planetary gears also refer because epicyclic gearing consisting 3 components sun gear, planet gear and ring gear. Sun gear is situated at the guts that transmits torque to planet gears orbiting around the sun gear. Both systems can be found inside the ring equipment. In the toothed development sun and planet gears are externally mesh and ring gear internally meshes.
Planetary gear is found in many variation and arrangements to meet a broad range 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 motor, turbine engine and many more.
For fine 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 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 unit every dimension will be in mm. Choosing gears in metric unit the gear tooth profile of the spur gear will be in Module.
M = Module
N = Number of teeth
Nr = Quantity 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 quantity if teeth necessary 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 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 teeth in the planet gears may now become 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 plenty of 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 restrictions of our design, you should ask yourself to use one or the various other. In this post we will delve on the planetary equipment motors or epicyclical equipment, so you will know thoroughly what its advantages are and discover some successful applications.
The planetary gear products 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 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 the sun gear.
Crown or band: an outer band (with teeth upon its inner part) meshes with the satellites possesses the complete epicyclical train. In addition, the core may also become a middle of rotation for the outer ring, and can easily change directions.
For accuracy and reliability, many automated transmissions currently use planetary equipment motors. If we discuss sectors this reducer provides great versatility and can be utilized in completely different applications. Its cylindrical shape is easily adaptable to thousands of spaces, ensuring a big reduction in an extremely contained space.
Regularly this type of drives can be utilized in applications that require higher levels of precision. For instance: Industrial automation devices, vending devices 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 provide a perfect repeatability.
Perfect precision: Most rotating angular stability improves the accuracy and reliability of the movement.
Lower noise level because there is more surface area contact. Rolling is much softer and jumps are virtually nonexistent.
Greater durability: Due to its torsional rigidity and better rolling. To boost this feature, your bearings help reduce the losses that would occur by rubbing the shaft on the container directly. Thus, greater efficiency of the gear and a much smoother operation is achieved.
Very good levels of efficiency: Planetary reducers provide greater efficiency and because of its design and internal layout losses are minimized throughout their work. Actually, today, this kind of drive mechanisms are those that provide greater efficiency.
Improved torque transmission: With an increase of teeth in contact, the mechanism can transmit and endure more torque. Furthermore, it can 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 instance:
Planetary reducers offer you high torque in a compact package; sharing the strain between several world gears allows the reducer to handle the same torque that larger parallel axis gear models handle.
They are highly efficient with an individual stage typically 95% efficient.
These reducers give 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 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 as the motor without needing an idler equipment, since in a parallel axis gear set.
Planetary reducers are ideal 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 integrated 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 working with multiple stages (gearhead can get very long).
Potentially 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 gear ratio determines how many planet gears may be used.
You should look at 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 suggest using our red tacky grease, am-2768. We also motivate that an individual powers the gearbox continually for 30 minutes without grease to allow the gear teeth to put on in. While we do design with short run instances in mind, this ‘run in’ period for smooth gearbox operation, 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 bearing to spin freely on the carrier plate pins. A 2.5″ CIM Motor may also be used as the motor input, but needs this pinion gear ( 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 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 planet and sun gears, 32 dp, 20 level p.a.
Five – Planet gears (12 tooth)
One – 15 tooth sun gear, with 0.125 inch bore
One – 40 tooth band gear
Performance Data:
(with the insight 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 aluminum plate to the face of the motor Prior to pressing the pinion equipment onto the electric 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
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 as 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 term 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 is determined by load distribution over multiple planet gears. It is thereby possible to transfer high torques employing a compact design.
Gear assembly 1 and gear 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 sun gear 1 or 2 2 coupled to the axle,or the coupling of sunlight gear 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. Go with helical gears if you want the gearbox to perform as easily and quietly as possible. Choose spur gears if you want to increase the gearbox’s torque density or operating lifestyle under higher loads.
These rules of thumb are mainly what you should 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 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 element. And they suffer from very little sliding tooth contact.
Helical gears, by contrast, generate significant axial forces in the apparatus mesh. In addition they 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 range 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 connected 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 possess 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 equipment shafts, but they do not really play an active function in torque transfer.
The presence of axial forces makes things completely 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 a hassle. Gearbox designers will most likely upsize the bearings to support the additional forces.
Or, in extreme cases, they may select angular get in touch with or tapered roller bearings, both of which are designed to withstand axial loads.
Space restrictions within planetary gearboxes mean that the earth gear bearings must 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 just two related reasons. 1st, there is typically hardly any area in a planetary gearbox to incorporate the type of bulky bearings that can tolerate high axial forces.
Second, the planet gear bearings need to play an active part in torque transfer. Planetary systems split the torque input from sunlight gear amongst the planet gears, which in turn transfer torque to a planet carrier linked to the gearbox output. The bearings that support the planets on the carrier have to bear the full 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 must be chosen more because of their size than their tolerance for high axial loads. Generally, small 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 distance 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. Therefore the world sees significant tilting minute described by the axial pressure times equipment pitch diameter. This tilting instant creates 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. Moment is about the Z-axis, and products are in in . and pounds.
The Planetary Motion MAY BE THE Theory 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 Band 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 Application In Various Industries – Specifically In High Torque Requirements RENDERING IT The Most Economical Alternative.
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 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 Particular Alloy Steel.
Sun And Planet Gears ARE MADE FROM Case Carburised And Surface 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.
Good Quality Taper Roller Bearings For Input And Output Shafts.
Very High Efficiency