planetary gears also refer since epicyclic gearing consisting 3 elements sun gear, planet gear and ring gear. Sun gear is situated at the center that transmits torque to planet gears orbiting around the sun gear. Both systems can be found inside the ring gear. In the toothed formation sun and world gears are externally mesh and ring gear internally meshes.
Planetary gear is found in many variation and plans to meet up a broad selection of speed-ratio in the deign requirements. Planetary equipment system is make use of in varies applications such as for example, clocks, lunar calendar, car mirror, toys, gearhead electric motor, turbine engine and many more.
For details understanding on the planetary
Planetary gear program 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 be in mm. Choosing gears in metric unit the gear tooth profile of the spur equipment will maintain Module.
M = Module
N = Number of teeth
Nr = Amount 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 needed in the ring equipment 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 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 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 gear motors in your projects
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 specs, the mandatory 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 gear motors or epicyclical equipment, so you will know thoroughly what its advantages are and find out some successful applications.
The planetary gear products are characterized by having gears whose disposition is very different from 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 gear. It has a larger size and rotates on the central axis.
The earth carrier: Its objective is to hold up to 3 gears of the same size, which mesh with sunlight gear.
Crown or band: an outer band (with teeth on its inner side) meshes with the satellites and contains the whole 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 automatic transmissions currently use planetary equipment motors. If we talk about sectors this reducer offers great versatility and can be used in completely different applications. Its cylindrical shape is easily adaptable to an infinite number of areas, ensuring a big reduction in an extremely contained space.
Regularly this kind of drives can be used in applications that want higher levels of precision. For instance: Industrial automation machines, vending devices 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 gear. In addition, uniform tranny and low vibrations at different loads give a perfect repeatability.
Perfect 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 virtually nonexistent.
Greater durability: Because of its torsional rigidity and better rolling. To boost this feature, your bearings lessen the losses that would occur by rubbing the shaft on the package directly. Thus, greater performance of the gear and a much smoother procedure 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. Actually, today, this kind of drive mechanisms are those that provide greater efficiency.
Improved torque transmission: With more teeth in contact, the mechanism will be able to transmit and endure more torque. In addition, it does it in a more uniform manner.
Maximum versatility: The mechanism is within a cylindrical gearbox, which can be installed in nearly every space.
The construction of the planetary reducer lends itself to many advantages, for example:
Planetary reducers offer you high torque in a compact package; sharing the load between several world gears allows the reducer to handle the same torque that larger 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 challenging 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 output shaft with regards to the motor shaft.
The output shaft on 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 constant duty applications.
Finally, Ever-Power planetary’s possess an integrated housing, meaning the ring gear is integrated into the external housing for the gearbox, increasing the robusticity.
Compared to the benefits of the planetary reducers, the disadvantages are minimal for some applications for example:
High ratio of length to diameter when working with multiple stages (gearhead can get very long).
Possibly high cost if low backlash, high precision gearing is necessary.
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 can be utilized.
You should think about planetary reducers when making for applications requiring high torques in a small package with an result shaft must be co-axially aligned with the electric motor.
Product Overview
Product Usage:
All Ever-Power gearboxes require grease for proper operation and long life. We recommend using our reddish colored tacky grease, am-2768. We also motivate that the user powers the gearbox consistently for thirty minutes without grease to allow the gear teeth to use in. While we perform style with short run moments at heart, this ‘run in’ period for smooth gearbox procedure, is recommended. Once this is completed, comprehensive grease of the apparatus teeth periodically to ensure smooth operation.
Solitary speed planetary gearbox, with the same installation 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 could 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 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 band 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 Just before pressing the pinion equipment onto the motor shaft.
Specifications
Material: body is 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 system (or Epicyclic system as it can be 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 planet gears rotate around sunlight 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 really is thereby feasible to transfer high torques employing a compact design.
Gear assembly 1 and equipment assembly 2 of the Ever-Power 500/14 have two selectable sunlight gears. The first equipment 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 variations are achievable with each equipment assembly.
The choice between helical and spur gears in gearboxes may seem straightforward. Move with helical gears if you would like the gearbox to perform as efficiently and quietly as feasible. Choose spur gears when you need to increase the gearbox’s torque density or functioning existence under higher loads.
These guidelines are mainly what you ought 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 a given set of application requirements. With planetary gearboxes, however, the decision 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 position, spur gears absence 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 point of tooth get in touch with, 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 contact increase.
The main reason for using helical gears is the increased number of teeth in contact at any given time, which is a fundamental requirement for smooth torque transmission. With their
increased contact ratio in comparison to spur gears, helical gears have a lower fluctuation
of the apparatus mesh stiffness.
Helical Gears Place Better Demand on Bearings
Since they won’t need to withstand any axial forces, spur gear bearings play just a supporting role in the functioning of the gearbox. The bearings simply need to support the rotating gear 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’s important to make a distinction between fixed-axis and planetary gearboxes. In fixed-axis gearboxes, the excess axial forces amount to little more than an inconvenience. Gearbox designers will often upsize the bearings to support 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 restrictions within planetary gearboxes imply that the planet gear bearings should be chosen more for their 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 just two related reasons. First, there is typically very little room in a planetary gearbox to incorporate the kind of bulky bearings that may tolerate high axial forces.
Second, the planet gear bearings have to play an active part in torque transfer. Planetary systems split the torque insight from sunlight gear amongst the planet gears, which in turn transfer torque to a world carrier linked to the gearbox result. The bearings that support the planets on the carrier have to bear the full brunt of this torque transfer.
And This is actually the Difficulty
The limited space within planetary gearboxes means that the bearings used for the earth gears should be chosen more because of their size than their tolerance for high axial loads. Generally, compact needle roller bearings are the most typical choice in these configurations.
Needle roller bearings execute a good work with radial loads that are evenly distributed along the length of the needle. But 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 instant described by the axial push times gear pitch diameter. This tilting minute creates an uneven load distribution along the needle rollers, drastically reducing the bearings’ load transporting capability and lifecycle.
Loads on the roller bearings will vary, depending on their placement around the shaft. Instant is about the Z-axis, and products are in in . and pounds.
The Planetary Motion Is The Theory 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 Capacity Is Very High DUE TO THE Flexibility , And A Very 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 Specs :
Provides High Torque At Slow Speeds.
Our Range Of Gearboxes And Geared Motors Are Manufactured ACCORDING TO The American Gear Producers Association (AGMA) Standards.
The Shafts ARE MADE Of Hardened And Tempered Special Alloy Steel.
Sun And World Gears ARE MADE FROM Case Carburised And Surface 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.
Good Quality Taper Roller Bearings For Input And Output Shafts.
Very High Efficiency