Precision Planetary Gearheads
The primary reason to employ a gearhead is that it makes it possible to control a big 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 so current, would have to be as much times increased as the lowering ratio which can be used. Moog offers a selection of windings in each framework size that, coupled with an array of reduction ratios, provides an assortment of solution to result requirements. Each combo of electric motor and gearhead offers one of a kind advantages.
Precision Planetary Gearheads
32 mm LOW PRICED Planetary Gearhead
32 mm Accuracy Planetary Gearhead
52 mm Precision 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 meet your most demanding automation applications. The compact design, universal housing with precision bearings and accuracy planetary gearing provides great torque density while offering high positioning overall performance. Series P offers specific ratios from 3:1 through 40:1 with the highest efficiency and lowest backlash in the industry.
Sizes: 60, 90, 115, 140, 180 and 220
Productivity Torque: Up to 1 1,500 Nm (13,275 lb.in.)
Equipment Ratios: Up to 100:1 in two stages
Input Options: Meets any servo motor
Output Options: End result with or without keyway
Because of the load sharing features of multiple tooth contacts,planetary gearboxes supply the highest torque and stiffness for any given envelope
Balanced planetary kinematics for high speeds combined with associated load sharing produce planetary-type gearheads well suited for servo applications
Accurate helical technology provides increased tooth to tooth contact ratio by 33% versus. spur gearing 12¡ helix angle produces even and quiet operation
One piece planet carrier and outcome shaft design reduces backlash
Single step machining process
Assures 100% concentricity Increases torsional rigidity
Efficient lubrication forever
The large precision PS-series inline helical planetary gearheads can be found in 60-220mm frame sizes and provide high torque, excessive radial loads, low backlash, substantial input speeds and a little package size. Custom editions are possible
Print Product Overview
Ever-Power PS-series gearheads supply the highest performance to meet up your applications torque, inertia, speed and reliability requirements. Helical gears provide smooth and quiet operation and create higher electrical power density while preserving a little envelope size. Available in multiple frame sizes and ratios to meet various application requirements.
• Industrial automation
• Semiconductor and electronics
• Food and beverage
• Health and beauty
• Life science
Features and Benefits
• Helical gears provide more torque capacity, lower backlash, and silent operation
• Ring gear trim into housing provides increased torsional stiffness
• Widely spaced angular contact bearings provide end result shaft with large radial and axial load capability
• Plasma nitride heat therapy for gears for remarkable surface don and shear precision planetary gearbox strength
• Sealed to IP65 to safeguard against harsh environments
• Mounting products for direct and convenient assembly to hundreds of different motors
• Antenna pedestals
• Robotic actuation and propulsion
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
Consistent misconceptions regarding planetary gears systems involve backlash: Planetary systems are being used for servo gearheads because of their inherent low backlash; low backlash is certainly the main characteristic requirement for a servo gearboxes; backlash is normally a way of measuring the accuracy of the planetary gearbox.
The fact is, fixed-axis, standard, “spur” gear arrangement systems could be designed and designed 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 very high start/stop, onward/reverse cycles) to avoid inner shock loads in the apparatus mesh. That said, with today’s high-image resolution motor-feedback gadgets 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, then what are the causes for selecting a more expensive, seemingly more technical planetary systems for servo gearheads? What advantages do planetary gears provide?
High Torque Density: Small Design
An important requirement of automation applications is huge torque capability in a compact and light bundle. This great torque density requirement (a higher torque/volume or torque/excess weight ratio) is very important to automation applications with changing large dynamic loads to avoid additional system inertia.
Depending upon the amount of planets, planetary systems distribute the transferred torque through multiple equipment mesh points. This means a planetary gear with say three planets can transfer three times the torque of an identical sized fixed axis “normal” spur gear system
Huge rotational (torsional) stiffness, or minimized elastic windup, is important for applications with elevated positioning accuracy and repeatability requirements; specifically under fluctuating loading circumstances. The strain distribution unto multiple gear mesh points means that the load is reinforced by N contacts (where N = quantity of planet gears) consequently raising the torsional stiffness of the gearbox by element N. This implies it noticeably lowers the lost movement compared to an identical size standard gearbox; and this is what is desired.
Added inertia results in an more torque/energy requirement for both acceleration and deceleration. Small gears in planetary program result in lower inertia. In comparison to a same torque ranking standard gearbox, it is a good approximation to say that the planetary gearbox inertia is certainly smaller by the sq . of the number of planets. Once again, this advantage is rooted in the distribution or “branching” of the strain into multiple gear mesh locations.
Modern servomotors run at great rpm’s, hence a servo gearbox must be in a position to operate in a reliable manner at high insight speeds. For servomotors, 3,000 rpm is pretty much the standard, and actually speeds are constantly increasing as a way to optimize, increasingly complicated application requirements. Servomotors working at speeds in excess of 10,000 rpm aren’t unusual. From a ranking perspective, with increased velocity the energy density of the engine increases proportionally without the real size enhance of the motor or electronic drive. Therefore, the amp rating stays about the same while just the voltage should be increased. An important factor is in regards to the lubrication at great operating speeds. Fixed axis spur gears will exhibit lubrication “starvation” and quickly fail if running at high speeds since the lubricant is definitely slung away. Only particular means such as costly pressurized forced lubrication devices can solve this problem. Grease lubrication is normally impractical due to its “tunneling effect,” in which the grease, over time, is pushed apart and cannot circulation back into the mesh.
In planetary systems the lubricant cannot escape. It really is continually redistributed, “pushed and pulled” or “mixed” into the gear contacts, ensuring secure lubrication practically in virtually any mounting location and at any acceleration. Furthermore, planetary gearboxes could be grease lubricated. This feature is certainly inherent in planetary gearing due to the relative action between the different gears creating the arrangement.
The Best ‘Balanced’ Planetary Ratio from a Torque Density Perspective
For simpler computation, it is desired that the planetary gearbox ratio is an actual integer (3, 4, 6…). Since we are so used to the decimal program, we have a tendency to use 10:1 despite the fact that it has no practical benefit for the pc/servo/motion controller. Basically, as we will have, 10:1 or more ratios are the weakest, using the least “well-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 happen to be of the simple planetary design. Physique 2a illustrates a cross-section of this kind of a planetary gear arrangement using its central sun gear, multiple planets (3), and the ring gear. The definition of the ratio of a planetary gearbox proven in the shape is obtained straight from the unique kinematics of the machine. It is obvious that a 2:1 ratio is not possible in a simple planetary gear program, since to satisfy the previous equation for a ratio of 2:1, sunlight gear would have to possess the same diameter as the ring equipment. Figure 2b shows sunlight gear size for distinct ratios. With an increase of ratio sunlight gear size (size) is decreasing.
Since gear size impacts loadability, the ratio is a strong and direct impact to the torque score. Figure 3a reveals the gears in a 3:1, 4:1, and 10:1 simple system. At 3:1 ratio, sunlight gear is large and the planets happen to be small. The planets are becoming “slim walled”, limiting the area for the earth bearings and carrier pins, therefore limiting the loadability. The 4:1 ratio is definitely a well-well-balanced ratio, with sunlight and planets having the same size. 5:1 and 6:1 ratios still yield quite good balanced equipment sizes between planets and sun. With higher ratios approaching 10:1, the small sun equipment becomes a solid limiting factor for the transferable torque. Simple planetary designs with 10:1 ratios have very small sunshine gears, which sharply limits torque rating.
How Positioning Reliability and Repeatability is Affected by the Precision and Top quality Category of the Servo Gearhead
As previously mentioned, it is a general misconception that the backlash of a gearbox is a measure of the quality or precision. The truth is that the backlash features practically nothing to carry out with the product quality or accuracy of a gear. Just the consistency of the backlash can be viewed as, up to certain degree, a form of way of measuring gear quality. From the application viewpoint the relevant concern is, “What gear homes are influencing the accuracy of the motion?”
Positioning accuracy is a way of measuring how precise a desired job is reached. In a shut loop system the primary determining/influencing factors of the positioning reliability will be the accuracy and image resolution of the feedback device and where the job is certainly measured. If the positioning is usually measured at the ultimate result of the actuator, the effect of the mechanical pieces can be practically eliminated. (Immediate position measurement is utilized mainly in high precision applications such as for example machine equipment). In applications with less positioning accuracy requirement, the feedback transmission is produced by a responses devise (resolver, encoder) in the motor. In this instance auxiliary mechanical components attached to the motor like a gearbox, couplings, pulleys, belts, etc. will effect the positioning accuracy.
We manufacture and style high-quality gears and also complete speed-reduction systems. For build-to-print customized parts, assemblies, style, engineering and manufacturing companies contact our engineering group.
Speed reducers and gear trains can be categorized according to gear type in addition to relative position of suggestions and result shafts. SDP/SI offers a multitude of standard catalog items:
gearheads and speed reducers
planetary and spur gearheads
right angle and dual output right angle planetary gearheads
We realize you may not be interested in selecting a ready-to-use quickness reducer. For anybody who want to design your very own special gear educate or swiftness reducer we give a broad range of precision gears, types, sizes and material, available from stock.
Precision Planetary Gearheads