planetary gears also refer since epicyclic gearing consisting three elements sun gear, planet gear and ring gear. Sunlight gear is located at the center that transmits torque to planet gears orbiting around sunlight gear. Both systems are located inside the ring gear. In the toothed formation sun and world gears are externally mesh and ring 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 many more.
For detail understanding on the planetary
Planetary gear system will no assemble unless the number of teeth in each equipment is selected properly.
Planetary spur gear drive ratio 5:1 means sunlight equipment must make 5 revolutions for every revolution of the result 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 device every dimension will maintain mm. Choosing gears in metric unit the gear tooth profile of the spur equipment will maintain Module.
M = Module
N = Number of teeth
Nr = Number of teeth on the band 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 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 band gear with 96 tooth 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 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.
Benefits of using planetary gear motors in your projects
There are several types of geared motors that can be utilized in search for an ideal movement in an engineering project. Considering the technical specifications, the required performance or space restrictions 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 equipment, so you will know completely what its advantages are and discover some successful applications.
The planetary gear units are seen as a having gears whose disposition is quite 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 carry up to 3 gears of the same size, which mesh with the sun gear.
Crown or band: an outer ring (with teeth upon its inner part) meshes with the satellites possesses the complete epicyclical train. Furthermore, the core may also become a middle of rotation for the outer ring, allowing it to easily change directions.
For accuracy and reliability, many automated transmissions currently use planetary equipment motors. If we discuss sectors this reducer offers great versatility and can be used in very different applications. Its cylindrical form is quickly adaptable to thousands of areas, ensuring a large reduction in a very contained space.
Regularly this type of drives can be utilized in applications that want higher degrees of precision. For instance: Industrial automation devices, vending machines or robotics.
What are the main benefits of planetary gear motors?
Increased repeatability: Its better speed radial and axial load offers reliability and robustness, minimizing the misalignment of the gear. In addition, uniform tranny and low vibrations at different loads give a perfect repeatability.
Ideal precision: Most rotating angular stability boosts the accuracy and reliability of the movement.
Lower noise level since there is more surface contact. Rolling is much softer and jumps are virtually nonexistent.
Greater durability: Because of its torsional rigidity and better rolling. To improve this feature, your bearings lessen the losses that could happen by rubbing the shaft on the container directly. Thus, greater performance of the apparatus and a much smoother procedure is achieved.
Very good levels of efficiency: Planetary reducers offer 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 offer greater efficiency.
Improved torque transmission: With more teeth connected, the mechanism has the capacity to transmit and endure more torque. Furthermore, it does it in a far more uniform manner.
Maximum versatility: The mechanism is contained in a cylindrical gearbox, which may be installed in almost any space.
The construction of the planetary reducer lends itself to many advantages, for example:
Planetary reducers give you high torque in a concise package; sharing the strain between several planet gears allows the reducer to handle the same torque that larger parallel axis gear pieces 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 higher than 5:1 in one 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 enable coaxial alignment, meaning no offset result shaft with regards to the motor shaft.
The output shaft upon Planetary reducers rotates in the same direction since the motor without needing an idler equipment, because in a parallel axis equipment set.
Planetary reducers are well suited for intermittent duty applications but also can be utilized in constant duty applications.
Finally, Ever-Power planetary’s have a built-in housing, meaning the ring gear is integrated into the outer housing for the gearbox, adding to the robusticity.
Compared to the benefits of the planetary reducers, the disadvantages are minimal for most applications for instance:
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 necessary.
Specific amounts of gear teeth are needed equally spaced planets (simple assembly) and noise mitigation.
The gear ratio determines just how many planet gears can be utilized.
You should think about planetary reducers when making for applications requiring high torques in a little package with an result shaft needs to be co-axially aligned with the electric motor.
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 motivate that an individual powers the gearbox constantly for thirty minutes without grease to allow the apparatus teeth to use in. While we do design with short run instances at heart, this ‘run in’ period for smooth gearbox procedure, is recommended. Once that is completed, thorough grease of the apparatus teeth periodically to make sure smooth operation.
Solitary speed planetary gearbox, with the same installation 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 could 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 level p.a.
Five – Planet gears (12 tooth)
One – 15 tooth sunlight 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 aluminium plate to the facial skin of the motor Just before pressing the pinion gear onto the motor shaft.
Specifications
Material: body is aluminum, shaft is 4140 steel
Mounting Holes: #10-32 tapped holes (2), upon 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 system (or Epicyclic system since it is also known), consists normally of a centrally pivoted sun gear, a ring gear and several world gears which rotate between these.
This assembly concept explains the term 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 have two selectable sun gears. The first gear step of the stepped planet gears engages with sunlight gear #1. The second equipment step engages with sunlight gear #2. With sunlight gear one or two 2 coupled to the axle,or the coupling of sun gear 1 with the band gear, three ratio variants are achievable with each equipment assembly.
The choice between helical and spur gears in gearboxes may seem straightforward. Proceed with helical gears if you would like the gearbox to run as easily and quietly as feasible. Choose spur gears if you want to increase the gearbox’s torque density or operating existence under higher loads.
These guidelines are mainly what you should know when specifying traditional fixed-axis gearboxes. Just size the gearbox properly, and the choice between helical and spur gears may also be obvious for a given set of application requirements. With planetary gearboxes, however, the choice 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 features. With their zero helix angle, spur gears lack an axial load element. And they suffer from very little 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 into the mix.
Helix angles in gearboxes usually fall in a variety of 15 to 30 degrees. As the angle increases, both the axial forces and sliding get in touch with increase.
The primary 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 got a lower fluctuation
of the gear mesh stiffness.
Helical Gears Place Higher Demand on Bearings
Since they don’t need to withstand any axial forces, spur gear bearings enjoy just a supporting part in the functioning of the gearbox. The bearings should just support the rotating equipment shafts, however they do not really 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 important 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 often upsize the bearings to accommodate the additional forces.
Or, in acute cases, they could select angular get in touch with or tapered roller bearings, both which are designed to withstand axial loads.
Space limitations 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 create around these axial forces for two related reasons. 1st, there is typically hardly any area in a planetary gearbox to incorporate the kind of bulky bearings that may tolerate high axial forces.
Second, the earth gear bearings have to play an active part in torque transfer. Planetary systems split the torque insight from the sun gear amongst the planet gears, which in turn transfer torque to a world carrier connected to the gearbox result. The bearings that support the planets on the carrier need to bear the entire brunt of this torque transfer.
And This is actually the Difficulty
The limited space within planetary gearboxes implies that the bearings used for the earth gears must be chosen more for his or her size than their tolerance for high axial loads. Generally, compact 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. 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-band gear mesh. Therefore the planet sees significant tilting minute described by the axial pressure times equipment pitch diameter. This tilting moment creates an uneven load distribution along the needle rollers, drastically decreasing the bearings’ load holding capability and lifecycle.
Loads on the roller bearings will change, depending on their position around the shaft. Moment is about the Z-axis, and products are in ins and pounds.
The Planetary Motion Is The Principle For The Planetary Gearbox.
The Accurately Positioned And Meshed World Gears (3) With The Sun Gear In The Centre 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 WITH 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 RENDERING IT The Most Economical Remedy.
Being A Proud Provider Of Planetary Gearbox, WE OFFER A FANTASTIC Distinguished Service TO YOUR Clientile.
Planetary Gearbox Product Specifications :
Provides High Torque In Slow Speeds.
Our Range Of Gearboxes And Geared Motors Are Manufactured As Per The American Gear Manufacturers Association (AGMA) Standards.
The Shafts ARE MADE Of Hardened And Tempered Special Alloy Steel.
Sun And Planet Gears ARE CONSTRUCTED WITH Case Carburised And Ground Alloy Steel.
Ring Gears Are Made Up Of Forged Alloy Metal.
Best Load Sharing DUE TO Accurate Positioning Of Planets.
Low Noise Levels.
No Oil Leakage.
TOP QUALITY Taper Roller Bearings For Input And Output Shafts.
Very High Efficiency