Patent Description:
A general internal transmission mechanism uses a centrifugal force to achieve automatic transmission, a centrifugal block is swung out to achieve automatic up shift when a certain pedal frequency is reached, and the centrifugal block is retracted to achieve automatic downshift when the pedal frequency is reduced to a transmission point or below, as described in <CIT>.

<CIT> discloses a hub motor and inner variable-speed hub integrated device, including a main shaft, where in the main shaft is respectively sleeved with an inner variable-speed hub and a hub motor, the inner variable-speed hub is provided with an end cover, and the hub motor includes a winding stator, a rotor, a sun gear, a motor clutch, an internal ring gear and a hub, and the inner variable-speed hub adopts a centrifugal inner variable-speed hub, which can automatically realize speed regulation according to a rotating speed of a flywheel. The centrifugal variable-speed hub uses a centrifugal force to achieve automatic transmission, and a centrifugal block is swung out to achieve automatic up shift when a certain pedal frequency is reached, and the centrifugal block is retracted to achieve automatic downshift when the pedal frequency is reduced to the transmission point or below.

However, for a vehicle employing the hub motor and inner variable-speed hub integrated device described above, when the vehicle is running at a high speed (greater than the transmission point), if a rider does not want to pedal, or does not need to pedal when going downhill, the inner variable-speed hub is automatically downshifted due to a decrease in rider's pedal frequency; when the vehicle remains at a high speed (greater than the transmission point) after sliding for a certain distance, it takes a short time for the pedal frequency to reach the transmission point after the rider pedals again to automatically up shift the inner variable-speed hub. In this case, the automatic downshift of the inner variable-speed hub will affect the riding experience, and an increase in gear shifting frequency tends to cause failure of the inner variable-speed hub, affecting its service life.

<CIT> discloses a hub motor falling within the wording of the precharacterizing portion of claim <NUM>.

In view of the shortcomings existing in the prior art, an objective of the present invention is to provide a hub motor having an integrated transmission mechanism, which realizes automatic shifting of gears according to an output speed, and can reduce the gear shifting frequency, prolong the service life and improve the riding experience.

The above mentioned objects are achieved by the invention as claimed in claim <NUM>. The latter defines a hub motor for which protection is sought. The dependent claims concern particular embodiments of the invention as claimed in claim <NUM>.

In summary, the present invention has the following beneficial effects:.

In the drawings: <NUM>, main shaft; <NUM>,hub; <NUM>, end cover; <NUM>, planet carrier; <NUM>, gear plate; <NUM>, planet wheel; <NUM>, sun gear; <NUM>, ring gear; <NUM>, second protrusion; <NUM>, first clutching assembly; <NUM>, pawl seat; <NUM>, pawl; <NUM>, ratchet wheel; <NUM>, first protrusion; <NUM>, positioning plate; <NUM>, avoidance settling tank; <NUM>, centrifugal block; <NUM>, shaft rod; <NUM>, torsion spring; <NUM>, pin; <NUM>, swing arm; <NUM>, driving rod; <NUM>, limit plate; <NUM>, release slot; <NUM>, driving hole; <NUM>, first bearing; <NUM>, second bearing; <NUM>, third bearing; <NUM>, stator-rotor assembly; and <NUM>, deceleration assembly; <NUM>, ring plate.

The present invention will be described in further detail below with reference to the accompanying drawings.

This specific embodiment is merely illustrative of the present invention and is not intended to limit the present invention.

A hub motor having an integrated transmission mechanism, referring to <FIG>, includes a main shaft <NUM>, wherein the main shaft <NUM> is provided with a hub <NUM> and an end cover <NUM> which are connected to each other, and the hub <NUM> and the end cover <NUM> are connected by screws for outputting a rotation speed; a machine core assembly connected to the hub <NUM> and a transmission mechanism connected to the end cover <NUM> are each disposed on the main shaft <NUM>, and in this embodiment, a pedal rotation speed can be input through the transmission mechanism to drive the end cover <NUM> and the hub <NUM> to rotate, driving a vehicle to move forward, while the machine core assembly can input a motor rotation speed to drive the hub <NUM> and the end cover <NUM> to rotate, assisting the vehicle to move forward; the transmission mechanism includes a centrifugal drive assembly, and the centrifugal drive assembly is connected to the end cover <NUM>, and switches states according to the rotation speed of the end cover <NUM>; and according to the hub motor in this embodiment, the state of the centrifugal drive assembly, not the pedal frequency, is changed according to the output speed of the hub <NUM> and the end cover <NUM>, thereby being able to reduce the gear shifting frequency of the transmission mechanism, prolong the service life, and improve the riding experience.

Referring to <FIG>, in this embodiment, the machine core assembly includes a stator-rotor assembly <NUM> and a deceleration assembly <NUM>, and a rotation speed of a rotor of the stator-rotor assembly <NUM> is input to the hub <NUM> after passing through the deceleration assembly <NUM>, forming a gear motor structure; and in this embodiment, the deceleration assembly <NUM> is a planetary deceleration assembly including a sun gear <NUM> connected to a rotor, a planet carrier <NUM> sleeving the main shaft <NUM>, and an internal ring gear <NUM> is connected to the hub <NUM>, and the planet carrier <NUM> is provided with a planet wheel <NUM> which is meshed with the sun gear <NUM> and the internal ring gear <NUM>; wherein the planet carrier <NUM> belongs to the prior art and will not be described in detail herein.

Referring to <FIG>, the centrifugal drive assembly includes centrifugal blocks <NUM>, each centrifugal block <NUM> is provided with a shaft rod <NUM> connected to the end cover <NUM> in a penetrating manner, and the centrifugal blocks <NUM> can rotate about the shaft rods <NUM>; the centrifugal blocks <NUM> can be switched from a retracted state to a swing-out state according to the rotation speed of the end cover <NUM>; in this embodiment, an inner end wall of the end cover <NUM> is provided with a ring plate <NUM>, an end of the ring plate <NUM> is fixedly provided with a positioning plate <NUM>, and the positioning plate <NUM> is matched with the end cover <NUM> to form a housing of the transmission mechanism; one ends of the shaft rods <NUM> are connected with the positioning plate <NUM>, and the other ends of the shaft rods <NUM> are connected with the end cover <NUM>; and meanwhile, the ring plate <NUM> is located on outer sides of the centrifugal blocks <NUM>, and can play a radial limiting role on the centrifugal blocks <NUM>, i.e., the centrifugal blocks <NUM> cannot continue to rotate after being in contact with an inner side wall of the ring plate <NUM>; and in this embodiment, one ends of the shaft rods <NUM> are directly connected to the end cover <NUM>, while the inner end wall of the end cover <NUM> extends to form the ring plate <NUM>, and in other alternative embodiments, a mounting base may be fixedly connected to the inner end wall of the end cover <NUM>, the end of the shaft rods <NUM> are connected to the mounting base, and at the same time, the mounting base radially limits the centrifugal blocks <NUM>.

Referring to <FIG>, in this embodiment, the positioning plate <NUM> and the ring plate <NUM> are connected by screws, and at the same time, an end of the inner sidewall of the ring plate is provided with a clamping groove matched with the positioning plate <NUM>, and the positioning plate <NUM> can be limited axially and radially by the clamping groove, thereby ensuring the assembly accuracy; in this embodiment, the number of the centrifugal blocks <NUM> is two, and the centrifugal drive assembly further includes an elastic reset member connected to only one centrifugal block <NUM> thereof; in this embodiment, the elastic reset member is a torsion spring <NUM>, and the elastic force of the torsion spring <NUM> causes the centrifugal blocks <NUM> to have a tendency to reset to the retracted state; and specifically, the torsion spring <NUM> sleeves the shaft rod <NUM>, one end of the torsion spring <NUM> is connected to the centrifugal blocks <NUM>, and the other end of the torsion spring <NUM> is connected to the positioning plate <NUM>.

Referring to <FIG>, the transmission mechanism further includes a planet carrier <NUM>, a sun gear <NUM> fixedly disposed on the main shaft <NUM>, and a ring gear <NUM>, and the planet carrier <NUM> is provided with a planet wheel <NUM> which is meshed with the sun gear <NUM> and the ring gear <NUM>; a first clutch assembly <NUM> is arranged between the planet carrier <NUM> and the end cover <NUM>, and a second clutch assembly is arranged between the ring gear <NUM> and the positioning plate <NUM>; the centrifugal drive assembly controls transmission between the ring gear <NUM> and the positioning plate <NUM> by limiting or releasing the second clutch assembly; specifically, in this embodiment a second bearing <NUM> is arranged between the planet carrier <NUM> and the end cover <NUM>, a third bearing <NUM> is arranged between the ring gear <NUM> and the end cover <NUM>, and two first bearings <NUM> are arranged between the main shaft <NUM> and the planet carrier <NUM>; the planet carrier <NUM> is provided with a gear plate <NUM> circumferentially linked thereto, and a pedal rotation speed is input by driving the planet carrier <NUM> to rotate through the gear plate <NUM>; in this embodiment, shifting of two gears can be realized by using a set of planetary gear assemblies, and in order to achieve shifting of more gears, a plurality of sets of planetary gear assemblies can be connected for transmission; and of course, in other alternative embodiments, the planetary gear assembly may be replaced with other structures, without limitation herein.

Referring to <FIG>, the second clutch assembly includes a pawl seat <NUM>, a pawl <NUM>, a ratchet wheel <NUM> and a spring ring, wherein the pawl seat <NUM> is fixedly connected with an inner end surface of the positioning plate <NUM>, and the ratchet wheel <NUM> and the ring gear <NUM> can be circumferentially linked; the centrifugal drive assembly further includes a limit plate <NUM> connected to the centrifugal blocks <NUM>, and the limit plate <NUM> is provided with a release slot <NUM> matched with the pawl <NUM>; and the limit plate <NUM> can press the pawl <NUM> so that the pawl <NUM> cannot be meshed with the ratchet wheel <NUM>, and after the centrifugal blocks <NUM> are rotated to be swung out, the limit plate <NUM> can be driven to rotate so that the pawl <NUM> is embedded in the release slot <NUM>, and is meshed with the ratchet wheel <NUM>;specifically, when the centrifugal blocks <NUM> are in a retracted state, an inner side wall of the limit plate <NUM> is in contact with the pawl <NUM>, so that a meshing end of the pawl <NUM> cannot bounce up to be meshed with the ratchet wheel <NUM>, and the second clutch assembly cannot be driven under the restriction of the centrifugal drive assembly; after the centrifugal blocks <NUM> is swung out, the limit plate <NUM> is driven to rotate so that the release slot <NUM> is opposite to the pawl <NUM>, and then the meshing end of the pawl <NUM> bounces up and is embedded into the release slot <NUM>, and is meshed with the ratchet wheel <NUM>, so that the second clutch assembly can be driven after being released by the centrifugal drive assembly.

Referring to <FIG> and <FIG>, in this embodiment, the ring gear <NUM> includes two inner circumferential side walls having different inner diameters, one inner circumferential side wall of the ring gear <NUM> is provided with inner teeth matched with the planet wheel <NUM>, and the other inner circumferential side wall of the ring gear 34is uniformly provided with a plurality of second protrusions <NUM>; an outer circumferential side wall of the ratchet wheel <NUM> is uniformly provided with a plurality of first protrusions <NUM>, and the first protrusions <NUM> are in contact with the second protrusions <NUM> to enable the ratchet wheel <NUM> to be circumferentially linked with the ring gear <NUM>, and the linkage between the ratchet wheel <NUM> and the ring gear <NUM> through the first protrusions <NUM> and the second protrusions <NUM> can provide cushioning during gear shifting to improve the riding experience.

Referring to <FIG>, in this embodiment, the centrifugal blocks <NUM> are radially disposed at an outer side of the second clutch assembly, thereby being capable of reducing an axial dimension; each centrifugal block <NUM> is provided with a swing arm <NUM> for driving the limit plate <NUM> to rotate, specifically, each swing arm <NUM> is provided with a driving rod <NUM>, the limit plate <NUM> is provided with driving holes <NUM> matched with the driving rods <NUM>, and each driving hole <NUM> is a waist-shaped hole; the positioning plate <NUM> is provided with an avoidance settling tank <NUM> matched with the swing arms <NUM>, so that the axial dimension can be reduced; the centrifugal blocks <NUM> are connected to the swing arms <NUM> by pins <NUM>, and the positions of the pins <NUM> relative to the centrifugal blocks <NUM> and the swing arms <NUM> in the circumferential direction is fixed, so that the centrifugal blocks <NUM> can drive the swing arms <NUM> to deflect by the pins <NUM>; and after the swing arms <NUM> are deflected, the driving rods <NUM> are in contact with the inner walls of the driving holes <NUM> to drive the limit plate <NUM> to rotate.

The working principle is as follows:
a rotation speed of a pedaling power is transmitted to the gear plate <NUM>, the gear plate <NUM> drives the planet carrier <NUM> to rotate, the sun gear <NUM> is fixed, the planet carrier <NUM> drives the ring gear <NUM> to rotate through the planet wheel <NUM>, and a rotation speed of the ring gear <NUM> is greater than a rotation speed of the planet carrier <NUM>.

In a low gear: the centrifugal blocks <NUM> are in the retracted state, the pawl <NUM> in the second clutch assembly cannot be meshed with the ratchet wheel <NUM> under the restriction of the limit plate <NUM>, and the rotation speed of the ring gear <NUM> cannot be transmitted to the end cover 22through the second clutch assembly; and at this time, the planet carrier <NUM> drives the end cover <NUM> to rotate through the first clutch assembly <NUM> to achieve power output.

In a high gear: after a rotation speed of the end cover <NUM> reaches a transmission point, the centrifugal blocks <NUM> are rotated to the swing-out state under the action of the centrifugal force, and the limit plate <NUM> is driven to rotate by the swing arms <NUM> so that the pawl <NUM> in the second clutch assembly is opposite to the release slot <NUM>; a meshing end of the pawl <NUM> bounces up and is embedded into the release slot <NUM> and is meshed with the ratchet wheel <NUM>, at this time, the second clutch assembly can be driven, and then the rotation speed of the ring gear <NUM> is transmitted to the end cover <NUM> through the second clutch assembly to achieve power output; and at this time, the rotation speed of the end cover <NUM> is greater than the rotation speed of the planet carrier <NUM>, and the first clutch assembly <NUM> is in an overrunning state.

Electric power assistance: after the hub <NUM> and the end cover <NUM> are driven to rotate by the pedaling power, the machine core assembly starts to input a rotation speed to the hub <NUM>,which helps a vehicle to move forward and achieves the purpose of saving labor.

Claim 1:
A hub motor having an integrated transmission mechanism (<NUM>, <NUM>, <NUM>, <NUM>), comprising a main shaft (<NUM>), wherein the main shaft (<NUM>) is provided with a hub (<NUM>) and an end cover (<NUM>) which are connected to each other, a machine core assembly connected to the hub (<NUM>) and the integrated transmission mechanism (<NUM>, <NUM>, <NUM>, <NUM>), which is connected to the end cover (<NUM>), are each disposed on the main shaft (<NUM>), wherein the integrated transmission mechanism (<NUM>, <NUM>, <NUM>, <NUM>) comprises a centrifugal drive assembly, wherein the centrifugal drive assembly is connected to the end cover (<NUM>), and switches states according to a rotation speed of the end cover,
characterized in that,
the centrifugal drive assembly comprises centrifugal blocks (<NUM>), and each centrifugal block (<NUM>) is provided with a shaft rod (<NUM>) connected to the end cover (<NUM>) in a penetrating manner; and the centrifugal blocks (<NUM>) can be switched from a retracted state to a swing-out state according to the rotation speed of the end cover (<NUM>).