|
At TECO Pneumatic, when we need the smoothest possible linear
motion or the most precise possible control of air pressure, we turn to our
friends at ControlAir. Most of their products are based on a thorough
understanding of rolling diaphragm technology. ControlAir cylinders use a
rolling diaphragm in place of the sliding dynamic seals found in most air
cylinders and provide virtually friction free conversion of fluid pressure
to linear force. (An interesting rolling diaphragm cylinder application is
described on page four of this newsletter.) ControlAir, an ISO 9001
registered company, also offers a wide range of precision air pressure
regulators capable of controlling output pressures to within 0.1% of full
range. In addition to pressure regulators, air cylinders, volume boosters and air relays, ControlAir makes a broad range of I/P and E/P transducers. These devices work like electronic air pressure regulators. They provide accurate conversion of a variable electronic input, either current or voltage, into a linearly proportional pneumatic output. There are a wide range of I/P devices available from ControlAir.
Utilizing internal solid-state pressure feedback circuitry, the ControlAir
Type 900 transducer provides precise, stable pressure outputs. The heart of
the Type 900 is a bimorph piezo actuator, which is encapsulated in a
protective skin. This skin protects the element from the humidity and
contaminants often found in industrial environments.
If you would like to explore precise control of motion and pressure, check out the ControlAir section of the TECO website, www.tecopneumatic.com, or ask your TECO salesperson about how the Type 900 and other ControlAir I/P devices might suit your requirements.
Versatile Pressure Sensors from Parker/Convum Parker/Convum covers the spectrum of industrial vacuum products. They offer an excellent assortment of vacuum cups for material handling, which range from 1mm to 200mm in diameter, are available in many shapes and in 9 standard materials. They also provide a number of filters specifically designed for use in vacuum systems and an excellent array of venturi vacuum generators. Venturi vacuum generators convert compressed air energy directly into vacuum with no moving parts. This part of the Parker/Convum line begins with simple devices for inline use and extends to complex units that incorporate in a single package one or more onboard solenoid valves, filters, mufflers, pressure switches, flow controls and timers. We will address these products in a future newsletter. Applications that call for ControlAir precision air pressure regulators (as discussed on the previous page) frequently demand a very accurate pressure sensor and output display. The Parker/Convum MPS series of pressure sensors will do this job and a lot more. The series includes a dozen different types of pressure sensors, which range from simple NPN/PNP or analog output devices to multiple channel units with LED display and sensors with all wetted parts 316L stainless steel. One Parker/Convum sensor even has a pressure range that extends to more than 8800 psi.
The pressure sensor we use most often at TECO Pneumatic is the versatile Parker/Convum MPS-3. It provides two independent NPN or PNP output signals. Operated as a pressure switch, it generates signal at a two adjustable pressure or vacuum points. Hysteresis may be field set by the operator. The unit can also operate as a window comparator, generating an output between settable "high" and "low" pressure points. The MPS-3 may also be specified with an analog output, producing a 1 to 5 VDC signal over its pressure range. This unit has an LED display, is panel mountable, and is just over an inch square. The MPS-3 may be specified with any of four pressure ranges; two vacuum ranges (0 to –30 inHg), a positive pressure range (to 145 psi) and a compound range spanning –14.7 to +72.5 psi. There are four field selectable units of measure. Pressure sensors similar in operation to the MPS-3 are available with 316L wetted parts, a red to green LED display (MPS-31,) and as a multiple channel LED display (MPS-7) for use with a remote pressure sensors.
Another very useful part of the MPS line is the MPS-8 mini transducer and sensor. These tiny sensors are only 10mm by 20mm by 16mm. They may be specified for either vacuum or compound sensing ranges and produce either an analog or NPN/PNP switched output. Connection is by M5 thru female thread (which allows the switch to be mounted directly in the pressure/vacuum line) or by an integral M5 male swivel fitting.
For the most environmentally demanding applications, Parker/Convum offers the MPS-5. This 1 to 5 VDC (+/- 0.04) analog output transducer has a 303 SUS housing and a 1/4" NPT male port. Linear accuracy is 0.5% of full scale. The wetted diaphragm is 316L on the pressure version and 630 SUS on the vacuum version. The MPS-5 is IP65 rated and CE marked. Setting the output and display parameters on Parker/Convum sensors is simple, but TECO will provide MPS units preset for your application if you wish. Many of these sensors are in stock at TECO. Please ask your TECO salesperson for more information on this broad line of pressure sensors, or visit the Parker/Convum section of the TECO Pneumatic website; www.tecopneumatic.com.
Miniature Pick & Place Units from Rotomation Rotomation specializes in devices that generate rotary motion. A wide range of torque and arcs of motion are available across this very broad product range. Rotomation makes four types of standard products:
Fairly new to the Rotomation series of pick and place actuators are the ultra miniature models PBL3 and PBM3. These tiny devices squeeze into an envelope of about 1.8" x 1.7" x 0.5". Each actuator is available with either a solid rod or a hollow rod which has a built in vacuum supply port. This vacuum capacity enables the actuator to hold, lift and rotate a small part. The PBM3 incorporates Hall effect switches to verify both linear and rotary position, the PBL3 does not.
These actuators are available with strokes up to 0.30" and will provide up to 190° of rod rotation. Given a 100-psi supply pressure, they will provide 0.45 inch pounds of torque, a push force of 4.9 pounds and a pull force of 3.6 pounds. The complete unit weighs just 1.6 oz without position sensors and 2.0 oz with the sensors on board. If you have a requirement to lift and rotate really tiny parts and can’t find a tool to do the job, please consider the PBL3 and PBM3 pick and place actuators from Rotomation.
Rotomation provides us with an excellent 47 page technical catalog. It is possible to specify 150 billion actuators with their standard part numbers. (If you are really demanding, they also are happy to build specials, including specials based on the PBL3/PBM3.) Their catalog data is available on paper, on line and on CD. Their drawings are downloadable on DWG/DXF format. If you would like a copy of the recently updated Rotomation catalog, please contact your TECO salesperson or visit the TECO website, www.tecopneumatic.com.
Custom Actuator Package from TECO As a fluid power distributor, TECO Pneumatic delivers hardware solutions for our customers’ motion control problems. Often the solution is a standard item cataloged by one of our suppliers, but sometimes the problem is more interesting than that. Recently a customer asked TECO for a clamp cylinder; simple enough. But this cylinder had to apply force very gently and smoothly against an exceptionally fragile product. It then had to disengage from the product an exactly determined distance, only a fraction of the clamping stroke. Both the clamp stroke and the retract stroke had to be precisely verified with position sensors. To complicate matters, the complete package had to fit into a defined and very tight envelope.
The illustration shows a proprietary product designed and manufactured by TECO that solves this problem. Our multi-actuator and sensor package is built around a small ControlAir rolling diaphragm air cylinder. This 0.70" bore, 0.70" stroke cylinder, along with a pair of Rulon bearings, provides exceptionally smooth clamping force against our customers’ delicate product. To precisely relieve the force on the product, a 1/2" bore Watson Pneumatics air cylinder is buried within the actuator package and acts in opposition to the ControlAir cylinder. The threaded OD on the Watson cylinder makes this mounting possible and allows for adjustment of the position of the cylinder. A pair of Baumer Electric inductive position sensors provides proof that the unit is either extended or retracted. With an OD of only 8mm, they fit right into our limited space. It is unlikely that you will ever need a cylinder control package exactly like this one, but when you do need an actuator or assembly of actuators that is truly out of the ordinary, please think of TECO Pneumatic. Your TECO representative will be happy to discuss your "interesting" motion control application.
- Anatole France - - Mignon Mclaughlin - - Henry David Thoreau - - Barry LePatner - - H. L. Mencken -
TECO Pneumatic will be participating in two trade shows in March. We’ll have new precision cylinder positioning hardware on display at each location. The American Vacuum Society’s Vacuum Show will be held at the Santa Clara Convention center on March 2nd & 3rd. Then on March 17th & 18th, we’ll be in the Central Valley Plant Engineering Show at the Modesto Center Plaza in downtown Modesto. At 2 p.m. on the 18th we’ll present a talk on air preparation at one of the technical sessions during the conference. If you need a ticket, please contact your TECO sales person or call our office.
|
||||||||||||||||||||||||||
TECO
Pneumatic Inc., Box 1809, Pleasanton, CA 94566 |
||||||||||||||||||||||||||
