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Best epicyclic gearbox – EPG China manufacturer and supplier with high quality and best prices

Gearbox epicyclic

gearbox epicyclic

Epicyclic Gearbox

An epicyclic gear train consists of two helical-shaped gears, mounted so that the centers of one revolve around the center of the other. The two gears are connected with a carrier. These gears mesh so that the pitch circles roll without slipping. The epicyclic gear train is one of the most common types of gearboxes. This type of gear train is found in a variety of different applications, including bicycles, motorcycles, and cars.

planetary gear train

An epicyclic gear train has several features unique to a planetary gear set. It can create an incredible range of gear reductions, which are necessary to make the vehicle roll smoothly. A planetary gear train is usually composed of two shafts, one that comes from the engine and the other that connects to the driven wheels. This configuration is also used in auto transmissions, hoists, pulley blocks, wristwatches, and other applications.

Planetary gears minimize the baseplate size, allowing the input and output shafts to be in the same axial plane. However, they require many additional gears and bearings, which can significantly reduce their reliability and extend their MTTR. This type of gearbox is more expensive than its counterparts and is often associated with higher MTTR. However, the efficiency of this geartrain is well worth the cost, as their MTTRs are well over 99.5%.

The main principle of a planetary gear train is that the input drive passes through the sun gear, while the output drive is transferred via a ring gear. Each gear has a number of teeth, and the number of teeth determines the relative speeds. However, coupled epicyclic gears are not without their challenges, including relative speeds between the sun and planet. A fixed sun does not have a constant speed, and thus the ratio between the two must be calculated.

A planetary gear train has three main types, depending on the power transmitted to each gear. The basic type is a highly efficient planetary gearbox, transmitting 97% of the power input to the output. There are also several variations of planetary gearboxes, such as the epicyclic and helical. If you’re planning a new transmission for a vehicle, consider an epicyclic gearbox.

Compound planets

The components of an epicyclic gearbox include the sun, carrier, planets, and ring. The sun acts as the center gear and is connected to the other gears by an axis called the carrier. Planet gears rotate on shafts and orbit the sun. The ring acts as the internal gear. The ring is the largest part of an epicyclic gearbox and is the most complex component.

The compound planets of an epicyclic gearbox are arranged with different-sized gears on either end of the common casting. The large gear engages the sun, while the smaller gear engages the annulus. The compound planets may be used to achieve smaller step changes in gear ratios. These gears are equipped with timing marks that indicate the correct orientation. If these components are not installed properly, the compound planets will cause the gearbox to run unevenly and have a short life span.

The free-body diagram of the epicyclic arrangement shows the torque distribution among the planets. In addition, it explains the 60 percent efficiency of a recirculating set. The sun gear and planet gears are rigidly coupled with each other. A force at the sun gear mesh results in an output torque that is 41.1 times the input torque. The result is a high efficiency gearbox. If you’re interested in learning more about epicyclic gears, read on!

When designing an epicyclic gearbox, be sure to keep the mesh power in mind. A tight location can create a less than optimal power transfer, while an open position will maximize load sharing. If you’re interested in the efficiency of an epicyclic gearbox, you should also check out the ASME Paper 68-MECH-45 by P.W. Jensen. When designing an epicyclic gearbox, make sure the annulus and sun gears have “float”.

Perlengkapan matahari

gearbox epicyclic

The epicyclic arrangement consists of two different sized gears, the Sun gear and the annulus gear, with the former engaging the sun. Because the two gears are not perfectly balanced, slight differences in the radial positions of the planets can have a significant impact on their ratios. In some designs, proper alignment of the planet pins is critical to the correct functioning of the gearbox. If the planets are positioned improperly, they may cause rough running and shorten the gearbox’s lifespan.

The Sun gear in an epicyclic gear train is attached to a primary pulley drive shaft. The epicyclic gear train consists of an input planetary carrier, which supports three sets of double planetary gears. The input planetary carrier surrounds the planetary gears with an internally toothed annulus gear that supports rotating reverse brake plates. The Sun gear is attached to the primary pulley drive shaft and is attached to the planet carrier. In the park or neutral position, the sun gear, planet gear, and ring gear revolve around each other, enabling them to apply load to the carrier.

The sun gear in an epicyclic gearbox is connected to the planetary gears by a connecting annulus. The outer planet gears rotate at a rate determined by the number of teeth on each. Thus, a sun gear with S teeth and a planet gear with P teeth have a ratio of -S/P, which means that each planet gear produces 1.5 counterclockwise turns. This allows the epicyclic gear train to provide a high torque to the wheels.

A planetary gearbox with a sun-gear carrier achieves the second highest transmission ratio. The input and output of the epicyclic gearbox must be identical to obtain the highest transmission ratio. If this is done, the ring gear will shift from its position in the epicyclic gearbox to the output position. The reverse position will produce a negative transmission ratio. And vice versa. This is the only way to reverse the direction of rotation of the output and input shafts.

Number of planets

Best epicyclic gearbox - EPG China manufacturer and supplier with high quality and best prices new epicyclic gearbox 2

A planetary gear train is a type of transmission with more than one mesh. The epicyclic gears are made up of three sets of double planetary gears, each containing a sun and planet. They rotate around a sun gear. The ring gear, the sun gear, and the planet gear are connected by a primary pulley drive shaft. When a car is in park or neutral, the multiple clutches and brakes are disengaged. The planetary gears rotate around the sun gear, without transmitting any power to the primary pulley shaft.

ANSI-AGMA 6123-B06 addresses load sharing in epicyclic gear drives. Because the number of planets in an epicyclic gear drive may differ, the tangential load on each gear is not distributed equally along the different load paths. As a result, an epicyclic gear drive incorporates a mesh load factor to compensate for the imbalance in the load distribution. The mesh load factor equals -S/P and -3/2, so one clockwise turn of the sun gear produces 1.5 counterclockwise turns of the planet gears.

The number of planets in epicyclic gearing is not fixed, and it can be a complex system. Each gear has many parts, but only a few work in tandem. The outer planet gears rotate in a clockwise direction, while the inner planet gears rotate in a counterclockwise direction. The sun gear, however, moves in the opposite direction to the outer planet gears. In this way, the whole system works by transferring motion from the outer planet gears to the sun gear.

As the number of planets in an epicyclic gearbox increases, the planetary ratio also increases. The “effective” number of planets is equal to the actual number of planets in an epicyclic gearbox with more than three planets. When calculating the effective number of planets in an epicyclic gearbox, the sun and the planet have different speeds. The fixed sun is in a speed relationship with each other, and it is not possible to calculate the speed of a planet without taking into account the planet’s relative speed.

Torque split in epicyclic gearbox

An epicyclic gearbox has two main types. Planetary gears and planetary carriers. A planetary gear has a 108-mm diameter and a total of 54 teeth. A planetary gear has an output speed of 333 rpm and a rotational speed of 200 rpm. An epicyclic gear box has multiple meshes and a recirculating set can work up to 60 percent efficiency.

A typical four-wheel drive arrangement uses an epicyclic gear central differential, a mechanism that splits drive torque before it reaches the planetary gears. The forward-facing drive shaft feeds power to the front differential. The input drive of the gearbox mainshaft directs power to pinions and a hollow output shaft. The torque split is achieved by the friction between the pinions and the planet carrier.

The general algorithm for calculating efficiency of epicyclic gear trains was reported in Ref. (6). Several researchers used the general formulation of kinematics and power flow to determine the efficiency of spur-gear trains. The results of this study were verified with a numerical model of an epicyclic gear train and the mathematical analysis. A general formulation of power flow and kinematic chains was developed by Kahraman et al., while the graphic representation of kinematic chains was employed by Pennestri, Mariti, and Valentini.

The main rotor of a helicopter is driven by an epicyclic gearbox. An epicyclic gearbox has two planetary gears, the rotor sun gear and the stationary sun gear. The rotor sun gear is the most heavily loaded of the two. Both planetary gears mesh with each other. Hence, the torque split is greater in the front than in the rear. This design reduces wind-up and increases the operational safety factor.

Info lebih lanjut.:

In an epicyclic or planetary gear train, several spur gears distributed evenly around the circumference run between a gear with internal teeth and a gear with external teeth on a concentric orbit. The circulation of the spur gear occurs in analogy to the orbiting of the planets in the solar program. This is how planetary gears acquired their name.
Komponen rangkaian roda gigi planet dapat dibagi menjadi empat bagian utama.
The housing with integrated internal teeth is known as the ring gear. In the majority of cases, the casing is fixed. The generating sun pinion is usually in the center of the ring gear and is coaxially organized with regard to the output. Sunlight pinion is usually mounted on a clamping system to be able to give the mechanical link with the electric motor shaft. During operation, the planetary gears, which happen to be installed on a planetary carrier, roll between your sunshine pinion and the band equipment. The planetary carrier also represents the outcome shaft of the gearbox.
The sole purpose of the planetary gears is to transfer the required torque. The quantity of teeth does not have any effect on the transmission ratio of the gearbox. The number of planets may also vary. As the quantity of planetary gears raises, the distribution of the strain increases, and then the torque can be transmitted. Raising the number of tooth engagements also reduces the rolling electricity. Since only part of the total end result has to be transmitted as rolling electricity, planetary equipment is extremely efficient. The good thing about planetary equipment compared to an individual spur gear lies in this load distribution. Hence, it is possible to transmit substantial torques wit
h efisiensi tinggi dengan desain kompak menggunakan roda gigi planet.
Provided that the ring gear has a regular size, different ratios could be realized by various the amount of teeth of the sun gear and the amount of teeth of the planetary gears. Small the sun gear, the higher the ratio. Technically, a meaningful ratio range for a planetary stage is approx. 3:1 to 10:1, because the planetary gears and sunlight gear are extremely little above and below these ratios. Higher ratios can be obtained by connecting several planetary stages in series in the same ring gear. In cases like this, we talk about multi-stage gearboxes.
With planetary gearboxes the speeds and torques could be overlaid by having a ring gear that’s not set but is driven in any direction of rotation. It is also possible to fix the drive shaft so that you can pick up the torque via the ring equipment. Planetary gearboxes have become extremely important in many areas of mechanical engineering.
They have become particularly well established in areas where high output levels and fast speeds must be transmitted with favorable mass inertia ratio adaptation. Large transmission ratios may also easily be achieved with planetary gearboxes. Because of their positive properties and small style, the gearboxes have many potential uses in commercial applications.
Fitur gearbox planet:
Susunan koaksial poros masukan dan poros keluaran
Distribusi beban ke beberapa roda gigi planet
Efisiensi tinggi karena daya gelinding rendah
Almost unlimited transmission ratio options because of combo of several planet stages
Appropriate as planetary switching gear due to fixing this or that part of the gearbox
Kemungkinan penggunaan sebagai gearbox utama
Output volume yang menguntungkan
Kesesuaian untuk berbagai aplikasi
Gearbox epicyclic is an automatic type gearbox where parallel shafts and gears arrangement from manual gear container are replaced with an increase of compact and more reputable sun and planetary kind of gears arrangement plus the manual clutch from manual electrical power train is changed with a hydro coupled clutch or torque convertor which made the transmitting automatic.
The idea of an epicyclic gear box is extracted from the solar system which is known as to an ideal arrangement of objects.
The epicyclic gearbox usually comes with the P N R D S (Parking, Neutral, Reverse, Travel, Sport) settings which is obtained by fixing of sun and planetary gears in line with the need of the travel.
Komponen Epicyclic Gearbox
1. Ring gear- It is a type of gear that looks like a ring and have angular slice teethes at its inner surface,and is placed in the outermost posture in an epicyclic gearbox, the inner teethes of the ring gear is in continuous mesh at outer stage with the set of planetary gears,it is also referred to as annular ring.
2. Sun gear- It is the equipment with angular lower teethes and is positioned in the middle of the epicyclic gearbox; sunlight gear is in continuous mesh at inner stage with the planetary gears and can be connected with the source shaft of the epicyclic gear box.
One or more sunlight gears can be used for obtaining different outputs.
3. Planet gears- These are small gears found in between band and sun gear, the teethes of the planet gears are in continuous mesh with the sun and the ring gear at both inner and outer factors respectively.
The axis of the planet gears is attached to the earth carrier which is carrying the output shaft of the epicyclic gearbox.
The earth gears can rotate about their axis and also can revolve between the ring and sunlight gear exactly like our solar system.
4. Planet carrier- This is a carrier fastened with the axis of the planet gears Best epicyclic gearbox - EPG China manufacturer and supplier with high quality and best pricesand is accountable for the final transmitting of the outcome to the productivity shaft.
The planet gears rotate over the carrier and the revolution of the planetary gears causes the rotation of the carrier.
5. Brake or clutch band- The device used to repair the annular gear, sunshine gear and planetary equipment and is manipulated by the brake or clutch of the vehicle.
Kerja Gearbox Episiklik
The working principle of the epicyclic gearbox is based on the actual fact the fixing the gears i.electronic. sun equipment, planetary gears and annular equipment is done to get the needed torque or rate output. As fixing the above causes the variation in gear ratios from substantial torque to high acceleration. So let’s observe how these ratios are obtained
Rasio gigi pertama
This provides high torque ratios to the automobile which helps the automobile to move from its initial state and is obtained by fixing the annular gear which in turn causes the planet carrier to rotate with the energy supplied to the sun gear.
Rasio gigi kedua
This gives high-speed ratios to the vehicle which helps the automobile to achieve higher speed throughout travel, these ratios are obtained by fixing sunlight gear which makes the planet carrier the powered member and annular the driving a vehicle member so that you can achieve high-speed ratios.
Rasio gigi mundur
This gear reverses the direction of the output shaft which in turn reverses the direction of the automobile, this gear is achieved by fixing the earth gear carrier which in turn makes the annular gear the motivated member and the sun gear the driver member.
Note- More acceleration or torque ratios may be accomplished by increasing the quantity of planet and sun gear in the epicyclic gear container.
High-speed epicyclic gears can be built relatively tiny as the power is distributed over several meshes. This results in low power to pounds ratio and, as well as lower pitch line velocity, leads to improved efficiency. The small equipment diameters produce lower occasions of inertia, significantly reducing acceleration and deceleration torque when starting and braking.
Desain koaksial memungkinkan fondasi yang lebih kecil dan karena alasan itu lebih hemat biaya, memungkinkan biaya bangunan tetap rendah atau seluruh genset diintegrasikan dalam wadah.
Why epicyclic gearing is utilized has been covered in this magazine, so we’ll expand on the topic is simply a few places. Let’s get started by examining a crucial facet of any project: expense. Epicyclic gearing is normally less costly when tooled properly. Being a would not consider making a 100-piece large amount of gears on N/C milling equipment with an application cutter or ball end mill, you need to certainly not consider making a 100-piece large amount of epicyclic carriers on an N/C mill. To keep carriers within realistic manufacturing costs they should be made from castings and tooled on single-purpose equipment with multiple cutters at the same time removing material.
Size is another factor. Epicyclic gear pieces are used because they’re smaller than offset equipment sets since the load is normally shared among the planned gears. This makes them lighter and smaller sized, versus countershaft gearboxes. Likewise, when configured correctly, epicyclic gear sets are more efficient. The following example illustrates these rewards. Let’s assume that we’re developing a high-speed gearbox to satisfy the following requirements:
• A turbine offers 6,000 hp at 16,000 RPM to the input shaft.
• Produktivitas dari gearbox harus menggerakkan generator pada 900 RPM.
• Gaya hidup desain harus 10,000 jam.
With these requirements at heart, let’s look at three likely solutions, one involving a single branch, a two-stage helical gear set. A second solution takes the original gear established and splits the two-stage decrease into two branches, and the 3rd calls for using a two-stage planetary or celebrity epicyclic. In this situation, we chose the star. Let’s examine each one of these in greater detail, looking at their ratios and resulting weights.
The first solution-a single branch, two-stage helical gear set-has two identical ratios, produced by taking the square root of the final ratio (7.70). In the process of reviewing this option, we realize its size and pounds are very large. To reduce the weight we then explore the possibility of making two branches of a similar arrangement, as seen in the second alternative. This cuts tooth loading and minimizes both size and fat considerably. We finally arrive at our third choice, which may be the two-stage star epicyclic. With three planets this gear train reduces tooth loading drastically from the initial approach, and a somewhat smaller amount from option two (observe “methodology” at end, and Figure 6).
The unique design characteristics of epicyclic gears are a large part of what makes them so useful, yet these very characteristics can make developing them a challenge. Within the next sections, we’ll explore relative speeds, torque splits, and meshing considerations. Our objective is to create it easily so that you can understand and work with epicyclic gearing’s unique style characteristics.
Kecepatan Relatif
Let’s get started by looking at how relative speeds operate in conjunction with different plans. In the star set up the carrier is fixed, and the relative speeds of the sun, planet, and ring are simply determined by the speed of one member and the number of teeth in each piece of equipment.
In a planetary arrangement the ring gear is set, and planets orbit sunlight while rotating on the earth shaft. In this set up the relative speeds of sunlight and planets are determined by the number of teeth in each piece of equipment and the quickness of the carrier.
Things get a bit trickier whenever using coupled epicyclic gears, since relative speeds may well not be intuitive. Hence, it is imperative to usually calculate the acceleration of sunlight, planet, and ring in accordance with the carrier. Understand that even in a solar arrangement where the sunlight is fixed it has a speed romantic relationship with the planet-it is not zero RPM at the mesh.
Pemisahan Torsi
When considering torque splits one assumes the torque to be divided among the planets equally, but this might not exactly be a valid assumption. Member support and the number of planets determine the torque split represented by an “effective” quantity of planets. This quantity in epicyclic sets constructed with two or three planets is generally equal to the actual amount of planets. When a lot more than three planets are utilized, however, the effective number of planets is generally less than you see, the number of planets.
Let’s look at torque splits with regards to set support and floating support of the users. With fixed support, all users are reinforced in bearings. The centers of the sun, band, and carrier will never be coincident due to manufacturing tolerances. Because of this fewer planets will be simultaneously in mesh, resulting in a lower effective number of planets posting the load. With floating support, one or two people are allowed a tiny amount of radial flexibility or float, which allows the sun, ring, and carrier to get a posture where their centers happen to be coincident. This float could possibly be as little as .001-.002 ins. With floating support three planets will be in mesh, producing a higher effective amount of planets sharing the load.
Beberapa Pertimbangan Mesh
At this time let’s explore the multiple mesh factors that need to be made when making epicyclic gears. Primary we must translate RPM into mesh velocities and determine the number of load request cycles per device of time for every single member. The first step in this determination is certainly to calculate the speeds of every one of the members relative to the carrier. For example, if the sun equipment is rotating at +1700 RPM and the carrier is rotating at +400 RPM the rate of the sun gear in accordance with the carrier is +1300 RPM, and the speeds of world and ring gears could be calculated by that acceleration and the numbers of teeth in each of the gears. The use of signals to stand for clockwise and counter-clockwise rotation can be important here. If the sun is rotating at +1700 RPM (clockwise) and the carrier is rotating at -400 RPM (counter-clockwise), the relative acceleration between the two participants is normally +1700-(-400), or +2100 RPM.
The next step is to decide the quantity of load application cycles. Since the sun and ring gears mesh with multiple planets, the number of load cycles per revolution in accordance with the carrier will be equal to the number of planets. The planets, however, will experience only 1 bi-directional load software per relative revolution. It meshes with sunlight and ring, but the load can be on the contrary sides of one’s teeth, resulting in one fully reversed anxiety cycle. Thus the planet is known as an idler, and the allowable stress must be reduced by 30 percent from the value for a unidirectional load software.
As noted over, the torque on the epicyclic customers is divided among the planets. In analyzing the stress and life of the users we must consider the resultant loading at each mesh. We locate the concept of torque per mesh to be relatively confusing in epicyclic equipment evaluation and prefer to look at the tangential load at each mesh. For example, in seeking at the tangential load at the sun-world mesh, we have the torque on sunlight equipment and divide it by the successful amount of planets and the functioning pitch radius. This tangential load, combined with the peripheral speed, can be used to compute the energy transmitted at each mesh and, altered by the strain cycles per revolution, the life span expectancy of every component.
In addition to these issues there can also be assembly complications that need addressing. For example, putting one planet ready between sun and band fixes the angular position of sunlight to the ring. Another planet(s) is now able to be assembled only in discreet locations where in fact the sun and band could be concurrently engaged. The “least mesh angle” from the 1st planet that will support simultaneous mesh of the next planet is equal to 360° divided by the sum of the numbers of teeth in sunlight and the ring. As a result, in order to assemble more planets, they must always be spaced at multiples of the least mesh angle. If one wants to have the same spacing of the planets in a simple epicyclic set, planets may be spaced equally when the sum of the number of teeth in sunlight and band is normally divisible by the number of planets to an integer. The same rules apply in a substance epicyclic, but the fixed coupling of the planets brings another level of complexity, and correct planet spacing may require match marking of the tooth.
With multiple elements in the mesh, losses should be considered at each mesh so as to evaluate the efficiency of the unit. Power transmitted at each mesh, not input power, must be used to compute power loss. For simple epicyclic pieces, the total ability transmitted through the sun-world mesh and ring-planet mesh may be significantly less than the input ability. This is one of the reasons that simple planetary epicyclic sets are better than other reducer arrangements. In contrast, for many coupled epicyclic models total electrical power transmitted internally through each mesh may be greater than the input power.
What of electric power at the mesh? For simple and compound epicyclic sets, calculate pitch collection velocities and tangential loads to compute electricity at each mesh. Values can be obtained from the earth torque relative acceleration and the operating pitch diameters with sunlight and band. Coupled epicyclic sets present more technical issues. Elements of two epicyclic pieces could be coupled in 36 different ways using one input, one output, and one reaction. Some arrangements split the power, while some recirculate ability internally. For these types of epicyclic models, tangential loads at each mesh can only just be established through the use of free-body diagrams. On top of that, the elements of two epicyclic models could be coupled nine various ways in a series, using one source, one end result, and two reactions. Let’s look at a few examples.
In the “split-electrical power” coupled set proven in Figure 7, 85 percent of the transmitted vitality flows to band gear #1 and 15 percent to band gear #2. The result is that this coupled gear set can be smaller sized than series-coupled units because the electrical power is split between the two elements. When coupling epicyclic pieces in a series, 0 percent of the power will become transmitted through each established.
Our next example depicts a arrangement with “ability recirculation.” This gear set happens when torque gets locked in the machine in a manner similar to what happens in a “four-square” test process of vehicle drive axles. With the torque locked in the system, the hp at each mesh within the loop enhances as speed increases. Consequently, this set will encounter much higher electrical power losses at each mesh, leading to considerably lower unit efficiency.
Body 9 depicts a free-body diagram of a great epicyclic arrangement that encounters power recirculation. A cursory evaluation of this free-body diagram explains the 60 percent productivity of the recirculating arrangement demonstrated in Figure 8. Since the planets happen to be rigidly coupled jointly, the summation of forces on the two gears must the same zero. The induce at sunlight gear mesh affects the torque source to the sun gear. The power at the next ring gear mesh effects by the productivity torque on the ring gear. The ratio being 41.1:1, productivity torque is 41.1 times input torque. Adjusting for a pitch radius big difference of, say, 3:1, the power on the next planet will be approximately 14 times the force on the first world at sunlight gear mesh. For that reason, for the summation of forces to mean zero, the tangential load at the first band gear should be approximately 13 occasions the tangential load at the sun gear. If we presume the pitch line velocities to become the same at the sun mesh and band mesh, the energy loss at the band mesh will be roughly 13 times higher than the power loss at the sun mesh.