CN215598587U

CN215598587U - Torque sensor and electric power-assisted vehicle

Info

Publication number: CN215598587U
Application number: CN202121614877.1U
Authority: CN
Inventors: 不公告发明人
Original assignee: Beijing Zero Innovation Technology Co ltd
Current assignee: Beijing Zero Innovation Technology Co ltd
Priority date: 2021-07-15
Filing date: 2021-07-15
Publication date: 2022-01-21
Anticipated expiration: 2031-07-15

Abstract

The embodiment of the utility model provides a torque sensor and an electric power-assisted vehicle. The torque sensor includes a housing; the torque transmission piece is used for being connected with the torque input piece so as to transmit the torque input by the torque input piece, and the torque transmission piece can rotate relative to the shell; the first detection object and the second detection object are arranged on the torque transmission piece and are separated by a preset distance in the axial direction of the torque transmission piece; the detection assembly is arranged on the shell and used for sensing a first detection object to obtain a first signal wave, the detection assembly is used for sensing a second detection object to obtain a second signal wave, the phase difference between the first signal wave and the second signal wave is used for determining the relative torsion angle between the detected cross section of the first detection object and the detected cross section of the second detection object, and the relative torsion angle is used for determining the torque transmitted on the torque transmission piece. The torque sensor is simple in structure and high in reliability.

Description

Torque sensor and electric power-assisted vehicle

Technical Field

The utility model relates to the technical field of mechanical equipment, in particular to a torque sensor and an electric power-assisted vehicle.

Background

The torque sensor is widely applied to products such as vehicles, aircrafts, mechanical devices and the like to detect torque. The existing torque sensor is usually a strain gauge sensor, and the strain gauge is attached to a rotating shaft (such as a middle shaft of an electric power-assisted bicycle) of a vehicle, an aircraft, a mechanical device and other products, and is deformed under the action of torsion by utilizing the principle that the rotating shaft deforms under the action of the torsion, so that the torque of the rotating shaft can be determined by measuring the deformation of the rotating shaft. However, this torque measurement method has the following problems. The strain gauge can work only by supplying power, so that the strain gauge attached to the rotating shaft needs to be wirelessly supplied with power, and meanwhile, a wireless transmission device is arranged on the rotating shaft to output deformation data detected by the strain gauge in a wireless transmission mode. This results in complex power supply and signal transmission for the torque sensor, higher manufacturing costs and lower operational reliability.

SUMMERY OF THE UTILITY MODEL

In view of the above problems, embodiments of the present invention are provided to provide a torque sensor and an electric assist vehicle that solve at least one of the problems described above.

One or more embodiments of the present invention provide a torque sensor including: a housing; the torque transmission piece is used for being connected with the torque input piece so as to transmit the torque input by the torque input piece, and the torque transmission piece can rotate relative to the shell; the first detection object and the second detection object are arranged on the torque transmission piece and are separated by a preset distance in the axial direction of the torque transmission piece; the detection assembly is arranged on the shell and used for sensing a first detection object to obtain a first signal wave, the detection assembly is used for sensing a second detection object to obtain a second signal wave, the phase difference between the first signal wave and the second signal wave is used for determining the relative torsion angle between the detected cross section of the first detection object and the detected cross section of the second detection object, and the relative torsion angle is used for determining the torque transmitted on the torque transmission piece.

Optionally, the torque sensor comprises a processing unit connected with the detection assembly to receive the first signal wave and the second signal wave output by the detection assembly and determine a relative torsion angle between the detected cross section of the first detection object and the detected cross section of the second detection object according to a phase difference between the first signal wave and the second signal wave.

Optionally, the processing unit is further configured to determine a rotational speed of the torque transmitting member based on at least one of the first signal wave and the second signal wave output by the detection assembly.

Optionally, the torque transmission part includes a first end section, a connecting section, and a second end section that are sequentially arranged in the axial direction, at least a part of the first detection object is disposed on the first end section, at least a part of the second detection object is disposed on the second end section, when the torque transmission part transmits torque and is torsionally deformed, a relative torsion angle between cross sections at two ends of the connecting section is a first angle, a relative torsion angle at two ends of the first end section is a second angle, a relative torsion angle at two ends of the second end section is a third angle, and the first angle is greater than at least one of the second angle and the third angle.

Optionally, the torque transmission member includes a first end section, a connecting section, and a second end section, which are sequentially arranged in the axial direction, the first detection object is disposed on at least a part of the first end section, the second detection object is disposed on at least a part of the second end section, and an elastic coefficient of the connecting section is lower than an elastic coefficient of at least one of the first end section and the second end section.

Optionally, the torque transmission member includes a first end section, a connecting section, and a second end section, which are sequentially arranged in the axial direction, the first detection object is disposed on at least a part of the first end section, the second detection object is disposed on at least a part of the second end section, and the length of the connecting section is greater than the length of at least one of the first end section and the second end section.

Optionally, the wall thickness of the connecting section is smaller than the wall thickness of the first end section and the second end section.

Optionally, the connecting section is provided with a first groove, so that the elastic coefficient of the connecting section is lower than the elastic coefficient of at least one of the first end section and the second end section.

Optionally, the detection assembly includes a photoelectric sensor, the first detection object and the second detection object each include a first reflection structure and a second reflection structure disposed alternately in a circumferential direction of the torque transmission member, and reflectances of the first reflection structure and the second reflection structure are different.

Optionally, the first reflective structure includes a stripe disposed on the circumferential surface of the torque transmission member and having a first reflectivity, and the second reflective structure includes a stripe disposed on the circumferential surface of the torque transmission member and having a second reflectivity, the first reflectivity is not equal to the second reflectivity.

Optionally, the first reflective structure comprises a plurality of protrusions, the plurality of protrusions being spaced apart in the circumferential direction of the torque transmitting member.

Optionally, the second reflecting structure includes a plurality of second grooves, and the second grooves are disposed between two adjacent protrusions.

Optionally, a plurality of first reflection structures are provided in the circumferential direction of the torque transmission member, and the plurality of first reflection structures are different in size in the circumferential direction of the torque transmission member.

Optionally, the detecting component includes an eddy current sensor, the first detecting object and the second detecting object each include a first magnetic conducting structure and a second magnetic conducting structure arranged at intervals along the circumferential direction of the torque transmission member, and a magnetic resistance formed between the first magnetic conducting structure and the detecting component is different from a magnetic resistance formed between the second magnetic conducting structure and the detecting component.

Optionally, the torque sensor further comprises an angle detector for detecting a rotation angle of the torque transmission member relative to the detection assembly at the cross section of the angle detector.

Optionally, the angle detector includes a magnetic ring and a hall sensor, the magnetic ring includes at least one pair of magnetic pole pairs arranged along the circumferential direction of the torque transmission member, the hall sensor is arranged in the housing to determine a rotation angle of the torque transmission member relative to the detection assembly at the cross section where the magnetic pole pair is located according to a third signal wave obtained by detecting the magnetic pole pair, and the rotation angle is used for determining an error compensation amount for the relative rotation angle.

Optionally, the first end of the torque transfer member is provided with an internal thread for mating with an external thread provided on the torque input member.

According to another aspect of the present invention, there is provided an electric power-assisted vehicle, comprising: a frame; the rotating shaft is rotatably arranged on the frame and is used for receiving external torque; the torque sensor comprises a torque transmission piece, a shell, a detection assembly, a first detection object and a second detection object, the shell is fixedly arranged on the frame, the torque transmission piece is sleeved outside the rotating shaft, the torque transmission piece comprises a first end and a second end, the first end is connected with the rotating shaft, so that the rotating shaft drives the torque transmission piece to rotate, the first detection object and the second detection object are arranged on the torque transmission piece, the detection assembly is used for detecting a first detection object to obtain a first signal wave, the detection assembly is used for detecting a second detection object to obtain a second signal wave, the phase difference between the first signal wave and the second signal wave is used for determining the relative torsion angle between the detected section of the first detection object and the detected section of the second detection object, and the relative torsion angle is used for determining the torque transmitted on the torque transmission piece; and the power output wheel is connected with the second end of the torque transmission piece so that the torque transmission piece drives the power output wheel to rotate.

Optionally, the electric power assisted vehicle further comprises a processing unit electrically connected with the detection assembly of the torque sensor to receive the first signal wave and the second signal wave output by the detection assembly and determine a relative torsion angle between the detected cross section of the first detection object and the detected cross section of the second detection object according to a phase difference between the first signal wave and the second signal wave.

Optionally, the torque transmission member includes a first end section, a connecting section, and a second end section, which are sequentially arranged in the axial direction, the first detection object and the second detection object are arranged on at least a part of the second end section, and the elastic coefficient of the connecting section is lower than the elastic coefficient of at least one of the first end section and the second end section.

Optionally, the first end of torque transmission spare is provided with the internal thread, is provided with the external screw thread on the pivot, and torque transmission spare passes through the internal thread and connects in the pivot with the external screw thread cooperation.

According to another aspect of the present invention, there is provided an electric power assisted vehicle including a frame; the rotating shaft is rotatably arranged on the frame; the torque sensor comprises a torque transmission piece, a detection assembly, a first detection object and a second detection object, wherein the torque transmission piece is sleeved outside a rotating shaft and comprises a first end and a second end, the first end is mechanically connected with the rotating shaft, the first detection object and the second detection object are arranged on the torque transmission piece and are separated from each other by a preset distance in the axial direction of the torque transmission piece, the detection assembly is fixedly arranged on a frame and is used for detecting the first detection object to obtain a first signal wave, the detection assembly is used for detecting the second detection object to obtain a second signal wave, the phase difference between the first signal wave and the second signal wave is used for determining the relative torsion angle between the detected section of the first detection object and the detected section of the second detection object, and the relative torsion angle is used for determining the torque transmitted on the torque transmission piece; and the power output wheel is connected with the second end of the torque transmission piece so that the torque transmission piece drives the power output wheel to rotate.

According to another aspect of the present invention, there is provided a torque sensor including: a housing; the rotating shaft can rotate relative to the shell; the torsion cylinder is connected with the rotating shaft to transmit the torque input by the rotating shaft; the first detection object and the second detection object are arranged on the torsion cylinder and are separated by a preset distance in the axial direction of the torsion cylinder; and the detection assembly is arranged on the shell and is static relative to the shell, the detection assembly is used for detecting a first detection object to generate a first signal wave, the detection assembly is used for detecting a second detection object to generate a second signal wave, the phase difference between the first signal wave and the second signal wave is used for determining the relative torsion angle between the detected section of the first detection object and the detected section of the second detection object, and the relative torsion angle is used for determining the torque transmitted by the torsion cylinder.

Optionally, the first end of the torque tube is provided with an internal thread, the rotating shaft is provided with an external thread, and the torque tube and the rotating shaft are connected through the internal thread and the external thread.

In one or more embodiments of the present invention, the torque detection is implemented by the detection component cooperating with the first detection object and the second detection object by providing the first detection object and the second detection object on the torque transmission member. Because the detection assembly is not arranged on the torque transmission piece but arranged on the shell, the detection assembly and the power supply structure of the detection assembly are relatively static, so that the detection assembly can be powered in a wired mode, and compared with a torque sensor using a wireless power supply structure, the torque sensor is simpler in structure, higher in reliability and lower in cost.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic cross-sectional structural view of a torque sensor provided in accordance with one or more embodiments of the present invention;

FIG. 2 is a schematic perspective view of a torque transmitting member of a torque sensor according to one or more embodiments of the present invention;

FIG. 3 is a schematic perspective view of a torque transmitting member of a torque sensor according to one or more embodiments of the present invention;

FIG. 4 is an enlarged view of a portion of FIG. 3 at A;

FIG. 5 is a schematic perspective view of a torque transmitting member of a torque sensor according to one or more embodiments of the present invention;

FIG. 6 is a schematic view of a second test object of the torque-transmitting member of FIG. 5;

FIG. 7 is an enlarged view of a portion of FIG. 6 at B;

FIG. 8 is a cross-sectional view of a torque transmitting member of a torque sensor according to one or more embodiments of the present invention;

FIG. 9 is a schematic illustration of a first signal wave and a second signal wave before deformation of a torque transmitting member according to one or more embodiments of the present invention;

FIG. 10 is a schematic illustration of a first signal wave and a second signal wave after deformation of a torque transmitting member according to one or more embodiments of the present invention; and

FIG. 11 is a schematic illustration of a first signal wave and a second signal wave before deformation of another torque transmitting member in accordance with one or more further embodiments of the utility model;

fig. 12 is a schematic perspective view of another deformed torque transmission member according to one or more embodiments of the present invention.

Detailed Description

In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in fig. 1 to 8, one or more embodiments of the present invention provide a torque sensor including a torque transmission member 10, a housing 50, a first detection object 31, a second detection object 32, and a detection assembly 40.

The torque transmission member 10 is used for connecting with the torque input member 20 to transmit the torque input by the torque input member 20, and the torque transmission member 10 can rotate relative to the shell 50; the first detection object 31 and the second detection object 32 are provided on the torque transmission member 10 and are separated by a predetermined distance in the axial direction of the torque transmission member 10; the detecting element 40 is disposed on the housing 50, the detecting element 40 is used for sensing the first detecting object 31 to obtain a first signal wave, and the detecting element 40 is used for sensing the second detecting object 32 to obtain a second signal wave. The phase difference between the first signal wave and the second signal wave is used to determine a relative torsion angle (difference between γ 1 and γ 2 as shown in fig. 12) between the detected cross section of the first detection object 31 and the detected cross section of the second detection object 32, and the relative torsion angle is used to determine the torque transmitted on the torque transmission member 10.

Since the first detection object 31 and the second detection object 32 are disposed on the torque transmission member 10 and the detection member 40 is disposed on the housing 50 such that the torque transmission member 10 is rotatable relative to the detection member 40, the first detection object 31 and the second detection object 32 are also rotatable relative to the detection member 40. Since the phase difference between the first signal wave and the second signal wave detected by the detecting unit 40 when the torque transmission member 10 is deformed by the torque (as shown in fig. 9) is different from the phase difference between the first signal wave and the second signal wave detected when the torque transmission member 10 is not deformed (as shown in fig. 10), the relative torsion angle between the detected cross section of the first detection object 31 and the detected cross section of the second detection object 32 can be calculated based on the detected phase difference between the first signal wave and the second signal wave, and the torque transmitted to the torque transmission member 10 can be calculated.

In the way of providing the first detection object 31 and the second detection object 32 on the torque transmission member 10 and detecting the torque by using the detection assembly 40 in cooperation with the first detection object 31 and the second detection object 32, the detection assembly 40 is not provided on the rotating torque transmission member 10 but on the housing 50, so that the detection assembly 40 and the power supply structure thereof can be relatively stationary, which enables wired power supply to the detection assembly 40, and compared with a torque sensor using a wireless power supply structure, the torque sensor is simpler in structure, higher in reliability and lower in cost.

The structure and operation of the torque sensor will be described in detail below with reference to the accompanying drawings:

as shown in fig. 1, in the present embodiment, a vehicle to which the torque sensor is applied is taken as an example of an electric power assisted bicycle. The electric power-assisted bicycle takes a battery as an auxiliary power source, and is a novel vehicle for realizing integration of manual riding and motor power assistance. The torque sensor is a core component for understanding the intention of a rider of the electric power-assisted system of the power-assisted bicycle, and the output power of the motor of the electric bicycle can be adjusted according to the measured torque in the riding process due to the existence of the torque sensor, so that the riding comfort is improved. When the torque transmission member 10 is applied to an electric power assisted bicycle, the torque input member 20 may be a rotating shaft (also called a bottom bracket) of the electric power assisted bicycle, and both ends of the rotating shaft may be used as power input ends to connect pedals. The user (or rider) inputs power through the pedal. Of course, in other embodiments, the torque sensor may be applied to other electric vehicles, fuel vehicles, etc., or other suitable devices, without limitation.

In the present embodiment, the torque transmission member 10 includes a first end and a second end, the first end is fixedly connected to the torque input member 20, the second end is connected to the torque output member 70, and the torque input member 20 does not directly output the torque to the second end, so as to ensure that the torque input from any position of the torque input member 20 needs to be transmitted to the torque output member 70 through the torque transmission member 10, so that the torque input by the torque input member 20 can be determined only by detecting the torque on the torque transmission member 10. In the embodiment, the torque detection can be realized by one torque sensor, so that the space occupied by the torque sensor can be reduced, the cost is reduced, and the reliability is improved.

The fixed connection between the torque transmitting member 10 and the torque input member 20 may be a spline connection or a welded connection, and the like, but is not limited thereto.

Preferably, the first end of the torque transmission member 10 is provided with an internal thread for cooperating with an external thread provided on the torque input member 20 to achieve a fixed connection of the torque transmission member 10 and the torque input member 20. The threaded connection mode is low in cost and high in reliability, and overcomes the technical prejudice that the transmission cannot be carried out by threaded connection between the middle shaft and the barrel in the prior art. When the torque sensor is applied to an electrically assisted vehicle, the torque output member includes a turning device of a rear wheel. The rotating device is provided with a ratchet wheel (also called a jack). When the torque input member 20 is stepped in the first rotational direction, the torque input member 20 transmits the torque to the rotating device through the torque transmitting member, and the vehicle moves forward. When the torque input member 20 is stepped on in the second rotational direction, the torque input member 20 rotates in a reverse direction, the torque is transmitted to the ratchet wheel, and the ratchet wheel idles and is not transmitted to the wheel, that is, when the torque input member 20 is stepped on in the second rotational direction (i.e., when the foot is stepped on in a reverse direction), the torque sensor may not output the torque.

When the torque input member 20 is stepped in the second rotation direction, the torque transmitted by the torque transmission member 10 is almost negligible because the ratchet wheel idles, and the torque transmitted by the torque transmission member 10 is smaller than the self-locking force (friction force) between the internal thread and the external thread, so that the torque input member 20 and the torque transmission member 10 which are connected by the threads are not loosened.

Compared with spline connection, the torque transmission part 10 and the torque input part 20 are in threaded connection, extra parts are not needed, the structure is simple, the processing and the installation are convenient, and the assembling efficiency can be improved.

The first rotation direction is opposite to the second rotation direction, and under the same visual angle, if the first rotation direction is clockwise, the second rotation direction is counterclockwise.

In an electric power-assisted vehicle (such as an electric power-assisted bicycle), the torque input part 20 and the torque transmission part 10 can be matched through the internal thread and the external thread, the screwing directions of the internal thread and the external thread are screwing directions (for example, the screwing directions of the internal thread and the external thread are the first screwing directions under the same visual angle), and when the torque input part 20 rotates along the screwing direction (the electric power-assisted bicycle is in a forward state), the connection between the torque input part 20 and the torque transmission part 10 is firmer, so that the reliability is ensured. Different types of detection assemblies 40 can be used to detect the first detection object 31 and the second detection object 32 according to different requirements. For example, the detection unit 40 may be a non-contact sensor such as a photoelectric sensor, an eddy current sensor, or a distance sensor, or may be a contact sensor such as a brush or an electrical slip ring.

The first detection object 31 and the second detection object 32 are separated by a preset distance in the axial direction of the torque transmission member 10, so that the detected phase difference can be ensured to be obvious, and the detection accuracy can be further improved. In order to ensure the accuracy of the detection, in one or more embodiments of the present invention, the number of the detection assemblies 40 may be 2, and the 2 detection assemblies 40 may be respectively disposed corresponding to the first detection object 31 and the second detection object 32. Of course, in other embodiments, the detection assembly 40 may have an integral structure (as long as it can sense the first detection object 31 and the second detection object 32), or more than 2, as long as it can ensure the detection accuracy.

The first detection object 31 and the second detection object 32 may adopt a structure adapted thereto for different types of detection members 40.

For example, when the sensing assembly 40 includes an eddy current sensor, the first and second sensing objects 31 and 32 each include a magnetically conductive structure including first and second magnetically conductive structures disposed at intervals along a circumferential direction of the torque transmitting member 10, and a magnetic resistance formed between the first magnetically conductive structure and the sensing assembly 40 is different from a magnetic resistance formed between the second magnetically conductive structure and the sensing assembly 40.

In one example, the magnetically permeable structure may be a gear, and since the teeth of the gear are typically made of a metal material and the space between two adjacent teeth is typically air, the magnetic resistance formed between the metal material and the air and the detecting assembly 40 is different. For convenience of description, when the tooth portion of the gear is rotated to a position corresponding to the detecting element 40, the electric signal output by the detecting element 40 is referred to as signal 1, and when the gap is rotated to a position corresponding to the detecting element 40, the electric signal output by the detecting element is referred to as signal 2, and since the magnetic resistance formed between the tooth portion (in the present embodiment, the first magnetic conductive structure) and the detecting element 40 is smaller than the magnetic resistance formed between the gap (in the present embodiment, the second magnetic conductive structure) and the detecting element 40, the signal 1 and the signal 2 are different, and thus the first signal wave is formed. Similarly, the second signal wave can be obtained, and therefore, the description is omitted.

For another example, in one or more examples of the present application, as shown in fig. 2, when the detection assembly 40 includes a photosensor, each of the first detection object 31 and the second detection object 32 includes a reflection portion including

first reflection structures

311 and 321 and

second reflection structures

312 and 322 disposed at intervals in a circumferential direction of the torque transmission member 10, and reflectances of the

first reflection structures

311 and 321 and the

second reflection structures

312 and 322 are different.

Thus, during the rotation of the torque transmission member 10, the

first reflection structures

311 and 321 and the

second reflection structures

312 and 322 alternately move to the positions corresponding to the photosensors, and the light intensities of the light reflected by the

first reflection structures

311 and 321 and the light reflected by the

second reflection structures

312 and 322 are different, so that the electric potential of the electrical signal output by the photosensors changes, and the first signal wave and the second signal wave are formed. Since the first detection object 31 and the second detection object 32 are separated by a predetermined distance in the axial direction of the torque transmission member 10, the relative position between the two changes with the deformation of the torque transmission member 10, which results in a change in the phase difference between the first signal wave and the second signal wave, and the relative torsion angle between the detected cross section of the first detection object 31 (cross section 1 in fig. 12, which corresponds to the first photoelectric sensor) and the detected cross section of the second detection object 32 (cross section 2 in fig. 12, which corresponds to the second photoelectric sensor) can be determined according to the change in the phase difference, and the torque can be determined according to the relative torsion angle.

In the example shown in fig. 2, the first

reflective structures

311 and 321 include stripes having a first reflectivity disposed on the circumferential surface of the torque transmission member 10, and the second

reflective structures

312 and 322 include stripes having a second reflectivity disposed on the circumferential surface of the torque transmission member 10, wherein the first reflectivity is not equal to the second reflectivity. The stripe has simple structure, convenient processing and high reliability. The present embodiment does not limit the number of the stripes of the first reflectance and the stripes of the second reflectance, and the number of the stripes of the first reflectance and the stripes of the second reflectance may be determined, for example, at least one, according to the required torque detection frequency.

In this example, the stripe is described, but the shape is not limited thereto, and the stripe may be any region having a different reflectance. For example, the stripes having the first reflectivity may be formed by laser machining on the circumferential surface of the torque transmission member 10, while the portions not being laser naturally form the stripes having the second reflectivity.

In addition to the laser method, the stripes of the first reflectance may be formed by coating the circumferential surface of the torque transmission element 10 with the material layer at intervals, the stripe of the second reflectance may be formed between two adjacent stripes of the first reflectance, or another material layer of the second reflectance may be coated between two adjacent stripes of the first reflectance.

Alternatively, the first

reflective structures

311 and 321 and the second

reflective structures

312 and 322 may be formed by attaching a coating having different reflectances to the circumferential surface of the torque transmission member 10, which is not illustrated.

The first reflectance and the second reflectance are not limited to the same numerical value as long as they are different.

The first

reflective structures

311 and 321 and the second

reflective structures

312 and 322 may be stripes, but may also be other structures, for example, in another example shown in fig. 5, the first

reflective structures

311 and 321 are a plurality of protrusions, and the plurality of protrusions are spaced apart in the circumferential direction of the torque transmission member 10. The second

reflective structures

312 and 322 include a plurality of second grooves disposed between two adjacent protrusions. The second recess may be a naturally formed gap between two adjacent projections, or may be a combination of a gap and a recess provided in the torque transmitting member 10.

In one possible way, the reflectivity of the gap formed between two adjacent bumps is different from the reflectivity of the bump, so that the signal output by the photosensor changes. When the protrusion rotates to a position corresponding to the photoelectric sensor in the rotation process of the torque transmission member 10, because the top surface of the protrusion faces the photoelectric sensor, most of light irradiated on the top surface is reflected back to the photoelectric sensor, so that the light intensity received by the photoelectric sensor is stronger; when the gap between two adjacent bulges rotates to the position corresponding to the photoelectric sensor, light irradiates the side wall of the bulge and most of the light is reflected to the bottom of the gap, so that the light intensity received by the photoelectric sensor is weaker, and the electric signal output by the photoelectric sensor changes.

Of course, in other embodiments, the light intensity reflected by the void may be made stronger than the light intensity reflected by the top surface of the protrusion in other ways, which may also effect signal changes.

Preferably, as shown in fig. 6, the shape of the sidewall of the protrusion or the depth and width of the formed gap are adjusted, so that the difference of the reflectivity of the gap and the protrusion to light is significant, thereby improving the identifiability of detection.

When the width and the depth of the gap are adjusted, the adjustment may be performed by adjusting the height of the protrusions and the distance between the protrusions, or may be performed by forming a groove in the torque transmission member 10 at a position corresponding to the gap, which is not limited thereto.

Of course, if the detecting component 40 includes a distance sensor, the distance sensor may also obtain the first signal wave and the second signal wave by detecting different distances between the top surface of the protrusion and the bottom surface of the gap and the distance sensor, which is not described herein again.

The process of determining the torque based on the first signal wave and the second signal wave is described below with reference to the accompanying drawings: fig. 9 shows a schematic diagram of a first signal wave (upper signal in fig. 9) obtained by the photoelectric sensor detecting the first detection object 31 and a second signal wave (lower signal in fig. 9) obtained by the photoelectric sensor detecting the second detection object 32 when the torque transmitting member 10 is not deformed.

The first detection object 31 includes a plurality of

first reflection structures

311 and 321 and a plurality of

second reflection structures

312 and 322 provided in the circumferential direction of the torque transmission member 10. Similarly, the second detection object 32 also includes a plurality of

first reflection structures

311 and 321 and a plurality of

second reflection structures

312 and 322, and the

first reflection structures

311 and 321 in the first detection object 31 may be in one-to-one correspondence with the

first reflection structures

311 and 321 in the second detection object 32 on the circumference (there may be a slight machining error, which is ignored here), that is, when the torque transmission member 10 is not deformed, the phase difference between the first signal wave and the second signal wave may be approximately 0.

As shown in fig. 10, when the torque transmission member 10 is deformed, a misalignment occurs between the

first reflection structures

311, 321 in the first detection object 31 and the corresponding

first reflection structures

311, 321 in the second detection object 32 due to the torsion thereof, and a phase difference between a first signal wave (upper signal in fig. 10) obtained by the photosensor detecting the first detection object 31 and a second signal wave (lower signal in fig. 10) obtained by the photosensor detecting the second detection object 32 changes during the rotation of the torque transmission member 10. The phase difference between the first signal wave and the second signal wave in the example shown in fig. 10 is β.

The process of determining the torque based on the phase difference of the first signal wave and the second signal wave is as follows:

if the dimensions H (as shown in fig. 7) of the plurality of first reflecting

structures

311 and 321 in the circumferential direction of the torque transmission member 10 are the same, the angular velocity ω (ω ═ α/t) at which the torque transmission member 10 rotates can be determined from the central angle α of the first reflecting structures 311 and 321 (which can be determined during machining) and the time t required for the first reflecting

structures

311 and 321 to rotate past the detection unit 40 (which is determined from the first signal wave or the second signal wave).

The deviation angle between the two first reflecting

structures

311, 321 can be determined according to the angular velocity ω of the rotation of the torque transmission element 10 and the time difference t β corresponding to the phase difference β between the first signal wave and the second signal wave

The deviation angle is a relative torsion angle between the detected cross section of the first detection object 31 and the detected cross section of the second detection object 32 when the torque transmission member 10 is deformed by the torque.

Since the deviation angle between the two corresponding first

reflective structures

311, 321 before the torque transmission member 10 is deformed is 0, the total deviation angle after deformation is the deviation angle after deformation

And therefore according to the elastic coefficient k (determined based on material, shape, thickness, etc., which can be measured) and deviation angle of the torque transmission member 10

The torque can be determined

Preferably, in order to reduce the error, the corresponding relationship between the deviation angle and the torque may be calibrated in advance, and the torque corresponding to the deviation angle may be determined according to the calibrated corresponding relationship after the deviation angle is calculated. Therefore, the problem that the calculated torque is inaccurate due to the fact that the elastic coefficient of the torque transmission part 10 is inaccurate or the elastic coefficients of different positions are different can be solved.

Preferably, in order to ensure the accuracy of the torque determination, the

first reflection structures

311 and 321 corresponding to each peak of the first signal wave and the second signal wave may be determined, and the

second reflection structures

312 and 322 corresponding to each valley may be determined, for this reason, the torque sensor may further include an angle detector for detecting a rotation angle of the torque transmission member 10 relative to the detection assembly 40 at a cross section where the angle detector is located. Of course, in other embodiments, the peaks may correspond to the second reflective structure and the valleys to the first reflective structure.

Returning to fig. 1, in one or more examples of the present invention, the angle detector includes a magnetic ring 61 and a hall sensor 62, the magnetic ring 61 includes at least one pair of magnetic pole pairs disposed along a circumferential direction of the torque transmission member 10, the hall sensor 62 is disposed on the housing 50 to determine a rotation angle of the torque transmission member 10 relative to the detection assembly 40 at a cross section where the magnetic pole pair is located according to a third signal wave obtained by detecting the magnetic pole pair, and the rotation angle is used for determining an error compensation amount for the relative rotation angle. The potential output by the hall sensor 62 is changed by the rotation of the magnetic ring 61 to form a third signal wave, the rotation angle of the torque transmission member 10 can be determined based on the third signal wave, and then the reflection structure corresponding to the detection assembly at the current moment can be determined according to the rotation angle and the relative position relationship between the magnetic ring 61 and the

first reflection structures

311, 321 and the

second reflection structures

312, 322. Thus, even if there is some error in the size of the plurality of first reflecting

structures

311, 321 in the circumferential direction of the torque transmission member 10, error compensation can be performed, thereby improving the accuracy of the torque.

Because the hall sensor 62 is arranged on the shell 50, the hall sensor 62 which needs to be powered can be fixed relative to the power supply structure, thereby realizing wired power supply, improving the reliability and reducing the cost of the torque sensor.

In another example, the first detection object 31 and the second detection object 32 may also perform rotation angle detection as absolute angle sensing components, and in order to achieve this function, when the plurality of

first reflection structures

311 and 321 are provided in the circumferential direction of the torque transmission member 10, the sizes H of the plurality of first reflection structures in the circumferential direction of the torque transmission member 10 are different. Thus, the corresponding first reflecting

structure

311, 321 can be determined according to the time length of each peak or trough in the first signal wave or the second signal wave, so that the rotation angle can be determined.

Further, the second reflecting

structures

312 and 322 between two adjacent first reflecting

structures

311 and 321 may have the same size in the circumferential direction of the torque transmission member 10 (which may have machining errors and is ignored here), so as to obtain the first signal wave and the second signal wave as shown in fig. 11, and the corresponding first reflecting

structure

311 and 321 may also be determined according to the ratio of the time length of the peak to the previous valley in the first signal wave or the second signal wave, so that the rotation angle may be determined.

It should be noted that the determination of the torque transmission member 10 according to the obtained phase difference between the first signal wave and the second signal wave can be realized by the detection component 40, and can also be realized by an external processing unit. In addition to this, the torque sensor can also detect the rotational speed of the torque transmission element 10. The processing unit may be a CPU (central processing unit), an AFCP circuit, or an MCU, etc., as long as the data processing requirements can be satisfied.

Taking the external processing unit as an example, the processing unit is connected to the detecting assembly 40 to receive the first signal wave and the second signal wave output by the detecting assembly 40, and determine the relative torsion angle between the detected cross section of the first detected object 31 and the detected cross section of the second detected object 32 according to the phase difference between the first signal wave and the second signal wave.

Of course, the processing unit may also receive the third signal wave, and determine the rotation angle based on the third signal wave.

The processing unit and sensing assembly 40 may be wired to transmit electrical signals, or may transmit electrical signals via a wireless connection.

In addition to this, the processing unit can also determine the rotational speed of the torque transmission element 10 from at least one of the first signal wave and the second signal wave.

For example, the angular velocity may be determined according to the time length corresponding to a peak in the first signal wave and the central angle of the first reflecting structure or the second reflecting structure corresponding to the peak, and then the rotation speed may be determined according to the angular velocity.

As described above, since the farther the distance between the first detection object 31 and the second detection object 32 in the axial direction is, the larger the relative torsion angle between the detected cross section of the first detection object 31 and the detected cross section of the second detection object 32 is, the larger the phase difference between the first signal wave and the second signal wave is, and the larger the phase difference can improve the accuracy of torque detection.

For this reason, in this embodiment, the torque transmission member 10 includes the first end section 11, the connecting section 12 and the second end section 13 that set gradually in the axial direction, the first detection object 31 is disposed in at least some first end sections 11, the second detection object 32 is disposed in at least some second end sections 13, when the torque transmission member 10 transmits the torque and the torsional deformation, the relative torsion angle between the cross-sections at both ends of the connecting section 12 is the first angle, the relative torsion angle at both ends of the first end section 11 is the second angle, the relative torsion angle at both ends of the second end section 13 is the third angle, the first angle is greater than at least one of the second angle and the third angle. This makes it possible to increase the relative twist angle as much as possible, thereby making the phase difference more noticeable.

Preferably, the second angle and the third angle are equal, or the difference between the two angles is smaller than a set threshold (the set threshold can be determined as required, but is not limited thereto), so that the deformation amount at the first detection object 31 and the deformation amount at the second detection object 32 can be ensured to be consistent as much as possible, and the measurement accuracy is higher.

It should be noted that although the first detection object 31 and the second detection object 32 are described as two independent detection objects in this embodiment, the present invention is not limited thereto, and in other embodiments, the first detection object 31 and the second detection object 32 may be integrally configured.

In addition, since the size (corresponding to the central angle) of the first

reflective structures

311, 321 and the second

reflective structures

312, 322 in the circumferential direction of the torque transmission member 10 is required when calculating the torque, the more accurate the size is, the more accurate the calculated torque is, when the torque transmission member 10 is deformed, the first

reflective structures

311, 321 and the second

reflective structures

312, 322 may also be deformed to some extent, which causes the size in the circumferential direction and the size when the torque transmission member is not deformed to be changed, and in order to reduce the change, the elastic coefficient of the connection section 12 of the torque transmission member 10 may be lower than the elastic coefficient of at least one of the first end section 11 and the second end section 13, so that the change of the central angles of the first

reflective structures

311, 321 and the second

reflective structures

312, 322 may be reduced as much as possible, thereby improving the accuracy of the torque calculation.

In addition to this, the torque transmission member 10 can increase the relative torsion angle between the detected cross section of the first detection object 31 and the detected cross section of the second detection object 32, thereby making the phase difference between the first signal wave and the second signal wave more noticeable.

Preferably, in the present embodiment, the elastic coefficient of the connecting section 12 is smaller than the elastic coefficients of the first end section 11 and the second end section 13. While the lower spring constant of the connecting section 12 may be achieved by using a different material treatment for the connecting section 12 than for the first end section 11 and the second end section 13.

Alternatively, the wall thickness of the connecting section 12 is smaller than the wall thickness of at least one of the first end section 11 and the second end section 13. The spring constant of the different segments can also be made different by varying the wall thickness. As shown in fig. 8, by providing a groove in the outer periphery of the connecting section 12, the wall thickness of the connecting section 12 is reduced, thereby reducing its elastic coefficient. Alternatively, the wall thickness of the connecting section 12 is made smaller by providing a groove (not shown) in the inner wall of the connecting section 12, thereby reducing its elastic modulus. Of course, the two methods may be used in combination.

Still alternatively, as shown in fig. 3 to 5, the connection segment 12 is provided with a first groove 121 for reducing the elastic coefficient of the connection segment 12. The first recess may or may not extend through the connecting section 12 in the wall thickness direction.

Preferably, the extending direction of the first groove 121 may coincide with the twisting direction of the torque transmitting member 10, thereby making it easier to be deformed.

It should be noted that the aforementioned first end section 11, the connecting section 12 and the second end section 13 may be integrally formed, and the 3 sections are logically segmented based on the difference of the elastic coefficients.

In addition to adjusting the elastic modulus of the different segments, the relative torsion angle of the cross-sections at the two ends of the connecting segment 12 can also be made larger by adjusting the axial lengths of the different segments.

For example, the length of the connecting section 12 is greater than the length of at least one of the first end section 11 and the second end section 13, so that the relative torsion angle between the detected cross section of the first detection object 31 and the detected cross section of the second detection object 32 can be increased due to the long length of the torque transmission member 10 in the axial direction, and the phase difference between the first signal wave and the second signal wave is significant.

To sum up, set up first detection object and second detection object on torque transmission piece 10 of torque sensor and need not power supply and signal transmission, avoid the part that needs electric power to rotate along with torque transmission piece 10 and need wireless power supply, lead to with high costs, the low problem of reliability, detection component 40 that needs the power supply can be static relatively with the power supply structure to need not wireless power supply and wireless signal transmission, both saved the cost, promoted the reliability again.

According to another aspect of the present invention, there is provided a torque sensor including a housing, a rotation shaft, a torque cylinder, a detection assembly, a first detection object, and a second detection object. Wherein, the rotating shaft can rotate relative to the shell; the torque barrel (which is equivalent to the torque transmission member in the previous embodiment) is used for connecting with the rotating shaft to transmit the torque input by the rotating shaft; the first detection object and the second detection object are arranged on the torsion cylinder and are separated by a preset distance in the axial direction of the torsion cylinder (both the preset distance and the preset distance can be determined according to requirements); the detection assembly is arranged on the shell and is static relative to the shell, the detection assembly is used for detecting a first detection object to generate a first signal wave, the detection assembly is used for detecting a second detection object to generate a second signal wave, the phase difference between the first signal wave and the second signal wave is used for determining the relative torsion angle between the detected section of the first detection object 31 and the detected section of the second detection object 32, and the relative torsion angle is used for determining the torque transmitted by the torsion cylinder.

In this embodiment, the first end of a torsion section of thick bamboo is provided with the internal thread, is provided with the external screw thread in the pivot, and a torsion section of thick bamboo and pivot pass through internal thread and external screw thread connection, can reduction in production cost like this, and make processing, production more convenient. The advantages and principles of the threaded connection have been fully explained in the previous example of the torque sensor and will not be described in further detail.

The detection process of the detection assembly may be similar to the detection process of the detection assembly 40 of the torque sensor, and thus, the description thereof is omitted. It should be noted that, in other embodiments, the first detection object and the second detection object may be disposed on the rotating shaft or other structures requiring torque detection as required.

Another aspect of the present invention provides an electric power assisted vehicle. The electric power-assisted vehicle comprises a frame, a rotating shaft, a torque sensor and a power output wheel. The rotating shaft is rotatably arranged on the frame and is used for receiving external torque; the torque sensor comprises a torque transmission part 10, a shell 50, a detection component 40, a first detection object 31 and a second detection object 32, wherein the shell 50 is fixedly arranged on the frame, the torque transmission part 10 is sleeved outside a rotating shaft, the torque transmission part 10 comprises a first end and a second end, the first end is connected with the rotating shaft, so that the rotating shaft drives the torque transmission member 10 to rotate, the first detection object 31 and the second detection object 32 are disposed on the torque transmission member 10, and the detecting assembly 40 is used for detecting the first detection object 31 to obtain a first signal wave, the detecting assembly 40 is used for detecting the second detection object 32 to obtain a second signal wave, the phase difference between the first signal wave and the second signal wave is used for determining the relative torsion angle between the detected cross section of the first detection object 31 and the detected cross section of the second detection object 32, and the relative torsion angle is used for determining the torque transmitted on the torque transmission member 10. The power take-off wheel is connected to the second end of the torque transmission member 10 so that the torque transmission member 10 rotates the power take-off wheel.

In the embodiment, the electric power-assisted vehicle comprises a power-assisted motor, and a part of torque is provided for the running of the vehicle through the power-assisted motor, so that power assistance is realized. Such as an electric assist bicycle, which moves torque in part from the torque applied by the rider and in part from the torque output by the assist motor.

In the electric power-assisted vehicle, a rotating shaft serves as the torque input member 20, and a power output shaft, which may be a sprocket or a gear set, etc., serves as the torque output member 70. Taking a sprocket as an example, the torque sensor is provided in an electric power-assisted vehicle, and the torque sensor can detect the torque output to the sprocket, and since the housing 50 of the torque sensor is fixedly provided to the vehicle frame and the electric components such as the detection unit 40 and the detection signal output unit are provided to the housing 50, these electric components are stationary with respect to the vehicle frame and are stationary with respect to the power supply structure such as a power supply mounted to the vehicle frame, and thus the torque sensor can be supplied with power by wire, and reliability can be improved.

Optionally, the electric power assisted vehicle further comprises a processing unit electrically connected with the detection assembly 40 of the torque sensor to receive the first signal wave and the second signal wave output by the detection assembly 40 and determine a relative torsion angle between the detected cross section of the first detection object 31 and the detected cross section of the second detection object 32 according to a phase difference between the first signal wave and the second signal wave.

The processing unit is further configured to determine a rotational speed of the torque transmitting member 10 based on at least one of the first signal wave and the second signal wave output by the sensing assembly 40.

For example, the rotational speed may be calculated based on the aforementioned calculated angular velocity. Therefore, a rotating speed sensor is not required to be additionally arranged, the torque and the rotating speed are detected through the torque sensor, the cost is saved, and the occupied space is reduced.

In addition, the torque sensor can ensure that the torque measured when the torque transmission piece 10 does not rotate is 0 in principle according to the angular speed of the rotation of the torque transmission piece 10 when measuring the torque, so that the torque is not output when the speed of 0 is ensured, and therefore, the processing unit can not output a control signal of the torque to the power-assisted motor of the electric power-assisted vehicle, so that the safety is ensured. And the tread frequency can be naturally obtained in the process of measuring based on the phase difference, so that a special detection speed sensor can be omitted, the structure is simple, and the cost is low.

In the present embodiment, the torque sensor may have the same or similar structure as the torque sensor in the foregoing embodiments to achieve the same or similar effects. Therefore, the structure and effects of the torque sensor in the present embodiment will be briefly described as follows:

the torque transmission member 10 includes a first end and a second end, the first end is fixedly connected to the torque input member 20, the second end is connected to the torque output member 70, and the torque input member 20 does not directly transmit the torque to the second end, so as to ensure that the torque input from any position of the torque input member 20 needs to be transmitted to the torque output member 70 through the torque transmission member 10, and thus the torque input by the torque input member 20 can be determined only by detecting the torque on the torque transmission member 10. In the embodiment, the torque detection can be realized by one torque sensor, so that the space occupied by the torque sensor can be reduced, the cost is reduced, and the reliability is improved.

Preferably, the first end of the torque transfer member 10 is provided with an internal thread for mating with an external thread provided on the torque input member to achieve a fixed connection of the torque transfer member 10 and the torque input member 20. The screw connection is only low in cost and high in reliability, and the principle of the screw connection is fully explained in the example of the torque sensor, so that the details are not repeated. The use of threaded connections in the electric power assisted vehicle scenario, which does not require torque output when the shaft is rotating in the opposite direction, can reduce costs and processing difficulties.

By detecting the torque on the torque transmitting member 10, the user's intention can be judged based on the torque, and a corresponding response can be made. For example, detecting an increase in torque at the torque transmitting element 10 indicates that the user wishes to accelerate, and the assist motor of the electric assist vehicle can be controlled to output a greater torque, thereby increasing the speed of travel of the electric assist vehicle. Or, the detected torque is used as an output signal to provide a feedback signal for the power-assisted motor, so that the power-assisted motor provides a driving force with preset times according to the torque input by the torque input member 20, and the electric power-assisted vehicle is driven more laborsavingly or at a higher speed, thereby meeting the use requirement.

Different types of detection assemblies 40 can be used to detect the first detection object 31 and the second detection object 32 according to different requirements. For example, the detection unit 40 may be a non-contact sensor such as a photoelectric sensor, an eddy current sensor, or a distance sensor, or may be a contact sensor such as a brush or an electrical slip ring.

The first detection object 31 and the second detection object 32 are separated by a preset distance in the axial direction of the torque transmission member 10. In order to ensure the accuracy of the detection, in one or more embodiments of the present invention, the number of the detection assemblies 40 may be 2, and the 2 detection assemblies 40 may be respectively disposed corresponding to the first detection object 31 and the second detection object 32. Of course, in other embodiments, the detection assembly 40 may have an integral structure (as long as it can sense the first detection object 31 and the second detection object 32), or more than 2, as long as it can ensure the detection accuracy.

For another example, in one or more examples of the present invention, as shown in fig. 2, when the detection assembly 40 includes a photosensor, each of the first detection object 31 and the second detection object 32 includes a reflection portion including

first reflection structures

311, 321 and

second reflection structures

312, 322 disposed at intervals in a circumferential direction of the torque transmission member 10, and the

first reflection structures

311, 321 and the

second reflection structures

312, 322 have different reflectivities.

Thus, during the rotation of the torque transmission member 10, the

first reflection structures

311 and 321 and the

second reflection structures

first reflection structures

311 and 321 and the light reflected by the

second reflection structures

312 and 322 are different, so that the electric potential of the electrical signal output by the photosensors changes, and the first signal wave and the second signal wave are formed. Since the first detection object 31 and the second detection object 32 are separated by a predetermined distance in the axial direction of the torque transmission member 10, the relative position between the two changes with the deformation of the torque transmission member 10, which results in a change in the phase difference between the first signal wave and the second signal wave, and the relative torsion angle between the detected cross section (cross section 1 in fig. 12) of the first detection object 31 and the detected cross section (cross section 2 in fig. 12) of the second detection object 32 can be determined according to the change in the phase difference, and the torque can be determined according to the relative torsion angle.

In the example shown in fig. 2, the first

reflective structures

312 and 322 include stripes having a second reflectivity disposed on the circumferential surface of the torque transmission member 10, wherein the first reflectivity is not equal to the second reflectivity. The stripe has simple structure, convenient processing and high reliability. The present embodiment does not limit the number of the stripes of the first reflectance and the stripes of the second reflectance that are provided. The number of stripes of the first reflectivity and the stripes of the second reflectivity may be determined, for example, at least one, according to the frequency of torque detection required.

Alternatively, the first

reflective structures

311 and 321 and the second

reflective structures

The first

reflective structures

311 and 321 and the second

reflective structures

The first detection object 31 includes a plurality of

first reflection structures

311 and 321 and a plurality of

second reflection structures

first reflection structures

311 and 321 and a plurality of

second reflection structures

312 and 322, and the

first reflection structures

311, 321 in the first detection object 31 and the corresponding

first reflection structures

if the dimensions H (as shown in fig. 7) of the plurality of first reflecting

structures

A deviation angle Φ (Φ ═ ω × t β) between the two corresponding

first reflection structures

311, 321, which is a relative torsion angle between the detected cross section of the first detection object 31 and the detected cross section of the second detection object 32 when the torque transmission member 10 is deformed by the torque, can be determined from the angular velocity ω at which the torque transmission member 10 rotates and the time difference (denoted as t β) corresponding to the phase difference β between the first signal wave and the second signal wave.

Since the deviation angle between the two corresponding first

reflective structures

311, 321 before the torque transmission member 10 is deformed is 0, the total deviation angle after deformation is Φ, and the torque T (T ═ Φ × k) can be determined according to the elastic modulus k (determined based on the material, shape, thickness, etc., which can be measured) of the torque transmission member 10 and the deviation angle Φ.

Preferably, in order to ensure the accuracy of the torque determination, the

first reflection structures

second reflection structures

In one or more examples of the present invention, the angle detector includes a magnetic ring 61 and a hall sensor 62, the magnetic ring 61 includes at least one pair of magnetic pole pairs disposed along a circumferential direction of the torque transmission member 10, the hall sensor 62 is disposed on the housing 50 to determine a rotation angle of the torque transmission member 10 relative to the detection assembly 40 at a cross section where the magnetic pole pair is located according to a third signal wave obtained by detecting the magnetic pole pair, and the rotation angle is used for determining an error compensation amount for the relative rotation angle. The potential output by the hall sensor 62 is changed by the rotation of the magnetic ring 61 to form a third signal wave, the rotation angle of the torque transmission member 10 can be determined based on the third signal wave, and then the reflection structure corresponding to the detection assembly at the current moment can be determined according to the rotation angle and the relative position relationship between the magnetic ring 61 and the

first reflection structures

311, 321 and the

second reflection structures

structures

first reflection structures

structure

Further, the second reflecting

structures

312 and 322 between two adjacent first reflecting

structures

structure

Preferably, the second angle and the third angle are equal, or the difference between the two angles is smaller than or equal to a set threshold (the set threshold can be determined as required, but is not limited thereto), so that the deformation amount at the first detection object 31 and the deformation amount at the second detection object 32 can be ensured to be consistent as much as possible, thereby enabling the measurement accuracy to be higher.

In addition, since the size of the first reflecting

structures

311, 321 and the second reflecting

structures

312, 322 in the circumferential direction of the torque transmission member 10 is required when calculating the torque, the more accurate the size is, the more accurate the calculated torque is, when the torque transmission member 10 deforms, the first reflecting

structures

311, 321 and the second reflecting

structures

312, 322 may also deform to some extent, which causes the size in the circumferential direction and the size when the torque transmission member is not deformed to change, and in order to reduce the change as much as possible, the elastic coefficient of the connecting section 12 of the torque transmission member 10 may be lower than the elastic coefficient of at least one of the first end section 11 and the second end section 13, so that the change of the central angles of the first reflecting

structures

311, 321 and the second reflecting

structures

In summary, the torque transmission member 10 of the torque sensor (the electrical components such as the detection component 40 and the hall sensor 62) is disposed on the housing, so that the torque transmission member can be relatively stationary with respect to the power supply structure, and the non-rotating electrical components are realized, so that wireless power supply and wireless signal transmission are not required, thereby saving the cost and improving the reliability.

During the use of the electric power-assisted vehicle, the moment input by the foot of a person is transmitted to the torque transmission part 10 through the rotating shaft and then transmitted to the output of the chain wheel. In this process, the torque transmission member 10 is deformed by the torque force to be elastically deformed, and the torque transmission member 10 can be returned to the free state after the torque force disappears.

The torque transmission member 10 is provided with a first detection object 31 and a second detection object 32, and the first detection object 31 and the second detection object 32 each include a

first reflection structure

311, 321 and a

second reflection structure

312, 322. When the torque transmission member 10 rotates and does not deform, the edge of the first reflection structure 311 in the first detection object 31 may be aligned with the edge of the corresponding first reflection structure 321 in the second detection object 32 (a certain machining error may be allowed), and the time and duration of the corresponding group of

first reflection structures

311 and 321 rotating through the position corresponding to the detection assembly 40 are consistent, that is, the phase difference between the detected first signal wave and the detected second signal wave is 0, as shown in the upper and lower groups of signals in fig. 9.

In actual use, since the torque on the torque transmission member 10 is transmitted from the first end to the second end, the torque transmission member 10 may be deformed during the torque transmission process, and the first reflection structure 311 in the first detection object 31 and the corresponding first reflection structure 321 in the second detection object 32 may move relatively, so that the phase difference between the detected first signal wave and the detected second signal wave changes. The amount of change in the phase difference, that is, the torsion angle generated in response to the deformation of the torque transmission member 10, can be used to determine the torque output from the torque transmission member 10 based on the torsion angle and the elastic modulus of the torque transmission member 10.

In addition, the rotation speed of the torque transmission member 10 can be determined according to the time corresponding to one of the

first reflection structures

311 and 321 in the first signal wave or the second signal wave, so that the torque and the rotation speed can be simultaneously detected by using one torque sensor without simultaneously providing the torque sensor and the rotation speed sensor. Further, since the period of the first signal wave and the second signal wave measured when the torque transmission member 10 is not rotated is infinite, the phase difference between the first signal wave and the second signal wave cannot be measured, and the output torque is 0, the torque sensor does not output torque or the output torque is zero when the transmission is not performed.

Since the magnitude of the torque output from the assist motor of the electric assist vehicle and the magnitude of the detected torque are positively correlated, that is, the detected torque indicates the intention of the rider, and the larger the detected torque, the faster the rider wants to ride, the larger the assist motor can output the larger torque. Meanwhile, the torque sensor can ensure that the output torque is 0 when the torque transmission member 10 is not rotated, and thus the above-described feature of the torque sensor ensures that the assist motor does not output torque when the rider does not pedal the pedal of the electric assist vehicle (i.e., when the detected torque is 0), which can ensure the safety of the electric assist vehicle.

According to another aspect of the present invention, an electric power assisted vehicle is provided, which includes a frame, a rotating shaft, a torque sensor, and a power take-off wheel. The rotating shaft is rotatably arranged on the frame. The torque sensor comprises a torque transmission piece 10, a detection component 40, a first detection object 31 and a second detection object 32, wherein the torque transmission piece 10 is sleeved outside a rotating shaft, the torque transmission piece 10 comprises a first end and a second end, and the first end is mechanically connected with the rotating shaft, the first detection object 31 and the second detection object 32 are arranged on the torque transmission member 10, the detecting assembly 40 is fixedly arranged on the vehicle frame, the detecting assembly 40 is used for detecting the first detecting object 31 to obtain a first signal wave, the detecting assembly 40 is used for detecting the second detecting object 32 to obtain a second signal wave, the phase difference between the first signal wave and the second signal wave is used for determining the relative torsion angle between the detected cross section of the first detecting object 31 and the detected cross section of the second detecting object 32, and the relative torsion angle is used for determining the torque transmitted on the torque transmitting element 10. The power take-off wheel is connected to the second end of the torque transmission member 10 so that the torque transmission member 10 rotates the power take-off wheel.

The electric power assisted vehicle is mainly different from the electric power assisted vehicle in the foregoing embodiment in that the torque sensor in the electric power assisted vehicle may not include a housing, but the detecting assembly 40 is fixed on the vehicle frame, and besides, the structure and effect of the electric power assisted vehicle may be the same as or similar to those of the electric power assisted vehicle in the foregoing embodiment, and thus, the description thereof is omitted.

It should be noted that the terms "first" and "second" in the description of the present invention are used merely for convenience in describing different components or names, and are not to be construed as indicating or implying a sequential relationship, relative importance, or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the utility model herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model.

It should be noted that, although the specific embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention should not be construed as limited to the scope of the present invention. Various modifications and changes may be made by those skilled in the art without inventive step within the scope of the present invention as described in the appended claims.

The examples of the embodiments of the present invention are intended to briefly describe the technical features of the embodiments of the present invention, so that those skilled in the art can intuitively understand the technical features of the embodiments of the present invention, and the embodiments of the present invention are not unduly limited.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. A torque sensor, comprising:

a housing (50);

a torque transfer member (10), the torque transfer member (10) being adapted to be connected to a torque input member (20) for transferring torque input by the torque input member (20), the torque transfer member (10) being rotatable relative to the housing (50);

a first detection object (31) and a second detection object (32) that are provided on the torque transmission member (10) and that are separated by a predetermined distance in an axial direction of the torque transmission member (10);

the detection assembly (40) is arranged on the shell (50), the detection assembly (40) is used for sensing the first detection object (31) to obtain a first signal wave, the detection assembly (40) is used for sensing the second detection object (32) to obtain a second signal wave, the phase difference between the first signal wave and the second signal wave is used for determining the relative torsion angle between the detected cross section of the first detection object (31) and the detected cross section of the second detection object (32), and the relative torsion angle is used for determining the torque transmitted on the torque transmission piece (10).

2. The torque sensor according to claim 1, characterized in that the torque sensor comprises a processing unit connected with the detection assembly (40) to receive the first signal wave and the second signal wave output by the detection assembly (40) and determine a relative torsion angle between the detected cross section of the first detection object (31) and the detected cross section of the second detection object (32) according to a phase difference between the first signal wave and the second signal wave.

3. The torque sensor according to claim 2, wherein the processing unit is further configured to determine a rotational speed of the torque transmitting member (10) based on at least one of the first signal wave and the second signal wave output by the detection assembly (40).

4. The torque sensor according to claim 1, wherein the torque transmission member (10) includes a first end section (11), a connection section (12), and a second end section (13) that are sequentially arranged in the axial direction, the first detection object (31) is at least partially disposed on the first end section (11), the second detection object (32) is at least partially disposed on the second end section (13), and when the torque transmission member (10) transmits the torque and is torsionally deformed, a relative torsion angle between cross sections at both ends of the connection section (12) is a first angle, a relative torsion angle at both ends of the first end section (11) is a second angle, a relative torsion angle at both ends of the second end section (13) is a third angle, and the first angle is greater than at least one of the second angle and the third angle.

5. The torque sensor according to any one of claims 1 to 4, wherein the torque transmission member (10) includes a first end section (11), a connection section (12), and a second end section (13) which are arranged in this order in the axial direction, the first detection object (31) is provided to at least a part of the first end section (11), the second detection object (32) is provided to at least a part of the second end section (13), and an elastic coefficient of the connection section (12) is lower than an elastic coefficient of at least one of the first end section (11) and the second end section (13).

6. The torque sensor according to any one of claims 1 to 4, wherein the torque transmission member (10) includes a first end section (11), a connecting section (12), and a second end section (13) arranged in this order in the axial direction, the first detection object (31) is provided to at least a part of the first end section (11), the second detection object (32) is provided to at least a part of the second end section (13), and a length of the connecting section (12) is greater than a length of at least one of the first end section (11) and the second end section (13).

7. Torque sensor according to claim 5, wherein said connection section (12) has a wall thickness smaller than the wall thickness of said first end section (11) and said second end section (13).

8. Torque sensor according to claim 5, wherein said connection section (12) is provided with a first groove (121) so that the spring constant of said connection section (12) is lower than the spring constant of at least one of said first end section (11) and said second end section (13).

9. The torque sensor according to any one of claims 1 to 4, wherein the detection assembly (40) comprises a photoelectric sensor, the first detection object (31) and the second detection object (32) each comprise a first reflective structure (311, 321) and a second reflective structure (312, 322) disposed alternately in a circumferential direction of the torque transmission member (10), the first reflective structure (311, 321) and the second reflective structure (312, 322) having different reflectivities.

10. The torque sensor according to claim 9, wherein the first reflective structure (311, 321) comprises stripes having a first reflectivity arranged on the circumferential surface of the torque transmitter (10), and the second reflective structure (312, 322) comprises stripes having a second reflectivity arranged on the circumferential surface of the torque transmitter (10), the first reflectivity not being equal to the second reflectivity.

11. The torque sensor according to claim 9, wherein the first reflecting structure (311, 321) comprises a plurality of protrusions, the plurality of protrusions being arranged at intervals in a circumferential direction of the torque transmitting member (10).

12. The torque sensor of claim 11, wherein the second reflective structure (312, 322) comprises a plurality of second grooves disposed between two adjacent protrusions.

13. The torque sensor according to claim 9, wherein a plurality of the first reflection structures (311, 321) are provided in a circumferential direction of the torque transmission member (10), and a plurality of the first reflection structures (311, 321) are different in size in the circumferential direction of the torque transmission member (10).

14. The torque sensor according to any one of claims 1 to 4, wherein the sense assembly (40) comprises an eddy current sensor, the first and second senses (31, 32) each comprising first and second magnetically permeable structures arranged circumferentially spaced apart along the torque transfer member (10), the reluctance formed between the first magnetically permeable structure and the sense assembly (40) being different from the reluctance formed between the second magnetically permeable structure and the sense assembly (40).

15. Torque sensor according to any one of claims 1 to 4, further comprising an angle detector for detecting the angle of rotation of said torque transmitter (10) with respect to said detection assembly (40) at the section of said angle detector.

16. The torque sensor according to claim 15, wherein the angle detector comprises a magnetic ring (61) and a hall sensor (62), the magnetic ring (61) comprises at least one pair of magnetic poles arranged along a circumferential direction of the torque transmission member (10), the hall sensor (62) is arranged on the housing (50) to determine a rotation angle of the torque transmission member (10) relative to the detection assembly (40) at a cross section where the magnetic pole pair is located according to a third signal wave obtained by detecting the magnetic pole pair, and the rotation angle is used for determining an error compensation amount for the relative torsion angle.

17. The torque sensor according to claim 1, wherein the first end of the torque transmitting member (10) is provided with an internal thread for cooperation with an external thread provided on the torque input member (20).

18. An electric power assisted vehicle, characterized by comprising:

a frame;

the rotating shaft is rotatably arranged on the frame and is used for receiving external torque;

the torque sensor comprises a torque transmission piece (10), a shell (50), a detection component (40), a first detection object (31) and a second detection object (32), wherein the shell (50) is fixedly arranged on the frame, the torque transmission piece (10) is sleeved outside the rotating shaft, the torque transmission piece (10) comprises a first end and a second end, the first end is connected with the rotating shaft, so that the rotating shaft drives the torque transmission piece (10) to rotate, the first detection object (31) and the second detection object (32) are arranged on the torque transmission piece (10) and are separated by a preset distance in the axial direction of the torque transmission piece (10), the detection component (40) is used for detecting the first detection object (31) to obtain a first signal wave, and the detection component (40) is used for detecting the second detection object (32) to obtain a second signal wave, the phase difference between the first signal wave and the second signal wave is used for determining a relative torsion angle between the detected section of the first detection object (31) and the detected section of the second detection object (32), and the relative torsion angle is used for determining the torque transmitted on the torque transmission piece (10); and

and the power output wheel is connected with the second end of the torque transmission piece (10) so that the torque transmission piece (10) drives the power output wheel to rotate.

19. The electric assist vehicle according to claim 18, further comprising a processing unit electrically connected to the detection member (40) of the torque sensor to receive the first signal wave and the second signal wave output from the detection member (40), and to determine a relative torsion angle between the detected cross section of the first detection object (31) and the detected cross section of the second detection object (32) according to a phase difference between the first signal wave and the second signal wave.

20. Electric assisted vehicle according to claim 19, characterized in that the processing unit is also adapted to determining the rotation speed of the torque transfer member (10) from at least one of the first and second signal waves output by the detection assembly (40).

21. The electric power-assisted vehicle according to claim 18, wherein the torque transmission member (10) includes a first end section (11), a connecting section (12) and a second end section (13) which are sequentially arranged in the axial direction, the first detection object (31) is at least partially arranged on the first end section (11), the second detection object (32) is at least partially arranged on the second end section (13), when the torque transmission member (10) transmits torque and is torsionally deformed, a relative torsion angle between cross sections at both ends of the connecting section (12) is a first angle, a relative torsion angle at both ends of the first end section (11) is a second angle, a relative torsion angle at both ends of the second end section (13) is a third angle, and the first angle is larger than at least one of the second angle and the third angle.

22. An electric power-assisted vehicle according to any one of claims 18-21, characterized in that the torque transmission member (10) comprises a first end section (11), a connecting section (12) and a second end section (13) arranged in the axial direction in this order, the first detection object (31) being arranged at least in part of the first end section (11), the second detection object (32) being arranged at least in part of the second end section (13), the connecting section (12) having a lower coefficient of elasticity than at least one of the first end section (11) and the second end section (13).

23. An electric power assisted vehicle according to any of claims 18-21, characterized in that the torque transfer member (10) comprises a first end section (11), a connecting section (12) and a second end section (13) arranged in the axial direction in sequence, the first detection object (31) being arranged at least partly at the first end section (11) and the second detection object (32) being arranged at least partly at the second end section (13), the connecting section (12) having a length larger than the length of at least one of the first end section (11) and the second end section (13).

24. An electric power assisted vehicle according to claim 22, characterized in that the wall thickness of the connecting section (12) is smaller than the wall thickness of the first end section (11) and the second end section (13).

25. An electric power assisted vehicle according to claim 22, characterized in that the connecting section (12) is provided with a first groove (121) such that the connecting section (12) has a lower spring constant than at least one of the first end section (11) and the second end section (13).

26. An electric power assisted vehicle according to any of claims 18-21, characterized in that the detection assembly (40) comprises a photo sensor, that the first detection object (31) and the second detection object (32) each comprise a first reflecting structure (311, 321) and a second reflecting structure (312, 322) arranged mutually in the circumferential direction of the torque transfer part (10), the reflectivity of the first reflecting structure (311, 321) and the second reflecting structure (312, 322) being different.

27. An electric power assisted vehicle according to claim 26, characterized in that the first reflecting structure (311, 321) comprises stripes of a first reflectivity arranged on the circumference of the torque transferring member (10) and the second reflecting structure (312, 322) comprises stripes of a second reflectivity arranged on the circumference of the torque transferring member (10), the first reflectivity not being equal to the second reflectivity.

28. An electric power assisted vehicle according to claim 26, characterized in that the first reflecting structure (311, 321) comprises a plurality of protrusions which are arranged at intervals in the circumferential direction of the torque transferring member (10).

29. An electric power-assisted vehicle according to claim 28, characterized in that the second reflecting structure (312, 322) comprises a plurality of second grooves, which are arranged between two adjacent protrusions.

30. An electric power assisted vehicle according to claim 26, characterized in that a plurality of the first reflecting structures (311, 321) are provided in the circumferential direction of the torque transmission member (10), the plurality of the first reflecting structures (311, 321) differing in size in the circumferential direction of the torque transmission member (10).

31. An electrically assisted vehicle according to any of claims 18-21, characterized in that the detecting assembly (40) comprises an eddy current sensor, the first (31) and second (32) targets each comprising first and second magnetically conductive structures arranged circumferentially spaced apart along the torque transfer member (10), the magnetic reluctance formed between the first magnetically conductive structure and the detecting assembly (40) being different from the magnetic reluctance formed between the second magnetically conductive structure and the detecting assembly (40).

32. Electric assisted vehicle according to any of claims 18 to 21, characterized in that the torque sensor further comprises an angle detector for detecting the angle of rotation of the torque transmitter (10) with respect to the detection assembly (40) at the section of the angle detector.

33. The electric assist vehicle according to claim 32, wherein the angle detector includes a magnetic ring (61) and a hall sensor (62), the magnetic ring (61) includes at least one pair of magnetic pole pairs arranged along a circumferential direction of the torque transmission member (10), the hall sensor (62) is arranged in the housing (50) to determine a rotation angle of the torque transmission member (10) with respect to the detection assembly (40) at a cross section where the magnetic pole pair is located according to a third signal wave obtained by detecting the magnetic pole pair, and the rotation angle is used to determine an error compensation amount for the relative torsion angle.

34. An electric power assisted vehicle according to claim 18, characterized in that the first end of the torque transfer member (10) is provided with an internal thread and the shaft is provided with an external thread, the torque transfer member (10) being connected to the shaft by means of the internal thread and the external thread.

35. An electric power assisted vehicle, characterized by comprising:

a frame;

the rotating shaft is rotatably arranged on the frame;

the torque sensor comprises a torque transmission piece (10), a detection component (40), a first detection object (31) and a second detection object (32), wherein the torque transmission piece (10) is sleeved outside the rotating shaft, the torque transmission piece (10) comprises a first end and a second end, the first end is mechanically connected with the rotating shaft, the first detection object (31) and the second detection object (32) are arranged on the torque transmission piece (10) and are separated from each other in the axial direction of the torque transmission piece (10) by a preset distance, the detection component (40) is fixedly arranged on the frame, the detection component (40) is used for detecting that the first detection object (31) obtains a first signal wave, the detection component (40) is used for detecting that the second detection object (32) obtains a second signal wave, and the phase difference between the first signal wave and the second signal wave is used for determining the quilt of the first detection object (31) A relative torsion angle between the detection cross section and the detected cross section of the second detection object (32), wherein the relative torsion angle is used for determining the torque transmitted on the torque transmission piece (10); and

36. A torque sensor, comprising:

a housing;

the rotating shaft can rotate relative to the shell;

the torque barrel is used for being connected with the rotating shaft so as to transmit torque input by the rotating shaft;

the first detection object and the second detection object are arranged on the torsion cylinder and are separated by a preset distance in the axial direction of the torsion cylinder; and

the detection assembly is arranged on the shell and is static relative to the shell, the detection assembly is used for detecting the first detection object to generate a first signal wave, the detection assembly is used for detecting the second detection object to generate a second signal wave, the phase difference between the first signal wave and the second signal wave is used for determining the relative torsion angle between the detected cross section of the first detection object and the detected cross section of the second detection object, and the relative torsion angle is used for determining the torque transmitted by the torsion cylinder.

37. The torque transducer according to claim 36, wherein the first end of the torque barrel is provided with an internal thread and the shaft is provided with an external thread, and the torque barrel and the shaft are connected by the internal thread and the external thread.