Bottom bracket gearshift for an electric bicycle and electric bicycle with such a bottom bracket gearshift
View Patent ↗Presented herein is a bottom bracket gearshift ( 1 ) of an electric bicycle ( 64 ) with an auxiliary drive ( 22 ), in particular in the form of a central motor. The bottom bracket gearshift ( 1 ) has a shift gearbox ( 4 ). In order to make the shift gearbox as small and light as possible, an input stage ( 14 ) is arranged at the transmission input ( 10 ) of the shift gearbox ( 4 ). The input stage ( 14 ) may be arranged between a bottom bracket shaft ( 6 ) and/or the auxiliary drive ( 22 ) and is configured as a transmission into high-speed.
1 . A bottom bracket gearshift for an electric bicycle with an auxiliary drive, comprising:
a bottom bracket shaft, a shift gearbox configured for setting different transmission ratios, and an input stage arranged at a transmission input of the shift gearbox,
wherein the input stage is arranged between the shift gearbox and the bottom bracket shaft and is configured as a speed increasing gear for increasing the rotational speed of the bottom bracket shaft, and wherein the shift gearbox has two or more shift stages which are provided with shifting clutches for shifting different gears of the shift gearbox, and
wherein the input stage comprises a first input gear on a driven side of the input stage on an input shaft of the shift gearbox and a second input gear on a drive side of the input stage coaxial with the bottom bracket shaft, the bottom bracket gearshift comprises the auxiliary drive, and a power flow from the auxiliary drive and a power flow from the bottom bracket shaft are combined at the input stage or at an output stage.
2 . The bottom bracket gearshift according to claim 1 , wherein the second input gear on the drive side of the input stage is seated on a hollow shaft on the drive side of the input stage, and the hollow shaft is mounted on the bottom bracket shaft.
3 . The bottom bracket gearshift according to either claim 1 or 2 , wherein a freewheel is arranged between the input stage and the bottom bracket shaft.
4 . The bottom bracket gearshift according to claim 2 , wherein the bottom bracket gearshift comprises an output-side hollow shaft, to which a drive gear for a traction device extending to a rear wheel of the electric bicycle is attachable, and wherein the bottom bracket shaft extends coaxially in the output-side hollow shaft.
5 . The bottom bracket gearshift according to claim 4 , wherein at a transmission output of the shift gearbox an output stage comprises a driven-side output gear coaxial with the bottom bracket shaft and an output gear on the drive side on an output shaft of the shift gearbox.
6 . The bottom bracket gearshift according to claim 5 , wherein the driven-side output gear drives the output-side hollow shaft.
7 . The bottom bracket gearshift according to claim 6 , wherein the hollow shaft on the drive side and the output-side hollow shaft are arranged side by side on the bottom bracket shaft.
8 . The bottom bracket gearshift according to claim 6 , comprising a housing that accommodates the shift gearbox and the bottom bracket shaft and that is configured to accommodate the auxiliary drive.
9 . The bottom bracket gearshift according to claim 5 , wherein the output stage is configured as a reduction gear.
10 . The bottom bracket gearshift according to claim 9 , wherein the hollow shaft on the drive side and the output-side hollow shaft are arranged side by side on the bottom bracket shaft.
11 . The bottom bracket gearshift according to claim 5 , wherein the auxiliary drive is structurally integrated into the bottom bracket gearshift.
12 . The bottom bracket gearshift according to claim 4 , wherein the hollow shaft on the drive side and the output-side hollow shaft are arranged side by side on the bottom bracket shaft.
13 . The bottom bracket gearshift according to claim 1 , comprising a housing that accommodates the shift gearbox and the bottom bracket shaft and that is configured to accommodate the auxiliary drive.
14 . An electric bicycle with the bottom bracket gearshift according to claim 1 , the bottom bracket gearshift being provided in an area of a bottom bracket of the electric bicycle.
15 . The bottom bracket gearshift according to claim 1 , wherein the bottom bracket gearshift comprises an output-side hollow shaft, to which a drive gear for a traction device extending to a rear wheel of the electric bicycle is attachable, and wherein the bottom bracket shaft extends coaxially in the output-side hollow shaft.
16 . A bottom bracket gearshift for an electric bicycle with an auxiliary drive, comprising:
a bottom bracket shaft, a shift gearbox configured for setting different transmission ratios, and an input stage arranged at a transmission input of the shift gearbox; and
a housing that accommodates the shift gearbox and the bottom bracket shaft and that is configured to accommodate the auxiliary drive,
wherein the input stage is arranged between the shift gearbox and the bottom bracket shaft and is configured as a speed increasing gear for increasing the rotational speed of the bottom bracket shaft, and wherein the shift gearbox has two or more shift stages which are provided with shifting clutches for shifting different gears of the shift gearbox.
17 . The bottom bracket gearshift according to claim 16 , wherein at a transmission output of the shift gearbox an output stage comprises a driven-side output gear coaxial with the bottom bracket shaft and an output gear on a drive side on an output shaft of the shift gearbox.
18 . A bottom bracket gearshift for an electric bicycle with an auxiliary drive, comprising:
a bottom bracket shaft, a shift gearbox configured for setting different transmission ratios, and an input stage arranged at a transmission input of the shift gearbox,
wherein the input stage is arranged between the shift gearbox and the bottom bracket shaft and is configured as a speed increasing gear for increasing the rotational speed of the bottom bracket shaft, and wherein the shift gearbox has two or more shift stages which are provided with shifting clutches for shifting different gears of the shift gearbox, and
wherein at a transmission output of the shift gearbox an output stage comprises a driven-side output gear coaxial with the bottom bracket shaft and an output gear on a drive side on an output shaft of the shift gearbox.
19 . The bottom bracket gearshift according to claim 18 , wherein the input stage comprises a first input gear on a driven side of the input stage on an input shaft of the shift gearbox and a second input gear on a drive side of the input stage coaxial with the bottom bracket shaft.