 tooth sun gear, with 0.125 inch bore
One – 40 tooth ring gear
Performance Data:
(with the input being a 9015 motor)
Input voltage: 12 volts
Stall Torque: 1.12 ft-lb.
Free speed: approximately 4,000 rpm
Assembly Tip:
Install the aluminum plate to the face of the motor Prior to 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
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 as it can be known), consists normally of a centrally pivoted sunlight 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 advantage of a planetary transmission depends upon load distribution over multiple planet gears. It is thereby possible to transfer high torques utilizing a compact design.
Gear assembly 1 and gear assembly 2 of the Ever-Power 500/14 possess two selectable sunlight gears. The first gear stage of the stepped world gears engages with sunlight gear #1. The next gear step engages with sunlight gear #2. With sun gear 1 or 2 2 coupled to the axle,or the coupling of sun equipment 1 with the ring gear, three ratio variants are achievable with each equipment assembly.
The decision between helical and spur gears in gearboxes may appear straightforward. Move with helical gears if you want the gearbox to run as efficiently and quietly as feasible. Choose spur gears if you want to maximize the gearbox’s torque density or operating life under higher loads.
These guidelines are mainly what you should know when specifying traditional fixed-axis gearboxes. Simply size the gearbox properly, and the choice between helical and spur gears will often be obvious for confirmed set of program requirements. With planetary gearboxes, however, the decision between helical and spur gears requires some extra thought.
Helical Gears Create Axial Forces
As you may expect from their different mesh geometries, spur and helical gears have very different loading characteristics. With their zero helix angle, spur gears absence an axial load component. And they suffer from very little sliding tooth contact.
Helical gears, in comparison, generate significant axial forces in the apparatus mesh. They also exhibit more sliding at the idea of tooth contact, adding friction forces into the mix.
Helix angles in gearboxes usually fall in a variety of 15 to 30 degrees. As the position increases, both the axial forces and sliding get in touch with increase.
The primary reason for using helical gears may be 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 apparatus mesh stiffness.
Helical Gears Place Greater Demand on Bearings
Since they don’t need to withstand any axial forces, spur gear bearings perform just a supporting role in the functioning of the gearbox. The bearings should just support the rotating gear shafts, but they do not really play an active part in torque transfer.
The existence of axial forces makes things very different for the bearings that support helical gears. But it is important to make a distinction between fixed-axis and planetary gearboxes. In fixed-axis gearboxes, the excess axial forces amount to little more than a hassle. Gearbox designers will often upsize the bearings to accommodate the additional forces.
Or, in extreme cases, they may select angular contact or tapered roller bearings, both which are designed to withstand axial loads.
Space limitations within planetary gearboxes mean that the earth gear bearings must be chosen more because of their size than their tolerance for high axial loads.
In planetary gearboxes, however, it’s much more difficult to create around these axial forces for two related reasons. 1st, there is typically very little room in a planetary gearbox to include the type of bulky bearings that may tolerate high axial forces.
Second, the earth gear bearings have 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 planet carrier linked to the gearbox result. The bearings that support the planets on the carrier need to bear the entire brunt of that torque transfer.
And This is actually 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. In general, small needle roller bearings are the most typical choice in these settings.
Needle roller bearings do a good work with radial loads that are evenly distributed along the distance of the needle. However they don’t manage 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-band gear mesh. So the planet sees significant tilting minute described by the axial drive times equipment pitch diameter. This tilting second creates an uneven load distribution along the needle rollers, significantly reducing the bearings’ load having capability and lifecycle.
Loads on the roller bearings will vary, depending on their position around the shaft. Second is approximately the Z-axis, and devices are in inches and pounds.
The Planetary Motion Is The Theory For The Planetary Gearbox.
The Accurately Positioned And Meshed World Gears (3) With The Sun Gear In The Centre And The Internal Teeth Of The Outer Ring Gear Compose Each Stage Of A Planetary Gearbox.
The Sun Equipment Gets The Input AS THE 3 Planet Gears Provide The Ouput Via A Planet Carrier .
The Torque Handling Capability Is Very High DUE TO ITS Flexibility , And A Very High Weight /Volume Ratio , Thus It Lends Its Program In Various Industries – Specifically In High Torque Requirements Making It The Most Economical Answer.
Being A Proud Supplier Of Planetary Gearbox, We Provide An Excellent Distinguished Service TO YOUR Clientile.
Planetary Gearbox Product Specs :
Provides High Torque In 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 Special Alloy Steel.
Sun And Planet Gears Are Made Of Case Carburised And Floor Alloy Steel.
Ring Gears ARE MADE 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