JP2001080570A - Vehicle with auxiliary motive power - Google Patents

Abstract

PROBLEM TO BE SOLVED: To always accurately secure the assist force when necessary, and to improve the traveling continuous time by setting a low assist ratio area for limiting the assist ratio till a value of a human power driving unit rises to the predetermined value in a control circuit for controlling an electric driving unit at a value corresponding to the torque detection value. SOLUTION: When a large human power is applied to a pedal when starting or accelerating a bicycle or traveling on a slope upward, a torque sensor 52 detects this torque and outputs it to a microcomputer 58. The microcomputer 58 connected to a constant voltage circuit 60 for lowering the voltage of a battery 22 controls the drive of a motor 39 through an inverter circuit 59 so as to generate the necessary electric assist force. In the condition that a mode changeover switch 74 selects the predetermined mode, a low assist ratio area is set till the human driving force rises to the predetermined value, and the assist traveling by the electric driving force is not performed. When the human driving force is lowered to other predetermined value, control is returned to the low assist area, and the electric driving force is canceled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a human-powered driving unit for driving wheels by a human-powered driving force, and an electric-powered driving unit that operates according to the magnitude of the human-powered driving force. The present invention relates to a vehicle with auxiliary power that can travel.

[0002]

2. Description of the Related Art Conventionally, this type of vehicle with auxiliary power, for example, an electrically assisted bicycle, includes a human-powered drive unit that drives wheels by manual power as described in Japanese Patent Application Laid-Open No. 10-67377 (B62M23 / 02). An electric drive unit that operates in accordance with the magnitude of the manual driving force, and the ratio of the electric driving force to the manual driving force, that is, the assist ratio is artificially switched to provide the assist ratio according to the user's preference. The vehicle can travel with these driving forces. The preset assist ratio to be switched is changed so that the assist mode is always constant according to the manual driving force and the assist ratio increases according to the manual driving force when the manual driving force is small. It has two modes, an economy mode.

[0003] Switching of the assist ratio in such a vehicle has been performed by switching a switch at hand.

However, in the case of a vehicle with auxiliary power as described above, the assist ratio changes according to the magnitude of the human-powered driving force when the human-powered driving force is small, for example, when the vehicle is traveling on a flat ground or downhill. However, in such a case, the vehicle can be sufficiently driven only by manual driving without assistance, and the battery is consumed when assistance is unnecessary by setting in this manner. As a result, there is a problem that the traveling distance per charge is shortened.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned drawbacks. When assisting is required, a sufficient assisting force, that is, so-called assisting force, can be obtained. It is an object of the present invention to provide a vehicle with an auxiliary power which can extend the power.

[0006]

SUMMARY OF THE INVENTION The present invention provides a human-powered driving unit for driving wheels by human power, a torque detecting unit for detecting the human-powered driving force of the human-powered driving unit, and an electric driving unit for driving the wheels by a motor. And a control circuit for inputting a detection value of the torque detection unit and outputting a control signal for driving the electric drive unit with a magnitude corresponding to the detection value, the control circuit comprising: A low assist ratio region for setting an assist ratio, which is an output ratio of the electric driving force to the manual driving force, to a predetermined value or less.

Further, the control circuit includes a predetermined value of the manual driving force when the manual driving force is increased and the low assist ratio region is released, and a manual power when the human driving force is reduced and the low assist ratio region is entered. It is characterized in that the driving force differs from a predetermined value.

Further, the control circuit is configured to reduce the assist ratio change rate when the human-powered driving force decreases and enters the low-assist-ratio region as compared with when the human-powered driving force is increased and the low-assist-ratio region is released. It is characterized by being made smaller.

[0009] The assist ratio in the low assist ratio region is 0 or a value near 0.

Further, when the low assist ratio region is released, the assist ratio is constant.

Further, the assist ratio after the cancellation of the low assist ratio region is one.

Further, the control circuit is characterized in that a plurality of assist ratios, which are ratios of the electric driving force to the manual driving force, are provided in advance, and one of them is provided with a low assist ratio region.

The predetermined value of the manual driving force when the manual driving force is increased and the low assist ratio region is released is set to 100 kg · cm or more. The predetermined value of the manual driving force at the time of entering is set to 50 kg · cm or less.

The operation of the above configuration will be described.

In such a vehicle with auxiliary power, the motor is driven in accordance with the magnitude of the manual driving force detected by the torque detecting unit, and the vehicle runs with the manual driving force and the electric driving force of the motor. Then, when the magnitude of the human-powered driving force is small, such as when traveling on a flat ground or traveling downhill, that is, when the magnitude is smaller than a predetermined value, the assist ratio for the human-powered driving force is set to a predetermined value or less, for example, 0 or a value close to 0, There is almost no assistance by electric driving force. This is called a low assist ratio region. Further, when the human-powered driving force becomes equal to or more than a predetermined value, for example, when traveling uphill or starting, the vehicle is driven by using both the human-powered driving force and the electric driving force so as to assist with a normal assist ratio, for example, 1. It has become.

The low assist ratio region is when the human-powered driving force increases and the vehicle exits from this region.
At the time when the human power becomes small and it enters this area,
The predetermined value is made different, for example, about 150 kg · cm when exiting, about 50 kg · cm when entering, and is smaller than the value when exiting when entering.

In addition, the rate of change of the assist ratio at this time is set to be smaller than the change rate at the time of exit, and the change rate at the time of entry is made smaller, so that when the human-powered driving force reaches a predetermined value, the speed can be quickly increased. When assisting, when exiting, the ratio is gradually reduced according to the size of human driving force, so when human driving force falls, suddenly there is no assistance and the pedaling weight will be heavy. Absent.

Further, a plurality of types of assist ratios are set, and a mode in which such a low assist ratio region is provided is set in one of the modes, and a switch for switching the mode or automatic switching is provided. You may.

With this configuration, sufficient assistance is provided only when the manual driving force is large, that is, when the assistance by the electric driving force is required, and the traveling becomes very easy.
When the assistance by the electric driving force is not required, the assistance is not provided, so that the battery consumption can be saved.

Further, since the predetermined value of the manual driving force is changed between when the vehicle enters the low assist ratio region and when the vehicle exits the low assist ratio region,
When the electric driving force goes up and down near the predetermined value of the human driving force, the electric driving force does not repeat on and off, and the riding comfort is greatly improved.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a vehicle with auxiliary power according to the present invention will be described by taking an electric assist bicycle as an example.

The vehicle with auxiliary power according to the present invention is not limited to an electrically assisted bicycle, and it is needless to say that all vehicles that are assisted by a motor, such as an assist-type electric wheelchair, are included.

Regarding the configuration of the whole electric assist bicycle,
This will be described with reference to FIG.

1 is a head pipe 2 provided at the front part,
The main frame is connected to a seat tube 4 provided below the saddle 3, and a pedal 5 which can be rotated by human power is attached to a portion where the main frame 1 and the seat tube 4 are connected.

Reference numeral 6 denotes a front wheel which is linked with the movement of the steering wheel 7 and determines the traveling direction by operating the steering wheel 7. The front wheel 6 comprises a spoke 8, a rim 9, and a tire 10.

Reference numeral 11 denotes a rear wheel serving as a driving wheel.
The vehicle also includes a tire 12, a rim 13, spokes 14, and a drive unit 15 for driving the rear wheel 11. The drive unit 15 has a built-in torque sensor 52, which will be described later, that detects a human-powered driving force transmitted via the chain 16.
In addition, a microcomputer 58 that inputs the value of the torque sensor 52 and outputs a drive signal to a motor 39 described later is built in.

Reference numeral 17 denotes a front sprocket which rotates with the rotation of the pedal 5. The front sprocket 17 includes a chain.
16 is engaged and the rotation of the front sprocket 17 is
After being provided on 15 axles 18, power is transmitted to sprockets 19. As described above, the rear wheel 11 is provided with an electric drive unit 20 including the drive unit 15 having a motor 39 therein.
And a human-powered drive unit 21 including the pedal 5 and the chain 16 and the like, and can travel.

Reference numeral 22 denotes a battery serving as a power source for a motor 39 described later, which contains a 24-volt NiCd battery. The battery 22 is removable and can be charged indoors when charging. The battery 22 includes the seat tube 4
And a lock device 23 is provided so as to be locked below the saddle 3.

Reference numeral 24 denotes a front basket, and reference numeral 25 denotes a stand for supporting a bicycle during parking.

An illumination device 26 illuminates the front brightly during night driving. The lighting device 26 includes a power generation dynamo and a lamp.

Reference numeral 27 denotes a brake lever for braking the rear wheel 11.

A travel mode changeover switch (not shown) for changing the assist ratio is provided near the grip of the steering wheel 7.

Next, the drive unit 15 of the electric assist bicycle
Will be described with reference to FIGS. 1 and 2.

An internal transmission 28 is provided at a part of the axle 18 in the longitudinal direction. The transmission 28 is connected to the rear sprocket 19 via a one-way clutch (not shown). Therefore, power is transmitted only in one direction of the pedal 5, and when the pedal 5 is rotated in the reverse direction, power transmission from the transmission 28 is cut off.

Reference numeral 29 denotes a rotary casing which forms a hub of the rear wheel 11 with the axle 18 as a center.
One is a rotating casing 29A provided with a U-shaped ring 30 for attaching the spokes 14 on the outer periphery, and the other is mounted on the axle 18 via a bearing 31, and The rotating casing 29B is fixed to the ring 30 by screws at a plurality of locations so as to close the opening of the casing 29A.

The rotary casing 29B is fixed to the rotary casing 29B by welding and is concentric with the axle 18.
A rotating piece having a disk-shaped upright wall formed outward, and the inner periphery of the rotating piece 32 is slid outwardly by the operation of the brake lever 27, that is, the rotating casing 29 A brake device 33 for braking the rotation is provided. Reference numeral 34 denotes a brake cover that covers the outside of the brake device 33.

Reference numeral 35 denotes a cord for supplying power from the battery 22 to a control board 40, which will be described later. The cord 35 penetrates the brake cover 34 and is inserted through a partially cutout portion of the axle 18 to be described later. The control board 40 is connected along the outer wall of the fixed casing 36 and partially along the inner wall of the fixed casing 36.

Reference numeral 36 denotes a bowl-shaped fixed casing provided in the rotary casing 29 and fixed to the axle 18 and having an open surface. The fixed casing 36 incorporates a DC brushless motor 39 and a planetary gear reduction mechanism described later. ing. The fixed casing 36 is fixed to the axle 18 where the transmission 28 in the longitudinal direction of the axle 18 is not provided.

Numeral 38 denotes a stator constituting a motor 39 provided on the inner surface of the fixed casing 36.
Is a control board provided on the outer surface of the fixed casing 36.
Powered via 40. Further, the stator 38 includes:
A winding is wound around an iron core forming 18 slots.
Has a two-pole magnet.

Reference numeral 41 denotes a rotor rotatably provided on the inner periphery of the stator 38 via two bearings 42 provided on the inner side wall of the fixed casing 36.
It is attached to a gear portion 43 forming a small diameter portion forming a partial gear. The gear portion 43 is a portion corresponding to a sun gear of planetary gear reduction mechanisms 43, 44, and 45 described below. Also,
The rotor 41 has a magnet 41a.

The rotor 39 and the stator 38 together constitute a motor 39. In this embodiment, the DC brushless motor is used. However, another type of motor may be used, and by using a stepping motor or the like,
It goes without saying that the configuration can be made more compact.

Reference numeral 44 denotes the gear portion 43 and the fixed casing.
The planet gear 44 meshes with a fixed gear 45 fixed to the inner periphery of the fixed casing 36 and the gear portion 43, and rotates around the axle 18 by rotation of the rotor 41. To rotate. Reference numeral 46 denotes an output panel which is rotatably provided at the center of each of the planet gears 44 and is rotatably provided via a bearing 47 provided on the axle 18.
The rotating casing 29B is provided with a one-way clutch 48 having a ratchet mechanism. The one-way clutch 48 cuts off the manual driving force and the power of the motor 39 when the rotation speed of the rear wheel 11 becomes faster than the rotation of the rotary casing 29 by human power.

Reference numeral 49 denotes a pressing piece fixed to the outer periphery of the transmission 28. The pressing piece 49 is fixed to the transmission 28 and closes an opening formed between the transmission 28 and the rotary casing 29. Disc-shaped collar provided to close the opening formed in size
50 and pressing plates formed at two positions opposite to each other with the collar 50
An elastic spring 61 is provided between the push plate 51, that is, the input portion of the rotating body, and the rotating casing 29, that is, the output portion of the rotating body. And
When the manual driving force is transmitted from the transmission 28, the spring 61 is contracted by a contraction amount corresponding to the magnitude of the manual driving force to rotate the rotary casing.
Rotate 29.

Reference numeral 62 denotes an elongated hole 71 formed on the push plate 51 side, one end 72 is movably attached, and the other end 73 is connected to the rotary casing 29.
It is a variable member rotatably mounted, that is, an arc-shaped ring. A total of two rings 62 are provided so that one end 72 comes near the portion where the spring 61 is provided. The ring 62 is made of a conductive material or a magnetic material. In this embodiment, an aluminum ring 62 is used.

Reference numeral 53 denotes a detection member, that is, a coil provided on the inner periphery of the ring 62 which is displaced by the contraction of the spring 61.
The coil 53 is supplied with power from the control board 40 having a control circuit, and inputs an electric signal to the control board 40 as a change in inductance due to the displacement of the ring 62 as a magnitude of human driving force.
The motor 39 is controlled based on this signal value. The above-described spring 61, ring 62, coil 53, and the like are collectively referred to as a torque detecting unit, that is, a torque sensor 52.

Reference numeral 68 denotes a position detection sensor for detecting the rotational position of the rotor 41 necessary for controlling the drive of the motor 39. A signal from the position detection sensor 68 is input to the microcomputer 58 to generate a motor control signal. I have.

The operation of the ring 62 will be specifically described with reference to FIG.

When a large amount of human force is applied, the spring 61 is greatly contracted, whereby a force is exerted on one end 72 of the ring 62 on the side of the push plate 51 in the circumferential direction. 62 moves inward. At this time, one end 72 of the ring 62 near the pressing plate 51 moves inward because the spring 61 moves by contraction of the spring 61, but the other end 73 does not displace because the other end 73 is pivotally attached to the rotating casing 29. After all, the ring 62 is displaced inward about the other end 73 as an axis. That is, the ring
62 is displaced from the position of the solid line to the state of the two-dot chain line. When the applied large human power is lost, the push plate 51 is returned to the original position by the restoring force of the spring 61, and one end 72 of the ring 62 near the push plate 51 is moved to the other end of the ring 62 by the operation.
It is put back around 73. That is, when the human power is lost, the ring 62 is displaced in a direction to spread outward as shown by a solid line.

As described above, since the ring 62 whose displacement varies depending on the contraction of the spring 61, that is, the magnitude of the human driving force, the inductance of the coil 53 can be changed according to the magnitude of the human driving force. The magnitude of the driving force can be output as an electric signal.

Next, the operation will be described with reference to the power system diagram of FIG.

First, the transmission of the power of the manual driving force will be described.

When a manual driving force is input from the pedal 5,
The front sprocket 17 fixed to the pedal 5 rotates, and the rear sprocket 19 rotates via the chain 16. When the rear sprocket 19 rotates, power is transmitted only in one direction by a one-way clutch (not shown).

When the power in the traveling direction is transmitted, the transmission is shifted by the transmission 28 set to the gear ratio specified by the user,
The rear casing 11 can be rotated by rotating the rotary casing 29 while contracting the spring 61 constituting the torque sensor 52.

Next, transmission of the power of the electric driving force will be described.

The change in inductance detected by the coil 53 due to the displacement of the ring 62 of the torque sensor 52 is input to the microcomputer 58 of the control board 40. Then, based on the signal value, a signal is output to the inverter circuit 59, the polarity of the stator 38 is changed by turning on and off the FET in the inverter circuit 59, and the magnet provided on the rotor 41 rotates the rotor 41, and the motor 39 Drive. The driving of the motor 39 is reduced by a planetary gear reduction mechanism, that is, a gear portion 43, a planet gear 44, and a fixed gear 45, and an output is taken out by an output panel 46 connected to the planet gear 44,
The rotary casing 29 is rotated via the ratchet 48.
Then, the rear wheel 11 comes to rotate.

As described above, the manual driving force and the electric driving force are combined by the rotary casing 29 to drive the rear wheel 11.

Next, a control circuit of the electric assist bicycle according to the present embodiment will be described with reference to FIG.

First, the operation of the torque sensor 52 will be described.

When a large force is applied to the pedal 5 at the time of starting the bicycle, accelerating the vehicle, climbing a hill, or the like, the power is transmitted by sandwiching the spring 61 between the flange portion 50 and the rotary casing 29. Shrinkage corresponding to the size occurs. At this time,
The displacement of the ring 62 changes the inductance of the coil 55.

The change in the inductance is input to the microcomputer 58 as an electric signal. Then, a drive signal for driving the motor 39 is output based on this signal.

Next, parts of the control circuit other than the torque sensor 52 will be described.

Reference numeral 58 denotes a microcomputer which receives a signal from the torque sensor 52 and outputs a drive signal to an inverter circuit 59 in accordance with the magnitude of the signal of the manual drive force.
Is connected to a constant voltage circuit 60 for stepping down the voltage of the battery 22, and operates using this as a power supply. And microcomputer 58
The driving signal output from the switching circuit switches a plurality of FETs in the inverter circuit 59 to output U, V, W signals to the stator 38 of the motor 39 to rotate the rotor 41. A signal line for detecting the position of the rotor 41 is connected to an input port of the microcomputer 58 to detect the position of the rotor 41.

Reference numeral 74 denotes a mode changeover switch provided near the grip of the steering wheel 7 for selecting a plurality of preset assist ratio patterns by switching and selecting a traveling mode by the user.

A first embodiment of the operation of the control circuit will be described with reference to FIGS.

The graph shown in FIG. 7 shows the ratio of the electric driving force to the human driving force, that is, the change in the so-called assist ratio with respect to the human driving force. As for this assist ratio, table data of two assist ratios according to the mode set by the user is stored in the microcomputer, and the assist ratio according to the magnitude of the manual driving force is set according to the mode. As shown in the graph. Explaining this graph, the graph shown by the broken line is the table data of the standard assist ratio. When the manual driving force is 0, the assist ratio is also 0, and the assist ratio draws a curve as the human driving force increases. It is gradually increasing. And the human power is 15
The assist ratio is set to 1 at 0 kg · cm. When the human driving force is 35 kg · cm or more, it overlaps with the solid line B.

Next, a case where another mode is entered will be described. In this mode, as shown by the solid line, when the manual driving force increases from 0, the solid line of A is followed, and the assist ratio is 0 up to the human driving force of 150 kg · cm,
If it exceeds 0 kg · cm, it will increase linearly to the assist ratio of 1. Also, once the assist ratio becomes 1, this time B
When the human-powered driving force is 150 kg · cm or more, the assist ratio is 1, but when the human driving force is 150 kg · cm or less, the curve follows the same curve as the standard mode described above. Then, the human power decreases and 35kg · c
When it reaches m, the assist ratio becomes zero.
A state where the assist ratio is 0 when the manual driving force is up to 150 kg · cm is defined as a low assist ratio region L.

As described above, the human driving force is 150 kg · cm.
It is set so as to have a hysteresis when it becomes above and when it becomes below.
This prevents the assist ratio from becoming 0 or 1 when going around cm.

Based on the graph of FIG. 7 described above, the setting of the assist ratio associated with the actual operation will be described with reference to the flowchart of FIG.

First, the microcomputer detects the mode of the assist ratio during traveling set by the mode changeover switch 74 (S1), and refers to the standard mode (broken line) table data in the graph shown in FIG. It refers to the table data of another mode (solid line) or determines which mode is being entered (S2). When the mode is the standard mode, the magnitude of the manual driving force detected by the torque sensor 52 at that time is read (S
3) The required electric driving force is calculated from the broken-line table data shown in FIG. 7 (S4). Then, a PWM output is generated and output so that the output electric driving force becomes the magnitude (S5).

In step S2, when the setting of the assist ratio during running is in a mode other than the standard mode, the human-powered driving force detected by the torque sensor 52 is detected (S6), and is temporarily input to the memory in the microcomputer. (S
7). And at this time, the human driving force was 150 kg in the past.
It is determined whether or not cm has been exceeded (S8). If it has not exceeded cm, the human-powered driving force is increasing from 0, so the solid line A in FIG. 7 is set as table data and the electric driving force is calculated. (S9). Then, a PWM output is generated and output so that the output electric driving force becomes the magnitude (S10).

If the manual driving force exceeds 150 kg · cm in the past in S8, it is determined that the manual driving force is going from the larger one to the smaller one, and the solid line B in FIG. It is set as data, and the electric driving force is calculated (S11). Then, an electric driving force corresponding to the human driving force that changes each time is output (S12), and it is determined whether the human driving force is lower than 35 kg · cm (S13). Clear (S14). Human power is 35kg ・ c
If not less than m, the memory is sequentially input, and the electric driving force is output according to the solid line B shown in FIG.

According to this flowchart, when the assist ratio mode switch 74 selects the standard mode, the assist ratio is obtained based on the broken line table data shown in FIG. The electric driving force is output at the corresponding assist ratio. Further, when the mode selection of the assist ratio selects another mode, or when the human-powered driving force increases from 0, such as immediately after the start of traveling, the assist ratio is obtained based on the table data of the solid line A shown in FIG. Thus, an electric driving force with respect to the manual driving force is output. In addition, once the human driving force is 150
When it becomes more than kgcm and goes down from there, for example,
When the vehicle starts traveling and travels on a level ground, or when the vehicle runs on a level ground after climbing an uphill, the assist ratio is calculated based on the table data of the solid line B, and the electric driving force is output. You.

That is, at the start of traveling, the human-powered driving force is 15
Until the pressure becomes 0 kg · cm or more, the low assist ratio region L
Therefore, there is no assistance by the electric driving force, and the assist traveling is not performed. In addition, human driving force is 150kgcm
At this point, the assist by the electric driving force is performed at the assist ratio 1, and when the human driving force becomes 35 kg · cm or less, the operation returns to the low assist ratio region L, and the vehicle runs only with the human driving force without the electric driving force. Become.

Next, the setting of the assist ratio with respect to the manual driving force described with reference to FIG. 7 of the first embodiment will be described with reference to FIG. 8 as a second embodiment.

In this embodiment, only the setting of the assist ratio with respect to the manual driving force is changed, and the overall configuration and the like are the same as in the first embodiment.

In the present embodiment, the assist ratio is set as shown by a broken line in the standard mode, and in other modes, the low assist ratio region L is set to 0 as the low assist ratio region L when the driving power is 150 kg · cm at the start of traveling. Is set. And
100k once human power exceeds 150kgcm
The electric driving force is output so that the assist ratio becomes 1 up to g · cm. When the electric driving force becomes 100 kg · cm or less, the vehicle enters the low assist region L, and the assist ratio becomes 0 and the vehicle travels only with the manual driving force. Also in the present embodiment, hysteresis is provided when exiting and entering the low assist ratio region L, and becomes 0 or 1 at the boundary where the assist ratio changes.
It is set so that the assist ratio does not change frequently.

Next, the setting of the assist ratio with respect to the manual driving force described with reference to FIG. 7 of the first embodiment will be described with reference to FIG. 9 as a third embodiment.

In this embodiment, only the setting of the assist ratio with respect to the manual driving force is changed, and the overall configuration and the like are the same as in the first embodiment.

In the present embodiment, the assist ratio is set such that the curves of the assist ratios from 0 to 1 and from 1 to 0 are obtained by adding curves to those shown in FIG. Size is 150kg ・ cm or 100kg
・ It is designed to prevent the assist ratio from changing suddenly when it reaches cm. In this graph, a curve shown by a broken line indicates the standard mode.

Next, the setting of the assist ratio with respect to the manual driving force described in FIG. 7 of the first embodiment will be described with reference to FIG. 10 as a fourth embodiment.

In this embodiment, the assist ratio in the low assist ratio region L in the setting of the assist ratio for the manual driving force shown in FIG. 7 is changed. In FIG. 7, the low assist ratio region is set to 0. On the other hand, in the present embodiment, the output is 0.05, which is a small ratio of the electric driving force to the human driving force.

Next, the setting of the assist ratio with respect to the manual driving force described in FIG. 7 of the first embodiment will be described with reference to FIG. 11 as a fifth embodiment.

In the present embodiment, only the setting of the assist ratio with respect to the manual driving force is changed, and the overall configuration and the like are the same as in the first embodiment.

In the present embodiment, the assist ratio is set so that the low assist ratio region is set smaller than the assist ratio region shown in FIG. 10 so that the assist ratio changes from 0 to 1 when the assist ratio becomes 100 kg · cm or more. Has become. Also,
When the human-powered driving force is reduced, the assist ratio is switched from 1 to 0 at 35 kg · cm. In the case of this embodiment, unlike the embodiment described above,
In the case of the above-described embodiment, the assist ratio changes from 0 to 1 at 150 kg · cm.
150 kg in which the assist ratio changes from 0 to 1 in cm and the assist ratio in the standard mode indicated by the broken line changes from 0 to 1
・ It is set smaller than cm.

As described above, the value of the manual driving force when the assist ratio is 1 is different between the standard mode and the other modes, and the value of the manual drive force when the assist ratio becomes 1 in the other mode is higher than when the assist ratio becomes 1 in the standard mode. And the value of the manual driving force when the electric driving force starts to operate is set to be slower in the other modes than in the standard mode. In the same manner as in the case of (1), the assist by the electric driving force is set to be started up quickly, so that the assist by the electric driving force is large and can be performed quickly.

In the above-described embodiment except the fourth embodiment shown in FIG. 10, the low assist ratio region L is set to 0. However, it is not necessary to set the low assist ratio region L to 0. Power assistance may be provided.

As described above, the assist ratio with respect to the manual driving force is set to 0, up to a predetermined manual driving force.
Alternatively, since the low assist ratio region L having a value close to 0 is provided,
When the human driving force is large and the electric driving force is required, the electric driving force can be surely assisted, and when the human driving force is small, the electric driving force does not operate, so that the battery can be prevented from being consumed.

The low assist ratio region L is determined when the human-powered driving force increases and exits from this region.
At the time when the human power becomes small and it enters this area,
Since the hysteresis is provided so as to make the predetermined value different, when the vehicle is running near the set value of the manual driving force, the assist ratio may be frequently changed to 0 or 1 when the vehicle is running near the set value. No, the riding comfort is improved.

The rate of change of the assist ratio at this time is set to be smaller than the change rate at the time of exit, and the change rate at the time of entry is smaller than that at the time of exit. When assisting, when exiting, the ratio is gradually reduced according to the size of human driving force, so when human driving force falls, suddenly there is no assistance and the pedaling weight will be heavy. Absent.

Since the assist ratio in the low assist ratio region is 0 or a value near 0, the battery consumption can be suppressed in the low assist ratio region.

When the low assist ratio region L is released, the assist ratio is constant, for example, set to 1, so that when the electric driving force becomes necessary, a sufficient assisting force can be obtained quickly. At the same time, it can respond to laws in Japan.

Further, a plurality of types of assist ratios are set, a mode in which such a low assist ratio region L is provided in one of the modes is set, and a mode switching switch or automatic switching is performed. Therefore, the user can appropriately set the traveling mode, and can perform traveling as desired, thereby improving usability.

The predetermined value of the low assist ratio region L differs between when the human-powered driving force increases and exits from this region, and when the human-powered driving force decreases and enters this region. For example, about 150 kgcm when exiting, about 35 kgcm when entering
And the value at the time of exit is smaller than the value at the time of exit, so that it can be effectively assisted by the manual driving force that needs the assistance by the electric driving force, and by providing the set value of the human torque with hysteresis. In addition, the assist ratio does not change frequently, and the riding comfort is improved.

[0094]

According to the first aspect of the present invention, the assist ratio with respect to the human driving force is set to a low assist ratio region in which the assist ratio is equal to or less than a predetermined value up to a predetermined human driving force. When the electric driving force is required, the electric driving force can be surely assisted, and when the electric driving force is small, the electric driving force does not operate, so that the battery can be prevented from being consumed.

Further, the invention according to claim 2 is characterized in that the low assist ratio region is determined when the human-powered driving force increases and exits from this region, and when the human-powered driving force decreases and enters this region. Since the hysteresis is provided so as to make the predetermined value different, the assist ratio frequently changes to 0 or 1 when traveling near the set value of the manual driving force. This has the effect of improving ride comfort when traveling.

Further, the invention according to claim 3 is to reduce the rate of change when entering the assist ratio rather than when exiting from the rate of change of the assist ratio so that the human-powered driving force becomes a predetermined value. In addition to assisting quickly, when exiting, the ratio is gradually reduced according to the magnitude of the manual driving force, so when the human driving force falls, there is no sudden assistance and the pedaling weight becomes heavy It has effects such as never happening.

In the invention according to claim 4, the assist ratio in the low assist ratio region is 0 or a value in the vicinity of 0, and therefore, there is an effect that the battery consumption can be suppressed in the low assist ratio region. Play.

In the inventions according to claims 5 and 6, when the low assist ratio region is released, the assist ratio is constant, for example, set to 1, so that the electric driving force is required. In some cases, sufficient assisting power can be quickly obtained, and effects such as compliance with laws in Japan can be obtained.

Further, according to a seventh aspect of the present invention, there is provided a switch for setting a plurality of assist ratios, setting a mode in which such a low assist ratio region is provided in one of the modes, and switching the mode. Alternatively, the switching is automatically performed, so that the user can appropriately set the traveling mode, and the traveling can be performed according to a request, thereby improving the usability.

The invention according to claim 8 is characterized in that the low assist ratio region is determined when the human-powered driving force increases and escapes from this region, and when the human-powered driving force decreases and enters this region. The predetermined value is made different, for example, about 100 kg · cm or more when exiting, and about 50 kg · cm or less when entering, so that the electric driving force is smaller than the value when exiting and exiting. Can be effectively assisted by the manual driving force that requires assistance, and by providing hysteresis to the set value of the human-powered torque, the assist ratio does not change frequently and the ride comfort is improved. .

[Brief description of the drawings]

FIG. 1 is a side sectional view of a driving unit according to a first embodiment of the present invention.

FIG. 2 is a plan view of the vicinity of a torque sensor of the drive unit as viewed from the side.

FIG. 3 is the same power system diagram.

FIG. 4 is a block diagram of the control circuit.

FIG. 5 is a side view showing the entire configuration.

FIG. 6 is a flowchart showing an operation of the first embodiment of the control circuit.

FIG. 7 is a graph showing a set value of an assist ratio with respect to a doujin driving force.

FIG. 8 is a graph showing a set value of an assist ratio with respect to a manual driving force according to a second embodiment of the present invention.

FIG. 9 is a graph showing a set value of an assist ratio with respect to a manual driving force according to a third embodiment of the present invention.

FIG. 10 is a graph showing a set value of an assist ratio with respect to a manual driving force according to a fourth embodiment of the present invention.

FIG. 11 is a graph showing a set value of an assist ratio with respect to a manual driving force according to a fifth embodiment of the present invention.

[Explanation of symbols]

 11 Wheel (rear wheel) 52 Torque detector (torque sensor) 39 Motor 40 Control circuit (control board) L Low assist ratio area

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masanori Kamei 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Inventor Hiroaki Sagara 2-5-2 Keihanhondori, Moriguchi-shi, Osaka No.5 Sanyo Electric Co., Ltd. (72) Inventor Toshihiro Matsumoto 2-5-5 Sanyo Electric Co., Ltd., Moriguchi-shi, Osaka (72) Inventor Seiki Inui Seiki Keihanhondori, Moriguchi-shi, Osaka 2-5-5 Sanyo Electric Co., Ltd.

Claims (8)

[Claims] 1. A human-powered driving unit that drives wheels by human power, a torque detection unit that detects a human-powered driving force of the human-powered driving unit, and an electric driving unit that drives the wheels by a motor.
A control circuit for inputting a detection value of the torque detection unit and outputting a control signal for driving the electric drive unit with a magnitude corresponding to the detection value, the control circuit comprising: A vehicle with auxiliary power, wherein a low assist ratio region is provided in which an assist ratio, which is an output ratio of an electric driving force to a manual driving force, is set to a predetermined value or less. 2. The control circuit according to claim 1, wherein the predetermined value of the manual driving force when the manual driving force is increased and the low assist ratio region is released is increased. The vehicle with auxiliary power according to claim 1, wherein the predetermined value of the driving force is different from the predetermined value. 3. The control circuit according to claim 1, wherein the change rate of the assist ratio is smaller when the human-powered driving force becomes smaller and the vehicle enters the low-assistance ratio region than when the human-powered driving force is released and the low assist ratio region is released. The vehicle with auxiliary power according to claim 1, wherein the vehicle is made smaller. 4. The vehicle with auxiliary power according to claim 1, wherein the assist ratio in the low assist ratio region is zero or a value near zero. 5. When the low assist ratio area is released,
The vehicle with auxiliary power according to claim 1, wherein the assist ratio is constant. 6. The vehicle with auxiliary power according to claim 5, wherein the assist ratio after the cancellation of the low assist ratio region is 1. 7. The control circuit according to claim 1, wherein a plurality of assist ratios, which are ratios of the electric driving force to the manual driving force, are provided in advance, and a low assist ratio region is provided in one of the assist ratios. The vehicle with auxiliary power according to 1. 8. The predetermined value of the manual driving force when the manual driving force increases and the low assist ratio region is released is 100.
3. The auxiliary power according to claim 2, wherein the predetermined value of the manual driving force is set to 50 kg.cm or less when the manual driving force is set to be at least kg.cm and the manual driving force is reduced to enter the low assist ratio region. With vehicle.