Motorized mid-drive unit

Patent metadata

Field	Value
Publication number	US-12428102-B2
Application number	US-202217748442-A
Country	US
Kind code	B2
Filing date	May 19, 2022
Priority date	May 19, 2021
Publication date	Sep 30, 2025
Grant date	Sep 30, 2025

Abstract

A vehicle may include a pedal assembly, a motor assembly, and a drive unit that may be used to allow selective usage of one or both of the pedal assembly and the motor assembly to convey power to a driven wheel of the vehicle. The drive unit can include a gearbox that may enclose components which form at least part of a first power path between the pedal assembly and the driven wheel and a second power path between the motor assembly and the driven wheel. The first and second power paths can converge at a component within the gearbox. One-way bearings at points in the first and second power paths prior to the convergence of the power paths can inhibit or prevent the pedal assembly from being affected by operation of the motor assembly, and vice versa.

First claim

What is claimed is:

1. A gearbox adapted for use on a mid-drive e-bike, the e-bike having footpedals and a driven wheel, the gearbox comprising:
an electric motor;
a plurality of gears;
a first one-way bearing that is coaxial with a first axis of rotation; and
a second one-way bearing that is coaxial with a second axis of rotation, the second axis of rotation being spaced apart from the first axis of rotation;
the first one-way bearing configured to enable power from the electric motor to be delivered to the driven wheel;
the second one-way bearing configured to enable power from the footpedals to be delivered to the driven wheel; and
the gearbox configured to enable a user to propel the e-bike with: the footpedals alone, with the electric motor alone, and simultaneously with the footpedals and the electric motor.

2. The gearbox of claim 1 , wherein the gearbox includes a chain wheel configured to receive power from the electric motor and the footpedals and deliver the power to the driven wheel via a chain.

3. The gearbox of claim 2 , additionally comprising a bottom bracket shaft rotationally coupled to the footpedals, wherein the chain wheel is rotationally coupled to an output gear supported the bottom bracket shaft.

4. The gearbox of claim 3 , wherein the output gear is conditionally rotationally coupled to the bottom bracket shaft by the second one-way bearing.

5. The gearbox of claim 3 , wherein the output gear is supported on the bottom bracket shaft by a rotary bearing which allows the output gear to rotate independent of the bottom bracket shaft when no power is being provided via the footpedals.

6. The gearbox of claim 2 , wherein the plurality of gears comprise an intermediate step gear set forming part of a motor power path from the electric motor to the chain wheel.

7. The gearbox of claim 6 , wherein the intermediate step gear set comprises an upper step gear set conditionally rotationally coupled to a lower step gear set by the first one-way bearing.

8. The gearbox of claim 1 , wherein the gearbox forms part of a mid-drive unit axially offset from an axis of rotation of the driven wheel.

9. A bicycle, comprising:
a frame;
a driven wheel supported by the frame;
a pedal assembly having a bottom bracket shaft configured to rotate about a pedal axis;
an electric motor; and
a gearbox supported by the frame, the gearbox comprising:
a first one-way bearing forming part of a motor power path between the electric motor and an output gear operably coupled to the driven wheel to deliver power to the driven wheel, the first one-way bearing being coaxial with the pedal axis; and
a second one-way bearing forming part of a pedal power path between the pedal assembly and the output gear, the second one-way bearing being offset from the pedal axis.

10. The bicycle of claim 9 , wherein the pedal assembly further comprises:
first and second pedal cranks rotationally coupled to the bottom bracket shaft at respective ends of the bottom bracket shaft.

11. The bicycle of claim 10 , wherein the output gear is supported on the bottom bracket shaft by the second one-way bearing.

12. The bicycle of claim 10 , wherein the output gear is supported on the bottom bracket shaft by a rotary bearing, the gearbox additionally comprising a pedal output gear supported on the bottom bracket shaft by the second one-way bearing.

13. The bicycle of claim 12 , wherein the first one-way bearing supports a motor transfer gear on an intermediate shaft axially offset from the bottom bracket shaft, the motor transfer gear operably connected to the electric motor.

14. The bicycle of claim 13 , wherein the intermediate shaft is rotationally coupled to a first offset gear engaged with the pedal output gear and a second offset gear engaged with the output gear.

15. The bicycle of claim 13 , wherein the motor transfer gear is operably connected to the electric motor by an intermediate step gear set supported by a step gear shaft.

16. A gearbox configured to be secured to a bicycle frame, the gearbox comprising:
a chain wheel configured to engage a chain of the bicycle to deliver power to a drive wheel of the bicycle via a chain;
a bottom bracket shaft configured to receive power from a pedal assembly of the bicycle and to rotate about a pedal axis of rotation;
a step gear configured to receive power from an electric motor and to rotate about a step gear axis of rotation;
a first one-way bearing forming part of a pedal power path between at least the bottom bracket shaft and an output gear operably coupled to the chain wheel, the first one-way bearing coaxial with the pedal axis of rotation; and
a second one-way bearing forming part of a motor power path between at least the step gear and the output gear operably coupled to the chain wheel, the second one-way bearing coaxial with the step gear axis of rotation.

17. The gearbox of claim 16 , wherein the output gear is supported on the bottom bracket shaft by the first one-way bearing.

18. The gearbox of claim 16 , wherein the first one-way bearing and the output gear are supported on the bottom bracket shaft at different locations along the bottom bracket shaft.

19. The gearbox of claim 16 , wherein the step gear is supported on a step gear shaft by the second one-way bearing.

20. The gearbox of claim 16 , additionally including the electric motor, the electric motor located at least partially within a housing of the gearbox.

Assignees

• Razor Usa Llc

Inventors

• Chen Robert
• Wang Yau
• Lu Louis

Classifications

• B62M3/003

  Combination of crank axles and bearings housed in the bottom bracket (bottom bracket frame details B62K19/34) · CPC title

• B62K19/34

  Bottom brackets · CPC title

• B62M11/06

  with spur gear wheels (B62M11/14 takes precedence) · CPC title

• B62M11/145

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

• F16H37/0826

  with only one output shaft · CPC title