Suppliers for original equipment manufacturers rely on a variety of innovative strategies to keep pace with a demanding, shifting marketplace.

A technician at Accudynamics conducts a coordinate-measuring machine inspection on a component destined for use in OEM equipment. Suppliers for makers of sensitive analytical instrumentation are increasingly adopting highly accurate measurement tools to keep quality high. Image: Accudynamics Inc.

As component supply chains go, the Large Hadron Collider (LHC) was perhaps the most complex in history. At the height of the building process, CERN, the Swiss research institution that managed the construction of the supercollider project, moved more than 120,000 tons of material around Europe and operated at least five international transport operations per day for more than five years.

The project created a significant opportunity for suppliers of many types and almost everything was custom-made.

Logistically the LHC project tested the limits of organizational capability. But, part by part, the process by which CERN acquired well-designed, quality components doesn't differ too much from the type of design, development, and logistics that takes place when a manufacturer of original equipment (an OEM) enters into an agreement with a supplier. This is especially true in the case of scientific instruments, where new development is a give-and-take between the supplier and the OEM to achieve optimal results for the performance of the final product. As is apparent throughout the scientific OEM supply chain, this interaction is the norm, even for mature commodity components such as fittings, screws, flanges, and mountings.

The responsibility of the OEM is to clearly provide the performance metrics, while the supplier must embark on a design program to use existing—or new—technology to meet the guidelines. Sometimes, the results are achieved through conventional solutions. Other times, remarkable innovations are required.

High power, with reliability
Though often seen merely as a support technology, power control is a crucial element of product design in the scientific instrument marketplace. Low-voltage sources adapted to miniaturized or mobile assemblies relatively quickly (think laptop computers, or cell phones); users of high-voltage sources faced the additional constraints of physics and topology when moving to modular, localized solutions.

Development work at EMCO High Voltage Corp., Sutter Creek, Calif., initially was confined to specialists who created a new design for each application. Thus, power supplies tended to be oversized to allow for safe routing of power. All high-voltage sources require a transformer plus rectifiers and capacitors. At 60 Hz, these components are large.

At EMCO, engineers started by using a low-voltage direct current (DC), typically in the range of 12 to 28 VDC, and then an oscillator-based inverter circuit to produce a low-voltage, high-frequency input for the transformer. This enabled high voltage in a small package, but also introduced the potential for arcing between high voltage points and between high voltage and ground. This meant that there were limits to how small these supplies could be while ensuring reliable operation.

The additional development of encapsulation techniques has contributed to safety, reliability, and standardization, especially in the last 10 years. A typical high-voltage component, like EMCO's A Series, can offer a mean-time-between-failure (MTBF) of millions of hours. Its use to product designers, however, may rely as much on the encapsulation technology that allows its Z height, or profile, to rise just 6.35 mm, far less than a typically high-voltage direct current (DC) power supply. This packaging allows the supply to be mounted in unit with the electronics module, eliminating extra high-voltage connectors and contributing greatly to module miniaturization.

Packaging requirements have also affected manufacturers of electric motors. Dave Beckstoffer, product manager at Portescap, West Chester, Pa., reports that its latest product line, the Athlonix DC coreless motors, reflects the push for increased power density and motor efficiency. Coreless DC motors are already efficient, with a self-supporting coil that is lightweight and offers a low inertia moment. However, repeatability and accuracy requirements have pushed a further motor development to the forefront.

Falling in between their micropump and high-capacity line, KNF Neuberger’s Mini Pump Series is designed to be highly configurable for use in scientific instrumentation. A structured elastic diaphragm design allows compact packaging for pumping gases.

"Scientific instruments, due to the precise nature of their operation, are driving more closed-loop solutions," says Beckstoffer, whose company specializes in DC, brushless DC, and step motors. Closed-loop motor assemblies package the encoder, or motor controller, with the motor. "The encoder feedback enables the machine to ensure the motion was completed correctly, ensuring the operation of the analyzer is correct," he says.

Tight packaging keeps current consumption of the encoder to a minimum, and typically includes a gearbox to increase torque output. For portable applications, the brushless slotted motors are autoclavable, enabling the OEMs to build them directly into the device without additional sealing. Stepper linear motors provide direct linear movement of the load, reducing the number of mechanical components in the OEM machine.

Design work at Portescap is intensive. The design teams review materials and create multiple designs, says Beckstoffer, settling on the most ideal for the application base design. Design specifications are created in detail at the beginning of the process and performance is measured against those specifications throughout the process. OEMs are involved at the initial stage of product development to understand both application requirements and end-product features.

As power demands grow across the analytical instrumentation marketplace, opportunities for innovation in power storage solutions abound. Capacitors have long been looked to as a potential way to enhance the performance of conventional batteries, which often fall short when called upon by high-powered portable scientific instruments to provide high-voltage power.

Cellergy, Bend, Ore., manufactures supercapacitors that can be connected in parallel to a battery, leveling load by reducing voltage drop. The net effect increases battery efficiency and operating time while keeping packaging volume to a minimum. Supercapacitors, or electrochemical double layer capacitors, offer unusually high energy density when compared with common capacitors. This is typically thousands of times greater than a high-capacity electrolytic capacitor, and when coupled to conventional batteries can enhance energy performance by delivering high-current pulses and limitless charge and discharge cycles.

Electrolytes used for these devices are typically aqueous (sulfuric acid, for example) or organic. Cellergy chose aqueous electrolytes, which allow the supercapacitor to be constructed far more cheaply, and still meet Restrictions on Hazardous Substances (RoHS) and Registration, Evaluation, Authorisation and Restriction of Chemical (REACH) regulations in Europe. Organic electrolytes for supercapacitors, on the other hand, typically contain toxic acetonitrile.

Supercapacitors can also help reduce size. Cellergy's prismatic supercapacitors can be as small as 12 mm by 12.5 mm yet offer output ranging from 1.4 to 18 V with a capacitance of 7 to 700 mF, depending on voltage and dimension.

"The patented printing technology used in manufacturing these supercapacitors enables the size and price reductions that make them viable choices in price-sensitive applications," says Cellergy's Gregg Smith, who facilitates U.S. distribution for several international OEM suppliers.

Optics suppliers adapt to miniaturization
Standardization and reliable performance doesn't lose importance for more complex components for OEMs. Spectrometers and laser modules, for example, are highly sensitive but nevertheless must conform to a variety of standard requirements from instrument makers.

To guarantee performance, tec5USA Inc., Plainview, N.Y., focuses on reproducibility, speed, installation flexibility, and timing accuracy as primary metrics to help keep its product line competitive. The company's spectrometer modules, detector array operating electronics, fiber optics components, probes, and data acquisition software all reflect an increased demand for tight specifications on sensitivity, says Gert Noll, CEO, tec5USA. "Also, quality is part of the design, such as materials selection," says Noll, referring to special aluminum alloys and ceramics used in the construction of the components.

Specializing in OEM-ready spectrometer modules, tec5USA pays close attention to how its installed products affect the performance of analytical instruments. Overall sensitivity has become a key demand of its customer base.

The company's latest product, the CGS USB Spectrometer Module, built specifically for OEM use, is the latest in a line of compact units for fast, wide-range ultraviolet near-infrared (UV-NIR) acquisition. Using the CGS optical engine from Carl Zeiss, a Hamamatsu S11156 detector chip, and tec5USA USB electronics, the CGS's entire configuration, including optics and electronics interfaces, can be changed according to customer specifications.

Packaging is also a high priority for Z-Laser Optoelektronik GmbH, Freiburg, Germany, which produces industrial laser modules, laser sources, and laser projectors used for positioning in processing industries and for machine vision in camera systems. Like other suppliers, the standard line of modules is customizable for output power, wavelength, housing, and optics. But standardized touches, like power supply voltages in the 5 to 30 VDC range for easy connection to machine supply voltage, help simplify new product design tasks for their customers, says Alexander Klein, marketing representative with Z-Laser.

The company's newest product line, the ZQ family of laser sources, responds to customer demands for higher power along with high beam quality and stability in a single package. The optical, thermal, and electronic components are in a single case, and the new ZQ2 laser, which has outputs up to 7,000 mW at 600 to 1100 nm, is equipped with a graphical user interface for setting power and monitoring parameters. As a result, the laser can be controlled remotely.

Pump makers respond to pressure
Often unseen and untouted when used in an OEM capacity, vacuum equipment is a crucial component in electron microscopy, chromatography, process engineering, environmental monitoring, medical equipment, and general laboratory research.

While many industrial operations and some types of laboratory research do not require efficient packaging, OEMs typically do. As a result, a vacuum pump manufacturer like KNF Neuberger, Hamilton, N.J., which makes diaphragm and piston pumps for gases, vacuum, and liquids, has adopted specialized measures to accommodate the requirements of OEMs. Called Project Pump, the effort capitalizes on KNF's modular systems design and has been in use for tens of thousands of pump design projects.

"This modularization of the pump design process enables reconfiguration and modification of the base pump to cost-effectively meet the OEM customer's requirements in as many dimensions as possible," says Richard Rauth, marketing communications manager at KNF Neuberger.

The KNF approach is also illustrative of the goal by large OEM suppliers to enhance their appeal to OEMs through innovative solutions. On the technical side, KNF has implemented compact brushless DC motors in serial production for reciprocating (diaphragm and piston) pumps; offered a wireless Bluetooth-enabled handheld controller for laboratory vacuum systems; and achieved 230 psig pressure levels in its small-format liquid pumps. Finally, it launched mid-range metering pumps, which combine durable diaphragm technology with stepper motors and solenoid drives to provide better accuracy. This represents a lower-cost alternative to typical metering and dosing technologies, says Rauth.

On the reliability side, KNF has adopted a "design life threshold" approach rather than the typical mean-time-between-failure (MTBF) for its component selection process. New designs are accompanied by a life test protocol, and the company frequently tests the designs at the customer's actual system operating points.

Finally, the manufacturing side has seen major changes in KNF's approach to continuous process improvement. A cellular "KanBan" manufacturing process, accompanied by a process optimization team, has been implemented at the company's five locations in Europe and the United States to rationalize process step functions and facility equipment selections.

These measures are meant to not just help their customers, but also to respond to a variety of trends in the vacuum markets. Foremost is the push to achieve better performance from smaller pump sizes. With the battery typically the dominant component contributing to size and weight, the power budget for the pump is continually shrinking.

A temperature-controlled laser source improves wavelength stability in Z-Laser Optoelektronik’s re-designed ZQ line of laser sources. To keep their products flexible enough for many projector applications, optics, electronics, and temperature control are integrated.

"There is also a growing trend to reduce, for a variety of reasons, the amount of sample and reagents consumed in analytical and diagnostic equipment. This means systems are using smaller diameter fluid paths, increasing the pressures required to move the fluids through the system. With the complementary trend to reduce the overall system size, this means there is an increased performance requirement from a smaller pump size," says Rauth.

Innovation, found in the most basic components
Innovation in OEM parts isn't limited to complex subsystems like ultracapacitors and vacuum pumps. According to Robert Lipsett, engineering manager for Thomson BSA, a division of Thomson Industries Inc. based in San Jose, Calif., the components that his company manufactures, including screws and nuts, can have a significant effect on the performance of an OEM instrument.

"Improper design of a lead screw can result in failure in literally a matter of minutes. I've seen screws fail in 10 to 15 minutes," says Lipsett. Certain types of friction, when coupled with poor materials choice and improper design can overheat lead screws."When using lead screws, you have to manage the amount of heat generation. Other factors such as pressure velocity can make a big difference, too."

A lead screw is designed to convert turning motion to linear motion, and is frequently used in OEM equipment for actuator assemblies. This type of screw, made from stainless steel and paired with a polymer nut, shines in scanning applications, providing maintenance-free accuracy. The anti-backlash style of the nut minimizes movement between the nut and the screw.

"Our manufacturing process stresses accuracy and repeatability, as well as clean construction materials. Our lead screws typically do not require lubrication because of the additives built into the polymers," says Lipsett.

Materials selection is important to Thomson BSA. Polymer-based lead nut technology has allowed the company to achieve greater package. When an OEM orders lead screw parts, it typically submits application data that may include load, speed, duty cycle, accuracy, and repeatability. Based on these metrics, Thomson works with the OEM to find the type, size, and correct style of nut. At that point, says Lipsett, the choice must be made whether a standard configuration is possible or a geometrically customized solution needs to be integrated.

"In that case, the nut becomes part of the next level of integration. We work together on a CAD [computer-aided design] platform and use collaborative tools to achieve the correct geometry that optimizes space and performance," says Lipsett.

Often, this process helps Thomson expands its services to the client. The discussion might include an adjacent frame component or other assembly that may require a linear bearing, a product that Thomson also sells. This type of interaction is common, Lipsett says. By sales dollars, about 60% of Thomson’s lead screw business is customized.

Thomson has proprietary equipment to chart the lead accuracy of the screws themselves, but in some respects it is a forensics task to determine how much a screw design affects overall performance. Product testing is important for guaranteeing repeatability of certain laboratory tasks, says Lipsett, such as dispensing fluid into a small vial, or a scanning an image on a microscopy stage without ripples or distortion. "The commonality of most of our applications is that some level of precision is required or critical to that application."

Metric lead screws, made by Thomson BSA for use in a variety of analytical instruments, convert motion from rotational to linear. OEMs require a high level of maintenance-free accuracy and repeatability from these components.

Cast and machined assemblies required
Cast and machined assemblies are also crucial to OEMs. Sensitive instrumentation often requires parts made from particular materials, or to highly exacting dimensions.

Insaco, Quakertown, Pa., for example, provides a wide variety of ceramic, crystal, and metallic components to industrial and scientific customers. Like many OEMs, the company occupies a middle position in the supply chain. As a machining company, it doesn't produce any materials, nor does it stock for resale. It does buy its own materials to fabricate parts, and one of its strengths is the ability to produce small lot or single-piece orders.

Accudynamics of Lakeville, Mass., builds precision cast and machined assemblies to customer specifications that require tight tolerances and high complexity. A typical example of the company's product line is a baseplate and housing for an optical assembly for use in a measuring instrument.

"We partner with our customers from prototype to production to ensure that reliable assemblies are cost-effectively produced," says Joe Guterl.

The design process has been highly streamlined. Accudynamics only requires a CAD solid model as the basis for all of the casting, machining, assembly, and inspection work. After working with the customer to select the appropriate casting process, Accudynamics takes care of the rest.

Guterl says system cost, improved reliability, and reduced complexity are the top demands from its medical and scientific OEM customers. These qualities are achieved by adhering to specifications. All critical features of a component or assembly supplied by the company are measured on coordinate measuring machines to ensure compliance to specification. Because many of Accudynamics’ customers subject assemblies to life testing after installation into their systems, this capability is of high importance. However, the increasing use of automation in both medical and scientific instruments requires more complex assemblies and systems and a greater variety of materials.

To accommodate this evolution, Accudynamics, has invested in CNC machining centers, lathes, wire electrical discharge machining systems, and 7-coordinate measuring machines. "Replacing machined assemblies that contain multiple parts with single-piece machined castings is a simple way to reduce cost and complexity while improving reliability. Many of our customers do not realize that the payback on this investment can be realized in a short time for low quantity instrument production. Assembly cost savings can approach 75% and piece count reductions of 90% are common," says Guterl.

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