Electrically assisted bicycles

Abstract

To provide a power-assisted bicycle which can be relatively easily attached to a normal bicycle, in which a motor can be easily repaired and inspected, and further, which can easily keep weight balance of front and rear wheels evenly, and can reduce a stepping-in force by a foot particularly when starting travel.SOLUTION: A power-assisted bicycle comprises: a power generator 1 in which a sprocket S for electric power generation engaging with a chain CH stretched between a main sprocket S1 mounted on a crank shaft 100A and a rear sprocket S2 on a rear wheel side is mounted on a rotary shaft for power generation, and which is firmly provided on a part of a frame F of a bicycle between front and rear wheels; a capacitor 2 which stores electric power generated from the power generator 1; a motor 3 with regenerative function that is driven by electric power supplied from the power generator 1, and applies a rotating force to the crank shaft 100A; speed detection means which detects a travel speed of a bicycle 100; a control part 51 which controls an amount of power supply from the capacitor 2 to the motor 3 according to the travel speed of the bicycle 100 detected by the speed detection means 4; and a storage box 6 which is installed in a space between bicycle frames between the front and rear wheels, and accommodates the capacitor 2 and control means.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] This invention relates to electric bicycles such as two-wheeled or three-wheeled vehicles, and more particularly to an electrically assisted bicycle in which a capacitor is charged with electromotive force generated by the movement of the bicycle, and a motor is driven by the power supplied from the capacitor, thereby assisting the pedaling force of the bicycle with the rotational driving force of the motor. [Background technology]

[0002] In recent years, many electrically assisted bicycles have been developed and are becoming popular. These electrically assisted bicycles are generally configured with a direct drive system, with a motor directly connected to the rotating shaft of either the front or rear wheel. In electrically assisted bicycles with this configuration, the rotational driving force of the motor assists the pedaling force of the foot when pedaling, making the bicycle easier to ride.

[0003] Furthermore, among these electrically assisted bicycles, there are also proposed bicycles that use an amplifier circuit device that rotates based on the magnetic force between permanent magnets, as described in Patent Document 1. The bicycle described in Patent Document 1 has a power generating device mounted on the pedal side, and a power generating unit inside the power generating device, and the electricity generated by the power generating unit is stored in a secondary battery separately provided inside the power generating device.

[0004] However, the bicycle described in Patent Document 1 is configured to rotate the pedal shaft using power from a secondary battery, but it does not have a rotation transmission mechanism or torque interlocking mechanism to provide torque to the crank shaft even when the pedal shaft rotates. As a result, no matter how much the pedal shaft is rotated, it is not possible to transmit the rotation of the crank shaft, and ultimately the torque to the sprocket on the rear wheel via the sprocket mounted coaxially with the crank shaft. In other words, it does not have an electric assist function for the bicycle.

[0005] Furthermore, Patent Document 2 also discloses a magnetic bicycle. This magnetic bicycle has a generator on the front wheel side and a motor on the rear wheel side. This magnetic bicycle uses a timing belt to rotate a full induction magnet rotating wheel, and when the motor starts to rotate, a strong repulsive force is generated when the large-diameter electromagnet wheel in the center approaches a permanent magnet, with the same pole faces facing each other. This force is used directly to turn the rear wheel, and the bicycle is designed to be able to ride without the need to pedal a few seconds after the initial pedaling.

[0006] Furthermore, an electrically assisted bicycle is also disclosed in Patent Document 3. This electrically assisted bicycle is configured to include an alternator that receives rotational force from the crankshaft to generate electricity, a secondary battery that stores the direct current output from the alternator, and a drive hub motor provided on the front wheel. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-128265 [Patent Document 2] Japanese Patent Application Laid-Open No. 2011-160644 [Patent Document 3] Patent Application No. 2020-30079 Summary of the Invention [Problem to be solved by the invention]

[0008] Incidentally, the electrically assisted bicycle described in Patent Document 2 has a main magnet fixed to the main shaft, which is the axis of rotation of the rear wheel, in a complex manner, becoming one with the main shaft. The motor is also mechanically integrated with the main shaft. This makes it difficult to assemble or remove the main magnet, for example, and also makes repairing or inspecting the motor troublesome. Furthermore, with an electrically assisted bicycle configured in this way, the weight is concentrated on the rear, resulting in an extremely unbalanced weight distribution between the front and rear wheels, which is undesirable in terms of safety and riding stability, for example, when descending slopes.

[0009] Furthermore, in the electrically assisted bicycle described in Patent Document 3, the motor is integrated with the rotary shaft of the front wheel, making it troublesome and cumbersome to remove and inspect the motor for repairs, for example.

[0010] Furthermore, in Patent Document 3, the alternator is not directly attached to the frame, but rather protrudes outward from the frame near the crankshaft to which the pedals are attached. This means that when a cyclist pedals, their calves and other parts of their feet come into contact with or get in the way of the alternator, making operation cumbersome. Furthermore, because the alternator protrudes to one side of the bicycle, it can cause imbalance between the left and right sides, potentially compromising riding safety.

[0011] Furthermore, in the electrically assisted bicycle described in Patent Document 3, the weight is concentrated on the front side, resulting in poor weight balance between the front and rear wheels, which is undesirable in terms of riding stability.

[0012] The object of this invention is to provide an electrically assisted bicycle that is relatively easy to install on a normal bicycle, that is easy to repair and inspect the motor, that is easy to achieve an equal weight balance between the front and rear wheels, and that reduces the amount of force required to pedal, especially when starting to ride. [Means for solving the problem]

[0013] The electrically assisted bicycle of this invention is equipped with a speed detector that detects the traveling speed of the bicycle. knowledgea generator fixed to a part of the frame between the front and rear wheels and equipped with a power generating sprocket that meshes with a chain that is stretched between a main sprocket mounted on the crankshaft to which the pedals are attached and a rear sprocket mounted on the rear wheel hub axle; storage means that takes in and stores the electricity generated by the generator; a motor fixed to a part of the frame between the front and rear wheels and driven by electricity supplied from the generator or storage means, that applies a rotational force to the crankshaft according to the traveling speed of the bicycle detected by the speed detection means; control means that controls the amount of electricity supplied from the storage means to the motor according to the traveling speed of the bicycle; and a storage box that is installed in the gap between the frames between the front and rear wheels and that houses at least the storage means and the control means.

[0014] In addition, the electrically assisted bicycle of the present invention is equipped with a torque detector that detects the torque generated when the foot force on the pedal acts on the crankshaft of the main sprocket, and the control means that detects the change in torque controls the capacitor according to the amount of change in torque, thereby increasing or decreasing the amount of power supplied from the capacitor to the motor.

[0015] In the electrically assisted bicycle of the present invention, the motor and the generator are arranged such that the output shaft of the motor and the rotating shaft of the generator are disposed in close proximity to each other.

[0016] In addition, the electrically assisted bicycle of this invention is equipped with an electromagnetic clutch between the output shaft of the motor and the crankshaft of the main sprocket to connect and disconnect the rotational force from the motor, and is configured so that when the rotation speed of the crankshaft of the main sprocket or the speed of the bicycle exceeds a certain value, the clutch is activated under control of the control means to interrupt the transmission of the rotational force from the motor to the crankshaft of the main sprocket.

[0017] In addition, in the electrically assisted bicycle of this invention, the motor has a regenerative function, and the control means is configured so that when the bicycle speed input from the speed detection means exceeds a certain value, the power supply from the generator or the storage means to the motor is stopped, and the regenerative power of the motor generated when the rotational force of the main sprocket is transmitted to the motor is output to the storage means.

[0018] The generator and / or motor has a unique magnetic flux distribution formed by the formation of a magnetic circuit due to the unique arrangement and alignment of permanent magnets provided inside.

[0019] The arrangement and alignment of the permanent magnets of the generator and / or motor is configured to have a Halbach array magnetic field.

[0020] In the electrically assisted bicycle of the present invention, at least the generator has a brushless and coreless structure.

[0021] In addition, the electrically assisted bicycle of this invention is equipped with an operation panel that is installed at the front of the bicycle body and has a switch that can switch between supplying and halting power from the generator to the storage means, and supplying and halting power from the storage means to the motor, depending on the usage status of the bicycle. [Effects of the Invention]

[0022] According to the electrically assisted bicycle of the present invention, a speed detector detects the traveling speed of the bicycle. knowledgea generator fixed to a portion of the frame between the front and rear wheels and equipped with a power-generating sprocket that meshes with a chain that is tensioned between a main sprocket mounted on a crankshaft to which the pedals are attached and a rear sprocket mounted on the rear wheel hub axle, power storage means that takes in and stores power generated by the generator, a motor fixed to a portion of the frame between the front and rear wheels and driven by power supplied from the generator or power storage means that applies a rotational force to the crankshaft according to the traveling speed of the bicycle detected by the speed detection means, control means that controls the amount of power supplied from the power storage means to the motor according to the traveling speed of the bicycle, and a storage box installed in the gap between the front and rear wheels and that houses at least the power storage means and the control means. Furthermore, the electrically assisted bicycle of the present invention has a structure in which parts that are prone to breakdowns or require frequent maintenance, such as a generator, power storage means, and motor, are mounted on the axles around which the front and rear wheels rotate. Success Since it is not a nut, it can be easily attached and detached for repair, inspection, replacement, etc. [Brief explanation of the drawings]

[0023] [Figure 1] 1 is a front view showing an electrically assisted bicycle (two-wheeled or three-wheeled vehicle) according to an embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view taken along line II-II in FIG. [Figure 3] FIG. 2 is an enlarged view of the main part showing the arrangement of the generator, motor, etc. shown in A of FIG. [Figure 4] 4A is an explanatory diagram showing a generator used in an electrically assisted bicycle according to one embodiment of the present invention and its installation state, and FIG. 4B is a cross-sectional view taken along line IVB-IVB. [Figure 5] 1 is an explanatory diagram showing a method of attaching a motor to a bicycle frame according to an embodiment of the present invention. [Figure 6] (A) shows the mounting position of a speed detector according to one embodiment of the present invention. [Figure 7] 1 is a block diagram showing an example of the configuration of an electrically assisted bicycle according to an embodiment of the present invention; [Figure 8] 4 is a flowchart showing the control of the motor of the electrically assisted bicycle according to one embodiment of the present invention. [Figure 9] 5 is a flowchart showing the control of the generator of the electrically assisted bicycle according to one embodiment of the present invention. [Figure 10] FIG. 10 is an explanatory diagram showing a selection menu that is a setting mode of an electrically assisted bicycle according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] The gist of this invention relates to an electrically assisted bicycle comprising: a generator fixed to a part of the frame between the front and rear wheels, the generator sprocket being mounted coaxially with the rotating shaft for generating electricity and meshing with a chain stretched between a main sprocket mounted on a crankshaft to which the pedals are attached and a rear sprocket mounted on the rear wheel hub shaft; electricity storage means that takes in and stores electricity generated by the generator; a motor fixed to a part of the frame between the front and rear wheels, driven by electricity supplied from the generator, and applying a rotational force to the crankshaft in accordance with the traveling speed of the bicycle; speed detection means that detects the traveling speed of the bicycle; control means that controls the amount of electricity supplied from the electricity storage means to the motor in accordance with the traveling speed of the bicycle detected by the speed detection means; and a storage box installed in the gap between the frames between the front and rear wheels and that houses at least the electricity storage means.

[0025] Next, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. <Electric assist bicycle according to an embodiment of the present invention> (Configuration of an electric assist bicycle) Fig. 1 is a front view of an electrically assisted bicycle 100 (hereinafter simply referred to as "bicycle 100") according to one embodiment of the present invention. This electrically assisted bicycle includes the same basic components as a typical bicycle, namely, a frame F that forms the framework of bicycle 100, a front wheel W1 and a rear wheel W2, a chain CH stretched between a sprocket on the rear wheel W2 side (hereinafter referred to as the "rear sprocket S2") and a main sprocket S1 fixed coaxially with a crankshaft 100A, a saddle SD, a handlebar H, a lamp L, and a brake (not shown). Furthermore, as shown in Fig. 6, the electrically assisted bicycle also includes a generator 1, a power storage device 2 (hereinafter referred to as the "power storage device 2"), a motor 3 with a regenerative function, a speed detection device 4, a control device 5, a housing box 6 that houses the power storage device 2 and the control device 5, a torque detector 7, an electromagnetic clutch 8, an operation panel 9, and first to third electromagnetic switches SW1 to SW3.

[0026] In Figure 1, the frame F of this embodiment comprises a front tube F1 for mounting and supporting the front wheel W1 and handlebars H, a seat tube F2 for supporting the saddle SD and having a crankshaft 100A which serves as the center of rotation of the crank on which the pedals P are mounted, a top tube F3 and a down tube F4 which connect the front tube F1 and the seat tube F2, and a rear top tube F5 and a rear down tube F6 which support the rear wheel W2 and are connected to the seat tube F2.

[0027] The generator 1 is connected to a main sprocket S1 mounted on a crankshaft 100A, which is the main shaft of a crank C equipped with pedals P, and a rear wheel W. 2A sprocket S dedicated to the generator, which meshes with a chain CH stretched between a rear sprocket S2 mounted on the hub axle 100C (hereinafter referred to as the "rear hub axle 100C") and the rear sprocket S, is fixedly mounted on a flanged large shaft 1E that is attached coaxially and integrally with the rotating shaft 1A of the generator 1. As shown in Figures 2 to 4, the generator 1 of this embodiment is cantilevered on a fixed shaft 1D that is fixed to a bracket 1C of a mounting plate 1B that is screwed onto the seat tube F2 that forms part of the frame F of the bicycle, and is fixed integrally to the seat tube F2 side.

[0028] In particular, the generator 1 of this embodiment is a magneto generator as shown in FIG. 4(B), i.e., a brushless and coreless synchronous generator configured with a Halbach array permanent magnet MG (described later) on the rotor 1R side and coil windings (not shown) on the stator 1S side. Because the generator 1 has a simple brushless structure, it is less prone to malfunction and easier to maintain. The output of the generator 1 is connected to a rectifier 11 provided on the board of the control means 5 shown in FIG. 7, and alternating power (alternating current) from the coil windings on the stator 1S side is sent to the rectifier 11 shown in FIG. 7.

[0029] Furthermore, the generator used in the present invention is hardly subjected to resistance known as cogging torque, as described in Patent No. 4782303, for example, and generates stable electromotive force efficiently, so it can demonstrate sufficient power generation capacity even when generating electricity using a power source at the start of bicycle riding at low speeds.

[0030] The capacitor 2 takes in and stores the power generated by the generator 1, and as shown in FIG. 7, its input is connected to the output of the rectifier 11 via the third electromagnetic switch SW3, and its output is connected to the input of the motor 3 via the first electromagnetic switch SW1.

[0031] The capacitor 2 is also connected to the control means 5 so that the control means 5 can constantly detect the amount of electricity stored in the capacitor 2. Therefore, the first electromagnetic switch SW1 is opened and closed by a control signal from the control means 5, so that power supply from the capacitor 2 to the motor 3 can be switched on and off as appropriate. Note that although a lithium-ion battery is used for the capacitor 2 in this embodiment, other appropriate power storage means such as a capacitor or a supercapacitor can also be used.

[0032] The motor 3 supplements and supplements the propulsive force of the bicycle when necessary, in addition to the propulsive force generated by pedaling force on the pedals P. The motor 3 of this embodiment is configured so that the rotor (not shown) has a Halbach array magnetic field, similar to the rotor 1R of the generator 1, and is capable of generating a large torque.

[0033] Here, we will briefly explain this Halbach array. It is generally known that the energy conversion efficiency of motors and generators depends greatly on the strength of the magnetic force (strength of the magnetic field). Taking this into consideration, a group of magnets with a unique magnetic pole arrangement (i.e., a Halbach array) has already been discovered. In other words, this Halbach array is a configuration in which adjacent magnets are combined with their north and south poles rotated by 90 degrees, and multiple groups of these combined magnets are continuously and cyclically arranged. A particularly notable feature is the ability to concentrate the magnetic field on one side of the magnet, thereby strengthening the magnetic force. The motor 3 of this embodiment is equipped with a rotor equipped with a group of magnets with this Halbach array.

[0034] The motor 3 of this embodiment also has an output shaft 3A that is driven to rotate by electric power supplied appropriately from the generator 1 under the control of the control means 5. That is, as shown in Figures 2 and 3, the motor 3 is configured so that the rotational force of the motor gear 3B attached to the output shaft 3A is transmitted via an electromagnetic clutch 8 to an assist gear 3C (described below), thereby applying a rotational force to the crankshaft 100A that corresponds to the traveling speed of the bicycle 100.

[0035] As shown in FIGS. 2 and 3, the assist gear 3C is connected to the main sprocket S1 via a multi-leg plate LFP having an overall substantially star-shaped configuration that is fixed to the back side of the main sprocket S1. S1 The multi-leg plate LFP is fixed to the main sprocket S1 side, and rotates integrally with the main sprocket S1 at the same angular velocity. The multi-leg plate LFP is arranged and sized so that each of its equiangularly radially protruding legs overlaps the inner periphery of the roughly doughnut-shaped main sprocket S1, and is screwed to the main sprocket S1 at these legs. The assist gear 3C is smaller than the outer shape of the multi-leg plate LFP, but has outer dimensions that allow it to mesh exactly with the motor gear 3B that is fixed coaxially to the output shaft 3A of the motor 3. The assist gear 3C always rotates in the same direction as the main sprocket S1, but the motor gear 3B that meshes with the assist gear 3C always rotates in the opposite direction to the assist gear 3C.

[0036] The pedals P are used to pedal the bicycle by placing the feet on them. The cranks C to which the pedals P are attached, as shown in FIG. 2, are typically integrated with the crankshaft 100A. Therefore, when the main sprocket S1 rotates, the pedals P also rotate at the same angular velocity. Therefore, as the bicycle speed increases, the angular velocity of the cranks C also increases proportionally. As a result, when the bicycle speed becomes excessive, for example, on a downhill slope, the cranks C also rotate at an excessively high angular velocity. This inevitably causes the feet and lower legs placed on the pedals P to oscillate up and down to follow the bicycle speed.

[0037] Therefore, for the crank C integral with the crankshaft 100A, for example, if a speed change gear mechanism is interposed at the connection with the crankshaft 100A so that, for example, one rotation of the crank causes the crankshaft 100A to rotate two times, the movement of the foot or lower limb pressing on the pedal P can be reduced, which is convenient. Furthermore, if the main sprocket S1 rotates at a speed exceeding a predetermined rotational speed, for example, when the rotational angular velocity of the main sprocket exceeds a certain value ω (rad / sec), the control unit can detect this and disconnect the crankshaft from the crank, and an electromagnetic clutch mechanism can be interposed between them so that, when the rotational angular velocity drops to the certain value ω, the two are mechanically reconnected.

[0038] Therefore, with a bicycle 100 configured in this way, even when the user of bicycle 100 is using it in a dangerous situation, such as going down a slope, the feet and lower legs placed on the pedals P do not have to be forced to move up and down to follow the pedals, allowing for safe riding. Furthermore, if the main sprocket S1 reaches an excessive rotational speed on a steep slope, the electromagnetic clutch mechanism can interrupt the rotation of the crankshaft 100A, eliminating the need to force the user to lift their feet off the pedals, as was previously the case, and further ensuring safety.

[0039] The motor 3 of this embodiment is fixed to the seat tube F2 by using a thin, approximately gourd-shaped or other unique fixing device 30 to clamp and hold both sides of the housing of the motor 3 from the left and right. Although the motor 3 is fixed to the seat tube F2, it may also be fixed to the top tube F3 or down tube F4, or between these tubes.

[0040] Furthermore, the motor 3 of this embodiment is a motor with a regenerative function, and when, for example, braking to slow down the bicycle, if a sudden speed drop information is output from the speed detector 4 to the control means 5, the control unit 51 that receives this sudden speed drop information outputs a control signal to the first electromagnetic switch SW1 to stop the power supply from the capacitor 2 to the motor 3, and the power supply to the motor 3 is immediately stopped. Furthermore, the motor 3 of this embodiment is brushless, and moreover, is a coreless type that does not generate resistance (cogging torque) caused by the action of an iron core and a permanent magnet, so it rotates smoothly. Na Rotational movement can also be achieved.

[0041] In this case, since this is an emergency and rapid control, the control unit 51 does not output a control signal to the electromagnetic clutch 8 to turn it off, but there is no problem because the motor 3, to which power supply is stopped, will be forced to rotate and there is no risk of adding an assist force to the crankshaft 100A. On the contrary, in this embodiment, the control unit 51, which receives information about such a sudden decrease in speed from the speed detector 4, determines that an emergency situation exists, and outputs a control signal to connect the circuit to the second electromagnetic switch SW2 while power supply to the motor 3 is still stopped, and the motor 3 and the rectifier 11 are urgently connected. As a result, the following four conditions are simultaneously satisfied: and That is, (i) Since the electromagnetic clutch 8 remains in an actuated connected state, the transmission of rotational force between the motor 3 and the assist gear 3C remains possible. (ii) The first electromagnetic switch SW1 is in an open state, so that power supply from the storage battery 2 to the motor 3 is stopped. (iii) The second electromagnetic switch SW2 is in a closed state, and the motor 3 and the rectifier 11 are connected to each other; (iv) the third electromagnetic switch SW3 is maintained in a closed state; When these four conditions are met, the motor 3, to which power supply is stopped, receives a rotational force from the assist gear 3C, forcing the rotor in the motor 3 to rotate, and with this rotation, an electromagnetically induced electromotive force is generated in the winding coil on the stator side, and this electromotive force is supplied to the battery 2 via the rectifier 11. As a result, it becomes possible to store the regenerated power in the motor 3 in the battery 2 (storage of power using regenerative energy).

[0042] That is, in this embodiment, by appropriately electrically connecting each part, when the motor 3 loses power from the capacitor 2, the rotational force from the crankshaft 100A, which is rotating due to the inertial force caused by the descent of the bicycle 100, is transmitted via the assist gear 3C back to the rotor (not shown) of the motor 3, driving the rotor to rotate, and as a result, an induced electromotive force is generated in the coil provided on the stator side (not shown). As a result, the regenerated electromotive force from the auxiliary motor 3 is output to the rectifier 11 along with the electromotive force from the main generator 1, so that the capacitor 2 is charged from two systems.

[0043] Furthermore, this regenerative motor 3 not only recovers regenerative power to the battery 2, but also functions as a brake for the bicycle 100 traveling at an excessive speed, such as exceeding the speed limit. That is, the motor 3 uses the rotational force (energy) of the crankshaft 100A to drive the rotor of the motor 3, and the load from the rotor on the crankshaft 100A generates a braking force. This allows the motor 3 to perform two functions: power generation and braking. Note that in this case, no pedaling force is generated by the pedals P of the rider of the bicycle 100, and the bicycle 100 is simply traveling by inertia.

[0044] Furthermore, like the generator described above, the motor used in the present invention is hardly subjected to resistance known as cogging torque, as described in Patent No. 4782303, and efficiently generates stable rotational driving force, so that it can exert sufficient assist force even when used as a power source when starting to ride a bicycle at low speeds.

[0045] When the control unit 51 detects that the battery 2 is fully charged, the third electromagnetic switch SW3 is opened by a control signal output from the control unit 51, preventing excessive power from being supplied to the battery 2. Furthermore, when a lithium-ion battery or the like is used as the battery 2, for example, the power density of the lithium-ion battery is high, and overcharging may result in ignition or smoke, which may lead to a fire. Therefore, if a safety device is incorporated that stops charging when the battery is fully charged, there is no need to provide the above-described configuration, i.e., the third electromagnetic switch SW3.

[0046] The speed detection means 4 detects the traveling speed of the bicycle. In this embodiment, as shown in FIG. 6, it is composed of a magnetic sensor 41 mounted on the front fork FF portion, which branches into left and right sides at the bottom of the front tube F1, and magnets 42 mounted at equal intervals on a hub plate 110A, which is mounted on a hub axle 100B of the front wheel W1 (hereinafter referred to as the "front hub axle 100B") and circumferentially surrounds the spokes 110B, in close proximity to the magnetic sensor 41. In this embodiment, the magnetic sensor 41 counts the number of times the magnet 42 mounted near the outer edge of the hub plate 110A of the front wheel W1 passes per unit time to detect the bicycle speed (hereinafter referred to as the "bicycle speed"). However, this configuration is not particularly limited. Furthermore, the detection medium is not particularly limited to a magnetic field, and may be, for example, an ultrasonic wave or the number of times light of a specific wavelength is received.

[0047] 7, the control means 5 includes a processing unit (hereinafter referred to as "control unit 51") with a CPU, a memory including RAM, ROM, etc. (not shown), and an interface (not shown) for connecting to various external circuits. In addition to being electrically connected to the battery 2, the control unit 51 in this embodiment has inputs connected to a speed detector 4, a torque detector 7, and setting buttons C, D, and S of an operation panel 9 (described later), and outputs connected to a first electromagnetic switch SW1 provided in the connecting wiring between the battery 2 and the motor 3, a second electromagnetic switch SW2 provided in the connecting wiring between the motor 3 and the rectifier 11, an electromagnetic clutch 8 that mechanically connects and disconnects the motor 3 and the assist gear 3C, the operation panel 5, and a third electromagnetic switch SW3 that stops the supply of power from the rectifier 11 when the control unit 51 detects that the battery 2 is fully charged.

[0048] The control unit 51 configured in this way controls the amount of power supplied from the lithium ion battery that constitutes the power storage device 2 to the motor 3 in accordance with the traveling speed of the bicycle 100 detected by the speed detection means 4, and in particular, when the detected bicycle speed exceeds a predetermined set value, it operates and controls the electromagnetic clutch 8 to prevent the application of rotational driving force from the motor 3. Furthermore, the control means 5 successively detects and monitors the charge level of the lithium ion battery that constitutes the power storage device 2, and when it is fully charged, it stops the supply of power to the lithium ion battery that constitutes the power storage device 2, thereby stopping the power supply from the charging means 2 to the motor 3. Electricity The control circuit is configured to control the on / off operation of a first electromagnetic switch S / W1 provided between connection wires for electrically conducting electricity.

[0049] Furthermore, in this embodiment, since the motor 3 is configured with a regenerative function, the control means 5 is also configured to control the on / off operation of the second electromagnetic switch S / W2 provided in the connection wiring from the motor 3 to the rectifier 11, as described above, in order to ensure electrical connection from the motor 3 to the lithium ion battery which is the storage battery 2.

[0050] The storage box 6 houses the capacitor 2 and the control means 5, and is installed in a roughly triangular or trapezoidal gap between the top tube F3 and the down tube F4. This installation space is made extremely thin in the left-right direction so as not to interfere with the movement of the legs of the user of the bicycle 100. The storage box 6 houses a circuit board (not shown), and on one side of this circuit board, a control unit 51 that constitutes the control means 5, as well as memory, an interface, and the like (all not shown), are mounted. Furthermore, multiple lithium-ion batteries that constitute the capacitor 2 are installed on the back side of this circuit board.

[0051] The torque detector 7 detects the torque acting on the crankshaft 100A, which is the main shaft of the main sprocket S1, due to the force of the foot pressing down on the pedal P. The torque detector 7 of this embodiment can detect situations such as when the bicycle 100 is going uphill, in which the force of the foot pressing down on the pedal P or the pedaling force of the bicycle 100 increases, causing an excessive load to act on the feet of the user of the bicycle 100. The torque detector 7 of this embodiment is composed of a known torque sensor provided near the crankshaft 100A, for example, and has an output connected to the input of the control unit 5. The torque detector 7 is configured to control the capacitor 2 to increase or decrease the amount of power supplied from the capacitor 2 to the motor 3 when the torque value exceeds or falls below a predetermined level.

[0052] The electromagnetic clutch 8 connects and disconnects the rotational force from the motor 3 between the output shaft 3A of the motor 3 and the rotating shaft of the main sprocket S1 (i.e., the crankshaft 100A). That is, when the rotation speed of the crankshaft 100A, which is the rotating shaft of the main sprocket S1, exceeds a certain value, the electromagnetic clutch 8 is activated under the control of the control means 5, and the transmission of the rotational force from the motor 3 to the crankshaft 100A, which is the rotating shaft of the main sprocket S1, is interrupted.

[0053] The operation panel 9 is provided with a selection switch located above the handlebar H of the bicycle body, which switches between supplying and halting power from the generator 1 to the battery 2, and supplying and halting power from the battery 2 to the motor 3, depending on the usage status of the bicycle 100. The operation panel 9 of this embodiment is equipped with a charge operation switch C for switching on the charge mode, a discharge operation switch D for switching on the discharge mode, i.e., when supplying power from the battery 2 to the motor 3, and a stop switch S for ending use of the bicycle. Note that when these switches C, D, and S are pressed once, they are turned on, and for example, the switch itself lights up blue. When pressed again, they are turned off, and for example, the switch itself changes from lit to unlit. By repeating this operation, the on and off states can be switched on and off. By combining the on and off operations of these switches, four modes optimal for various usage situations, as shown in FIG. 10, namely: 1) First mode: This is the initial mode state, which is the state when the user of bicycle 100 is about to start using it, has just finished riding it, or has temporarily stopped bicycle 100, such as when waiting at a traffic light. Note that in this first mode, for example, when no operation is performed on either charge operation switch C or charge operation switch D, or when stop switch S is operated, charge operation switch C and discharge operation switch D are reset and each are set to return to the OFF state. 2) Second mode: When the bicycle 100 starts to ride, the bicycle 100 itself is still traveling slowly and has not yet accelerated, so the pedaling force applied by the user to the pedals P is large. This means that the bicycle is in a state where assistance is most needed during bicycle riding (excluding steep uphill climbs), so charging is temporarily suspended (although it can be continued), and only power is supplied from the storage battery 2 to the motor 3. In this embodiment, the generator-side sprocket S, which is coaxial with the rotating shaft 1A of the generator 1 and meshes with the chain CH, may be configured, for example, to have an electromagnetic clutch (not shown) interposed between the rotating shaft 1A and the sprocket S, and the control output 5 may be configured to engage and disengage this electromagnetic clutch. In this configuration, in the second mode, which is a setting suitable for the start of riding, the electromagnetic clutch disconnects the rotating shaft 1A from the sprocket S, thereby conveniently reducing the pedaling force applied to the pedals P somewhat. 3)Third mode: In this mode, except when the bicycle road being ridden is sloped, the bicycle 100 itself will begin to accelerate after a certain amount of time has passed since the start of riding, so the user does not need to increase the force with which they apply pressure to the pedals P. Therefore, power is supplied from the battery 2 to the motor 3 at the same time that the power storage mode for the battery 2 is turned on. Therefore, the user riding the bicycle 100 can set this third mode by turning on the charge operation switch C and the discharge operation switch D on the operation panel 9. When switching from the second mode, the discharge switch D is already on, so there is no need to operate the discharge switch D. 4) 4th mode: This mode is used, for example, when the pedaling force of the user's feet on the pedals P on a flat road becomes excessive and the speed limit is exceeded, and power supply from the storage battery 2 to the motor 3 is stopped. Furthermore, by setting this fourth mode, especially when the bicycle 100 is traveling down a slope and is likely to go too fast, the motor 3, which is in a power supply stopped state, is dissipated in the opposite way to before, by transmitting the large rotational force from the crankshaft 100A of the bicycle 100 descending due to inertia to the motor gear 3B of the motor 3, which is then consumed as rotation of the rotor directly connected to the rotation of the motor gear 3B. This generates a load on the crankshaft 100A, which then brakes. This setting is used to prevent the bicycle from traveling at an excessively fast speed.

[0054] Therefore, the rider of the bicycle 100 can use the operation panel 9 to freely select and set any one of the four modes.

[0055] (Actions and effects of electric assist bicycles) Therefore, the electrically power assisted bicycle 100 of this embodiment is equipped with a generator 1 fixed to the seat tube F2 on the central side of the bicycle 100, a lithium ion battery constituting the capacitor 2 that stores the power generated by the generator 1, a regenerative motor 3 fixed to the seat tube F2 that is driven by power from the generator 1 and applies a rotational force to the crankshaft 100A in accordance with the traveling speed of the bicycle, a speed detection means 4 that detects the traveling speed of the bicycle 100, a control means 5 that controls the amount of power supplied from the capacitor 2 to the motor 3 in accordance with the traveling speed of the bicycle detected by the speed detection means 4, and a storage box 6 installed on the central side of the bicycle 100 to store the capacitor 2 and the control means 5. In this way, the electrically power assisted bicycle 100 of this embodiment has heavy parts such as the generator 1, the capacitor 2, and the motor 3 located in the central part of the body of the bicycle 100, making it possible to maintain an even weight balance between the front and rear wheels. Similarly, the electrically assisted bicycle 100 of this embodiment is not configured so that parts that are prone to breakdowns or require frequent maintenance, such as the generator 1, the storage battery 2, and the motor 3, are mounted on the rotating hub axles of the front and rear wheels, making them easy to attach and detach when repairing, inspecting, or replacing.

[0056] (Various control methods using control means for electrically assisted bicycles) Next, a method for controlling the motor 3 and a method for controlling the generator 1 by the control means 5 provided in the power-assisted bicycle 100 according to this embodiment will be described in detail with reference to the flowcharts of FIGS. 8 and 9, respectively.

[0057] (1) Motor control method: FIG. 8 is a flowchart showing a method for controlling the motor 3 by the control unit 5 of the power-assisted bicycle 100 according to one embodiment of the present invention, and is made up of a first step SA1 to a ninth step SA9.

[0058] In the first step SA1, when the user of the bicycle 100 begins to use the bicycle, for example, with their feet on the pedals P to pedal, they set the switches on the operation panel 9 to the second mode shown in FIG. 10, which starts the electric assist. That is, the operation here is to set the third mode by turning the charge operation switch C OFF and the discharge operation switch D ON. Therefore, when the user depresses the pedals P with their feet on them, the bicycle 100 starts moving with only a light pedaling force.

[0059] In the second step SA2, while the bicycle 100 is traveling, the control unit 51 of the control means 5 calculates whether the bicycle speed has reached a specified upper limit speed based on the speed signal input to the control means 5 from the speed detector 4, and determines at predetermined time intervals whether the upper limit speed, which is the speed limit stored in memory, has been reached. If the speed limit has been reached in this second step SA2, the process proceeds to the third step SA3.

[0060] In the third step SA3, the control means 5 outputs a control signal to the first electromagnetic switch SW1, and the first electromagnetic switch SW1 that receives this control signal performs an OFF operation. This breaks the electrical continuity between the capacitor 2 and the motor 3, and the power supply from the capacitor 2 to the motor 3 stops.

[0061] In the fourth step SA4, the assist force from the motor 3 is eliminated, and the bicycle 100 travels solely by the force of the foot pressing on the pedal P, so unless the pedaling force is intentionally increased, the traveling speed of the bicycle 100 decreases and does not exceed the upper speed limit. After this, the process returns to the second step SA2, and the same operations are repeated.

[0062] In fifth step SA5, if the control means 5 determines in second step SA2 that the speed limit has not been reached, the first electromagnetic switch SW1 continues to operate in an ON state, and therefore a control signal for turning this switch OFF is not output. As a result, the electrical continuity between the capacitor 2 and the motor 3 is maintained, and power supply from the capacitor 2 to the motor 3 continues.

[0063] In the sixth step SA6, it is determined whether the user of the bicycle 100 has finished using the bicycle and will stop the bicycle 100 from traveling. If the user intends to continue using the bicycle, the user continues to ride the bicycle without operating any switches on the operation panel 9, and the process returns to the original second step SA2, where the same operations are repeated. That is, the control means 5 continues to determine whether the upper limit speed has been exceeded at regular time intervals based on the speed information output from the speed detector 4 to the control means 5. On the other hand, if the user of the bicycle 100 has decided to finish using the bicycle, the process then proceeds to the seventh step SA7.

[0064] In seventh step SA7, the user stops using the bicycle 100, in other words, turns on the stop switch S on the operation panel 9.

[0065] In eighth step SA8, the operator turns on stop switch S, which outputs a stop signal from operation panel 9 to control unit 51 of control output 5. Control unit 51 receives this stop signal and outputs a control signal to first electromagnetic switch SW1, opening the connection where switch SW1 is located. This stops motor 3 from applying assist force to crankshaft 100A of bicycle 100.

[0066] In the ninth step SA9, the bicycle 100 slows down while moving due to the loss of the assist force from the motor 3, and since the bicycle 100 is moving only with the pedaling force of the operator's feet, the bicycle 100 can be stopped at the desired location by applying the brakes.

[0067] (2) Generator control: FIG. 9 is a flowchart showing a method for controlling the generator 1 by the control unit 5 of the power-assisted bicycle 100 according to one embodiment of the present invention, and is made up of a first step SB1 to a seventh step SB7.

[0068] In the first step SB1, when the user of the bicycle 100 begins to use the bicycle, for example, with their feet on the pedals P to pedal, they set the switches on the operation panel 9 to the second mode shown in FIG. 10, thereby starting the electrically assisted operation. That is, the second mode is set by turning the charging operation switch C OFF and the discharging operation switch D ON. Therefore, when the user depresses the pedals P with their feet on them, the bicycle 100 starts moving with only a light pedaling force.

[0069] In the second step SB2, the control unit 51 determines whether the charge mode is currently ON or not by operating the C switch on the operation panel 9, that is, whether the mode is one of the second to fourth modes in FIG. 10, and further whether the mode is the charge mode or not. i) For example, in the third mode, which is when riding a bicycle on a normal stable flat road, if it is determined that the mode is the charging mode, the process proceeds to the third step SB3. ii) On the other hand, if the traveling speed of the bicycle 100 is still slow and the user has just started using the bicycle in the second mode, that is, if it is determined that the speed is not stable and the bicycle is not in the charging mode, return to the first step SB1. iii) Furthermore, in the fourth mode, such as when the bicycle speed increases suddenly on a slope, power supply to the motor 3, i.e., any further increase in the bicycle speed, must be avoided (although it is preferable to perform braking operations with the motor 3 at the same time), but if the control unit 51 determines that charging the capacitor 2 will have little direct effect on braking operations with the motor 3, the control unit 51 proceeds to the third step SB3.

[0070] In the third step SB3, the current bicycle speed is detected from the speed information output from the speed detector 4 to the control unit 51, and the control unit 51 determines whether this detected bicycle speed exceeds the speed limit. If it is determined that the bicycle speed is a normal, safe speed below the speed limit, the process proceeds to the fifth step SB5. On the other hand, if it is determined that the speed limit is exceeded, the process proceeds to the fourth step SB4.

[0071] In the fourth step SB4, a control signal is output to turn off the first electromagnetic switch SW1 in order to stop the power supply from the storage battery 2 to the motor 3. Furthermore, in the state where the power supply to the motor 3 is stopped, a control signal is output to the second electromagnetic switch SW2 so as to turn on the second electromagnetic switch SW2. Furthermore, the control unit 51 does not need to perform any control on the third electromagnetic switch SW3 and the electromagnetic clutch 8, so they remain in the ON state. As a result, while the power supply to the motor 3 remains stopped, the rotational force from the crankshaft 100A to which the pedal P is attached is transmitted to the rotor on the motor 3 side, and electromagnetic induction is generated in the winding of the stator that faces the rotor. Origin Since electric power is generated, it can be stored as regenerative power in the storage battery 2. At the same time, the rotational force of the main sprocket S1 is transmitted via the assist gear 3C, forcibly rotating the rotor on the motor 3 side, and braking is applied to the main sprocket S1 in proportion to the rotational load, which functions similarly to the engine brake of a gasoline engine, thereby improving safety.

[0072] In the fifth step SB5, the electromotive force generated by the generator 1 is rectified by the rectifier 11, and further, the control unit 51 controls the third electromagnetic switch SW3 to be in an ON state, thereby connecting the rectifier 11 and the battery 2, and therefore the rectified electromotive force is supplied to the battery 2. Further, the control unit 51 controls the first electromagnetic switch SW1 to be in an ON state, thereby connecting the battery 2 and the motor 3, and therefore power is supplied from the battery 2 to the motor 3.

[0073] In the sixth step SB6, after determining that the speed is normal and below the speed limit, the process proceeds to the fifth step SB5. Thereafter, the control unit 51 determines whether or not the bicycle 100 should stop riding at regular time intervals (i.e., whether or not the bicycle should continue riding). If the bicycle is to continue riding, the process proceeds to the third step SB3, and the same operation is repeated again. On the other hand, if the bicycle rider wishes to stop riding at this point, the process proceeds to the seventh step SB7.

[0074] In seventh step SB7, switch S on operation panel 9 is pressed at approximately the same time as stopping the bicycle and getting off. This operation of stopping the bicycle 100 causes generator 1 to stop generating electricity and also stops the power supply from capacitor 2 to motor 3, so motor 3 also stops operating.

[0075] Therefore, in the electrically assisted bicycle 100 of this embodiment, the generator 1, which is relatively heavy, is fixed to the frame F of the bicycle 100, particularly to the seat tube F2, which is located toward the center of the bicycle 100. The motor 3, which is also relatively heavy, is fixed to the down tube F4, which is located toward the center of the bicycle 100, in the frame F.

[0076] Furthermore, the capacitor 2, which is normally expected to be the heaviest component, is constructed from a lithium-ion battery in this embodiment, so is not particularly heavy, but this lithium-ion battery is also housed in a thin, triangular storage box 6 attached to the gap between the top tube F3 and down tube F4, which are located midway in the frame F. Therefore, the center of gravity of the entire bicycle 100 is located toward the center of the bicycle 100, resulting in good weight balance and stable cycling.

[0077] Furthermore, according to this embodiment, the generator 1, the storage battery 2, and the motor 3 are all attached to any part of the frame F, so that there is no need to perform troublesome work such as removing the tire during regular inspections, repairs, or replacements, and the work can be carried out relatively easily and conveniently. Furthermore, according to this embodiment, the generator 1, the storage battery 2, and the motor 3 are all attached to any part of the frame F, so that in the case of an ordinary bicycle, the bicycle can be easily electrified simply by attaching these to a part of the frame and running appropriate wiring.

[0078] The technical scope of the present invention is not limited to the above-described embodiment, but extends to the matters set forth in the claims and their equivalents.

[0079] In other words, the present invention is not limited to the above-described embodiments, but also includes configurations in which the components disclosed in the above-described embodiments are mutually replaced or the combination is changed, publicly known inventions, and configurations in which the components disclosed in the above-described embodiments are mutually replaced or the combination is changed.

[0080] For example, the motor according to the present invention is not limited to a motor with a regenerative function as in this embodiment, and various types of motors are applicable. Furthermore, the electrically power-assisted bicycle of the present invention includes not only two-wheeled vehicles, but also various types of vehicles, such as those for towing luggage vehicles such as tricycles and auto rickshaws, and those for towing a passenger body at the rear of a tuk-tuk or the like.

[0081] As described above, the present invention may also be configured such that a speed change gear mechanism is interposed between the crank and crankshaft to reduce the rotational speed of the crank compared to the rotation of the crankshaft. Furthermore, an electromagnetic clutch mechanism may be interposed between the crankshaft and crank to disconnect them when the main sprocket rotates at a speed exceeding a predetermined rotational speed, and mechanically reconnect them when the rotational angular velocity has decreased to a certain value. [Explanation of symbols]

[0082] 1. Generator 1B Mounting plate 1C Bracket 1D fixed shaft 1E Large shaft with flange 1R rotor 1S stator 2. Storage means (capacitor) 3. Motor with regenerative function 3A output shaft 3B motor gear 3C Assist Gear 30 Fixtures 4 Speed ​​detection means 41 Magnetic Sensor 42 Magnet 5. Control measures 51 Control section 6 Storage Box 7 Torque detector 8 Electromagnetic Clutch 9 Operation Panel 100 Electric Assist Bicycles 100A Crankshaft (sprocket rotating shaft, crank main shaft) 100B hub axle (front hub axle) 100C hub axle (rear hub axle) 110A hub plate 110B spokes CH Chain F Frame F1 Front Tube F2 seat tube F3 Top Tube F4 down tube F5 rear top tube F6 rear down tube FF front fork H Handle L Lamp MG permanent magnet S sprocket (generator side) S1 main sprocket S2 rear sprocket (rear wheel side) SD Saddle SW1 First electromagnetic switch SW2 Second electromagnetic switch SW3 Third electromagnetic switch W1 front wheel W2 rear wheel

Claims

1. a speed detection means for detecting the traveling speed of the bicycle; a generator fixed to a seat tube constituting a frame between the front and rear wheels, and equipped with a power-generating sprocket that meshes with a chain stretched between a main sprocket mounted on a crankshaft having pedals and a rear sprocket mounted on a hub shaft of the rear wheel; a power storage means for taking in and storing the power generated by the generator; a motor fixed to a portion of the frame between the front and rear wheels, driven by power supplied from the generator or the power storage means, and applying a rotational force to the crankshaft corresponding to the traveling speed of the bicycle detected by the speed detection means; a control means for controlling the amount of power supplied from the power storage means to the motor in accordance with the traveling speed of the bicycle; a housing box that is installed in a gap between frames between the front and rear wheels and that houses at least the power storage means and the control means; Equipped with the motor and the generator are arranged so as to partially overlap the main sprocket in the axial direction of the main sprocket, the crankshaft of the main sprocket is provided on a line connecting the output shaft of the motor and the rotating shaft of the generator, and the output shaft and the rotating shaft are further provided on the seat tube. An electrically assisted bicycle.

2. a torque detector for detecting torque generated when a foot force on the pedal acts on the crankshaft of the main sprocket; The control means detects the change in torque and controls the power storage means in accordance with the amount of change in torque, thereby increasing or decreasing the amount of power supplied from the power storage means to the motor.

2. The electrically assisted bicycle according to claim 1, wherein the electric motor is a

3. an electromagnetic clutch for connecting and disconnecting rotational force from the motor between the output shaft of the motor and the crankshaft of the main sprocket; When the number of revolutions of the crankshaft of the main sprocket or the speed of the bicycle exceeds a certain value, the clutch is activated by control of the control means to interrupt the transmission of rotational force from the motor to the crankshaft of the main sprocket.

3. The electrically assisted bicycle according to claim 1 or 2.

4. The motor has a regenerative function, When the bicycle speed input from the speed detection means exceeds a certain value, the control means stops the power supply from the generator or the power storage means to the motor, and The regenerative power of the motor, which is generated when the rotational force of the main sprocket is transmitted to the motor, is output to the power storage means.

4. The electrically assisted bicycle according to claim 1, wherein the electric motor is a motor.

5. The generator and / or motor has a unique magnetic flux distribution formed by forming a magnetic circuit through a unique arrangement and configuration of permanent magnets provided inside.

5. The electrically assisted bicycle according to claim 1.

6. The arrangement and arrangement of the permanent magnets of the generator and / or motor are configured to have a Halbach array magnetic field.

6. The electrically assisted bicycle according to claim 5.

7. At least, the generator has a brushless and coreless structure.

7. The electrically assisted bicycle according to claim 1.

8. an operation panel provided on the front side of the bicycle body and having a switch for switching between supplying and suspending power from the generator to the power storage means and supplying and suspending power from the power storage means to the motor according to the state of use of the bicycle; 8. The electrically assisted bicycle according to claim 1, wherein the electric motor is a motor.

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