precision planetary gearbox

precision planetary gearbox Precision Planetary Gearheads
The primary reason to use a gearhead is that it makes it possible to control a huge load inertia with a comparatively small motor inertia. Without the gearhead, acceleration or velocity control of the strain would require that the engine torque, and thus current, would have to be as many times greater as the reduction ratio which can be used. Moog offers an array of windings in each body size that, combined with an array of reduction ratios, provides an range of solution to output requirements. Each combination of electric motor and gearhead offers one of a kind advantages.
Precision Planetary Gearheads
gearheads
32 mm LOW PRICED Planetary Gearhead
32 mm Accuracy Planetary Gearhead
52 mm Precision Planetary Gearhead
62 mm Precision Planetary Gearhead
81 mm Accuracy Planetary Gearhead
120 mm Precision Planetary Gearhead
Precision planetary gearhead.
Series P high precision inline planetary servo travel will satisfy your most demanding automation applications. The compact design, universal housing with precision bearings and precision planetary gearing provides huge torque density and will be offering high positioning performance. Series P offers specific ratios from 3:1 through 40:1 with the best efficiency and lowest backlash in the market.
Key Features
Sizes: 60, 90, 115, 140, 180 and 220
Output Torque: Up to at least one 1,500 Nm (13,275 lb.in.)
Equipment Ratios: Up to 100:1 in two stages
Input Options: Suits any servo motor
Output Options: Output with or without keyway
Product Features
Due to the load sharing features of multiple tooth contacts,planetary gearboxes provide the highest torque and stiffness for any given envelope
Balanced planetary kinematics for high speeds combined with the associated load sharing produce planetary-type gearheads well suited for servo applications
Authentic helical technology provides elevated tooth to tooth contact ratio by 33% versus. spur gearing 12¡ helix angle produces easy and quiet operation
One piece world carrier and outcome shaft design reduces backlash
Single step machining process
Assures 100% concentricity Enhances torsional rigidity
Efficient lubrication forever
The huge precision PS-series inline helical planetary gearheads can be found in 60-220mm frame sizes and provide high torque, high radial loads, low backlash, substantial input speeds and a tiny package size. Custom editions are possible
Print Product Overview
Ever-Power PS-series gearheads supply the highest performance to meet your applications torque, inertia, speed and precision requirements. Helical gears offer smooth and quiet operation and create higher power density while retaining a small envelope size. Obtainable in multiple body sizes and ratios to meet up a number 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 more torque ability, lower backlash, and silent operation
• Ring gear lower into housing provides increased torsional stiffness
• Widely spaced angular speak to bearings provide end result shaft with large radial and axial load capability
• Plasma nitride heat treatment for gears for good surface put on and shear strength
• Sealed to IP65 to protect 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
Framework 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 SPEED (RPM)6000
AMOUNT OF PROTECTION (IP)IP65
EFFICIENCY In NOMINAL TORQUE (%)94 – 97
CUSTOM VERSIONS AVAILABLEYes
The Planetary (Epicyclical) Gear System as the “Program of preference” for Servo Gearheads
Regular misconceptions regarding planetary gears systems involve backlash: Planetary systems are used for servo gearheads due to their inherent low backlash; low backlash is the main characteristic requirement for a servo gearboxes; backlash can be a measure of the precision of the planetary gearbox.
The fact is, fixed-axis, standard, “spur” gear arrangement systems could be designed and created only as easily for low backlash requirements. Furthermore, low backlash is not an absolute requirement of servo-established automation applications. A moderately low backlash is a good idea (in applications with high start/stop, ahead/reverse cycles) to avoid interior shock loads in the apparatus mesh. Having said that, with today’s high-resolution motor-feedback products and associated action controllers it is simple to compensate for backlash anytime there exists a adjust in the rotation or torque-load direction.
If, for as soon as, we discount backlash, then what are the causes for selecting a more expensive, seemingly more technical planetary devices for servo gearheads? What positive aspects do planetary gears give?
High Torque Density: Compact Design
An important requirement for automation applications is substantial torque capability in a compact and light package. This excessive torque density requirement (a higher torque/quantity or torque/pounds ratio) is important for automation applications with changing large dynamic loads in order to avoid additional system inertia.
Depending upon the quantity of planets, planetary devices distribute the transferred torque through multiple equipment mesh points. This implies a planetary equipment with claim three planets can transfer 3 x the torque of an identical sized fixed axis “common” spur gear system
Rotational Stiffness/Elasticity
Great rotational (torsional) stiffness, or minimized elastic windup, is important for applications with elevated positioning accuracy and repeatability requirements; especially under fluctuating loading circumstances. The strain distribution unto multiple gear mesh points ensures that the load is supported by N contacts (where N = quantity of planet gears) hence increasing the torsional stiffness of the gearbox by point N. This means it significantly lowers the lost movement compared to an identical size standard gearbox; which is what is desired.
Low Inertia
Added inertia results within an more torque/energy requirement for both acceleration and deceleration. Small gears in planetary system bring about lower inertia. In comparison to a same torque score standard gearbox, this is a fair approximation to state that the planetary gearbox inertia can be smaller by the square of the number of planets. Once again, this advantage is normally rooted in the distribution or “branching” of the load into multiple gear mesh locations.
High Speeds
Modern servomotors run at great rpm’s, hence a servo gearbox should be in a position to operate in a trusted manner at high type speeds. For servomotors, 3,000 rpm is virtually the standard, and actually speeds are frequently increasing in order to optimize, increasingly intricate application requirements. Servomotors working at speeds more than 10,000 rpm aren’t unusual. From a score perspective, with increased speed the energy density of the motor increases proportionally without any real size maximize of the engine or electronic drive. Thus, the amp rating remains a comparable while simply the voltage must be increased. A significant factor is with regards to the lubrication at excessive operating speeds. Set axis spur gears will exhibit lubrication “starvation” and quickly fail if running at high speeds because the lubricant is definitely slung away. Only specialized means such as costly pressurized forced lubrication devices can solve this problem. Grease lubrication is certainly impractical because of its “tunneling effect,” where the grease, as time passes, is pushed aside and cannot move back to the mesh.
In planetary systems the lubricant cannot escape. It is continuously redistributed, “pushed and pulled” or “mixed” into the gear contacts, ensuring safe lubrication practically in virtually any mounting job and at any quickness. Furthermore, planetary gearboxes can be grease lubricated. This feature is definitely inherent in planetary gearing as a result of the relative movement between the different gears making up the arrangement.
The Best ‘Balanced’ Planetary Ratio from a Torque Density Point of View
For much easier computation, it is desired that the planetary gearbox ratio can be an exact integer (3, 4, 6…). Since we are so used to the decimal system, we tend to use 10:1 even though it has no practical advantages for the pc/servo/motion controller. In fact, as we will have, 10:1 or more ratios will be the weakest, using the least “balanced” size gears, and therefore have the lowest torque rating.
This article addresses simple planetary gear arrangements, meaning all gears are participating in the same plane. Almost all the epicyclical gears used in servo applications are of the simple planetary design. Determine 2a illustrates a cross-section of such a planetary gear set up with its central sun gear, multiple planets (3), and the ring gear. The definition of the ratio of a planetary gearbox shown in the body is obtained straight from the unique kinematics of the machine. It is obvious a 2:1 ratio is not possible in a straightforward planetary gear system, since to satisfy the prior equation for a ratio of 2:1, sunlight gear would need to have the same diameter as the ring equipment. Figure 2b shows the sun gear size for diverse ratios. With an increase of ratio the sun gear size (size) is decreasing.
Since gear size influences loadability, the ratio is a solid and direct affect to the torque score. Figure 3a shows the gears in a 3:1, 4:1, and 10:1 basic system. At 3:1 ratio, sunlight gear is significant and the planets happen to be small. The planets have become “slim walled”, limiting the area for the planet bearings and carrier pins, therefore limiting the loadability. The 4:1 ratio is normally a well-well-balanced ratio, with sunlight and planets having the same size. 5:1 and 6:1 ratios still yield pretty good balanced gear sizes between planets and sun. With larger ratios approaching 10:1, the small sun equipment becomes a strong limiting issue for the transferable torque. Simple planetary patterns with 10:1 ratios have really small sun gears, which sharply limits torque rating.
How Positioning Precision and Repeatability is Affected by the Precision and Top quality Category of the Servo Gearhead
As previously mentioned, this is a general misconception that the backlash of a gearbox is a way of measuring the quality or precision. The fact is that the backlash features practically nothing to do with the 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 quality. From the application viewpoint the relevant concern is, “What gear houses are influencing the precision of the motion?”
Positioning precision is a measure of how exact a desired situation is reached. In a closed loop system the prime determining/influencing factors of the positioning precision will be the accuracy and image resolution of the feedback system and where the job is certainly measured. If the positioning is normally measured at the final end result of the actuator, the affect of the mechanical elements could be practically eliminated. (Direct position measurement is used mainly in high accuracy applications such as machine equipment). In applications with less positioning accuracy requirement, the feedback transmission is produced by a opinions devise (resolver, encoder) in the engine. In this instance auxiliary mechanical components mounted on the motor such as a gearbox, couplings, pulleys, belts, etc. will impact the positioning accuracy.
We manufacture and design high-quality gears as well as complete speed-reduction systems. For build-to-print custom parts, assemblies, style, engineering and manufacturing companies speak to our engineering group.
Speed reducers and equipment trains can be classified according to gear type and also relative position of source and end result shafts. SDP/SI offers a multitude of standard catalog items:
gearheads and speed reducers
planetary and spur gearheads
proper angle and dual end result right angle planetary gearheads
We realize you may well not be interested in choosing the ready-to-use swiftness reducer. For those of you who want to design your personal special gear train or swiftness reducer we give a broad range of precision gears, types, sizes and materials, available from stock.