NL2008181C2

NL2008181C2 - Electric bicycle.

Info

Publication number: NL2008181C2
Application number: NL2008181A
Authority: NL
Inventors: Alfred Thun
Original assignee: Alfred Thun Gmbh & Co Kg
Priority date: 2011-09-28
Filing date: 2012-01-26
Publication date: 2013-10-28
Also published as: TW201313550A; DE202011051464U1; NL2008181A; CN103029798A

Description

Electric bicycle

The invention relates to an electric bicycle, for instance a pedelec or e-bike, at least comprising a drive shaft penetrating at the front, 5 on both sides a drive housing with pedals arranged at its free ends penetrating the drive housing, for driving the bicycle, an electric motor for assisting in pedaling and a motor control unit for controlling the electric motor, said motor control 10 unit securing that the electric motor is in operation only when the electric bicycle is pedaled in the forward direction, the motor control unit being connected by means of cables with a sensor detecting the direction of rotation 15 of a magnet ring arranged on the drive shaft.

Such electric bicycles, also called pedelecs or e-bikes, are becoming increasingly popular with the users .

In such electric bicycles, an electric motor 20 controlled by means of a motor control unit assists the user in pedaling, and it has to be secured that the electric motor is only activated when the bicycle rider pedals in the forward direction .

25 For this purpose, usually sensors are provided, by means of which it is secured that the electric motor can be activated exclusively when pedaling in the forward direction.

Conventionally, in inexpensive variants, this 30 is achieved by a disk attached at the shaft, on which a certain number of magnets are mounted. The magnets mounted on the shaft will move, when the - 2 - shaft is rotated, past a sensor and thus generate a signal that can be received by the sensor. Such magnet disks have the drawback, however, that they are more or less freestanding and are thus exposed 5 to dirt, high-pressure washing, inadvertent displacement or similar slip out of position, which therefore affects their proper functioning. In a prior art solution, seven magnets are mounted on a disk. This low number of magnets is not 10 sufficient for a reactive motor control unit.

Further, sensor systems are known in the art, which are located in the inner bearing. For this purpose, for instance magnet rings with Hall sensors are used.

15 In such sensor systems arranged inside the inner bearing, it is disadvantageous that on the one hand, because of the cable laid inside the bicycle frame, additional time during assembly is needed, thus the assembly cost being increased, 20 and on the other hand there is a risk of damages, in particular to the cables, during assembly or disassembly as well as the necessity of providing boreholes in the pipes or frame parts of the bicycle, in order to lead the cables out and to 25 connect them for instance with a motor control unit .

Based on the prior art mentioned above, it is the object of the present invention to provide an electric bicycle of the species mentioned above, 30 wherein damages or impairment of the sensor, the magnet ring or the cables, for instance by dirt, high-pressure washing, inadvertent displacement or the like is avoided, which nevertheless can be manufactured economically and simply and has a - 3 - particularly high lifetime and can be assembled and also disassembled quickly and easily.

For achieving this object, the invention proposes that the sensor is arranged in a further 5 housing or a cap, which can be attached at the front side of the drive housing, the cables connecting the sensor with the motor control unit being arranged at the outside of the drive housing and/or at frame parts of the electric bicycle.

10 In such a solution, the sensor can be attached after assembly of the drive housing at the front side thereof, and the cables required for the connection with the motor control unit can be arranged and attached outside at frame parts of 15 the electric bicycle. Thereby that the sensor is located in a further housing or a cap, it is protected as far as possible against external influences, such as for instance dirt, high- pressure washing or similar undesired properties. 20 The cables laid at the outside along frame parts do not require new boreholes in frame parts and are thus not affected by the assembly or disassembly of parts of the drive and by damages caused thereby. Such a sensor can be manufactured 25 economically and easily and can be assembled and also disassembled at an electric bicycle, and further has a particularly long lifetime.

It may particularly be provided that the further housing or the cap with the sensor can be 30 attached or is attached, in particular clamped or locked, at the front side on the drive housing and/or on or at adapters inserted into the drive housing.

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Thereby, the sensor arranged within a further housing or a cap can be attached in a quick and simple way without the need of special tools at existing adapters arranged within the drive 5 housing or directly at the drive housing. Such a clamping or locking solution can quickly be disassembled if needed, and can for instance be re-assembled just as quickly after a maintenance job on the drive.

10 Further, it may particularly be provided that the further housing or the cap is shaped approximately in a pot-like manner and comprises a hole in the bottom of the pot, at or close to the inner surfaces of the hole, if applicable forming 15 the inner surfaces of the hole, the sensor being arranged, the hole and the sensor being penetrated by the drive shaft.

A thus configured housing or cap can be fitted on the drive shaft protruding from the drive 20 housing and then be connected with the drive housing or an adapter inserted into the drive housing, and can be attached thereat.

The sensor is to a high degree covered and protected by parts of the housing or the cap, so 25 that there cannot act nearly any external influences on it.

Furthermore, it may particularly be provided that the further housing or the cap is made of plastic .

30 Making the further housing or the cap of plastic is an economical and also long-life solution .

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Moreover, it may particularly be provided that the sensor is formed by a Hall sensor.

Using a Hall sensor as a sensor has in principle proven effective and represents a long-5 life solution at relatively low cost.

Further, it may particularly be provided that the magnet ring comprises a multitude of poles distributed in the peripheral direction and following each other.

10 Finally, it may particularly be provided that the magnet ring comprises two times sixteen poles.

In particular, the arrangement of two times sixteen poles, which are distributed in the peripheral direction on the magnet ring, permits a 15 reliable detection of the forward movement by the sensor, which is connected with the motor control unit.

An embodiment of the invention is shown in the drawings and is explained in more detail in the 20 following. There are:

Figure 1 a drive housing according to the invention with cap, sensor and magnet ring in an exploded view;

Figure 2 a drive housing according to the 25 invention in the assembled position.

In the Figures, a drive housing 2 of an electric bicycle, such as for instance of a pedelec or of an e-bike, is shown. The drive housing 2 comprises a drive shaft 1 penetrating 30 the drive housing 2 at the front, on both sides - 6 - with pedals (not shown in the Figures) arranged at its free ends penetrating the drive housing 2, for driving the bicycle. Further, the electric bicycle comprises an electric motor (not shown in the 5 Figures) for assisting in pedaling and a motor control unit for controlling the electric motor. The motor control unit secures that the electric motor is only in operation, when the electric bicycle is pedaled in the forward direction. The 10 motor control unit is connected by means of cables 3 with a sensor 4, which detects the direction of rotation of a magnet ring 5 arranged on the drive shaft 1.

According to the invention, the sensor 4 is 15 arranged in a further housing, which in the embodiment is formed by a cap 6. The cap 6 can be attached or is attached at the front side of the drive housing 2 (in Figure 2). The cables 3 connecting the sensor 4 with the motor control 20 unit are arranged outside at the drive housing 2 (as can be seen in Figure 2) and/or at frame parts of the electric bicycle. A sensor 4 thus arranged within a cap 6 is protected in the assembled position to a high degree against external 25 influences such as dirt or water, for instance during high-pressure cleaning, and can be disassembled and also re-assembled if needed without using special tools.

A sensor thus arranged within a cap 6 can 30 economically be manufactured and has a high lifetime .

As can be seen in the Figures, the further housing formed by a cap 6 with the sensor 4 can be fitted at the front on adapters already inserted 35 into the drive housing 2 and can be attached - 7 - thereat. Attachment can be performed by clamping or locking or in a similar re-detachable way.

Alternatively and not shown in the Figures, the cap 6 with the sensor 4 may also be fitted at the 5 front side immediately on the drive housing 2 and attached thereat.

As can in particular be seen in Figure 1, the cap 6 is shaped approximately in a pot-like manner, the bottom of the pot comprising a hole 7.

10 The sensor 4 is arranged close to the inner surfaces of the hole, the hole 7 and the sensor 4 being penetrated by the drive shaft 1 and by a magnet ring 5 arranged on the drive shaft 1 . In the embodiment, the cap 6 is made of plastic, and 15 the sensor 4 is formed by a per se known Hall sensor. Making the cap of plastic and using a per se known Hall sensor as a sensor permits on the one hand an economical manufacture and on the other hand a high lifetime.

20 The magnet ring 5 comprises a multitude of poles distributed in the peripheral direction and following each other. In the embodiment, the magnet ring 5 comprises two times sixteen poles distributed in the peripheral direction.

25 The invention is not limited to the embodiments, but is in many ways variable within the scope of the disclosure.

All novel individual or combined features disclosed in the description and/or drawing are 30 deemed essential for the invention.

Claims

An electric bicycle, for example a pedelec or e-bicycle, at least comprising a drive shaft (1) which penetrates on the front, on both sides, a drive housing (2) and provided with pedals arranged on the free drive housing ( 2) protruding ends, for driving the bicycle, an electric motor to assist pedaling and a motor control unit for controlling the electric motor, said motor control unit ensuring that the electric motor only works when the electric bicycle is pedaled in the forward direction, the motor control unit is connected by cables (3) to a sensor (4) which detects the direction of rotation of a magnetic ring (5) mounted on the drive shaft (1), characterized in that the sensor (4) is arranged in a further housing or cap (6), which can be attached to the front of the drive housing (2), the cables (3) connecting the sensor (4) to the motor control unit being connected mounted on the outside of the drive housing (2) and / or on frame parts of the electric bicycle.

An electric bicycle according to claim 1, characterized in that the further housing or cap (6) can be attached to or attached to the sensor housing (2) with the sensor (4), in particular clamped or fixed ) and / or on the adapters inserted in the drive housing (2).

An electric bicycle according to claim 1 or 2, characterized in that the further housing or cap (6) is approximately formed in a pot-like manner and comprises a hole in the bottom of the pot (7), and at or near the inner sides of the hole, which possibly form the inner surfaces of the hole, the sensor (4) is arranged, and wherein the opening (7) and the sensor (4) are penetrated by the drive shaft.

An electric bicycle according to any one of claims 1 to 3, characterized in that the further housing or cap (6) is made of plastic.

An electric bicycle according to any of claims 1 to 4, characterized in that the sensor (4) is formed by a Hall sensor.

An electric bicycle according to any one of claims 1 to 5, characterized in that the magnet ring (5) comprises a plurality of consecutive poles, distributed in circumferential direction.

An electric bicycle according to claim 6, characterized in that the magnet ring (5) has two times sixteen poles.