E-Bike Systems: Center Unit System

Center Unit System design engineers Panasonic
E-Bike Systems: Center Unit System

The center unit system is the most typical E-Bike style. Panasonic released this "Mid-ship-design" as an own complete E-Bike in Japan 1996.
This "Mid-ship-design" is used as two different versions to be almost flexible and a real all-round talent for sportive/trekking bikes as well for city bikes.

One of the major advantages is the weight balance, which is almost close to normal bicycles. Also the low center of gravity gives stable riding behavior and is a popular feature of this system.

 

 

The rear mount type is the basic design of a center unit system. It has a suitable battery position (so called "upright battery") to realize a deep and comfortable entry for the rider into the bike and still allows enough space for an high capacity battery (up to 648 Wh).    

Further features allow a comfortable usage:               
 - The battery position allows an easy / comfortable removal to charge the battery externally (the battery is made for both charging conditions: built-in or separated from the bike)
 - An extended chain tube based on this motor design, allows a more stable riding behavior    

 

 

Rear mount type:

Motor Unit (front & rear mount)
Torque Sensor
Battery
Console
Charger

           
The front mount type is also a design for the Panasonic center unit system. It was developed as an ideal adjustment to the more aggressive frame structure of sportive bikes. The motor design is specifically made to change the battery location to the down tube of the bike frame. 

Based on this change a shorter chain tube then for normal bikes is used, which has two positive effects especially in terms of an adjustment to the more sportive use:       
 - A more agile riding behavior and performance by riding curves                      
 - A shortened total length of the bike (compared to rear mount type)    

 

 

 

Front mount type:

Motor Unit (front)
Torque Sensor
Battery
Console
Charger
 


Center Unit System - Multi Speed Assist System   !NEW!

This new motor is the beginning of a new flexibilty for using  electric power  within compact assist systems.

This new system combines the advantages from the well known "One Axle Motor Unit"  with an internal gear box technology, to provide a new feeling for riding a high quality pedelec.

The User is able to choose between two different gears as it  is known from outer chain shifting systems, but less leaping chain due to one sprocket.

Especially  for the new trend of E-MTB's it's a suitable way to reduce the sound level and provide always stable riding behaviour by adjustment of motor torque during shift change.

It's also able to reduce the deterioration of the chain and other transmission parts (which are direct in touch with the chain) during the use of smaller gear ratios (e.g. by riding uphill). Because the chain is still using same size of big front sprocket with relatively long circulation length, which supports a well harmonized force sharing at the chain.

     


Center Unit System - Rear Mount Motor Unit

The motor unit is the main device with the most influence to perceive the power as assistance on an E-Bike. The "one-axle"-type provides the assist power directly to the big chain wheel (41 teeth steel chain wheel).

There are several improvements compared to the established "two-axle"-type:
- Large chain wheel (41 teeth) which provides the motor power to the chain and has an improved power transmission and reduces the attrition of the chain and the chain wheel
- Reduced amount of parts which are involved to any force and need to be serviced

This new motor is the beginning of a new flexibilty for using  electric power  within compact assist systems.

This new system combines the advantages from the well known "One Axle Motor Unit"  with an internal gear box technology, to provide a new feeling for riding a high quality pedelec.

The User is able to choose between two different gears as it  is known from outer chain shifting systems, but less leaping chain due to one sprocket.

Especially  for the new trend of E-MTB's it's a suitable way to reduce the sound level and provide always stable riding behaviour by adjustment of motor torque during shift change.

It's also able to reduce the deterioration of the chain and other transmission parts (which are direct in touch with the chain) during the use of smaller gear ratios (e.g. by riding uphill). Because the chain is still using same size of big front sprocket with relatively long circulation length, which supports a well harmonized force sharing at the chain.


Center Unit System - Front Mount Motor Unit

The front-mount-version has the same structure inside as the rear mount. Only the outside body is turned about 180° by an adjusted shape. Therefore there are the same advantages compared to the established "two-axle"-system like the "rear-mount"-type.

 

 

 


Our single gear center motor units are compatible for the use of electric shifting from Shimano (Di2 of internal system) with gear indication at the Panasonic display and power supply from the Panasonc battery.


Torque Sensor

The high-precision torque sensor is responsive to changes in pedal power when starting, climbing or accelerating. A detector coil measures pedaling torque and sends an output power signal to the controller. This kind of technology allows measurement of the pedaling torque without contact of the axle, therefore without energy loss as well.

 

 

 

 

 

 


Center Unit System - Upright Battery (36 V)

The upright battery is the traditional and the most common battery type in the Panasonic E-Bike history. 

Ideal for "Mid-ship-design": 
- enough space for high capacity
- easy position to handle

 


Center Unit System - Triangle Battery (36 V)

The triangle battery for the center motor unit was newly developed in 2013. The position and design is a typical one to correspond with the sporty type of E-Bikes, well more than the upright  type of battery, due to the shorter total bicycle length. 

 

 

 


Center Unit System -  Integrated Design Battery    !NEW!

Our new integrated design battery technology applies each bike a more sportive, light, smooth and clean design. Based on the side clip architecture the battery is easy to implement to nearly each kind of frame design, whether female or male, hardtail or full suspension. Even to plug in or take out the battery is very easy from user point of view, because of applying this archtiecture

(Shape and dimension of integrated design battery at the picture is just a design study and needs to be adjusted regarding the demand of each bike manufacturer)


Console

The center LCD console separates the display and operation buttons for easy visibility and usage. This console is designed to be visible even in strong sunlight, and tough enough to withstand rain, wind and dust. (IPX5)

Properties: Clock / Micro USB Port / Center Display / Removable Display
Separate buttons / Walk-Assistance Button / IPX5 / 10 Language Indication / Speed / Average Speed / Max. Speed / Riding Distance / Total Riding Distance / Rest Riding Distance / Battery Charge Level / Assist Power indicator / Back light

 

Other types

Side LCD type
This display type has the same properties and functions like the center version, but the operation buttons are integrated. 

Properties: Micro USB Port / Walk-Assistance Button / 10 Language Indication / Speed / Average Speed / Max. Speed / Riding Distance / Total Riding Distance / Rest Riding Distance / Battery Charge Level / Assist Power indicator / Back light

Side LED type
Functional design for simple indication and function

Properties:
Micro USB Port / Walk-Assistance Button / Battery Charge Level / Back light

 

 


36 V Charger - Center Motor Unit

This charger provides the same high quality in terms of efficiency and charging-safety as our high capacity battery technology. When the charging starts, a communication between the battery and the charger ensures a safe and optimized control of the electric current flow. For safety reasons there is no fan and no vent hole for protection from dust and moisture. 
- Charging on E-Bike is possible
- Indoor usage only