To convey means to move. Small parts pose special challenges here, as, statistically, they are more prone to “go astray” than large objects. For smooth production, however, it is essential that nothing gets jammed in the conveyor belt. To avoid such malfunctions and, at the same time, enable easy and fast integration in existing or new systems, the company Vetter Kleinförderbänder GmbH, located in the Swabian town of Westerstetten near Ulm, developed encapsulated conveyor belts. All key components of the conveyor belt are completely enclosed, with a smooth outer surface, and are almost completely covered by the actual belt. Because the drives are integrated, this means that only usable area remains without any bulky (drive) attachments. A cleverly designed modular structure makes assembly much easier, and even variants for special requirements can be supplied on a practically ready-to-use basis.
The small conveyor belts are powerful at low current consumption and function very reliably even in 3-shift operation. The well-designed construction with no interfering contours in the series with internal and transverse drive integrates easily in a wide range of systems. As a result, typical application areas are very diverse and range from mechanical engineering and microtechnology to the pharmaceutical and food industries or image processing. Thanks to the low voltage of just 24 V, no special protective measures are necessary.
The basis for the wide field of applications is the cleverly-designed modular concept: serving as the foundation are the conveyor belts, which are available in various widths and transport lengths. With the small parts conveyor belts, the idler roller for the conveyor belt is connected to an aluminium-section “supporting element” that can be cut to the required individual length. The movement is provided by another module comprising a microdrive and a drive roller on the other side of the supporting element. If the supporting element (which is only needed for the variable length) is omitted, even short conveyor units measuring 200 mm in length can be realised with a height of just 30 mm and a width of 60 mm – and that without any interfering contours.
This type of construction can only be achieved by using extremely compact drives that are much narrower than the diameter of the drive- or idler rollers. Vetter therefore uses microdrives from the product line of drive specialist FAULHABER. Depending on the conveyor design, small, precious-metal commutated DC drives with 8 mm diameter or brushless, i.e., electronically commutated DC drives with diameters of 16, 22 or 32 mm and integrated speed controllers are installed. Various belt speeds are possible as a result. The speed of the motors can be controlled with very sensitive adjustment and is infinitely variable.
The microdrives come as a pre-assembled unit, each with the appropriate long-life planetary gearheads. The drives can easily be installed in the standard conveyor belts, which, depending on the version, are 12, 20, 30 or 40 mm tall and 20, 40, 60 or 80 mm wide. The 40 mm tall variants are also available with housings that are 120, 160 or 200 mm wide. Special solutions based on the same principle, such as ascending conveyors, are also available. Moreover, variable sizes and lengths can be produced quickly thanks to the modular concept. All moving parts of the conveyor belts and of the drives are completely enclosed and provided with lifetimelubrication, thus making them maintenance free.
The reliability of a conveyor belt is largely determined by the drive. Microdrives obey their own rules, however. With its many years of experience, FAULHABER is able to supply drive units that are optimised down to the last detail. Not only have the motors proven their reliability in a wide range of applications but the used gearheads as well. Especially with microdrives, the special design is essential for a long service life. High input speeds and high output torque place special demands on materials, tooth geometry, bearings and – above all – on the lubricant. Properly dimensioned, these drives are then suitable for many years of maintenance-free use. In the small parts conveyor belts, they have once again proven their reliability.