Linear axes, linear tables, linear modules for precise linear systems

Linear axes and linear tables for precision results with high dynamic performance

We are more than happy to calculate (dimension) an axis or even an entire system of linear modules for a very wide range of applications and various equipment components. Our linear modules are driven by ball screw or acme screw drives - where desired also with toothed belts or rack and pinion. Mounting rails or rollers ensure accurate guidance. At Lenze, you not only receive the axis as a component. We also assist you with selecting the right geared motors incl. servo technology and controllers, as well as with the programming of the control unit and commissioning. Hence, what you receive is an optimally calibrated handling system. With us, you can quickly and easily realise your gantry robot!

Drive systems

Depending on the series, the linear axes are manufactured with toothed belt drives, spindle drives, rack drives, and linear motor drives. Every drive system has certain advantages and disadvantages. Toothed belt drives are e.g. particularly suitable for quick positioning. Spindle drives exhibit e.g. a high positioning accuracy. Based on your requirements, the loads to be transported, required speeds, and the forces which occur, we will assist you with selecting the right linear axes and system.

Toothed belt drive

Linear axes with a toothed belt drive are well-suited for fast handling and positioning tasks. All axes are equipped with AT or STD toothed belts. These are extruded polyurethane belts with integrated steel reinforcements. The AT toothed belts come in the zero gap version. The use of black toothed belts prevents discolouration of the toothed belts under UV radiation.

These toothed belts are also characterised by the following features:

Low wear
Maintenance-free
High tensile strength and low stretching
Extremely high accuracy - pitch error ± 0.2mm/m
UV-resistant
Temperature range -25 °C to +75 °C, special version available for use under -25 °
Low-noise
Designs with approval for use in the food industry

Spindle drive

Linear axes with a spindle drive can be equipped with both ball screw drives as well as acme screw drives. Spindle drives are particularly suited for meeting high demands in terms of positioning and repeat accuracy in combination with high rigidity of the drive element.

The drives can be adapted directly via coupling and coupling bell or via a guide belt drive. Advantages:

Long traverse path with high positioning accuracy
High velocities with long traverse paths thanks to the optional use of spindle supports
Different leadscrew pitches to choose from
Self-locking when acme screw drives are used
High feed forces
High drive stiffness
gearbox not necessary in some cases

Rack drive

Linear axes with a rack drive are characterised by a very high operational reliability, making them particularly suited to vertical applications. Any number of rack and pinion elements can be installed next to each other.

The inductively hardened rack and pinion elements and gear wheels ensure a very long service life. Advantages of the drive:

Unlimited lengths theoretically possible
Multiple drive units possible
High feed forces
Maximum drive stiffness, even with high loads

Guide systems

Linear axes can, depending on the series, be outfitted with linear guides or various types of roller guides. These options make it possible to react extremely flexibly to the requirements of the application and the ambient conditions and select an optimal configuration of the linear axes. If linear axes are used purely as a drive component, it is also possible to choose a design without guide elements.

Linear guides

Linear axes of all series are outfitted with linear guides with an integrated ball chain. Due to the arrangement of the raceways at a 45 ° angle, the linear guides are suitable for universal use and exhibit the same load ratings in all main load directions. The special properties of our linear guides with ball chain include the integrated lubricant reservoirs.

The use of these linear guides provides the following advantages:

High load ratings
Long service life
Long-term maintenance-free
Low heat generation
High tolerance compensation and error compensation ability thanks to X - arrangement of raceways
Low noise level
Very smooth running
High speeds of up to 5 m/s
High acceleration levels of up to 50 m/s²

Roller guides

Depending on the series, various types of rollers can be used with the roller guides.

All designs of the AXC and AXDL series are available with roller guides in a steel version. This system consists of rollers which roll on smoothened, hardened steel shafts incorporated into the aluminium profile. The steel shafts are constantly wetted with lubricating oil from an oil reservoir that can be refilled from the outside. The rollers are dust-proof, double-row angular contact ball bearings with a profiled outer ring. Thanks to an eccentric bearing arrangement for half the rollers, the guide system can be configured precisely, ensuring that it always has the correct factory-set pretension and/or zero backlash.

This technology ensures outstanding operating characteristics and offers the following advantages:

Extremely cost-effective guide system, particularly for large lengths
Long service life thanks to the use of dust-proof bearings and an internal arrangement of the rollers in the profile
Extremely high speeds of up to 15 m/s
High acceleration levels of up to 50 m/s²

Polymer rollers

Linear axes of the AXF series can also optionally be outfitted with polymer rollers. In this variant, the rollers run directly on the surfaces of the aluminium profile. The configuration of the pretension is performed during installation via a spring element in the slide unit consisting of two parts. The polymer rollers at the slide unit are on slide bearings. Linear axes with this guide system can also be used in wet areas, in extremely dirty environments, or in combination with aggressive media.

This guide system is characterised by the following properties:

Very high resistance to media
Maintenance-free and dirt-resistant rollers
Good mechanical damping properties
Internal arrangement of rollers
Extremely high speeds of up to 7 m/s
Acceleration levels of up to 30 m/s²

Definitions of selection criteria for linear axes

The selection of the linear axes may be based on the following criteria:

Repeat accuracy

For repeat accuracy, a particular point is moved to multiple times from one direction and from the same starting point, and the deviation from the setpoint is measured. The procedure is repeated for various points. ± 50% of the difference between the maximum and minimum deviation is specified as repeat accuracy.

Positioning accuracy

When measuring positioning accuracy, multiple points are moved to in one direction and the difference between the setpoint distance and the actual path travelled is measured. The positioning accuracy is the absolute maximum difference.

Running parallelism

A dial gauge installed in the middle of the slide unit is moved over the entire stroke. The running parallelism is the maximum difference of the values read off the gauge.

Reversal error of ball screw drives

The slide unit is moved using a ball screw drive against a dial gauge as a reference point. Subsequently, a load is applied to the slide unit in the same direction via an external force, after which the load is removed. The reversal error is the maximum difference between the reference point and the position after applying/removing the load.

Breakaway torque of ball screw drives

The breakaway torque is the necessary drive torque required to overcome the static friction of the system and to start the movement.