Our gearbox expertise for your application
What makes a precision gearbox? How do cycloidal gearboxes work? What does backlash mean? You have questions – we provide the answers.
Our FAQ section brings together specialist knowledge that will help you advance your projects: from basic explanations of terms to comparisons of different types of gearboxes and important technical contexts. Clearly formulated, vividly presented and precisely to the point. Immerse yourself in the world of gear technology and gain expert knowledge for your technical challenges.
Technologies Explanation of terms Gearbox types
Technologies
Functional principle of cycloidal gears
The innovative, extremely powerful technology offers unbeatable advantages for your automation.
Thanks to their special technology, cycloidal gears offer a high degree of precision, dynamics, torsional rigidity and compactness. They are extremely resilient, resistant and low-wear and provide high-precision positioning over their entire service life. The integrated angular contact ball bearings absorb axial and radial loads as well as bending moments and contribute to the high tilting rigidity and resistance to impact and overload. The virtually backlash-free precision gearboxes are particularly lightweight, space-saving and yet powerful - ideal for all applications that require maximum performance in a compact design.
In the first stage, the rotary motion of the drive or servo motor is transmitted to the spur gears via the input shaft. The speed is reduced according to the reduction ratio....
Functional principle of strain wave gears
Unique technology with decisive advantages - on a technical, design and economic level.
strain wave gears are widely used in robotics & automation. Our development engineers have optimized the proven technology and achieved continuous improvement of the product properties as well as the processes and manufacturing methods. Their benefits: excellent performance data, comprehensive customizing and integration options, automotive-compliant production, optimum cost-effectiveness and a unique service level.
strain wave gears consist of just three components: Wave generator, flexspline and ring gear (circular spline). It is characterized by power transmission via an elastic element, the flexspline...
Welcome to the Neco® world!
Why make things complicated when they can be simple? We don't know the answer to this either, which is why we have created a world of gearboxes with Neco® that makes your work as easy as possible. The solutions combine cutting-edge technology with high flexibility and intuitive operation and help you to make processes faster, safer and more economical. This allows you to concentrate fully on the essentials in your automation. Experience gearboxes in a new way - it's so easy!
When choosing the right gearbox, it's no longer just performance, dynamics, efficiency and reliability that count...
Digitalization & gearboxes: your path to the future
Digitalization is revolutionizing production processes, opening up new growth potential and paving the way for innovative business models, applications and services. Gearboxes play a key role here: as the heart of machines and robots, they are an indispensable component of the manufacturing industry - and a decisive driver of digital transformation. We answer the most important questions and show you intelligent solutions for the digitalization of gearboxes and drives.
Digital gearboxes combine high-precision mechanics with smart sensor technology. They record and analyze operating data, communicate with higher-level controllers or external systems and enable....
Explanation of terms
What does acceleration torque mean?
The acceleration torque, or dynamic torque, is the moment, needed to overcome the inertia. It is the product of inertia and angular acceleration. There is a direct relationship between the acceleration time and the life of the gearbox. A reduction of the acceleration time causes a higher acceleration torque, but simultaneously also a lower maximum rotational speed. The average torque and therefore the life of the gearbox increase again starting at a specific point. In the case of a vertical axis of rotation, this is often the case at one-third of the cycle time; for a horizontal axis of rotation, this point is more difficult to determine.
Cycloidal gears enable much higher acceleration torques than comparable planetary gears. That is because of their special design. The contact of the cams to the pins installed in the case guarantees optimal force transmission…..
What does main bearing mean?
Gear bearings absorb axial and radial forces, as well as bending moments, which makes them a functionally critical and defining component. Properties such as precision, dynamics and load-bearing capacity are also defined by the specific bearing solution. Nabtesco cycloidal gears feature an integrated robust main bearing that allows them to absorb 250 % higher bending moments than conventional planetary gears of a comparable size.
Cycloidal gears with robust main bearing
Two angular ball bearings of identical size are used in a mirror-image arrangement. By design, the bearings in cycloidal gears have a much larger diameter than those in planetary gears. This provides plenty of space for numerous rolling elements. It’s a simple formula: the more rolling elements, the more powerful the bearing. An O-arrangement is used for adjustment, due to the higher allowable moment compared with an X-arrangement.
Angular ball bearings are especially effective in dynamic applications…
What does torsional rigidity mean?
Torsional rigidity specifies the resistance of a gear against twisting around the longitudinal axis. High torsional rigidity minimises elastic deformation that occurs when the gear is subjected to torsional loads. The result is excellent precision.
Measuring torsional rigidity
Torsional rigidity, like backlash, is ascertained by scanning the hysteresis. With the drive shaft fixed, the gear output shaft is subjected to torque – first increasing, then decreasing, then increasing again. Then the gradient of the straight lines at the end of the hysteresis curve is measured at 50-100 % of the rated torque. This gradient corresponds to the torsional rigidity. Torsional rigidity is specified in Nm/arc.min. A higher value corresponds to higher gear precision. Torsionally rigid gears not only achieve extremely precise positioning, but also higher acceleration torques, since overshoot and oscillations are eliminated even in highly dynamic situations.
Torsional rigidity in combination with low torques…
What does backlash mean?
Backlash and hysteresis loss largely characterise the precision of a gearbox. A lower value corresponds to higher gear precision. Hysteresis loss is measured by scanning the hysteresis. In a standardised test procedure the gear output shaft is fixed and then subjected first to an increasing torque, followed by decreasing and then increasing torque again. The angular tolerance between the gear input and output shaft at a torque of 0 Nm is referred to as hysteresis loss. Backlash and hysteresis loss are specified in arc.min (= minutes of arc). One arcminute is defined as one 60th of a degree.
Minimal backlash
The hysteresis loss in Nabtesco cycloidal gears is less than one arcminute. The majority of the loss results from friction, which occurs in every gearbox in normal operation. The purely mechanical backlash is between 0.1 and 0.3 arc.min, which means there is no perceptible backlash at the gear output shaft.
Another important characteristic is the lost motion……
What does repeatability mean?
Repeatability describes the accuracy of repeatedly moving to a position with the same speed and acceleration. A value of ±5 to 10 arcseconds is currently considered standard in robotics. Other applications, such as positioning, require precision down to a hundredth of a millimetre. Excellent repeatability can be achieved, for example, by calibration of the robot or of other applications.
Repeatability, positioning accuracy and transmission accuracy
Besides repeatability, positioning accuracy is another key parameter. Positioning accuracy defines the speed at which a desired position can be reached. Another important aspect here is the transmission speed, which reflects the position error of the initial motion that is transmitted at the gear output shaft. Transmission accuracy results primarily from the production tolerances and the pins installed in the case, and is specific to each individual gearbox. Positioning accuracy is defined primarily by transmission error and hysteresis loss.
The precision of a gearbox depends on numerous gear-specific…..
Gearbox types
Are you looking for a planetary gearbox?
Applications that require particularly high precision present design engineers with a choice: which gearbox is the right one? Above all, compact precision gearboxes with a long service life are in demand. In many cases, planetary gearboxes are considered the optimal solution. However, this is not always the best option. Do you value maximum precision, absolute reliability and minimum space requirements? Then our cycloidal gearboxes and strain wave gears are just right for you!
The areas of application of the gearbox types overlap, but our precision gearboxes can replace planetary gearboxes in many applications - be it in plant engineering, robotics, machine tool construction or medical technology.
Cycloidal gears and strain wave gears have an advantage over planetary gears in many applications....
Are you looking for a helical gearbox?
In most cases, helical gearboxes do not compete with cycloidal gearboxes and strain wave gears - the technical performance data, specific advantages and typical areas of application are too different. Nevertheless, there are some areas of application in which a switch from spur gearboxes to cycloidal gearboxes could be worthwhile. These include, for example, welding positioners, the printing industry and conveyor systems in packaging technology and the food industry, where stations have to be approached precisely or where intermittent transportation takes place.
Cycloidal gears and strain wave gears offer a number of advantages over spur gears...
Are you looking for a bevel gearbox?
In bevel gearboxes, the input shaft and output shaft are at an angle to each other. This results in a deflection of the axis of rotation and enables the motor to be mounted at a right angle. The right-angle gearboxes can be easily combined with other gearbox types and thus open up space-saving machine concepts. The RDR and RS-A series also use a bevel gear pre-stage to transmit movements and forces at an angle.
If cycloidal gearboxes are combined with a bevel gearbox, this results in advantages in terms of motor attachment...
Are you looking for a worm gearbox?
Worm gearboxes are a robust solution for applications with high reduction ratios and limited space and are rarely used in precision applications. Nevertheless, there are points of contact. For example in the area of rotary tables. Here, the fields of application of worm gearboxes and cycloidal gearboxes overlap - with significant advantages in favor of our precision gearboxes. Ball screw drives, strictly speaking also worm gearboxes, benefit from a combination with strain wave gears.
Do worm gearboxes, cycloidal gearboxes and strain wave gears have a common denominator? Find out...
Are you looking for a servo gearbox?
Servo gearboxes enable high speeds and accelerations and at the same time have high positioning and speed accuracy. In addition, they are characterized by high torsional rigidity and low backlash - and thus fully meet the requirements of highly dynamic applications.
The servo gearboxes from Nabtesco are very precise, extremely robust and absolutely reliable - with a particularly compact design. The two-stage reduction principle...
Are you looking for an angular gearbox?
In right-angle gearboxes, the input shaft and output shaft are offset from each other. This allows torques, speeds, directions of rotation and/or forces to be transmitted at an angle - an ideal solution where space is limited. Based on cycloidal gearbox technology or in combination with a strain wave gear, you receive high-precision, reliable and low-maintenance drive solutions for robotics and general mechanical and plant engineering.
Is your installation space limited? Find out more about the use of angular gearboxes, cycloidal gearboxes & strain wave gears...
Do you already know our mascots Nabby & Tessy? The two robots bring our technologies to life in the truest sense of the word and accompany you through our world of gearboxes. They will help you find products, explain technical details and give you tips and tricks.
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