JP2013067206A - Human-powered drive force detection apparatus for electric bicycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a human-powered drive force detection apparatus for an electric bicycle where a general hanger part can be used, manufacturing cost can be lowered, and high reliability can be maintained.SOLUTION: The human-powered drive force detection apparatus 30 includes: an attaching member 31 laterally protruding from a hanger part 20 with a protrusion part extending in a stepped shape with a diameter greater than the hanger part 20, and including a small-diameter cylinder part 31a, an increased-diameter sidewall part 31b, and a large-diameter cylinder part 31c; a sensor support member 32 disposed in ring shape between an outer peripheral surface of a bearing 26 that rotatably supports a crankshaft 7a and an inner peripheral surface of the large-diameter cylinder part 31c of the attaching member 31, and including a resilient deformation part 32a with a radially reduced thickness compared with circumferentially adjacent part due to a partially cut-out outer periphery; and a distortion detection sensor 33 attached to the resilient deformation part 32a.

Description

  The present invention relates to a human power driving force detection device for an electric bicycle.

  A power storage device such as a battery; and an electric motor powered by the power storage device, wherein a human power driving force such as a pedaling force applied to a pedal is detected by a human power driving force detection device including a torque sensor, and the human power driving force In addition, there is already known an electric bicycle (also referred to as an electric assist bicycle) that can easily travel even on an uphill by applying an auxiliary driving force (assist force) of an electric motor corresponding to the human driving force.

  As an example of the method for detecting the manpower driving force, by utilizing the property that the crankshaft is twisted when the left and right pedals are depressed, the outer peripheral surface of the crankshaft and the cylindrical shaft to which the manpower driving force from the crankshaft is transmitted are used. A magnetostrictive torque sensor is known in which a magnetostrictive detection layer having magnetic anisotropy is formed on the outer peripheral surface, and a coil is disposed around the outer periphery of the magnetostrictive detection layer. This magnetostrictive torque sensor detects a twisted state of a crankshaft and a twisted state of a cylindrical shaft to which a manual driving force from the crankshaft is transmitted (Patent Document 1, etc.). Note that the crankshaft and the cylindrical shaft (referred to as a manpower transmission rotary shaft) are rotatably supported by bearings or the like.

  However, this magnetostrictive torque sensor requires processing of a magnetostriction generating portion and a coil, which requires a lot of manufacturing costs and difficult process management, and has a disadvantage that it takes a lot of labor and time.

  As another example of detecting a human driving force, there is a torque detection device for an electric bicycle disclosed in Patent Document 2. In bicycles including electric bicycles, a driving sprocket (also called front sprocket, front gear, or crank sprocket) as a manpower driven wheel is attached to a manpower transmission rotating shaft such as a crankshaft, and a slave attached to the rear wheel. A driving force transmission body such as a chain is stretched over a driven sprocket as a moving wheel body and the driving sprocket. Then, the manpower driving force is transmitted from the driving sprocket to the driven wheel body via the driving force transmitting body, and the rear wheel is rotated to travel. Therefore, even in an electric bicycle, a force that pulls a driving force transmission body such as a chain forward by the drive sprocket is generated during traveling, as in a general bicycle, and the crankshaft is elastically deformed backward by this reaction force.

  The torque detection device for an electric bicycle disclosed in Patent Document 2 applies the above structure of the bicycle. As shown in FIGS. 14, 15 (a), and 15 (b), a thin plate-like elastic deformation portion (support plate portion) 102 that receives and supports a force from which the crankshaft 101 is elastically deformed rearward from the crankshaft 101. A strain detection sensor (strain gauge) 103 for detecting the amount of elastic deformation is attached to the elastic deformation portion 102. In the structure shown in FIG. 14, the elastic deformation portion 102 and the strain detection sensor 103 are formed with a box-shaped holding frame portion 105 around a hanger portion 104 (also referred to as a bottom bracket). The elastic deformation part 102 is supported. In the structures shown in FIGS. 15A and 15B, the elastic deformation portion 102 is supported with the hanger portion 104 having a special shape.

  However, in the structure shown in FIGS. 14 and 15A and 15B, the structure itself is simple, but the holding frame part 105 is formed around the hanger part 104, or the hanger part 104 is formed in a special shape. Therefore, there is a difficulty that it is difficult to apply to a general bicycle.

  As a structure capable of coping with this difficulty, in Patent Document 3, as shown in FIGS. 16 to 19, an adapter member 151 having a shape extending from the end of the hanger portion 150 to the outer periphery, and the adapter member 151 are formed. A main body (sensor main body) 152 to be fitted inside the large-diameter portion 151a, and strain gauges 153, 154, 155, 156 are attached to a part of the sensor main body 152. It is disclosed. Here, as shown in FIGS. 16 to 18, the adapter member 151 includes an attachment portion 151 b that fits into the inner peripheral surface of the end portion of the hanger portion 150, a large diameter portion 151 a having a larger diameter than the hanger portion 150, and these And a flange portion 151c for connecting the two. As shown in FIG. 19, the sensor main body (main body) 152 includes a bearing 159 that rotatably supports an outer ring (outer portion) 152 a attached to the large-diameter portion 151 a of the adapter member 151 and the crankshaft 158. An inner ring (inner portion) 152b assembled to the outer periphery of the outer ring 152b, and connection portions 152c and 152d that connect the upper end portions and the lower end portions of the outer ring 152a and the inner ring 152b. And, the strain gauges 153 and 154 and the strain gauges 155 and 156, each of which is a set of two on the front surface and the back surface of the side surface of the connecting portion 152d that connects the lower ends of the outer ring 152a and the inner ring 152b, Along the respective side surfaces of the connecting portion 152d, they are attached in a posture orthogonal to each other.

  According to this structure, since the adapter member 151 and the sensor main body (main main body) 152 can be assembled to the general hanger 150, an electric bicycle having a general bicycle frame structure can be realized.

JP-A-9-95289 JP 2002-19683 A European Patent Publication No. 2248715

  However, in the structure disclosed in Patent Document 3, the path for supporting the human power driving force from the crankshaft 158 via the bearing 155 forms the outer ring 152a and the inner ring 152b, and the upper ends thereof are And the lower end portions are connected to each other and concentrated on the connection portions 152c and 152d having an extremely small cross-sectional area. Therefore, when the electric bicycle receives a large impact from the ground or the like, the connection portions 152c and 152d may be damaged or deformed. In this case, there is a possibility that the measurement accuracy of the human driving force is greatly reduced or the human driving force cannot be measured, and the reliability as an electric bicycle is also reduced.

  In addition, since four strain gauges 153 to 156 must be attached in a posture orthogonal to each other on each side surface on the front surface and the back surface on the side surface of the connecting portion 152d, the strain meters 153 to 156 in the production process. Assembling man-hours increases. In addition, since the strain gauges 153 to 156 must be positioned precisely during assembly, there is a disadvantage that much labor is required.

  The present invention solves the above-mentioned problems, and can use a general hanger part, can reduce the manufacturing cost, and at the same time, can be easily and quickly assembled, and has good reliability. An object of the present invention is to provide a human-powered driving force detection device for an electric bicycle capable of maintaining the above.

  In order to solve the above-described problems, the human-power driving force detection device for an electric bicycle according to the present invention protrudes laterally from the hanger part, and the protruding part spreads to a stepped shape having a diameter larger than that of the hanger part. A small-diameter cylindrical part attached to the inner periphery of the part, a large-diameter side wall extending radially from the end of the small-diameter cylindrical part, and a large-diameter cylindrical part extending in a cylindrical shape laterally from the large-diameter side wall. The mounting member has an annular shape between the outer peripheral surface of the bearing that rotatably supports the crankshaft and the inner peripheral surface of the large-diameter cylindrical portion of the mounting member, and a part of the outer periphery is notched A sensor support member having an elastically deformable portion that is shaped and thinner in the radial direction than a portion adjacent in the circumferential direction, and a strain detection sensor attached to the elastically deformable portion of the sensor support member. It is characterized by.

  According to this configuration, the mounting member having the large-diameter cylindrical portion is mounted so as to protrude laterally from the hanger portion, and between the outer peripheral surface of the bearing and the inner peripheral surface of the large-diameter cylindrical portion of the mounting member. Further, by disposing a sensor support member to which a strain detection sensor is attached, the sensor support member can be easily assembled while a hanger portion having the same shape as a general bicycle can be used. In addition, since the annular sensor support member is disposed inside the large-diameter cylindrical portion having a diameter larger than that of the hanger portion, the sensor support member can be used without any trouble even when the sensor support member has a diameter larger than that of the hanger portion. Can be assembled. Further, the sensor support member has an annular shape, and has a simple structure having an elastically deforming portion that is partially thin in the radial direction. Therefore, as the annular sensor support member, a member having a sufficient thickness in the radial direction including the elastic deformation portion and having a sufficient strength can be used. Even when receiving, the sensor support member is not damaged or deformed as the measurement accuracy of the sensor support member decreases. In addition, since the strain detection sensor is attached to the elastic deformation portion that is thin in the radial direction in the sensor support member, the number of strain detection sensors can be reduced, and the strain detection sensor can be attached to the elastic deformation portion. Assembly can be done easily and quickly.

  In addition, the electric bicycle to which the human power driving force detection device of the present invention is assembled is a human power driving wheel such as a driving sprocket in which a driving power transmitting body such as a chain for rotating the rear wheel rotates integrally with the crankshaft. The body and a driven wheel attached to the rear wheel, and is configured to be able to add an auxiliary driving force based on a human driving force by a pedaling force from a pedal, and the elastic deformation portion includes the driving force. The transmission body is elastically deformed by receiving a force that causes the crankshaft to be deformed rearward by a reaction force of a force pulling substantially forward by the human driving force.

  With this configuration, the manual driving force that is applied to the crankshaft and the like when the pedal is depressed is transmitted to the rear wheel via a driving force transmission body such as a chain, and the human driving force that actually contributes to running is well measured. can do.

  Further, the present invention is characterized in that the sensor support member is attached so that the posture of the sensor support member with respect to the crankshaft can be adjusted. With this configuration, the sensor support member to which the strain detection sensor is attached can be attached in a state adjusted to a good posture. Here, the elastic deformation portion and the strain detection sensor are rearwardly inclined obliquely downward from a line passing through the axis of the crankshaft in parallel with the direction in which the driving force transmission body is pulled forward by the human-powered driving wheel in a side view. It is preferable to be arranged at the position, and by arranging in this way, not only can the force for pulling the driving force transmission body substantially forward be measured better, but also the actual result caused by how the pedal is depressed, etc. In this case, the influence of a force that does not contribute to pulling the upper portion of the driving force transmission body can be suppressed to a very low level, and the reliability is improved.

  Further, according to the present invention, the mounting member includes a first mounting member having a small-diameter cylindrical portion, an enlarged side wall portion, and an outer peripheral portion of the large-diameter cylindrical portion, and an inner peripheral portion of the large-diameter cylindrical portion. It is comprised from the 2nd member for attachment which hold | maintains a sensor support member from outer periphery, It is characterized by the above-mentioned. With this configuration, when the shape of the hanger portion is different, it can be easily handled by changing the shape of the small-diameter cylindrical portion of the first mounting member. Further, even when the shape of the sensor support member is changed, it can be easily handled by changing the shape of the second mounting member.

  Further, according to the present invention, a plurality of concave and convex portions are formed on the surfaces of the first mounting member and the second mounting member that are fitted to each other, and by changing the fitting position of the concave and convex portions, the sensor support member The posture in the circumferential direction with respect to the crankshaft is adjustable. Accordingly, the circumferential posture of the sensor support member with respect to the crankshaft can be easily adjusted with a relatively simple configuration.

  Further, the present invention provides a mark that indicates a relative direction between a positioning portion that indicates an assembly position with respect to a sensor support member and a portion that is pulled by a manually driven wheel body in the drive force transmission body, on a mounting member to which the sensor support member is attached. And a portion. As a result, the sensor support member can be disposed at an appropriate position even when performing an inspection confirmation process in production, repair after sales, and the like, and good reliability can be maintained.

  In the present invention, three or more fixing members for fixing the sensor supporting member are provided, and at least two of these fixing members are arranged in a state in which the pressing force to the sensor supporting member can be adjusted. It is characterized by that. With this configuration, it is possible to easily adjust the sensitivity of the strain detection sensor by using the fixing member that fixes the sensor support member, and also compared to the case where a separate component for adjusting the sensitivity of the strain detection sensor is provided. The score can be reduced.

  Further, the present invention provides an exterior member that is sheathed by the first attachment member and the second attachment member, and holds the concave and convex portions of the first attachment member and the second attachment member in a fitted state. And a coupling portion for coupling the exterior member and the second attachment member, and an exterior member fixing portion for securing the exterior member to the first attachment member. According to this configuration, the first mounting is not performed unless the fixing of the exterior member and the first mounting member by the exterior member fixing portion is released and the coupling between the exterior member and the second mounting member by the coupling portion is not released. The concavo-convex portions of the working member and the second mounting member do not move in the separating direction, and the posture of the sensor support member to which the strain detection sensor is attached does not change. As a result, it is possible to satisfactorily prevent an unauthorized output variation of the strain detection sensor due to a change in the posture of the sensor support member, and it is possible to maintain good reliability as an electric bicycle.

  Further, the human power driving force detection device of the present invention is a strain detection sensor in which resin is injected into a portion corresponding to a shape part in which a part of the outer periphery is cut out while a wiring connected to the strain detection sensor is pulled out. Is waterproof. With this configuration, the strain detection sensor can be well waterproofed, and the reliability is improved.

  According to the present invention, a part of the outer periphery is notched inside the large-diameter cylindrical part that spreads in a stepped shape having a larger diameter than the hanger part, and is thinner in the radial direction than the part adjacent in the circumferential direction. Since the annular sensor support member having the elastically deformed portion is arranged, a general hanger portion can be used, and the annular sensor support member is sufficient including the elastically deformable portion. Use one with strength. Therefore, even when the electric bicycle is subjected to a large impact from the ground or the like, it is not damaged or deformed as the measurement accuracy of the sensor support member is lowered, and good reliability can be maintained. .

The whole side view of the electric bicycle provided with the manpower driving force detecting device concerning an embodiment of the invention Rear side view of the electric bicycle Perspective view of pedal, crank, hanger part and its vicinity of the electric bicycle Perspective view of human-powered driving force detection device of electric bicycle and its vicinity Rear view of Doujin force driving force detection device and its vicinity Doujin force driving force detection device and partially cutaway perspective view of the vicinity thereof Cross-sectional view of the human power driving force detection device and the vicinity thereof (however, the lower half is cut at a portion where a strain detection sensor is provided) Longitudinal cross-sectional view of the human power driving force detection device and its vicinity Disassembled perspective view of the human power driving force detection device and its vicinity Disassembled perspective view of the human power driving force detection device and its vicinity Longitudinal sectional view of the human power driving force detection device and the vicinity thereof with no second mounting member or sensor support member attached. Partial cutaway perspective view of the same human power driving force detection device and the vicinity thereof with no second mounting member or sensor support member attached. Side view for explaining arrangement positions of a sensor support member, a strain detection sensor and the like of the human power driving force detection device An exploded perspective view of a conventional human power driving force detection device (A) is a plane sectional view of a modification of the conventional human power driving force detection device, (b) is a side sectional view cut along line CC in FIG. 15 (a). Front sectional view of a crankshaft provided with another conventional human-power-driving-force detecting device and its vicinity Front sectional view of another conventional human power driving force detection device Exploded front sectional view of another conventional human power driving force detection device (A)-(c) is the left view, front view, and right view of the main body of the other conventional human-power-driving-force detection apparatus.

  Hereinafter, an electric bicycle and a human-powered driving force detection device for an electric bicycle according to embodiments of the present invention will be described with reference to the drawings. In the following description, the left and right refers to the left and right direction in a state where the user rides on the electric bicycle and faces forward (traveling direction).

  In FIG. 1 and FIG. 2, reference numeral 1 denotes an electric bicycle that includes a human power driving force detection device according to an embodiment of the present invention and is also referred to as an electric assist bicycle. As shown in FIGS. 1 and 2, this electric bicycle 1 includes a metal frame 2 including a head pipe 2a, a front fork 2b, a main pipe 2c, a standing pipe 2d, a chain stay 2e, a seat stay 2f, and the like, A front wheel 3 rotatably attached to the lower end of the fork 2b, a rear wheel 4 rotatably attached to the rear end of the chain stay 2e, a handle 5 that changes the direction of the front wheel 3, a saddle 6, and a crankshaft 7a and a crank arm 7b, a left and right pedal 8 to which a pedaling force as a manual driving force is applied, and an electric motor which generates an auxiliary driving force (assist force). 10, a control unit 11 as a control unit that performs various electrical controls including the electric motor 10, and power for driving the electric motor 10 A battery 12 made of a secondary battery, a hand operation unit (not shown) that is attached to the handle 5 and can be operated by a passenger, and a human-powered drive that is attached to rotate integrally with the crank 7 A drive sprocket (also called a front sprocket or front gear, a crank sprocket or a crank gear) 13 as a ring body and a driven sprocket as a driven wheel body attached to a hub (also called a rear hub) 9 of the rear wheel 4 (Also referred to as a rear sprocket, rear gear, or rear wheel gear) 14, a chain 15 as an endless driving force transmission member spanning the drive sprocket 13 and the driven sprocket 14, and the chain 15 and the like are covered from the side. A chain cover 21 and the like are provided.

  When a pedaling force, which is a manpower driving force, is applied to the pedal 8, the crank 7 rotates about the crankshaft 7a, and this manpower driving force is transmitted to the rear wheel via the drive sprocket 13, the chain 15, and the driven sprocket 14. 4 is rotated. In this embodiment, the electric motor 10 is built in a metal hub 16 (hereinafter also referred to as a front hub) disposed at the center of the front wheel 3. In addition, the battery 12 is an example of a capacitor, and a secondary battery is preferable. However, another example of the capacitor may be a capacitor.

  As shown in FIG. 2, the control unit (control unit) 11 includes a bottom bracket disposed at the center lower portion of the electric bicycle 1 so as to connect the rear end portion of the main pipe 2 c and the lower end portion of the standing pipe 2 d. A hanger 20 having a cylindrical shape (refer also to FIGS. 3 and 4) and a support bracket 19 disposed so as to connect the hanger 20 and the front end of the chain stay 2e are suspended. It is supported in the posture that was given. The control unit 11 includes a control board, a storage circuit, a unit case, and the like that control each component (including the electric motor 10) of the electric bicycle 1. Further, a battery 12 is placed above the support bracket 19, and the battery 12 is disposed in a space between the standing pipe 2 d and the rear wheel 4 while being also locked to the standing pipe 2 d. .

  As shown in FIGS. 3 to 7, the crankshaft 7 a is inserted through the hanger portion 20 in the lateral direction (horizontal direction on the left and right). As shown in FIGS. 6 and 7, a bearing 25 that rotatably supports the left side portion of the crankshaft 7 a is disposed inside the left end portion of the hanger portion 20. At the right end portion of the hanger portion 20, a human power driving force detection device 30 having a mounting member 31 and a sensor support member 32 to be described later is disposed, and inside the portion where the human power driving force detection device 30 is provided. A bearing 26 that rotatably supports the right side portion of the crankshaft 7a is disposed. In addition, 27A and 27B in FIG. 6 etc. are C-shaped ring bodies (what is called a C ring) which regulates the position of the bearing 26 in the crankshaft 7a. In addition, the drive sprocket 13 is attached to a location near the right side of the location where the manual driving force detection device 30 is provided on the crankshaft 7a.

  The human-power-driving-force detecting device 30 has a mounting member 31 that protrudes to the right from the hanger part 20 and has a protruding part that has a stepped shape with a diameter larger than that of the hanger part, and a right part of the crankshaft 7a. A sensor support member 32 annularly disposed between the outer peripheral surface of the bearing 26 to be supported and the inner peripheral surface of the large-diameter cylindrical portion 31c formed on the mounting member 31, and an elasticity formed on the sensor support member 32. The strain detection sensor 33 is attached by being attached to the deformable portion 32a and the like, and the exterior member 36 that covers and holds the large diameter portion of the attachment member 31 and the like.

  The mounting member 31 includes a small-diameter cylindrical portion 31a that is attached to the inner periphery of the right end portion of the hanger portion 20, a wide-diameter side wall portion 31b that extends radially from the end of the small-diameter cylindrical portion 31a, and this wide-diameter side wall portion 31b. A large-diameter cylindrical portion 31c that extends in a cylindrical shape on the right side. In this embodiment, the mounting member 31 includes a first mounting member 34 that is a so-called sensor case and a second mounting member 35 that is a so-called sensor cover. The first mounting member 34 is provided with a small-diameter cylindrical portion 31a, an enlarged side wall portion 31b, and an outer peripheral portion of the large-diameter cylindrical portion 31c (hereinafter referred to as the large-diameter cylindrical portion 34a of the first mounting member 34). It has been. On the other hand, the second mounting member 35 has an inner peripheral portion of the large-diameter cylindrical portion 31c of the mounting member 31 (hereinafter referred to as a cylindrical portion 35d of the second mounting member 35), and the sensor support member 32. A side wall covering portion 35a that is held from the outer periphery and extends in a disk shape in the radial direction from the right end portion of the cylindrical portion 35d is formed. The side wall covering portion 35a covers the sensor support member 32, the right side surface of the bearing 26, and the like. Yes.

  Screw portions 34d and 20a that are screwed to each other are formed on the outer peripheral surface of the small-diameter cylindrical portion 31a of the mounting member 31 (first mounting member 34) and the inner peripheral surface of the right end portion of the hanger portion 20 corresponding thereto. The small diameter cylindrical portion 31 a of the mounting member 31 is coupled by being screwed into the inner periphery of the right end portion of the hanger portion 20. Further, as shown in FIG. 8, a positioning fixing screw 37 that penetrates the hanger portion 20 and is screwed into the small-diameter cylindrical portion 31 a is provided at one location, and the mounting member 31 (first mounting member) is provided on the hanger portion 20. 34) is fixed so that the position of the mounting member 31 (first mounting member 34) does not shift. 7 shows a cut surface at a position where the strain detection sensor 33 and the elastic deformation portion 32a are located, as in the case shown in FIG. On the other hand, a cut surface such as the human power driving force detection device 30 in the lower half of FIG. 8 shows a cut surface when the human power driving force detection device 30 is cut so as to extend right below. In other words, in this embodiment, the positioning fixing screw 37 is provided directly under the hanger portion 20. However, the positioning position of the positioning fixing screw 37 may be provided at any position in the circumferential direction of the right end portion of the hanger portion 20.

  As shown in FIGS. 9 to 11, the inner peripheral surface of the large-diameter cylindrical portion 34 a of the first mounting member 34 and the outer peripheral surface of the cylindrical portion 35 d of the second mounting member 35 that are fitted to each other are provided. A large number (for example, several tens to several hundreds) of concave and convex portions 34b and 35b such as a triangular cross section or a rectangular cross section are formed. The first mounting member 34 is attached and fixed to the hanger portion 20 in advance, and the sensor support member 32 is attached and fixed inside the second mounting member 35. By changing the position and adjusting the relative position of the second mounting member 35 with respect to the first mounting member 34, the circumferential posture of the sensor support member 32 with respect to the crankshaft 7a can be adjusted. Further, as required, uneven portions 34b and 35b are provided on the inner peripheral surface of the large-diameter cylindrical portion 34a of the first mounting member 34 and the outer peripheral surface of the cylindrical portion 35d of the second mounting member 35. A sealing material 38 or the like for enhancing waterproofness may be provided at a location that is not. In addition, a mark portion 35c is formed at a predetermined position on the outer peripheral surface of the side wall covering portion 35a of the second mounting member 35 so that the sensor support member 32 is assembled at a predetermined position (details will be described later).

  As shown in FIGS. 9 and 10, the sensor support member 32 has an elastically deformable portion 32 a having a shape in which a part of the outer periphery is cut out and being thinner in the radial direction than a portion adjacent in the circumferential direction. . Further, in this embodiment, there is a shape having a gap between the upper portion and the lower portion in the rear portion of the bearing 26 and the upper portion and the lower portion in the rear portion of the inner peripheral surface of the sensor support member 32. As described above, the two notches 32 b are also formed in the inner peripheral portion of the sensor support member 32. Then, in the rear part of the bearing 26 and the rear part of the sensor support member 32, the bearing 26 and the sensor support member 32 abut only at the center part of the rear part, and the force from the crankshaft 7a is provided by the elastic deformation part 32a. It is comprised so that it may be favorably loaded to the location currently provided. In addition, a concave groove 32c for determining the position with the second mounting member 35 is formed in one place on the outer peripheral surface of the sensor support member 32, and correspondingly, the second mounting member 35 A rib 35e that fits into the groove 32c is formed at one location on the inner peripheral surface of the cylindrical portion 35d. That is, by assembling the sensor support member 32 to the second mounting member 35 in a state in which the concave groove 32c of the sensor support member 32 is fitted to the rib 35e of the second mounting member 35, the second mounting member 35 is attached to the second mounting member 35. The relative position of the sensor support member 32 is determined.

  A strain detection sensor 33 is attached to the elastic deformation portion 32a of the sensor support member 32 by being attached thereto. Therefore, the strain detection sensor 33 is disposed along a surface in contact with a line parallel to the axis of the crankshaft 7a. Here, although the elastic deformation portion 32a to which the strain detection sensor 33 is attached is thinner in the radial direction than other adjacent portions in the circumferential direction, the entire sensor support member 32 has a sufficient thickness in the radial direction. The elastic deformation portion 32a also has a sufficient thickness and sufficient strength. Further, the elastic deformation portion 32a of the sensor support member 32 and the strain detection sensor 33 are configured so that the crankshaft 7a is caused by the reaction force of the force that pulls the chain 15 substantially forward by the drive sprocket 13 by the manual driving force (stepping force) applied to the pedal 8. It is disposed at a position where it is elastically deformed by receiving a force to deform backward. Specifically, it is disposed at a position that is approximately behind the crankshaft 7a, but more specifically, is disposed at a position that is inclined slightly downward with respect to the crankshaft 7a. That is, as shown in FIG. 13, when viewed from the side, the drive sprocket 13 is parallel to the direction in which the upper portion of the chain 15 is pulled forward, and is inclined downward with respect to the line H passing through the axis 7b of the crankshaft 7a. More preferably, it is disposed at a rear position inclined downward by an angle α (for example, an inclination angle α is about 10 to 15 degrees). With this arrangement, not only can the force for pulling the chain 15 substantially forward be measured better, but also the force that does not actually contribute to pulling the upper part of the chain 15 due to the way the pedal 8 is depressed. Etc. can be minimized. For ease of understanding, FIG. 12 shows a case in which the direction in which the upper portion of the chain 15 is pulled is horizontal. However, the present invention is not limited to this. It is often inclined to.

  In this embodiment, the line of the mark portion 35 c formed on the side wall covering portion 35 a of the second mounting member 35 is orthogonal to the line of the upper portion of the chain 15 that is in contact with the upper end of the drive sprocket 13. It is described to be. However, the present invention is not limited to this, and a mark may be formed so that the position (posture) of the second mounting member 35 to which the sensor support member 32 is assembled can be recognized.

  Further, reference numeral 39 in FIGS. 6, 7, 9, 10, etc. denotes a plurality (this embodiment) having one end connected to the strain detection sensor 33 attached to the elastic deformation portion 32a of the sensor support member 32 (this embodiment). In this case, there are three wiring portions. The other ends of these wiring portions 39 are connected to the substrate of the control unit 11 via connection cords or the like not shown. An insertion hole 35g through which the wiring portion 39 passes is formed in the side wall covering portion 35a of the second mounting member 35. The wiring part 39 passes through the insertion hole 35g and exits from the side wall covering part 35a of the second mounting member 35, and then bends to the left from the radially outer side along the outer peripheral part of the exterior member 36 and exits to the outside. Has been. Further, the wiring cover 42 is attached so that rainwater, dust, and the like do not enter the location where the strain detection sensor 33 is provided from the outside through the location where the insertion hole 35g is provided. Further, the location where the strain detection sensor 33 is disposed, that is, the elastically deforming portion 32a of the sensor support member 32, the large-diameter cylindrical portion 34a and the enlarged-diameter side wall portion 31b of the first mounting member 34 facing this, and the second mounting portion. A space surrounded by the cylindrical portion 35d and the side wall covering portion 35a of the member 35 is filled with a waterproof resin 41 or the like and sealed. In this embodiment, a part of the inner surface of the cylindrical portion 35d is cut away so that the wiring portion 39 does not contact the cylindrical portion 35d of the second mounting member 35, but the present invention is not limited to this. .

  Furthermore, screw holes 35f for screwing fixing screws 43 as fixing members for fixing the sensor support member 32 to the second mounting member 35 are provided at three locations on the cylindrical portion 35d of the second mounting member 35. Is provided through the cylindrical portion 35d. Here, the fixing screw 43 is disposed in a state where the sensor support member 32 is shifted from the outer periphery in the circumferential direction by substantially the same angle, and is screwed to be embedded in the cylindrical portion 35d. In this embodiment, one screw hole 35f is formed through the rib 35e of the second mounting member 35, but the present invention is not limited to this.

  Further, the fixing screw 43 for fixing the sensor support member 32 is arranged in a state where the pressing force to the sensor support member 32 can be adjusted. And it is comprised so that the sensitivity adjustment of a distortion | strain detection sensor can also be easily performed by adjusting the press condition of each fixing screw 43. FIG.

  As shown in FIG. 11, the exterior member 36 includes a cylindrical portion 36a that covers the outer peripheral portion of the large-diameter cylindrical portion 34a of the first mounting member 34 and the side wall covering portion 35a of the second mounting member 35, and The side wall part 36b which covers the outer peripheral part in the diameter-expanded side wall part 31b of the 1 attachment member 34 from the side. In addition, a threaded portion 36c is formed at a position closer to the right side on the inner peripheral surface of the large-diameter cylindrical portion 34a of the exterior member 36. A screw portion 35h is also formed on the outer periphery of the side wall covering portion 35a of the second attachment member 35, and the second attachment member 35 and the exterior member 36 are configured to be screwed together. On the other hand, as shown in FIG. 9, FIG. 10, etc., no thread portion is formed on the outer periphery of the large-diameter cylindrical portion 34a of the first mounting member 34, and the first mounting member 34 and the exterior member 36 are Do not screw. However, as shown in FIGS. 8 and 11, the exterior member 36 is provided with a fixing screw 44 as an exterior member fixing portion for fixing to the first attachment member 34 at one location.

  The assembly work of the human power driving force detection device 30 is performed as follows. First, with the exterior member 36 inserted through the hanger part 20, the screw part 34 d of the first attachment member 34 is screwed into the screw part 20 a of the hanger part 20, and the first attachment member 34 is attached to the hanger part 20. . Further, a positioning fixing screw 37 penetrating the small-diameter cylindrical portion 31 a of the first attachment member 34 is screwed into the screw portion 20 a of the hanger portion 20 to fix the position of the first attachment member 34 with respect to the hanger portion 20.

  Next, the bearing 26 is assembled to the crankshaft 7a using the ring bodies 27A and 27B. Further, the sensor support member 32 having the strain detection sensor 33 attached to the elastic deformation portion 32a in advance is aligned so that the concave groove 32c of the sensor support member 32 fits into the rib 35e of the second attachment member 35. Then, the sensor support member 32 is fitted inside the cylindrical portion 35d of the second mounting member 35. Then, the fixing screws 43 provided at the three locations are screwed in to fix the sensor support member 32 to the second mounting member 35. At this time, the screw is adjusted by adjusting the pressing force of the fixing screw 43, thereby causing distortion. Adjustment is made so that the distortion is detected well from the detection sensor 33. If necessary, a waterproof resin 41 is filled around the strain detection sensor 33 with the seal cover 40 attached.

  Thereafter, the second mounting member 35 to which the sensor support member 32 and the wiring cover 42 are assembled is fitted to the first mounting member 34 fixed to the hanger portion 20 while the concave and convex portions 35b and 34b formed on each other are fitted together. Assemble. At this time, such a posture that the mark portion 35c of the second mounting member 35 is orthogonal to the upper portion of the chain 15 in contact with the upper end of the drive sprocket 13 so that the strain detection sensor 33 is in an appropriate position. Then, the second mounting member 35 is assembled.

  Further, the exterior mounting member 36 is assembled while being rotated so that the threaded portion 36c is screwed with the threaded portion 35h of the second mounting member 35, and the sensor support member 32 is housed in the first mounting member. 34 and the second mounting member 35 are brought into close contact with each other. Finally, the positioning fixing screw 44 of the exterior member 36 is screwed to fix the position of the exterior member 36. By doing in this way, the human-power-driving-force detection apparatus 30 can be assembled | attached favorably, arrange | positioning the sensor support member 32 which attached the distortion | strain detection sensor 33 in a favorable state.

  In the above configuration, when a person steps on the pedal 8, the manpower driving force by the pedaling force at this time is transmitted to the crankshaft 7a and the drive sprocket 13 via the crank arm 7b. Then, the driving sprocket 13 changes the force to pull the chain 15 forward and transmits it to the driven sprocket 14 of the rear wheel 4. Further, the force to the driven sprocket 14 is transmitted and the rear wheel 4 is rotated. At this time, the drive sprocket 13 and the crankshaft 7a tend to elastically deform backward as a reaction force of the force that pulls the chain 15 forward by the drive sprocket 13, and this force is received by the bearings 25 and 26. At this time, a larger reaction force is received by the right bearing 26 to which the drive sprocket 13 is attached in the crankshaft 7a. This force causes the elastic deformation portion 32a formed at the rear portion of the sensor support member 32 disposed between the bearing 26 and the hanger portion 20 to be deformed. A certain torque) can be detected by the strain detection sensor 33. In this case, as described above, the strain detection sensor 33 is disposed at a position on the rear side of the annular sensor support member 32 that is inclined slightly lower than the position on the rear side of the crankshaft 7a. Thus, the upper portion of the chain 15 that actually acts as the driving force for rotating the rear wheel is reduced while suppressing adverse effects such as the force that does not contribute to pulling the upper portion of the chain 15 due to the way the pedal 8 is depressed. The pulling manpower driving force can be measured well.

  Here, according to the above configuration, the mounting member 31 (consisting of the first mounting member 34 and the second mounting member 35) having the large-diameter cylindrical portion 31 c protrudes laterally from the hanger portion 20. The hanger portion 20 having the same shape as a general bicycle is provided by disposing the sensor support member 32 to which the strain detection sensor 33 is attached between the large diameter cylindrical portion 31c of the attachment member 31 and the bearing 26. The sensor support member 32 can be easily assembled with a very simple configuration while using.

  Further, the sensor support member 32 has an annular shape, and has an extremely simple structure having a part of the elastic deformation portion 32a that is thin in the radial direction. That is, as disclosed in Patent Document 3, the upper ends and the lower ends of the outer ring 152a and the inner ring 152b are connected to each other so as to concentrate on the connecting portions 156 and 157 having an extremely small cross-sectional area. The structure is not complicated and has a portion with reduced strength.

  Accordingly, as the annular sensor support member 32, a relatively thick and sufficient strength including the elastic deformation portion 32a can be easily used. As a result, even when the electric bicycle 1 is subjected to a large impact from the ground or the like, the sensor support member 32 is not damaged or deformed so that the measurement accuracy of the sensor support member 32 is lowered. Sex can be maintained.

  Further, according to the above configuration, since the strain detection sensor 33 is attached to the elastic deformation portion 32a that is thin in the radial direction in the sensor support member 32, the number of strain detection sensors 33 is small (one or two). ), And the assembly operation of the strain detection sensor 33 to the elastically deforming portion 32a can be performed easily and quickly.

  Moreover, according to the said structure, the attachment member 31 is attached to the hanger part 20, the 1st attachment member 34 which has the outer peripheral part (large diameter cylinder part 34a) of the large diameter cylinder part 31c, and a large diameter cylinder part It comprises a second mounting member 35 that forms the inner peripheral portion (cylinder portion 35d) of 31c and holds the sensor support member 32 from the outer periphery. Thereby, the sensor support member 32 to which the strain detection sensor 33 is attached is adjusted to a good posture by using the uneven portions 34b and 35b provided on the first attachment member 34 and the second attachment member 35. Can be installed in the state. Moreover, even when the diameter dimensions of the hanger part 20 differ, it can respond easily by changing the shape of the small diameter cylindrical part 31a of the member 34 for 1st attachment. Further, even when the diameter dimension of the sensor support member 32 is changed, it can be easily handled by changing the shape of the cylindrical portion 35d of the second attachment member 35. Further, the sensor support member 32 can be favorably held from both sides by the enlarged diameter side wall portion 31 b of the first mounting member 34 and the side wall cover portion 35 a of the second mounting member 35.

  Further, the mounting member 31 (second mounting member 35 in this embodiment) to which the sensor support member 32 is mounted has a rib 35e as a positioning portion indicating the mounting position with respect to the sensor support member 32, and the chain 15 is mounted. Since the mark portion 35c indicating the position is formed, the sensor support member 32 can be disposed at a suitable position even when performing a production inspection check process, repair after sales, or the like, and has good reliability. Can be maintained. In the above-described embodiment, the positioning portion indicating the assembly position of the attachment member 31 (second attachment member 35) with respect to the sensor support member 32 is formed by the rib 35e or the concave groove 32c. However, the present invention is not limited to this as long as the relative position can be determined.

  Further, according to the above configuration, the fixing screws 43 as the fixing members for fixing the sensor support member 32 are provided and the pressing force to the sensor support member 32 can be adjusted by the fixing screws 43. 43, the sensitivity adjustment of the strain detection sensor 33 can be easily performed. In addition, since the number of parts can be reduced as compared with the case where parts for adjusting sensitivity are separately provided, the manufacturing cost can be reduced. In addition, by providing three or more fixing screws 43 as fixing members, it is possible to arbitrarily set the pressing force to the sensor support member 32 to which the strain detection sensor 33 is attached in the circumferential direction. Two or more members that can adjust the pressing force to the sensor support member 32 may be provided. Further, four or more fixing screws 43 may be provided.

  Moreover, in the said structure, the exterior member 36 which is exteriorly covered by the 1st attachment member 34 and the 2nd attachment member 35, and hold | maintains in the state which each uneven | corrugated | grooved part 34b, 35b of these members fitted, A screw portion 36c and a screw portion 35h as a connecting portion for connecting the exterior member 36 and the second attachment member 35, and a fixing screw 44 as an exterior member fixing portion for fixing the exterior member 36 to the first attachment member 34. And are provided. According to this configuration, the fixing screw 44 is loosened and the screw portion 36c of the exterior member 36 is not detached from the screw portion 35h of the second mounting member 35 from the state where the human-power-driving force detection device 30 is completely assembled. The relative positions of the first mounting member 34 and the second mounting member 35 are not shifted, and the concavo-convex portions 34b and 35b are not separated from each other. In other words, unless the exterior member 36 is detached from the first mounting member 34 and the second mounting member 35, unauthorized output fluctuation of the strain detection sensor 33 due to a change in the posture of the sensor support member 32 to which the strain detection sensor 33 is mounted. Can be prevented, and good reliability as an electric bicycle can be maintained.

  Further, in the above configuration, the wiring portion 39 connected to the strain detection sensor 33 using the elastic deformation portion 32a of the sensor support member 32 to which the strain detection sensor is attached, that is, the cutout portion of the sensor support member 32. Is pulled out from the side wall covering portion 35 a of the second mounting member 35. Then, a waterproof resin 41 is injected into a portion corresponding to the cutout portion of the sensor support member 32, and the connection portion between the strain detection sensor 33 and the wiring portion 39 of the strain detection sensor 33 gets wet with water that has entered from the outside. Prevents dirt and dirt. As a result, the strain detection sensor 33 is well protected and good reliability can be maintained. Further, the signal from the strain detection sensor 33 can be extracted to the outside while using the general hanger 20.

  The present invention can be suitably applied to an electric bicycle that actually travels, but is not limited thereto, and can also be applied to a fixed electric bicycle for training installed in a sports gym or the like.

1 Electric Bicycle 2 Frame 3 Front Wheel 4 Rear Wheel 5 Handle 7 Crank 7a Crankshaft 7b Crank Arm 8 Pedal 9 Hub (Rear Hub)
10 Electric Motor 11 Control Unit 12 Battery (Accumulator)
13 Drive sprocket (man-powered wheel)
14 Driven sprocket (driven wheel)
15 Chain (driving force transmission body)
16 Hub (front hub)
20 Hanger part 20a Screw part 26 Bearing 30 Human power driving force detection device 31 Mounting member 31a Small diameter cylindrical part 31b Wide diameter side wall part 31c Large diameter cylindrical part 32 Sensor support member 32a Elastic deformation part 32b Notch part 32c Concave groove 33 Strain detection Sensor 34 First mounting member 34a Large diameter cylindrical portion 34b Uneven portion 34c Screw portion 34d Screw portion 35 Second mounting member 35a Side wall covering portion 35b Uneven portion 35c Mark portion 35d Tubular portion 35e Rib 35g Insertion hole 35h Screw portion ( Joint)
36 exterior member 36a cylindrical part 36b side wall part 36c screw part (joint part)
37 Positioning fixing screw 39 Wiring part 42 Wiring cover 41 Resin 43 Fixing screw (fixing member)
44 Fixing screw (exterior member fixing part)

Further, the present invention is characterized in that the sensor support member is attached so that the posture of the sensor support member with respect to the crankshaft can be adjusted. With this configuration, the sensor support member to which the strain detection sensor is attached can be attached in a state adjusted to a good posture. Here, the elastic deformation part and the strain detection sensor, similar side view, rear of the driving force transmitting member is inclined obliquely downward from a line passing through an axis parallel crank axis direction pulling forward by human-driven wheel member It is preferable to be arranged at the position, and by arranging in this way, not only can the force for pulling the driving force transmission body substantially forward be measured better, but also the actual result caused by how the pedal is depressed, etc. In this case, the influence of a force that does not contribute to pulling the upper portion of the driving force transmission body can be suppressed to a very low level, and the reliability is improved.

Claims (10)

A narrow cylindrical part attached to the inner periphery of the end of the hanger part, and a diameter projecting from the end part of the small diameter cylindrical part. A mounting member having an enlarged side wall portion extending in the direction and a large diameter cylindrical portion extending in a cylindrical shape to the side from the enlarged side wall portion;
It is annularly arranged between the outer peripheral surface of the bearing that rotatably supports the crankshaft and the inner peripheral surface of the large-diameter cylindrical portion of the mounting member, and a part of the outer periphery is cut out in the circumferential direction. A sensor support member having an elastically deformable portion that is thinner in the radial direction than the portion adjacent to
An apparatus for detecting a human driving force of an electric bicycle, comprising: a strain detection sensor attached to an elastic deformation portion of the sensor support member. The electric bicycle to which the human driving force detection device is assembled has a driving force transmission body such as a chain for rotationally driving the rear wheel, a manpower driving wheel body such as a driving sprocket that rotates integrally with the crankshaft, and a rear wheel. It is constructed so as to be able to add an auxiliary driving force based on the human driving force by the pedaling force from the pedal,
The elastic deformation portion is elastically deformed by receiving a force that causes the crankshaft to be deformed rearward by a reaction force of a force pulling the driving force transmission body substantially forward by the human driving force. The human-power driving force detection device for an electric bicycle according to 1.   2. The human power driving force detection device for an electric bicycle according to claim 1, wherein the sensor support member is attached so as to be capable of adjusting a circumferential posture of the sensor support member with respect to the crankshaft.   When viewed from the side, the elastically deforming part and the strain detection sensor are arranged at a rear position inclined obliquely downward from a line passing through the axis of the crankshaft parallel to the direction in which the driving force transmitting body is pulled forward by the human-powered driving wheel. The human power driving force detecting device for an electric bicycle according to claim 1, wherein the device is provided.   The mounting member includes a first mounting member having a thin cylindrical portion, an enlarged side wall portion, and an outer peripheral portion of the large cylindrical portion, and an inner peripheral portion of the large cylindrical portion, and the sensor support member from the outer periphery. 2. The human-power-driving-force detecting device for an electric bicycle according to claim 1, comprising a second mounting member to be held.   A plurality of concave and convex portions are formed on the surfaces of the first mounting member and the second mounting member that are fitted to each other. By changing the fitting position of the concave and convex portions, the sensor support member in the circumferential direction with respect to the crankshaft 5. The human-power driving force detection device for an electric bicycle according to claim 4, wherein the posture is adjustable.   The mounting member to which the sensor support member is attached is provided with a positioning portion that indicates an assembly position with respect to the sensor support member, and a mark portion that indicates a relative direction between the driving force transmitting body and the portion that is pulled by the manpower driven wheel. The human-power driving force detection device for an electric bicycle according to claim 1.   Three or more fixing members for fixing the sensor supporting member are provided, and at least two of these fixing members are arranged in a state in which the pressing force to the sensor supporting member can be adjusted. Item 8. The human-powered driving force detection device for an electric bicycle according to any one of Items 1 to 7.   An exterior member is provided that is sheathed by the first attachment member and the second attachment member, and holds the concave and convex portions of the first attachment member and the second attachment member in a fitted state. The human-powered drive for an electric bicycle according to claim 6, further comprising: a coupling portion that couples the second mounting member; and an exterior member fixing portion that fixes an exterior member to the first mounting member. Force detection device.   The strain detection sensor is waterproofed by injecting a resin into a portion corresponding to a shape part in which a part of the outer periphery is cut out in a state where the wiring connected to the strain detection sensor is pulled out. The human-power-driving-force detection apparatus of the electric bicycle of any one of 1-9.

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