Assembly for detecting a bearing force of a pedal bearing of a vehicle operatable with muscle and / or motor force

Abstract

The invention relates to an assembly (10) for detecting a bearing force of a pedal bearing (24) of a vehicle (100) that can be operated with muscle and / or motor forces, comprising a pedal bearing (24), a bearing receptacle (5), which surrounds the pedal bearing (24) at least partially annularly, a bearing force sensor (51), and a detection unit (6), a bending beam (53) that can be bent in the radial direction is formed on the bearing receptacle (5), the bearing force sensor (51) being provided for detecting a deformation of the bending beam (53), and wherein the bearing force sensor (51) is provided for detecting a deformation of the bending beam (53). The detection unit (6) is designed to detect a bearing force on the pedal bearing (24) on the basis of a deformation of the bending beam (53) detected by means of the bearing force sensor (51).

Description

Technical Field

[0001] The invention relates to a drive assembly of an electric bicycle, an electric bicycle comprising the drive assembly and a method for operating the drive assembly. Background Art

[0002] It is known that a vehicle that can be operated with muscle power and / or motor power, such as a drive assembly of an electric bicycle, has a drive unit that can generate a motor torque for assisting the pedaling force of the vehicle driver. Usually, the generation of the motor torque depends on the driver torque generated by the muscle power of the driver. For this purpose, it is necessary to detect the value of the driver torque currently generated, for example, by means of a corresponding sensor device. For example, it is also known that the force applied to the crank transmission by the driver can be obtained based on the bearing force on the pedal bearing of the electric bicycle and the drive unit can be operated based on this force. For example, such a system is shown in DE 10 2010 001 775 A1. Summary of the invention

[0003] In contrast, the component according to the invention having the features of claim 1 is characterized in that the bearing force on the pedal bearing of a vehicle that can be operated with muscle power and / or motor power can be precisely determined in a particularly simple and economical manner. In addition, for example, it is possible to simply determine the bearing force independently of the orientation of the drive unit, for example, on the frame of an electric bicycle. Based on the bearing force determined in this way, it is preferably possible to provide other functions of the drive component efficiently and economically. This is achieved by a component for detecting the bearing force of the pedal bearing of a vehicle that can be operated with muscle power and / or motor power, which component includes a pedal bearing, a bearing receiving portion that at least partially surrounds the pedal bearing in an annular manner, a bearing force sensor and a detection unit. In particular, the bearing receiving portion substantially completely surrounds the pedal bearing, preferably except for a predetermined gap area. The bearing receiving portion is particularly configured to hold the pedal bearing. For example, the bearing receiving portion can be configured as a bearing housing. Here, a bending beam that is particularly bendable in the radial direction on one side is configured on the bearing receiving portion. The bearing force sensor is configured here to detect deformation, i.e., particularly bending, of the bending beam. The detection unit is also configured to detect the bearing force on the pedal bearing based on the deformation of the bending beam detected by means of the bearing force sensor. In this case, the resulting force, which is generated, for example, due to the motor torque and / or the driver torque, is considered as the bearing force. Particularly preferably, the detection unit is configured to determine the bearing force direction and the bearing force value of the bearing force on the pedal bearing based on the detected deformation of the bending beam.

[0004] In other words, the present invention provides a component, which has a bearing receptacle on a pedal bearing, on which an at least partially bendable area in the form of a bending beam is arranged. As a result, the mechanical load acting on the pedal bearing is transferred from the pedal bearing to the bending beam, whereby the bending beam can deform. In particular, the bending beam is designed here to be freely movable in a radial direction on one side. This deformation can be detected by means of a bearing force sensor. The bearing force acting on the pedal bearing can then be determined by analyzing and evaluating the measured values ​​of the bearing force sensor by means of a detection unit. For example, the correlation between the deformation and the bearing force can be determined based on the known geometric and mechanical properties of the bearing receptacle and the pedal bearing. Alternatively or additionally, the bearing force can be determined based on a calibration of the system.

[0005] In this case, various types of sensors can be used as bearing force sensors, which are suitable for detecting the deformation of the bending beam. For example, the deformation can be detected directly and / or indirectly based on the force acting on the bending beam.

[0006] The arrangement thus offers the advantage that the bearing forces on the pedal bearing can be detected with a particularly simple, economical and space-saving design. The use of a bending beam makes it possible to provide a particularly sensitive design. In particular, since the ends of the bending beam are designed to be freely movable, even small bearing forces can lead to a deformation of the bending beam, which can be detected simply and precisely. This allows particularly small bearing forces to be determined very precisely. This has the advantage, for example, that small torque values ​​can be detected precisely and sensitively in an electric bicycle, thereby making it possible to control the drive unit particularly precisely as a function of the driver's torque.

[0007] The dependent claims contain advantageous developments of the invention.

[0008] Preferably, the subregion of the bearing receiving portion is configured as a bending beam that can be bent in the radial direction. That is, the bending beam is an integrated component of the bearing receiving portion itself. Therefore, a particularly simple design structure of the component can be provided.

[0009] The bearing receptacle preferably has a slot, in particular a radial slot. The bending beam adjoins the slot. In other words, the bending beam is formed by a sub-region of the bearing receptacle, so that the bearing receptacle is slotted, wherein the freely movable end adjoining the slot corresponds to the freely movable end of the bending beam. This makes it possible to provide a design that enables the advantageous properties of a sensitive bending beam in a particularly simple and economical manner.

[0010] Particularly preferably, the bearing receiving portion has two bending beams and each bending beam has a bearing force sensor. The two bending beams are preferably constructed symmetrically with respect to the gap and preferably have the same geometric properties. This makes it possible to detect the bearing force particularly accurately. For a particularly simple and economical configuration, the two bearing force sensors can preferably be structurally identical. The two bearing force sensors are preferably arranged in different directions so that bearing forces in different directions can be detected. Each of the two bearing force sensors is preferably configured and arranged so as to detect the force in the tangential direction relative to an axis, such as a pedal axis, a crank axis, an output shaft, etc., respectively. This makes it possible to provide a particularly simple and space-saving arrangement, which can also reliably determine the bearing force direction and the bearing force value of the total bearing force.

[0011] The component preferably also includes a stop, which limits the movement of the bending beam in the radial direction. In particular, the stop limits the maximum offset in the radial direction of the free end of the bending beam. Thus, a particularly high mechanical robustness of the component can be provided by means of a simple and economical design structure. In particular, the deformability of the bending beam can be limited to a maximum extent by means of the stop. As a result, for example, damage to the bearing receptacle can be avoided. In addition, a robust and reliable precise positioning of the pedal bearing is ensured by means of the bearing receptacle. In addition, the following advantage is provided by the stop: the bending beam can be designed optimally for a deformability that can be clearly and simply detected within a certain bearing force range. Thus, for example, a slight deformability of the bending beam at low bearing forces can be set for particularly sensitive detection, wherein excessive deformation is prevented by the stop.

[0012] It is further preferred that the stop is arranged such that, in the unloaded state of the pedal bearing, a predetermined air gap is formed between the free end of the bending beam and the stop. In the unloaded state, the air gap is preferably a maximum of 0.1 mm. As a result of the air gap, the bending beam is thus freely deformable up to the stop, so that the bearing forces can be detected particularly accurately based on this. The air gap can be adjusted in a particularly simple manner, for example, by correspondingly orienting the stop during assembly of the component.

[0013] The assembly preferably also comprises a housing. The bearing receptacle has a fastening region, which is fixed to the housing, in particular immovably fixed. The housing can be, for example, the housing of the drive unit. By fastening the bearing receptacle to the housing, an accurate, in particular immovable, retention of the pedal bearing relative to the housing is provided. The fastening region can be, for example, a section of the bearing receptacle, which corresponds in the circumferential direction to at least one third, preferably at least half, most preferably at most three quarters of the entire ring of the bearing receptacle.

[0014] The fastening region is preferably fixed to the housing by means of a threaded connection. In particular, the threaded connection comprises a plurality of screws distributed over the circumference of the bearing receptacle. Alternatively or additionally, the fastening region is preferably fixed to the housing by means of a welded connection and / or by means of an adhesive connection and / or by means of a press-fit connection. The welded connection and / or the adhesive connection is preferably formed over the entire surface of the fastening region in order to provide a particularly robust fixation.

[0015] It is further preferred that the assembly further comprises a fastening element, by means of which the fastening region is fastened to the housing. That is, the bearing receptacle is fastened directly or indirectly to the housing by means of the fastening element. This makes it possible to provide a particularly simple and economical production and assembly of the assembly, for example because it is possible to achieve a precise orientation of the bearing receptacle and the fastening element individually to the housing.

[0016] Particularly preferably, the fastening element is designed as a disk, which is preferably circular. The fastening element is arranged in particular together with the bearing receptacle in a recess of the housing. The recess preferably has an internal geometry that corresponds to the external geometry of the fastening element. This allows a particularly simple and economical design and assembly of the assembly. For example, the recess and the fastening element can have a geometry that can be manufactured simply and precisely.

[0017] The fastening region preferably forms at least a part of the outer circumference of the bearing receptacle. In particular, the bearing receptacle is fixed to the housing in such a way that the outer circumference of the bearing receptacle is at least partially fixed directly to the housing, preferably by means of a press-fit connection between the outer circumference and the housing. This makes it possible to provide a particularly simple, lightweight and economical design of the component. Furthermore, since, for example, the recess in the housing can be produced with high precision in a simple and economical manner, a particularly high positional accuracy of the bearing receptacle and thus of the pedal bearing can be provided. It can be particularly advantageous if the housing is a deep-drawn component, preferably a sheet metal housing, in which the recess is produced by deep drawing.

[0018] The bearing receiving portion is preferably arranged in the notch of the housing. Here, the radial outer dimension of the free end of the bending beam is smaller than the inner dimension of the notch of the housing by a predetermined gap dimension. In other words, the radial outer dimension of the free end of the bending beam is reduced by a predetermined gap dimension relative to the preferably circular outer contour of the fastening element. Preferably, the gap dimension is a maximum of 0.5 mm, preferably a maximum of 0.2 mm, in particular at least 0.01 mm. As a result, the housing constitutes a stop for the bending beam, in particular without a separate component for the stop. Therefore, a particularly simple and economical design structure with few components can be provided. Preferably, a stop area is provided on the free end of the bending beam, wherein a gap dimension is provided between the stop area and the housing. Preferably, there is a gap between the remaining area of ​​the bending beam and the notch, which gap is greater than the gap dimension, so that in particular the free mobility of the bending beam can be achieved and the bending beam is only abutted on the stop area.

[0019] The bearing receiving part preferably has a retaining area. At least one sub-area of ​​the retaining area and the edge of the housing notch are configured so that the sub-area of ​​the retaining area and the edge of the notch form an undercut in the radial direction. The retaining area is also arranged on the side of the free end of the bearing receiving part away from the bending beam. In other words, the bearing receiving part is configured so that the free end of the bending beam and the retaining area are arranged on the opposite side of the bearing receiving part. Here, the retaining area is so close to the housing that the position of the bearing receiving part is precisely defined relative to the bearing, especially along the direction extending from the free end to the retaining area. It is thus particularly reliably ensured that the predetermined gap size between the internal size of the notch and the free end of the bending beam is accurately followed. In addition, the gap size with low tolerance can be particularly reliably guaranteed in a simple and economical manner during manufacturing. The retaining area can, for example, have an area protruding at least radially outward from the annular base area of ​​the bearing receiving part and an area protruding from the area in the tangential direction.

[0020] Particularly preferably, the retaining region is annularly configured and substantially completely contacts the edge of the notch. In particular, the entire bearing receptacle thus has two annular sub-regions arranged adjacent to each other in the radial direction, wherein the sub-regions are connected to each other at the connection point to form an integral component. For example, the bearing receptacle can thus be configured in the shape of an "8". In particular, the connection point forms a narrowing of the outer circumference of the bearing receptacle, whereby an undercut (Hinterschneidung) with the housing can be provided in order to enable a precisely defined relative arrangement. As a result, an optimized position tolerance can be provided with regard to a particularly simple and economical design structure and manufacturability.

[0021] The holding area is preferably designed as a bearing seat for another bearing. In other words, the holding area is designed to receive another bearing, for example a bearing of a shaft of a transmission, for example a bearing of a preferably intermediate shaft of a multi-stage transmission. Thus, more functions can be fulfilled simultaneously with fewer components in a simple and economical manner.

[0022] The bearing force sensor preferably has a strain gauge. For example, by installing a strain gauge on a bending beam, its deformation can be detected particularly easily. For example, the strain gauge can be used to determine the tension and / or compression and based on this, the deformation and, for example, the mechanical force on the bending beam can be determined.

[0023] Alternatively or additionally, the bearing force sensor preferably has a piezoelectric element. Thus, the deformation and / or the currently acting force on the bending beam can be determined in a particularly simple, space-saving and economical manner, similar to a strain gauge.

[0024] Alternatively or additionally, the bearing force sensor preferably has a magnetic sensor. For example, the magnetic sensor can be a Hall sensor, in particular with the aid of which a relative position change of a subregion of the bending beam relative to another component, such as a housing, can be detected directly, simply and particularly accurately.

[0025] The present invention also relates to a vehicle that can be operated by muscle power and / or motor power, especially a drive assembly of an electric bicycle, including a crank transmission, which has a crank, an axis, such as a pedal axis and two pedal bearings for supporting the axis. In addition, the drive assembly includes an output element connected to the axis and a drive unit, which is arranged to provide a motor torque to assist the driver torque generated by the driver, especially by muscle power. Preferably, the chain plate is arranged as the output element. Alternatively, it is preferred to set another output element, which is arranged to be connected to the transmission element so that the torque can be transmitted from the axis to the driving wheel of the vehicle. The axis is supported in the drive unit by two pedal bearings. In addition, the drive assembly includes the above-mentioned assembly for detecting the bearing force on one of the two pedal bearings. The bearing force sensor is arranged at the height of the pedal bearing located on the output side along the axial direction of the axis. In other words, a drive assembly is provided, which has a bearing force sensor in the area of ​​the pedal bearing arranged near the output element of the two pedal bearings. The output element is preferably connected to the axis in a torsionally fixed manner. In particular, the axis is constructed in one piece here. The advantage here is that the bearing force is determined by means of a bearing force sensor, and the shaft can thus be designed particularly simply and economically, while the force for actuating the drive unit can nevertheless be reliably determined.

[0026] The bearing receiving part preferably has a retaining area of ​​annular design. In addition, the drive assembly also includes a transmission device with an intermediate shaft and an intermediate shaft bearing. For example, the transmission device can be designed as a multi-stage transmission device, in particular a spur gear transmission. The retaining area of ​​the bearing receiving part forms a bearing seat for the intermediate shaft bearing. That is, the intermediate shaft bearing is retained on the housing in a defined manner by the retaining area. As a result, a lightweight drive assembly can be provided with few components in terms of particularly simple and economical design and manufacturability, wherein particularly small tolerances can be observed when arranging the bearings and the shaft.

[0027] The present invention also relates to a vehicle that can be operated by muscle power and / or motor power, in particular an electric bicycle, which comprises the above-mentioned drive assembly.

[0028] The present invention also relates to a method for operating the above-mentioned drive assembly. The method comprises the following steps:

[0029] - Determine the deformation of the bending beam;

[0030] - Based on the determined deformation, the bearing force direction and the bearing force value of the total bearing force on the output-side pedal bearing are determined. The method is characterized by a particularly simple and economical implementability, wherein precise results can be determined for the bearing force direction and the bearing force value on the output-side pedal bearing.

[0031] The method preferably further comprises the step of determining the output force on the output element based on the bearing force direction and the bearing force value of the bearing force. In this case, the force exerted on the output element by the transmission element, for example a bicycle chain, is regarded as the output force, in particular during operation of the electric bicycle. The output force is preferably present on the outer circumference of the chain plate and extends in a predetermined direction along the bicycle chain, for example towards the rear wheel. Preferably, the output force is additionally determined based on known geometrical properties of the drive component, in particular the chain plate.

[0032] Further preferably, the method comprises the following steps: based on the determined output force and the motor torque, a driver torque applied by the driver is determined, in particular when the electric bicycle comprising a drive assembly is operated simultaneously with muscle force and motor force. In particular, the motor torque is known based on the drive control. Preferably, the driver torque is determined by determining the driver force, wherein the driver force corresponds to the portion of the output force generated by the driver's muscle force. In particular, the correlation between the driver torque and the driver force is defined by known geometrical properties of the drive assembly, in particular the chain plate. The driver force is preferably determined by subtracting the motor force from the total output force, wherein the motor force corresponds to the force acting on the bicycle chain generated by the motor torque. The driver torque can thus be determined in a particularly simple and precise manner.

[0033] The method preferably further comprises the following steps: controlling the motor torque generated by the drive unit according to the bearing force direction and the bearing force value. Particularly preferably, the drive unit is controlled according to the determined driver torque. That is, the motor torque is provided according to the bearing force or the driver torque determined based on the determined bearing force to assist the driver's pedaling force.

[0034] The bearing force direction and the bearing force value are preferably determined based on a calibration of the drive assembly. The calibration is performed by the ratio of the forces detected by the bearing force sensor during actuation of the crank mechanism in a predetermined calibration configuration. In the predetermined calibration configuration, the crank mechanism is actuated with an actuating force in a predetermined actuating direction. Particularly preferably, the calibration is performed by detecting a plurality of ratios in a plurality of different predetermined actuating directions. The calibration is preferably performed once when the drive assembly is mounted on the electric bicycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The present invention is described below according to the embodiments in conjunction with the accompanying drawings. In the accompanying drawings, components with the same functions are respectively marked with the same reference numerals. Here, it is shown:

[0036] Figure 1 : A simplified schematic diagram of an electric bicycle having a drive assembly according to a first embodiment of the present invention;

[0037] Figure 2 : Figure 1 A detailed cross-sectional view of a drive assembly;

[0038] Figure 3 : Figure 1 A partial stereoscopic view of a drive assembly;

[0039] Figure 4 : Figure 1 Another partial view of the drive assembly;

[0040] Figure 5 : Figure 1 A perspective view of details of the drive assembly;

[0041] Figure 6 : Figure 1 Another detailed view of the drive assembly;

[0042] Figure 7 : Figure 1 Another detailed view of the drive assembly of , with an alternative orientation of the drive unit;

[0043] Figure 8 : A detailed cross-sectional view of a drive assembly according to a second embodiment of the present invention;

[0044] Fig. 9 : Figure 8 A perspective view of details of the drive assembly;

[0045] Fig.10 : Fig. 9 Alternative stereoscopic views of details;

[0046] Fig.11 : A simplified schematic diagram of details of a drive assembly according to a third embodiment of the present invention;

[0047] Fig.12 : Fig.11 A perspective view of details of the drive assembly;

[0048] Fig.13 : Fig.11 Another perspective view of a detail of the drive assembly. DETAILED DESCRIPTION

[0049] Figure 1 A simplified schematic diagram of an electric bicycle 100 having a drive assembly 1 according to a first embodiment of the present invention is shown. Figure 2 Shown in a detailed cross-sectional view.

[0050] The drive assembly 1 has a crank gear 2 with two cranks 21 lying opposite each other relative to a pedal axis 22a. A pedal 25 is arranged on the crank 21, through which the driver can generate a driver torque on the drive assembly 1 by means of muscle force.

[0051] Furthermore, the crank gear 2 comprises a shaft, for example a pedal shaft 22 , which is connected to the crank 21 in a rotationally fixed manner, and two pedal bearings 23 , 24 for rotatably supporting the pedal shaft 22 .

[0052] The drive assembly 1 further comprises an output element 3 which is a chain plate and is connected to the pedal shaft 22 in a rotationally fixed manner, and a bicycle chain 7 as a transmission element which engages with the chain plate 3 .

[0053] In order to assist the driver torque with an additional motor torque, the drive assembly 1 comprises a drive unit 4 which is provided for generating a motor torque, preferably by means of an electric motor which is supplied in particular by an electrical energy storage device (not shown).

[0054] The drive unit 4 is preferably fastened to a bicycle frame 101 of the electric bicycle 100 .

[0055] The pedal shaft 22 is supported in the drive unit 4 by means of two bearings 23, 24. In this case, the drive unit 4 has a bearing flange 43 on the bearing 23 facing away from the output side, in which the bearing 23 is arranged (see Figure 2 ). In particular, the bearing flange 43 is an integral component of the housing 40 of the drive unit 4 .

[0056] During motor-assisted operation of the electric bicycle 100 , the motor torque is adapted as a function of the driver torque applied by the driver. As described below, the driver torque is determined by determining the bearing force 59 at the output-side pedal bearing 24 .

[0057] In order to determine the driver torque based on the bearing force 59, a number of known mechanical and geometric relationships are used as well as the motor torque known from the operation of the drive unit 4. Specifically, the following relationship is used here: the output force 60 that is important for the forward drive of the electric bicycle 100 causes a reaction force on the output-side pedal bearing 24 with the same value and parallel thereto in the opposite direction.

[0058] Knowing the geometry and mechanical properties of the crank mechanism 2 and the motor torque of the drive unit 4, the portion of the output force 60 applied by the drive unit 4, i.e. the motor force, can be determined. Thus, by subtracting the motor force from the total output force 60, the driver force can be determined in a simple manner, which corresponds to the portion of the output force 60 applied by the driver's muscle force. Subsequently, the corresponding driver torque can also be determined in a simple manner via the geometric properties of the drive assembly 1.

[0059] Here, in the present drive assembly 1, the bearing force 59 is determined by means of a simple, compact and cost-effective design which also allows particularly sensitive and precise detection. For this purpose, the drive assembly 1 has two bearing force sensors 51, 52 arranged in the region of the pedal bearing 24 on the output side.

[0060] exist Figure 3 and Figure 4 2 shows the arrangement of two bearing force sensors 51 , 52 . In this case, the two bearing force sensors 51 , 52 are located at the height of the output-side pedal bearing 24 in the axial direction of the pedal shaft 22 .

[0061] Each of the two bearing force sensors 51 , 52 is designed as a strain gauge and is provided to detect forces 55 , 56 caused, for example, by mechanical tension and / or compression in precisely one predetermined direction, namely in a radial direction relative to the pedal axis 22 a .

[0062] The two bearing force sensors 51 , 52 are connected to a detection unit 6 which determines the forces 55 , 56 and also carries out the determination of all other forces and moments.

[0063] The bearing force sensors 51, 52 are arranged radially outside the bearing receptacle 5. The bearing receptacle 5 is a component manufactured separately from the housing 40 of the drive unit 4 and is in particular designed as a bearing shell. In the first embodiment, the bearing receptacle 5 has a substantially square outer geometry.

[0064] exist Figure 5 A perspective view of the bearing receptacle 5 is shown in FIG.

[0065] The footrest bearing 24 is arranged in a recess of the bearing receptacle 5 , wherein in the unloaded state, the entire inner circumference of the bearing receptacle 5 is preferably substantially in contact with the outer circumference of the footrest bearing 24 .

[0066] The bearing receptacle 5 is also slotted, having a slot 57 which extends completely through the entire bearing receptacle 5 in the radial direction.

[0067] The bearing receptacle 5 also has a fastening region 50, which is fastened to the housing 40. The fastening region 50 is the axial end side of the bearing receptacle 5, which is in full contact with the housing 40. In the first embodiment, the fastening region 50 is fixed to the housing 40 by means of a total of three screw connections 58a.

[0068] Furthermore, the bearing receptacle 5 has two bending beams 53 which are arranged respectively between the slot 57 and the fastening region 50. The bending beams 53 are designed such that they can be deformed in the radial direction. Figure 4 In FIG. 5 , the bending beam 53 is marked with hatching.

[0069] On the radial outer side of each bending beam 53 there is a respective flat flattened portion 41 on which the corresponding bearing force sensor 51 , 52 is arranged.

[0070] If the crank drive 2 is loaded by the pedaling force of the rider, this causes a bearing force 59 on the pedal bearing 24. Since the pedal bearing 24 is held in the housing 40 of the drive unit 4 by means of the bearing receptacle 5, the bearing force 59 acts accordingly on the bearing receptacle 5. Due to the special configuration of the bearing receptacle 5 with the movable bending beam 53, the bearing force 59 leads to a deflection of the bending beam 53 in the radial direction. This deformation can be detected by means of bearing force sensors 51, 52 designed as strain gauges.

[0071] Based on the known geometric and mechanical properties of the component 10 described above, the total resultant bearing force 59 , ie the bearing force direction and the bearing force value, can be determined based on the detected deformation.

[0072] Due to the free mobility of the bending beam 53 in the radial direction, a particularly sensitive detection can be achieved in the case of an appropriate mechanical design. For example, by appropriately designing the thickness of the bending beam 53 in the axial and / or radial direction, it can be achieved that a clearly measurable deformation occurs even in the case of low bearing forces. In particular, low torques applied by the driver can thus be detected with high precision.

[0073] In order to ensure a particularly high degree of precision by means of a deformation of the bending beams 53 which is as unaffected as possible, the bending beams 53 are spaced apart in the axial direction from the housing wall, against which the fastening region 50 of the bearing receptacle 5 rests. That is, in the axial direction there is a gap between the axial end side 50b of each bending beam 53 which faces the housing wall and the housing wall against which the end side 50a of the fastening region 50 rests. As a result, the deformation of the bending beams 53 is not affected, for example, by friction.

[0074] Furthermore, the bending beam 53 and / or the pedal bearing 24 can be constructed so that a region with as low a friction as possible is formed between the radial inner side of the bending beam 53 and the radial outer side of the pedal bearing 24, so that, for example, distortion of the measurement results due to stress caused by adhesion can be avoided or reduced.

[0075] Furthermore, the assembly 10 comprises a stop 7 which limits the movement of each bending beam 53 in the radial direction. The stop 7 is fixed immovably to the housing 40 of the drive unit 4. The stop 7 is located in the extension of the slot 57 and each bending beam 53 has a stop surface 75, against which the free end 53a of the bending beam 53 can essentially rest in the radial direction when the bending beam 53 is deformed in the radial direction. In particular, in the unloaded state, the stop surface 75 is arranged parallel to the flattened portion 41 of the bending beam 53.

[0076] The stop 7 is designed and fastened to the housing 4 in such a way that in the unloaded state, i.e. when the footrest bearing 24 is unloaded, a predetermined air gap 70 is present between each free end 53a or each flattened portion 41 of each bending beam 53 and the respective stop surface 75. As a result, the bending beam 53 can be deformed completely freely until it abuts against the stop 7. The stop 7 can provide the assembly 10 with a particularly high mechanical robustness.

[0077] In order to be able to determine the output force 60 acting on the bicycle chain 7 from the determined bearing force 59 and thus also the driver torque as described above, it is necessary to know the relative orientation of the chain direction 70 of the bicycle chain 7 and the drive unit, i.e. the installation position of the drive unit 4 on the bicycle frame 101. This is based on Figure 6 and Figure 7 For intuitive illustration, the two figures show different installation positions of the drive unit 4 .

[0078] As in Figure 6 and Figure 7 , there are different orientations of the chain direction 70 and the drive unit 4 relative to one another. In order to be able to correctly determine the output force 60 based on the bearing force 59, it is therefore necessary to know the geometric relationship between the drive unit 4 and the chain direction 70.

[0079] For this purpose, a calibration is performed on the drive assembly 1. During the calibration, no motor torque is generated by the drive unit 4.

[0080] During calibration, in a first step, the crank transmission 2 can be arranged so that the crank 21 is oriented horizontally, i.e. parallel to the chain direction 70. In this first calibration configuration, exactly one crank 21, i.e. the crank 21 pointing forward in the direction of travel, is actuated with an actuating force. The actuating force is here oriented vertically, i.e. orthogonally, to the crank 21 and the chain direction 70 and is applied by the driver actuating the pedal. Thus, the entire actuating force is transmitted to the bicycle chain 7. The corresponding bearing force 59 corresponds here to the resultant force caused by the actuating force and the output force 60. Preferably, the calibration is performed after the drive unit 4 is assembled in the bicycle frame 101 of the electric bicycle 100. It is particularly preferred to actuate the crank 21 with a predetermined, exactly known actuating force so that the value of the output torque can be accurately determined.

[0081] In the second step of the calibration, the crank drive 2 is arranged so that the crank 21 is oriented perpendicularly, i.e. orthogonally, to the chain direction 70. In this second calibration configuration, the lower crank 21 is actuated with an actuating force which is also oriented perpendicularly, i.e. orthogonally, to the chain direction 70 and parallel to the crank 21. As described above, the actuating force is applied by the driver actuating the pedal 25. In this second actuating configuration, the output force 60 is zero due to the corresponding orientation of the crank drive 2. The bearing force 59 is still caused by the actuating force.

[0082] Based on the forces 55, 56 of the bearing force sensors 51, 52 respectively detected in the two calibration steps, the orientation of the bearing force sensors 51, 52 relative to the known position of the crank 21 and / or the bicycle chain 7 can therefore be derived from the ratio of the two forces 55, 56. Thus, the orientation of the drive unit 4 relative to the bicycle chain 7 can also be determined. The orientation determined in this way can then be used as a basis for determining the driver torque for the bearing force direction and the bearing force value based on the bearing force 59.

[0083] Figure 8 A detailed sectional view of a drive assembly 1 according to a second embodiment of the invention is shown. The second embodiment corresponds essentially to the first embodiment, but has an alternative configuration of the fastening and arrangement of the bearing receptacle 5 in the housing 40 of the drive unit 4. Fig. 9 and Fig.10 2 shows further detailed views of the drive assembly 1 of the second embodiment.

[0084] In the second embodiment, the bearing receiving portion 5 is arranged in a recess 65 of the housing 4. The recess 65 is circular and is arranged coaxially with the pedal axis 22a. The recess 65 can be, for example, Figure 8 The stepped structure can be seen in FIG. 4 and extends completely through the wall of the housing 4. Figure 8 The pedal shaft 22 (not shown) extends completely through the recess 65 of the housing 4.

[0085] Furthermore, in the second exemplary embodiment, the assembly 10 comprises a separate fastening element 60, by means of which the bearing receptacle 5 is fixed in the housing 4. The fastening element 60 is a circular annular disk which can consist of metal, for example.

[0086] The bearing receptacle 5 is fixed to the fastening element 60 at the fastening region 50 by means of a welded connection 58b. Here, the welded connection 58b extends over the entire fastening region for a secure and reliable connection. Similar to the first embodiment, there is a small axial gap between the bending beam 53 of the bearing receptacle 5 and the fastening element 60 for unimpeded mobility of the bending beam 53.

[0087] The fastening element 60 has an outer diameter which corresponds to the inner diameter of the recess 65 .

[0088] The fastening element 60 is fixed immovably on the housing 40 , for example by means of a press fit and / or by means of a welded connection and / or by means of an adhesive connection. Thus, the bearing receptacle is indirectly fastened to the housing 40 of the drive unit 4 by means of the fastening element 60 .

[0089] The bearing receptacle 5 is designed and fixed to the fastening element 60 in such a way that the radial outer dimension 53b of the free end 53a of the bending beam 53 is smaller than the outer dimension of the fastening element 60 and thus also the inner dimension 65a of the recess 65 by a predetermined gap dimension 53c (see Fig. 9 ). As a result, the inner circumference of the notch 65 acts as a stop. That is, if one of the bending beams 53 is deformed radially outward due to the bearing force 59, the deformation is limited by the free end 53a of the bending beam 53 abutting against the inner circumference of the notch 65. As a result, a particularly simple and lightweight design structure of the drive assembly 1 can be provided. In addition, the drive assembly can be manufactured particularly simply and cost-effectively.

[0090] Fig.11 A simplified schematic diagram showing details of a drive assembly 1 according to a third embodiment of the invention. Fig.12 and Fig.13 1 shows further views of the drive assembly 1 of the third embodiment. The third embodiment corresponds essentially to Figures 8 to 10 The second exemplary embodiment of the present invention differs in the alternative configuration of the bearing receiving part 5 and the housing 40 .

[0091] In the third embodiment, the housing 40 is preferably constructed as a full sheet metal housing. In other words, the housing 40 is composed of one or more deep-drawn components. The recess 65 in which the bearing receptacle 5 is arranged is formed by a deep-drawing process. Fig.12 Can be seen in.

[0092] In the third embodiment, the bearing receiving part 5 additionally has a retaining area 54, which is annularly configured. The retaining area 54 and the likewise annularly configured base area of ​​the bearing receiving part 5 (which forms the bearing seat of the pedal bearing 24) together form an integral component, which is essentially configured in the shape of an "8".

[0093] The holding area 54 has a further recess 54b, which is in particular designed as a circular through hole. The recess 54 is coaxial with the intermediate shaft axis 22b, which is parallel to the pedal axis 22a.

[0094] The housing 40 and the bearing receptacle 5 are designed in this case such that an inner edge 65 b of the recess 65 of the housing 40 contacts the outer circumference of the holding region 54 substantially completely, in particular by means of a press-fit connection.

[0095] Due to the "8"-shaped geometry of the bearing receptacle 5 and the recess 65 of the housing 40, an undercut is present in a plane perpendicular to the pedal axis 22a and along a direction 22d corresponding to the straight line connecting the two axes 22a, 22b. Fig.11 It is indicated by reference numeral 54a.

[0096] Therefore, in the third embodiment, the position of the bearing receiving portion 5 in the housing 40 is precisely and clearly fixed by the outer periphery of the bearing receiving portion 5 and by the inner edge 65b of the notch 65. In particular, in the third embodiment, the outer periphery of the bearing receiving portion 5 thus forms a fastening area 50 for fixing the bearing receiving portion 5 on the housing 40.

[0097] Due to the special geometry with undercut 54a in direction 22d, a precisely defined relative position of bearing receptacle 5 and housing 40 can be achieved in a particularly simple and cost-effective manner with few components. In particular, a special geometry with a clearance dimension 53c can be achieved thereby, i.e. the free end 53a of the bending beam 53 of the bearing receptacle 5 is arranged with a predetermined clearance dimension 53c relative to the inner dimension 65a of the recess 65 of the housing 40.

[0098] The recess 54b of the retaining region 54 of the bearing receptacle 5 forms a further bearing seat for a further (not shown) bearing. Preferably, the further bearing seat is a bearing seat for an intermediate shaft bearing, by means of which an intermediate shaft of a transmission (not shown) of the drive assembly 1 can be supported. Thus, the integration of multiple functions can be achieved in a particularly simple and cost-effective manner with particularly small bearing tolerances.

[0099] In particular, the recess 54 b can be provided here as a bearing seat for any bearing of any shaft.

[0100] As in Fig.12 It can be seen in FIG. 4 that the recess 65 of the housing 40 is configured with a plurality of different sub-regions. The retaining region recess 65d is provided for receiving the retaining region 54 of the bearing receptacle 5. The retaining region recess 65d is configured as a recess which does not completely penetrate the housing 40.

[0101] In the region of the base region of the bearing receptacle 5 which is provided as a bearing seat for the pedal bearing 24, the recess 65 has a first flange 65c which is similar to Figures 8 to 10 (See especially Fig.10 ) is configured as the fastening region 50 of the second embodiment of the present invention, and the bearing receiving portion 5 is flatly attached to the first flange. In addition, the notch 65 has a second flange 65b, which is deeper than the first flange 65c, in order to prevent mechanical contact between the bearing receiving portion 5 and the housing 40 in this area. In addition, the notch 65 has a through hole for passing the pedal shaft 22.

[0102] exist Fig.13 , a completely assembled assembly consisting of a bearing receptacle 5 and a housing 40 is shown by way of example. In this case, the bearing receptacle 5 is pressed into a recess 65 of the housing 40 and is subsequently fixed in the housing in an axial direction, in particular in a form-fitting manner, by means of a plurality of fastening regions 5c. The fastening regions 5c are preferably formed by plastically deforming a sub-region of the housing 40, for example by means of locking. As a result, the drive assembly 1 can be assembled in a particularly simple, efficient and cost-effective manner.

Claims

1. A component for detecting the bearing force of a pedal bearing (24) of a vehicle (100) capable of being operated by muscle force and / or motor force, include: - footrest bearing (24), a bearing receptacle (5) which at least partially annularly surrounds the pedal bearing (24), - a bearing force sensor (51), and - a detection unit (6), - wherein a bending beam (53) is formed on the bearing receiving portion (5) and is bendable in the radial direction, - wherein the bearing force sensor (51) is arranged to detect the deformation of the bending beam (53), and - wherein the detection unit (6) is configured to detect the bearing force on the pedal bearing (24) based on the deformation of the bending beam (53) detected by means of the bearing force sensor (51).

2. The assembly according to claim 1, in, A subregion of the bearing receptacle (5) is designed as a bending beam (53) that is bendable in the radial direction.

3. An assembly according to any one of the preceding claims, in, The bearing receptacle (5) has a slot (57), in particular a radial slot, and the bending beam (53) adjoins the slot (57).

4. An assembly according to any one of the preceding claims, in, The bearing receptacle (5) has two bending beams (53) and a bearing force sensor (51, 52) is provided for each bending beam (53).

5. Assembly according to any one of the preceding claims, further comprising a stop (7) which limits the movement of the bending beam (53) in a radial direction.

6. The assembly according to claim 5, in, The stop (7) is arranged such that, in the unloaded state of the pedal bearing (24), a predetermined air gap (70) is arranged between the free end (53a) of the bending beam (53) and the stop (7).

7. An assembly according to any one of the preceding claims, further comprising a housing (40), in, The bearing receptacle (5) has a fastening region (50) which is fixed to the housing (40).

8. The assembly according to claim 7, in, The fastening region (50) is fixed to the housing (40) by means of a screw connection (58a) and / or by means of a welded connection (58b) and / or by means of an adhesive connection and / or by means of a press-fit connection.

9. The assembly according to claim 7 , further comprising a fastening element ( 60 ) by means of which the fastening region ( 50 ) is fixed to the housing ( 40 ), in particular in, The fastening element (60) is designed as a disk, in particular as a circular disk.

10. The assembly according to claim 7 or 8, in, The fastening area (50) is at least a portion of the outer circumference of the bearing receiving portion (5).

11. The assembly according to any one of claims 7 to 10, in, The bearing receiving portion (5) is arranged in a recess (65) of the housing (4), and wherein a radial outer dimension (53b) of a free end (53a) of the bending beam (53) is smaller than an inner dimension (65a) of the recess (65) of the housing (4) by at least a predetermined gap dimension (53c).

12. The assembly according to claim 11, in, The bearing receptacle (5) has a retaining area (54), wherein at least a sub-area of ​​the retaining area (54) and an edge (65b) of a recess (65) of the housing (40) form an undercut in the radial direction, and wherein the retaining area (54) is arranged on a side of the bearing receptacle (5) facing away from a free end (53a) of the bending beam (53).

13. The assembly according to claim 11, in, The retaining region (54) is annular in shape and substantially completely contacts the edge (65a) of the recess (65).

14. The assembly according to claim 13, in, The retaining area (54) is designed as a bearing seat for a further bearing.

15. Assembly according to any one of the preceding claims, in, The bearing force sensor (51) has a strain gauge and / or a piezoelectric element and / or a magnetic sensor.

16. A drive assembly for a vehicle (100) capable of being operated by muscle power and / or motor power, include: - a crank transmission (2) having a crank (21), a shaft (22) and two pedal bearings (23, 24) for supporting the shaft (22), - an output element (3), which is connected to the shaft (22), a drive unit (4) arranged to provide a motor torque to assist a driver torque applied by a driver, - wherein the shaft (22) is supported in the drive unit (4) by means of two pedal bearings (23, 24), and - an assembly according to any one of the preceding claims, - wherein the bearing force sensor (51) is arranged in the axial direction of the shaft (22) at the height of the pedal bearing (24) on the output side.

17. The drive assembly according to claim 16, in, The bearing receptacle (5) has the retaining region (54) which is annularly designed, and the drive assembly further comprises a transmission having an intermediate shaft and an intermediate shaft bearing, wherein the retaining region (54) forms a bearing seat for the intermediate shaft bearing.

18. A vehicle capable of being operated by muscle power and / or motor power, comprising a drive assembly (1) according to claim 16 or 17.

19. A method for operating a drive assembly (1) according to claim 16 or 17, The following steps are involved: - determining the deformation of the bending beam (53), and - Based on the determined deformation, the bearing force direction and the bearing force value of the bearing force (59) on the output-side pedal bearing (24) are determined.

20. The method according to claim 19, further comprising: The following steps are involved: - determining an output force (60) on the output element (3) based on the bearing force direction and the bearing force value of the bearing force (59), and - determining a driver torque applied by the driver based on the output force (60) and the motor torque of the drive unit (4).

21. The method according to any one of claims 19 or 20, further comprising: The following steps are involved: - controlling the motor torque generated by the drive unit (4) according to the bearing force direction and the bearing force value.

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