Enfield Technologies

Carbon Fork Fatigue Test With Closed Loop PID Control

frankgiuliano — Wed, 08 Feb 2012 19:39:26 +0000

Fatigue test on bike fork with a servo pneumatic actuator and closed loop PID.

S2 Servo Pneumatic Proportional Control System Featured in Design World

frankgiuliano — Wed, 25 Jan 2012 21:55:05 +0000

Enfield Technologies has introduced the S2 Servo Pneumatic Proportional Control System for variable positioning of air cylinders. The compelling aspect of the S2 is tight integration of control algorithms, electronics and mechanical components in one package. Focused on simplifying setup and attaining superior performance, Enfield designed the S2 as a directional control valve with an on-board closed-loop controller, high efficiency valve driver, and sensors to measure differential pressure in the cylinder. Inputs are simply power, cylinder position set-point signal, and cylinder position sensor feedback signal.

Enfield has provided the end user with ultimate flexibility in their design process. Instead of being locked into one brand, the S2 can be paired with any air cylinder brand and standard analog position sensors. This allows the customer to deploy best-of-breed components for their application. Designers can tackle high speed and high force applications with less cost and less space than electric drives for the same load capacity.

The innovative algorithm uses a cascaded control system with both position and pressure feedback. The result rivals electric drives while retaining the advantages of pneumatics for moving and holding high loads, space efficiency, and low cost. Their website shows a video of an application using 40 mm (1.5”) bore cylinder following a PLC command to move 25 kg (55 lb) to various positions at 1200 mm/s (50 in/s) with positional accuracy of 0.5%. Customers have also used the system for even more precise control. For example, a laboratory automation process was developed to provide 5 mm indexing with better than 0.25 mm accuracy for a tray of small samples moved by a 300 mm low friction guided cylinder with feedback. That’s better than 0.1% accuracy.

Enfield Technologies Reaches NFPA Foundation Legacy Builder Status

frankgiuliano — Sun, 21 Aug 2011 18:29:24 +0000

The NFPA Education and Technology Foundation congratulates Enfield Technologies for reaching its “Legacy Builder” giving level and demonstrating its commitment to the future development of the fluid power industry. A combination of their on-going, annual contribution and a special donation in the memory of their chief engineer emeritus, Vince McCarroll, raised Enfield Technologies to over $25,000 in cumulative donations and elevated their status to “Legacy Builder.” Enfield Technologies will be recognized in March at the 2012 Annual Conference with a special plaque commemorating the achievement.

Enfield Technologies president, R. Edwin Howe, said that “in seeking a way to honor Vince, we easily found that his character, interests, and ambitions were a good match with what the Foundation stands for. We had been working toward the Legacy Builder contribution level anyway; but this simply accelerated it.” According to Howe, “Vince loved technology, solving hard problems and inventing. He also felt very strongly about the work that NFPA was doing in research and education, and he was an active participant.”

NFPA encourages all of its members to reach Legacy Builder status in the Foundation. Such gifts help build a sustainable funding stream for critical fluid power research, education and recruitment programs. They also provide an ideal mechanism for honoring the contributions of industry innovators like Vince McCarroll.

To become a Legacy Builder donor, please go to Support the Foundation.

Link to original article: http://www.nfpa.com/misc/Reporter/ShowArticle.aspx?ID=269

Enfield Technologies Announces D1 PWM Valve Driver

frankgiuliano — Wed, 13 Apr 2011 19:49:34 +0000

The D1 PWM Valve Driver from Enfield Technologies is designed specifically to drive and manage proportional valves. Compact and easy to implement, the D1 converts proportional command voltage into a -1.1…1.1A current signal to drive the valve’s linear force motor. The low-cost D1 helps users avoid the effort and expense of characterizing valves and developing electronics for their application.

The D1 allows a 12 or 24 VDC power supply, to accommodate most applications. Its valve deadband, dither amplitude and maximum current are all adjustable. For applications using programmable logic controllers (PLCs) or computers, the D1 easily interfaces with the valve, eliminating the need to write valve management routines that consume valuable processing cycles needed for other machine functions.

Its digital closed loop current control implemented by software efficiently compensates for different types of perturbations such as change in the input voltage and change in the coil resistance due to temperature. Other features of the D1 Driver include short circuit protection, highly efficient design (no heat sink is required) and LED indicators for power and status/fault activity. With a temperature range of -40 degrees C. to 65 degrees C. (-40 degrees F to 150 degrees F), the versatile D1 is designed for use in a variety of environments.

The unit’s enclosed format is ideal for panel mount systems or applications where the electronics will be exposed to end-users. The D1 comes with a DIN clip for rail mounting, or the clip can be removed for flat surface mounting either from within the enclosure or from the bottom.

Original article can be found here: http://www.automation.com/content/enfield-valve-driver-efficiently-and-economically-manages-proportional-valves

Upfront CFD uncovers rare flow problem in medical respirator valve design

frankgiuliano — Tue, 01 Mar 2011 06:10:08 +0000

Sometimes an engineering problem can defy logic: My encounter with this phenomenon was a flow problem within the control valve of a medical respirator that showed characteristics similar to rare cases in nuclear reactor physics.

Fortunately our design team at Enfield Technologies had two things working in its favor: My nuclear reactor operator experience, and CFdesign, upfront computational fluid dynamics (CFD) software that gave us a good picture of flow characteristics within the control valve in the early design stages.

Defying Assumptions

Enfield Technologies specializes in designing proportional pneumatic controls for automation, medical equipment, animatronics, and specialty instrumentation. In this particular case, the valve that defied assumptions was the primary control element for inhaling and exhaling within a lightweight and portable (about the size of a toaster) respirator.

Valve designs at Enfield Technologies usually deal with choked-flow pneumatic applications, where the upstream pressure is typically much higher than the outlet pressure. It’s easier to design for choked-flow applications, since the flow profiles are simplified and the equations governing flow are well behaved.

The respirator valve, however, needed to operate with a non-linear flow profile in relation to the poppet position. A very shallow and well-behaved flow control was needed for the first 50 percent of the valve stroke, followed by a rather steep flow profile for the remaining 50 percent.

Many of the details regarding the entire system and how it would interact with the control valve were obtained by working closely with the client’s engineers. These discussions helped us understand all of the different modes of operation of the end product, whether lung dynamics would come into play, whether upstream conditions varied, and other features that dramatically affect system dynamics.

Medical Design – Proportional Control and Positioning of Pneumatic Cylinders Demonstration

frankgiuliano — Thu, 16 Dec 2010 13:14:56 +0000

Joel Gilmer from Enfield discusses proportional control and positioning of pneumatic cylinders.

The following link brings you to the video: http://machinedesign.com/video/servopneumatics-1215.

Medical Applications Tap Power of CFD

frankgiuliano — Sun, 01 Aug 2010 19:42:12 +0000

As natural as breathing. That phrase takes on new meaning when a medical condition makes ordinary breathing a moment-by-moment struggle. We generally don’t think about our blood

circulating until someone mentions heart attack or stroke. But in the medical field, these fundamentally human functions translate into daily design challenges as device manufacturers strive to understand and improve their life-critical products. DE looks at several design projects where computational fluid dynamics (CFD) software sheds light on complex fluid behaviors.

Enfield Technologies Makes Proportional Pneumatic Control More Affordable

frankgiuliano — Tue, 06 Apr 2010 18:13:59 +0000

Thanks to some innovative engineering, Enfield Technologies has reached an important goal – making a complete proportional pneumatic control system much more affordable.

A basic positioning system includes a proportional valve and control electronics manufactured by Enfield Technologies paired with a pneumatic actuator and a position sensor provided by a variety of highly regarded partner companies.

The same valves and control electronics used in motion control are also used for proportional pressure, flow, and force regulation applications.

During the last 18 months, Enfield Technologies has revised its sourcing and manufacturing processes. They have also reengineered several key products, adding new features, improving performance and reducing costs. This has allowed the company to offer price reductions averaging 42 percent on its primary components. For example, the LS-C10 controller dropped 70 percent, from $564 to $169.20, and the LS-V25s proportional valve dropped 45 percent, from $721 to $396.60. Enfield Technologies has also implemented volume discounts and an additional 5 percent bundle discount (bundle kits include a controller, valve and cable).

Enfield Technologies has added more than 35 technical resellers and integration partners over the last year. The company has also launched several new products, including the Enfinity System (C2 controller and M2 valves).

Original article can be found here: http://www.designnews.com/author.asp?section_id=1386&doc_id=211548

High-performance proportional valve and controller system

frankgiuliano — Tue, 29 Sep 2009 18:26:15 +0000

The Enfinity System combines an M2 pneumatic-control valve and a C2 controller, both available with an integrated driver.

The M2 instrument-grade, proportional, directional-control pneumatic valve uses a specialized linear-force motor instead of a proportional solenoid. Because the M2’s aperture is controlled at a very high speed, it responds quickly to set-point command changes.

The C2 is an enclosed high-speed, high-accuracy analog controller with multiple PID and feed-forward options. It features a user-friendly digital LCD/membrane keypad user interface and independent scaling of command and feedback signals.

Original article can be found here: http://machinedesign.com/article/high-performance-proportional-valve-and-controller-system-enfield-technologies-0929