Multi-Position Airless Cylinders From Norgren

At TECO Pneumatic, virtually every application problem our customers present to us is solved with some sort of pneumatic hardware. One of the most interesting exceptions to this rule is provided by a remarkable new multi-position "airless cylinder" from Norgren.

Like a traditional air cylinder, this airless cylinder (a highly dynamic, electro-magnetic, direct drive linear motor,) consists of two working parts. A solid rod (or slider) functions like the rotor in a standard electric motor. It is mounted in a tube (which would be the stator in an electric motor). In this device advanced linear motor technology provides controlled motion rather than compressed air or hydraulic fluid. When properly guided, the slider operates without contacting the stator. This means that there are no wearing components and the device may be operated at speeds up to 4 inches per second in a class 1 clean room. Permanent neodymium magnets in the slider and windings in the stator create force. As an entirely electric device, with no gears, belts or ball screws, linear motors are ideal for applications that require high speed and the accurate positioning of multiple end stops.

The multi-position airless cylinder package consists of the linear motor actuator, an "H-block" guide assembly (if necessary,) a controller, a cable and a power supply. This complete hardware package can be ordered with a single part number. Programming is done on your laptop with a simple pull down menu. The required software is supplied with the controller. (Your PC can be disconnected once the command sequence is stored in the controller.) You can select either a guided or an unguided actuator based on the load you are controlling, between two load ranges and from a variety of stroke lengths.

Norgren linear motors will deliver up to 500 Newtons (112 pounds) peak force and have strokes up to 1460 mm (57 inches.) Positioning of this actuator is held to +/- 0.1 mm with zero backlash. The encapsulated motor windings, seals, microelectronics and an IP67 cable make the system fully submersible and immune to most wash down problems. The single cable used for both power control and feedback simplifies installation.

If you have a motion control application which calls for any of the following:

• Multiple programmable positions without mechanical switches

• Motion control without a fluid power utility

• Precise position control and repeatability

• High speeds and accelerations to 55 m/s2,

• Very short cycle times

• Programmable force limits

• Velocity profiling

Please contact TECO to see this remarkable new product.

Servo Valves From Parker Hannifin

Linear motors, such as those described on the previous page, are one approach to servo control. TECO Pneumatic also offers electro hydraulic and electro pneumatic servo control systems from Parker Hannifin Corporation. This hardware was first developed to manipulate the dynamic surfaces of missiles and aircraft. It is now widely used wherever a significant load must be positioned accurately along either a linear or rotary axis. Servo control valves will drive virtually any type of fluid power actuator. An electro pneumatic servo system will provide the same sort of "stiffness" that one expects to see in a hydraulic system. With this control technology it is possible to stop an air cylinder anywhere in its stroke with 0.001" repeatability or better.

A servo valve provides the link between the electronic and fluid power part of a control system. Control of position, velocity, acceleration, pressure, force, temperature, and even mass-flow, are possible with the appropriate system feedback . At the core of a Parker servo valve is a "torque motor", consisting of a pair of coils providing linear adjustment of pressure for precise positioning of a lapped spool. The spool section controls flow to each side of the piston in the actuator with zero dead-band. Repeatability and linearity are better than 1%. Valve response times can be as low as 3 – 5 ms.

Parker provides us with: Single stage pressure dividers that have 3-way or 4-way operation with flows up to 2.2 SCFM and operate at pressures up to 100 psi. Single stage 4-way flow control valves that flow up to 20 SCFM at 150 psi. Two stage 4-way flow control valves that flow up to 240 SCFM at 3000 psi. Their offering also includes power supplies and amplifiers, signal conditioners and pressure sensors.

Most servo control tasks are interesting and complex. A typical system will consist of a command signal source, dedicated electronics to process the feedback signal, the hydraulic or pneumatic servo valve, a fluid power actuator and a feedback device. Through Parker, TECO Pneumatic can specify and supply a complete control package tailored to your requirements.

At TECO Pneumatic we have been involved in servo applications that aim large airborne lasers, control tiny louvers in a high vacuum system, provide extraordinarily precise control of polishing pressures in semiconductor manufacturing applications and tilt the entire floor of a theater at an amusement park. If you have an application that calls for electro hydraulic or electro pneumatic servo control, please call TECO Pneumatic. We are fortunate that a Parker Hannifin servo engineer is resident in northern California and is available to work with us addressing your application.

High Density Valve Package From Humphrey Koganei

Many of the markets served by TECO Pneumatic demand increased valve function in ever more compact packages. Humphrey Products and their colleagues at Koganei continue to provide control solutions with improved valve density. An interesting example of this ability is the high density KJ solenoid valve manifold.

The KJ manifold provides either 8 or 16 solenoid valves in a very tight package. Humphrey/Koganei employ their tiny, 10mm wide, 010 series solenoid valves on the KJ manifold. This three-way, normally closed, direct acting valve is ideal for pilot operating other components. Both KJ manifolds are remarkably compact; the sixteen station version has a footprint of only 5.24" x 2.24". With common supply and exhaust connections, the KJ manifold is well suited for clean room applications. Each manifold incorporates integral push-in fittings in the output ports and may be DIN rail mounted. Red and green LED valve status indicators are standard. A manual override on each 010 valve makes it possible to test and trouble shoot any part of the pneumatic circuit controlled by this manifold without an electronic input.

At TECO Pneumatic we can tailor the basic KJ manifold to precisely suit your requirement for a high-density valve package. We have, for instance, modified the standard electric connector and deleted the standard LED’s to meet specific customer requirements. If your application calls for a lot of pneumatic control in a small package, please ask your TECO salesperson to see a sample of the KJ manifold from Humphrey Products.

Custom Gauge Isolator From TECO

In our past several Newsletters, we have focused on products designed and manufactured by TECO Pneumatic to satisfy a particular customer requirement. Illustrated here is another such product. This gauge isolator (or snubber) is intended to act as an interface between a process fluid and a pressure sensor.

All wetted parts of the gauge isolator are pure virgin Teflon, which makes it ideal for use with both aggressive and ultra pure fluids. The sensor port is separated from the process fluid by a Teflon‚ diaphragm. Isopropyl alcohol fills the space between the diaphragm and the gage. Currently, customers use our gauge isolators to monitor the pressure of hydrofluoric acid, hydrochloric acid and ammonia.

As shown, the device has a 1/4" NPT male pressure port and an 1/8" NPT female sensing port, but either connection can be modified as needed. We currently manufacture the isolator in four different configurations. In the illustration, a Parker/Convum MPS-3 pressure sensor (described in our Winter 2004 Newsletter) is threaded to the sensing port. Virtually any type of pressure sensor or mechanical gauge may be used.

If you need to monitor the pressure of an aggressive or ultra pure fluid, please contact your TECO Pneumatic salesperson. We will be happy to configure our gauge isolator to suit your requirement. In a more general sense, if you have looked at the range of standard products available to suit your application and come up short, consider TECO Pneumatic as a source for the unique product you need.

"These are my principles. If you don’t like them, I have others."
- Groucho Marx -

"The way to get things done is not to mind who gets the credit for doing them."
- Benjamin Jowitt -

"Nearly all men can stand adversity, but if you want to test a man’s character, give him power."
- Abraham Lincoln -

"Even if you are on the right track, you’ll get run over if you just sit there."
- Will Rogers -

"Silence is the unbearable repartee."
- Alexander Theroux -

"Every improvement in communication makes the bore more terrible."
- Frank Moore Colby -

"Age is a very high price to pay for maturity."
- Tom Stoppard -

Thanks to everyone who stopped by the TECO Pneumatic booth at the Semicon show in July. The event was the most upbeat in a number of years. It will be interesting to see how the show develops next year when the entire operation will be held at Moscone in San Francisco. TECO Pneumatic will be there!

Quarterly Thoughts have been a part of the TECO Pneumatic newsletter since its inception in 1990. A compilation of more than 400 of these items is now available to you at our website, www.tecopneumatic.com. Please visit our website, explore the wide range of information available there, and find a thought appropriate to your day.

TECO Pneumatic Inc., Box 1809, Pleasanton, CA 94566
(925) 426-8500. Fax (925) 426-9539