Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
  • B62M—RIDER PROPULSION OF WHEELED VEHICLES OR SLEDGES; POWERED PROPULSION OF SLEDGES OR SINGLE-TRACK CYCLES; TRANSMISSIONS SPECIALLY ADAPTED FOR SUCH VEHICLES
  • B62M6/00—Rider propulsion of wheeled vehicles with additional source of power, e.g. combustion engine or electric motor
  • B62M6/40—Rider propelled cycles with auxiliary electric motor
  • B62M6/55—Rider propelled cycles with auxiliary electric motor power-driven at crank shafts parts
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
  • B62K—CYCLES; CYCLE FRAMES; CYCLE STEERING DEVICES; RIDER-OPERATED TERMINAL CONTROLS SPECIALLY ADAPTED FOR CYCLES; CYCLE AXLE SUSPENSIONS; CYCLE SIDE-CARS, FORECARS, OR THE LIKE
  • B62K5/00—Cycles with handlebars, equipped with three or more main road wheels
  • B62K5/02—Tricycles
  • B62K5/027—Motorcycles with three wheels
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
  • B62M—RIDER PROPULSION OF WHEELED VEHICLES OR SLEDGES; POWERED PROPULSION OF SLEDGES OR SINGLE-TRACK CYCLES; TRANSMISSIONS SPECIALLY ADAPTED FOR SUCH VEHICLES
  • B62M17/00—Transmissions characterised by use of rotary shaft, e.g. cardan shaft
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
  • B62M—RIDER PROPULSION OF WHEELED VEHICLES OR SLEDGES; POWERED PROPULSION OF SLEDGES OR SINGLE-TRACK CYCLES; TRANSMISSIONS SPECIALLY ADAPTED FOR SUCH VEHICLES
  • B62M6/00—Rider propulsion of wheeled vehicles with additional source of power, e.g. combustion engine or electric motor
  • B62M6/40—Rider propelled cycles with auxiliary electric motor
  • B62M6/45—Control or actuating devices therefor
  • B62M6/50—Control or actuating devices therefor characterised by detectors or sensors, or arrangement thereof
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
  • B62M—RIDER PROPULSION OF WHEELED VEHICLES OR SLEDGES; POWERED PROPULSION OF SLEDGES OR SINGLE-TRACK CYCLES; TRANSMISSIONS SPECIALLY ADAPTED FOR SUCH VEHICLES
  • B62M6/00—Rider propulsion of wheeled vehicles with additional source of power, e.g. combustion engine or electric motor
  • B62M6/40—Rider propelled cycles with auxiliary electric motor
  • B62M6/60—Rider propelled cycles with auxiliary electric motor power-driven at axle parts
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
  • B62M—RIDER PROPULSION OF WHEELED VEHICLES OR SLEDGES; POWERED PROPULSION OF SLEDGES OR SINGLE-TRACK CYCLES; TRANSMISSIONS SPECIALLY ADAPTED FOR SUCH VEHICLES
  • B62M6/00—Rider propulsion of wheeled vehicles with additional source of power, e.g. combustion engine or electric motor
  • B62M6/40—Rider propelled cycles with auxiliary electric motor
  • B62M6/60—Rider propelled cycles with auxiliary electric motor power-driven at axle parts
  • B62M6/65—Rider propelled cycles with auxiliary electric motor power-driven at axle parts with axle and driving shaft arranged coaxially
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
  • B62M—RIDER PROPULSION OF WHEELED VEHICLES OR SLEDGES; POWERED PROPULSION OF SLEDGES OR SINGLE-TRACK CYCLES; TRANSMISSIONS SPECIALLY ADAPTED FOR SUCH VEHICLES
  • B62M6/00—Rider propulsion of wheeled vehicles with additional source of power, e.g. combustion engine or electric motor
  • B62M6/40—Rider propelled cycles with auxiliary electric motor
  • B62M6/70—Rider propelled cycles with auxiliary electric motor power-driven at single endless flexible member, e.g. chain, between cycle crankshaft and wheel axle, the motor engaging the endless flexible member

Definitions

• This application relates to human powered vehicles.
• it relates to a drivetrain for a human powered, electrically assisted vehicle.
• Motorized pedal power vehicles consist of an attached motor and a transmission that is used to either power the vehicle unassisted, or to assist with pedaling.
• An example of a motorized pedal power vehicle is a motorized bicycle.
• Different types of motors and power sources can power motorized pedal power vehicles.
• Common power sources include internal combustion engines fuelled by gasoline and/or diesel, steam engines, air engines, as well as electric motors. These power sources may be directly connected to an output shaft or geared to adjust the output speed and torque.
• Power can be applied to a drive wheel using different methods: (1 ) The front or rear wheel may be powered directly by a power source built into the hub, wheel or rim. (2) A power source mounted within the vehicle's frame may drive the rear wheel via a mechanical power transmission system such as via "chain drives” (i.e. a sprocket with a chain), “belt drives” (e.g. a rubber belt), or “shaft drives” (i.e. directly coupled with a rigid shaft). (3) Power may be transferred to a wheel from a motor mounted directly above, by bringing a powered roller or rubber belt into contact with the wheel or tire.
• chain drives i.e. a sprocket with a chain
• belt drives e
• motorized pedal power vehicles are marketed either as complete designs or as add-on motor kits for use on unpowered vehicles. Lighter and more powerful batteries enable electric motors to be more commonly used in motorized pedal power vehicles. As well, such technologies have proven useful for people with physical disabilities and/or restricted mobility such as arthritis and knee injuries.
• US Patent No. 3,921 ,467 to Matsuura describes a bicycle with a drive train located in the center of the cycle body that consists of a primary sprocket and final sprocket with a tensioner sprocket in between. Adding a secondary sprocket between the primary and final sprockets can modify the gear ratios of the drive train.
• US Patent No. 6,352, 131 to Lin describes a unidirectional rotating assembly that allows a chain-ring to rotate while the crank and axle remains still. This design enables the bike to be propelled while the crank is stationary and allows the users to still be able to shift gears.
• US Patent No. 7,314, 109 to Holland describes an electrically powered bicycle that includes a hub motor that is mounted to the bicycle frame by its axle. When the bicycle is coasting, the design will enable the rear wheel to drive the motor to provide downhill, regenerative braking capability.
• US Patent No. 7,461 ,714 to Holland also describes a frame-mounted motor that is connected to pedals and to a rear driven wheel through an intermediate jackshaft. A freewheel within this design can recharge batteries during braking or while coasting downhill.
• US Patent Application Pub. No. 2010/0307851 to Lin further describes a power-assist system for a bicycle comprising of three components: a motor, a speed- reduction section, and a power-assist section.
• Such systems operate in four modes: (1 ) power-assist pedaling mode; (2) pedal only mode; (3) power-assist only mode; and (4) coasting no-power mode.
• the present invention is directed to a drivetrain for a human powered, electrically assisted vehicle, such as a tricycle.
• the drivetrain which includes two electrical motors, reduces the effort that a person needs to exert to move a vehicle, increases the acceleration and efficiency of the vehicle, recovers electrical energy when the vehicle is braking, and powers the vehicle to move in reverse. It accomplishes these solutions while accommodating freewheel mechanisms that allow the crank to remain stationary while the vehicle moves forward.
• the use of two motors in the drivetrain allows them to be operated within their higher efficiency performance zones, allowing for greater overall efficiency of the motors when converting stored electrical energy to kinetic energy in order to drive the vehicle.
• This arrangement allows for greater torque to be applied to the rear wheel, while staying within restrictive power limits compared with other methods, such as installing a single hub motor on the rear wheel or a single mid-mount motor that drives the rear wheel.
• a drivetrain system for a human-powered vehicle comprising: a crank configured to be rotated by a human; a shaft driven by the crank; a drive wheel configured to be driven by the shaft; a first motor configured to power the shaft; a first freewheel mechanism connected between the crank and the shaft such that the first motor powers the shaft to drive the drive wheel forwards without back-driving the crank; and a second motor configured to power the drive wheel or a further drive wheel.
• the drivetrain system may also include a second freewheel mechanism connected between the shaft and the drive wheel such that the drive wheel moves forwards without back-driving the first motor or the crank.
• the drivetrain system may also comprise a transmission connected between one of: the first motor and the second freewheel mechanism; the second freewheel mechanism and the drive wheel; and the first freewheel mechanism and the first motor.
• a three-wheeled vehicle installed with a drivetrain system
• the drivetrain system comprising: a crank configured to be rotated by a human; a shaft driven by the crank; a drive wheel of a three-wheeled vehicle configured to be driven by the shaft; a first motor configured to power the shaft; a first freewheel mechanism connected between the crank and the shaft such that the first motor powers the shaft to drive the drive wheel of the three-wheeled vehicle forwards without back- driving the crank; and a second motor configured to power the drive wheel or a further drive wheel of the three-wheeled vehicle.
• the vehicle may also include a second freewheel mechanism connected between the shaft and the drive wheel such that the drive wheel of the three-wheeled vehicle moves forwards without back-driving the first motor or the crank.
• a method for powering a human-powered vehicle comprising: driving a shaft with a first motor; driving a crank by a human, the crank driving the shaft via a first freewheel mechanism such that the first motor drives the shaft without back-driving the crank; driving a drive wheel by a second motor; and driving at least one of the drive wheel and a further drive wheel by the shaft, the shaft driving the at least one of the drive wheel and further drive wheel via a second freewheel mechanism such that the at least one of the drive wheel and further drive wheel moves forwards without back-driving the first motor or the crank.
• FIG. 1 is a schematic diagram of a basic drivetrain system according to the invention.
• FIG. 2 is a top view of a first exemplary embodiment of the drivetrain system.
• FIG. 3 is a side view of the first exemplary embodiment of the drivetrain system.
• FIG. 4 is a perspective view of the first exemplary embodiment of the drivetrain system.
• FIG. 5 is a top view of a second exemplary embodiment of the drivetrain system.
• FIG. 6 is a side view of the second exemplary embodiment of the drivetrain system.
• FIG. 7 is a perspective view of the second exemplary embodiment of the drivetrain system.
• FIG. 8 is a top view of a third exemplary embodiment of the drivetrain system.
• FIG. 9 is a side view of the third exemplary embodiment of the drivetrain system.
• FIG. 10 is a perspective view of the third exemplary embodiment of the drivetrain system.
• FIG. 1 1 is a schematic representation of an exemplary embodiment of a control system for the drivetrain systems, including its connected input and output modules.
• Cadence The rate at which a cyclist or other driver of a human-powered vehicle turns the pedals. Cadence is measured, for example, in revolutions per minute. The cadence should be suitable for the cyclist, because, for example, spinning a crank too fast can be uncomfortable.
• back-Driving refers to operating the primary driving mechanism as if it were powering the driven wheel.
• a bicycle with no freewheel mechanism that is moving downhill under the influence of gravity alone has a back-driven crank because it will be rotating, even though the cyclist will not be powering it.
• Gear Motor This is a motor with gears incorporated in order to reduce the output shaft speed and increase the output shaft torque.
• FIG. 1 a simplified diagram of a basic drivetrain system for a human-powered vehicle is shown, being incorporated in each of the three exemplary embodiments of drivetrain systems 10, 100 and 200 described in detail later in reference to FIGS. 2-4, 5-7 and 8-10, respectively.
• a crank 1 which is configured to be powered by a human, for example using pedals attached to it.
• the crank 1 drives, via a first freewheel mechanism 2, a shaft 3.
• the first freewheel mechanism 2 allows the shaft 3 to rotate in the forward direction without the crank being back-driven.
• the shaft 3 is also driven by a first motor 4, and may be powered completely by the first motor, partially by the first motor, or not at all by the first motor.
• Shaft 3 in turn drives, via an optional second freewheel mechanism 5, the drive wheel 6.
• the second freewheel mechanism 5 allows the drive wheel 6 to rotate in the forward direction without the first motor 4 or the crank 1 being back-driven.
• the drive wheel 6 is also driven by a second motor 7.
• the drive wheel 6 may be powered completely by the second motor 7, partially by the second motor, or not at all by the second motor.
• the drive wheel 6 may be driven in reverse by the second motor 7. Drive power transmitted between the pedals, crank 1 , shaft 3, motors
• An optional system control 8 generally representing a control system 300 described in detail later in reference to FIG. 1 1 , is connected to the motors 4, 7 and the crank 1 .
• the system control 8 takes inputs from one or more sensors on the crank 1 and motors 4, 7 and provides control signals to the motors.
• the control signals optimize the amount of power used to drive the motors.
• a transmission 9 may be included in the powertrain system, and may also be connected to the system control 8. If a transmission is included in the drivetrain system, then the second freewheel mechanism 5 will be required if the transmission cannot be back-driven. The transmission should therefore be installed in the drivetrain system upstream of the second freewheel mechanism.
• crank 1 and first motor 4 may drive the drive wheel 6, and the second motor 7 may drive a further drive wheel in the same vehicle as the first drive wheel 6.
• This may be the case for a tricycle, for example, in which the two rear wheels are powered by different portions of the drivetrain system.
• all of the crank 1 , first motor 4 and second motor 7 may be configured to power a single drive wheel.
• crank 1 1 which is fitted with pedals, is powered by a driver of a vehicle in which the drivetrain system 10 is installed.
• a belt or chain 12 tensioned by an idler wheel 14, connects the crank 1 1 to a wheel 16 that is mounted on an intermediate shaft 20.
• the intermediate shaft 20 is connected to a wheel 22, which in turn is connected by a belt or chain 24 to a first freewheel 26 on first motor shaft 30.
• Wheels 16, 22 may be of different sizes in order to provide suitable gearing.
• the mechanism of the first freewheel 26 allows the vehicle to move forward without the need to back-drive the crank 1 1 .
• first electric motor 32 Connected to motor shaft 30 is a first electric motor 32 and further wheel 34.
• the first electric motor 32 which may be a gear motor, may be powered to drive the first motor shaft 30 and wheel 34 in the forward direction (i.e. forward direction of the vehicle), either entirely or by adding power to the power that is provided by the driver turning the crank 1 . If no electrical power is supplied to the first motor 32, it will still rotate as the crank is rotated.
• Wheel 34 on first motor shaft 30 is connected by a belt or chain 36 to a wheel 38 that is mounted on a transmission input shaft 40.
• Transmission 42 is connected to and takes its drive input from input shaft 40. As the transmission shaft 40 is rotated, the transmission transfers power to wheel 44 mounted on the transmission output shaft 45.
• the transmission 42 is, for example, a variable gear ratio transmission, such as a continuously variable automatic transmission.
• Wheel 44 is connected via belt or chain 46 to a second freewheel 48 mounted on the axle 50 of drive wheel 52.
• the optional mechanism of freewheel 48 allows the drive wheel 52 to rotate forwards without back-driving the first motor 32 or the crank 1 . In some cases, the freewheel 48 is necessary because the transmission may not be able to be back-driven.
• a second motor 54 which may also be a gear motor, is connected directly to the drive wheel 52.
• the second motor 54 can be used to add power to the drive wheel 52 in either forward or reverse directions, and can also be used to recover energy by reducing vehicle speed, otherwise known as regenerative braking.
• Second motor 54 may be a hub motor or a wheel motor, and drives the drive wheel 52 directly.
• the second motor 54 is connected to the drive wheel 52 without a freewheel mechanism so that it can drive the drive wheel in both forward and reverse directions.
• Much of the drivetrain system 100 is similar to that of the first embodiment 10, such as the crank 1 10 and first motor 132, which are used with the same arrangement of connecting shafts, belts, chains and/or wheels to provide human and electrical power respectively to the drive wheel 152 mounted on axle 150.
• One difference in drivetrain system 100 is that the second motor 154 is located off-axis from the axle 150 of the drive wheel 152.
• Second motor 154 drives wheel 160 that is connected via belt or chain 162 to wheel 164 mounted on the axle 150 of the drive wheel 152.
• FIGS. 8-10 A third exemplary embodiment of the drivetrain system, generally designated 200, is shown in FIGS. 8-10.
• a driver pedal s to turn the crank 210, which is connected to a shaft 212 which rotates when the crank is turned.
• the shaft 212 is connected to a freewheel mechanism 214, which allows the vehicle to move forwards without the crank 210 being back-driven.
• the freewheel mechanism 214 is in turn connected to shaft 216, which is connected via a universal joint 230 to first motor 232.
• the first motor 232 is in turn connected, via another optional freewheel mechanism 240 to the transmission 242. If desired, the freewheel mechanism 240 allows the drive wheel 252 to rotate forwards without back-driving the first motor 232 or the crank 210.
• the transmission 242 drives the transmission output shaft 244, which in turn rotates the drive wheel 252 mounted on axle 250.
• a second motor 254 of the drivetrain system 200 is connected to the drive wheel 252 to directly drive the drive wheel 252 in either a forward or reverse direction, and for regenerative braking.
• the second motor 254 may be located off-axis from the axle 250 of the drive wheel 252, as in the preceding drivetrain system 100 of FIGS 5-7.
• power to the drive wheel 252 may be supplied from the off-axis second motor 254 via a belt, chain or shaft.
• control system 300 includes a system controller 305 for controlling first and second motors 340, 342 and the transmission 360 of the control system 300.
• the system controller 305 controls these components in order to maximize vehicle performance under various driving conditions. For example, if the vehicle goes up a hill, the gear ratio will change to allow for higher torque to be applied to the drive wheel. Vice versa, at high vehicle speeds the gear ratio will change up to allow for lower user cadence at higher drive wheel speeds.
• the system controller 305 receives inputs from the pedal module 310, which in turn receives its inputs from one or more sensors connected to the pedals and/or crank.
• sensors may be a cadence sensor 312 and a torque sensor 314.
• the system controller 305 also receives inputs from the motor controller 320, and also provides outputs to it.
• the motor controller 320 receives inputs from various sensors attached to the aforementioned components of the drivetrain systems 10, 100 and 200, such as a speed sensor 322 for the first motor 340, a speed sensor 324 for the second motor 342, a current sensor 326 for the first motor 340 and a current sensor 328 for the second motor 342. Based upon the inputs received from the sensors 322-328 and the input received from the system controller 305, the motor controller 320 sends control signals to the first motor 340 and the second motor 342 in order to control the electrical power applied to them.
• an optimizer module 370 in the system controller 305 calculates the optimum power split between the two motors 340, 342.
• the optimizer module 370 may be located in the motor controller 320. The split is calculated so that, as far as possible, both motors 340, 342 are being driven in their optimum efficiency ranges while still achieving vehicle torque and power output as the user is expecting. If this is not possible, the motors are driven so that their combined efficiency is optimal.
• the system controller 305 also receives inputs from the transmission 360, which in turn receives inputs from a sensor 362 on its input shaft and a sensor 364 on its output shaft.
• the transmission module 360 as a result of receiving signals from the sensors 362, 364 and from the system controller 305, sends output control signals to the gear ratio control module 366 in the transmission.
• the control system 300 requires the driver to pedal backwards in order to initiate reverse power from the motors, so that the driver must pedal faster than the crank would normally rotate. This makes it so that the driver does not feel like the crank is being back-driven when the vehicle moves in reverse.
• the crank rotates in reverse. This may occur, for example, when the vehicle is rolling backwards downhill.
• the system controller 305 and its connected modules may be embodied in software, firmware and/or hardware.
• crank and two motors power a single drive wheel
• all of these embodiments may be split into the two portions of a drivetrain system, in which the crank and first motor power one drive wheel and the second motor powers another drive wheel.
• the first motor 32 could be attached to the intermediate shaft 20 by a belt, chain, shaft or gear, rather than in-line.
• Freewheel mechanisms can be located in positions other than those depicted in the embodiments described herein.
• a freewheel mechanism instead of a freewheel mechanism being located in freewheel 48 on the axle 50, it may instead be located at wheel 44.
• the electric motors may be located in different positions to those that have been shown.
• the first motor may be located between the transmission and drive wheel.
• the first motor may be located between the crank and the intermediate shaft.
• the first motor may directly power the crank (i.e. the shaft of the crank) or directly power the intermediate shaft.
• the drivetrain may also be used with motors other than electrical motors.
• the second motor may be used to drive a second drive wheel.
• the drivetrain would be configured to drive a first drive wheel using the crank and the first motor and the second drive wheel using the second motor.
• the drivetrain system may also conceivably be split in a bicycle, for example, in which the crank and the first motor power the rear wheel and the second motor powers the front wheel.

Landscapes

• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• Transportation (AREA)
• Automatic Cycles, And Cycles In General (AREA)
• Electric Propulsion And Braking For Vehicles (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Publications (1)

Family

ID=56125510

Family Applications (1)

Country Status (6)

Cited By (2)

Families Citing this family (8)

Citations (6)

Family Cites Families (13)

• 2014
  • 2014-12-17 US US14/574,121 patent/US9469373B2/en not_active Expired - Fee Related
• 2015
  • 2015-12-14 EP EP15868770.7A patent/EP3233618B1/en active Active
  • 2015-12-14 CA CA2970262A patent/CA2970262A1/en not_active Abandoned
  • 2015-12-14 WO PCT/CA2015/051317 patent/WO2016095028A1/en not_active Ceased
  • 2015-12-14 JP JP2017531378A patent/JP6694885B2/ja not_active Expired - Fee Related
  • 2015-12-14 CN CN201580076283.0A patent/CN107249975B/zh not_active Expired - Fee Related

Patent Citations (6)

Also Published As

Similar Documents

Legal Events