TWI809840B - Electric Bicycle Pedal Torque Sensing Device - Google Patents

Abstract

A pedaling torque sensing device of an electric bicycle, in which a second outer ring gear is rotatably arranged in combination with a first outer ring gear in a casing, the second outer ring gear is combined with a torsion element whose end is fixed and a strain gauge is provided on the surface, Each of the first outer ring gear and the second outer ring gear meshes with a set of planetary gears that are co-moved on the planet carrier. A crankshaft is provided to pass between the gears of the two sets of planetary gears, and the crankshaft passes through the gears of the two sets of planetary gears. A set of planetary gears is driven to the second outer ring gear, and the other set of planetary gears is linked to drive the output end of an output hollow tube to rotate; when the present invention is used, it is set on the frame of an electric bicycle. When under load, the torsion force of turning the crankshaft will twist the torsion element, so that the strain gauge senses the torsion force of the crankshaft being pedaled and rotated, which serves as the basis for the magnitude of the electric auxiliary power output.

Description

Electric Bicycle Pedal Torque Sensing Device

The invention relates to a sensing device for a bicycle, in particular to a pedaling torque sensing device for an electric bicycle.

Existing electric bicycles are divided into electric bicycles with a middle motor and electric bicycles with a rear motor according to the position of the motor. The electric bicycle with the middle motor is provided with the motor drive system at the position corresponding to the bottom bracket of the bicycle frame, while the bicycle with the rear motor is equipped with a hub motor at the axis of the rear wheel.

When the above-mentioned electric bicycle is ridden with motor-assisted power, the auxiliary power output by the electric motor is determined by detecting the pedal torque. When detecting the magnitude of the pedaling torque, a strain gauge is usually installed on the chainring, and the deformation of the chainring is sensed by the strain gauge to obtain the torque of the pedal-driven bicycle. However, the position where the torque is measured through the chainring is close to the pedal power output The end of the power transmission lacks the means to measure the torque at the front end.

In view of this, the purpose of the present invention is to provide a pedaling torque sensing device for electric bicycles to sense the torque value of the crankshaft twisted by the pedals, which can provide the basis for the power assist output of the electric bicycle.

In order to achieve the above object, the present invention provides a pedaling torque sensing device of an electric bicycle, comprising: a housing; a first outer ring gear, combined in the housing; a torque The conduction assembly includes a second outer ring gear and a torsion element, the second outer ring gear is rotatably arranged in the casing, one end of the torsion element is combined with the second outer ring gear, and the other end is fixed relative to the casing ; a strain gauge, combined on the surface of the torsion element; a planetary gear structure, a planetary carrier is provided, a plurality of first planetary gears are pivoted around one side of the planetary carrier, and a plurality of first planetary gears are pivoted around the other side of the planetary carrier; Several second planetary gears, the outer sides of the first planetary gears mesh with the first outer ring gear, and the outer sides of the second planetary gears mesh with the second outer ring gear; and a transmission assembly, including a crankshaft and a The output hollow tube, the crank shaft passes through the center of the torque transmission assembly and the planetary gear structure, the crank shaft has a driving sun gear, the driving sun gear meshes with the inner side of the second planetary gears, the output hollow A tube is rotatably sleeved around the crankshaft, one end of the output hollow tube has an output sun gear, and the output sun gear meshes with the insides of the first planetary gears, and the other end of the output hollow tube has An output end is used to drive the toothed plate of the electric bicycle to rotate.

When the present invention is in use, it is arranged at the position corresponding to the bottom bracket of the vehicle frame of the electric bicycle, the two ends of the crank shaft are combined with the crank and the pedal, and the output end of the output hollow tube is connected with the chainring for driving the chain. When the rider of the electric bicycle steps on two pedals to turn the crank shaft, the driving sun gear will drive the first planetary gears to rotate the planetary carrier, and then drive the output sun gear through the linked second planetary gears to make the output The hollow tube rotates, and the output end drives the chainring and the chain to rotate.

The effect of the present invention is that when the driving sun gear of the crankshaft drives the first planetary gears to rotate, the torsional force on the second outer ring gear, which is restricted by the torsion element and does not rotate, will be transmitted to the torsion element to make the torsion element The torsion is deformed, and the strain gauge arranged on the surface of the torsion element measures the torsion value of the crankshaft driven by the pedal, which can be used as a judgment basis for controlling the auxiliary power output of the electric motor.

〔this invention〕

100: pedaling torque sensing device

200: Rangefinder mid-mounted motor system

300: Coaxial mid-mounted motor system

10: Shell

11: horizontal groove

12: Assembly space

13: inner ring

131: block

14: Tubular body

141: The first keyway

142: Second keyway

16: First end cap

161: First piercing

162: The first bearing

18:Second end cap

181:Second perforation

20: The first outer ring gear

21: Bump

22: The first key base

24: First key block

30: Torque transmission components

32: Second external ring gear

34: Torsion element

341: link ring

3411: transmission gear

342: fixed ring

3421:Second key base

3422: Second key block

3423: bearing seat

3424: Second bearing

3425: Concave

343: Neck

40: Planetary gear structure

42:Planet carrier

44: The first planetary gear

46: Second planetary gear

50: Transmission components

52: crankshaft

521: Driving sun gear

54: output hollow tube

541: Output sun gear

542: output terminal

56: One-way bearing

60: Bicycle Rack

62: Crank

621: Pedal

64: chainring

641: Outer bearing seat

642: Chainring drive teeth

70:Motor seat

72: Electric motor room

74: Sensing device room

76:Electric motor

761: deceleration mechanism

762: Electric output gear

763: Stator

764: rotor

765: Motor output shaft

766: Deceleration output terminal

77: One-way bearing

78: Installation room

A: Strain gauge

Fig. 1 is a perspective view of the first preferred embodiment of the present invention.

Fig. 2 is a perspective view of the separation transmission assembly and the second end cover of the first preferred embodiment of the present invention.

Fig. 3A is an exploded view of the first preferred embodiment of the present invention.

Fig. 3B is an exploded view from another angle of the first preferred embodiment of the present invention.

Fig. 4 is a cross-sectional view along line 4-4 of Fig. 1 .

Fig. 5 is a perspective view of the first preferred embodiment of the present invention installed in the rangefinder mid-mounted motor system.

Fig. 6 is a side view of the first preferred embodiment of the present invention, which is installed in the mid-range motor system of the rangefinder.

Fig. 7 is a sectional view along line 7-7 of Fig. 6 .

Fig. 8 is a sectional view taken along line 8-8 in Fig. 6 .

Fig. 9 is a perspective view of a second preferred embodiment of the present invention arranged in a coaxial mid-mounted motor system.

Fig. 10 is a side view of the second preferred embodiment of the present invention set in the coaxial mid-mounted motor system.

FIG. 11A is an exploded view of the coaxial mid-mounted motor system in FIG. 9 with the motor seat removed.

FIG. 11B is an exploded view of the coaxial mid-mounted motor system in FIG. 9 with the motor seat removed from another angle.

Fig. 12 is a sectional view taken along line 12-12 in Fig. 10 .

In order to illustrate the present invention more clearly, preferred embodiments are given and detailed descriptions are given below in conjunction with drawings. Please refer to Fig. 1 to Fig. 4, which is a pedaling torque sensing device 100 of the first preferred embodiment of the present invention, which is used to be installed on an electric bicycle to measure the torque of the rider pedaling on the pedal of the electric bicycle. The structure of pedaling torque sensing device 100 includes a housing 10, a The first outer ring gear 20, a torque transmission assembly 30, a strain gauge A, a planetary gear structure 40 and a transmission assembly 50, wherein: the housing 10 has an assembly space 12 inside, in this preferred embodiment the The assembly space 12 is a horizontal cylindrical space.

The first outer ring gear 20 is an annular body with a plurality of teeth surrounding the inner peripheral surface. The first outer ring gear 20 is arranged in the assembly space 12 and combined in the housing 10. The first outer ring gear 20 is opposite to the The housing 10 is fixed and does not rotate. In some embodiments, the first external ring gear 20 is fixed to the housing 10 with a concave-convex fitting structure between the two. In other embodiments, the first external ring gear is directly 20 is set as an integral structure with the housing 10 , or both are bonded or welded to achieve the purpose of combining the first external ring gear 20 in the housing 10 to be fixed and not rotate.

The torque transmission assembly 30 includes a second outer ring gear 32 and a torsion element 34. The second outer ring gear 32 is a ring with a plurality of teeth surrounding its inner peripheral surface. The second outer ring gear 32 and the first outer ring gear 32 The outer ring gear 20 is side by side and arranged concentrically in the assembly space 12. Compared with the first outer ring gear 20 which does not rotate relative to the housing 10, the second outer ring gear 32 is arranged in the housing rotatably. 10 , the number of teeth of the first outer ring gear 20 and the second outer ring gear 32 are the same; The strain gauge A is combined with the surface of the torsion element 34 , and the preferred location of the strain gauge A is the most obvious torsional deformation position of the torsion element 34 such as the surface of the middle part of the torsion element 34 .

The planetary gear structure 40 is provided with a planet carrier 42, the planet carrier 42 is a hollow cylindrical frame and straddles the inside of the first outer ring gear 20 and the second outer ring gear 32, the planet carrier 42 has Several first planetary gears 44 are pivoted around one side of the two sides in a circular and spaced arrangement. The outer sides of these first planetary gears 44 mesh with the first outer ring gear 20 . Several second planets are pivoted in a circumferential and spaced arrangement around the gear 46, the outer side of the second planetary gears 46 meshes with the second outer ring gear 32, since the first planetary gears 44 and the second planetary gears 46 are pivotally mounted on the same planetary carrier 42 so as to be Simultaneous rotation or non-rotating structure, and in this preferred embodiment, the first planetary gears 44 and the second planetary gears 46 are the same number and the individual first planetary gears 44 and the second planetary gears 46 are coaxial or Concentric arrangement with the same number of teeth.

The transmission assembly 50 includes a crank shaft 52 and an output hollow tube 54, the middle part of the crank shaft 52 passes through the center of the torque transmission assembly 30 and the planetary gear structure 40, specifically the crank shaft 52 passes through the second An outer ring gear 20, a second outer ring gear 32 and the center of the planet carrier 42 pass between the first planetary gears 44 and the second planetary gears 46, and the left and right ends of the crankshaft 52 pass through The housing 10 has an assembly space 12 . The crankshaft 52 has a driving sun gear 521, the driving sun gear 521 is sleeved and fixed through the spline structure and combined with the crankshaft 52, in other preferred embodiments, the driving sun gear 521 can also be connected with the crankshaft The crankshaft 52 is integrally formed; the driving sun gear 521 meshes with the inner sides of the second planetary gears 46 .

The output hollow tube 54 is a tubular body and is rotatably sleeved around the crankshaft 52. One end of the output hollow tube 54 extends into the assembly space 12 of the housing 10 and the end has an output sun gear 541. , the output sun gear 541 meshes with the inner sides of the first planetary gears 44, the other end of the output hollow tube 54 protruding from the casing 10 has an output end 542, and the output end 542 is used to drive the gears of the electric bicycle The structure of disc rotation; for example, in this preferred embodiment, the output end 542 is a one-way bearing seat and a one-way bearing 56 is combined around it, and in order to make the rotational speed input by the crankshaft 52 equal to that output by the hollow tube 54 Rotational speed, in response to the above-mentioned design that the first planetary gear 44 and the second planetary gear 46 have the same number of teeth and the first outer ring gear 20 and the second outer ring gear 32 have the same number of teeth, the driving sun gear 521 and the output The sun gear 541 is set to have the same number of teeth.

In addition to the above-mentioned preferred embodiment, the present invention sets the first planetary gear 44 and the second planetary gear 46 to have the same number and number of teeth, and the first outer ring gear 20 and the second outer ring gear 32 to have the same teeth number of teeth, and the output sun gear 541 and the driving sun gear 521 are set to have the same number of teeth, the first planetary gear 44 and the second planetary gear 46 can also be set to different numbers, such as three first planetary gears 44 Coordinating with the number of five second planetary gears 46, individual first planetary gears 44 and second planetary gears 46 can also be coaxial/non-axial or concentric/non-centric, and the number of teeth of the above-mentioned same type of gears is not limited to the same , as long as the reduction ratio of the first planetary gear 44, the first outer ring gear 20 and the output sun gear 541 and the reduction ratio of the second planetary gear 46, the second outer ring gear 32 and the driving sun gear 521 are satisfied Under the same conditions, it is sufficient to make the rotational speed input by the crankshaft 52 equal to the rotational speed output by the hollow tube 54 .

Please refer to FIG. 4 and FIG. 5 to FIG. 8 . When the pedaling torque sensing device 100 according to the first preferred embodiment of the present invention is used, it is installed in the mid-range motor system 200 . The rangefinder mid-mounted motor system 200 is combined with a motor mount 70 at a position corresponding to the bottom bracket of a bicycle frame 60, and the front and rear sides of the motor mount 70 respectively have an electric motor chamber 72 and a sensing device chamber 74, the electric motor chamber 72 is equipped with an electric motor 76, the electric motor 76 has a controller for signal receiving the data of the torque sensed by the strain gauge A, the output shaft of the electric motor 76 is connected to an electric output gear through a reduction mechanism 761 762 , the power output by the electric motor 76 is proportional to the torque sensed by the strain gauge A that the torsion element 34 bears.

The pedaling torque sensing device 100 of the present invention is installed in the sensing device chamber 74, the left and right ends of the crank shaft 52 protrude from the sensing device chamber 74 and are respectively combined with a crank 62, and the end of the crank 62 is combined with a pedal 621 . There is a chainring 64, which is located between the crank 62 on the right side and the output end 542. The chainring 64 surrounds the crankshaft 52, and the left side of the toothing 64 is concentrically combined with an annular outer Bearing seat 641, the one-way bearing 56 is embedded in the In the outer bearing seat 641, a plurality of chainring drive teeth 642 are formed around the outer peripheral surface of the outer bearing seat 641. The electric motor 76 is connected to a reduction mechanism 761, and the reduction mechanism 761 is transmitted to a one-way bearing 77, and the The outer ring of the one-way bearing 77 is combined with an electric output gear 762, and the electric output gear 762 meshes with several chainring drive teeth 642 on one side around the outer bearing seat 641, and the electric output gear 762 is arranged in a one-way direction. The structure of the outer ring of the bearing 77 enables the rider to pedal while the electric motor 76 does not carry out power output, avoiding the resistance caused by the hysteresis effect of the electric motor 76 itself, causing the rider to take more effort. Pedaling to avoid bad rider experience.

When the electric bicycle rider steps on the two pedals 621 to rotate the crankshaft 52, it will drive the crankshaft 52 and the driving sun gear 521 to rotate, and the rotation of the driving sun gear 521 will drive the first planetary gears 44 along the second When the outer ring gear 32 rotates, the second planetary gears 46 arranged on the same planet carrier 42 as the first planetary gears 44 will move together with the first planetary gears 44, so that the second planetary gears 46 will move along the The first outer ring gear 20 fixed relative to the casing 10 rotates, driving the output sun gear 541, the output hollow tube 54 and the output end 542 of the transmission assembly 50 to rotate, and finally driven by the one-way bearing 56 through the outer bearing seat 641 The chainring 64 rotates.

In the process of stepping on the two pedals 621 to rotate the crankshaft 52 to drive the chainring 64 to rotate, due to the speed reduction ratio of the first planetary gears 44, the first outer ring gear 20 and the output sun gear 541 and the second planetary gears The gear 46, the second external ring gear 32 and the driving sun gear 521 have the same speed reduction ratio, so the crankshaft 52 and the chainring 64 connected to the transmission assembly 50 will rotate concentrically, at the same speed and with the same direction of rotation, making the application of the present invention The setting of the electric bicycle when stepping on the two pedals 621 is consistent with that of commercially available bicycles, so as to avoid the inconsistency between the number of turns of the crankshaft 52 and the number of turns of the chainring 64 due to the rider's stepping, resulting in additional misunderstandings and bad impressions.

During the process of stepping on the second pedal 621 to make the stepping torque sensing device 100 drive the chainring 64, when the driving sun gear 521 of the crankshaft 52 drives the first planetary gears 44 to rotate, although the second outer ring gear 32 can rotate freely relative to the housing 10, but because the second external ring gear 32 has the torsion element 34 that is fixed at the end relative to the housing 10 and does not rotate, the rotation of the second external ring gear 32 is affected by the torsion element 34 limit, at this time, the torsional force driven by the first planetary gears 44 to rotate the second outer ring gear 32 will be transmitted to the torsion element 34, causing the torsion element 34 to be deformed by the force of torsion. The strain gauge A on the surface can feel and measure the value of the torque, so that the controller of the electric motor 76 can judge whether it needs to output auxiliary power.

When the controller of the electric motor 76 judges that it is necessary to output auxiliary power, it will drive the electric output gear 762 to drive the toothed disc 64 to rotate. , can also add the auxiliary power of the electric motor 76, so that if the resistance increases when the rider of the electric bicycle pedals, that is, when the load of the crankshaft 52 and the output hollow tube 54 is lifted, the strain gauge can pass through the electric bicycle. The torque change measured by A increases the power output of the electric motor 76, and the power assisted by the electric motor 76 makes pedaling more labor-saving when riding.

To further illustrate the structure of the pedaling torque sensing device 100 according to the first preferred embodiment of the present invention, please refer to FIG. 1 to FIG. Several first key slots 141 have several second key slots 142 on the left side. The right end of the tubular body 14 adjacent to the first keyway 141 is screwed together with a first end cap 16, the middle of the first end cap 16 has a first through hole 161, and a first end cap 16 is embedded inside Bearing 162, the left end of the tubular body 14 adjacent to the second keyway 142 is screwed with a second end cover 18, the middle of the second end cover 18 has a second through hole 181, the right end of the crankshaft 52 Through the first through hole 161 , the left end of the crankshaft 52 passes through the second through hole 181 , and the right part of the crankshaft 52 passes through the first bearing 162 .

The outer peripheral surface of the first outer ring gear 20 has several first key seats 22, the first key seats 22 are opposite to the first key groove 141, and a first key block 24 is embedded in both, so that the first key seat 22 The outer ring gear 20 is combined and fixed in the housing 10 and cannot rotate. And in other preferred embodiments, the housing 10 may only be provided with a first keyway 141 for matching with a first key seat 22 of the first outer ring gear 20 and a first key seat 22 embedded in both. The key block 24 can also combine and fix the first outer ring gear 20 in the casing 10 so as not to rotate.

The torsion element 34 includes a connecting ring 341, a fixed ring 342 and a neck 343 connected between the connecting ring 341 and the fixing ring 342, the connecting ring 341 is concentrically combined with the second outer ring gear 32. In this preferred embodiment, there is a transmission gear 3411 around the connecting ring 341, the transmission gear 3411 is coaxial with the second outer ring gear 32 and the transmission gear 3411 meshes with the second outer ring gear 32 for a full circle; In other preferred embodiments, the peripheral edge of the connecting ring 341 can be connected to the end edge of the second outer ring gear 32 , so that the second outer ring gear 32 and the torsion element 34 are integrated.

The outer peripheral surface of the fixing ring 342 has several second key seats 3421, the second key seats 3421 are opposite to the second key groove 142 and a second key block 3422 is embedded in both, so that the fixing ring 342 Combined in the housing 10 and fixed relative to the housing 10 and cannot rotate; and in other preferred embodiments, the housing 10 may only be provided with a second keyway 142 for matching a second key that the fixing ring 342 has The seat 3421 and the second key block 3422 embedded in both can also combine and fix the fixing ring 342 in the housing 10 so as not to rotate. The inner side of the fixing ring 342 has a bearing seat 3423 , the bearing seat 3423 is embedded with a second bearing 3424 , and the left part of the crankshaft 52 passes through the second bearing 3424 . The neck 343 is a tube, the One end of the neck 343 is connected to the inner periphery of the connecting ring 341 , and the other end is connected to the inner periphery of the fixing ring 342 . The strain gauge A is combined on the surface of the neck 343 .

In addition to the first preferred embodiment of the present invention, the pedaling torque sensing device 100 is set in the rangefinder type mid-mounted motor system 200, as shown in Figures 9 to 12, it can also be set in the coaxial type The type of motor system 300 is set.

In the second preferred embodiment, the pedaling torque sensing device 100 also includes a housing 10, a first outer ring gear 20, a torque transmission component 30, a strain gauge A, a planetary gear structure 40 and a transmission component 50 . The first outer ring gear 20 is combined in the housing 10 and cannot rotate. The torque transmission assembly 30 includes a second outer ring gear 32 and a torsion element 34. The second outer ring gear 32 is connected to the first outer ring gear 20. Concentric and juxtaposed left and right, the second external ring gear 32 is rotatably arranged in the casing 10, the torsion element 34 has two ends and one end is combined with the second external ring gear 32, and the other end is fixed relative to the casing 10. turn. The strain gauge A is combined with the surface of the torsion element 34 and the preferred combination position is the surface of the middle part of the torsion element 34 .

The planetary gear structure 40 is provided with a planet carrier 42, the planet carrier 42 is a hollow cylindrical frame and straddles the inside of the first outer ring gear 20 and the second outer ring gear 32, the planet carrier 42 has Several first planetary gears 44 are pivoted around one side of the two sides in a circular and spaced arrangement. The outer sides of these first planetary gears 44 mesh with the first outer ring gear 20 . A plurality of second planetary gears 46 are pivotally arranged in a circumferential and spaced arrangement around the outer ring gear 32 , and the outer sides of the second planetary gears 46 mesh with the second outer ring gear 32 .

The transmission assembly 50 includes a crankshaft 52 and an output hollow tube 54. The middle part of the crankshaft 52 passes through the center of the torque transmission assembly 30 and the planetary gear structure 40, and the left and right ends of the crankshaft 52 go through the center. In the housing 10 , the crankshaft 52 has a driving sun gear 521 , and the driving sun gear 521 meshes with the inner sides of the second planetary gears 46 . The output hollow tube 54 is a tube body and partly penetrates the casing 10, and the output hollow tube 54 is rotatably sleeved. Around the crankshaft 52, one end of the output hollow tube 54 has an output sun gear 541, the output sun gear 541 meshes with the inside of the first planetary gears 44, and the output hollow tube 54 protrudes from the housing The other end of 10 has an output end 542, and the output end 542 is a structure used to drive the chainring of the electric bicycle to rotate.

When the pedaling torque sensing device 100 of the second preferred embodiment of the present invention is used, it is installed in the coaxial mid-mounted motor system 300 . The coaxial mid-mounted motor system 300 has a motor base 70, and the motor base 70 has an installation chamber 78. The pedaling torque sensing device 100 is installed and fixed in the installation chamber 78. The left and right ends of the crank shaft 52 Protrude from the installation chamber 78 and combine with a crank 62 respectively, the end of the crank 62 is combined with a pedal 621 . There is a chainring 64, which is located between the crank 62 on the right side and the output end 542. The chainring 64 surrounds the crankshaft 52, and the output end 542 of the output hollow tube 54 is concentrically connected to the chainring. 64.

The first outer ring gear 20 , the torque transmission assembly 30 and the planetary gear structure 40 are all mounted on the left side of the housing 10 , and the coaxial mid-mounted motor system 300 is provided with an electric motor 76 in the middle of the housing 10 , The electric motor 76 has a controller for receiving signals from the torque sensed by the strain gauge A and includes a stator 763 and a rotor 764, which are rotatably sleeved around the output hollow tube 54 in accordance with the position of the rotor 764 A motor output shaft 765. The stator 763 is circumferentially fixed around the housing 10, the rotor 764 is located inside the stator 763 and coupled to the motor output shaft 765, the right end of the motor output shaft 765 is connected to a speed reduction mechanism 761, the speed reduction mechanism 761 The right end has a deceleration output end 766 , the deceleration output end 766 is concentrically connected to the chainring 64 , and the power output by the electric motor 76 is proportional to the torsion force of the torsion element 34 sensed by the strain gauge A.

When the electric bicycle rider steps on the two pedals 621 to rotate the crankshaft 52, it will drive the crankshaft 52 and the driving sun gear 521 to rotate, and the rotation of the driving sun gear 521 will drive the first planetary gears 44 along the second The outer ring gear 32 rotates, with the first row of these The planetary gear 44 is arranged on the same planet carrier 42 and the second planetary gears 46 will move together with the first planetary gears 44, so that the second planetary gears 46 move along the first outer ring gear fixed relative to the housing 10. 20 rotates to drive the output hollow tube 54 with the output sun gear 541 to rotate, and finally the output end 542 drives the toothed disc 64 to rotate.

During the process of stepping on the second pedal 621 to make the stepping torque sensing device 100 drive the chainring 64, the second outer ring gear 32 is restricted by the torsion element 34 and cannot rotate freely. At this time, the first planetary gears 44 drive The torsion force of the rotation of the second outer ring gear 32 will be transmitted to the torsion element 34, so that the torsion element 34 is deformed by the force of torsion, and the strain gauge A arranged on the surface of the torsion element 34 measures the value of the torsion force, so that The controller of the electric motor 76 determines whether it is necessary to output auxiliary power. When the controller of the electric motor 76 judges that it is necessary to output auxiliary power, it will drive the rotor 764 to drive the toothed disc 64 to rotate through the motor output shaft 765 and the reduction mechanism 761. In addition to the power of the pedal of the empty tube 54, the power assisted by the electric motor 76 can also be added, and the power assisted by the electric motor 76 makes the pedaling when riding more labor-saving.

To further illustrate the structure of the pedaling torque sensing device 100 according to the second preferred embodiment of the present invention, please refer to FIGS. There are several transverse grooves 11 on the surface. The transverse grooves 11 are long grooves extending in parallel to the axial direction of the crankshaft 52. An inner diameter smaller than that of other parts of the housing 10 is formed at the left end of the housing 10. Ring 13, the inner peripheral surface of the inner ring 13 has several blocks 131; the outer peripheral surface of the first outer ring gear 20 has several protrusions 21, and these protrusions 21 are embedded in the transverse grooves 11 so that the The first outer ring gear 20 is fixed and cannot rotate relative to the housing 10 .

The torsion element 34 is the same as that described in the first preferred embodiment, including a connecting ring 341 , a fixing ring 342 and a neck 343 connected between the connecting ring 341 and the fixing ring 342 . There is a transmission gear 3411 around the connecting ring 341, and the transmission gear 3411 It is coaxial with the second outer ring gear 32 and the transmission gear 3411 meshes with the second outer ring gear 32 for a full circle. The fixed ring 342 is located inside the inner ring 13 and has several recesses 3425 on the outer peripheral surface. The block 131 is embedded in these recesses 3425, and the fixed ring 342 is combined with the housing 10 so that it cannot rotate. The neck 343 is a tubular body and one end is connected to the inner peripheral edge of the connecting ring 341, and the other end is connected to the inner peripheral edge of the fixed ring 342. , the strain gauge A is combined with the surface of the neck 343 .

In this preferred embodiment, except that the transverse grooves 11 of several casings 10 cooperate with the several projections 21 of the first external ring gear 20, there may also be only one transverse groove 11 to cooperate with the projections 21, which can also achieve The first external ring gear 20 is combined with the effect of being non-rotatable in the housing 10 . In addition, the cooperation between the clamping block 131 of the housing 10 and the concave portion 3425 of the fixing ring 342 can also be a concave-convex arrangement between the clamping block 131 and a concave portion 3425, and the fixing ring 342 of the torsion element 34 can also be fixed to the housing 10 The inner ring 13.

The above description is only a preferred feasible embodiment of the present invention, and all equivalent changes made by applying the description of the present invention and the scope of the patent application should be included in the scope of the patent of the present invention.

100: pedaling torque sensing device

10: shell

50: Transmission components

52: crankshaft

542: output terminal

Claims (8)

A pedaling torque sensing device for an electric bicycle, comprising: a housing; a first external gear, combined in the housing; a torque transmission component, including a second external gear and a torsion element, the second external gear One end of the torsion element is connected to the second outer ring gear, and the other end is fixed relative to the casing; a strain gauge is combined on the surface of the torsion element; a planetary gear structure is provided with a A planetary carrier, with several first planetary gears pivoted around one side of the planetary carrier, and several second planetary gears pivoted around the other side of the planetary carrier, the outer sides of the first planetary gears mesh with the first outer ring gear, the outer side of the second planetary gears meshes with the second outer ring gear; and a transmission assembly, including a crankshaft and an output hollow tube, the crankshaft passes through the torque transmission assembly and the planetary gear structure In the center, the crankshaft has a driving sun gear, the driving sun gear meshes with the inside of the second planetary gears, the output hollow tube is rotatably sleeved around the crankshaft, and one end of the output hollow tube There is an output sun gear, the output sun gear meshes with the inner sides of the first planetary gears, and the other end of the output hollow tube has an output end, which is used to drive the toothed disc of the electric bicycle to rotate; wherein the torsion element includes a A connecting ring, a fixing ring and a neck connected between the connecting ring and the fixing ring, the connecting ring is concentrically combined with the second outer ring gear, the fixing ring is fixed relative to the housing; the strain gauge is combined with The surface of the neck; the neck is a tube body and one end is connected to the inner periphery of the connecting ring, and the other end is connected to the inner periphery of the fixed ring, and the fixed ring is combined in the shell. The pedaling torque sensing device of an electric bicycle as described in claim 1, wherein a transmission gear is provided around the connecting ring, the transmission gear is coaxial with the second outer ring gear and the transmission gear meshes with the second outer ring gear for a full circle. ring gear. The pedaling torque sensing device of an electric bicycle according to Claim 1, wherein the housing has a tubular body, one side of the inner peripheral surface of the tubular body has at least one first keyway, and the other side has at least one second keyway, The outer peripheral surface of the first outer ring gear has at least one first key seat, the first key seat is opposite to the first key groove and a first key block is embedded in both, the outer peripheral surface of the fixed ring has at least one The second key seat is opposite to the second key groove and a second key block is embedded in both. The pedaling torque sensing device of an electric bicycle according to claim 3, wherein one end of the tubular body adjacent to the first keyway is screwed to a first end cap, and the first end cap has a first through hole and is embedded inside A first bearing, the crankshaft passes through the first through hole and passes through the first bearing; the other end of the tubular body adjacent to the second keyway is screwed to a second end cover, and the second end cover has a first Two through holes, the crank shaft passes through the second through holes. The pedaling torque sensing device of an electric bicycle as described in claim 4, wherein the inner side of the fixed ring has a bearing seat, and a second bearing is embedded in the bearing seat, and the crank shaft passes through the second bearing. The pedaling torque sensing device of an electric bicycle according to Claim 1, wherein the housing is a tubular body and the inner peripheral surface has at least one transverse groove, the transverse groove is a long groove extending in parallel to the axial direction of the crankshaft, the The outer peripheral surface of the first external ring gear has at least one protrusion, which is embedded in the transverse groove and fixed; the position of the fixed ring is matched with the end of the housing to form a ring whose inner diameter is smaller than that of other parts of the housing. Inner ring, the inner peripheral surface of the inner ring has at least one block, the outer peripheral surface of the fixed ring has at least one recess, and the block is inserted into the recess to fix the fixed ring. The pedaling torque sensing device of an electric bicycle according to any one of Claims 1 to 6, wherein the output end is a one-way bearing seat, and the one-way bearing seat is provided with a one-way bearing. The pedaling torque sensing device of an electric bicycle as described in any one of claims 1 to 6, wherein the reduction ratios of the first planetary gears, the first outer ring gear and the output sun gear are the same as those of the second The reduction ratios of the planetary gear, the second external ring gear and the driving sun gear are the same.

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