Power unit and method

Patent metadata

Field	Value
Publication number	US-11932349-B2
Application number	US-202017622296-A
Country	US
Kind code	B2
Filing date	Jun 26, 2020
Priority date	Jun 28, 2019
Publication date	Mar 19, 2024
Grant date	Mar 19, 2024

Abstract

A power unit for a pedal vehicle includes a pedal shaft, an output shaft arranged to transfer torque to a vehicle wheel, a main epicyclic gear set arranged to control transmission ratio between the pedal shaft and the output shaft, an assist motor connected to an assist gear of the main epicyclic gear set, and a control motor connected to a control gear of the main epicyclic gear set. The control motor and the control gear form a control assembly of the power unit. The power unit includes a one-way clutch provided to the control assembly of the power unit and arranged to transmit rotation in only a first rotation direction.

First claim

The invention claimed is:

1. A power unit having a housing for a pedal vehicle, the power unit comprising:
a main epicyclic gear set arranged to control transmission ratio between a pedal shaft and an output shaft of the pedal vehicle, the main epicyclic gear set comprises a sun gear, a ring gear, plurality of planet gears between the sun gear and the ring gear and a planet carrier connected to the planet gears;
an assist motor connected to an assist gear of the main epicyclic gear set and arranged to transmit torque to the output shaft;
a control motor connected to a control gear of the main epicyclic gear set and arranged to adjust the transmission ratio of the main epicyclic gear set, the control motor and the control gear forming a control assembly of the power unit; and
a one-way clutch provided to the control assembly of the power unit and arranged to transmit rotation in only a first rotation direction,
the pedal shaft is connected to the planet carrier, the ring gear is connected to the output shaft, the control motor is connected to the sun gear, and the assist motor is connected to the ring gear;
the ring gear forming the assist gear;
the sun gear forming the control gear; and
the control motor and the sun gear forming the control assembly and the one-way clutch is provided to the control assembly,
wherein:
the one-way clutch is arranged between the sun gear and the housing of the power unit.

2. The power unit according to claim 1 , wherein the one-way clutch comprises a first operating state in which the one-way clutch is arranged to transmit rotation in the first rotation direction of the control gear, and a second operating state in which the one-way clutch is prevented from transmitting rotation in a second rotation direction of the control gear.

3. The power unit according to claim 2 , wherein:
the one-way clutch is provided in connection with the control gear, in the first operating state of the one-way clutch the control gear is arranged to rotate in the first rotating direction and in the second operating state of the one-way clutch rotation of the control gear in the second rotation direction is prevented.

4. The power unit according to claim 2 , wherein the one-way clutch comprises:
a freewheel arranged to enable rotation in the first rotation direction and prevent rotation in the second rotation direction; or
a one-way gear mechanism arranged to enable rotation in the first rotation direction and prevent rotation in the second rotation direction.

5. The power unit according to claim 2 , wherein the one-way clutch comprises:
a wedge lock mechanism having the first operating state in which the wedge lock mechanism is in a disengaged position and arranged to transmit rotation in the first rotation direction, and the second operating state in which the wedge lock mechanism is in an engaged position and arranged to prevent transmitting rotation in the second rotation direction; or
a friction lock mechanism having the first operating state in which the friction lock mechanism is in a disengaged position and arranged to transmit rotation in the first rotation direction, and the second operating state in which the friction lock mechanism is in an engaged position and arranged to prevent transmitting rotation in the second rotation direction; or
a band lock mechanism having the first operating state in which the band lock mechanism is in a disengaged position and arranged to transmit rotation in the first rotation direction, and the second operating state in which the band lock mechanism is in an engaged position and arranged to prevent transmitting rotation in the second rotation direction; or
a synchro mechanism having the first operating state in which the synchro mechanism is in a disengaged position and arranged to transmit rotation in the first rotation direction, and the second operating state in which the synchro mechanism is in an engaged position and arranged to prevent transmitting rotation in the second rotation.

6. The power unit according to claim 1 , wherein the power unit comprises the housing accommodating the main epicyclic gear set, the control motor and the assist motor, the housing comprising a hub arranged around the pedal shaft and an arm extending from the hub, and that the control motor is arranged in the hub and the assist motor is arranged in the arm.

7. The power unit according to claim 1 , wherein:
the power unit comprises at least one reduction gear set between control motor and the main epicyclic gear set; or
at least one reduction gear set between assist motor and the main epicyclic gear set; or
the power unit comprises at least one reduction gear set between control motor and the main epicyclic gear set, and at least one reduction gear set between assist motor and the main epicyclic gear set.

8. A method for operating a power unit of a pedal vehicle having a pedal shaft and an output shaft for transferring torque to a vehicle wheel, the power unit having a housing, the method comprising:
controlling transmission ratio between the pedal shaft and the output shaft with a main epicyclic gear set comprising a sun gear, a ring gear, a plurality of planet gears between the sun gear and the ring gear and a planet carrier connected to the planet gears;
transmitting power to an assist gear of the main epicyclic gear set with an assist motor for transmitting power to the output shaft of the pedal vehicle;
adjusting the transmission ratio of the main epicyclic gear set with a control motor by transmitting power to a control gear of the epicyclic gear set, the control motor and the control gear forming a control assembly of the power unit;
operating the power unit in a first operating mode in which the control gear rotates in a first rotation direction, in which first operating mode the control motor is operable adjusting the transmission ratio of the main epicyclic gear set by transmitting power to the control gear; and
operating the power unit in a second operating mode in which torque transmission between the of the control gear and the control motor is disabled,

wherein the method comprises:
transmitting power to the ring gear of the main epicyclic gear set with the assist motor for transmitting power to the output shaft of the pedal vehicle;
adjusting the transmission ratio of the main epicyclic gear set with the control motor by transmitting power to the sun gear of the epicyclic gear set, the control motor and the sun gear forming the control assembly of the power unit;
operating the power unit in the first operating mode in which the sun gear rotates in the first rotation direction, in which first operating mode the control motor is operable adjusting the transmission ratio of the main epicyclic gear set by transmitting power to the sun gear; and
operating the power unit in the second operating mode in which torque transmission between the sun gear and the control motor is disabled with a one-way clutch provided between the sun gear and the housing of the power unit.

9. The method according to claim 8 , wherein in the second operating mode:
rotation of the sun gear of the main epicyclic gear set is prevented.

10. The method according to claim 8 , wherein:
in the second operating mode adjusting the transmission ratio of the main epicyclic gear set is disabled with a one-way clutch or free-wheel.

11. The method according to claim 10 , wherein the main epicyclic gear set is arranged to control the transmission ratio between the pedal shaft and the output shaft of the pedal vehicle.

Assignees

• Gates Corp

Inventors

• Peltola Iiro

Classifications

• B62M6/45 Primary

  Control or actuating devices therefor · CPC title

• B62M6/55 Primary

  power-driven at crank shafts parts · CPC title

• B62M11/145 Primary

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

• F16D28/00

  Electrically-actuated clutches (arrangements for synchronisation F16D23/02; clutches actuated directly by means of an electromagnet F16D27/00; automatic clutches F16D43/00 - F16D45/00; external control F16D48/00) · CPC title

• F16D41/24

  specially adapted for cycles · CPC title