DEVICE FOR ENERGY RECOVERY IN BICYCLES WITH A MID-MOUNTED MOTOR DRIVE UNIT AND METHOD FOR OPERATING THE SAME

Abstract

The invention relates to a device for energy recovery in bicycles with a mid-mounted motor drive unit and at least one rear wheel, comprising a first component that is connected to an element of the rear wheel hub or the rear wheel, such that a rotation of the rear wheel is transmitted to the first component, regardless of the direction of rotation, an energy-transmission device interacting with the first component, a recuperation element that interacts with the energy-transmission device, and a generator that interacts with the recuperation element to recover the rotational energy of the rotational movement of the rear wheel.

Claims

1. A device (1) for energy recovery in bicycles (2) with a mid-mounted motor drive unit (3) and at least one rear wheel (4), comprising: a first component (10) that is connected to an element of a rear wheel hub (4), or of the rear wheel (18), such that a rotation of the rear wheel (18) is transmitted to the first component (10), regardless of the direction of rotation; an energy-transmission device (11), interacting with the first component (10), a recuperation element (12) that interacts with the energy-transmission device (11), and a generator (13) that interacts with the recuperation element (12) to recover the rotational energy of the rotational movement of the rear wheel.

2. A device according to claim 1, characterized in that the energy-transmission device (11) has at least one mechanical transmission element and/or at least one hydraulic transmission element.

3. A device according to claim 2, characterized in that the energy-transmission device (11) comprises a traction mechanism drive, in particular a timing belt, a chain and/or a cardan shaft.

4. A device according to claim 1, characterized in that the recuperation element (12) comprises a shaft.

5. A device according to claim 1, characterized in that the recuperation element (12) is located in the region between bottom bracket (5) and rear wheel hub (4) or in the vertical direction above the bottom bracket (5).

6. A device according to claim 1, characterized in that the recuperation element (12) is at least partially located outside the housing (7) of the mid-mounted motor drive unit (3) or completely inside the housing (7).

7. A device according to claim 1, characterized in that an adaptation device (14) is arranged for the energy-transmission device (11), which is configured to at least partially compensate a deterioration of the energy transfer of the energy-transmission device (11).

8. A device according to claim 1, characterized in that the recuperation element (12) is configured as part of the generator, in particular in the form of a generator shaft for a surrounding stator of the generator.

9. A device according to claim 1, characterized in that the recuperation element (12) is configured as a transmission drive shaft having at least one clutch.

10. A device according to claim 1, characterized in that the energy-transmission device (11) is located above a drive transmission device (6) of the mid-mounted motor drive unit (3) that drives the rear wheel.

11. A device according to claim 1, characterized in that the energy-transmission device (11) is at least partially arranged in a protective housing (17).

12. A device according to claim 1, characterized in that the energy-transmission device (11) and/or the recuperation element (12) and/or the first component (10), on the one hand, and a transmission device (9) of the mid-mounted motor drive unit (3) for driving the rear wheel, on the other hand, are arranged in essentially spatially separated regions on the bicycle (2), in particular on different sides of the bicycle (2).

13. A device according to claim 1, characterized in that the first component (10) is permanently connected to the rear wheel hub (4) or detachably connected to the rear wheel.

14. A device according to claim 13, characterized in that the first component engages into the spokes of the rear wheel for rotation.

15. A device according to claim 14, characterized in that the first component comprises at least one pin, in particular a plurality of pins for engaging with the spokes.

16. A method for operating a device according to claim 1, characterized in that energy recovery by means of the device is carried out depending on the operation of the bicycle (2).

17. A method according to claim 16, characterized in that sensor data, used for detecting the driving operation of the bicycle (2), is evaluated by a control device (15) and that energy is recovered based on the detected driving operation.

18. A method according to claim 16, characterized in that the energy recovery is carried out continuously and/or in steps, depending on the operation of the bicycle (2).

19. A method according to claim 16, characterized in that the energy recovery can be activated manually.

20. A bicycle with a device according to claim 1.

Description

[0036] It is shown, schematically, in

[0037] FIG. 1 a device according to an embodiment of the present invention in a top view;

[0038] FIG. 2 a device according to an embodiment of the present invention in a side view;

[0039] FIG. 3 a device according to an embodiment of the present invention in a side view:

[0040] FIG. 4 a device according to an embodiment of the present invention in a side view; and

[0041] FIG. 5 a device according to an embodiment of the present invention.

[0042] FIG. 1 shows a device according to an embodiment of the present invention in a top view.

[0043] In detail, FIG. 1 shows a device 1 for recovering energy for a two-wheeler. The two-wheeler has a mid-mounted motor drive unit 3, which has a bottom bracket bearing 5 with bottom bracket spindle 8 with a chainring 9. The chainring 9 is connected via a chain 6 to a sprocket 16, which is mounted on the rear hub 4 of the two-wheeler. By rotation of the chainring 9, the powered drive of the rear wheel of the two-wheeler can take place.

[0044] In addition, in FIG. 1 a recess is provided in the upper right part of the housing 7 of the mid-mounted motor drive unit 3, whereas the width of said recess being configured in such way that parallel to the connection between the chainring 9 and the sprocket 16 via the chain 6, a timing belt 11 can be placed. The latter is connected on the one hand to the mid-mounted motor drive unit 3 by the recuperation shaft 12, which projects partially out of the housing 7, and on the other hand to a toothed washer 10, which is fixed to the rear wheel hub 4 of the two-wheeler. The recuperation shaft 12 is hereby arranged “behind” the bottom bracket spindle 8 (thus outlined in FIG. 1 by being arranged on the right-hand side of the bottom bracket spindle) but can also be arranged above it and is mechanically independent of the bottom bracket spindle. The recuperation shaft 12 is hereby mounted in a way that provides the lowest possible resistance for rotational movements of the rear wheel.

[0045] In addition, a generator 13 for recuperation and a tensioning device 14 for the timing belt 11 are arranged in the mid-mounted motor drive unit 3. The tensioning device 14, for example in the form of a tension roller, serves to extend the service life of the timing belt 11. Likewise, the mid-mounted motor drive unit 3 comprises a control unit 15 for operating the recuperation. The control unit can also be placed at another position on the two-wheeler.

[0046] Altogether, the components of the two-wheeler, in particular the components toothed washer 10, timing belt 11 and recuperation shaft 12 shall have minimum energy consumption, which means that the overall power loss is as low as possible. For example, the contribution of device 1 to the total drive power loss is or is less than 1% in driving operation.

[0047] In other words, FIG. 1 shows a device 1 comprising a mechanically fixed connection to the rear wheel hub 4, in particular a small wheel in form of a toothed washer 10, which transmits, in particular by means of a timing belt 11, the rotational movement of the rear wheel, in particular in sliding mode, without freewheel and thus the energy involved in this movement of the rear wheel, to the recuperation shaft 12 of the mid-mounted motor drive unit 3, where the provided energy can be used for recuperation by the generator 13.

[0048] In other embodiments, not shown here, the recuperation shaft 12 acts as generator shaft with surrounding stator that is either permanently magnetic and/or has electromagnets, or the recuperation shaft 12 can also be configured as transmission axle with a clutch, configured to transmit the rotational energy in sliding mode to the mid-mounted motor drive unit 3 or its engine/electric motor respectively, which is in this configuration used as the generator for recuperation. With the latter embodiment, a separate generator 13 can then be dispensed with.

[0049] FIG. 2 shows a device according to an embodiment of the present invention in a side view.

[0050] In detail, FIG. 2 shows a device 1 according to FIG. 1. Here, the recuperation shaft 12 is arranged as in FIG. 1 behind the bottom bracket spindle 8, that is, between bottom bracket spindle 8 and rear wheel hub 4. As shown in FIG. 2, the timing belt 11 runs in parallel to the chain 6 and is arranged in FIG. 2 behind the chain 6—in viewing direction perpendicular to the drawing plane.

[0051] FIG. 3 shows a device according to an embodiment of the present invention in a side view.

[0052] In detail, FIG. 3 essentially shows a device 1 according to FIG. 1. In contrast to device 1 according to FIG. 1, the recuperation shaft 12 of device 1 is in FIG. 3 arranged vertically above the bottom bracket spindle 8, i.e. on same horizontal “height” as the bottom bracket spindle 8. As shown in FIG. 3, the timing belt 11 runs with an angle to the chain 6 and is arranged above the chain 6.

[0053] FIG. 4 shows a device according to an embodiment of the present invention in a side view.

[0054] In detail, FIG. 4 essentially shows a device 1 according to FIG. 3. In contrast to the device 1 shown in FIG. 3, in the device 1 according to FIG. 4, the recuperation shaft 12 and the timing belt 11 are protected by a housing 17, at least in the direction out of the drawing plane of FIG. 4.

[0055] The recuperation shaft 12 can be guided outwards on both sides of the mid-mounted motor drive unit 3 (thus perpendicular to the drawing plane). The recuperation shaft 12 can be guided outwards in a recess, as shown in FIG. 1, or as shown in FIG. 3 within in the housing 7 of the mid-mounted motor drive unit 3 in order to avoid a collision with the chainring 9 of the bottom bracket spindle. Depending on the positioning of the recuperation shaft 12 in the housing 3, the timing belt 11 runs around or above the chain stay of the frame. When the timing belt 11 runs above the chain stay, as shown in FIG. 3, a cover, for example in the form of a mudguard 17 can be arranged around it in order to protect both the timing belt 11 from dirt, as well as the human operator from the permanently rotating timing belt 11.

[0056] Whether the rotational energy available at the recuperation shaft 12 is used for recuperation depends in particular on the driving mode of the two-wheeler 2. The engine control unit 15 can start the recuperation automatically if due to various sensor data (speed of the bottom bracket spindle, angle of inclination of the ground, . . . ), a favorable driving mode (for example downhill) is recognized. In addition, it is conceivable that the recuperation will be switched on automatically when the brakes of the two-wheeler are actuated. As a result, the braking energy is used for recuperation and the brakes themselves are relieved.

[0057] The human driver may also be able to switch on the recuperation manually, if said driver intends to charge the energy storage, for example a battery, during the trip, for example in case of a slight downhill run, which cannot yet be considered as favorable for recuperation. By means of a step-by-step engagement, the usability and comfort of the function can be increased.

[0058] FIG. 5 shows a device according to an embodiment of the present invention.

[0059] In detail, FIG. 5 essentially shows a device 1 according to FIG. 3. In contrast to device 1 according to FIG. 3, at device 1 according to FIG. 5, the toothed washer 10, the timing belt 11 and the recuperation shaft 12 are arranged on the opposite side of sprocket 16, chain 6 and chainring 9 of the rear wheel 18 of the bicycle 2. In other words, recuperation, and drive of the same, are essentially carried out in spatially separated regions on the bicycle 2, in particular on different sides of the bicycle 2. A driving cogwheel respective a toothed washer 10 is mounted in particular on the rear wheel hub 4 and, in an embodiment, engages by one or more elements, for example trunnions, with elements of the rear wheel 18 for example spokes, so that the toothed washer 10 is driven according to the rotation of the rear wheel 18. In this outline, the toothed washer 10 can easily be removed from the rear wheel hub 4 whenever the rear wheel 18 is removed. In this respect, no structural modification of the rear wheel hub 4 may be required, and removal of the timing belt 11 is also not necessary upon removal of the rear wheel 18. Furthermore, a change in rotational speed, in particular an increase of the rotational speed of the recuperation shaft, can easily be provided by means of a corresponding gear ratio between the toothed washer 10 and the recuperation shaft 12. This improves the energy recovery in the drive unit 3 and makes it unnecessary to implement such amended elements within the mid-mounted motor drive 3.

[0060] In summary, at least one of the embodiments of the invention has at least one of the following advantages: [0061] Simple assembly or implementation. [0062] Cost-effective production and operation. [0063] Recuperation for two-wheelers with mid-mounted motor drive unit. [0064] Simple maintenance, especially if recuperation and drive are located on different sides and/or in different areas.

[0065] Although the present invention has been described on the basis of preferred embodiments, it is not limited to this, but can be modified in a variety of ways.

LIST OF REFERENCE SIGNS

[0066] 1 Device for energy recovery [0067] 2 Bicycle [0068] 3 Mid-mounted motor drive unit [0069] 4 Rear wheel hub [0070] 5 Bottom bracket [0071] 6 Chain [0072] 7 Housing [0073] 8 Bottom bracket spindle [0074] 9 Chainring [0075] 10 Toothed washer [0076] 11 Timing belts [0077] 12 Recuperation shaft [0078] 13 Generator [0079] 14 Timing belt tensioning device [0080] 15 Control unit [0081] 16 Sprocket [0082] 17 Protective housing [0083] 18 Rear wheel