HK1054722B - Method and apparatus for automatically canceling turn signals of vehicles - Google Patents

Description

Method and apparatus for automatically canceling vehicle turn signal

Technical Field

The present invention relates to a method and a device for automatically cancelling a vehicle turn signal, such as a flashing warning light, an indicator light, etc., in particular a motorcycle turn signal.

Background

Generally, a four-wheeled vehicle such as an automobile has a function of automatically canceling a turn signal when a driver turns a steering wheel back to a normal position after the driver drives at a considerable driving angle larger than a prescribed driving angle. In contrast, in a normal situation, when a driver operates a two-wheeled vehicle such as a motorcycle, there is no function of canceling a turn signal (or an indicator lamp for indicating turning). In addition, since the motorcycle may not be equipped with other structure for automatically canceling the turn signal, basically no effective suggestion is given for the above-described function.

Therefore, the conventional motorcycle is designed to require a manual operation to cancel the turn signal after the manual operation of the turn signal. Inadvertent cancellation of the steering signal may result in unexpected problems due to driver error or may be easily forgotten to do. In other words, when the driver operates the turn signal, which should be canceled after the operation is completed, the driver may have difficulty in maintaining concentration during driving the motorcycle.

Japanese unexamined patent publication No. sho 57-155131 discloses an example of a blinker automatic canceller for motorcycles and the like using a geomagnetic sensor. According to the automatic blinker canceler, the automatic blinker is automatically cancelled under prescribed conditions, provided that a direction difference greater than a prescribed angle is detected between the steering direction and the traveling direction, and the motorcycle is returned to a straight-driving mode immediately after steering.

However, the aforementioned automatic blinker canceler requires complicated processing for detecting the return to the straight driving mode, and therefore, the canceler is expensive.

Disclosure of Invention

The object of the present invention is to provide a method and a device for automatically cancelling a motorcycle turn signal without causing an operational error, which can be manufactured at low cost.

The invention discloses a method for automatically canceling a vehicle steering signal, which comprises the following steps:

after the steering signal is operated, judging whether the direction and the inclination of the vehicle meet specified conditions;

the vehicle turn signal is automatically cancelled when the vehicle direction and the inclination satisfy prescribed conditions.

The invention also discloses a steering signal automatic cancellation device, which comprises a geomagnetic sensor for detecting the axial component of the geomagnetic (or magnetic field) and a conversion table for storing the relation between the azimuth and the inclination and the output of the geomagnetic sensor measured in advance.

Specifically, the present invention discloses a vehicle turn signal automatic canceller, including: a geomagnetic sensor for detecting geomagnetism according to an orthogonal coordinate system configured by different axes; a memory for storing a conversion table whose contents indicate a relationship among a direction measured in advance at a prescribed ground position, an inclination, and an axial output of the geomagnetic sensor; and a controller for controlling a vehicle steering signal, which is automatically canceled when the vehicle direction and the inclination satisfy prescribed conditions after the steering signal is operated.

For example, an operator or driver of a motorcycle operates a steering signal to indicate a left turn or a right turn of a traveling direction; then, when the operator tilts the motorcycle, the operator turns to the driving direction; thereafter, the operator returns the motorcycle to a normal position substantially perpendicular to the horizontal plane. In this case, after the driver operates the turn signal, the direction of the motorcycle is changed to a prescribed angle (for example, 20 °) or more, and then the inclination of the motorcycle is restored (restored) to a normal position substantially perpendicular to the horizontal plane, and the turn signal can be automatically canceled.

Therefore, it is possible to reliably avoid the occurrence of an operation error due to a mistake or negligence of the operator when the steering signal is cancelled. In addition, the present invention can be easily implemented at a relatively low cost due to its simple structure.

Drawings

These and other objects and embodiments of the invention will be described in more detail with reference to the following drawings, in which:

FIG. 1 is a block diagram of an automatic canceller for canceling a motorcycle turn signal according to an embodiment of the present invention;

FIG. 2 is a block diagram showing the detailed structure of the magnetic sensor of FIG. 1, which is shown on the X-Y axis;

FIG. 3 is a graph illustrating an example of a relationship between axial components of magnetic sensor outputs on the X-Y axis in an orthogonal coordinate system;

FIG. 4 is a rear view of a motorcycle tilted from a horizontal vertical axis;

FIG. 5 is a table showing the contents of a conversion table of the relationship among the direction, inclination, and output of the magnetic sensor on the X-Y axis;

FIG. 6 is a flow chart of the main routine of the automatic turn signal canceller; and

fig. 7 is a flowchart of a timer interrupt routine of the automatic turn signal canceller.

Detailed Description

The invention will be described in further detail by way of example with reference to the accompanying drawings.

Fig. 1 is a block diagram showing the construction of an automatic canceller for canceling a turn signal of a vehicle such as a motorcycle according to an embodiment of the present invention.

In summary, the turn signal automatic canceller is designed to detect the direction and inclination of the motorcycle based on the output of the geomagnetic sensor mounted in the motorcycle. Normally, after the driver operates the steering signal of the motorcycle, when the motorcycle is banked (or its position or spatial direction angle is leaned), the motorcycle is changed in its traveling direction, and then, the motorcycle is returned to the upright position, so that its lean (or banked) with respect to the vertical axis based on the horizontal direction is eliminated. In this case, the turn signal automatic canceller is activated to automatically cancel the turn signal of the motorcycle.

Specifically, the automatic steering signal canceller of the embodiment of the present invention, which is mounted in a motorcycle, includes: an X-Y axis magnetic sensor 5 that detects geomagnetism, an analog-to-digital (a/D) converter 6, a correction circuit 7, a decoder 8, a Read Only Memory (ROM)9, a control circuit 10, a Random Access Memory (RAM)11, a turn signal 12, a display 13, and a turn signal operating device 14. Here, two pairs of steering signals are installed on both the front and rear sides of the motorcycle, respectively, and the operator manually operates the steering signal operating device 14 when the direction is instructed to turn right or left.

The magnetic sensor 5 on the X-Y axis was originally used to detect the motorcycle direction, and it can also be used to detect the motorcycle inclination of this embodiment. Fig. 2 shows a detailed structure of the X-Y axis magnetic sensor 5 composed of a Giant Magnetoresistive (GMR) loop 50 and a voltage/magnetic field (V/Oe) switching loop 51.

The GMR circuit 50 includes a constant current bias circuit 500, an X-axis GMR unit 501 for detecting a geomagnetic X-axis component, and a Y-axis GMR unit 502 for detecting a geomagnetic Y-axis component.

The constant current bias circuit 500 supplies constant currents to both the X-axis GMR cell 501 and the Y-axis GMR cell 502 when receiving the 'on' control signal from the control circuit 10. Each of the X-axis GMR unit 501 and the Y-axis GMR unit 502 undergoes impedance changes in response to changes in the magnetic field (i.e., geomagnetism) applied thereto. Therefore, by supplying them with a constant current, a change in the magnetic field can be detected, which transformation is converted into a change in the electric potential. Specifically, when the GMR units 501 and 502 of the magnetic sensor 5 rotate on the X-Y axis, the X-axis and Y-axis components of the magnetic field applied thereto change and are detected as potential changes. Incidentally, when the motorcycle does not need to detect its direction and inclination, the control circuit 10 outputs an 'off' control signal for the magnetic sensor 5 on the X-Y axis to deactivate its operation.

The voltage/magnetic field conversion circuit 51 converts the output voltage of the GMR circuit 50 into a magnetic field value output therefrom.

The a/D converter 6 converts the analog output signal of the magnetic sensor 5 on the X-Y axis into a digital value which is supplied to the correction circuit 7. In the correction loop 7, each digital value is divided by its maximum value.

The decoder 8 detects the direction (angle) α and the inclination (angle) β based on the output of the X-Y axis magnetic sensor 5 relating to the motorcycle equipped with the turn signal automatic canceller in the present embodiment.

The direction α defined below is related to the longitudinal axis of the motorcycle body;

(a) when the longitudinal axis matches the north direction, the direction α is set to 0 or 360 degrees (deg).

(b) When the longitudinal axis matches the east direction, the direction α is set to 90 degrees (deg).

(c) When the longitudinal axis matches the southbound direction, the direction α is set to 180 degrees (deg).

(d) When the longitudinal axis matches the west direction, the direction α is set to 270 degrees (deg).

Next, detection and calculation regarding the traveling direction of the motorcycle body, which is defined by the direction α and the inclination β based on the output of the magnetic sensor 5 on the X-Y axis, will be described.

Assuming that the motorcycle is in an upright or vertical position and is rotating in a horizontal plane, the output of the magnetic sensor 5 on the X-Y axis varies in such a way that: that is, the output Vx of the X-axis GMR unit 501 varies like a sine wave, and the output Vy of the Y-axis GMR unit 502 varies like a sine wave, but is shifted by 90 ° compared to the output Vx sine wave. The coordinates of the outputs Vx and Vy therefore describe a prescribed trajectory that may correspond substantially to a solid circle with an origin 'O' in an orthogonal coordinate system (see the "solid" circle shown in fig. 3), where the horizontal axis is denoted as Vx and the vertical axis is denoted as Vy.

The geomagnetism is not always distributed horizontally on the earth, but it may be inclined to the horizontal plane at an angle corresponding to the ground position. Therefore, when the body of the motorcycle is inclined at an angle β measured from the vertical axis, a change will be caused in relation to the angle formed between the direction of the geomagnetism and the plane orthogonal to the direction perpendicular to the body, which will match the horizontal plane when the motorcycle is erected in the upright position. Due to the above-described angle change, an influence may occur in the output Vy of the Y-axis GMR cell 502. Incidentally, the X-Y axis magnetic sensor 5 is attached to a prescribed vehicle body position with respect to a prescribed plane, which position matches the horizontal plane when the motorcycle is erected in the upright position.

When the motorcycle is rotated about the vertical axis J, which is tilted (banked) by an angle β 1, the trajectory corresponding to the output coordinates of Vx and Vy will be drawn as an elliptical circle in the orthogonal coordinate system described above (see the "dash-dot line" circle in fig. 3), with the center of the "dash-dot line" circle shifted upward in the positive direction of the vertical axis (Vy) compared to the center of the solid circle described above.

When the motorcycle is rotated with the vertical axis J, which is inclined by an angle β 2 greater than β 1, the trajectory corresponding to the output coordinates of Vx and Vy will be drawn as an elliptical circle in the orthogonal coordinate system described above (see the "dotted line" circle in fig. 3), in which the smaller diameter of the dotted line circle is smaller than the smaller diameter of the dotted line circle, and the center of the dotted line circle is further moved upward in the positive direction of the vertical axis (Vy) than the center of the dotted line circle.

The coordinates (Vx, Vy) consisting of the outputs Vx and Vy can draw a definite trajectory based on the specific motorcycle direction α and inclination β, as long as the angle of the geomagnetism to the motorcycle horizontal plane, i.e., the ground position (latitude and longitude), is maintained.

Therefore, the present embodiment can be realized by preparing a conversion table storing the relationship among the direction α, the inclination β, and the coordinates (Vx, Vy) measured in an area where the motorcycle is assumed to be located with the geomagnetic inclination substantially kept unchanged, which is stored in the ROM 9.

With reference to the conversion table stored in the ROM9, it is possible to determine the motorcycle direction α and the inclination β in relation to the coordinates (Vx, Vy).

In the above description it is possible to measure the direction and tilt (α, β) of two or more pairs relating to the same coordinates (Vx, Vy), an embodiment of which is shown by the point K in fig. 3. In this example, a plurality of pairs of directions and inclinations (α, β) are measured in a prescribed range of assumed (or possible) use states of the motorcycle, and the average value is used for the conversion table. Here, the prescribed range of the assumed use state of the motorcycle may be set such that the direction α is in the range of 0 to 360(deg) and the inclination β is in the range of 0 to 45 (deg). An example of the contents of the translation table is shown in FIG. 5.

In fig. 1, the ROM9 stores various types of control programs and fixed data, and the ROM9 also stores a conversion table showing the relationship between the direction (α) and the inclination (β) with respect to the values vx (oe) and vy (oe) that is generated by the normal output of the magnetic sensor 5 on the X-Y axis shown in fig. 5.

The decoder 8 detects the traveling direction of the motorcycle, i.e., the direction α and the inclination β, with reference to the above-described conversion table.

Using the conversion table of fig. 5, it is possible to detect the direction α and the inclination β at the smallest change angle (see the numbers of the bottom lines in fig. 5). Therefore, the decoder 8 performs decoding to generate a direction and a tilt within a prescribed range of Vx and Vy values shown in the conversion table.

The control circuit 10 executes a control program stored in the ROM9, thereby controlling various programs of the turn signal automatic canceller in fig. 1.

The display 13 is constituted by a liquid crystal display for displaying different data on a screen, for example, wherein the display displays the detected direction and inclination of the motorcycle body.

The turn signal operating device 14 has a turn signal button (or lever) 14a that the driver can activate right or left turn signals (i.e., turn signals 12) to issue a blinker alert to the right or left. In addition, the driver can press the turn signal button 14a to turn off the turn signal 12, i.e., the present embodiment allows the driver to cancel the turn signal 12.

Next, the entire operation of the turn signal automatic canceller of the present embodiment will be described with reference to flowcharts shown in fig. 6 and 7. Fig. 6 is a flowchart showing a main routine executed when the power is turned on, and fig. 7 is a flowchart showing a timer interrupt routine executed periodically in each prescribed cycle. The main routine of fig. 6 is initiated when the driver inserts a key into the ignition switch of the motorcycle to start the engine and turn on the power, whereupon initialization (or initialization settings) relating to various factors and parameters are automatically performed at step 100. In step 101, a timer included in the control loop 10 is started, and thus the timer interrupt routine of fig. 7 is automatically started at every prescribed time measured by the timer.

In step 102, a determination is made as to whether an indicator event has occurred, in other words, a determination is made as to whether a driver has operated the turn signal button 14a of the turn signal operating device 14. If no indicator light event is indicated to occur 'NO', the turn signal automatically cancels the same decision that step 102 is repeated. If the indicator light event occurrence 'yes' is indicated, the flow proceeds to step 103 where a determination is made as to whether the driver has turned on the turn signal 12, in other words, whether the driver has operated the turn signal button 14a to the right or left.

If yes in step 103, the 'indicator light' flag is set to '1' in step 104; next, the flow proceeds to step 105, in which in response to the operation of the turn signal knob 14a, turning to the right or left, the traveling direction of the motorcycle (i.e., the direction relating to the vertical axis of the motorcycle body) α measures a value of α 0, which is stored in the register 'direction' of the RAM 11. Thereafter, the flow proceeds to step 106.

From the above, the marking indicator lamp is used to indicate whether the driver turns the turn signal button 4a to the right or left.

If 'NO' in step 103, the flag indicator is reset to '0' in step 107; the flow then proceeds to step 106. In step 106, a determination is made as to whether the ignition switch is turned off. If 'no', the flow returns to step 102. If 'yes', the turn signal automatic canceller ends the main routine.

Next, the timer interrupt routine will be described in detail with reference to fig. 7. When the timer interrupt routine of fig. 7 is started, the flow first proceeds to step 200, in which the decoder 8 detects the direction α and the inclination of the motorcycle body based on the outputs Vx, Vy references of the X-Y axis magnetic sensor 5, the conversion table stored in the ROM9, and thus the detected values are stored in the RAM 11.

In step 201, the current detection values of the direction α and the inclination β are displayed on the screen of the display 13. In step 202, a determination is made as to whether the flag indicator light is set to '1'.

A change in direction Δ α (═ α 0- α |) is detected between the initial direction α 0 and the current direction α detected at the current time, where α 0 is a detected value when the driver operates the turn signal button 14 a. In step 203, a determination is made as to whether the change in direction Δ α exceeds a prescribed angle of 20 °. If 'yes', the flag 'Cancel' is set to '1' in step 204. Then the flow proceeds to step 205.

As described above, the flag cancellation is used to determine whether the required condition for canceling the turn signal 12 (i.e., the required condition for canceling the turn signal 12) is satisfied. If 'No' in step 203, the flow proceeds to step 205.

In step 205, a determination is made whether to unset the flag to '1'. If 'yes', the flow proceeds to step 206, where a decision is made as to whether or not the motorcycle body inclination β detected in step 200 falls within the prescribed range-3 ° < β < 3 °, in other words, a decision is made as to whether or not the motorcycle has completely finished turning its traveling direction and returning to the normal position perpendicular to the horizontal plane, so as to return to the inclination β which it had increased. If 'yes' in step 206, the turn signal automatic canceller automatically cancels the turn signal 12 in step 207. In step 208, both the flag indicator light and the flag cancellation are reset to zero; after that, the timer interrupt routine in fig. 7 is ended.

Incidentally, when the decision of step 205 or the decision of step 206 is no; the timer interrupt routine is ended. Therefore, the timer interrupt routine consisting of steps 200 to 208 is periodically executed in every prescribed cycle.

The above-mentioned values 20 °, -3 °, and 3 ° are used in step 205 of determining Δ α and in step 206 of determining β, which are merely exemplary and not limiting; it is therefore possible to use optimum values which can be determined, for example, by experimentation.

The automatic steering signal canceller of the present embodiment used in a motorcycle may be designed in such a manner that the direction and inclination of the motorcycle body are detected based on the output of a magnetic sensor of the X-Y axis installed in the motorcycle body, wherein when the traveling direction of the motorcycle is changed according to the operation of the steering signal, then, the inclination of the motorcycle body is returned to the normal position perpendicular to the horizontal plane, and the steering signal is automatically cancelled. Therefore, it is possible to avoid an operational error occurring in canceling the turn signal, and it can be manufactured at a relatively low cost due to the simple structure of the turn signal automatic canceller.

Specifically, the turn signal automatic canceller needs to use a single geomagnetic sensor in detecting the direction and inclination of the motorcycle with respect to the traveling direction. Here, the steering signal automatic canceller may perform determination regarding return to the normal position, which is established when the motorcycle has completely finished steering the traveling direction based on the change in the direction and inclination of the motorcycle, so that the steering signal can be reliably cancelled according to the determination described above.

As described so far, the present invention has various technical features and effects, and will be described below:

(1) the steering signal automatic canceller is constituted using a single geomagnetic sensor employed in detecting the direction and inclination of the motorcycle, wherein the steering signal is automatically cancelled according to prescribed conditions concerning changes in the direction and inclination of the motorcycle. Specifically, a conversion table measured in advance showing the relationship between the direction, inclination, and output of the geomagnetic sensor is used to detect the direction and inclination of the motorcycle at any ground position.

(2) As described above, the direction and inclination of the motorcycle are detected in response to the output of the geomagnetic sensor installed in the body of the motorcycle, wherein when the motorcycle is changed in the traveling direction according to the operation of the turn signal, then, the motorcycle is restored to the normal position substantially perpendicular to the horizontal plane, and the turn signal is automatically canceled.

(3) Specifically, the direction and inclination of the motorcycle are detected with reference to the conversion table, wherein after the driver operates the turn signal, the direction of the motorcycle can be changed by a prescribed angle or more, and then the motorcycle is returned to a normal position substantially perpendicular to the horizontal plane, and the turn signal is automatically canceled.

As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, the present embodiments are therefore illustrative and not restrictive, since the scope of the invention is defined by the appended claims rather than by the description preceding them, and all changes that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims (9)

1. A method of automatically canceling a turn signal of a vehicle, wherein the vehicle is a motorcycle, and wherein a tilt of the motorcycle is changed when a driving direction of the motorcycle is changed, the method comprising the steps of:

after the steering signal is operated, judging whether the direction and the inclination of the vehicle meet specified conditions;

the vehicle turn signal is automatically cancelled when the vehicle direction and the inclination satisfy prescribed conditions.

2. The method for automatically canceling a vehicle turn signal according to claim 1, wherein the prescribed condition specifies that: that is, the vehicle is changed in the vehicle traveling direction according to the operation of the turn signal, and thus the vehicle direction is changed by a prescribed angle or more accordingly, and then the vehicle inclination is restored to a normal position perpendicular to the horizontal plane.

3. The method of automatically canceling a vehicle turn signal according to claim 1, wherein the vehicle direction and inclination are detected using a geomagnetic sensor.

4. The method of automatically canceling a vehicle turn signal according to claim 1, wherein the vehicle direction and inclination use a conversion table whose contents are based on a geomagnetic sensor axial output prepared in advance.

5. The method of automatically canceling a vehicle turn signal according to claim 1, characterized in that the prescribed condition is described in such a way that: when the traveling direction of the vehicle is changed after the steering signal is operated, the vehicle direction is changed beyond a prescribed angle, and then the vehicle inclination is restored within the range of the prescribed angle.

6. An automatic vehicle turn signal canceller, comprising: a geomagnetic sensor (5) for detecting geomagnetism according to an orthogonal coordinate system configured by different axes; a memory (9) for storing a conversion table whose contents represent the relationship among the direction measured in advance at a prescribed ground position, the inclination, and the geomagnetic sensor axial output; and a controller (10) for controlling a vehicle turn signal (12) that is automatically canceled when the vehicle direction and the inclination satisfy prescribed conditions after the turn signal is operated.

7. The vehicle turn signal automatic canceller according to claim 6, wherein the prescribed condition specifies that: that is, the vehicle is changed in the vehicle traveling direction according to the operation of the turn signal, and thus the vehicle direction is changed by a prescribed angle or more accordingly, and then the vehicle inclination is restored to a normal position perpendicular to the horizontal plane.

8. The vehicle turn signal automatic canceller according to claim 6, wherein the vehicle is a motorcycle, and the inclination of the motorcycle is changed when the traveling direction of the vehicle is changed.

9. The vehicle turn signal automatic canceller according to claim 6, characterized in that the prescribed condition is described in such a manner that: that is, when the direction of travel of the vehicle is changed beyond a prescribed angle after the steering signal is operated, the vehicle inclination is restored within the range of the prescribed angle.