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Articles from 2004 In January

Recent Advances in Molding Technology

Originally Published MPMN January 2004


Recent Advances in Molding Technology
By eliminating the manual assembly of syringe plungers, a molding process developed by Boucherie USA Inc. reduces the products' exposure to contaminants.

To stay competitive, suppliers of molding services and equipment have learned to keep their eyes glued to the bottom line. Several companies that have found novel ways to optimize processes and compress costs are profiled in this section. For example, one firm has developed a two-component mold for syringe plungers, thus eliminating assembly operations. Metal-injection molding is touted by another company as a time-saving technique for the high-volume production of intricate metal components. On the equipment and tooling front, a continuous vacuum forming system is described as a desirable alternative to blow molding machines, while cavity pressure sensors, argues another supplier, should be part of every molder's toolbox. And speaking of tools, if you're in the market for molding services, you will find yet one more indispensable resource on page 66: MPMN's Molding Services Buyers Guide.

Two-Component Mold Eliminates Syringe-Plunger Assembly Operations

A two-component mold that fabricates syringe plungers does away with the need to assemble the bodies and the tips. The tips are molded first, after which they are transferred to plunger-body mold cavities. Each cycle produces complete plungers, thus reducing contamination concerns. Mold and die maker Boucherie USA Inc. has a patent pending for the process.

"The part is never cleaner than when it falls from the mold," says John C. Williams, manager of the company's plastic technology business unit. "By eliminating a step in the assembly process, we have reduced the products' exposure to contaminants."

The absence of visible injection points and parting lines is cited as another benefit of the process. It also creates a permanent bond between the plunger tip and syringe body. In addition, says Williams, "we can achieve very fast cycle times . . . in some cases under 7.5 seconds."

The plunger tips are made from Santoprene TPE 8281-55 from Advanced Elastomer Systems. The material complies with ISO 10993 and USP Class VI guidelines, is latex free, and is compatible with most forms of sterilization. Its compression set ensures reliable sealability, and it withstands exposure to a range of temperatures.

Boucherie also recently announced that it has developed a Shuttle Mold that, it says, may have medical product applications. An external station cools the first-shot molded parts, shuttles them to the overmolding cavities, and removes the finished part.

The molds are typically designed in a stack configuration. This enables the use of high-cavitation molds with a standard clamp and small press. Because it allows for short cycle times, the Shuttle Mold is suited for high-volume production processes, according to the firm.

Metal-Injection Molding Touted as Alternative to Small Parts Machining

A company that provides metal-injection molding (MIM) services describes the technology as a cost-effective alternative to machining. Parts can be manufactured in 15 to 20 seconds by means of MIM compared with the 15 to 20 minutes that machining might require, according to Morgan Advanced Ceramics. The technique is suited for the high-volume production of intricate metal components. Laparoscopic instruments are among the products that would benefit from this method.

Metal-injection molding is suited for the high-volume production of intricate metal components, according to Morgan Advanced Ceramics.

MIM is defined as a net-shaping process in which a fine metal powder, typically smaller than 20 µm, is mixed with a binder system to create feedstock. Common binders are a combination of waxes and organic materials, which may include thermoplastics or thermosets along with surfactants and other additives. The feedstock is injected into a mold cavity using molding machines that are very similar to traditional plastic-injection molders. Most of the binder is removed by means of a thermochemical process. The parts are then placed in a sintering furnace, where any remaining binder is removed and the parts are sintered to their final dimensions. The end result is a near-net-shape part with a typical density of 98%. Depending on the part, this can be the final step, or secondary operations can be performed.

MIM parts can be comparable in strength to parts machined from wrought metal. They can be created with complex features such as cross-drilled holes, undercuts, and fins, and generally do not require secondary machining. In most cases, several parts of an assembly can be molded simultaneously.

The technique also provides a cost advantage for the production of custom components, according to Morgan Advanced Ceramics. MIM allows for the development of specific blends to suit specific customer applications.

The MIM process is described in a Metal Injection Molding Design Guide that can be downloaded in a pdf format at

Vacuum Forming System Introduced

An alternative to blow molding technology, a continuous vacuum forming (CVF) system can be used in vertical and horizontal format for both low- and high-volume production. The system, which was recently introduced by HPM Div., Taylor's Industrial Services LLC, minimizes the number of components and holds down production costs.

"In CVF systems, the resin is pulled to the outer mold wall instead of being pushed there by internal pressure," explains product manager Chris Turner. Several complete molds are arranged in a contiguous loop. The molds move continuously, capturing the resin. This technique reduces process variability, adds Turner, and allows the use of low-viscosity resins. Because of the continuous movement and end-to-end tooling design, flash and pinch scrap is reduced, thereby reducing processing costs.

Lifter systems distributed by D-M-E Co. enable deeper undercuts in plastic molds than were previously possible.

The CVF system can incorporate interchangeable molds for fast product changeovers. It requires neither hydraulic fluid nor water for mold cooling.

The equipment is a "perfect fit for niche markets," according to Turner, including the medical device sector. "It significantly improves the return on investment because of the process cost savings. The CVF system has a higher efficiency conversion rate of pellets to the finished part, enabling molders to expand applications and to be more competitive."

Lifters Boost Undercut Capabilities

A lifter system that is actuated from a slide rather than a static base in the ejector plate offers OEMs and mold makers increased flexibility. The VectorForm Lifter System, developed by Takao Injection Mold Engineering and distributed by D-M-E Co., allows application designers to incorporate undercuts that are twice as deep as were previously possible. Alternatively, mold designers can cut ejector strokes in half if they choose to maintain existing undercut geometries.

Mold cavity pressure sensors from Priamus 
Systems Technologies LLC are designed to 
monitor and optimize injection molding 

Whereas most lifter systems recommend a maximum angle of 15°, VectorForm can accommodate angles greater than 30° because of the sliding base. Multiple lifter cores can be integrated into a single system, thus eliminating the need for separate lifters when processing parts with multiple undercuts in the same line of draw. Actuating multiple lifter cores with a single system results in significant savings in cost and space within the mold. Small housings and enclosures are among the products that would benefit.

A design guide that provides application examples and detailed design and installation guidelines is available from the company.

Temperature Sensor Optimizes Molding Process

Pressure and temperature both have an influence on the injection molding process. While cavity pressure measurement is a widespread practice, cavity temperature measurements often are not part of a molder's standard operating procedures, according to Priamus Systems Technologies LLC. Yet they can yield substantial benefits, according to the firm.

Priamus has developed a cavity temperature sensor that is attached to a flexible connecting cable. The sensor housing measures 12.5 mm long and only 1 mm diam. The compact construction makes it compatible with small moldings and accelerates readings.

Placed at the end of the fill, the sensor's signal can actuate automatic switchovers to holding pressure. Unlike conventional switchover methods, this process can respond to variations in viscosity.

Sequential molding applications can be controlled by placing a temperature sensor at each gate. As soon as the melt reaches the sensor, it sends a digital signal to the controller, which opens or closes the valve gate depending on the position of the melt.

Copyright ©2004 Medical Product Manufacturing News


Originally Published MPMN January 2004

Outsourcing Outlook


Chassis Prototype Reduces Downstream Manufacturing Costs

A manufacturer of precision enclosures developed a prototype for the sheet-metal chassis of an ultrasound machine that improved efficiency and reduced downstream manufacturing costs. Design innovations resulting from the prototype process included the use of a preplated material secured with small, nondeforming fuse welds, eliminating secondary brackets and fasteners. In addition, it was discovered that smaller components could be formed from scrap generated during the production of larger chassis pieces. Prototype work is done in the company's secured Allenton, WI site, which incorporates the same systems and equipment used in its manufacturing plants. Maysteel, Menomonee Falls, WI; 

Turnkey Development Available for Single-Use Devices

An outsource provider of sterile, single-use medical devices offers complete product life-cycle management. In addition to proof-of-concept testing, the company's services include initial development, production, supply chain management, and product improvement. The company uses its in-house CAD and stereolithography systems for rapid prototype production; stereolithography apparatus models can be produced within a few hours. Avail, Fort Worth, TX; 

Metal Fabricator Manufactures Prototype of Parabolic Reflector

Custom, precision sheet-metal fabrication and machining services are available from a manufacturer of OEM medical device components. Capabilities range from prototyping to full-production quantities, custom fabrication, machining, chemical processing, engraving, and assembly. Previously manufactured prototypes for initial testing and calibration include a parabolic reflector made from a 1¼32-in.-thick, high-reflectivity aluminum sheet. The reflector is used in infant-care radiant-warmer applications in hospitals. Electromet Corp., Hagerstown, MD; 

Contract Manufacturer Adds Prototyping Department

A contract manufacturer has added a dedicated prototyping department to its in-house CNC milling and turning capabilities. With a lead time of two weeks or less, the company performs laser marking, heat-treating, turning, microhole drilling, fine threading, slotting, fine deburring and polishing, and other finishing operations. Specialty materials include titanium, platinum, stainless steel, plastics, and metals. Specialized Medical Devices, Lancaster, PA; 

Biomedical Company Emphasizes Prototype Design for Manufacturability

A company offers full prototyping capabilities in addition to precision machining, fabricating, and finishing services. The company's engineering experience can be applied to improving an existing tool or developing a custom instrument. The latest 3-D CAD software is available for use. Gauthier Biomedical, Grafton, WI; 

Micromachining Capability Produces Wire Prototypes

Prototypes of high-tolerance miniature medical devices are produced from nitinol, stainless steel, and platinum iridium wire stock, using a centerless and OD grinding machine. The CAM SXE technology OD grinds shapes such as flats, tapers, balls, and threads, and the centerless process is applied to single- or multitapered wires. Multiple shapes are placed on the same guidewire. Reading data from CAD drawings, high-precision servomotors control the grinding of the wires automatically, producing diameters as small as 0.0005 in. Wires are ground with a diameter tolerance as close as 0.0001 in., a length tolerance within 0.002 in., and a surface finish of 9 Ra or higher. Glebar Company, Inc., Franklin Lakes, NJ; 

Plastic and Metal Manufacturing Services Include Prototyping

With facilities in Ireland and the United States, a company includes prototyping among its complete design, development, and contract manufacturing services. Devices in the conceptual stage undergo prototyping and finite-element, risk, and value analyses before the design and development phases. Capabilities include hypotubes, stents, balloons, extrusions, and medical device assemblies, with specialties in minimally invasive devices and metal and polymer components. 
Creganna Medical Devices, Livermore, CA; 

Precision Prototyping Uses CNC Tooling to Develop 3-D Parts

A company that provides precision prototyping services focuses on original methods for product validation and testing, providing visual models, engineering breadboard concepts, and functional preproduction prototypes. Capabilities include advanced rapid prototyping techniques with an emphasis on CNC tooling for the development of 3-D parts. Additional modeling services complement the company's model-building strategies. Herbst LaZar Bell Inc., Chicago, IL; 

Fabrication Services Satisfy Prototyping Requirements

A company that machines and fabricates medical device assemblies, instruments, and implant components also provides prototyping services. In addition to design assistance and value engineering, the company offers single-part or assembly fabrication services to satisfy prototype-engineering requirements. 3D Machining Inc., Riviera Beach, FL; 

Insert Molding Prototypes Offered for Critical-Tolerance Devices

A manufacturer offers specialty 
insert molding prototype services for medical devices, components, and subassemblies. The company also provides customers with part design assistance, materials recommendations, and molded samples as a prelude to full-scale production. In addition to vertical clamp and vertical injection molding presses, book mold tooling is also used to secure delicate inserts in place. Needles, catheters, medical cables, and implantables requiring critical tolerances are routinely produced. Aberdeen Technologies Inc., Carol Stream, IL; 

Copyright ©2004 Medical Product Manufacturing News

Testing and Inspection Equipment and Services

Originally Published MPMN January 2004


Testing and Inspection Equipment and Services

Multipurpose tester

Compact production equipment capable of performing up to 65 steps can be configured to meet the requirements of a range of products. Functions include feeding, assembly, printing, ultrasonic welding, labeling, leak testing, and checking of printing patterns, dosage, and more. The single system also measures tension, pressure, force, and velocity. The equipment is made from stainless steel and is designed for easy access and disinfection. Mueller + Kurtz Sondermaschinen GmbH, Winterbach, Germany; 

Implanted device testing

Testing and evaluation equipment allows hard implants, such as metallic stents, to be analyzed within surrounding tissue. While the evaluation of implants usually requires decalcifying the bone or removing the device, the Exakt Histological Processing System enables viewing of the soft or hard implant within the hard tissue. Photographs suitable for regulatory agency submissions and medical publishing can be generated by the system. NAMSA, Northwood, OH; 

Syringe tester

The force required to move a syringe plunger is measured using a hypodermic syringe tester. The Lab Master can also measure the penetration resistance of the tip with 0.01-lbf resolution. Users can evaluate the properties of tips for R&D purposes, or use the instrument for production testing. A fixture supports the syringe and other probe options, allowing the machine to be configured for R&D analysis or one-touch automated process control. The Lab Master includes a Windows operating system and a touch screen flat-panel display in a compact unit. Force measurement range and resolution achieves 250 ¥ 0.01 lbf, and the device's measurement accuracy is ±0.25 lbf or 0.5% of reading. Control accuracy is ±0.34 lbf steady state. The system also offers a position range and resolution of 60 mm ¥ 0.1 µm, and measurement accuracy of ±1.0 µm/60 mm. Testing Machines Inc., Ronkonkoma, NY; 

Chemical and biological analysis

A testing laboratory provides chemical and microbiological analytical services. Its offerings include plastic- and glass-container testing, comparator product testing, extractables and leachates analysis, consulting services, and analytical-method development and validation. The microbiology testing covers nonsterile products and sterile products using barrier isolator technology. Lancaster Laboratories, Lancaster, PA; 

Pinhole detector

Featuring a curtain sensor and control unit, an electronic pinhole detector locates defects in laminated fabrics and plastic and polyurethane sheet, film, and bags on the production line. According to the company, the PDC-20 in-line equipment is an alternative to in-line optical or visual inspection, which yields high scrap levels. When faulty material passes through the curtain sensor, the detection circuit records defect data and provides various process control outputs to activate external alarms, lights, and auxiliary machinery. Tetrafluoroethylene, PVC, and other materials in thicknesses of 0.001 to 0.100 in. and widths to 144 in. can be tested. The equipment is also available in modified designs to accommodate the testing of tubing and discrete parts. Clinton Instrument Co., Clinton, CT; 

Defibrillator analyzers

Defibrillator analyzers incorporate a large graphic display with a menu interface for easy access to all tests. The DA-2003, without pacing capabilities, provides the features of a basic defibrillator analyzer and the DA-2003P, with pacing, adds transthoracic pace-testing capabilities. The DA-2003 measures delivered energy in watt-seconds with a simulated human resistance of 50 W; the defibrillator pulse can be replayed for viewing on a recorder or oscilloscope. The DA-2003P includes the same features, with the addition of tests and displays of pulse rate and width, current, voltage, and refractory periods. Pacer loads from 50 to 2300 W are built in. BC Group, St. Louis, MO; 

Inspection services

A one-stop provider of testing and inspection services for the analytical and diagnostic industry applies comprehensive tests during the instrument assembly process. Run-in tests designed for each instrument prevent breakdowns and failures during the start-up phase at the customer's site. Specialists in the company's medical lab facility perform tests under ambient lab working conditions. The company also develops custom test procedures and instruments for a range of OEM mechanical and electronic applications. BIT Analytical Instruments, Menomonee Falls, WI; 

Universal test machine

An accuracy-testing machine enables customers to choose capabilities for research and product quality assessment. The LFPlus accepts XLC-series load cells or Chatillon digital force gauges as the load-measuring device. It also features a generous working space to accommodate larger-than-average samples. The company markets specialty material-testing equipment and manufactures electrical and electromechanical products. Ametek, Largo, FL; 

Multimode manifold

When attached to a hydraulic burst and leak tester, a manifold enables the unattended testing of one to 10 parts simultaneously. Featuring three basic modes, the Smart manifold's parallel mode pressurizes all selected ports simultaneously. Failed ports are automatically detected and closed before testing is resumed. The sequential mode pressurizes each selected port individually, suitable for pressure fluctuations. The single mode affects only the selected individual port, allowing the tester to be used for single-product testing without disconnection from the Smart manifold. Crescent Design, San Diego, CA; 

Copyright ©2004 Medical Product Manufacturing News

Switches, Signals, and Connectors

Originally Published MPMN January 2004


Switches, Signals, and Connectors

Slide components

Available in surface-mount or through-hole versions, compact slide switches feature double-pole capabilities in a single-pole body. The Alcoswitch units can be ordered unsealed or with an IP67-rated seal. With printed circuit board retention features and a robust actuator, the components offer repeatable performance for up to 10,000 cycles. The contacts within the switches are rated for 0.4 VA at 20 V dc with an initial contact resistance of less than 50 mW. The contacts are phosphor bronze with gold over nickel plating, and offer actuation force ranges from 70 to 500 g. Tyco Electronics, Harrisburg, PA; 

Miniature switches

A line of miniature and subminiature PC-mount and sealed switches includes rocker, toggle, push-button, and slide options. Many of the components are also available for surface-mount applications, are sealed to an IP67 rating, and are UL/CUL certified. A catalog of the miniature switches is available, detailing product features and specifications. Carling Technologies Inc., Plainville, CT; 

Motion switches

Miniature switches sense motion, acceleration, impact, and other disturbances. Their current-handling capacity ranges from milliamps to amps, and sensitivity ranges from fractional to several thousand forces of gravity. Multiple configurations are available, and the switches can be oriented for linear, angular, or hemispherical sensing. Hermetically sealed 
for long life and reliability, the components are easily mounted to printed circuit boards. 
Aerodyne Controls, Ronkonkoma, NY; 

Key switches

Key switches are available in a range of models and sizes, and with various options. They offer vibration resistance and guaranteed switching. The K6 and K12 models' switching voltage ranges from 2 to 30 V dc, and their switching currents range from 10 µA to 100 mA dc. The K12 series features standard travel lengths of 1.0, 1.5, and 2.0 mm, and a service life in excess of one million cycles. A special contact system enables the button travel, tactile snap point, and operating force to be engineered to custom applications. The K6 switches offer travel lengths from 1 to 1.5 mm, and are available in four versions, with and without an LED. With a smaller footprint than earlier versions, the components require a printed circuit board space of 10.9 ¥ 7.4 ¥ 8.4 mm. The life span of the K6 models exceeds 200,000 cycles. ITT Industries, Cannon, Newton, MA; 

Hybrid connectors

Mixing multipurpose contacts in one connector body provides design flexibility. The contacts can be assembled into a variety of configurations. With more than eight standard bodies to choose from, capabilities include fiber-optic, fluid or gas, high-voltage, and high-current options. The hybrid line can be optionally sealed to an IP68 rating; a number of options and accessories are available. Fischer Connectors, Alpharetta, GA; 

PCB terminal block

A high-power printed circuit board (PCB) terminal block is based on screw-clamp technology. The MKDSP 25 enables the connection of large conductors directly to the PCB, typically found in ring-tongue and panel-mount applications. The component is available in a single position or preassembled in two to nine positions. In addition to offering screw-mounting flanges to the PCB, the terminal block has a current capacity of up to 125 A at 600 V, and accepts #20 2 AWG wire. 
Phoenix Contact Inc., Harrisburg, PA; 

Sensor arc

A device with a curved, one-piece, flexible sensing edge provides contact closure when touched at any point. Sensor-Ring is suitable for medical scanning heads, and replaces multipiece, multiswitch components. The sensing edge is located on the circumference of a hollow arc or ring, enabling the pass-through of wires, mechanical components, or personnel. Available in diameters of 1.5-5 ft, the component covers an angular range from 10° to 360°. The connection is made with a stainless-steel armored cable, and sensors can be installed on up to three sides of the ring. Classified with an IP67 rating, the switch is protected against dust and immersion. Tapeswitch Corp., Farmingdale, NY; 

I/O connector

A microcircular connector has been developed in response to the growing need for ruggedness in medical equipment. Designed for use in harsh environments, the JB5 series offers waterproof sealing with an IP68 rating and a secure push-pull mating system. With solder terminals and a lightweight aluminum alloy shell, the connector is available with from 2 to 25 contacts. Each contact features a current rating of 2 A, a 200-V-ac dielectric withstanding voltage, and a temperature range of -55° to 85°C. 
JAE Electronics Inc., Irvine, CA; 

Terminal blocks

Compact sensor or terminal blocks are suitable for control panels or junction boxes with limited space and persistent vibration. Front-entry wiring of the 270 series facilitates assembly, and the company's Cage Clamp for conductors ensures a vibration-proof connection. The jumper system with slots to accommodate noninsulated push-in jumper bars protects against accidental contact. Jumpers are available in 2- through 17-way versions for power distribution. An optional LED indicates the status of and locations for marker cards to ensure secure connections. Wago, Germantown, WI; 

Emergency stops

Panel-mounted switches are available in twist-to-release and key-to-release options for emergency-stop operations. The 04, 61, and 44 series of the EN 418 E-Stops are designed with a mechanism to prevent the switch contacts from operating if the mushroom head is not fully actuated. The 22.5-mm mounted 04 and 44 switches have 37-mm-diam actuators. The 04 model incorporates a bayonet-fitting contact block with two mounting screws, while the 44 series has a snap-on contact block. Installed using a threaded shaft and lock nut, the 61 model measures 16 mm with a 27-mm-diam actuator. Accessories include emergency-stop labels and enclosure boxes.EAO, Milford, CT; 

Copyright ©2004 Medical Product Manufacturing News

Copolyester Is Clear Choice for Safety Syringe

Originally Published MPMN January 2004


Copolyester Is Clear Choice for Safety Syringe

The material's tribological properties enhance product's passive activation design

Rita Emmanouilidou

The UltraSafe passive delivery system protects healthcare practitioners from accidental needle sticks. The device's inner body is made from Eastar copolyester DN003, a material with minimal friction that offers the strength and clarity of polycarbonate.

The advent of needle-safety devices received a boost in 2000 with the enactment of the OSHA Needle Stick Safety and Prevention Act. Safety Syringes Inc. (SSI; Carlsbad, CA; was ahead of the curve when it introduced the manually activated Ultrasafe Needle Guard in 1999. It recently introduced a passively activated design. In developing its newest product, the company sought a combination of enhanced safety and aesthetics. The use of Eastar copolyester DN003 from Eastman Chemical Co. (Kingsport, TN; has helped the firm to achieve its goal.

The UltraSafe passive delivery system comprises two molded components: the outer guard, which shields the user from accidental needle sticks, and the inner body. The outer guard has a grip that is automatically activated after injection. "When the plunger bottoms out, the syringe slides back into the body of the device," says Erik Miller, SSI director of marketing. "The needle is then covered by the guard portion of the device." 

During the design phase, the company determined that the outer guard had to have the same look and feel as the inner body. To reduce friction and ensure the timely release of the protective guard, however, each component had to be molded from a different material. Polycarbonate (PC) was selected for the outer guard. The remaining challenge was to find a material for the inner body that had the strength and clarity of polycarbonate while minimizing friction.

Eastar copolyester DN003 fit the bill. The material did not cause undue friction, and it provided the mechanical functionality required to activate the safety device. DN003 resists chemicals and can withstand most sterilization methods. Additionally, it processes similarly to polycarbonate, saving SSI the expense of potential mold modifications and added production costs. "There were no negatives to making the change," says Tom Hall, SSI's regulatory affairs and quality assurance director. "DN003 was virtually a drop-in replacement. The form and function of the part stayed the same."

Eastar copolyesters are suited for a range of medical applications. The materials are durable, withstanding stress and impact. Because of their ductility, they can be used in snap-fit assemblies, thus eliminating solvent bonding. They can be extruded and injection or blow molded, and are available in water-clear or colored formulations. Customers can select the material with only those properties required for their medical product application.

SSI's UltraSafe passive delivery systems can accommodate a broad range of syringe sizes and staked or luer lock/slip needle configurations. They are suitable for use with drugs that come in prefilled glass syringes.

Copyright ©2004 Medical Product Manufacturing News

Low-Inertia Motors Move Forward Biomedical Imaging Technology

Originally Published MPMN January 2004


Low-Inertia Motors Move Forward Biomedical Imaging Technology

Rapid 1-mm x-y movements are accurate to within 1 µm

Rita Emmanouilidou
Two motors form an x-y stage that provides fast, repetitive, high-accuracy positioning of glass slides for white 
blood cell-imaging.

Traditional instruments for positioning slides, test tubes, and microarrays have depended on leadscrew mechanisms. However, such devices are subject to friction and rotational inertia, which makes it difficult to meet OEM demands for high throughput. Low-inertia, direct-drive Micro Linear motors are a better alternative for precise, repetitive, short-distance positioning applications, according to Copley Controls (Canton, MA). The company's motors currently are 
used in blood cell- imaging devices.

The motors' tubular polymer construction is designed with a 0.016-in. symmetrical air gap between the fixed and moving parts. This helps to lessen friction and wear. The units are available with a peak force from 19 to 45 N and continuous force from 3.1 to 8.7 N; they achieve a 15-25-m/sec2 peak acceleration range and 3-m/sec velocity. The thrust rods, which measure 11 mm in diameter, can be specified in 62-510-mm lengths. Forcers that encapsulate the drive coils are available in lengths of 36-113 mm. They measure 34 mm wide and 25 mm in height. 

In the blood cell-imaging device, two Micro linear motors form an x and y stage that positions blood-coated slides under a camera lens. The equipment captures images of white blood cells that measure 10-25 µm in diameter. Positioning accuracy in this application is 1 µm. As many as 200 blood cell images can be captured from a few square centimeters of slide surface. The motors complete repetitive 1-mm x-y movements at1-µm accuracy within 25 milliseconds.

Copley Controls
20 Dan Rd.
Canton, MA 02021
tel: 781/828-8090
fax: 781/828-6547 

Copyright ©2004 Medical Product Manufacturing News

Heat-Shrinkable Elastomer Tubing Introduced

Originally Published MPMN January 2004


Heat-Shrinkable Elastomer Tubing Introduced

Applications include catheter jackets

Norbert Sparrow
Palladium tubing from Cobalt Polymers uses Pebax resin in a 
heat-shrink formulation.

Nylon elastomer tubing that offers strength, flexibility, toughness, and a fine surface finish is now available in a heat-shrink formulation. Developed by Cobalt Polymers (Cloverdale, CA), the line of Palladium products reportedly is the first heat-shrink tubing to be made from Pebax resin.

"There are many possible applications," says company president Robert Foley. Especially promising, he notes, is the use of "long lengths of the material to jacket catheter shafts and cover braids or coils." This can save designers weeks of waiting for the right extrusion to come in, adds Foley.

Initially, eight different sizes will be maintained in stock. Off-the-shelf tubing will be available with inner diameters from 0.020 to 0.300 in. and in wall thicknesses from 0.0005 to 0.010 in. Requests for special sizes, hardnesses, and colors can be readily accommodated.

One of the material's properties that may surprise some users, according to Foley, is its expansion rate. "Even with ratios well above 4:1, the tubing maintains its form and ease of use as well as its flexibility."

Cobalt Polymers will introduce Palladium tubing at MD&M West in Anaheim, CA, in January 2004. The company has also announced that it is making free evaluation samples available.

Cobalt Polymers 
138 S. Cloverdale Blvd.
Cloverdale, CA 95425
tel: 800/337-0901
fax: 707/894-9083

Copyright ©2004 Medical Product Manufacturing News

Inductive Proximity Sensors Enable Reliable Process Monitoring

Originally Published MPMN January 2004


Inductive Proximity Sensors Enable Reliable Process Monitoring

The feedback signals achieve a 1.5-µm resolution

Rita Emmanouilidou
Based on ultralinear technology, a line of inductive proximity sensors is suited for use in automated manufacturing.

New sensor technology enhances the capabilities of inductive proximity sensors, making them suitable for use in automated manufacturing. Developed by Balluff (Florence, KY;, Ultralinear technology pairs traditional proximity sensor ruggedness with linear analog feedback signals for reliable process monitoring.

Conventional switching sensors use an oscillator coil assembly to generate an inductive eddy-current field that extends in front of the sensing surface. When a conducting metal is introduced into this field, an eddy current is induced in the metal. The change in current is detected and the sensor's output is energized.

Ultralinear sensors are based on this standard design. However, they generate a linear analog voltage or current proportional to the distance between the sensor's active surface and the metal target. The feedback signals have a resolution down to 1.5 µm. Applications that could benefit from this technology include parts sorting by size, shape, or material; detection of object orientation; and monitoring of the thermal expansion of ball screws and shaft imbalances on rotating machinery.

8125 Holton Dr.
Florence, KY 41042
tel: 800/543-8390
fax: 859/727-4826

Copyright ©2004 Medical Product Manufacturing News

On-Line Tool Simplifies Cold-Plate Selection

Originally Published MPMN January 2004


On-Line Tool Simplifies Cold-Plate Selection

Melody Lee (Click to go to site).

An on-line selector tool chooses up to three cold plates to fit a customer's need. The liquid-cooled plates are suitable for cooling power supplies in MRI systems, detectors in digital x-ray equipment, and medical lasers. Lytron Inc. (Woburn, MA) recently introduced this function, which selects from the company's 25 standard products, on its Web site, The results are based on user inputs of heat load, desired surface temperature, incoming- liquid temperature, surface area, and flow rate. If one of the standard products does not work for the customer's application, an on-line form directs inquiries to an engineer. The company's engineers will review the data to determine if a custom item is feasible. 

After selecting a cold plate, the tool plots the product's performance versus the required performance, as well as the liquid pressure drop. It also provides a printable quote with single-piece pricing. The form can be faxed back to Lytron Inc. to place an order. Orders received using this form receive a 10% discount. 

"Our Web site is designed to be the engineer's definitive source of thermal-management information," says president Charlie Carswell. "We realize that design engineers may prefer to size their own cold plates, so this tool is now available for global use 24 hours a day, seven days a week." 

In addition to the selector, the site contains information about the company's products, custom capabilities, and technical support. Descriptions, pictures, performance details, ordering information, and prices are given for each product. The technical-support section features application notes, product selection information, and reference data. 

Lytron's products range from cold plates to recirculating chillers. Its cooling products include compact and portable nonrefrigerated cooling systems, aluminum-oil coolers, copper or stainless-steel tube-tin heat exchangers, compact cold plates, and OEM coils.  

Copyright ©2004 Medical Product Manufacturing News

My Favorite Bookmarks

Originally Published MPMN January 2004


My Favorite Bookmarks

Mike Thomas,
Product Manager
LW Scientific Inc.

Mike Thomas

CLIA ( is the Clinical Laboratory Improvement Amendment program. It sets 
quality, accuracy, and reliability standards for laboratory tests, including waived tests, in vitro tests, and moderately to highly complex lab tests.

FDA ( has databases of medical devices, drugs, and 510(k) clearances. On this site you can search by keywords to find product codes, device classes, and 510(k) exemption status. You can see if your equipment has been registered, or search the Warning Letters database to learn from the mistakes of others. You don't want to be out of compliance!

Since manufacturing microscopes is our business, the Microscopy Primer from Florida State University ( is my favorite Web site. After five years in the business, I still go there every few weeks to learn new microscopy techniques, or when someone stumps me with a tough question. You can work a virtual microscope on your computer screen with the hundreds of Java interactive links to polish your microscopy techniques on-line. It's fun!

Another site I would recommend is the North American Industry Classification System (NAICS)/ U.S. Standard Industrial Classification (SIC) codes ( Every manufacturer should be familiar with its own product codes, especially if it does business internationally. Go to the Ask Dr. NAICS link for answers to many common questions about why the classification is important and how to use it for your advantage.

The federal Occupational Safety and Health Administration ( has important regulations regarding safety in the manufacturing and use of medical products. Find out if your equipment is compliant, or whether you need an exposure-control plan. There are also many helpful procedures listed to make sure you are safe. Here's a funny one: "1910.1030(d)(2)(xii) Mouth pipetting or suctioning of blood or other potentially infectious materials is prohibited." Don't get caught with a fine, or worse, death!

Many of you lead meetings...some long and boring. Why not energize your meetings with some fun games and stories from that will promote teamwork? Bring some Legos, spaghetti, Play-doh, marshmallows, and blindfolds to your next meeting. Play the "Hidden Agenda" game, or read a funny and relevant story like the "Beans up the Nose" story.

LW Scientific Inc. (Tucker, GA; is an American-owned, ISO 9001-certified manufacturer of laboratory microscopes, centrifuges, and other small lab equipment, selling through a worldwide network of distributors. 

Melody Lee

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