Medical Device Link.

EQUIPMENT UPDATE

NC programming software is optimised for laser cutting

The latest version of a numerical control (NC) programming software package includes optimised functions developed especially for laser cutting in such applications as tube and stent manufacturing. The advances in Cagila Version 3 from CAM-Service GmbH (Herford, Germany; www.cam-service.com) improve data preparation for NC-based microprocessing. They include the Part Wizard, a drag-and-drop interface that facilitates the combining of basic objects into complex parametric designs and enables complete part families to be generated and modified in seconds. Also new is a module for simultaneous four-axis processing that was designed particularly for tube cutting.

Another new feature is an analyser that optimises the exchange of information between the computer-aided manufacturing system and a machine’s NC control. A multisegment technology feature introduced with this version of the software allows the segmentation and partial processing of contours with multiple lead-ins and lead-outs. This tool minimises the effect of thermal and mechanical deformations on complex tube geometries during cutting. Finally, the new software release includes an updated high-performance nesting module.

Tube cutter retains tight length accuracy at high line speeds

Available in an updated version, a cleanroom-capable rotary tube cutter specifically designed for producing bubble, taper and bump tubing for medical device applications employs state-of-the-art ac brushless servomotors with a fully digital three-axis control system. Gillard Cutting Technology (Tewkesbury, Glos, UK; www.gillard.co.uk) engineered the high-performance Servo-Torq Ultra system to hold length accuracies within ±0.1 mm even at very high line speeds. Both caterpillar infeed belts have ac servo drives, which are synchronised to within one encoder pulse per motor revolution to produce a speed-holding accuracy better than 0.0005%. A third servomotor powers the system’s rotary cutting blade.

All motors are monitored by a single motion controller running on a digital communication network. The control system allows precision adjustment of line-speed acceleration and deceleration during creation of bubbles along the tube length. Air blowing, clamping, cut position and minimum and maximum outside tube diameter are all controllable via a colour touch screen. In addition, the manufacturer has moved the caterpillar much nearer the knife blade, improving the handling of ultra-small-diameter tubing down to 0.3 mm OD.

Automatic unit cuts flexible tubing at nine feed rates

An automatic tube cutter is designed to cut flexible tubing, sleeving and similar material to a programmed length easily and accurately. Also programmable in terms of the number of cut pieces, the Model WC601B rotary-blade tubing cutter from Eraser Company, Inc. (Syracuse, NY, USA; www.eraser.com), features a choice of nine variable feed rates, which enables the operator to choose the optimal rate for a given material in order to maximise both production throughput and the accuracy and repeatability of the cut length.

The unit can process flexible tubing to very tight specifications. Combining an adjustable dual-drive belt feed and a rotary cutting head with a stepper-motor drive system, the cutter achieves results equivalent to those of hand-operated machines. The belt feed and rotary cutter ensure that processed material is not crushed either at the cut ends or along its length. A batching feature allows for preprogramming of all variables for frequently run jobs, while a kitting feature makes possible the cutting of multiple pieces or different lengths within a batch.

Laser marking platform offers versatility

A laser marking system offers medical device manufacturers a configurable technology suitable for marking applications both on the production line and in the laboratory. Developed by Rofin/Baasel Lasertech (Starnberg, Germany; www.rofin.com), the Cube is a platform for the integration of various laser sources, including solid-state, fibre and diode lasers, with an array of available focusing optics and axes in any configuration desired. Users can permanently mark parts made from many different types of materials with alphanumeric text, vector or rastered graphics, gray-scale images, bar codes and Data Matrix codes.

The laser marking system’s flexible configurability offers options for use. Fitted with a galvanic scanning head and servo-driven positioning axes, it can mark, quickly and precisely, either large parts or smaller parts in large trays. The workstation incorporates automatic rise-and-fall doors that facilitate robotic loading and unloading. Alternatively, it can be employed as a stand-alone system loaded and unloaded manually via the automatic doors.

Horizontal catheter tester simulates actual applications

A fully automated testing machine for complete catheters and component parts is oriented horizontally in order to achieve more realistic results than can be acquired with standard vertical test apparatus. In developing the system, Zwick GmbH & Co. (Ulm, Germany; www.zwick.com) combined its high-resolution testControl hardware with testXpert software that controls the machine’s crosshead and special automated pneumatic grips. The design ensures that forces measured originate only from the sample under test and not the machine. The machine pushes the catheter through a tortuous path of selectable size either bit by bit or in a continuous movement.

The software calculates the track force of the catheter, interventional device or guidewire under test, along with its push efficiency, insertion force, guidewire movement force and catheter tip flexibility. In addition, it measures lubricious guidewire and catheter track force, comparing the data acquired with a coated device with data from the original track test to determine whether coatings affect track force in a particular application. The system can position the machine crosshead within 1 µm and produce readings more accurate than 0.5% at forces down to 0.1 mN or less.