Sunon’s MagLev® Technology
provides a fan design created to provide superior performance, low noise
and long life. By using magnetic levitation force (MagLev), these fans
feature zero friction with no contact between shaft and bearing. With
excellent rotational stability, the MagLev fan eliminates vibration and
typical wobble and shaking typically experienced in fan motors. MagLev
also provides excellent high temperature endurance that results in long
life. And, MagLev models also feature all-plastic manufacture of major
items for optimal insulation resistance and electrostatic discharge (ESD)
The results are clear; Sunon’s MagLev technology and application
to the manufacturing process assures you of quality fan products that
offer a true solution to equipment and systems cooling, with the promise
of lower cost of ownership and long service life.
Background on MagLev Motor Fan Development
As the global leader in heat dissipation solutions, Sunonwealth Electric
Machine Industry Co. has devoted itself to research in the field of fan
motors. The firm has produced many innovative designs and technologies
over the years. SUNON realizes the importance of breaking through the
architectural bottleneck of traditional motors in order to sustain its
competitive advantage in the realm of fan motors. Sunon's long term mission
therefore has been to develop products capable of overcoming the problems
of noise, abrasion, and short service life that beset traditional fan
To achieve this goal and fulfill the commitment of providing the best
heat dissipation solutions in the field, SUNON has invested huge amounts
of capital and manpower in research and development work. The company was
proud to launch in the fourth quarter of 1999 the world's first MagLev
motor fan featuring zero friction and no contact between the shaft and
bearing during operation. On hitting the market, the new low-noise, long-life,
and high temperature endurance fan quickly won plaudits from international
leading manufacturers and became the world's most noticed high performance
The name MagLev is derived from Magnetic Levitation System, the industry-leading
fan that was first introduced by Sunon in 1999. In 2003, Sunon unveiled
the newly renamed MagLev to more concisely convey the meaning of the product.
With MagLev, you enjoy the high level of precision that comes with this
technology, but with a new simplified name.
MagLev - The Quietest Advanced Technology
The patented MagLev design is based on magnetic principles and forces
that not only propel the fan but also ensure stable rotation over its
entire 360 degrees of movement. Utilizing the attraction of the magnetic
levitation force, MagLev eliminates the wobbling and shaking problems
of traditional motor fans. With this new technology, the MagLev fan propeller
is suspended in air during rotation so that the shaft and bearing do not
come into direct contact with each other to create friction.
The result is a new and improved fan with a low noise level, high temperature
endurance, and long life. These qualities combine to place the Sunon MagLev
Motor Fan into a world class category product. Since the fourth quarter
of 1999, when Sunon first introduced the MagLev motor fan, over fifty
million units have been shipped to renowned manufacturers all over the
world. Substantial contributions have been made by Sunon's Magnetic Levitation
motor fans to various industries and products that require high-level
heat transfer, such as notebook computers, servers, projectors, and stereo
About the SUNON MagLev Motor Fan
Traditional fans apply the principle of like-pole repulsion to rotate.
But with no control exerted over blade trajectory, the fan blades tend
to produce irregular shuddering and vibrations. After long-term use, the
shaft will cause severe abrasion on the bearings, distorting them into
a horn shape. The worn-out fan then starts to produce mechanical noises
and its life-time is shortened.
The unique feature of SUNON's MagLev motor fan is that the path of the
flan blades during operation is magnetically controlled by Sunon's patented
MagLev System. The result is that the shaft and bearing have no direct
contact during operation and so experience no friction no matter how the
fan is oriented. This means that the characteristic abrasion noises of
worn-out components are not produced and also allows a service life of
50,000 hours or even longer at room temperature. Considering the distinctive
internal structure of MagLev motor fans, SUNON has summarized the following
two major features to help consumers identify and select the product.
- The MagLev system creates 360° attraction on the rotor, which
results in stable rotation
- MagLev flux acts perpendicular to the standard magnetic flux
In a traditional fan, the embedded magnets of the rotor
and the stator exert repulsive forces, and it is this continuous force
of repulsion that makes the fan spin. This is the basic principle behind
all cooling fans. If we visualize the magnetic forces between the stator
and the rotor, we see only dense lines of standard magnetic flux running
without any control mechanism to stabilize vibration of the blade rotor
during the repulsion-driven operation. SUNON's MagLev motor fan includes
just such a control mechanism in its design. This requires that each fan,
in addition to standard magnetic flux, contains MagLev flux required to
sustain for the unique MagLev orbit in its design.
Where does MagLev flux come from? A MagLev cross-section view reveals
a uniquely designed set of conductive elements on the main board-the MagLev
plate. This MagLev plate and the embedded magnets in the fan blades together
generate comprehensive vertical magnetic forces, which is the MagLev flux,
the unique patented invention of MagLev motor fan. From the cross-section,
the standard magnetic flux and MagLev flux form a 90-degree vertical angle,
in others words, the MagLev flux acts perpendicular to the standard magnetic
flux. This is the first key trait to use to identify a MagLev motor fan.
The design of vertically intersected standard magnetic flux and MagLev
flux ensures that the rotator is affixed to the MagLev orbit. Therefore,
regardless of the mounting angle the fan, the shaft will always rotate
around a fixed point and at a constant distance from the bearing without
coming in contact with it to produce friction or mechanical noise. The
problem of bearings being worn down into an oval shape or horn aperture
after long use is effectively resolved.
The greatest benefit with MagLev flux is in fact the 360-degree complete
force of attraction between the conductive element (MagLev plate) and
the rotor above it. This ensures an evenly-distributed force of attraction
to help keep the optimal balance of the rotor during operation and to
avoid shuddering or instability. Fans with well-balanced blades not only
last longer but produce a steady air flow. In short, the second easy trait
for identification of the MagLev motor fan is that the Maglev system creates
360° attraction on the rotor, which results in stable rotation.
Comparison Between Sunon MagLev Fan and Traditional Fan
| (A) SUNON MagLev Fan
||(B) Traditional Fan
|Possesses 3 important factors: the magnet
plate, the magnet and the stator
The resulting interaction between the magnet plate and the magnet
pulls the rotor downward in a full 360-degrees. Through the lower
center of gravity, the rotor runs stably in a consistent orbit.
|2 factors: the magnet and the stator
The conventional fan utilizes a deviating magnetic center to attract
the rotor downwards. This kind of technology causes the rotor to vibrate
violently due to both the lack of a consistent orbit and a deviation
of the magnetic center.
In the traditional DC brush-less fan motor design, the impeller rotor
(simply called Rotor) by means of a shaft which extended through the bore
of oil-impregnanted bearing, or Sleeve bearing, pivotally held in the
center position of motor stator. A suitable air gap was maintained between
the rotor and the stator. Of course, there must be gap between shaft and
bearing bore, otherwise, the shaft would be tight-locked and unable to
rotate. The stator assembly (simply called stator) after connected to
power supply will generate induced magnet flux between rotor and stator.
With the control of driving circuitry the fan motor will start to rotate.
In a traditional fan motor structure, there is an impeller rotor, a motor
stator and a driving circuitry. The rotor is pivotally joined to the stator
by the rotor shaft and bearing system. The rotor is driven to rotate by
the induced magnetic field between stator and rotor as shown in Figure
Advantages of Sleeve Bearing
- More impact-resistant, less damage resulted during delivery.
- Sleeve bearings cost much lower in comparison with ball bearings.
Imperfections of Sleeve Bearing
- Dust from outside may penetrated into bearing and mix with nitride
particles to clog the motor, which may result in noise and much slower
operation of the motor.The inner surface of bearing bore easily gets
worn and influences the performance.The space between the shaft and
sleeve-bearing bore is small this results in rough uneven start-ups.
Ball bearing workings utilize small metal balls for rotation. Since they
have only point-contacts rotation can be started easily. With the use
of springs to hold the outer metal ring of the ball bearing above, the
weight of the entire rotor can sit on the ball bearing, indirectly supported
by the springs. Therefore, ball bearings are ideal for use in portable
devices with various mounting angles. However, caution should be used
to prevent the product from falling and impact damaging the ball bearing,
which could lead to noise and shortened product life-time.
Advantages of Ball Bearing
- Steel ball bearings have an operating life much longer than that
of sleeve bearings.
- However, the product must avoid rough handling or being dropped
on the ground.
Imperfections of Ball Bearing
- Ball bearings are quite weak. It cannot bear any external impact.
- When the fan motor is operating, the steel balls inside will generate
a higher rotational noise than that of a sleeve bearing.
- High price makes it uneasy to compete with sleeve bearings.
- Limitation on both supply sources and supply quantities make it
unacceptable for mass production needs.
- The use of tiny assemblies such as springs, result in inefficiencies
for mass production.
Sunon MagLev Motor Fan
Sunon is renowned for its revolutionary MagLev System. Here is a good
example to help in understanding the principle behind it. When a spinning
top (a kind of toy) is thrown, the top continues to accelerate even as
it hits the ground. During this acceleration the top tilts and sways until
a consistent speed is obtained. At this point, the top will balance itself
- e.g. the swaying and tilting have faded - and has become fixed
perpendicular to the ground. This is the simple concept that Sunon's MagLev
System roots from.
From the illustration above, we know that no matter how
the motor fan is mounted, the force induced by the existing magnet inside
the hub and the magnetic plate that is added to the PCB of the fan attracts
the rotor continually. This results in the rotor rotating perpendicular
to the ground with a constant distance between bearing and shaft without
any contact. Therefore, no rubs or noise can occur. The operating life
of the motor fan is extremely long. This is the spectacular contribution
provided by the MagLev design.
- MagLev system helps the impeller to rotate evenly in a fixed orbit
within the orbit center. Consequently, the shaft inside the Vapo bearing
bore turns without creating friction. The bearing bore is hardly ever
abraded into irregular or oval shapes such as seen in conventional
fans. Hence the operating life of the bearing becomes very long.
- The shaft inside the bearing bore is in friction with nothing except
air, the fan motor starts up easily.
- This new system removes the use of oil rings and washers, thus leaving
space for the release of gas occured during normal operation. No more
clogging problems. Hence, the fan motor may operates smoothly for
quite a long time.
- The use of magnet flux and supporting cap creates the same function
as ball bearing, therefore, no matter how the fan is placed, no slanting
and wobbling occured, which means it's suitable for design in portable
- Vapo bearings are made of a material specially treated for wear-resistance
and impact-resistance. When used in conjunction with the MagLev, it
creates a spring function, which helps the fan motor to bear impact.
- Vapo bearing with MagLev is capable of an operating temperature
of more than 70?. It also performs very well in a low temperature
- The elimination of washer and oil ring may also allow the automatic
production thus brings manufacturing efficiency.
- The stable supply from Sunon prevents the inefficiency of supplying
- The Vapo bearing with MagLev design not only features its good quality
but also its low cost.
- The dust cap prevents dust penetrating into bearing and mixing with
nitride particles to clog the motor, which may result in noise and
slower motor operation.
With the combination of MagLev design and Vapo bearing, all the advantages
of ball and sleeve bearings are maintained, while eradicating all the
- Vapo bearings are made of a material specially treated for wear-resistance
and impact-resistance. When used in conjunction with the MagLev,
it creates a spring function, which helps the fan motor to bear
- MagLev design helps the rotor to rotate evenly in a fixed orbit
within the orbit center without any friction with the bearing
bore.No vibration occurred.
- This new system eliminates the use of oil rings and washers,
thus leaving space for the release of gas occurring during normal
operation. No more clogging problems. Vapo bearing is named after
SUNON MagLev prevents the defects of conventional fans.
||Deficiencies of Traditional Motors
||Sunon MagLev Solution
- Weight of rotor is entirely loaded on to the shaft. Abrasive
rotation between shaft and bearing will result in an irregular
and rough surface on the inner surface of bearing bore. The fan
motor rotation becomes uneven and in turn, causes operational
noise and shortens fan life.
- The oil ring and mylar washer not only results in added friction
area but also blocks the high temperature gases, which if not
released before solidification, would become nitride particles
that, in turn, clog in the gap between shaft and bearing bore
then causing a much slower rotation of rotor and noise.
- Entire weight of rotor is completely attracted by magnetic force
in any mounted position, keeping the motor rotating evenly at
a fixed point and keeping a consistent distance from inner surface
of the bearing. No more traditional rubs and noise occur.
- Oil ring, washer, and lubricant no longer used in MagLev structure.
Hence no more oil leakage or stuck rotor problems.
- MagLev design allows an operating temperature higher than 70°C.
- When the fan motor is operating, the steel balls inside will
generate a higher rotational noise than that of a sleeve bearing.
- The construction of Ball bearings is quite weak and unable to
absorb external impact. It is easily damaged and results in louder