JP2004093537A - Fall down detection device of motorcycle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fall down detection device of a motorcycle capable of improving an accuracy for fall down determination by reducing the A/D conversion error of a fall down sensor formed of an acceleration sensor. <P>SOLUTION: This fall down detection device of the motorcycle comprises an ECU drivingly controlling an engine and the fall down sensor detecting the fall down based on the inclination angle of a body. The fall down sensor is formed of the acceleration sensor, and the acceleration sensor is incorporated in the ECU. In the acceleration sensor 1, the detecting direction (ab) of accelerations when the body is in the non-inclined state (θ = 0) is set vertical to the ground, and used as a first detecting direction. Then accelerations in the first detecting direction and a second detecting direction perpendicular to the first detecting direction are detected. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a motorcycle fall detection device using an acceleration sensor.
[0002]
[Prior art]
A motorcycle is provided with an ECU (engine control unit) for fuel injection control and ignition timing control. The ECU drives and controls the injector and the ignition coil according to a preset map or control program based on engine speed detection data, throttle opening detection data, or intake pipe negative pressure detection data. Such an ECU has a semiconductor element such as a storage circuit in which maps and programs are stored and an arithmetic circuit for performing data processing mounted on a printed circuit board, and is mounted on a vehicle body in a unitized state as one component. .
[0003]
In addition, a fall sensor is provided in the motorcycle to stop fuel injection and ignition when a fall of the vehicle body is detected, and to stop fuel supply when the engine is stopped by stopping a fuel supply electromagnetic pump.
[0004]
A conventional fall sensor has a mechanical structure that uses a weight or a pendulum that moves according to the inclination of the vehicle body, and that the weight or the pendulum turns on a switch when the vehicle falls. A fall sensor having such a mechanical structure is attached to a vehicle body as a separate body from the ECU, and sends fall detection data to the ECU, and the ECU performs engine control when the fall occurs based on the detection data.
[0005]
However, the conventional mechanical fall sensor has an insufficient surface in terms of detection accuracy and reliability. Therefore, in order to improve the accuracy and reliability by improving this, it is necessary to prevent the contact failure of the switch and to smoothly operate the weight and the pendulum. For this reason, it is necessary to perform a plating process or to have a stepless structure, and the manufacturing process is troublesome, which causes a cost increase. In addition, the size and weight are large, and this is a space constraint for other components.
[0006]
Further, in the conventional ECU mounting structure, since the ECU and the overturning sensor are separate bodies, when used in a small scooter or the like in which the space around the engine is narrow, the space restriction is great. In addition, since the conventional body tilt sensor uses a mechanical pendulum structure, it is large and complicated in configuration, and it is perpendicular to the ground and in the front and rear direction of the vehicle so that the pendulum can move smoothly in the left and right direction of the vehicle. It had to be installed vertically, the layout was complicated and installation was troublesome.
[0007]
On the other hand, an acceleration sensor using a semiconductor element is known. In this acceleration sensor, a capacitor is formed between electrodes, and the capacitance is changed according to the acceleration to detect the magnitude of the acceleration. This acceleration sensor does not have a large mechanical configuration other than the electrodes, and can obtain highly accurate acceleration detection data in the form of a semiconductor element. Therefore, if the acceleration sensor detects the gravitational acceleration, the inclination of the sensor can be detected.
[0008]
Therefore, it has been proposed and known by the present inventor to use this acceleration sensor as a fall sensor and to integrate it into an ECU (for example, see Patent Document 1).
[0009]
The acceleration sensor has a detection direction for detecting acceleration, a one-axis sensor detects acceleration in one direction, a two-axis sensor detects acceleration in two orthogonal directions, and a three-axis sensor detects three directions in orthogonal. , The acceleration is respectively detected. When this acceleration sensor is incorporated in the ECU as a fall sensor, and this ECU is mounted on the vehicle body, the detection direction of the acceleration sensor for one axis is vertically arranged with respect to the vehicle body (vertical direction to the ground), or the vehicle is mounted vertically. On the other hand, it is considered that the acceleration when the vehicle body is tilted can be efficiently detected by adopting any one of the horizontal arrangements in the left-right direction (vehicle width direction).
[0010]
Such an acceleration sensor outputs an analog voltage as a detection voltage according to the inclination of the vehicle body. The analog detection voltage is A / D converted, and is input as a digital signal to a control circuit (CPU) in the ECU to determine a falling state.
[0011]
[Patent Document 1]
JP 2002-71703 A
[0012]
[Problems to be solved by the invention]
However, when the acceleration sensor is used as a fall sensor and a fall is determined from the detection signal, a conversion error based on the A / D conversion width occurs when the detection signal is A / D converted to determine the fall. Therefore, there is a possibility that a detection error of the overturning angle occurs due to the conversion error and an erroneous determination is made.
[0013]
SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-described conventional technology, and has as its object to provide a motorcycle fall detection device that reduces an A / D conversion error of a fall sensor including an acceleration sensor and improves the accuracy of fall determination.
Further, the present invention provides a motorcycle fall detecting device which can be easily mounted and reduced in size, simplifies the configuration and layout of parts around the engine, and can be efficiently laid out in a narrow space without restricting the arrangement of other parts. For the purpose of providing.
[0014]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides an ECU that controls driving of an engine and a fall sensor that detects a fall based on a lean angle of a vehicle body, wherein the fall sensor is configured by an acceleration sensor, and the acceleration sensor is the ECU. In the motorcycle fall detection device incorporated in the vehicle, the acceleration sensor arranges a detection direction of acceleration when the vehicle body is not tilted in a direction perpendicular to the ground and sets this as a first detection direction. A fall detection device for a motorcycle, characterized by detecting acceleration in a second detection direction perpendicular to the first detection direction as well as the first detection direction.
[0015]
According to this configuration, the acceleration sensor is used as a fall sensor, which is incorporated in the ECU to form an integrated unit, thereby improving the fall detection accuracy and simplifying the configuration, and restricting the arrangement of other components. It can be laid out efficiently in a narrow space. At the same time, the acceleration sensor is arranged vertically, that is, the acceleration detection direction when the vehicle body is not tilted is set to be perpendicular to the ground, so that the vehicle falls over or over the bank angle. In this case, the change in the detection output with respect to the change in the inclination angle in the vicinity of the bank angle (65 to 70 °), which is the discrimination angle of the overturning state, is large. Therefore, the change in the angle within a fixed A / D conversion output width is small. In addition, the conversion error can be reduced, and the accuracy of the fall determination can be improved and the reliability can be improved.
[0016]
In addition, a two-axis or three-axis acceleration sensor is used, and one axis is always set to the vertical detection direction (first detection direction), and the acceleration in the second detection direction in the vehicle width direction or the front-back direction is detected. Accordingly, when the angle of the first detection direction exceeds the falling angle, the inclination of the vehicle body due to wheely running or running on a slope is erroneously determined to be a fall based on the detection result in the second detection direction. Is prevented.
[0017]
In a preferred configuration example, the acceleration in the first detection direction is detected based on a difference from a preset reference value in a non-inclined state, and the acceleration in the second detection direction is calculated based on a change amount of the acceleration. It is characterized by detecting.
[0018]
According to this configuration, for the first detection direction, the inclination angle of the vehicle body is determined based on the difference from the reference value obtained by correcting the offset error of the detection data based on the attachment error and the like, and the inclination angle of the vehicle body other than falling due to wheely running or the like is determined. With respect to the second detection direction for determining the inclination, it is possible to identify whether the vehicle has fallen or a wheely by determining whether there is a change in the inclination. Therefore, it is not necessary to calculate the difference from the reference value. The correction of the offset error of the reference value becomes unnecessary.
[0019]
In a further preferred configuration example, a threshold value for judging a fall in the first detection direction is changed based on a mounting angle of the acceleration sensor.
[0020]
According to this configuration, when the ECU incorporating the acceleration sensor is attached to the vehicle body in an inclined manner with respect to the vertical direction of the vehicle body due to an error in mounting the ECU on the vehicle body, the threshold value for judging the fall according to the angle of inclination is provided. , The detection accuracy can be increased. In this case, the left and right inclination directions are determined from the output of the second detection direction, and the threshold value is changed according to the left and right directions.
[0021]
In a further preferred configuration example, the average detected value of the acceleration sensor when the running speed is equal to or more than a certain value and the amount of change in the detection output of the acceleration sensor is equal to or less than a certain value is stored as a center value, and the center value falls as the reference value. It is characterized by judgment.
[0022]
According to this configuration, when the traveling speed is equal to or more than a certain value and the output change of the acceleration sensor is equal to or less than a certain value, it is determined that the vehicle is traveling in a straight posture with almost no inclination, and the average value of the sensor output at this time is determined. Is stored as the center value. By detecting a change from the center value, it is possible to prevent a decrease in detection accuracy due to a variation in offset due to a temperature characteristic of the sensor or an installation error, or a change with time.
[0023]
In a further preferred configuration example, a sensor in a vertical direction and a sensor in a horizontal direction are provided, and a fall is determined based on (horizontal sensor output) ÷ (vertical sensor output).
[0024]
According to this configuration, even if the output value of the fall detection fluctuates due to the vibration of the vehicle body or the like, a highly reliable fall detection without erroneous determination can be performed in a short time without using a noise removing filter or the like.
[0025]
That is, when an acceleration sensor is used as a fall sensor for a motorcycle, the fall detection angle serving as a threshold value for fall determination may change due to vibration of the vehicle body or the like. In response to this, a filter is provided in the control circuit to remove the vibration component, so that the fall detection angle can be kept constant. However, when the filter is provided, the response time is long, the detection time is long, and there is a possibility that the handling of the fall is delayed.
[0026]
Therefore, there is a need for a fall sensor capable of eliminating a change in a fall detection angle due to vehicle body vibration or the like without prolonging the detection time and performing fall detection without erroneous determination. The present invention also satisfies such a need.
[0027]
In a further preferred configuration example, the tipping sensor comprises a two-dimensional acceleration sensor, the tipping sensor is housed in the ECU, and the ECU is set so that the detection surface of the tipping sensor is substantially perpendicular to the vehicle longitudinal direction. It is characterized by being attached to the body frame.
[0028]
According to this configuration, a two-dimensional (two-axis) acceleration sensor is used as a fall sensor incorporated in the ECU, and the two-dimensional detection surface is disposed substantially perpendicular to the front-rear direction of the vehicle body, and the ECU is mounted on the vehicle body frame. , It is securely fixed to the vehicle body, and the reliability of mounting and detection is improved. In addition, the degree of freedom in mounting can be increased by, for example, mounting the ECU accommodating the tipping sensor on the vehicle body frame with a slight inclination in the front-rear direction corresponding to the surrounding component arrangement space, thereby facilitating component arrangement.
[0029]
In a further preferred configuration example, the ECU is provided at a central portion of the vehicle body in the left-right direction.
[0030]
According to this configuration, it is possible to similarly detect with a high degree of accuracy even if the vehicle falls in the left or right direction, the reliability of the fall detection is enhanced, and the vehicle is mechanically protected by the body frames on both the left and right sides when the vehicle rolls over. Damage is prevented.
[0031]
In a further preferred configuration example, a fuel tank mounting bracket is fixed to a vehicle body frame member disposed on the left and right of the vehicle body central portion, the ECU is disposed between these left and right brackets, and each bracket is provided with a stay via a stay. It is characterized in that the ECU is fixed.
[0032]
According to this configuration, the left and right brackets for mounting the fuel tank in the center of the vehicle body can be used to efficiently arrange the ECU between these brackets in a space-efficient manner. The distance to various engine and driving parts such as sensors, injectors, throttle valves and ignition coils is shortened, so that the wiring harness including the signal cable and the like can be shortened, and the layout around the engine is simplified.
[0033]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an explanatory diagram of the sensor output when the one-axis acceleration sensor is arranged horizontally. (A) is an output waveform, (B) is an explanatory diagram of a state in which the vehicle body is inclined to the right by an angle θ.
[0034]
The acceleration sensor 101 is mounted on the vehicle body in a horizontal arrangement in which the detection direction ab is horizontally arranged in a non-inclination state (neutral position) where the vehicle body is straight. Therefore, the sensor output becomes the output voltage V = g · sin θ with respect to the inclination angle θ of the vehicle body, and the output voltage characteristic draws a sine curve as shown in FIG. The motorcycle is considered to be overturned when the vehicle body is tilted beyond the bank angle (about 65 to 70 °), and if over 70 ° is used as a criterion, it can be determined that the motorcycle has overturned. Therefore, if the sensor output at 70 ° as the determination reference is the determination output Vc,
Vc = g · sin 70 ° = 0.94 g.
[0035]
Here, when the A / D conversion error is ± 10 mV (± 0.03 g), the angle error is (0.94-0.03) g ≒ g · sin 65 °
(0.94 + 0.03) g ≒ g · sin75 °
It becomes. Therefore, the angle error based on the A / D conversion is 70 ± 5 °.
[0036]
FIG. 2 is an explanatory diagram of the sensor output when the one-axis acceleration sensor is vertically arranged. (A) is an output waveform, (B) is an explanatory diagram of a state in which the vehicle body is inclined to the left by an angle θ.
[0037]
The acceleration sensor 101 is attached to the vehicle body in a vertical arrangement in which the detection direction ab is perpendicular to the ground in a non-inclined state (neutral position) in which the vehicle body is straight. Therefore, the sensor output becomes the output voltage V = g · cos θ with respect to the inclination angle θ of the vehicle body, and the output voltage characteristic draws a cosine curve as shown in FIG. The motorcycle is considered to be overturned when the vehicle body is tilted beyond the bank angle (about 65 to 70 °), and if over 70 ° is used as a criterion, it can be determined that the motorcycle has overturned. Therefore, if the sensor output at 70 ° as the determination reference is the determination output Vc,
Vc = g · cos 70 ° = 0.34 g.
[0038]
Here, when the A / D conversion error is ± 10 mV (± 0.03 g), the angle error is (0.34-0.03) g ≒ g · cos 72 °.
(0.34 + 0.03) g ≒ g · cos 68 °
It becomes. Therefore, the angle error based on the A / D conversion is 70 ± 2 °.
[0039]
That is, at a tilt angle of around 70 ° serving as a criterion for determining a fall, the angle error based on the A / D conversion in the case of the vertical installation shown in FIG. Therefore, in the present invention, when a one-axis acceleration sensor is used, by vertically disposing the sensor (Z direction), an A / D conversion error can be reduced and detection accuracy can be improved. When a two-axis (Y, Z direction) or three-axis (X, Y, Z direction) acceleration sensor is used, one detection direction (first detection direction) is always set vertically (Z direction), The second detection direction is a horizontal vehicle width direction (Y direction) or a front-rear direction (X direction).
[0040]
When a two-axis or three-axis acceleration sensor is used, when the sensor in the Z direction detects an inclination greater than the falling angle, and when the sensor in the X direction or the Y direction does not detect the inclination, wheely driving or steep hill driving is performed. Assuming that the vehicle is overturned (fuel pump stop, fuel injection stop, ignition stop, etc.), the vehicle continues traveling under normal control.
[0041]
The detection direction of the two-axis acceleration sensor is set to the Z and X directions, and when the detection output in the X direction changes (when the inclination in the front-rear direction is detected), it is possible to judge that the road is a steep slope or a wheelie and not to regard it as a fall. is there.
[0042]
FIG. 3 is a flowchart of a control example of the overturning device according to the present invention.
In this embodiment, the fall is determined only by detecting one axis (Z-axis direction) of the sensor.
Step a1: An output voltage is detected from a tipping sensor in which a one-axis acceleration sensor is vertically arranged, or from a sensor in a Z-axis direction which is a first detection direction in a vertically arranged two-axis or three-axis acceleration sensor.
[0043]
Step a2: It is determined whether or not the vehicle has fallen according to the detection output voltage of the Z-axis direction sensor. That is, it is determined whether or not the state is smaller than the output voltage value (g · cos (± 70 °)) corresponding to ± 70 °, which is the overturn determination reference angle, in the cosine curve of FIG. If this state continues for 2 seconds or more, it is determined that the vehicle has fallen. The reason that the condition is to be continued for 2 seconds or more is to enhance the reliability of the fall judgment by the voltage detection.
[0044]
Step a3: If it is determined that the vehicle has fallen, the fuel pump is stopped, fuel injection and ignition are stopped, and the engine is stopped. At this time, it is desirable to gradually reduce the engine output. For example, the application of the drive pulse signal to the ignition coil in the ignition cycle by the normal control is stopped at an appropriate interval to control the thinning of the ignition, and the output is reduced by reducing the number of times of the ignition by the normal control. At this time, the thinning interval at which the ignition is stopped is such that the ignition is cut at a long interval at first and thinned so that the interval is gradually shortened. This prevents the vehicle body from becoming unstable due to a sudden drop in output in the case of a malfunction or the like. Instead of or in addition to such ignition control, the fuel injection may be similarly thinned out. In this case, the application of the drive pulse signal to the solenoid of the injector is gradually reduced to reduce the output. In the case of a vehicle equipped with an electronic throttle, the output may be reduced by controlling the electronic throttle.
[0045]
FIG. 4 is a flowchart of another control example of the overturn control device according to the present invention.
This embodiment uses the outputs from the detection sensors of the two axes (Y-axis direction and Z-axis direction), and in addition to the fall judgment based on only the Z-axis sensor in the embodiment of FIG. The judgment condition is added. Thereby, the inclination of the vehicle body due to the wheely running or the steep running can be distinguished from the overturn and determined.
Step b1: The two-axis acceleration sensor is arranged vertically, and the detection directions are defined as a Z axis (vertical direction) and a Y axis (horizontal direction). The output voltage of the acceleration sensor is detected in the Z-axis and Y-axis directions.
[0046]
Step b2: It is determined whether or not the vehicle has fallen according to the detection output voltage of the Z-axis direction sensor. That is, it is determined whether or not the state is smaller than the output voltage value (g · cos (± 70 °)) corresponding to ± 70 °, which is the overturn determination reference angle, in the cosine curve of FIG. If this state continues for 2 seconds or more, it is determined that the vehicle has fallen. Note that, as described above, the requirement that the continuation lasts for 2 seconds or more is to increase the reliability of the fall judgment by voltage detection.
[0047]
Step b3: If it is determined in step b2 that the sensor in the Z-axis direction has fallen, it is further determined whether or not the vehicle has fallen according to the detection output voltage of the Y-axis direction sensor. That is, in the sine curve of FIG. 1A described above, the output voltage value (g · sin (70 °)) corresponding to ± 70 °, which is the overturning determination reference angle, or (g · sin (−70 °)). )) It is determined whether the state is smaller. If this state continues for 2 seconds or more, it is determined that the vehicle has fallen.
[0048]
Even if it is determined that the vehicle has fallen in step b2, if the Y-axis sensor detects that the vehicle is not tilted in the left-right direction, the vehicle body is tilted in the front-rear direction by a wheelie or the like. repeat.
[0049]
Step b4: If it is determined that the vehicle has fallen, the fuel pump is stopped, fuel injection and ignition are stopped, and the engine is stopped. At this time, it is desirable to gradually reduce the engine output as described above.
[0050]
FIG. 5 is a block diagram of another embodiment of the present invention.
In this embodiment, when a two-axis or three-axis acceleration sensor is used, the input to the CPU for discriminating a fall is divided into two systems, a DC input and an AC input.
[0051]
As shown in the drawing, the Z-axis output from the Z-axis sensor of the two-axis acceleration sensor 2 is input to the A / D converter 4 via the noise removing filter 3, where it is A / D converted and converted into the CPU 7 in the ECU. The falling state is determined by arithmetic processing. This system is a DC input system.
[0052]
On the other hand, the Y-axis output from the Y-axis sensor of the two-axis acceleration sensor 2 is input to the A / D converter 4 via the smoothing capacitor 5 and the filter 6, where it is A / D converted and The data is input to the CPU 7 and the fall state is determined by the arithmetic processing. This system is an AC input system.
[0053]
The Y-axis sensor is an auxiliary sensor for performing a wheely determination or the like as described above to prevent a malfunction. Therefore, it is sufficient to determine whether the vehicle body has tilted from a straight state during traveling. Therefore, the input from the Y-axis sensor to the CPU is determined as an AC input, such as a wheelie, based on the amount of change in the output voltage. This eliminates the need to compare the output voltage with the first reference value and find the difference between the output voltage and the first reference value.
[0054]
FIG. 6 is a flowchart showing the operation of the fall detecting device of FIG.
Step c1: The two-axis acceleration sensor is arranged vertically, and the detection directions are defined as a Z axis (vertical direction) and a Y axis (horizontal direction). The output voltage of the acceleration sensor is detected in the Z-axis and Y-axis directions.
[0055]
Step c2: It is determined whether or not the vehicle has fallen according to the detection output voltage of the Z-axis direction sensor. That is, it is determined whether or not the state is smaller than the output voltage value (g · cos (± 70 °)) corresponding to ± 70 °, which is the overturn determination reference angle, in the cosine curve of FIG. If this state continues for 2 seconds or more, it is determined that the vehicle has fallen. Note that, as described above, the requirement that the continuation lasts for 2 seconds or more is to increase the reliability of the fall judgment by voltage detection.
[0056]
Step c3: If it is determined in step c2 that the sensor in the Z-axis direction has fallen, it is further determined whether or not the sensor has fallen according to the detection output voltage of the Y-axis direction sensor. In this case, it is determined whether or not the output voltage of the horizontally placed Y-axis sensor has changed by a predetermined value (for example, 200 mV) in the sine curve of FIG. 1A, and the difference from the neutral position is not determined. If there is no change in the inclination in the lateral direction (horizontal direction of the vehicle body) (if it is 200 mV or less), the fall detection in the above step c2 is the inclination of the vehicle body in the front-rear direction by the wheelie or the like. The normal control routine is repeated.
[0057]
Step c4: If it is determined that the vehicle has fallen, the fuel pump is stopped, fuel injection and ignition are stopped, and the engine is stopped. At this time, it is desirable to gradually reduce the engine output as described above.
[0058]
FIG. 7 is an explanatory diagram of still another embodiment of the present invention.
In this embodiment, the threshold of the detection voltage of the acceleration sensor is changed to prevent the detection accuracy from being lowered due to the mounting error of the acceleration sensor.
[0059]
This involves first measuring the mounting error angle of the acceleration sensor, and changing the threshold value by that angle based on the measured angle. For the measurement of the mounting error angle, in the case of a horizontal sensor, the sensor output is measured at three points of -90 °, 0 °, and + 90 °, and the mounting error angle is obtained from the measurement result by arithmetic processing. In the case of a vertical sensor, the sensor output is measured at three points of 0 °, 90 °, and 180 °, and the mounting error angle is obtained from the measurement result by arithmetic processing.
[0060]
The arithmetic processing will be described by taking a horizontal arrangement as an example.
At −90 °: Y = a + Xsin (−90 + b) = a−Xcos (b)
At 0 °: Y ′ = a + Xsin (b)
At + 90 °: Y ″ = a + Xsin (90 + b) = a + Xcos (b)
Here, Y, Y ', and Y "indicate the output voltage, a indicates the offset voltage, X indicates the sensitivity, and b indicates the sensor inclination (mounting error accuracy).
[0061]
Here, from Y + Y ″ = 2a, a = (Y−Y ″) / 2
X = (Y ″ −Y) / 2cos (b) from Y ″ −Y = 2Xcos (b)
Y′−a = Xsin (b) = (Y ″ −Y) / {2cos (b) * sin (b)}
2cos (b) * sin (b) = sin (2b) = (Y "-Y) / (Y'-a)
Therefore, b = 1/2 * sin ^-1 {(Y ″ −Y) / (Y′−a)}.
[0062]
The threshold value of the fall determination is changed based on the inclination angle b thus obtained.
In the example of FIG. 7, in the horizontal sensor, when b is inclined by + 5 °, the threshold value is changed from ± 70 ° to −65 ° and + 75 °. In the case of a vertical sensor (in the case of a vertical sensor (Z-axis sensor) of a two-axis acceleration sensor), the left-right inclination direction can be determined from the Y-axis sensor, and the threshold value can be changed according to the left-right direction. .
[0063]
FIG. 8 is an explanatory diagram of still another embodiment of the present invention.
In this embodiment, when checking the mounting position of the acceleration sensor 110 on the printed circuit board 111, markings 108 and 109 are made in advance on the sensor mounting position of the printed circuit board 111 so that visual or automatic checking can be easily performed. It was done. The markings 108 and 109 are formed at positions where the inclination of the acceleration sensor 110 is allowable and the mounting angle is a standard. The marking shape is not limited to (A) and (B) in the drawing, and may be any shape as long as the angle can be roughly identified.
[0064]
By performing such marking, an attachment error of the acceleration sensor with respect to the printed circuit board is identified, and the fall determination can be corrected based on this, and the defective product can be easily determined.
[0065]
The printed circuit board that constitutes the CPU by mounting the acceleration sensor in this manner is housed in the case of the ECU. In this case, a guide is provided on the ECU case, the printed circuit board is slid along the guide, inserted into the case, positioned, filled with resin, etc., and the printed circuit board is fixed at the predetermined predetermined position in the case. It is desirable to keep. This reduces detection errors due to mounting errors of the printed circuit board with respect to the ECU.
[0066]
When an ECU having a built-in fall sensor is mounted on a vehicle body, if the ECU is separated from the center of gravity of the vehicle body, the vibration of the vehicle body affects the fall sensor, lowering the detection accuracy and causing erroneous determination.
[0067]
Therefore, in order to improve the detection accuracy, it is desirable that the ECU be mounted as close to the center of gravity of the vehicle as possible. As a result, noise factors due to the influence of the vibration of the vehicle body and the longitudinal pitch can be reduced, and the detection accuracy can be increased.
[0068]
FIG. 9 is a flowchart of still another embodiment of the present invention.
This embodiment corrects the fall sensor using a speed sensor in response to the problem that the detection accuracy has been reduced due to the offset variation of the fall sensor, aging, temperature characteristics, and the like, which has been a problem in the past. Thereby, the detection accuracy is improved.
[0069]
Step d1: The vehicle speed is detected by a speed sensor, and the inclination of the vehicle body is detected by a fall sensor (acceleration sensor).
[0070]
Step d2: It is determined whether or not the state where the detection value of the speed sensor exceeds a predetermined value (30 km / h in this example) and the output voltage change of the tipping sensor is less than a predetermined value (10 mV in this example) for 10 seconds or more. I do. If this state continues for 10 seconds or more, it is determined that the vehicle is traveling in a straight posture.
[0071]
Step d3: When it is determined in step d3 that the vehicle is traveling in a straight posture, the output of the tipping sensor or its average value is updated as the center value (the output voltage value at the neutral position in FIGS. 1 and 2). save.
[0072]
Step d4: A change from the center value is detected to determine whether or not the vehicle has fallen (the inclination is 70 ° or more). As a result, the fall can be detected with high accuracy irrespective of the variation in the offset due to the temperature characteristic of the sensor or the mounting error, or the change over time.
[0073]
Step d5: If it is determined that the vehicle has fallen, the fuel pump is stopped, fuel injection and ignition are stopped, and the engine is stopped. At this time, it is desirable to gradually reduce the engine output as described above.
[0074]
FIG. 10 is a flowchart of still another embodiment of the present invention.
This embodiment further enhances the reliability of the vehicle body inclination determination other than the fall of the wheelie or the like in the embodiment of FIG. 4 described above. That is, in the embodiment of FIG. 4, when the vehicle body is turned upside down or turned over by 90 ° or more, it may not be determined that the vehicle has fallen. In the present embodiment, such an upside-down fall is reliably determined.
[0075]
More specifically, when the vehicle body falls down by 180 °, the output of the vertical Z-axis sensor becomes 1 g Cos (180 °) = − 1 g as shown in FIG. Show. On the other hand, the output of the horizontal Y-axis sensor is 1 gSin (180 °) = 0 g as shown in FIG.
[0076]
In the present embodiment, such an erroneous determination is prevented. When the inclination of ± 90 ° or more is detected by the Z-axis sensor, it is determined that the vehicle has fallen regardless of the Y-axis sensor.
[0077]
Step e1: The two-axis acceleration sensor is vertically arranged, and the detection directions are defined as a Z axis (vertical direction) and a Y axis (horizontal direction). The output voltage of the acceleration sensor is detected in the Z-axis and Y-axis directions.
[0078]
Step e2: It is determined from the detection output voltage of the Z-axis direction sensor whether or not it is upside down (fall over ± 90 °). That is, in the above-described cosine curve of FIG. 2A, the fall determination angle is set to ± 90 °, and it is determined whether or not the state is smaller than the corresponding output voltage value (g · cos (± 90 °)). If this state continues for 2 seconds or more, it is determined that the vehicle has fallen upside down. Note that, as described above, the requirement that the continuation lasts for 2 seconds or more is to increase the reliability of the fall judgment by voltage detection.
If it is determined that the vehicle has fallen upside down, the process immediately proceeds to step e4 to perform a fall control such as stopping the fuel pump.
[0079]
Step e3: If it is determined in step e2 that the sensor in the Z-axis direction is not an upside-down (not tilted by more than ± 90 °), the sensor further falls by the detection output voltages of the Z-axis sensor and the Y-axis direction sensor. (Falling within ± 90 °) is determined.
[0080]
That is, first, it is determined whether or not the vehicle has fallen according to the detection output voltage of the Z-axis direction sensor. As described above, it is determined whether or not the state is smaller than the output voltage value (g · cos (± 70 °)) corresponding to ± 70 °, which is the fall determination reference angle, in the cosine curve of FIG. . If this state continues for 2 seconds or more, it is determined that the vehicle has fallen. Note that, as described above, the requirement that the continuation lasts for 2 seconds or more is to increase the reliability of the fall judgment by voltage detection.
[0081]
Furthermore, in order to confirm that the fall determination by the Z-axis sensor is not a wheely or steep running, it is determined whether the Y-axis sensor is tilted, and it is determined that the Y-axis sensor has fallen only when the Y-axis sensor is also determined to be tilted. . In this case, the fall determination reference angle is set to ± 50 °. Thereby, as can be seen from the graph of FIG. 1 described above, the detection accuracy of the horizontal Y-axis sensor is higher than when the determination angle is ± 70 °.
[0082]
That is, in the Y-axis fall determination, in the sine curve of FIG. 1A described above, the fall determination reference angle is set to ± 50 °, and the corresponding output voltage value of the Y-axis sensor is (g · sin (50 °)). ) Is greater than or less than (g · sin (−50 °)). If this state continues for 2 seconds or more, it is determined that the vehicle has fallen.
[0083]
Even if the Z-axis sensor determines that the vehicle has fallen, if the Y-axis sensor detects that the vehicle is not tilted in the left-right direction, the vehicle body is tilted in the front-rear direction by a wheelie or the like. repeat.
[0084]
Step e4: If it is determined that the vehicle has fallen, the fuel pump is stopped, fuel injection and ignition are stopped, and the engine is stopped. At this time, it is desirable to gradually reduce the engine output as described above.
[0085]
FIG. 11 is a flowchart of still another embodiment of the present invention. FIG. 12 is a graph of tan (tangent) output data used in this embodiment.
[0086]
If an acceleration sensor is provided on a motorcycle, noise is included in the sensor output due to engine vibration, road surface irregularities, and the like. For this reason, if a logic that determines that the vehicle has fallen over a certain time with respect to a certain threshold value is set, it becomes larger or smaller than the threshold value due to vibration repeatedly, and at a set angle, It cannot be detected. In this case, for example, if a low-pass filter such as a CR filter is provided to eliminate the vibration component, the detection can be performed at the falling angle of the set threshold value. However, in this case, there is a problem that the response time is long and the detection time is long.
[0087]
Therefore, in the present embodiment, the tangent of the output of the vertical sensor and the output of the horizontal sensor is determined, and the fall is determined based on the tangent output. And the fluctuation of the horizontal sensor cancel each other out, so that the fall can be determined at the set detection angle.
[0088]
Step f1: The two-axis acceleration sensor is arranged vertically, and the detection directions are set to the Z axis (vertical direction) and the Y axis (horizontal direction). The output voltage of the acceleration sensor is detected in the Z-axis and Y-axis directions.
[0089]
Step f2: Based on the detection output voltage of the Z-axis direction sensor, it is determined whether or not it is upside down (fall over ± 90 °). That is, in the above-described cosine curve of FIG. 2A, the fall determination angle is set to ± 90 °, and it is determined whether or not the state is smaller than the corresponding output voltage value (g · cos (± 90 °)). If this state continues for 2 seconds or more, it is determined that the vehicle has fallen upside down. Note that, as described above, the requirement that the continuation lasts for 2 seconds or more is to increase the reliability of the fall judgment by voltage detection.
[0090]
If it is determined that the vehicle has fallen upside down, the process immediately proceeds to step f4 to perform a fall control such as stopping the fuel pump.
[0091]
Step f3: If it is determined in the above step f2 that the sensor in the Z-axis direction is not an upside-down (not tilted more than ± 90 °), the sensor is further turned over by the detection output voltages of the Z-axis sensor and the Y-axis direction sensor. (Falling within ± 90 °) is determined.
[0092]
That is, first, the output voltage of the horizontal Y-axis sensor shown in FIG. 1A and the output voltage of the vertical Z-axis sensor shown in FIG. 2A are detected, and the tangent (tan) = (Y-axis output) Voltage) ÷ (Z-axis output voltage) is obtained by calculation. It is determined whether the tan output value is smaller than 1 g · tan (−α) or larger than 1 g · tan α, where the fall angle is α. If any one of the conditions is continuously satisfied for 2 seconds or more, it is determined that the vehicle has fallen. The reason that it is required to last for 2 seconds or more is to increase the reliability of the fall judgment based on the tangent output value. If both are not satisfied, it is determined that the vehicle has not fallen.
[0093]
To explain with a graph, the tangent curve output obtained from the sine curve output from the horizontal Y-axis sensor shown in FIG. 1A and the cosine curve output from the vertical Z-axis sensor shown in FIG. Is represented. In FIG. 12, since it is determined in step f2 that the vehicle is not overturned, the vehicle body angle is in the range of −90 ° to + 90 °. Within this range, it is determined whether the left side (− side) or the right side (+ side) of the vehicle body has exceeded the overturning angle α.
[0094]
The overturning angle α is set in consideration of a vehicle type of a scooter type or a normal motorcycle type, a vehicle body size, a displacement, and the like. This α may be rewritable on a program according to a vehicle type or the like.
[0095]
In this way, by using the two-axis sensor including the vertical placement to determine the fall by the tangent of the output of both sensors, the noise is canceled out. Therefore, even if the sensor output fluctuates due to vibration, etc., the fall can be determined reliably. Can be.
[0096]
Step f4: If it is determined that the vehicle has fallen, the fuel pump is stopped, fuel injection and ignition are stopped, and the engine is stopped. At this time, it is desirable to gradually reduce the engine output as described above.
[0097]
Next, a description will be given of a mounting structure of the ECU incorporating the overturn sensor to a vehicle body.
FIG. 13 is an external view of a small motorcycle to which the present invention is applied.
[0098]
The vehicle body 1 has a handle 2 at a front portion, and the handle 2 is connected to a front wheel 5 via a steering shaft 4 through which a head pipe 3 is inserted. The body frame 6 is connected to the head pipe 3. The body frame 6 forms a frame structure of the entire body. The front part of the vehicle body is covered with a cowling 7. The vehicle body 1 is covered with a vehicle body cover 8 from outside the vehicle body frame 6. A seat 9 is provided at the center of the vehicle body, a fuel tank 10 is provided below the seat 9, and a helmet box (storage) 11 is provided behind the seat. The fuel tank 10 supplies fuel to an injector (not shown) via a fuel hose (not shown). One end of a breather hose 12 is connected to an upper part of the fuel tank 10, and the other end is connected to a canister 13. The canister 13 is connected to an intake system (for example, a throttle body) via a purge hose 14. A throttle wire 15 is attached to a throttle grip (or lever) of a right handle portion (not shown) and connected to a throttle valve of an intake system. Similarly, a brake cable 16 is attached to a brake lever (not shown) of a handle portion, and is connected to a brake camshaft 18 of a rear wheel 17.
[0099]
The engine unit 19 is mounted on the body frame 6 at the center of the body. The engine unit 19 includes an engine (not shown) and a speed reducer 24 integrally connected to a crankcase (not shown). The engine unit 19 is rotatably suspended around a pivot 22 with respect to a lower body frame member 21 constituting a part of the body frame 6 via an engine bracket 20. The rear wheel 17 is connected to the rear of the engine unit 19, and the lower end of the damper 23 is pivotally mounted. The upper end of the damper 23 is pivotally attached to a rear body frame (not shown) that forms a part of the body frame 6. As a result, the engine unit 19 can swing about the pivot 22 together with the rear wheel 17, and a swing unit type engine is formed.
[0100]
An air cleaner 25 is provided above the speed reducer 24. An outside air intake opening 25a is opened at the front of the air cleaner 25, and a dustproof cover 26 made of rubber or resin is provided inside the vehicle body cover 8 so as to cover this opening. 27 is a stand and 28 is a kick lever.
[0101]
FIGS. 14 and 15 are a side view and a plan view, respectively, showing a main part of a motorcycle including the fuel injection engine according to the present invention. FIG. 16 is an enlarged view of the intake system.
[0102]
An engine 29 is provided below the fuel tank 10. This engine 29 is a four-cycle single cylinder engine equipped with a fuel injection injector. A crankcase (not shown) of the engine 29 is integrally connected to a speed reducer 24 composed of, for example, a V-belt type stepless speed reduction mechanism, and constitutes an engine unit 19 of a swing unit engine type as a whole. A duct 30 is connected to a front portion of the speed reducer 24 and sucks outside air from an open end portion 30a of the duct 30 to supply the air into the speed reducer 5 to cool the inside. A rear output shaft (not shown) of the speed reducer 24 is connected to an axle of the rear wheel 17.
[0103]
An engine bracket 20 is integrally connected to a front portion of the swing unit engine type engine unit 19. A link plate 32 is pivotally attached to the engine bracket 20 via a shaft 31. The link plate 32 is rotatably attached to the lower vehicle body frame member 21 via the pivot 22.
[0104]
A damper (shock absorber) 23 is provided at the rear of the engine unit 19. The upper end 33 of the damper 23 is pivotally connected to a rear body frame member 34, and the lower end 35 is pivotally connected to a bracket 36 at the rear end of the engine unit 19. As a result, the engine unit 19 is swingably mounted on the body frame about the front pivot 22. As shown in FIG. 16, the cylinder 37 of the engine 29 is inclined forward almost to the level. The crankshaft 38 swings about the pivot 22 as shown by an arrow D together with the shaft 31 of the engine bracket 20 (FIG. 14).
[0105]
The intake side of the engine 29 is provided with an intake manifold 39 communicating with an intake port (not shown) of the cylinder head and an intake pipe 40 (FIGS. 15 and 16) connected thereto, and an exhaust pipe 41 (FIG. ) Is connected. The intake pipe 40 is a bent elbow-shaped intake pipe. As shown in FIG. 16, the flanges 43 butt against each other via a heat insulating material 42 made of resin, and are fixed by two bolts 44. 45 is a maintenance cover for the valve operating cam. The engine 29 is provided with a water temperature sensor 46 (FIGS. 15 and 16). The detection output signal of the water temperature sensor 46 is sent to the engine control unit 47 (FIG. 15) via the water temperature signal cable 89 (FIG. 15) and the wire harness 72. The engine control unit 47 is further connected to a detection signal cable (not shown) of an intake air temperature sensor and an intake pressure sensor described later via a wire harness 72, and controls opening and closing of a throttle valve (not shown) based on these detection data. I do.
[0106]
A throttle body 48 is connected to the intake manifold 39 via the aforementioned bent elbow-shaped intake pipe 40. The throttle body 48 is connected to the air cleaner 25 via a joint 49. The injector 50 is mounted on the intake pipe 40.
[0107]
A throttle valve (not shown) is mounted in the throttle body 48, and a diaphragm type suction piston 51 is mounted upstream thereof. As will be described later, the suction piston 51 has a diaphragm chamber 52 provided above the throttle body 48, and an air intake (atmosphere opening end) 54 of an atmosphere passage 53 for introducing atmosphere into the diaphragm chamber 52. It is provided below the body 48. A throttle wire 15 connected to a throttle lever or a throttle grip (not shown) via a link 55 is connected to the valve shaft of the throttle valve.
[0108]
The air intake opening 25a at the front of the air cleaner 25 is covered with a dustproof cover 26 (a dashed line in FIG. 13) made of rubber, resin, or the like. A vehicle body cover is further attached outside the dustproof cover 26. The air intake 54 of the suction piston 51 opens inside the dustproof cover 26.
[0109]
A heater type auto choke 56 and a suction pressure sensor 57 are provided on the throttle body 48 adjacent to the suction piston 51 (FIG. 15). The auto choke 56 opens and closes a bypass pipe (not shown) that connects the upstream side and the downstream side of the throttle valve. The intake pressure sensor 57 communicates with the intake manifold 39 or the intake pipe 40 via a negative pressure hose 58 (FIG. 16). An air temperature sensor 59 (FIG. 15) is provided in the air cleaner 25.
[0110]
Note that the intake pressure sensor 57 may be provided near the intake manifold. Further, a throttle position sensor (not shown) may be provided on the valve shaft of the throttle valve opposite to the link 55. In this case, the auto choke 56 is provided upstream of the throttle valve so as not to interfere with the throttle position sensor.
[0111]
The lower front portion of the fuel tank 10 is fixed to left and right vehicle body frame members 61 via a bracket 60. A fuel hose 62 is pulled out from the rear of the fuel tank 10 to supply fuel to the injector 50. The fuel hose 62 is fixed to the rear body frame member 34 via a stay 63 (FIGS. 14 and 16). 64 (FIG. 14) is an overflow pipe. 65 (FIG. 15) indicates a battery, and 66 (FIG. 15) indicates a recovery tank for cooling water. As shown in FIG. 15, a secondary air introduction system 86 for purifying exhaust gas is provided on the right side of the center of the vehicle body. The secondary air introduction system 86 communicates with an intake manifold via a negative pressure hose 87, and supplies outside air to a catalyst (not shown) via an air hose 88 according to the intake negative pressure to reburn the exhaust gas.
[0112]
A blow-by gas hose 90 is connected to the air cleaner 25, as shown in FIG. The blow-by gas hose 90 communicates with a cam chain chamber (not shown) that communicates with a crankcase (not shown) of the engine 29 to prevent oil seals from dropping off and loss horsepower due to a rise in pressure in the engine crankcase or the like. The blow-by gas hose 90 is connected to the clean side after passing through the element in the air cleaner, and the blow-by gas is introduced again into the combustion chamber.
[0113]
The fuel tank 10 communicates with the canister 13 via the breather hose 12 as shown in FIG. A rollover valve 124 is provided in the breather hose 12. The rollover valve 124 is closed when the vehicle falls down to prevent fuel from flowing out of the fuel tank 10.
[0114]
FIGS. 17A and 17B are a front side front view and a left side view of a mounting portion of the engine control unit, respectively.
In this arrangement example, the engine control unit (ECU) 47 has a substantially rectangular body shape in which the thickness of a lower portion 47b protruding to the front side is larger than the upper portion 47a and has a step, and the rear surface side forms a rectangular flat mounting surface 47c. Ear pieces 158 are provided on the left and right sides of the same surface as the mounting surface 47c. Each ear piece 158 is fixed to a stay 160 welded and fixed to the inner surface side of the fuel tank supporting bracket 60 by a bolt 159. A wire harness 72 is connected to a lower portion of the ECU 47 via a coupler 161.
[0115]
The bracket 60 is joined to a body frame member 61 joined to the right and left rear body frame members 34. The left and right rear body frame members 34 are joined to the front body frame member 140 via the elbow frames 145, respectively. The lower vehicle body frame member 21 is joined to the elbow frame 145, and a pivot 22 for swingably supporting the engine unit 19 (FIGS. 13 and 14) is provided on the lower vehicle body frame member 21. Reference numeral 162 denotes a tandem rider's foot pipe frame, and reference numeral 163 denotes a side stand.
[0116]
The fuel tank (not shown) is supported and disposed on a support member (not shown) provided between the upper portions of the left and right brackets 60 and a stay 63 provided on the upper portion of the rear body frame member 34.
[0117]
A circuit board (not shown) arranged parallel to the mounting surface 47c is accommodated in the ECU 47, and a two-dimensional (two-axis) acceleration sensor (not shown) has a detection surface parallel to the board plane on the circuit board. Has been implemented. Therefore, the overturning sensor including the two-dimensional acceleration sensor is attached to a position protected by the left and right brackets 60 at substantially the center in the lateral direction of the vehicle body with its detection surface substantially perpendicular to the longitudinal direction of the vehicle body.
[0118]
FIGS. 18A and 18B are a rear side front view and a left side view, respectively, of an ECU mounting structure according to another embodiment of the present invention.
In this example, two upper pipe frames 165 and two lower pipe frames 166 are welded and fixed to the rear of a head pipe 164 constituting a front part of a vehicle body frame, and are surrounded by these four pipe frames 165 and 166. This is a structure in which the ECU 47 is mounted at a position. The ear piece 158 of the ECU 47 is fixed to the bracket 167 with a bolt 159 with the mounting surface 47c facing the front. The bracket 167 has lower portions of the forked portions fixed to left and right lower pipe frames 166 with bolts 168, respectively. The bracket 167 may be fixed to the lower pipe frame 166 at appropriate places such as both side edges by welding.
[0119]
Reference numeral 169 denotes an electromagnetic pump for supplying fuel. 170 is a filter provided in the middle of a fuel hose (not shown) between the electromagnetic pump 169 and a fuel tank (not shown).
[0120]
Also in this embodiment, the ECU 47 sets the mounting surface 47c, which is parallel to the detection surface of a fall sensor (not shown) including an internal two-dimensional acceleration sensor, substantially perpendicularly to the front-rear direction of the vehicle body, and substantially right and left At the positions protected by the pipe frames 165 and 166.
[0121]
【The invention's effect】
As described above, according to the present invention, the acceleration sensor is used as a fall sensor, which is incorporated in the ECU to form an integrated unit, thereby improving the fall detection accuracy and simplifying the configuration. Can be efficiently laid out in a narrow space without restricting the layout. At the same time, the acceleration sensor is arranged vertically, that is, the acceleration detection direction when the vehicle body is not tilted is set to be perpendicular to the ground, so that the vehicle falls over or over the bank angle. In this case, the change in the detection output with respect to the change in the inclination angle in the vicinity of the bank angle (65 to 70 °), which is the discrimination angle of the overturning state, is large. Therefore, the change in the angle within a fixed A / D conversion output width is small. In addition, the conversion error can be reduced, and the accuracy of the fall determination can be improved and the reliability can be improved.
[0122]
In addition, a two-axis or three-axis acceleration sensor is used, and one axis is always set to the vertical detection direction (first detection direction), and the acceleration in the second detection direction in the vehicle width direction or the front-back direction is detected. Accordingly, when the angle of the first detection direction exceeds the falling angle, the inclination of the vehicle body due to wheely running or running on a slope is erroneously determined to be a fall based on the detection result in the second detection direction. Is prevented.
[0123]
Further, the acceleration in the first detection direction is detected based on a difference from a preset reference value in a non-tilted state, and the acceleration in the second detection direction is detected based on a change amount of the acceleration. According to the first detection direction, the inclination angle of the vehicle body is determined based on a difference from a reference value obtained by correcting an offset error of detection data based on an attachment error or the like, and an inclination other than a fall due to wheely running or the like is determined. For the second detection direction for discrimination, it is possible to discriminate between a fall and a wheelie by discriminating whether or not there is a change in inclination, so that it is not necessary to calculate a difference from the reference value, and therefore, the reference value is not required. Correction of the offset error is unnecessary.
[0124]
Further, according to the configuration in which the threshold value of the fall determination based on the first detection direction is changed based on the mounting angle of the acceleration sensor, the acceleration due to the mounting error of the ECU incorporating the acceleration sensor to the vehicle body or the like can be improved. When the sensor is mounted to be inclined with respect to the up-down direction of the vehicle body, the detection accuracy can be improved by changing the threshold value of the fall determination according to the angle of inclination.
[0125]
Further, a configuration is adopted in which the average detected value of the acceleration sensor when the amount of change in the detection output of the acceleration sensor is equal to or less than a certain value and the amount of change in the detection output of the acceleration sensor is equal to or less than a certain value is stored as a center value, and the center value is used as the reference value to determine a fall. According to the above, when the traveling speed is above a certain value and the output change of the acceleration sensor is below a certain value, it is determined that the vehicle is traveling in a straight posture with almost no inclination, and the average value of the sensor output at this time is a central value. Save as By detecting a change from the center value, it is possible to prevent a decrease in detection accuracy due to a variation in offset due to a temperature characteristic of the sensor or an installation error, or a change with time.
[0126]
Furthermore, according to the configuration in which a sensor for the vertical orientation and a sensor for the horizontal orientation are provided, and the fall is determined based on (horizontal sensor output) / (vertical sensor output), the fall detection is performed by vibration of the vehicle body or the like. Even if the output value fluctuates, a highly reliable fall detection without erroneous determination can be performed in a short time without using a noise removing filter or the like.
[0127]
Further, the tipping sensor comprises a two-dimensional acceleration sensor. The tipping sensor is housed in the ECU, and the ECU is mounted on the vehicle body frame so that the detection surface of the tipping sensor is substantially perpendicular to the vehicle longitudinal direction. According to the configuration described above, a two-dimensional (two-axis) acceleration sensor is used as a fall sensor incorporated in the ECU, and the two-dimensional detection surface is disposed substantially perpendicular to the vehicle front-rear direction, and the ECU is mounted on the vehicle body frame. , It is securely fixed to the vehicle body, and the reliability of mounting and detection is improved. In addition, the degree of freedom in mounting can be increased by, for example, mounting the ECU accommodating the tipping sensor on the vehicle body frame with a slight inclination in the front-rear direction corresponding to the surrounding component arrangement space, thereby facilitating component arrangement.
[0128]
Further, according to the configuration in which the ECU is provided at the center portion of the vehicle body in the left-right direction, the inclination fall in either the left or right direction can be similarly detected with high accuracy, and the reliability of the fall detection can be improved. It is mechanically protected by the left and right body frames to prevent damage during rollover.
[0129]
Further, a fuel tank mounting bracket is fixed to the vehicle body frame members disposed on the left and right of the vehicle body center portion, the ECU is disposed between these left and right brackets, and the ECU is fixed to each bracket via a stay. According to the configuration, the left and right brackets for mounting the fuel tank in the center of the vehicle body can be used to efficiently arrange the ECU between these brackets in a space-efficient manner, and various sensors such as a water temperature sensor around the engine and an intake air temperature sensor can be provided. The distance to the engine driving parts such as the sensor, the injector, the throttle valve, and the ignition coil is shortened, the wire harness including the signal cable and the like can be shortened, and the layout around the engine is simplified.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of an output voltage of a horizontally arranged acceleration sensor according to the present invention.
FIG. 2 is an explanatory diagram of an output voltage of a vertically arranged acceleration sensor according to the present invention.
FIG. 3 is a flowchart of a fall determination control by the uniaxial acceleration sensor of the present invention.
FIG. 4 is a flowchart of a fall determination control by the two-axis acceleration sensor of the present invention.
FIG. 5 is a block diagram of another embodiment of the present invention.
FIG. 6 is a flowchart of the operation of the embodiment of FIG. 5;
FIG. 7 is an explanatory diagram of an output voltage according to still another embodiment of the present invention.
FIG. 8 is a configuration explanatory view of still another embodiment of the present invention.
FIG. 9 is a flowchart of the operation of still another embodiment of the present invention.
FIG. 10 is a flowchart of the operation of still another embodiment of the present invention.
FIG. 11 is a flowchart of the operation of still another embodiment of the present invention.
FIG. 12 is a graph of the sensor output of the embodiment of FIG.
FIG. 13 is an external view of a small motorcycle according to the present invention.
14 is a side view of a main part of the motorcycle of FIG.
FIG. 15 is an essential part plan view of the motorcycle of FIG. 13;
16 is a configuration diagram of an engine portion of the motorcycle of FIG.
FIG. 17 is a configuration explanatory view of an ECU mounting structure according to the present invention.
FIG. 18 is a configuration explanatory view of an ECU mounting structure according to another embodiment of the present invention.
[Explanation of symbols]
1: body, 2: steering wheel, 3: head pipe, 4: steering shaft,
5: front wheel, 6: body frame, 7: cowling, 8: body cover,
9: Seat, 10: Fuel tank, 11: Helmet box,
12: breather hose, 13: canister, 14: purge hose,
15: throttle wire, 16: brake cable, 17: rear wheel,
18: brake camshaft, 19: engine unit,
20: engine bracket, 21: lower body frame member, 22: pivot,
23: damper, 24: reducer, 25: air cleaner 1,
25a: air intake opening, 26: dustproof cover, 27: stand,
28: kick lever, 29: engine, 30: duct, 30a: open end,
31: shaft, 32: link plate, 33: upper end, 33a: damper mounting hole,
34: rear body frame member, 35: lower end, 36: bracket,
37: cylinder, 38: crankshaft, 39: intake manifold, 40: intake pipe,
41: exhaust pipe, 42: heat insulating material, 43: flange, 44: bolt,
45: maintenance cover, 46: water temperature sensor, 47: engine control unit,
47a: upper part, 47b: lower part, 47c: mounting surface,
48: throttle body, 49: joint, 49a: joint end,
50: injector, 51: suction piston, 52: diaphragm chamber,
53: atmosphere passage, 54: atmosphere intake, 55: link, 56: auto choke,
57: intake pressure sensor, 58: negative pressure hose, 59: intake temperature sensor,
60: bracket, 61: body frame member, 62: fuel hose,
62a: fixed hose part, 62b: swing hose part, 63: stay,
64: overflow pipe, 65: battery,
66: recovery tank, 72: wire harness, 74: throttle valve,
86: secondary air introduction system, 87: negative pressure hose, 88: air hose,
89: water temperature signal cable, 90: blow-by gas hose,
101: acceleration sensor, 102: two-axis acceleration sensor, 103: filter,
104: A / D converter, 105: capacitor, 106: filter,
107: CPU, 108, 109: marking, 110: acceleration sensor,
111: printed circuit board, 124: rollover valve
140: Front body frame member, 145: Elbow frame,
158: ear piece, 159: bolt, 160: stay, 161: coupler,
162: Footrest pipe frame for tandem rider,
163: side stand, 164: head pipe,
165: Upper pipe frame, 166: Lower pipe frame,
167: bracket, 168: bolt, 169: electromagnetic pump,
170: Filter.

Claims (8)

Equipped with an ECU that controls the driving of the engine and a fall sensor that detects a fall based on the inclination angle of the vehicle body,
The fall sensor comprises an acceleration sensor,
In a motorcycle fall detection device incorporating the acceleration sensor in the ECU,
The acceleration sensor arranges a detection direction of the acceleration when the vehicle body is not tilted in a direction perpendicular to the ground, sets the detection direction as a first detection direction, and, together with the first detection direction, a second direction orthogonal to the first detection direction. A fall detection device for a motorcycle, which detects an acceleration in a detection direction of the motorcycle. The acceleration in the first detection direction is detected based on a difference from a preset reference value in a non-inclined state, and the acceleration in the second detection direction is detected based on a change in acceleration. The motorcycle fall detection device according to claim 1, wherein: The motorcycle fall detection device according to claim 1 or 2, wherein a threshold value of the fall determination based on the first detection direction is changed based on a mounting angle of the acceleration sensor. When the running speed is equal to or more than a certain value and the amount of change in the detection output of the acceleration sensor is equal to or less than a certain value, the detection value of the acceleration sensor is stored as data of a center value, and the center value is used as the reference value to determine a fall. 4. The motorcycle fall detection device according to claim 2. 5. The method according to claim 1, further comprising a sensor in a vertical direction and a sensor in a horizontal direction, and determining a fall based on (horizontal sensor output) / (vertical sensor output). Motorcycle fall detection device. The tipping sensor comprises a two-dimensional acceleration sensor, the tipping sensor is housed in the ECU, and the ECU is mounted on the body frame such that the detection surface of the tipping sensor is substantially perpendicular to the vehicle longitudinal direction. The motorcycle fall detection device according to any one of claims 1 to 5, characterized in that: The motorcycle fall detection device according to any one of claims 1 to 6, wherein the ECU is provided at a central portion of the vehicle body in the left-right direction. The fuel tank mounting brackets are fixed to the vehicle body frame members disposed on the left and right of the central portion of the vehicle, the ECU is disposed between these left and right brackets, and the ECU is fixed to each bracket via a stay. The motorcycle fall detection device according to any one of claims 1 to 7, wherein:

Images