Precision Planetary Gearheads
The primary reason to employ a gearhead is that it makes it possible to regulate a big load inertia with a comparatively small motor inertia. Without the gearhead, acceleration or velocity control of the strain would require that the motor torque, and so current, would need to be as much times greater as the lowering ratio which is used. Moog offers an array of windings in each frame size that, combined with a selection of reduction ratios, offers an range of solution to output requirements. Each combination of 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 fulfill your most demanding automation applications. The compact style, universal housing with accuracy bearings and accuracy planetary gearing provides huge torque density and will be offering high positioning functionality. Series P offers actual 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
Outcome 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: Outcome 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 at high speeds combined with associated load sharing make planetary-type gearheads ideal for servo applications
The case helical technology provides increased tooth to tooth contact ratio by 33% vs. spur gearing 12¡ helix angle produces even 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 for life
The substantial precision PS-series inline helical planetary gearheads can be found in 60-220mm frame sizes and offer high torque, excessive radial loads, low backlash, large input speeds and a little package size. Custom variants are possible
Print Product Overview
Ever-Power PS-series gearheads provide the highest effectiveness to meet up your applications torque, inertia, speed and reliability requirements. Helical gears provide smooth and quiet operation and create precision planetary gearbox higher electricity density while maintaining a little envelope size. Obtainable in multiple framework 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 more torque ability, lower backlash, and peaceful operation
• Ring gear lower into housing provides greater torsional stiffness
• Widely spaced angular speak to bearings provide result shaft with excessive radial and axial load capability
• Plasma nitride heat treatment for gears for exceptional surface don and shear strength
• Sealed to IP65 to safeguard against harsh environments
• Mounting products for direct and easy 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 Velocity (RPM)6000
DEGREE OF PROTECTION (IP)IP65
EFFICIENCY AT NOMINAL TORQUE (%)94 – 97
CUSTOM VERSIONS AVAILABLEYes
The Planetary (Epicyclical) Gear System as the “Program of Choice” for Servo Gearheads
Repeated misconceptions regarding planetary gears systems involve backlash: Planetary systems are used for servo gearheads as a result of their inherent low backlash; low backlash is the main characteristic requirement for a servo gearboxes; backlash is usually a measure of the accuracy of the planetary gearbox.
The fact is, fixed-axis, standard, “spur” gear arrangement systems could be designed and developed simply as easily for low backlash requirements. Furthermore, low backlash is not an absolute requirement of servo-structured automation applications. A moderately low backlash is advisable (in applications with very high start/stop, frontward/reverse cycles) to avoid internal shock loads in the gear mesh. Having said that, with today’s high-resolution motor-feedback equipment and associated action controllers it is easy to compensate for backlash anytime you will find a modify in the rotation or torque-load direction.
If, for as soon as, we discount backlash, then what are the factors for selecting a more expensive, seemingly more complex planetary systems for servo gearheads? What advantages do planetary gears present?
High Torque Density: Small Design
An important requirement for automation applications is great torque capacity in a concise and light package. This high torque density requirement (a high torque/quantity or torque/fat ratio) is very important to automation applications with changing large dynamic loads in order to avoid additional system inertia.
Depending upon the amount of planets, planetary devices distribute the transferred torque through multiple gear mesh points. This implies a planetary gear with declare three planets can transfer 3 x the torque of a similar sized fixed axis “common” 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; specifically under fluctuating loading conditions. The load distribution unto multiple gear mesh points signifies that the load is supported by N contacts (where N = number of planet gears) therefore raising the torsional stiffness of the gearbox by component N. This means it noticeably lowers the lost motion compared to a similar size standard gearbox; which is what is desired.
Low Inertia
Added inertia results in an more torque/energy requirement for both acceleration and deceleration. The smaller gears in planetary program cause lower inertia. Compared to a same torque ranking standard gearbox, it is a fair approximation to state that the planetary gearbox inertia is smaller by the square of the amount of planets. Again, this advantage can be rooted in the distribution or “branching” of the load into multiple gear mesh locations.
High Speeds
Modern day servomotors run at substantial rpm’s, hence a servo gearbox should be able to operate in a trusted manner at high type speeds. For servomotors, 3,000 rpm is practically the standard, and actually speeds are constantly increasing so that you can optimize, increasingly sophisticated application requirements. Servomotors running at speeds in excess of 10,000 rpm aren’t unusual. From a rating viewpoint, with increased speed the power density of the engine increases proportionally without the real size increase of the engine or electronic drive. Thus, the amp rating stays about the same while only the voltage should be increased. A significant factor is with regards to the lubrication at great operating speeds. Set axis spur gears will exhibit lubrication “starvation” and quickly fail if operating at high speeds as the lubricant can be 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,” where the grease, over time, is pushed aside and cannot circulation back into the mesh.
In planetary systems the lubricant cannot escape. It really is consistently redistributed, “pushed and pulled” or “mixed” into the equipment contacts, ensuring secure lubrication practically in any mounting job and at any acceleration. Furthermore, planetary gearboxes could be grease lubricated. This feature is definitely inherent in planetary gearing as a result of the relative motion between the various gears creating the arrangement.
The Best ‘Balanced’ Planetary Ratio from a Torque Density Viewpoint
For simpler computation, it is desired that the planetary gearbox ratio is an specific integer (3, 4, 6…). Since we are very much accustomed to the decimal program, we tend to use 10:1 despite the fact that this has no practical gain for the computer/servo/motion controller. In fact, as we will see, 10:1 or higher ratios will be the weakest, using the least “balanced” size gears, and hence 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. Figure 2a illustrates a cross-section of this kind of a planetary gear set up with its central sun equipment, multiple planets (3), and the ring gear. This is of the ratio of a planetary gearbox displayed in the body is obtained immediately from the initial kinematics of the machine. It is obvious a 2:1 ratio is not possible in a straightforward 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 the sun gear size for distinct ratios. With increased ratio sunlight gear diameter (size) is decreasing.
Since gear size affects loadability, the ratio is a solid and direct influence to the torque rating. Figure 3a reveals the gears in a 3:1, 4:1, and 10:1 straightforward system. At 3:1 ratio, sunlight gear is significant and the planets are small. The planets are becoming “slim walled”, limiting the space for the earth bearings and carrier pins, hence limiting the loadability. The 4:1 ratio can be a well-well-balanced ratio, with sun and planets getting the same size. 5:1 and 6:1 ratios still yield rather good balanced equipment sizes between planets and sun. With higher ratios approaching 10:1, the tiny sun gear becomes a strong limiting component for the transferable torque. Simple planetary styles 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 Class of the Servo Gearhead
As previously mentioned, this is a general misconception that the backlash of a gearbox is a measure of the product quality or precision. The fact is that the backlash offers practically nothing to carry out with the product quality or accuracy of a gear. Only the consistency of the backlash can be considered, up to certain degree, a form of measure of gear quality. From the application viewpoint the relevant question is, “What gear real estate are influencing the precision of the motion?”
Positioning reliability is a measure of how exact a desired placement is reached. In a closed loop system the primary determining/influencing factors of the positioning reliability are the accuracy and quality of the feedback device and where the situation is definitely measured. If the position is definitely measured at the ultimate result of the actuator, the impact of the mechanical components could be practically eliminated. (Direct position measurement can be used mainly in high precision applications such as for example machine tools). In applications with less positioning accuracy requirement, the feedback transmission is generated by a feedback devise (resolver, encoder) in the motor. In this instance auxiliary mechanical components attached to the motor for instance a gearbox, couplings, pulleys, belts, etc. will impact the positioning accuracy.
We manufacture and style high-quality gears together with complete speed-reduction devices. For build-to-print custom parts, assemblies, design, engineering and manufacturing providers speak to our engineering group.
Speed reducers and equipment trains can be categorized according to gear type as well as relative position of type and productivity shafts. SDP/SI offers a wide variety of standard catalog items:
gearheads and speed reducers
planetary and spur gearheads
proper angle and dual output right angle planetary gearheads
We realize you might not exactly be interested in choosing the ready-to-use rate reducer. For anybody who want to design your individual special gear educate or velocity reducer we offer a broad range of precision gears, types, sizes and materials, available from stock.