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Miniature linear recirculating ball bearing and guideway assemblies (MAI 81)

Miniature linear recirculating ball bearing and guideway assemblies (MAI 81)
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Miniature linear recirculating ball bearing and guideway assemblies (MAI 81)

Product catalog summary
Overview: The document focuses on the design and application of miniature linear recirculating ball bearing and guideway assemblies, emphasizing corrosion-resistant, two-row, and four-row configurations. These systems are essential for applications requiring compact size, high load capacity, and rigidity.
Specifications:
  • Two-row assemblies offer moderate load capacity and modularity, allowing interchangeability of guideways and carriages within the same class.
  • Four-row assemblies, such as the KUME..C, provide high load capacity and rigidity, suitable for unlimited stroke lengths and often maintenance-free.
Applications: These systems are ideal for sectors like microelectronics, optical equipment, medical devices, and textile machinery, where high speed and uniform running are crucial.
Features:
  • Linear locating bearings for unlimited stroke lengths.
  • Preloaded systems with seals on carriage end faces.
  • Available in wide designs and can be lubricated with oil or grease.
Design and Safety Guidelines:
  • Load carrying capacity is determined by dynamic and static load ratings.
  • Static load safety factor should be at least 3 for high accuracy and smoothness.
  • Interchangeability allows for economical stockholding and easy installation.
Preload and Accuracy:
  • Preload classes affect rigidity, load capacity, and guidance accuracy.
  • Accuracy classes G1 and G2 define tolerances for height and spacing.
Construction Demands: Proper design of the adjacent construction is crucial for optimal performance, ensuring proper alignment and load distribution.
Specifications and Requirements: The document outlines the specifications for two-row assemblies, emphasizing accuracy, rigidity, and load-carrying capacity. Key factors include the geometrical and positional accuracy of mounting surfaces, which should adhere to specified tolerances to ensure system accuracy and longevity.
Mounting Surface Accuracy: Mounting surfaces should be ground or precision milled with a mean roughness value of Ra1.6. Tolerances for support and locating surfaces are detailed, with permissible deviations calculated using specific formulas.
Parallelism and Locating Heights: Parallelism of guideways is crucial, with specific values provided to maintain system integrity. Locating heights and corner radii must conform to specified figures and tables to ensure proper assembly and function.
Sealing and Maintenance: Sealing is critical to prevent damage, with additional seals recommended if standard wipers are insufficient. Carriages can be fitted with sealing strips for contaminated environments, and greasing options are available for specific applications.
Ordering and Designation: Examples of ordering designations are provided, detailing the configuration of carriages and guideways, including size, accuracy, preload class, and additional features like sealing strips or greasing.
Dimension Tables: Comprehensive dimension tables are included, detailing the mass, dimensions, and mounting specifications for various carriage and guideway combinations. Load carrying capacities and moment ratings are also provided.
Accessories and Additional Features: The document mentions accessories like sealing strips and grease injectors, with specific suffixes for different configurations. It also highlights the availability of special grease for clean room applications.
Four-row Assemblies: The document introduces four-row assemblies, noting their complete unit composition, load support capabilities, and maintenance-free design for most applications.
Specifications: Four-row assemblies are corrosion-resistant, suitable for accelerations up to 40 m/s², speeds up to 180 m/min, and operating temperatures from -40°C to 80°C. The carriage and guideway are made from corrosion-resistant, hardened steel with precision-ground raceways.
Design and Safety Guidelines: The load carrying capacity is determined by the basic dynamic and static load ratings. The static load safety factor should not be less than 3 for high accuracy and smoothness. Formulas for calculating the basic rating life and static load safety factor are provided.
Initial Operation and Lubrication: Guideways and carriages are supplied assembled and must be oiled or greased before initial operation. Lubrication should be done using conventional pointed nozzles, and excessive greasing should be avoided.
Preload and Accuracy: Assemblies are available in different preload classes, affecting rigidity, moment load carrying capacity, and guidance accuracy. The assemblies are supplied in accuracy class G2, with specific tolerances for height and spacing.
Mounting and Construction Requirements: The document outlines the importance of geometrical and positional accuracy of mounting surfaces. Deviations from specified tolerances can impair accuracy and reduce operating life. Parallelism and locating heights are also discussed.
Accessories and Ordering: Accessories include contact wipers and grease injectors. The document provides an example of an ordering designation for the assemblies.
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Catalog excerpts

Miniature linear recirculating ball bearing and guideway assemblies (MAI 81)-1

Linear bearings for the miniature applications sector require a dif-ferent approach in the design of guidance systems. While normal criteria such as load carrying capacity, rigidity and operating life are important, the additional factor of size also applies for minia-ture bearing arrangements. However, simply scaling downӔ thestandard sizes to smaller dimensions is not very successful intechnical terms. INA has therefore developed its four-row miniature linear ball bearing and guideway assembly KUME..C. For applications with a lower requirement for load carrying capacity, this high-performance guidance system is supplemented by a two-row guidance system. > Two-row linear recirculating ball bearing andguideway assemblies These units have moderate load carrying capacity,the moment load carrying capacity is moderate to high.Their modular construction allows the exchange ofguideways and carriages within one interchangeability and accuracy class. This gives simpler fitting of guidance systems, easier sourcing of replacement parts and allows very economical stockholding.The saddle plates and guideways are corrosion-resistant. Seals on the end faces of the carriages protect the rolling element system against contamination. The carriages are greased and can be relubricated. The guideways and carriages are also available in a wide version. Four-row linear recirculating ball bearing and guideway assemblies Four-row miniature linear recirculating ball bearing and guideway assemblies KUME..C are established, ready-to-fit guidance systems for unlimited stroke lengths. They have high load carrying capacity and rigidity.Due to the lubricant reservoir in the carriages, they are maintenance-free in many applications. Applications These linear recirculating guidance systems are particularly suitable for applications: in the microelectronics industry andrelated sectors in optical equipment in medical equipment in textile machinery that require high speeds andvery uniform running behaviour where particularly economical miniature guidance systems areneeded for moderate to high load requirements and moderate to high rigidity requirements. > 173 626a

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Miniature linear recirculating ball bearing and guideway assemblies (MAI 81)-2

FeatureMiniature ball bearing andguidewayassembly Characteristic Dimensions/cross-section Load carrying capacity and rigidity Linear locating bearing for unlimited stroke lengths > 173 673 Comprising guideway TKDMand carriage KWEM Two-row, four point contact of rolling elementswith raceways > Can support loads from all directions except for the direction of motion ֖ and moments about all axes Preloaded Seals on end faces of carriages > Greased, can be lubricated with oil or grease Also available as long version Moderate to high > Linear locating bearing for unlimited stroke lengths > 173 668...

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Miniature linear recirculating ball bearing and guideway assemblies (MAI 81)-3

FeatureMiniature linear guidance system Characteristic Load carrying capacity Rigidity Information > Linear locating bearing for unlimited stroke lengths Comprising guideway and carriage, not preassembled Two-row, four point contact of rolling elementswith raceways Preloaded Seals on end faces of carriages Greased, can be lubricated with oil or grease Interchangeable Moderate to highModerate to highMAI 81 > 173 668a Linear locating bearing for unlimited stroke lengths Comprising guideway and carriage Four-row, two point contact of rolling elementswith raceways Preloaded With lubricant reservoir...

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Miniature linear recirculating ball bearing and guideway assemblies (MAI 81)-5

Two-row miniature linear recirculating ball bearing and guideway assemblies corrosion-resistant KWEM..(W) / TKDM..(W) > M k ֋C 18ږ23 1414 > 173 634 Accessories > 173 649 173 652b sealing strips for carriages grease injector for greasing of carriages >

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Miniature linear recirculating ball bearing and guideway assemblies (MAI 81)-6

CN Basic dynamic load rating ( dimension table )C Design and safety guidelinesLoad carrying capacity and life > > NBasic static load rating ( dimension table )HmmDistance between ends of strokeLmmBasic rating life in 100000mL The size of the guidance unit is determined by the load carrying capacity of the individual elements. The load carrying capacity is described in terms of the basic dynamic load rating C and basic static load rating C > ( dimension table ). > h hBasic rating life in operating hoursMNmEquivalent static moment in load directionM Basic rating life The basic rating life is determined...

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Miniature linear recirculating ball bearing and guideway assemblies (MAI 81)-7

Interchangeability The guideways and carriages can be used in any combination within the same accuracy and interchangeability class.This has the following benefits: > 1 economical stockholding simple spare parts sourcing straightforward installation.The preload class is determined by the carriage. Delivered condition The carriage and guideway are not supplied pre-assembled (Figure 1).There is a plastic dummy guideway in the carriage. This guideway prevents damage to the rolling element set while the carriage is separate from the guideway.The carriages are greased. > 2 3 Corrosion-resistant design...

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Miniature linear recirculating ball bearing and guideway assemblies (MAI 81)-10

Hole patterns of guideways The guideways have a symmetrical hole pattern (Figure 5 and Figure 6). With an asymmetrical hole pattern (customer request), the following must be adhered to: > a L j L RL = aa 1 a > L a > Lmin and a > R a > Rmin (Figure 5, Figure 6). Maximum number of pitches between holes The number of pitches between holes is the rounded whole number equivalent to:The distances a > a L j L RL aa () 2ַ a > 2 nl --------------------------------------------= > max Lmin j > L L and a > R are generally determined by:For guideways with a symmetrical hole pattern:Number of holes: a > 173...

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Miniature linear recirculating ball bearing and guideway assemblies (MAI 81)-11

Demands on the adjacent construction The design of the bearing arrangement is essentially deter-mined by the requirements for accuracy, rigidity and load carrying capacity of the bearing arrangement. This has a direct influence on the adjacent construction and primarily concerns: the geometrical and positional accuracy of the mounting surfaces > H Not convex(for all machined surfaces) Not convex(for all machined surfaces) the location of the guidance elements.Ensure that the adjacent construction has adequate strength. > AAA Geometrical and positional accuracy of the mounting surfaces Observe...

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