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 motor torque, and thus current, would need to be as many times better as the lowering ratio which is used. Moog offers an array of windings in each frame size that, coupled with an array of reduction ratios, offers an assortment of solution to result requirements. Each combination of engine and gearhead offers one of a kind advantages.
Precision Planetary Gearheads
gearheads
32 mm LOW PRICED Planetary Gearhead
32 mm Precision Planetary Gearhead
52 mm Accuracy Planetary Gearhead
62 mm Accuracy Planetary Gearhead
81 mm Precision Planetary Gearhead
120 mm Accuracy Planetary Gearhead
Precision planetary gearhead.
Series P high precision inline planetary servo drive will meet your most demanding automation applications. The compact style, universal housing with accuracy bearings and precision planetary gearing provides high torque density and will be offering high positioning functionality. Series P offers precise ratios from 3:1 through 40:1 with the best efficiency and cheapest 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: Matches any servo motor
Output Options: End result 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 any given envelope
Balanced planetary kinematics by high speeds combined with the associated load sharing make planetary-type gearheads perfect for servo applications
Accurate helical technology provides improved tooth to tooth contact ratio by 33% vs. spur gearing 12¡ helix angle produces even and quiet operation
One piece planet carrier and output 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, substantial radial loads, low backlash, great input speeds and a little package size. Custom variations 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 give smooth and quiet procedure and create higher electricity density while retaining a little envelope size. Obtainable in multiple frame 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 even more torque ability, lower backlash, and noiseless operation
• Ring gear minimize into housing provides increased torsional stiffness
• Widely spaced angular get in touch with bearings provide outcome shaft with huge radial and axial load capability
• Plasma nitride heat therapy for gears for excellent surface use and shear strength
• Sealed to IP65 to safeguard against harsh environments
• Mounting products for direct and convenient assembly to precision planetary gearbox 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 Rate (RPM)6000
AMOUNT OF PROTECTION (IP)IP65
EFFICIENCY By NOMINAL TORQUE (%)94 – 97
CUSTOM VERSIONS AVAILABLEYes
The Planetary (Epicyclical) Gear System as the “Program of preference” for Servo Gearheads
Frequent misconceptions regarding planetary gears systems involve backlash: Planetary systems are used for servo gearheads because of their inherent low backlash; low backlash can be 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 can be designed and created only as easily for low backlash requirements. Furthermore, low backlash is not an absolute requirement for servo-established automation applications. A moderately low backlash is a good idea (in applications with high start/stop, forwards/reverse cycles) in order to avoid inner shock loads in the gear mesh. That said, with today’s high-image resolution motor-feedback gadgets 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, after that what are the factors for selecting a more expensive, seemingly more complex planetary devices for servo gearheads? What advantages do planetary gears provide?
High Torque Density: Small Design
An important requirement for automation applications is great torque capability in a concise and light bundle. This excessive torque density requirement (a higher torque/volume or torque/fat ratio) is very important to automation applications with changing large dynamic loads to avoid additional system inertia.
Depending upon the number of planets, planetary systems distribute the transferred torque through multiple gear mesh points. This means a planetary equipment with claim three planets can transfer three times the torque of a similar sized fixed axis “regular” 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; specifically under fluctuating loading conditions. The strain distribution unto multiple gear mesh points implies that the load is backed by N contacts (where N = quantity of planet gears) consequently raising the torsional stiffness of the gearbox by point N. This implies it noticeably lowers the lost movement compared to an identical size standard gearbox; which is what is desired.
Low Inertia
Added inertia results within an added torque/energy requirement of both acceleration and deceleration. Small gears in planetary program cause lower inertia. Compared to a same torque score standard gearbox, it is a fair approximation to state that the planetary gearbox inertia is certainly smaller by the square of the amount of planets. Once again, this advantage is rooted in the distribution or “branching” of the load into multiple equipment mesh locations.
High Speeds
Modern day servomotors run at great rpm’s, hence a servo gearbox must be in a position to operate in a reliable manner at high type speeds. For servomotors, 3,000 rpm is almost the standard, and actually speeds are frequently increasing as a way to optimize, increasingly intricate application requirements. Servomotors running at speeds more than 10,000 rpm aren’t unusual. From a score point of view, with increased speed the energy density of the electric motor increases proportionally with no real size enhance of the engine or electronic drive. Hence, the amp rating remains about the same while just the voltage must be increased. A key point is with regards to the lubrication at great operating speeds. Fixed axis spur gears will exhibit lubrication “starvation” and quickly fail if working at high speeds for the reason that lubricant is definitely slung away. Only distinctive means such as pricey pressurized forced lubrication systems can solve this problem. Grease lubrication is usually impractical because of its “tunneling effect,” in which the grease, over time, is pushed apart and cannot move back to the mesh.
In planetary systems the lubricant cannot escape. It really is consistently redistributed, “pushed and pulled” or “mixed” in to the gear contacts, ensuring safe lubrication practically in any mounting position and at any acceleration. Furthermore, planetary gearboxes could be grease lubricated. This characteristic is definitely inherent in planetary gearing because of the relative motion between the various gears making up the arrangement.
The Best ‘Balanced’ Planetary Ratio from a Torque Density Perspective
For much easier computation, it is recommended that the planetary gearbox ratio is 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 this has no practical gain for the computer/servo/motion controller. Essentially, as we will have, 10:1 or higher ratios are 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. The vast majority of the epicyclical gears found in servo applications will be of this simple planetary design. Shape 2a illustrates a cross-section of such a planetary gear arrangement using its central sun equipment, multiple planets (3), and the ring gear. This is of the ratio of a planetary gearbox shown in the figure is obtained straight from the initial kinematics of the system. It is obvious a 2:1 ratio isn’t possible in a straightforward planetary gear program, since to satisfy the previous equation for a ratio of 2:1, sunlight gear would have to have the same size as the ring gear. Figure 2b shows the sun gear size for diverse ratios. With an increase of ratio the sun gear diameter (size) is decreasing.
Since gear size impacts loadability, the ratio is a strong and direct effect to the torque ranking. Figure 3a reveals 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 will be 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 can be a well-balanced ratio, with sunlight and planets having the same size. 5:1 and 6:1 ratios still yield fairly good balanced equipment sizes between planets and sunshine. With bigger ratios approaching 10:1, the tiny sun equipment becomes a solid limiting point for the transferable torque. Simple planetary styles with 10:1 ratios have really small sun gears, which sharply limitations torque rating.
How Positioning Precision and Repeatability is Suffering from the Precision and 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 product quality or precision. The truth is that the backlash has 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 perspective the relevant concern is, “What gear properties are influencing the precision of the motion?”
Positioning accuracy is a way of measuring how specific a desired situation is reached. In a shut loop system the primary determining/influencing factors of the positioning precision will be the accuracy and image resolution of the feedback system and where the location is certainly measured. If the positioning can be measured at the final productivity of the actuator, the impact of the mechanical components can be practically eliminated. (Immediate position measurement is utilized mainly in high accuracy applications such as machine equipment). In applications with less positioning accuracy necessity, the feedback transmission is produced by a opinions devise (resolver, encoder) in the electric motor. In this case auxiliary mechanical components attached to the motor for instance a gearbox, couplings, pulleys, belts, etc. will influence the positioning accuracy.
We manufacture and style high-quality gears and also complete speed-reduction devices. For build-to-print customized parts, assemblies, style, engineering and manufacturing companies get in touch with our engineering group.
Speed reducers and equipment trains can be categorized according to gear type together with relative position of input and result shafts. SDP/SI offers a wide variety of standard catalog items:
gearheads and speed reducers
planetary and spur gearheads
correct angle and dual outcome right angle planetary gearheads
We realize you may well not be interested in selecting a ready-to-use speed reducer. For those of you who want to design your very own special gear coach or velocity reducer we give a broad range of precision gears, types, sizes and material, available from stock.