Linear timing belt drives create motion in a straight line as opposed to power transmissions which operate in a rotary motion. A simple, non-motorized example of a linear drive would be the open/close mechanism of the window blinds in your home. However, we are referring to motorized linear belt drives that are used in manufacturing and mechanical applications.
In order to make your linear drive as efficient as possible we have outlined the 4 main components below. When these parts work flawlessly together you can achieve outstanding and highly-accurate performance.
Components to Consider when Designing a Linear Belt Drive
High precision timing belts the most crucial part of your belt drive and your starting point for proper functioning. Without precise timing, nothing else matters. Think of timing belts as the conductor in a belt drive symphony. Keeping perfect time coordinates all components and keeps the drive in sync. This is achieved through high-precision tooth design and strong tension members that help keep the belt stiff. Polyurethane timing belts with steel tension members are ideal in high speed applications (up to 80m/s) because of increased shear tooth strength and high-spring rate. For the stiffest timing belt, BRECOflex recommends the move-series.
Pulleys are mechanical devices that support the movement of a belt. In a linear drive, pulleys work with belts to move the belt in a forward or backward motion. In the case of timing belts, pulleys have matching teeth that mesh with the belts to create precise starting and stopping points.
Pulleys made of aluminum or stainless steel are the standard in most manufacturing applications. Variables within these two metal types are the width, pitch, number of teeth and whether pulley has flanges, self-tracking grooves and special modifications. BRECOflex can manufacture custom pulleys in-house for fast delivery
If you need to eliminate play between the pulley and the timing belt, choose a pulley with zero backlash.
Tensioners, also referred to a tension rollers can be toothed or smooth. They are used in applications where belt tensioning is required after installation in order to achieve proper pretensioning. Linear trolleys (moving omega drive) and linear tables (fixed omega drive) are two examples of the use of tensioners in a linear drive.
Tensioners can be made with our without eccentric adjustment and with our without flanges. A tensioner that is integrated with fastening holes and ball bearings will yield the most accurate tensioning and reliability.
Points to consider when choosing a tensioner are determining the correct width of the tensioner based on the tooth pitch, belt width and the center distance of the driving pulley.
Since open ended belts are made for linear motion rather than circular motion, clamps are required to hold each end of the timing belt in place and stabilize it as it moves via the belt drive. They are typically made from aluminum and there are several types offered. A general rule with clamps is to have at least five timing belt teeth in mesh for the most secure hold. Unlike ordinary clamps, tensioning clamps allow you to apply pretension to the belt after the belt is installed on the drive. For more assistance with pretension we recommend the SM5 Pre-Tension Meter.
When all of these components work together you get a highly efficient linear drive with long running performance. BRECOflex will work with you to find the best parts for your drive. You can save money in the long run and feel confident that you have partnered with a company that cares about