Medical Device Link.

Originally Published EMDM September 2003

Equipment News

Automation techniques facilitate assembly operations

A range of automation techniques are offered for microdispensing, microsoldering, and assembly operations in the medical industry. MTA Automation AG (Gals, Switzerland) specializes in microdispensing technology and has designed and installed more than 500 systems worldwide. The company’s systems are based on volumetric dispensing technology, which ensures repeatable dispensing regardless of the material’s viscosity. 

A recent application involved dispensing a monocomponent RTV silicone onto a pacemaker component, which was then joined with another part. A robot was used with a cleanroom conveyor and a tip-cleaning unit. After recentering the tip on a special device, the product was dispensed along a predefined path. The part was then picked up by a pneumatic device, turned over, and assembled with the other part. 

The firm also offers a patented mixing device suitable for use with small volumes of two-component products. The quality of the mix can be achieved by altering the mixing time and speed; three different mixing chamber sizes can be selected. The ratio can be programmed independently of the size of the dispensing unit. 

Dispensing system features vibratory operation

A dispenser for cyclohexanone and similar solvents is suitable for bonding medical components, mainly PVC tubes and connectors. Dosaset, offered by Tecna S.r.l. (Mirandola, MO, Italy), has a patented design based on a rotating and vibrating system. For each bonding cycle, the operator manually inserts a tube in the adapter. The dispenser recognizes the presence of the tube and starts the dispensing wheel vibration. A vibration adapter compensates for tolerances in the tube diameter, improving dispenser efficiency. 

Assembly dial delivers subsecond cycle times

An advanced assembly dial achieves cycle times of less than 1 second while offering the flexibility associated with servo drives. The Servochassis, supplied by ATS Automation Munich (Heimstetten, Germany), offers high throughput and easy configurability for the high-volume manufacture of medical products. 

“Most manufacturers recognize the capability of dedicated cam dials to offer faster index times than conventional assembly dials, despite their limited flexibility,” says Mike Cybulski, vice president systems operations, Eastern USA and Canada. The Servochassis features a simple design that is based on the same operating principle as a cam dial but uses direct-drive servo technology. “It is much faster than a conventional dial and offers operational flexibility beyond either technology,” he adds.

Configurable for four to 16 stations, the Servochassis incorporates high-precision, direct-drive servomotors that drive two independent axes. The tooling for all stations is mounted on the dial top plate and is raised and lowered simultaneously along a single z-axis. The motion can be finely tuned to allow all tooling to clear the table in the shortest possible time prior to indexing. A second servomotor, mounted underneath the dial plate, indexes the table. Individual tooling operations are pneumatically driven at each station. 

Fluid-dispensing system increases yields

A precision dispensing system applies accurate and consistent amounts of solder paste, flux, adhesives, epoxies, and other fluids used in electronics assembly processes. The Ultra 2400 dispensing workstation, available from EFD International Inc. (Dunstable, Beds, UK), offers simultaneous digital display of dispense time and mode, air pressure, vacuum, and shot count. Standard features include automatic voltage regulation from 85 to 265 V with universal power plugs, an internal pressure reservoir that minimizes cycle time and ensures deposit control, and security lockout with tamperproof password control. 

Several accessories are available to customize the Ultra 2400 workstation for different applications and to enhance productivity. Options include a flexible task light, a magnifier for precision closeup work, a flexible syringe barrel holder, and an ergonomic barrel grip with a touch-sensor finger switch. 

Subcontractor develops cleanroom assembly equipment

A contract manufacturer designs and builds automated equipment for the manufacture of medical devices, which can then be run in the company’s Class 100,000 cleanroom. This arrangement enables Integrated BioSciences Inc. (IBS; Harrisburg, PA, USA) to combine traditional manufacturing and automation to maintain high quality and low costs. 

The company’s design teams analyze the customer’s product to determine the type of equipment that is required for a given application. Systems range from benchtop fixtures and tooling to fully automatic assembly lines. Contract manufacturing capabilities range from device design support through assembly, packaging, and final sterilization. 

Modular UV curing system provides versatility 

A UV and visible-light spot-curing platform provides versatility in a cost-effective system. The OmniCure Series 1000, developed by EXFO Photonic Solutions Inc. (Mississauga, ON, Canada), is suitable for manual applications, and contains many features typically found only in higher-priced units. “The Series 1000 will address customers who don’t necessarily need a full-fledged system for their manual assembly applications,” says Allan Firhoj, general manager of EXFO’s Photonics and Life Sciences division. 

The system includes a powerful 100-W bulb with 2000 hours of lamp life. A manual iris can be adjusted by 1% increments to focus the light output. The OmniCure Series 1000 also contains the company’s patented Intelli-Lamp technology to maintain optimum lamp conditions and a stable output. A built-in timer, process alarms, selectable bandpass filters, and password protection ensure process control. Other features include finger-touch controls, a bright-blue LED, process indicators, and automatic lamp striking. 

Cutting machine incorporates solvent-dispensing system

A benchtop programmable cutting machine is suitable for the assembly of medical-grade tubing. READYcut, provided by Tecnoideal S.r.l. (Mirandola, MO, Italy), incorporates a system for solvent dispensing on the tube end. The tubing, cut and wet, is released to the operator’s hand for immediate assembly. The system is particularly suitable for the manufacture of medical tubing sets, where length precision, accuracy of the cut, and the quality of solvent dispensing are critical. 

The cutter is supplied with a motorized uncoiler that precisely controls the uncoiling process. This feature is useful in applications that involve elastomeric tubing such as latex or silicone, or where there is inconsistent uniformity in the coiled tubing. The motorized uncoiler minimizes tube stretching or pulling, guaranteeing consistent cut length. 

The company supplies a range of assembly and testing equipment.

Transport system moves sensitive products

A monorail transport system utilizes self-propelled shuttles to efficiently transport parts. The Montrac system, offered by Montech AG (Derendingen, Switzerland), features impact- and shock-free shuttle movement, ensuring the safe handling of sensitive products and liquids. 

Each shuttle, electrically driven on the track, is specially designed with preset acceleration and deceleration ramps and optical sensors. This ensures gradual acceleration, shock-free transport, and smooth braking. Because of the drive design of the system, Montrac meets the criteria for cleanroom conditions. 

Copyright ©2004 European Medical Device Manufacturer