JP4442889B2 - Saddle riding vehicle - Google Patents

Description

  The present invention relates to a straddle-type vehicle such as a motorcycle, and more particularly to control of a combustion state of an engine.

In the control of the combustion state of the engine, the control is generally performed with the goal of rotating the engine as stably and smoothly as possible. Conventionally, for example, in the engine idling operation region, the fuel injection amount is controlled so that the engine rotational speed becomes the target idle rotational speed, and the target idle rotational speed is finely set as the engine warms up. There is an example as described above (see, for example, Patent Document 1).
JP 2002-364433 A

  In the above-described conventional device, it is possible to make the engine rotation particularly stable and smooth during idling. However, because the engine rotation has become so stable and smooth, especially in vehicles such as motorcycles wearing helmets, the engine start switch is misunderstood that the engine has stopped despite idling rotation. There is a risk that the rider will perform an erroneous operation such as pressing. In particular, at urban intersections, there is a high concern about such erroneous operations due to exhaust sounds of other vehicles.

  The present invention has been made in view of the above-described conventional situation, and it is an object of the present invention to provide a straddle-type vehicle capable of notifying the rider that the vehicle is idling and avoiding an erroneous operation of the rider. .

The invention of claim 1 includes a vehicle body frame, an engine mounted on the vehicle body frame, an operation state detection unit that detects an operation state of the engine, and a combustion control device that controls the combustion state of the engine. a straddle-type vehicle, the combustion control apparatus, when the operating state of the engine detected by the operating condition detecting portion is a stable idling state, the Rukoto to change the combustion state of the engine, the engine or The sound pressure level or vibration level of the audible sound wave generated from the vehicle body frame is automatically changed, and the combustion state is not changed when the detected engine operating state is an unstable idling state .

  Here, in the present invention, the sound pressure level or the vibration level is automatically changed. For example, the peak value of the sound pressure level or the vibration level generated during one cycle of the engine (combustion once) It means that it changes every cycle, every plural cycles, or every random cycle. In this case, not only the case where the peak value of the sound pressure level or vibration level changes in comparison with the same cylinder, but also the case where the sound pressure level or vibration level changes between different cylinders is included. In the operating range where the engine combustion state is not changed, the combustion state of the engine is controlled to rotate the engine as stably and smoothly as possible, and is controlled by the same engine setting as in the conventional case.

  In the present invention, the audible sound wave means a sound having a frequency that is easily perceivable by humans. Specifically, for example, a sound of 20 Hz to 20 KHz is included in the audible sound wave referred to in the present invention.

  Further, in the present invention, it is not always necessary to change the combustion state of the engine in the idling state, and the combustion state is stabilized when the engine rotation is extremely unstable even during idling. Also good.

  The invention of claim 2 is characterized in that, in claim 1, the combustion control device automatically changes the sound pressure level of the audible sound wave and the sound wave in a high frequency range.

  Here, in the present invention, the sound wave in the high frequency range is a sound wave in the frequency range that is more easily sensed by humans among the above-mentioned audible sound waves. Included in the acoustic wave of the area.

  According to a third aspect of the present invention, in the first aspect, the combustion control device automatically changes the sound pressure level so as to be equal to or lower than a maximum sound pressure level of the audible sound wave and a low frequency sound wave. It is characterized by that.

  Here, in the present invention, the sound wave in the low frequency range is a sound wave that is relatively difficult for humans to sense among the above-mentioned audible sound waves. Included in sound waves.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the combustion control device changes the combustion state of the engine by changing the fuel supply amount without stopping the fuel supply to the engine. It is characterized by.

  According to a fifth aspect of the present invention, in any one of the first to third aspects, the combustion control device changes the combustion state of the engine by retarding or advancing the ignition timing of the engine.

  According to a sixth aspect of the present invention, in any one of the first to fourth aspects, the combustion control device intermittently changes the sound pressure level or vibration level of the audible sound wave by intermittently changing the combustion state of the engine. It is characterized by changing.

  A seventh aspect of the present invention is that, in any one of the first to fourth aspects, the control device randomly changes the sound pressure level or vibration level of the audible sound wave by randomly changing the combustion state of the engine. It is characterized by.

According to the invention of claim 1, when the engine is in a stable idling state, the combustion state changes, and therefore the sound pressure level or vibration level changes every cycle, every multiple cycles, or every random cycle. Compared to the case where the sound pressure level does not change, it is easier for the driver to feel that the engine is rotating. Can be prevented.

According to the invention of claim 2, since the sound pressure level of the audible sound wave and the sound wave in the high frequency range is automatically changed, the driver can feel the change of the sound pressure level more reliably. According to the invention of claim 3, the sound pressure level is automatically changed so that the sound pressure level is lower than the maximum sound pressure level of an audible sound wave and a low frequency sound wave. As described above, the above-described erroneous operation can be prevented without increasing the overall sound pressure level, that is, without causing problems such as exceeding the noise regulation.

According to the invention of claim 4, since the combustion state of the engine is changed by changing the fuel supply amount without stopping the fuel supply to the engine, the combustion state can be changed stably and easily. According to the invention of claim 5, the combustion state of the engine is changed by retarding or advancing the ignition timing of the engine. Therefore, the combustion state can be changed stably and easily, and the sound pressure level can be changed easily and reliably. According to the invention of claim 6, the combustion state of the engine is changed intermittently. The sound pressure level or vibration level of the audible sound wave is intermittently changed, and according to the invention of claim 7, the combustion state of the engine is changed randomly. Serial since as randomly changing sound pressure level or vibration level of audible sound waves, without increasing the overall sound pressure level, can be prevented an erroneous operation described above.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  1 to 11 are diagrams for explaining an embodiment of the present invention, FIG. 1 is a schematic configuration diagram thereof, FIG. 2 is a diagram showing a combustion control region, and FIGS. 3 to 8 are combustion control and sound pressure. FIG. 9 to FIG. 11 are diagrams illustrating the relationship between combustion control and exhaust gas components.

  In the figure, reference numeral 1 denotes a V-type two-cylinder engine for a motorcycle, in which a first cylinder 3 and a first cylinder head 5 are disposed at a front portion of an upper wall of the crankcase 2, and a second cylinder 4 and a second cylinder head 6 are disposed at a rear portion. Are arranged so as to form a V shape as a whole. The first and second pistons 7 and 8 are slidably inserted into the first and second cylinders (cylinder bores) 3a and 4a of the first cylinder 3 and the second cylinder 4, respectively. , 10 are connected to a common crankpin 11a of the crankshaft 11.

  The intake port 5a and the exhaust port 5b, which are formed to open to the combustion chamber of the first cylinder head 5, are opened and closed by the intake valve 12a and the exhaust valve 12b. The combustion chamber side openings of the intake port 6a and the exhaust port 6b are opened and closed by the intake valve 13a and the exhaust valve 13b. The first and second cylinder heads 5 and 6 are screwed so that the first and second spark plugs 23 and 24 are exposed to the inside of the combustion chamber.

  An air cleaner 20 common to both cylinders is connected to upstream ends of the first and second intake passages 5c and 6c connected to the first and second intake ports 5a and 6a. Further, first and second fuel injection valves 14 and 15 are disposed in the middle of the first and second intake passages 5c and 6c, and fuel is injected into the combustion chamber via the intake valve opening by the fuel injection valves. It has come to be. Further, upstream and downstream of the first and second fuel injection valves 14 and 15, first and second throttle valves 16 and 17 are disposed. Although not shown, shaft ends of the throttle valves 16 and 17 are arranged. Is provided with a throttle sensor for detecting the opening degree. In addition, first and second air flow meters 18 and 19 for detecting the intake air amount are disposed upstream of the throttle valves. Of course, an air intake pressure sensor that detects the internal pressure in the air intake passage may be used instead of the air flow meter.

  The intake air amount signals a1 and a2 detected by the first and second air flow meters 18 and 19, the crank angle signal v detected by the crank angle sensor 21 and the throttle opening signal detected by the throttle opening sensor are respectively shown. Input to the ECU 22. The ECU 22 functions as an operation state detection unit that detects the operation state of the engine based on the intake air amount, the engine rotation speed, and the throttle opening, and based on the operation state (operation range) detected by the detection unit. It functions as a device that controls the combustion state of the engine 1. The ECU 22 outputs fuel injection signals A1 and A2 to the first and second fuel injection valves 14 and 15, and ignition signals B1 and B2 to an ignition system (not shown) of the first and second ignition plugs 23 and 24, respectively. .

  Although not shown, the engine 1 is positioned on the vehicle body frame with the crankshaft 11 facing in the vehicle width direction, the first cylinder 3 on the front side in the vehicle front-rear direction, and the second cylinder 4 on the rear side. To be mounted. As an in-vehicle structure of the engine 1, when the engine 1 is mounted in a directly connected state so as to be a strength member of a vehicle body frame, or mounted through an elastic member such as a rubber damper, the engine 1 has an elastic range of the rubber damper. In both cases, it is possible to swing relative to the body frame.

  In the former case where the engine 1 is directly connected to the vehicle body frame, it is considered that the driver feels that the sound or vibration generated by the engine is emitted not only from the engine itself but also through the vehicle body frame. On the other hand, in the latter case where the engine 1 is mounted on the body frame with an elastic member interposed, it is considered that the amount of sound and vibration emitted from the engine to the outside through the body frame is greatly reduced. Thus, even in the same engine, a difference occurs in the sound and vibration transmitted to the driver due to the mounting structure on the body frame.

  And the combustion control apparatus (ECU) 22 in this embodiment is comprised so that the combustion state of the said 1st, 2nd cylinder 3a, 4a can be controlled separately. Specifically, in both the first cylinder 3a and the second cylinder 4a, the combustion state is changed every cycle, every multiple cycles, or every random cycle by changing the fuel supply amount based on the operating state of the engine. Either the change mode for changing or the stable mode for stabilizing the combustion state by stabilizing the fuel supply amount can be selected.

  In the present embodiment, the combustion control device 22 is a part of the first and second cylinders 3a and 4a in a part of the operation region (change operation region) to be described later. By setting the combustion state of the cylinder 4a to the change mode and the fuel state of the first cylinder 3a to the stable mode at all times, the sound pressure level of the audible sound wave generated from the engine 1 or the vehicle body frame is automatically changed. It is configured.

  In addition, in the operating range (stable operating range) other than the change operating range, the combustion control device 22 is in a stable mode in which the combustion state of both the first and second cylinders 3a and 4a is stabilized, and the engine or vehicle body The sound pressure level of the audible sound wave generated from the frame is automatically stabilized.

  Here, the sound pressure level is automatically changed when the peak value of the sound pressure level generated during one cycle of the engine, that is, during one combustion (crank angle of 720 °), is changed every cycle of the engine. Or it means that it changes every several cycles or every random cycle.

  More specifically, in the stable operation range, the amount of fuel supplied from the first and second fuel injection valves 14 and 15 to the first and second cylinders 3a and 4a is constant. On the other hand, in the change operation range, the amount of fuel supplied from the first fuel injection valve 14 disposed on the front side to the first cylinder 3a is constant, and the second fuel injection valve disposed on the rear side. The amount of fuel supplied from the engine 15 to the second cylinder 4a is changed for each cycle of the engine (cycle for one explosion), for every multiple cycles, or for every random cycle, and the combustion state of the engine changes accordingly. The sound pressure level of the audible sound wave changes.

  Specifically, the fuel supply amount to the second cylinder 4a is alternately changed between a reference amount (100%) and a smaller amount, for example, 80%. In this example, the fuel supply amount is changed every cycle such as 100%, 80%, 100%, 80%, and so on. Of course, 100%, 80%, 80%, 100%, 80%, 80%, 100% ..., 100%, 100%, 80%, 100%, 100%, 80%, etc. Various changes can be adopted. The reference amount means, for example, a fuel injection amount that becomes a stoichiometric air-fuel ratio or an output air-fuel ratio slightly richer than that. In this case, the amount of fuel supplied to the first cylinder 3a from the first fuel injection valve 14 on the front side is controlled to be constant to the reference amount.

  There are various modes for changing the fuel injection amount in the change mode, for example, between a reference amount (100%) and a larger amount, such as 170%, 200%, etc. A form that changes every random cycle can be adopted.

  In contrast to the above, it is also possible to change the fuel supply amount to the first cylinder 3a while keeping the fuel supply amount to the second cylinder 4a constant.

  Moreover, various aspects can be considered also about the said change driving | operation area. For example, as shown in FIG. 2, during the first idling (S1) immediately after the cold start of the engine, the change mode is not adopted (off) and is stable from the engine temperature, the engine speed, the fuel injection instruction time, or the like. When it is determined that the idling state has been achieved (S2), the change mode is adopted (turned on). When the throttle is opened by idling (S3), the change mode is turned off. Further, when the transmission is set to the first speed (S4), the change mode is kept on, and when the vehicle starts with the throttle opened (S5), the change mode is turned off. Further, when the vehicle stops (vehicle speed zero) (S6), when the transmission is switched to neutral (S7), or when it returns to idling (S8), the change mode is turned on.

  In the idling operation range (S2), it is not always necessary to control to the constantly changing mode. Even in the idling operating range, for example, when the engine rotation becomes unstable, the engine combustion state is changed to the changing mode. The stable mode may be used instead.

  In a state in which the combustion state of the second cylinder 4a is in the change mode, the sound pressure level, that is, the peak value of the sound pressure in one cycle is every engine cycle, every multiple cycles, or every random cycle. Since it changes, it is easier for the rider to feel that the engine is rotating than when the sound pressure level does not change, and therefore it is possible to reliably tell the rider that the engine is moving. Further, since the sound pressure level changes in the change mode, it is possible to tell the rider that the engine is moving by a change in sound even when the rider is not in the vehicle.

  In addition, when idling, the second cylinder 4a is in the change mode and the rider is surely notified that the engine is moving due to the change in the sound pressure level, so that the rider can stop the engine even when the engine is idling. It is possible to avoid an erroneous operation such that the engine start switch is pushed by mistake.

  In addition, since it is set to change mode only when idling, it switches to stable mode after starting, so when changes in sound and vibration are burdened on the rider, such as during constant speed driving in touring etc., The sound pressure level is stabilized, and it is possible to avoid the problem that the rider gets tired due to changes in unnecessary sound and vibration.

  Further, in the acceleration traveling operation region such as start acceleration and overtaking acceleration, the engine combustion state is set to the stable mode, so that deterioration of acceleration can be suppressed. That is, when the change mode is realized by reducing the fuel supply amount every predetermined cycle, the engine output is reduced accordingly. Accordingly, when the change mode is adopted in the acceleration travel operation region, there is a problem that the acceleration performance is deteriorated. However, in this embodiment, such a problem does not occur because the acceleration travel operation region is in the stable mode.

  Furthermore, in the present embodiment, the combustion state of the second cylinder 4a is changed in the change operation range, but the combustion state of the first cylinder 3a is stabilized, so that the operation state of the entire engine is extremely low. It can avoid becoming unstable. This prevents the rider from misrecognizing that an abnormality has occurred in the engine.

  Note that the combustion state of each cylinder can be switched between a change mode and a stable mode by a manual changeover switch. In this case, the rider operates the engine according to the rider's preference. Only when you want to feel that, can you tell the engine movement.

Also, since the combustion state of the engine is switched to either the change mode or the stable mode by controlling the amount of fuel supplied to the engine, the combustion state can be changed stably and easily and reliably. The sound pressure level can be changed. Next, the results of experiments conducted to confirm the effect of the present invention will be described. In this experiment, a stable operation range (std) in which both the first cylinder 3a and the second cylinder 4a are in the stable mode, a change operation range in which the first cylinder 3a is in the stable mode, and the second cylinder 4a is in the change mode, The change of sound pressure level was compared. In the stable operation range (see FIG. 3), the fuel injection amount is constant for both the first and second cylinders 3a and 4a (100%), and in the change operation region, the reference amount is constant for the first cylinder 3a. For the second cylinder 4a, the fuel injection amount was changed for each cycle (see FIGS. 4 to 8).

  In the change operation range, the fuel supply amount to the second cylinder 4a is specifically 100% and 80% repeated (see FIG. 4A), and 100% and 170% repeated (FIG. 5). (See (a))), 100% and 200% repetition (see FIG. 6 (a) (reference), 100% and 120% repetition (see FIG. 7 (a)), 200, 180, 100, 80, Random including 60% (see FIG. 8A).

  The sound pressure level was measured at the outlet of the exhaust pipe, frequency components other than the frequency 5 KHz to 20 KHz were removed, and the sound pressure of the frequency 5 KHz to 20 KHz component was totaled.

  In the case of the stable operation range (std) (see FIG. 3B), the peak value of the sound pressure level is substantially constant between 85 and 86 dBF for both the first and second cylinders at the explosion timing. It can be seen that there is no change in the pressure level.

  On the other hand, in the change operation range, the sound pressure level at the explosion timing of the first cylinder does not change much, but the sound pressure level at the explosion timing of the second cylinder greatly changes. Specifically, in the case of 100-80% (FIG. 4), 100-170% (FIG. 5), and 100-200% (FIG. 6), 86 to 87 dBF and 89 to 90 dBF are generally set for each cycle. Has changed between. Further, when the fuel injection amount is changed randomly (FIG. 8), it changes between 85 dBF, 87 dBF, and 90 dBF. Further, the change in the sound pressure level in the case of 100 to 120% (FIG. 7) is larger than that in the stable operation region, although it is smaller than in the other change operation regions.

  From the above experimental results, the fuel supply amount of either the first cylinder or the second cylinder is made constant, and the fuel supply amount of the other cylinder is changed every cycle or randomly, so that the combustion of the entire engine It can be seen that the sound pressure level changes greatly without making the sound extremely unstable.

9 to 11 show measurement results of exhaust gas components (CO, HC, CO ₂ ) in the stable operation range and the change operation range. In this exhaust gas measurement, the fuel supply amount to the second cylinder is constant, and the fuel supply amount to the first cylinder is 100-80%, 100-170%, 100-200% for each cycle, It was changed to 60-150%, and random including 200, 180, 100, 80, 60%. In FIGS. 9 to 11, “with AI” and “AI cut” indicate when secondary air is supplied in the middle of the exhaust pipe and when it is not supplied.

  Regarding the CO of the exhaust gas component, when the fuel supply amount to the first cylinder is 100-170%, 100-200%, 60-150%, the CO of the first cylinder (change mode) is the second. It increases from the CO of the cylinder, 100-80%, and in the random case, the CO of the first cylinder is less than the CO of the second cylinder.

As for HC, although it hardly changes in the case of 100-80%, in other cases, the HC of the first cylinder is larger than that of the second cylinder. Furthermore in the case of CO ₂ is almost no change in the case of 100-80%, in other cases it can be seen that CO ₂ of the first cylinder is slightly lower than CO ₂ of the second cylinder.

  In order to change the sound pressure level without deteriorating the exhaust gas component in view of the above sound pressure level and exhaust gas component measurement results, the fuel supply amount must be set between a reference amount and a smaller amount. It is thought that it is desirable to change it (for example, 100-80%).

  Here, in the above embodiment, the case of a V-type two-cylinder engine has been described. However, the present invention can also be applied to a case of a multi-cylinder engine having three or more cylinders. In this case, some of the three or more cylinders are set to the change mode described above, and the remaining cylinders are set to the stable mode. As the number of cylinders in the change mode increases, the change in the sound pressure level and the like increases.

  In the above embodiment, the case of a plurality of cylinders has been described. However, the present invention can be applied to any engine having at least one cylinder, and thus can be applied to a single cylinder engine. By changing the combustion state of the specific cylinder of the engine within a range where no misfire occurs, the sound pressure level or vibration level of the audible sound wave generated from the engine or the vehicle body frame is automatically changed.

  In this case, even with a single cylinder, the combustion state is changed within a range where misfire does not occur.Therefore, the engine rotation does not become extremely unstable. Misrecognition can be avoided.

  In the above embodiment, the combustion state is changed by changing the fuel supply amount, and the sound pressure level is changed. However, other than the above, for example, the ignition timing is changed every cycle, every multiple cycles, or every random cycle. It is also possible to change the combustion state by advancing or retarding, thereby changing the sound pressure level of the audible sound wave.

  Moreover, although the case where the sound pressure level of an audible sound wave was changed was demonstrated in the said embodiment, you may make it change the vibration level generate | occur | produced from an engine or a vehicle body frame by changing a combustion state similarly to the above.

It is a combustion control block block diagram of the engine of one Embodiment of this invention. It is a figure which shows the combustion control area | region of the said embodiment. It is a figure which shows the experimental result of the said embodiment. It is a figure which shows the experimental result of the said embodiment. It is a figure which shows the experimental result of the said embodiment. It is a figure which shows the experimental result of the said embodiment. It is a figure which shows the experimental result of the said embodiment. It is a figure which shows the experimental result of the said embodiment. It is a figure which shows the experimental result of the said embodiment. It is a figure which shows the experimental result of the said embodiment. It is a figure which shows the experimental result of the said embodiment.

Explanation of symbols

1 engine 22 ECU (operation state detection unit, combustion control device)

Claims (7)

A straddle-type vehicle comprising: a vehicle body frame; an engine mounted on the vehicle body frame; an operation state detection unit that detects an operation state of the engine; and a combustion control device that controls a combustion state of the engine. the combustion control device, audible sound waves when the operating state of the engine detected by the operating condition detecting portion is a stable idling state, where the Rukoto changing the combustion state of the engine, generated from the engine or the vehicle body frame A straddle-type vehicle that automatically changes the sound pressure level or vibration level of the engine and does not change the combustion state when the detected engine operating state is an unstable idling state . 2. The straddle-type vehicle according to claim 1, wherein the combustion control device automatically changes a sound pressure level of the audible sound wave and a high-frequency sound wave. 2. The power generation method according to claim 1, wherein the combustion control device automatically changes the sound pressure level so as to be equal to or lower than a maximum sound pressure level of the audible sound wave and a sound wave in a low frequency range. Type vehicle. 4. The straddle type according to claim 1, wherein the combustion control device changes the combustion state of the engine by changing the fuel supply amount without stopping the fuel supply to the engine. vehicle. 4. The straddle-type vehicle according to claim 1, wherein the combustion control device changes the combustion state of the engine by retarding or advancing the ignition timing of the engine. 5. The combustion control apparatus according to claim 1, wherein the combustion control device intermittently changes a sound pressure level or a vibration level of the audible sound wave by intermittently changing a combustion state of the engine. Saddle type vehicle. 5. The saddle type according to claim 1, wherein the control device randomly changes a sound pressure level or a vibration level of the audible sound wave by randomly changing a combustion state of the engine. vehicle.

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