TRAILER FOR A BICYCLE

Abstract

The invention relates to a trailer (2) for a bicycle (1), having a braking device acting on wheel(s) (4) of the trailer (2); a sensor device (12) which supplies a measured variable, which is a measure of an acceleration force acting on the trailer (2) via a tow bar (5); a controller (18) for controlling the braking device and that is configured to act on the braking device, depending on the measured variable determined by the sensor device (12), such that an inertial force of the trailer (2) generated in the pulling mode or during braking of the bicycle (1) is compensated for or is at least reduced; and a decoupling device (10; 410; 510) which is configured for the partial mechanical decoupling of a movement of the bicycle trailer (2) with respect to the bicycle (1) in the longitudinal direction of the bicycle trailer (L).

Claims

1-15. (canceled)

16. A trailer for a bicycle, comprising: a braking device acting on at least one wheel of the trailer; a sensor device, which supplies a measured variable that is a measure of an acceleration force acting on the trailer via a tow bar; a controller for controlling the braking device of the trailer, that is configured to control the braking device, depending on the measured variable determined by the sensor device, in such a manner that an inertial force of the trailer generated during braking of the bicycle is compensated for or is at least reduced; and a decoupling device which is configured for a partial mechanical decoupling of a movement of the bicycle trailer with respect to the bicycle in a longitudinal direction of the bicycle trailer.

17. The trailer according to claim 16, further comprising an electric drive to drive the trailer, wherein the controller is further configured to accelerate the trailer by way of the electric drive, dependent on the measured variable determined by the sensor device, in such a manner that an inertial force of the trailer generated during traction mode of the bicycle is compensated for or is at least reduced.

18. The trailer according to claim 16, wherein the sensor device is provided on the decoupling device.

19. The trailer according to claim 16, wherein the sensor device comprises at least one member selected from the group consisting of a wire resistance strain gauge, a Hall effect sensor and a piezoelectric bending beam sensor.

20. The trailer according to claim 16, wherein the decoupling device comprises limit stop means, which limit any movement of the bicycle trailer relative to the bicycle to a predetermined maximum value.

21. The trailer according to claim 16, wherein a trailer-side end of the tow bar is attached to the trailer body with the decoupling device.

22. The trailer according to claim 16, wherein the decoupling device is provided with a spring damping function.

23. The trailer according to claim 16, wherein the decoupling device comprises two bending elements, which are each attached at one end to the trailer body and at an opposite end to the tow bar, extend across the longitudinal direction of the trailer and are bendable in the longitudinal direction of the trailer.

24. The trailer according to claim 23, wherein the sensor device comprises a piezoelectric bending beam sensor that is arranged parallel to a bending element in such a manner that said piezoelectric bending beam sensor performs a deflection corresponding to the bending element.

25. The trailer according to claim 23, wherein the sensor device is executed as a Hall effect sensor, that is configured to measure the deflection of the bending elements.

26. The trailer according to claim 23, wherein the sensor device has at least one wire resistance strain gauge attached to one of the bending elements.

27. The trailer according to claim 23, wherein the two bending elements are plate-shaped.

28. The trailer according to claim 16, wherein the decoupling device comprises: (a) two pivot arms, which are each rotatably attached to the trailer body at one end and rotatably attached to the tow bar at an opposite end and extend across the longitudinal direction of the trailer, and (b) a bending body, which is attached to the trailer body at one end and to the tow bar at the opposite end, extends across the longitudinal direction of the trailer and is bendable in the longitudinal direction.

29. The trailer according to claim 23, wherein limit stops are provided, said limit stops being arranged offset to the bending elements in the longitudinal direction of the trailer in such a manner that a deflection of the bending elements is limited in the longitudinal direction by the limit stops.

30. The trailer according to claim 28, wherein limit stops are provided, said limit stops being arranged offset to the pivot arms in the longitudinal direction of the trailer in such a manner that a deflection of the pivot arms is limited in the longitudinal direction by the limit stops.

31. The trailer according to claim 16, wherein the decoupling device comprises at least one spring that is deflectable in the longitudinal direction.

32. The trailer according to claim 16, wherein the electric drive is executed as a wheel hub motor.

33. The trailer according to claim 16, wherein the braking device is executed as an electrically operated mechanical brake.

34. The trailer according to claim 17, wherein the braking device of the trailer is designed as an electrical machine acting as a motor and also as a brake and constitutes the electric drive in motorized mode.

35. The trailer according to claim 17, wherein the trailer has an electrical energy storage device to supply the electric drive.

36. The trailer according to claim 16, wherein the sensor device is configured to determine a deflection of a moving element of the decoupling device, said deflection of the moving element being a measure for an acceleration force acting on the trailer via the tow bar.

37. The trailer according to claim 16, wherein the sensor device comprises a force sensor that is designed to measure the acceleration force acting on the decoupling device.

Description

[0045] The preferred embodiments described above and features of the invention can be combined with each other as needed. Further details and advantages of the invention are described below with reference to the attached drawings. The figures show:

[0046] FIG. 1 a schematic plan view onto a vehicle combination comprising a bicycle and a trailer according to an embodiment of the invention;

[0047] FIG. 2 a side view of FIG. 1;

[0048] FIG. 3 a schematic plan view onto a vehicle combination comprising a bicycle and a trailer according to a further embodiment of the invention;

[0049] FIG. 4 a detailed view of a decoupling device according to the invention in accordance with one embodiment; and

[0050] FIG. 5 a detailed view of a decoupling device according to the invention in accordance with a further embodiment.

[0051] FIG. 1 shows a schematic plan view onto a vehicle combination comprising a bicycle 1 and a trailer 2. The trailer 2 is fastened to the bicycle in a coupling region 9, via a tow bar 5, at the free end of which a trailer coupling (not shown) is provided. The bicycle 1 has a corresponding coupling for this purpose and is designed in a conventional manner.

[0052] In the illustrated embodiment, the trailer 2 is provided with two wheels 4, which have electric wheel hub motors 20.

[0053] The structure of the bicycle trailer 2 without tow bar 5 is referred to in the present document as the trailer body 3. Electrically operated mechanical wheel brakes 8 are arranged on the two wheels 4 and are controlled by an electronic control device configured as a feedback controller 18. The trailer 2 further carries an energy storage device 19, which can be executed in the form of a conventional battery for a so-called E-bike and can be connected via the controller 18 to the electrical machines in the form of the wheel hub motors 20 of the trailer 2.

[0054] A decoupling device 10, which is designed for the partial mechanical decoupling of a movement of the bicycle trailer 2 relative to the bicycle 1 in the longitudinal direction of the bicycle trailer, illustrated by the arrow marked L, is provided at the trailer-side end of the tow bar 5.

[0055] The highly schematized view in FIG. 1 shows the elements of the decoupling device 10 in a functional rather than in a structural representation. Via the decoupling device 10, the tow bar 5 is fastened in a sprung and damped manner onto the trailer body 3, for example onto the trailer frame, by means of its trailer-side end region 7.

[0056] Here the damping property of the decoupling device is represented by the damper 13 and the spring-like property of the decoupling device 10 by the spring 14. Structurally, the spring-like and damping property can be realized in one component with spring-like and damping properties, as is explained below in more detail with reference to further exemplary embodiments.

[0057] By means of the decoupling device 10, the tow bar is therefore partially mechanically decoupled from the trailer body 3, so that the trailer body 3 can move to a limited extent in the longitudinal direction L relative to the tow bar and to the bicycle 1. A sensor device 12, for example a force sensor, which supplies a measured variable that is a measure of the acceleration force acting on the trailer 2 via a tow bar 5, is provided in the decoupling device 10.

[0058] Measurement signals from the sensor device 12 are transmitted to the electronic controller 18 via an input signal line 16. The controller 18 is part of a control loop and is configured to act on the braking device 8, dependent on (as a function of) the transmitted measured variable of the sensor device 12, in such a manner that an inertial force of the trailer 2 generated during braking of the bicycle 2 is compensated for or is at least reduced. To this end, the controller 18 continuously outputs corresponding corrective signals to the brakes 8 via corresponding output signal lines 17.

[0059] The controller 18 is further configured to accelerate the trailer 2, dependent on (as a function of) these measured variables, by activating the wheel hub motors 20 in such a manner that an inertial force of the trailer generated during traction mode of the bicycle is compensated for or is at least reduced. To this end, the controller 18 continuously outputs corresponding corrective signals to the wheel hub motors 20 via corresponding output signal lines 17.

[0060] The controller 18 is preferably configured such that, in drive mode, it adjusts the wheel hub motors 20 and the brakes 8, as a function of the control variable continuously measured by the sensor device, so that the force in the tow bar 5 is controlled to zero.

[0061] FIG. 2 shows a schematic side view of FIG. 1. Reference numeral 11 designates the attachment point of the decoupling device 20 on the trailer body 3. It can further be seen from the illustration in FIG. 2, that two limit stops 15 are fastened to the side of the trailer body 3, offset in the longitudinal direction L to the end region 7 of the tow bar 5, said limit stops limiting a relative movement of the tow bar 5, 7, that is facilitated by the decoupling device 10, along the trailer body 3 both in and against the direction of travel.

[0062] On a pulling movement of the bicycle 1, the left side 7a of the end region 7 of the tow bar 5, shown in FIG. 2, hits the left limit stop 15, while, when the bicycle brakes, the right side 7a hits the right limit stop 15, thereby limiting the movement of the trailer relative to the bicycle.

[0063] FIG. 3 shows a further embodiment. In this embodiment, components with the same reference numerals correspond to the components in FIG. 1 and are not described separately. The particular feature of this embodiment is that an electrically operated mechanical wheel brake 8 and a wheel hub motor 20, which, as described above, are controlled by the controller 18, are provided on one wheel only.

[0064] FIG. 4 shows a detailed view of an embodiment 410 for structural implementation of the decoupling device 10. The decoupling device 410, once again shown in highly schematized form, is realized by means of two bending plates 411, which are made from carbon or a carbon composite. The bending plates 411 are non-rotatably fixed at one end to the trailer body 3, for example to the trailer frame, and at the opposite end to the tow bar 5, especially at the trailer end region 7 of the tow bar 5. The bending plates 411 have low stiffness in the direction of travel or longitudinal direction L and, as a result, can bend transverse to the longitudinal direction L of the trailer, thereby creating the translational degree of freedom.

[0065] The spring stiffness and desired damping are adjusted by the appropriate choice of the geometry and material of the plates 411. Thus the bending plates 411 constitute the functional components 11, 13 and 14 in FIG. 1.

[0066] The broken lines illustrate a state of the decoupling device 410 under the effect of a braking force generated by the bicycle 1 acting on the tow bar 7, so that the trailer 2 or the trailer body 3 shifts in the direction of travel relative to the bicycle (not shown).

[0067] The corresponding deflection of the bending plates 411 can be measured by at least one piezoelectric bending beam sensor (not shown) arranged parallel to the bending plates 411, so that the piezoelectric bending beam sensor is subject to a deflection corresponding to the deflection of the bending plates 411. The charge displacement of the integrated piezoelectric element is dependent upon the deflection of the piezoelectric bending beam sensor and can therefore serve as a measure for the acceleration force acting on the trailer 2 via the tow bar 5.

[0068] FIG. 5 shows an alternative embodiment 510 for the decoupling device 10.

[0069] According to this embodiment, the decoupling device 510 comprises two pivot arms 511, which are each rotatably attached via low-friction rotary bearings to the trailer body 3 at one end and rotatably attached to the tow bar 7 at the opposite end and extend across the longitudinal direction L of the trailer 2.

[0070] Arranged centrically between the two pivot arms 511 is a bending body 513, which is likewise fixed at one end to the trailer body 3 and at the opposite end to the tow bar 7. Thus the bending body 513 likewise extends across the longitudinal direction L of the trailer 2 and is bendable in the longitudinal direction L.

[0071] The spring stiffness and damping of the decoupling device 510 is achieved by means of the additional bending body 513, which undergoes shearing stress under the effect of an acceleration force, while in this case the pivot arms 511 swivel in parallel. This is represented in turn in FIG. 5 by the broken lines. As already mentioned above, a particular advantage of this embodiment is that the load-bearing mechanical elements 511 in the form of the pivot arms are hardly subject to any stress. If the comparatively highly stressed bending body 513 were to be damaged, the tow bar 5, 7 would continue to be firmly connected to the trailer 3 via the pivot arms 511.

[0072] Although the invention has been described with reference to specific embodiments, it is obvious to a person skilled in the art that various modifications can be made and equivalents substituted without departing from the scope of the invention. Additionally, many modifications can be made without departing from the related scope. Consequently the invention should not be restricted to the disclosed embodiments but should rather encompass all embodiments that fall within the scope of the attached claims.