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 load would require that the engine torque, and therefore current, would have to be as many times greater as the reduction ratio which can be used. Moog offers a selection of windings in each body size that, combined with a selection of reduction ratios, offers an assortment of solution to outcome requirements. Each mixture of electric motor and gearhead offers exceptional advantages.
Precision Planetary Gearheads
gearheads
32 mm Low Cost Planetary Gearhead
32 mm Precision Planetary Gearhead
52 mm Accuracy Planetary Gearhead
62 mm Precision Planetary Gearhead
81 mm Precision Planetary Gearhead
120 mm Accuracy Planetary Gearhead
Precision planetary gearhead.
Series P high accuracy inline planetary servo drive will fulfill your most demanding automation applications. The compact design, universal housing with accuracy bearings and precision planetary gearing provides huge torque precision planetary gearbox density while offering high positioning overall performance. Series P offers exact ratios from 3:1 through 40:1 with the highest efficiency and lowest backlash in the industry.
Key Features
Sizes: 60, 90, 115, 140, 180 and 220
Outcome Torque: Up to 1 1,500 Nm (13,275 lb.in.)
Gear Ratios: Up to 100:1 in two stages
Input Options: Suits any servo motor
Output Options: Outcome with or without keyway
Product Features
Because of the load sharing attributes of multiple tooth contacts,planetary gearboxes provide the highest torque and stiffness for just about any given envelope
Balanced planetary kinematics at high speeds combined with associated load sharing make planetary-type gearheads ideal for servo applications
Authentic helical technology provides elevated tooth to tooth contact ratio by 33% versus. spur gearing 12¡ helix angle produces smooth and quiet operation
One piece planet carrier and result 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 purchased in 60-220mm frame sizes and offer high torque, high radial loads, low backlash, huge input speeds and a little package size. Custom editions are possible
Print Product Overview
Ever-Power PS-series gearheads supply the highest functionality to meet up your applications torque, inertia, speed and precision requirements. Helical gears offer smooth and quiet operation and create higher power density while keeping a small envelope size. Obtainable in multiple framework sizes and ratios to meet up many different 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 capability, lower backlash, and silent operation
• Ring gear trim into housing provides better torsional stiffness
• Widely spaced angular get in touch with bearings provide productivity shaft with excessive radial and axial load capability
• Plasma nitride heat therapy for gears for wonderful surface wear and shear strength
• Sealed to IP65 to protect 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
Body 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 For NOMINAL TORQUE (%)94 – 97
CUSTOM VERSIONS AVAILABLEYes
The Planetary (Epicyclical) Gear System as the “System of preference” 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 definitely the main characteristic requirement of a servo gearboxes; backlash can be a way of measuring the accuracy of the planetary gearbox.
The fact is, fixed-axis, standard, “spur” gear arrangement systems could be designed and constructed just as easily for low backlash requirements. Furthermore, low backlash isn’t an absolute requirement for servo-primarily based automation applications. A moderately low backlash is highly recommended (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-resolution motor-feedback equipment and associated motion controllers it is easy to compensate for backlash anytime there exists a modify in the rotation or torque-load direction.
If, for as soon as, we discount backlash, in that case what are the causes for selecting a even more expensive, seemingly more complex planetary devices for servo gearheads? What positive aspects do planetary gears give?
High Torque Density: Compact Design
An important requirement of automation applications is excessive torque capacity in a concise and light package. This huge torque density requirement (a high torque/quantity or torque/pounds ratio) is important for automation applications with changing huge dynamic loads to avoid additional system inertia.
Depending upon the number of planets, planetary devices distribute the transferred torque through multiple equipment mesh points. This means a planetary gear with declare three planets can transfer three times the torque of an identical sized fixed axis “common” spur gear system
Rotational Stiffness/Elasticity
High rotational (torsional) stiffness, or minimized elastic windup, is important for applications with elevated positioning accuracy and repeatability requirements; especially under fluctuating loading conditions. The load distribution unto multiple equipment mesh points implies that the load is reinforced by N contacts (where N = number of planet gears) consequently increasing the torsional stiffness of the gearbox by point N. This means it noticeably lowers the lost movement compared to a similar size standard gearbox; and this is what is desired.
Low Inertia
Added inertia results in an added torque/energy requirement of both acceleration and deceleration. The smaller gears in planetary system lead to lower inertia. Compared to a same torque score standard gearbox, this is a reasonable approximation to say that the planetary gearbox inertia is smaller by the square of the amount of planets. Once again, this advantage can be rooted in the distribution or “branching” of the load into multiple gear mesh locations.
High Speeds
Modern servomotors run at high rpm’s, hence a servo gearbox must be in a position to operate in a trusted manner at high input speeds. For servomotors, 3,000 rpm is virtually the standard, and actually speeds are frequently increasing to be able to optimize, increasingly complex application requirements. Servomotors running at speeds more than 10,000 rpm are not unusual. From a score perspective, with increased acceleration the power density of the electric motor increases proportionally with no real size increase of the electric motor or electronic drive. Thus, the amp rating stays about the same while only the voltage should be increased. A significant factor is in regards to the lubrication at excessive operating speeds. Set axis spur gears will exhibit lubrication “starvation” and quickly fail if operating at high speeds as the lubricant is usually slung away. Only distinctive means such as expensive pressurized forced lubrication systems can solve this problem. Grease lubrication is impractical as a result of its “tunneling effect,” in which the grease, over time, is pushed apart and cannot circulation back to the mesh.
In planetary systems the lubricant cannot escape. It really is continually redistributed, “pushed and pulled” or “mixed” in to the gear contacts, ensuring safe lubrication practically in virtually any mounting situation and at any swiftness. Furthermore, planetary gearboxes can be grease lubricated. This characteristic is definitely inherent in planetary gearing as a result of the relative movement between the several gears creating the arrangement.
The Best ‘Balanced’ Planetary Ratio from a Torque Density Viewpoint
For less difficult computation, it is favored that the planetary gearbox ratio is an precise 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 benefit for the pc/servo/motion controller. In fact, as we will see, 10:1 or higher ratios are the weakest, using minimal “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 will be of this simple planetary design. Number 2a illustrates a cross-section of this sort of a planetary gear arrangement with its central sun gear, multiple planets (3), and the ring gear. This is of the ratio of a planetary gearbox demonstrated in the body is obtained directly from the unique kinematics of the system. 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, the sun gear would need to possess the same size as the ring gear. Figure 2b shows the sun gear size for numerous ratios. With increased ratio sunlight gear diameter (size) is decreasing.
Since gear size affects 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 simple system. At 3:1 ratio, the sun gear is significant and the planets are small. The planets are becoming “skinny walled”, limiting the space for the planet bearings and carrier pins, consequently limiting the loadability. The 4:1 ratio is definitely a well-well-balanced ratio, with sunshine and planets getting the same size. 5:1 and 6:1 ratios still yield quite good balanced gear sizes between planets and sun. With larger ratios approaching 10:1, the small sun gear becomes a strong limiting component for the transferable torque. Simple planetary models with 10:1 ratios have really small sunlight gears, which sharply limits torque rating.
How Positioning Accuracy and Repeatability is Affected by the Precision and Top quality School of the Servo Gearhead
As previously mentioned, this is a general misconception that the backlash of a gearbox is a way of measuring the product quality or precision. The truth is that the backlash possesses practically nothing to do with the quality or accuracy of a gear. Just the consistency of the backlash can be viewed as, up to certain degree, a form of measure of gear top quality. From the application perspective the relevant concern is, “What gear houses are influencing the precision of the motion?”
Positioning reliability is a measure of how specific a desired situation is reached. In a shut loop system the primary determining/influencing factors of the positioning reliability are the accuracy and resolution of the feedback machine and where the placement can be measured. If the positioning is usually measured at the ultimate output of the actuator, the effect of the mechanical elements can be practically eliminated. (Direct position measurement is employed mainly in very high precision applications such as machine tools). In applications with less positioning accuracy need, the feedback transmission is made by a feedback devise (resolver, encoder) in the engine. In this instance auxiliary mechanical components mounted on the motor like a gearbox, couplings, pulleys, belts, etc. will effect the positioning accuracy.
We manufacture and style high-quality gears together with complete speed-reduction devices. For build-to-print custom parts, assemblies, style, engineering and manufacturing providers get in touch with our engineering group.
Speed reducers and equipment trains can be classified according to equipment type together with relative position of insight and productivity 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 might not exactly be interested in selecting a ready-to-use acceleration reducer. For anybody who wish to design your personal special gear teach or speed reducer we provide a broad range of accuracy gears, types, sizes and material, available from stock.