precision planetary gearbox

Precision Planetary Gearheads
The primary reason to use a gearhead is that it creates it possible to control a big load inertia with a comparatively small motor inertia. Without the gearhead, acceleration or velocity control of the load would require that the engine torque, and thus current, would need to be as many times better as the decrease ratio which can be used. Moog offers an array of windings in each frame size that, combined with an array of reduction ratios, provides an range of solution to result requirements. Each combination of electric motor and gearhead offers different advantages.
Precision Planetary Gearheads
gearheads
32 mm Low Cost Planetary Gearhead
32 mm Precision Planetary Gearhead
52 mm Accuracy Planetary Gearhead
62 mm Accuracy Planetary Gearhead
81 mm Accuracy Planetary Gearhead
120 mm Precision Planetary Gearhead
Precision planetary gearhead.
Series P high precision inline planetary servo drive will fulfill your most demanding automation applications. The compact design, universal housing with precision bearings and precision planetary gearing provides substantial torque density and will be offering high positioning performance. Series P offers exact ratios from 3:1 through 40:1 with the precision planetary gearbox highest efficiency and lowest backlash in the industry.
Key Features
Sizes: 60, 90, 115, 140, 180 and 220
Output Torque: Up to at least one 1,500 Nm (13,275 lb.in.)
Gear Ratios: Up to 100:1 in two stages
Input Options: Meets any servo motor
Output Options: Outcome with or without keyway
Product Features
Because of the load sharing attributes of multiple tooth contacts,planetary gearboxes supply the highest torque and stiffness for any given envelope
Balanced planetary kinematics at high speeds combined with associated load sharing produce planetary-type gearheads perfect for servo applications
Accurate helical technology provides increased tooth to tooth contact ratio by 33% vs. spur gearing 12¡ helix angle produces soft and quiet operation
One piece world carrier and output shaft design reduces backlash
Single step machining process
Assures 100% concentricity Improves torsional rigidity
Efficient lubrication forever
The excessive precision PS-series inline helical planetary gearheads are available in 60-220mm frame sizes and offer high torque, excessive radial loads, low backlash, substantial input speeds and a little package size. Custom variations are possible
Print Product Overview
Ever-Power PS-series gearheads supply the highest efficiency to meet up your applications torque, inertia, speed and precision requirements. Helical gears present smooth and quiet procedure and create higher vitality density while maintaining a little envelope size. Available in multiple body sizes and ratios to meet up a variety of application requirements.
Markets
• Industrial automation
• Semiconductor and electronics
• Food and beverage
• Health and beauty
• Life science
• Robotics
• Military
Features and Benefits
• Helical gears provide even more torque capability, lower backlash, and noiseless operation
• Ring gear cut into housing provides better torsional stiffness
• Widely spaced angular speak to bearings provide output shaft with large radial and axial load capability
• Plasma nitride heat treatment for gears for remarkable surface have on and shear strength
• Sealed to IP65 to safeguard against harsh environments
• Mounting packages for direct and convenient assembly to hundreds of different motors
Applications
• Packaging
• Processing
• Bottling
• Milling
• Antenna pedestals
• Conveyors
• Robotic actuation and propulsion
PERFORMANCE CHARACTERISTICS
PERFORMANCEHigh Precision
CONFIGURATIONInline
GEAR GEOMETRYHelical Planetary
FRAME SIZE60mm | 90mm | 115mm | 142mm | 180mm | 220mm
STANDARD BACKLASH (ARC-MIN)< 4 to < 8
LOW BACKLASH (ARC-MIN)< 3 to < 6
NOMINAL TORQUE (NM)27 – …1808
NOMINAL TORQUE (IN-LBS)240 – 16091
RADIAL LOAD (N)1650 – 38000
RADIAL LOAD (LBS)370 – 8636
RATIO3, 4, 5, 7, 10, 15, 20, 25, 30, 40, 50, 70, 100:1
MAXIMUM INPUT Rate (RPM)6000
AMOUNT OF PROTECTION (IP)IP65
EFFICIENCY For NOMINAL TORQUE (%)94 – 97
CUSTOM VERSIONS AVAILABLEYes
The Planetary (Epicyclical) Gear System as the “System of preference” for Servo Gearheads
Recurrent misconceptions regarding planetary gears systems involve backlash: Planetary systems are being used for servo gearheads due to their inherent low backlash; low backlash is normally the main characteristic requirement of a servo gearboxes; backlash is a way of measuring the accuracy of the planetary gearbox.
The truth is, fixed-axis, standard, “spur” gear arrangement systems could be designed and designed merely as easily for low backlash requirements. Furthermore, low backlash isn’t an absolute requirement for servo-established automation applications. A moderately low backlash is a good idea (in applications with very high start/stop, forward/reverse cycles) in order to avoid internal shock loads in the gear mesh. Having said that, with today’s high-resolution motor-feedback equipment and associated movement controllers it is easy to compensate for backlash anytime you will find a adjust in the rotation or torque-load direction.
If, for as soon as, we discount backlash, after that what are the causes for selecting a even more expensive, seemingly more complex planetary devices for servo gearheads? What advantages do planetary gears provide?
High Torque Density: Compact Design
An important requirement for automation applications is substantial torque capacity in a compact and light package. This substantial torque density requirement (a higher torque/volume or torque/weight ratio) is important for automation applications with changing great dynamic loads in order to avoid additional system inertia.
Depending upon the amount of planets, planetary systems distribute the transferred torque through multiple gear mesh points. This implies a planetary equipment with declare three planets can transfer 3 x the torque of a similar sized fixed axis “normal” spur gear system
Rotational Stiffness/Elasticity
Excessive rotational (torsional) stiffness, or minimized elastic windup, is very important to applications with elevated positioning accuracy and repeatability requirements; especially under fluctuating loading circumstances. The strain distribution unto multiple equipment mesh points signifies that the load is reinforced by N contacts (where N = amount of planet gears) hence raising the torsional stiffness of the gearbox by aspect N. This means it noticeably lowers the lost action compared to a similar size standard gearbox; which is what’s desired.
Low Inertia
Added inertia results in an extra torque/energy requirement of both acceleration and deceleration. The smaller gears in planetary program lead to lower inertia. Compared to a same torque ranking standard gearbox, it is a good approximation to state that the planetary gearbox inertia is normally smaller by the sq . of the amount of planets. Again, this advantage is certainly rooted in the distribution or “branching” of the strain into multiple equipment mesh locations.
High Speeds
Modern servomotors run at high rpm’s, hence a servo gearbox should be able to operate in a reliable manner at high insight speeds. For servomotors, 3,000 rpm is virtually the standard, and in fact speeds are frequently increasing in order to optimize, increasingly complicated application requirements. Servomotors operating at speeds in excess of 10,000 rpm aren’t unusual. From a score perspective, with increased rate the power density of the engine increases proportionally with no real size enhance of the engine or electronic drive. Thus, the amp rating stays about the same while only the voltage must be increased. A significant factor is with regards to the lubrication at high operating speeds. Set axis spur gears will exhibit lubrication “starvation” and quickly fail if jogging at high speeds for the reason that lubricant is usually slung away. Only unique means such as costly pressurized forced lubrication systems can solve this issue. Grease lubrication is normally impractical as a result of its “tunneling effect,” in which the grease, over time, is pushed away and cannot movement back into the mesh.
In planetary systems the lubricant cannot escape. It is constantly redistributed, “pushed and pulled” or “mixed” into the gear contacts, ensuring safe lubrication practically in virtually any mounting posture and at any velocity. Furthermore, planetary gearboxes can be grease lubricated. This characteristic is usually inherent in planetary gearing due to the relative motion between the several gears making up the arrangement.
THE VERY BEST ‘Balanced’ Planetary Ratio from a Torque Density Point of View
For simpler computation, it is preferred that the planetary gearbox ratio can be an exact integer (3, 4, 6…). Since we are very much accustomed to the decimal system, we have a tendency to use 10:1 despite the fact that it has no practical advantages for the computer/servo/motion controller. Truly, as we will have, 10:1 or more ratios will be the weakest, using the least “balanced” size gears, and therefore have the cheapest torque rating.
This article addresses simple planetary gear arrangements, meaning all gears are engaging in the same plane. The vast majority of the epicyclical gears found in servo applications happen to be of the simple planetary design. Physique 2a illustrates a cross-section of this kind of a planetary gear arrangement with its central sun gear, multiple planets (3), and the ring gear. The definition of the ratio of a planetary gearbox shown in the physique is obtained immediately from the unique kinematics of the system. It is obvious that a 2:1 ratio is not possible in a simple planetary gear system, since to satisfy the prior equation for a ratio of 2:1, the sun gear would have to possess the same diameter as the ring gear. Figure 2b shows sunlight gear size for distinct ratios. With increased ratio sunlight gear size (size) is decreasing.
Since gear size impacts loadability, the ratio is a strong and direct influence to the torque rating. Figure 3a displays the gears in a 3:1, 4:1, and 10:1 straightforward system. At 3:1 ratio, the sun gear is huge and the planets happen to be small. The planets have become “thin walled”, limiting the space for the earth bearings and carrier pins, therefore limiting the loadability. The 4:1 ratio is definitely a well-balanced ratio, with sunlight and planets getting the same size. 5:1 and 6:1 ratios still yield rather good balanced equipment sizes between planets and sunshine. With bigger ratios approaching 10:1, the tiny sun gear becomes a strong limiting aspect for the transferable torque. Simple planetary patterns with 10:1 ratios have really small sun gears, which sharply limitations torque rating.
How Positioning Accuracy and Repeatability is Suffering from the Precision and Quality School of the Servo Gearhead
As previously mentioned, this is a general misconception that the backlash of a gearbox is a measure of the quality or precision. The fact is that the backlash features practically nothing to perform with the product quality or accuracy of a gear. Simply the consistency of the backlash can be considered, up to certain degree, a form of way of measuring gear top quality. From the application point of view the relevant problem is, “What gear real estate are influencing the accuracy of the motion?”
Positioning precision is a way of measuring how specific a desired position is reached. In a shut loop system the primary determining/influencing elements of the positioning reliability will be the accuracy and quality of the feedback product and where the position is certainly measured. If the positioning is definitely measured at the final outcome of the actuator, the influence of the mechanical parts could be practically eliminated. (Direct position measurement can be used mainly in very high precision applications such as for example machine equipment). In applications with a lesser positioning accuracy necessity, the feedback transmission is made by a feedback devise (resolver, encoder) in the electric motor. In this case auxiliary mechanical components attached to the motor such as a gearbox, couplings, pulleys, belts, etc. will impact the positioning accuracy.
We manufacture and design high-quality gears and complete speed-reduction systems. For build-to-print custom parts, assemblies, design, engineering and manufacturing companies get in touch with our engineering group.
Speed reducers and gear trains can be classified according to equipment type as well as relative position of suggestions and result shafts. SDP/SI offers a wide variety of standard catalog items:
gearheads and speed reducers
planetary and spur gearheads
proper angle and dual productivity right angle planetary gearheads
We realize you might not exactly be interested in choosing the ready-to-use speed reducer. For anybody who want to design your unique special gear teach or acceleration reducer we give you a broad range of accuracy gears, types, sizes and materials, available from stock.