Patent Description:
Bicycles were prevalent in many places. With the changes in lifestyles, the environmental awareness and the concept of physical fitness, bicycles are popularly used in daily lives. With development of technology, electric bicycles have been a booming trend, especially in cities. The electric bicycles can be roughly classified into types with hub motor and mid-mounted motor. The advantages of the type with hub motor are that it is compact and artistic in appearance, that the appearance of the bicycle is concise, that the price is low, that there is relatively lower level of requirement for the bicycle frame, and that there is relatively lower requirement for the chain, so the electric bicycles are popular around the world. <CIT>, <CIT> and <CIT> disclose the like electric bicycles.

However, the above-mentioned wheel hub motor has a complicated structure, many parts and components are interconnected, and it is difficult and time-consuming to dismantle and replace. Therefore, it needs a repairer who knows specific model of the wheel hub motor well to repair and/or replace the parts and components, which is inconvenient.

The present invention is, therefore, arisen to obviate or at least mitigate the above-mentioned disadvantages.

The main object of the present invention is to provide an electric wheel hub which can greatly simplify the difficulty of maintenance and/or replacement.

To achieve the above and other objects, an electric wheel hub is provided, including: a shell, including a base and a cover, the base defining an interior space and a mounting entrance, the cover being mounted to the base in a mounting direction and covering the mounting entrance; a motor assembly, including a stator, a rotor and a shaft, the stator and the rotor being received within the shell by moving through the mounting entrance in the mounting direction, the stator and the rotor being relatively rotatable, the rotor being connected with the shell, the shaft being disposed within the shell in a direction opposite to the mounting direction and disposed through and connected with the stator, two ends of the shaft being configured to be respectively connected to two fork arms, the shaft defining an axial direction and a circumferential direction, the shaft and the stator being relatively movable in the axial direction, the shaft and the stator being relatively non-rotatable in the circumferential direction; and a battery unit, electrically connected with the motor assembly, including a cartridge and a plurality of batteries, the plurality of batteries being positionally received within the cartridge, the cartridge being received within the interior space by moving through the mounting entrance in the mounting direction, the cartridge being connected with the stator and disposed around the motor assembly.

The present invention will become more obvious from the following description when taken in connection with the accompanying drawings, which show, for purpose of illustrations only, the preferred embodiment(s) in accordance with the present invention.

Please refer to <FIG> for a preferable embodiment of the present invention. An electric wheel hub of the present invention includes a shell <NUM>, a motor assembly <NUM> and a battery unit <NUM>.

The shell <NUM> includes a base <NUM> and a cover <NUM>, the base <NUM> defines an interior space <NUM> and a mounting entrance <NUM>, and the cover <NUM> is mounted to the base <NUM> in a mounting direction <NUM> and covers the mounting entrance <NUM>. The motor assembly <NUM> includes a stator <NUM>, a rotor <NUM> and a shaft <NUM>, the stator <NUM> and the rotor <NUM> are received within the shell <NUM> by moving through the mounting entrance <NUM> in the mounting direction <NUM>, the stator <NUM> and the rotor <NUM> are relatively rotatable, and the rotor <NUM> is connected with the shell <NUM>. The shaft <NUM> is disposed within the shell <NUM> in a direction opposite to the mounting direction <NUM> and disposed through and connected with the stator <NUM>, and two ends of the shaft <NUM> is configured to be respectively connected to two fork arms <NUM>. The shaft <NUM> defines an axial direction <NUM> and a circumferential direction <NUM>, the shaft <NUM> and the stator <NUM> are relatively movable in the axial direction <NUM>, and the shaft <NUM> and the stator <NUM> are relatively non-rotatable in the circumferential direction <NUM>. The battery unit <NUM> is electrically connected with the motor assembly <NUM>, includes a cartridge <NUM> and a plurality of batteries <NUM>, the plurality of batteries <NUM> are positionally received within the cartridge <NUM>, the cartridge <NUM> is received within the interior space <NUM> by moving through the mounting entrance <NUM> in the mounting direction <NUM>, and the cartridge <NUM> is connected with the stator <NUM> and disposed around the motor assembly <NUM>.

The shaft <NUM> can be mechanically detached from the stator <NUM> so that the wheel hub can be quickly detached or installed without dismantling parts in the motor assembly <NUM>, which is easy to uninstall/install and lowers the repairing cost. The battery unit <NUM> is made to be integral so that it is easy to install and maintain and is stable. In other embodiments, the battery unit <NUM> may be provided without the cartridge <NUM>. The cartridge <NUM> is preferably made of plastic material (such as ABS-PC material) which is of good insulation.

The battery unit <NUM> further includes an attachment portion <NUM>, the cartridge <NUM> is annular and includes a receiving space <NUM>, the attachment portion <NUM> is connected with cartridge <NUM> and extends from a first end <NUM> of the receiving space <NUM>, the motor assembly <NUM> is received within the receiving space <NUM> by moving into the receiving space <NUM> from a second end <NUM> of the receiving space <NUM>, the first end <NUM> is more adjacent to the cover <NUM> than the second end <NUM>, and the attachment portion <NUM> is connected with the stator <NUM>. A circuit board <NUM> is detachably positioned to a side of the attachment portion <NUM> facing toward the cover <NUM>. As the cover <NUM> is removed, the circuit board <NUM> is exposed, so that it is easy to inspect, maintain and/or repair. Preferably, the attachment portion <NUM> and the circuit board <NUM> are non-protrusive beyond the receiving space <NUM> so that an external impact can merely impact the shell <NUM> but cannot impact the circuit board <NUM>, which is stable and durable.

Preferably, an outer circumferential wall of the cartridge <NUM> includes a plurality of openings <NUM> distanced from an inner circumferential wall of the shell <NUM>. The cartridge <NUM> can be taken out from the plurality of openings <NUM>, which helps to replace the cartridge <NUM>.

Preferably, the plurality of batteries <NUM> are partially exposed from the plurality of openings. The plurality of batteries <NUM> can be observed from the plurality of openings <NUM>, which helps to evaluate conditions of the plurality of batteries <NUM>.

The shaft <NUM> further includes an axle <NUM> and a plurality of first engaging portions <NUM>, and the plurality of first engaging portions <NUM> are separately arranged on the axle <NUM> in the circumferential direction <NUM>. The stator <NUM> includes a perforation <NUM> and a plurality of second engaging portions <NUM>, the plurality of second engaging portions <NUM> are separately arranged around the perforation <NUM> in the circumferential direction <NUM>, the axle <NUM> is disposed through the perforation <NUM>, the plurality of first engaging portions <NUM> and the plurality of second engaging portions <NUM> are engaged with each other, one of each said first engaging portion <NUM> and each said second engaging portion <NUM> is a first groove, and the other of each said first engaging portion <NUM> and each said second engaging portion <NUM> is a first rib, so that the shaft <NUM> can be removed in advance for simplifies the detachment and so that the shaft 23and the stator <NUM> are not relatively rotatable and can be easily and accurately assembled.

Preferably, the shaft <NUM> further includes a third engaging portion <NUM>, the stator <NUM> further includes a fourth engaging portion <NUM>, and the third engaging portion <NUM> and the fourth engaging portion <NUM> are engaged with each other. One of the third engaging portion <NUM> and the fourth engaging portion <NUM> is a second groove, and the other of the third engaging portion <NUM> and the fourth engaging portion <NUM> is a second rib. The second groove is not identical to the first groove, and the second rib is not identical to the first rib, so that the shaft <NUM> and the stator <NUM> can be easily and accurately assembled.

The electric wheel hub further includes two end caps <NUM>, the two end caps <NUM> are detachably disposed respectively around opposing ends of the shaft <NUM>, and the shaft <NUM> is hollow and configured for a spindle <NUM> to be disposed therethrough. The shaft <NUM> which is hollow can lower the weight and increase compatibility for the spindle <NUM>. For example, various types of end caps can be used to receive various types of the spindles (having respective diameters of <NUM>, <NUM> and <NUM>, for example). Specifically, each of the opposing ends of the shaft <NUM> includes a first positioning portion <NUM>, each of the two end caps <NUM> includes a second positioning portion <NUM>, and the second positioning portion <NUM> and the first positioning portion <NUM> are engaged with each other so as to provide stable and accurate combination of the two end caps <NUM> and the shaft <NUM>. One of the first positioning portion <NUM> and the second positioning portion <NUM> is a projection, and the other of the first positioning portion <NUM> and the second positioning portion <NUM> is a recess.

Specifically, the electric wheel hub further includes a first bearing <NUM> and a second bearing <NUM>. The cover <NUM> includes a first through hole <NUM>, the base <NUM> includes a second through hole <NUM>, the first bearing <NUM> is received in the first through hole <NUM>, the second bearing <NUM> is received in the second through hole <NUM>, and the shaft <NUM> is disposed through the first bearing <NUM> and the second bearing <NUM> and protrusive out beyond opposing sides of the shell <NUM>. The shaft <NUM> further includes a first end portion <NUM>, a connection portion <NUM>, a flange <NUM> and a second end portion <NUM> in sequence. The first end portion <NUM> is disposed through the first bearing <NUM> and the cover <NUM>, the second end portion <NUM> is disposed through the second bearing <NUM> and the base <NUM>, the connection portion <NUM> includes the plurality of first engaging portions <NUM>, and the connection portion <NUM> is connected with the stator <NUM>. An intersection of the connection portion <NUM> and the first end portion <NUM> includes a stepped portion <NUM>, the first bearing <NUM> is abutted against the cover <NUM> and the stepped portion <NUM> in the axial direction <NUM>, and the second bearing <NUM> is abutted between the base <NUM> and the flange <NUM> between so as to improve stability of the first bearing <NUM> and the second bearing <NUM>.

Since the shaft <NUM> is detachably connected to the stator <NUM>, the first bearing <NUM> and the second bearing <NUM> do not have to be detached as the shaft <NUM> is removed, which avoids loss of the first bearing <NUM> and the second bearing <NUM>, and simplifies the detachment process. To replace the first bearing <NUM> or the second bearing <NUM>, the motor assembly <NUM> does not have to be detached, which is easy and convenient.

An electronic control unit <NUM> is positioned to the shaft <NUM> and located at a side of the base <NUM> opposite to the cover <NUM>, so that the electronic control unit <NUM> can be individually replaced without dismantling the shell <NUM>, which is easy and convenient.

A method of disassembling the electric wheel hub is further provided. The method includes following steps.

In sum, in the design of the electric wheel hub, the maintenance and/or replacement frequency and difficulty of different components are taken into account, which allows the maintenance and/or replacement to be carried out without dismantling the motor assembly. As a result, it can greatly simplify the difficulty of maintenance and/or replacement.

Claim 1:
An electric wheel hub, including:
a shell (<NUM>), including a base (<NUM>) and a cover, the base (<NUM>) defining an interior space (<NUM>) and a mounting entrance (<NUM>), the cover being mounted to the base (<NUM>) in a mounting direction (<NUM>) and covering the mounting entrance (<NUM>);
a motor assembly (<NUM>), including a stator (<NUM>), a rotor (<NUM>) and a shaft (<NUM>), the stator (<NUM>) and the rotor (<NUM>) being received within the shell (<NUM>) by moving through the mounting entrance (<NUM>) in the mounting direction (<NUM>), the stator (<NUM>) and the rotor (<NUM>) being relatively rotatable, the rotor (<NUM>) being connected with the shell (<NUM>), the shaft (<NUM>) being disposed within the shell (<NUM>) in a direction opposite to the mounting direction (<NUM>) and disposed through and connected with the stator (<NUM>), two ends of the shaft (<NUM>) being configured to be respectively connected to two fork arms (<NUM>), the shaft (<NUM>) defining an axial direction (<NUM>) and a circumferential direction (<NUM>), the shaft (<NUM>) and the stator (<NUM>) being relatively movable in the axial direction (<NUM>), the shaft (<NUM>) and the stator (<NUM>) being relatively non-rotatable in the circumferential direction (<NUM>); and
a battery unit (<NUM>), electrically connected with the motor assembly (<NUM>), including a cartridge (<NUM>) and a plurality of batteries (<NUM>), the plurality of batteries (<NUM>) being positionally received within the cartridge (<NUM>), the cartridge (<NUM>) being received within the interior space (<NUM>) by moving through the mounting entrance (<NUM>) in the mounting direction (<NUM>), the cartridge (<NUM>) being connected with the stator (<NUM>) and disposed around the motor assembly (<NUM>)
characterized in that:
the battery unit (<NUM>) further includes an attachment portion (<NUM>), the cartridge (<NUM>) is annular and includes a receiving space (<NUM>), the attachment portion (<NUM>) is connected with cartridge (<NUM>) and extends from a first end (<NUM>) of the receiving space (<NUM>), the motor assembly (<NUM>) is received within the receiving space (<NUM>) by moving into the receiving space (<NUM>) from a second end (<NUM>) of the receiving space (<NUM>), the first end (<NUM>) is more adjacent to the cover (<NUM>) than the second end (<NUM>), and the attachment portion (<NUM>) is connected with the stator (<NUM>).