Hybrid drive for an electric bicycle

Patent metadata

Field	Value
Publication number	US-9758212-B2
Application number	US-200913139496-A
Country	US
Kind code	B2
Filing date	Oct 30, 2009
Priority date	Dec 11, 2008
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

A bicycle includes an electrical auxiliary drive, including an electric motor, a battery for storing electrical energy, which battery is connected to the electric motor, a crank mechanism having pedal cranks, which are mounted on a pedal crankshaft disposed about a crank axis, so as to be able to rotate, and a planetary gear for driving the bicycle both by the electric motor and by the muscle power of a driver, the planetary gear and the electric motor being disposed about the pedal crankshaft of the crank mechanism.

First claim

What is claimed is:

1. A bicycle having an electrical auxiliary drive, comprising:
a drive and gear unit, including:
an electric motor;
a battery adapted to store electrical energy and connected to the electric motor;
a crank mechanism having pedal cranks affixed on a pedal crankshaft, which is rotatably disposed about a crank axis; and
a planetary gear adapted to drive the bicycle both by the electric motor and by muscle power of a driver;
wherein the electric motor is the only electric motor of the electrical auxiliary drive;
wherein the planetary gear and the electric motor are disposed around the pedal crankshaft of the crank mechanism;
wherein the planetary gear includes a planet carrier and planet wheels disposed on the planet carrier such that the planet carrier and the electric motor are axially spaced, and the pedal crankshaft is fixedly connected to the planet carrier;
wherein the planetary gear includes a ring gear such that a chain is positioned on external teeth of the ring gear,
wherein the electric motor and the planetary gear are disposed jointly in a substantially centered and low mounted position on the bicycle in a region of the crank mechanism, so as to cause a center of gravity of the bicycle to be shifted away from a drive wheel, and
wherein the drive and gear unit is arranged in a compact manner, in which a planetary axis of the planetary gear and a motor axis of the electric motor, both of which are disposed along a crank axis of the crank mechanism, so that the planetary gear is connected to the crank mechanism on one side of the crank mechanism and to the electric motor on another side of the crank mechanism, so as to provide a low center of gravity of the drive and gear unit below the driver;
wherein the electric motor is connected to a sun gear of the planetary gear via a hollow shaft, and the pedal crankshaft is disposed in the hollow shaft, and
wherein the electric motor includes a rotor which is fixedly connected to the hollow shaft, which is fixedly connected to a sun wheel of the planetary gear, wherein the pedal crankshaft is routed through the hollow shaft and fixedly connected to the planet carrier of the planetary gear on which the planet wheels are disposed in a manner that enables free rotation, the planet wheels being in engagement with the sun gear and the ring gear, and wherein the ring gear is mounted on the hollow shaft in a freely rotatable manner.

2. The bicycle according to claim 1 , further comprising:
a locking device having a freewheel adapted to lock the rotor of the electric motor.

3. The bicycle according to claim 1 , wherein the bicycle includes at least one of (a) a gear shift mechanism on a drive wheel, (b) a derailleur gear, and (c) a hub gear, the drive wheel being connected to the planetary gear.

4. The bicycle according to claim 1 , further comprising:
a control unit, an rpm sensor on at least one of (a) the planetary gear and (b) a ring gear of the planetary gear, a speed sensor adapted to record a bicycle speed, and an electrical actuator adapted to execute a gear shift operation, the control unit adapted to control the electric motor and the electrical actuator according to a specified control program and in accordance with values of the rpm sensor and the speed sensor.

5. The bicycle according to claim 1 , wherein an rpm sensor is provided on an outer side of the ring gear and is adapted to record a rotational speed of the ring gear.

6. The bicycle according to claim 1 , wherein the pedal crankshaft is fixedly connected to the planet carrier such that when the pedal crankshaft is actuated, the planet wheels are adapted to freely rotate.

7. The bicycle according to claim 6 , wherein the actuation of the pedal crankshaft is compensated by the electric motor.

8. The bicycle according to claim 7 , wherein a speed of the planet wheels and transmission to the ring gear is controlled by the electric motor in conjunction with the planet carrier.

Assignees

• Kimmich Peter
• Kustosch Mario
• Kohlrausch Philipp
• Bosch Gmbh Robert

Inventors

• Kimmich Peter
• Kustosch Mario
• Kohlrausch Philipp

Classifications

• B62M6/55 Primary

  power-driven at crank shafts parts · CPC title

• B62M9/04

  of changeable ratio · CPC title

• B60Y2200/12

  Motorcycles, Trikes; Quads; Scooters · CPC title

• B62M11/145

  built in, or adjacent to, the bottom bracket · CPC title