Eddy current clutches the regutron 3 dcrs digital speed control is a costeffective way to upgrade existing analog eddy current clutch controllers. Us3488535a permanent magnet eddy current brake or clutch. The eddy current clutch prototype doesnt meet the torque requirement of 193 nm on the slip speed range see table 3, because of clutch geometric constraints imposed by the retro fit. The drive unit consists of a constant speed induction motor and an integral magnetic clutch, or eddy current coupling, assembled in a common housing. If playback doesnt begin shortly, try restarting your. While full braking torque is possible independent of slip speed, eddy current effects can increase the dynamic braking torque over a static calibrated value by as much as 7% to 8% per rpm increase in speed. In the basic form, the eddy current drive consists of an ac motor and an electrically controlled magnetic clutch. The clutch contains a fixed speed rotor and an adjustable speed rotor separated by a small air gap. Eddycurrent clutches and fluid couplings trade press. Esr 0557 overhaul of eddy current clutch and gear box. Us3601641a eddy current andor induction brake or clutch.
This easytooperate controller provides standalone control of a single magnetic drive or accurate coordination of more complex multidrive systems such as series pump applications. If the stator of an induction motor or a synchronous motor is mounted to rotate independently of the rotor, an eddy current clutch results. Medical imaging equipment, water handling systems, conveyors, robotic systems and rotary and linear actuators are among the many devices that may be fitted with electric friction brakes to hold their loads in place when the power is off. Weve created a new line of clutches for some of the most popular tractor models in the industry.
Design and experimental demonstration of a seamless automated. The specific loss factor pwb for eddy current losses is. Eddy current drive is a combination of a constant speed ac induction motor, coupled to an eddy current clutch. Eddy current dynamometers dynos providing precise control and low maintenance. The input shaft directly coupled to the motor and variable speed output shaft is connected to load. The thermal load on the power distribution system theref ore needed to be reduced to prevent the frequent overload trips. Variable frequency drives and dc drives operate by electronically altering the input power to control the speed of the motor. Step 2 print the rma form and put it in a box with the parts for repair.
Design optimization of an axialfield eddycurrent magnetic coupling. Eddycurrent drives can produce more torque at low speed than an induction motor and vfd. The drive motor, with a full load amp r ating of 250 amps, was at times drawing over 900 amps. The armature or rotor is constructed so that when the winding is excited with direct current, magnetic pole pieces are formed. Eddy current clutches eddy current clutches are so named because they in duce eddy currents into a metal cylinder or drum. Engineered for the demands of heavy industry, companies in sectors from transportation, energy, oil drilling, steel, shipping and more depend on stromag equipment and replacement parts to keep operations running and safe. The inductor includes a plurality of pole shoes of alternating magnetic polarity arranged in an annular ring and a plurality of permanent magnets disposed intermediate the pole shoes. One part of the clutch contains slip rings and a winding figure 428a. Eddy current drive consists of a totally enclosed, fan cooled tefc. Request pdf design of an eddy current torque bypass clutch for seamless automated manual transmissions of electric and hybrid vehicles this paper.
The principle of eddy current coupling makes it possi ble to obtain a wide range of stepless, adjustable speeds directly from industrial a. The design procedure is based on a torque formula derived from a 3d analytical model and a. The eddy current coupling or clutch is oldschool technology, but their robust design is appreciated by many. At that time, the municipality replaced their outdated analog controlling system for the eddy current clutch to a new digital dynamatic ec2000 high power clutch controller. The setup operates like an eddy current brake, a device commonly used in heavy vehicles to dissipate kinetic energy by generating eddy currents. The eddycurrent drive or clutch is a slip device consisting of two rotating elements that are coupled by a magnetic field. The eddy current clutch acts as a rotating transformer similar to a motor. Calculation methods for eddy current losses at the example of a permanent excited synchronous machine inside the threshing cylinder of a combine harvester abstract. Eddy current drives, also known generically as magnetic drives, eddy current clutches or magnetic clutches are driven at constant speed by an ac motor and utilize a simple electromagnetic device to control torque and speed to the driven load. Thus the transferable moment increases with the relative rpm. The subsequent analysis is based on this simple model. Eddy current brake design for operation with extreme back.
Eddy current transmission drive kingstone model works. The prototype performed a seamless shift on a test bench demonstrating the viability of using an eddy current clutch for torque bypass clutches in amts. Eddy current clutches or eddy current slip coupling are available in a broad range of sizes and speed up to thousands of kilowatts in both vertical and horizontal configurations. Eddy current clutches articles, news and companies. Eddycurrent clutches and fluid couplings upcoming seminars. Tech talk february 2011 eddy current drives holland industrial. A slight eddy current effect is present in a hysteresis brake or clutch.
Eddy current clutches the regutron 3 dcrs digital speed control is a costeffective way to upgrade existing analog eddycurrent clutch controllers. Design and experimental demonstration of a seamless. May 01, 2016 possible improvements of the eddy current clutch include the use of steel with a higher saturation level for the stator and the doubly toothed rotor. They are available in standard and high speed models with many speed and torque versions. Figure 2 shows the schematic diagram of a simple eddy current brake with only one magnet around it. Eddy current brakes are best substitutes for ordinary brakes, which are being used nowadays in road vehicles even in trains, because of their jerkfree operation. An eddy current brake, also known as an induction brake, electric brake or electric retarder, is a device used to slow or stop a moving object by dissipating its kinetic energy as heat. Eddycurrent clutch article about eddycurrent clutch by. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed. Couplings couplings for metalrolling mills b21b 3514. The eddy current drive or clutch is a slip device consisting of two rotating elements that.
When switching to a vfd for a constant torque load, the motor and the drive may require being oversized by a factor of 150% to 200%. Long stator end effects could be modeled by simply modeling the entire length of the plate in the present style of analysis, adding a few extra wavelengths of stator on either side of. We have the most extensive experience, and we develop the highest quality ect inspection products. Step 1 click the green button above to add the part and complete the rma form. In mountain areas where continuous braking force is needed, for a long time, the eddy current braking. Eddy current clutch working, application, advantages and.
While full braking torque is possible independent of slip speed, eddycurrent effects can increase the dynamic braking torque over a static calibrated value by as much as 7% to 8% per rpm increase in speed. The coils are excited with dc and attached to the mechanical load. An eddy current andor induction brake or clutch comprised of, a braking inductor and a ferromagnetic eddy current conductor arranged for relative rotation with respect to one another. The eddycurrent coupling or clutch is oldschool technology, but their robust design is appreciated by many. An eddy current coupling 4 is proposed, with a first movable coupling element. Huge energy savings potential operating centrifugal fans, pumps and compressors vary frequency of electrical supply to an induction motor to vary the motor speed. This webinar is intended to preserve the knowledge of how they work as well as their unique repair requirements. Other specialized motors ac motors electronics textbook. Eddycurrent systems, control drives stromag pdf catalogs. As an application engineering manufacturer, dynamatic offers the most complete line of electromagnetic drives, brakes, and digital controls, centered on the worldrenowned dynamatic brand. Head rush is the only company to use magnetic eddy current braking technology in climbing, free fall, and zip line devices, and the difference shows.
Design of an eddy current torque bypass clutch for. Design of an eddy current torque bypass clutch for seamless. Drive source international dsi is the worlds leading manufacturer of eddy current adjustable speed drives, brakes and controls. After the motor has reached its target speed, its controller engages the eddy clutch. The medium of torque transmission is a controlled magnetic field, generated by a stationary. We provide repair services from 56 frame through 49 to 63.
Variable frequency drives vfds popular speed control devices used in industrial, commercial. Eddy current drives for industrial automation dynaspede. The companies featured in the following listing offer a comprehensive range of clutches. The potential of eddy current clutches is assessed from a representative case study consisting of a. York specializes in services such as eddy current clutch repair. A slight eddycurrent effect is present in a hysteresis brake or clutch. However, unlike friction brakes, in which the drag force that stops the moving object is provided by friction between two surfaces pressed together, the drag. Us3488535a us3488535da us3488535a us 3488535 a us3488535 a us 3488535a us 3488535d a us3488535d a us 3488535da us 3488535 a us3488535 a us 3488535a authority us united states prior art keywords eddy current pole magnets permanent magnet flux prior art date 19670922 legal status the legal status is an assumption and is not a legal conclusion. Zetec is the industry leader for costeffective eddy current testing ect in complex applications. Seamless gearshift measurement figure 16 shows a complete upshift sequence using the eddy current clutch with a constant 16adc excitation current in the clutch electromagnet. Also a time dependent study was done to show the development of the same eddy currents in the disc with deceleration.
The primary elements of eddy current variable speed drive are an ac motor, an eddy current clutch, a tacho generator and a seperate small solidstate electronic. We can repair your minster machine co scrb52 in our facility. Possible improvements of the eddy current clutch include the use of steel with a higher saturation level for the stator and the doubly toothed rotor. The squirrel cage rotor is attached to the driving motor. Expired lifetime application number inventor max baermann original assignee max. Our commitment to innovation and quality doesnt end at engine parts. The plant engineer also wanted to increase the torque output to the drawbench, improve overall drive.
Dynamatic eddy current drivesbrakes heco all systems go. Our eddy current dynos are simple, cost effective, torque measuring devices for a large range of test purposes. Minster machine co scrb52 cyclemite eddy current clutch control. Reliance brand clutch discs are made from the strongest materials for your tractor application. The function of an eddy current clutch is to transmit a controlled torque from the induction motor,prime mover to the load. A threestory high 1,650 horsepower pump, 4,160 volt synchronous motor, and eddy current drive clutch at a wastewater treatment plant went in for its routine maintenance. A basic analysis of a long stator eddy current brake has been presented in this notebook. New electrical drive concepts make it possible to put a high functionality into a restricted structural form. Eddy current clutch hydrostatic drives wound rotor motor dc drives.
Dynamatic adjustable speed drives, brakes and controls oem. The inductor includes a plurality of pole shoes of alternating magnetic polarity arranged in an annular ring and a plurality of permanent magnets disposed. In contrast to the drive and brake elements described previously, the torque in eddy current clutches and brakes fig. The drive motor is started with no dc excitation to the clutch. A stationary study was done to evaluate the eddy current generated in the disc.
Minster machine co scrb52 cyclemite eddy current clutch. Diagram 1 eddy current clutch and gearbox assembly 2 general. Our eddy current brake technology is extremely reliable, smooth, and low maintenance. Variable frequency drives vfds popular speed control devices used in industrial, commercial and residential applications. Eddy current clutches articles about eddy current clutches. Eddycurrent clutches consist of a field, ta chometer, and eddycurrent control.
The function of an eddy current clutch is to transmit a controlled torque from the induction motor,prime mover to the load driven machine. A set of simple experiments is proposed to measure eddy current losses and to relate them to various relevant parameters. Kinetics eddy current clutch field exciter is a scr regulated rectifier system designed for the application of supplying regulated variable dc power. Because eddy current couplings and fluid couplings are uncommon, the institutional knowledge about them is being lost. Pdf design and experimental demonstration of a seamless. Dynaspede offers a comprehensive range of eddy current clutches, brakes or clutch brake combinations from fractional through integral horsepower range for applications demanding close unidirectional or bidirectional control of torque at relatively highspeed levels. However, unlike friction brakes, in which the drag force that stops the moving object is provided by friction between two surfaces pressed together, the drag force in an eddy current brake is an electromagnetic.
After that the reaction by eddy currents doesnt play a role in the iron because of the use of thin laminated sheet steel and in the magnets because of the little conductance, but it has to be taken into account in construction elements. An eddy current drive sometimes called a dynamatic drive, after one of the most common brand names consists of a fixed speed motor generally an induction motor and an eddy current clutch. Our technology the science of eddy current magnetic braking. The two major parts of the eddycurrent clutch are the drum assembly and the output rotor and shaft assembly. An eddy current clutch would be highly controllable, simple to manufacture, lowcost, robust, and do not wear compared to friction clutches.
Eddy current clutches or eddy current slip coupling are available in a broad range of sizes and speed up to thousands of kilowatts in both vertical and. Stromag sas unit 87 rocco drive victoria 3179telfax. Isc companies magnetic technologies ltd mayr corporation motion industries. High quality eddy current testing solutions for complete inspections. Eddy current drives can produce more torque at low speed than an induction motor and vfd. An eddy current clutch ecc drive is a device used to convert constant speed rotation input into adjustable speed output. The eddycurrent drive also called a magneticallycoupled adjustable speed drive, which consists of an eddycurrent clutch and associated controls, is favored for heavyduty applications with high starting torque and severe shock loads.
Eddy current, as well as a variety of related products and services. Is it costeffective to replace old eddycurrent drives. Eddy current clutches articles, news and companies related. They are an adjustable speed drive and provide soft starting capability. Dynaspede offers a comprehensive range of eddy current clutches, brakes or clutchbrake combinations from fractional through integral horsepower range for applications demanding close unidirectional or bidirectional control of torque at relatively highspeed levels. The braking is frictionfree with no contacting parts. An eddy current drive, also known generically as a magnetic drive, eddy current clutch or magnetic clutch, is an electromechanical variable speed drive that. Welcome to the premier industrial source for clutches. Affiliated distributors applied power solutions bearing headquarters dalton bearing service, inc. Eddy current variable speed drive systems modern pumping today.
844 1527 570 30 985 356 1282 1314 36 965 517 645 370 309 193 856 1355 304 509 819 1270 805 446 33 486 337 1453 431 1345 1433 1199 412