Maintenance-free linear axes for precise cutting testers - reliable measurement of cutting force

• What was needed: maintenance-free linear axes and guide systems made of high-performance plastics for precise movement in the test device for cutting tools.
• Requirements: smooth and repeatable linear movements, compact design, easy integration and long-term operation without maintenance.
• Industry: measuring and testing technology for cutting tools; quality assurance service.
• Success for the customer: reproducible movements and precise measurements of the cutting tools' sharpness permit reliable quality assurance. The lubrication-free components simplify integration and ensure a low-maintenance solution.

PWFT GmbH specialises in the precise sharpness testing of cutting tools, in particular razor blades. Well-known manufacturers all over the world rely on the company's test devices and services to ensure production quality. These test devices record the force curve during cutting down to the smallest irregularities, such as damage or burrs on the blade. An accurate and reproducible longitudinal movement is essential for simulating realistic conditions, measuring the degree of sharpness objectively and ensuring consistent quality for the entire length of the blade.

The challenge was to select components that could not only perform the required movement with high precision, but were also maintenance-free, durable and easy to integrate into the machine structure. Reliable, error-free operation is indispensable, especially in the case of automated test plans and complex measuring processes. PWFT was therefore looking for high-performance components that meet all these requirements at an affordable price.

The PWFT test devices carry out longitudinal movements made possible by maintenance-free linear axes with high-performance plastics. High helix lead screws from the dryspin product range ensure smooth and uniform movements of the test specimen. In addition to drylin low-profile and shaft guides, iglidur linear plain bearings with and without flange are used in various devices, where they impress with their good sliding properties and maintenance-free operation.

The drive unit consists of precise D7 or D8 stepper motors and control systems. They not only control the movement sequences, but also communicate with other drive components of the test device, which makes fully automated operation possible.

To realise individual designs and meet high requirements regarding sliding properties, PWFT also manufactures its own linear units, which are often based on customised 3D printing components. These parts are made from high-performance plastics and guarantee optimum performance even under demanding conditions.

In addition to the linear axes, PWFT uses articulated arm robots with systematised cutting movements in research projects to determine the influence of different chopping board materials on the durability of blades. Here, too, the force curve and process conditions are reliably measured, supported by lubrication-free guide systems and force sensor units.

The combination of maintenance-free components and innovative testing methods has proven its worth for PWFT: the devices allow for efficient quality assurance, reduce maintenance requirements and offer a decisive competitive advantage. These components are also regularly used by students who gain practical design experience at PWFT and thus create a close link between theory and practice.