Precision precision planetary gearbox planetary Gearheads
The primary reason to use a gearhead is that it makes it possible to regulate a sizable 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 thus current, would need to be as many times increased as the lowering ratio which is used. Moog offers a selection of windings in each framework size that, combined with a selection of reduction ratios, provides an assortment of solution to end result requirements. Each mixture of electric motor and gearhead offers exceptional advantages.
Precision Planetary Gearheads
32 mm Low Cost Planetary Gearhead
32 mm Precision Planetary Gearhead
52 mm Accuracy Planetary Gearhead
62 mm Accuracy Planetary Gearhead
81 mm Accuracy Planetary Gearhead
120 mm Accuracy Planetary Gearhead
Precision planetary gearhead.
Series P high precision inline planetary servo travel will gratify your most demanding automation applications. The compact style, universal housing with accuracy bearings and precision planetary gearing provides large torque density and will be offering high positioning effectiveness. Series P offers specific ratios from 3:1 through 40:1 with the best efficiency and cheapest backlash in the industry.
Sizes: 60, 90, 115, 140, 180 and 220
Productivity Torque: Up to at least one 1,500 Nm (13,275 lb.in.)
Equipment Ratios: Up to 100:1 in two stages
Input Options: Matches any servo motor
Output Options: Outcome with or without keyway
As a result of 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 the associated load sharing help to make 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 smooth and quiet operation
One piece planet carrier and result shaft design reduces backlash
Single step machining process
Assures 100% concentricity Heightens torsional rigidity
Efficient lubrication forever
The excessive precision PS-series inline helical planetary gearheads are available in 60-220mm frame sizes and provide high torque, great radial loads, low backlash, huge input speeds and a tiny package size. Custom types are possible
Print Product Overview
Ever-Power PS-series gearheads supply the highest overall performance to meet your applications torque, inertia, speed and reliability requirements. Helical gears present smooth and quiet operation and create higher ability density while maintaining a tiny envelope size. Available in multiple framework sizes and ratios to meet many different application requirements.
• Industrial automation
• Semiconductor and electronics
• Food and beverage
• Health and beauty
• Life science
Features and Benefits
• Helical gears provide even more torque ability, lower backlash, and tranquil operation
• Ring gear lower into housing provides greater torsional stiffness
• Widely spaced angular speak to bearings provide output shaft with high radial and axial load capability
• Plasma nitride heat treatment for gears for superb surface have on and shear strength
• Sealed to IP65 to safeguard against harsh environments
• Mounting kits for direct and easy assembly to hundreds of different motors
• Antenna pedestals
• Robotic actuation and propulsion
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 Acceleration (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 preference” for Servo Gearheads
Regular misconceptions regarding planetary gears systems involve backlash: Planetary systems are used for servo gearheads because of their inherent low backlash; low backlash is normally the main characteristic requirement of a servo gearboxes; backlash is certainly a way of measuring the accuracy of the planetary gearbox.
The truth is, fixed-axis, standard, “spur” gear arrangement systems could be designed and made just as easily for low backlash requirements. Furthermore, low backlash isn’t an absolute requirement of servo-based mostly automation applications. A moderately low backlash is highly recommended (in applications with high start/stop, frontward/reverse cycles) to avoid interior shock loads in the gear mesh. That said, with today’s high-image resolution motor-feedback equipment and associated motion controllers it is simple to compensate for backlash anytime you will find a switch in the rotation or torque-load direction.
If, for the moment, we discount backlash, in that case what are the causes for selecting a even more expensive, seemingly more technical planetary systems for servo gearheads? What advantages do planetary gears present?
High Torque Density: Compact Design
An important requirement for automation applications is high torque ability in a concise and light package. This huge torque density requirement (a higher torque/quantity or torque/weight ratio) is very important to automation applications with changing substantial dynamic loads in order to avoid additional system inertia.
Depending upon the number of planets, planetary systems distribute the transferred torque through multiple gear mesh points. This implies a planetary equipment with declare three planets can transfer three times the torque of a similar sized fixed axis “common” spur gear system
High rotational (torsional) stiffness, or minimized elastic windup, is very important to applications with elevated positioning accuracy and repeatability requirements; especially under fluctuating loading circumstances. The load distribution unto multiple gear mesh points ensures that the load is reinforced by N contacts (where N = quantity of planet gears) hence increasing the torsional stiffness of the gearbox by factor N. This means it considerably lowers the lost action compared to an identical size standard gearbox; which is what is desired.
Added inertia results within an further torque/energy requirement for both acceleration and deceleration. The smaller gears in planetary system cause lower inertia. Compared to a same torque rating standard gearbox, this is a fair approximation to say that the planetary gearbox inertia is smaller by the square of the number of planets. Again, this advantage is usually rooted in the distribution or “branching” of the strain into multiple gear mesh locations.
Modern servomotors run at huge rpm’s, hence a servo gearbox should be able to operate in a trusted manner at high source 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 operating at speeds in excess of 10,000 rpm are not unusual. From a rating perspective, with increased velocity the energy density of the motor increases proportionally with no real size maximize of the electric motor or electronic drive. As a result, the amp rating remains about the same while just the voltage should be increased. A significant factor is in regards to the lubrication at huge operating speeds. Set axis spur gears will exhibit lubrication “starvation” and quickly fail if jogging at high speeds because the lubricant can be slung away. Only specialized means such as high-priced pressurized forced lubrication devices can solve this problem. Grease lubrication is definitely impractical due to its “tunneling effect,” in which the grease, over time, is pushed away and cannot flow back into the mesh.
In planetary systems the lubricant cannot escape. It really is continuously redistributed, “pushed and pulled” or “mixed” into the gear contacts, ensuring safe lubrication practically in any mounting placement and at any swiftness. Furthermore, planetary gearboxes can be grease lubricated. This characteristic can be inherent in planetary gearing because of the relative motion between the several gears making up the arrangement.
The Best ‘Balanced’ Planetary Ratio from a Torque Density Perspective
For less complicated computation, it is preferred 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 advantage for the computer/servo/motion controller. Actually, as we will see, 10:1 or more ratios are the weakest, using the least “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 happen to be of the simple planetary design. Body 2a illustrates a cross-section of this kind of a planetary gear set up using its central sun equipment, multiple planets (3), and the ring gear. This is of the ratio of a planetary gearbox demonstrated in the determine is obtained immediately from the initial kinematics of the machine. It is obvious a 2:1 ratio isn’t possible in a simple planetary gear program, since to satisfy the prior equation for a ratio of 2:1, sunlight gear would have to possess the same size as the ring gear. Figure 2b shows the sun gear size for several ratios. With increased ratio the sun gear diameter (size) is decreasing.
Since gear size impacts loadability, the ratio is a solid and direct affect to the torque ranking. Figure 3a shows the gears in a 3:1, 4:1, and 10:1 basic system. At 3:1 ratio, the sun gear is significant and the planets will be small. The planets have become “thin walled”, limiting the area for the earth bearings and carrier pins, consequently limiting the loadability. The 4:1 ratio is normally a well-well balanced ratio, with sunshine and planets having the same size. 5:1 and 6:1 ratios still yield pretty good balanced equipment sizes between planets and sunshine. With higher ratios approaching 10:1, the tiny sun gear becomes a solid limiting element for the transferable torque. Simple planetary models with 10:1 ratios have very small sunlight gears, which sharply restrictions torque rating.
How Positioning Precision and Repeatability is Suffering from 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 quality or precision. The fact is that the backlash offers practically nothing to perform with the product quality or precision of a gear. Only the consistency of the backlash can be viewed as, up to certain level, a form of measure of gear quality. From the application viewpoint the relevant dilemma is, “What gear houses are influencing the precision of the motion?”
Positioning accuracy is a way of measuring how actual a desired posture is reached. In a shut loop system the primary determining/influencing elements of the positioning reliability will be the accuracy and resolution of the feedback product and where the situation is normally measured. If the positioning is certainly measured at the ultimate output of the actuator, the effect of the mechanical parts can be practically eliminated. (Immediate position measurement can be used mainly in very high accuracy applications such as for example machine equipment). In applications with a lower positioning accuracy need, the feedback transmission is produced by a opinions devise (resolver, encoder) in the motor. In this case 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 in addition to complete speed-reduction devices. For build-to-print custom parts, assemblies, style, engineering and manufacturing products and services speak to our engineering group.
Speed reducers and gear trains can be categorized according to gear type as well as relative position of insight and end result shafts. SDP/SI offers a wide variety of standard catalog items:
gearheads and speed reducers
planetary and spur gearheads
correct angle and dual productivity right angle planetary gearheads
We realize you might not exactly be interested in selecting a ready-to-use rate reducer. For anybody who wish to design your individual special gear train or acceleration reducer we offer a broad range of precision gears, types, sizes and materials, available from stock.
Precision precision planetary gearbox planetary Gearheads