JP4636327B2 - Evaporative fuel treatment system for outboard motor - Google Patents

Description

  The present invention relates to an evaporative fuel treatment apparatus for an outboard motor having a canister for adsorbing evaporative fuel generated in a vapor separator.

  Vaporized fuel is generated in a vapor separator provided in an outboard motor having an electronic fuel injection system. Conventionally, in such an outboard motor, the evaporated fuel generated in the vapor separator is discharged out of the outboard motor cover, in the drive shaft housing, in the engine, and the like. If discharged outside the outboard motor cover, there is a harmful effect of air pollution, and if discharged into the drive shaft housing, backfire may occur. Also, the engine cannot be discharged when the engine is stopped.

  Therefore, in Patent Document 1 below, a vapor separator with a built-in canister is provided in the outboard motor, and the evaporated fuel is processed by the canister.

By the way, some four-wheeled vehicles have an evaporative fuel processing device including a canister for processing evaporative fuel in the engine room outside the fuel tank (Patent Document 2 below).
Japanese Patent Laid-Open No. 2002-161813 JP 2003-328865 A

  However, in an outboard motor, the outboard motor body may be tilted up / down, and the posture may be changed greatly. Furthermore, if the hull itself changes its attitude even during sudden acceleration / deceleration, hump, planing, rough sea navigation, etc., the outboard motor body also changes its attitude in conjunction with the hull against the horizontal state. .

  In this way, when the attitude of the outboard motor body largely fluctuates with respect to the horizontal state or the oil level fluctuates up and down, liquid fuel or a large amount of evaporated fuel in the vapor separator flows into the canister. There is a problem that the function of the canister may be lowered.

  The present invention has been made to solve the above-described problems of the prior art, and an object of the present invention is to provide an evaporative fuel processing apparatus for an outboard motor that can prevent the function of the canister from deteriorating due to the inflow of liquid fuel from the vapor separator. Is to provide.

In order to achieve the above object, an evaporative fuel treatment apparatus for an outboard motor according to claim 1 of the present invention introduces evaporative fuel in a vapor separator, adsorbs the introduced evaporative fuel, an intake device, and the canister A purge valve for controlling the discharge of the evaporated fuel adsorbed by the canister to the intake device, an air vent valve for controlling the introduction of outside air to the canister, and the vapor separator A canister protection valve provided between the vapor separator and the canister for preventing liquid fuel from flowing into the canister, and a control means for controlling opening and closing of the purge valve, the air vent valve and the canister protection valve. The purge valve, the air vent valve and the canister protection valve are all closed when the main switch is turned off. It is an electromagnetic valve, wherein the control unit, the main switch is also turned off, the canister protection valve, characterized in that closing control after maintained only in the open state engine stop after a predetermined time.

According to the first aspect of the present invention, it is possible to prevent the function of the canister from being deteriorated due to the inflow of liquid fuel from the vapor separator. In addition, it is possible to ensure the processing of the evaporated fuel generated in the vapor separator after the engine is stopped.

According to the second and third aspects, while the evaporated fuel generated in the vapor separator during the operation of the engine is being processed, the inflow of the liquid fuel from the vapor separator to the canister due to the attitude change of the outboard motor can be prevented. Functional deterioration can be prevented.

According to the fourth aspect of the present invention , the actual inclination angle of the outboard motor is accurately detected and the canister protection valve is controlled to be closed, so that the inflow of liquid fuel from the vapor separator to the canister due to the attitude change of the outboard motor It can prevent more appropriately.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a right side view of an outboard motor to which an evaporated fuel processing apparatus according to an embodiment of the present invention is applied. The figure shows a state in which the main body 1A of the outboard motor 1 is tilted down and substantially upright. Hereinafter, with respect to the outboard motor 1, the right side (the hull side) of the figure is referred to as "front", the left side as "rear", and the upper side as "upward".

  As shown in FIG. 1, the outboard motor 1 includes an engine holder 3, and the engine 2 is installed above the engine holder 3. The engine 2 is a water-cooled four-cycle in-line four-cylinder engine in which a crankshaft (not shown) is disposed substantially vertically (in a vertical position).

  An oil pan 4 is joined and fixed to the lower surface of the engine holder 3, and a drive shaft housing 9 and a gear case 10 are sequentially arranged below the oil pan 4. The engine cover 5 surrounds the engine 2, the engine holder 3, and the oil pan 4. Covered.

  A drive shaft (not shown) is arranged substantially vertically in the engine holder 3, the oil pan 4 and the drive shaft housing 9, and the drive shaft receives a rotational force from the crankshaft to bevel gears and propeller shafts in the gear case 10. Is also configured to drive the propeller 6 that is a propulsion device.

  A clamp bracket bracket 28 is fixed to the main body 1A of the outboard motor 1 via a mounting bracket (not shown), and the outboard motor 1 is connected to the hull 70 (see FIG. 3) via the clamp bracket 28. It is fixed to the stern board 80.

  The clamp bracket 28 is provided with a swivel bracket 36 via a tilt shaft 35, and a pilot shaft 37 is pivotally supported in the swivel bracket 36 in a vertical direction so as to be rotatable. The main body 1A of the outboard motor 1 can be steered left and right around the pilot shaft 37 with respect to the clamp bracket 28, and can be tilted up around the tilt shaft 35.

  A water pump 27 driven by the drive shaft is installed on the upper part of the gear case 10. The gear case 10 is provided with a water inlet 8, and external water (seawater, lake water, river water, etc.) is taken in as cooling water from the water inlet 8 by the water pump 27. The cooling water cools each part of the engine 2, and the water that has returned after performing the cooling function is discharged into the water outside the outboard motor 1 from the center hole (not shown) of the propeller 6 together with the exhaust gas.

  2A and 2B are side views of the outboard motor angle detection device provided between the clamp bracket 28 and the swivel bracket 36 and the peripheral portion thereof. FIG. 2A shows a tilt-down state of the main body 1A of the outboard motor 1, and FIG. 2B shows a state during the tilt-up of the main body 1A.

  The outboard motor angle detection device 83 detects a relative inclination angle of the main body 1A of the outboard motor 1 with respect to the stern plate 80 of the hull 70, in particular, an inclination angle in the front-rear direction. The outboard motor angle detection device 83 mainly includes a rotation detection element 84 such as a variable resistor or a hall element provided on the clamp bracket 28 fixed to the stern plate 80, and the rotation detection element 84. The lever 81 is pivotally provided at the center, and a convex portion 82 is provided on the movable swivel bracket 36. The free end of the lever 81 is always on the convex portion 82 side by a spring (not shown). It is biased and abuts against the convex portion 82.

  Then, when the main body 1A is tilted up, for example, when the swivel bracket 36 is tilted upward (clockwise in FIG. 2A) via the tilt shaft 35, the convex portion 82 is moved along with this tilting, The lever 81 rotates clockwise about the rotation detection element 84 (see FIG. 2B). Then, the rotation amount of the swivel bracket 36 relative to the clamp bracket 28 is output from the rotation detection element 84 as an inclination angle signal θMOT indicating the inclination angle of the main body 1A relative to the stern plate 80.

  Assuming that the direction in which the main body 1A tilts up is “+” and the inclination angle when the main body 1A is in the vertical state is ± 0 °, the outboard motor angle detection device 83 has a rotation area including a trim area and a tilt area. The angle of the main body 1A can be detected linearly from the minimum trim angle (for example, −10 °) to the maximum tilt angle (for example, + 60 °).

  FIG. 3A is a side view showing the configuration of the hull angle detection device that detects the inclination angle of the hull 70. FIGS. 3B and 3C are operation diagrams of the hull angle detection device. The hull angle detection device 90 detects the inclination angle of the hull 70 in the front-rear direction, and is fixedly provided on the stern plate 80 near the outboard motor 1.

  In the hull angle detection device 90, a first outer pole 98 and a second outer pole 99, which are negative terminals, are provided inside each of the extending portions 90a and 90b of the U-shaped cover 100. Conductors 96 and 97 are provided above the outer poles 98 and 99 with insulators 94 and 95 interposed therebetween. On the other hand, a pendulum 91 made of a conductive member is provided in the cover 100, and a ball portion 92 is provided at the upper end of the pendulum 91, and a contact portion 93 that functions as a + terminal is provided at the lower end. The ball portion 92 of the pendulum 91 is loosely fitted in a space formed by the upper ends of the conductors 96 and 97 and the semicircular portion of the cover 100. The ball portion 92 of the pendulum 91 is held in contact with the inner upper ends of the conductors 96 and 97, the contact portion 93 is freely swingable, and the pendulum 91 always maintains a posture perpendicular to the vertical direction. It is like that.

  The hull angle detection device 90 is supplied with electric power from the outboard motor 1. For example, the cover 100 is fixed to the stern plate 80 on the extended portion 90a side and swings together with the hull 70 (and the stern plate 80). When the hull 70 is horizontal, the contact portion 93 is located in the middle of the extending portions 90a and 90b and is separated from the extending portions 90a and 90b, as shown in FIG.

  When the bow is lowered by more than a predetermined value during rough wave navigation or the like, as shown in FIG. 5B, the cover 100 is tilted clockwise and the contact portion 93 comes into contact with the extended portion 90b. Then, the conductor 97 and the second outer pole 99 are electrically connected via the pendulum 91, and θB (−) indicating a minus inclination is output as the detection signal θB. On the other hand, when the bow is lifted by a predetermined amount or more during humping or rough sea navigation, the cover 100 is tilted counterclockwise and the contact portion 93 comes into contact with the extending portion 90a as shown in FIG. Then, the conductor 96 and the first outer pole 98 are electrically connected via the pendulum 91, and θB (+) indicating a positive inclination is output as the detection signal θB. The inclination angle of the hull 70 indicated by the detection signal θB is, for example, that θB (−) is “−10 °” and θB (+) is “+ 10 °”.

Both the inclination angle signal θMOT from the outboard motor angle detection device 83 and the detection signal θB from the hull angle detection device 90 are supplied to an ECU (engine control unit) 63 described later (see FIG. 6). The ECU 63 calculates an inclination angle φ with respect to the horizontal state (horizontal line) of the main body 1A of the outboard motor 1 by the following formula 1. The inclination angle φ is an angle that takes into account the inclination of the hull 70 as well as the angle of the main body 1A alone. The ECU 63 controls opening and closing of a canister protection valve 72 described later based on the calculated inclination angle φ.
[Formula 1] φ = θMOT + θB
FIG. 4 is a right side view of the engine portion of the outboard motor 1. FIG. 5 is a plan view showing the inside of the front half of the outboard motor 1.

  As shown in FIG. 4, a low-pressure fuel filter 19 and a low-pressure fuel pump 20 connected to the low-pressure fuel filter 19 are disposed at the rear of the engine 2, and a delivery pipe 21 is disposed in the vertical direction. The

  As shown in FIGS. 4 and 5, an intake manifold 31 is provided on the right side of the engine 2. As shown in FIG. 4, the intake manifold 31 includes a surge tank 32 at the front thereof and four intake branch pipes 33 (33 (1) to 33 (4)). The intake branch pipes 33 (1) to 33 (4) are arranged in parallel in the vertical direction corresponding to each cylinder (not shown), and communicate the surge tank 32 and the corresponding intake port. Each intake port is provided with an injector 25 (25 (1) to 25 (4)). A throttle body 56 communicates with the intake manifold 31, and these constitute an intake device.

  As shown in FIGS. 4 and 5, a vapor separator 24 is disposed in front of the surge tank 32 at the front right side of the engine 2. A high pressure fuel filter 18 is disposed above the vapor separator 24. The vapor separator 24 includes a vapor separator tank, a pressure regulator, and a high-pressure fuel pump (all not shown). The vapor separator 24 is connected to the low-pressure fuel pump 20 by a fuel hose 40, and a delivery pipe through the high-pressure fuel filter 18. 21 is connected.

  As shown in FIG. 4, a portable fuel tank 38 is disposed on the hull 70. A fuel hose 23 is disposed at the lower right side of the engine 2. A fuel hose (not shown) from the fuel tank 38 is connected to the entrance 45 at the front end of the fuel hose 23.

  As shown in FIGS. 4 and 5, a canister 51 is disposed in the vicinity of the upper portion of the surge tank 32 on the right side of the front portion of the engine 2. The canister 51 is located behind and above the vapor separator 24.

  The vapor separator 24 separates fuel vapor contained in the liquid fuel and guides only this fuel vapor to the intake manifold 31 for recombustion. As shown in FIGS. 4 and 5, the vapor separator 24 and the canister 51 are connected by a fuel vapor hose 71 for supplying the fuel vapor separated by the vapor separator 24. A canister protection valve 72 is disposed in the middle of the fuel vapor hose 71. The canister 51 adsorbs and holds the introduced fuel vapor.

  Further, as shown in FIGS. 4 and 5, the canister 51 and the intake manifold 31 are connected by a purge pipe 73. A purge valve 74 is provided in the middle of the purge pipe 73. An air vent pipe 75 is further connected to the canister 51, and the tip of the air vent pipe 75 opens into the engine cover 5. An air vent valve 76 is provided in the middle of the air vent pipe 75.

  FIG. 6 is a block diagram of the evaporated fuel processing apparatus of the present embodiment. The purge valve 74 is a valve for controlling the discharge of the evaporated fuel adsorbed by the canister 51 to the intake device. The air vent valve 76 is a valve for controlling the introduction of outside air into the canister 51. The canister protection valve 72 is closed to prevent the liquid fuel from flowing from the vapor separator 24 to the canister 51. The canister protection valve 72, the purge valve 74, and the air vent valve 76 are all constituted by electromagnetic valves and are controlled by the ECU 63. The ECU 63 includes a CPU, a storage device, a timer, and the like (all not shown).

  The air vent valve 76 sucks the evaporated fuel adsorbed by the canister 51 when a main key (engine key) (not shown) is turned on and the engine 2 is started and the intake manifold 31 reaches a predetermined negative pressure. When it becomes easy, it is controlled to open. In parallel with controlling the fuel injection by the injector 25, the ECU 63 controls the opening and closing of the purge valve 74 to adjust the supply of the fuel vapor to the intake manifold 31, and the optimal air-fuel ratio by the supply of the fuel vapor by both. Control to be As fresh air passes through the canister 51 via the air vent valve 76, the adsorption performance of the evaporated fuel of the canister 51 is regenerated.

  The air vent valve 76 and the purge valve 74 are closed when the main key is turned off, the engine 2 is stopped, and the power supply is interrupted. This prevents the evaporated fuel from being discharged to the outside.

  The canister protection valve 72 can be opened when the main key is turned on, but can be controlled to close depending on the calculated inclination angle φ even when the main key is turned on. That is, the ECU 63 uniformly controls the canister protection valve 72 to be closed when the absolute value | φ | of the inclination angle φ reaches a predetermined angle (for example, 35 ° or more). Thereby, even if the outboard motor 1 is in a posture that is largely inclined with respect to the horizontal state, liquid fuel is prevented from being mainly immersed directly into the canister 51 from the vapor separator 24. Here, the predetermined angle is set such that the liquid fuel can easily flow from the vapor separator 24 to the canister 51 according to the arrangement relationship between the vapor separator 24 and the canister 51.

  The canister protection valve 72 is finally closed when the main key is turned off and the engine 2 is stopped. However, before that, the ECU 63 maintains the opening control of the canister protection valve 72 for a predetermined time after the engine is stopped by the timer function. Thereby, a large amount of evaporated fuel generated in the vapor separator 24 after the engine is stopped is processed by the canister 51.

  The fuel and fuel vapor supply paths will be described.

  The low-pressure fuel pump 20 (see FIG. 4) sucks the liquid fuel in the fuel tank 38 through the inlet 45, the fuel hose 23, and the low-pressure fuel filter 19 (see FIG. 4), and is built in the vapor separator 24. Guide to the vapor separator tank. The vapor separator 24 separates fuel vapor from the supplied fuel. The liquid fuel from which the fuel vapor has been separated is pumped to the high-pressure fuel filter 18 at a predetermined pressure by a high-pressure fuel pump built in the vapor separator 24, and each injector 25 (see FIG. 4) via a delivery pipe 21 (see FIG. 4). From the corresponding intake port and then introduced into the corresponding cylinder and combusted.

  On the other hand, when the canister protection valve 72 is controlled to open by the control of the ECU 63, the fuel vapor separated by the vapor separator 24 is supplied to the canister 51 via the fuel vapor hose 71 and the canister protection valve 72. The canister 51 adsorbs and holds the introduced fuel vapor. The fuel vapor stored in the canister 51 is introduced into the purge valve 74 via the purge pipe 73. When the purge valve 74 is controlled to be opened by the control of the ECU 63, the fuel vapor is purged while taking in the air in the engine cover 5 through the air vent pipe 75 and the air vent valve 76 and supplied to the intake manifold 31. . Thereafter, it is mixed with the fuel injected from each injector 25, introduced into each cylinder, and burned.

  According to the present embodiment, the canister protection valve 72 is disposed between the vapor separator 24 and the canister 51 so that liquid fuel can be prevented from flowing into the canister 51 from the vapor separator 24. It is possible to prevent the function of the canister 51 from being deteriorated due to the immersion of fuel.

  In addition, based on the inclination angle signal θMOT of the outboard motor angle detection device 83 and the detection signal θB of the hull angle detection device 90, the inclination angle φ with respect to the horizontal state (horizon line) of the main body 1A of the outboard motor 1 is calculated. Since the opening and closing of the canister protection valve 72 is controlled based on the inclination angle φ, the vapor separator generated by the change in the attitude of the outboard motor 1 is processed by the canister 51 while processing the evaporated fuel generated in the vapor separator 24 during engine operation. It is possible to prevent the liquid fuel from flowing into the canister 51 from 24. Therefore, even when the attitude of the main body 1A of the outboard motor 1 greatly fluctuates during tilt-up, sudden acceleration / deceleration, rough wave navigation, etc., the inflow of liquid fuel into the canister 51 is reliably prevented. be able to. In particular, since not only the outboard motor 1 alone but also the inclination of the hull 70 is taken into account, the substantial inclination angle of the main body 1A is accurately detected and the opening and closing of the canister protection valve 72 is controlled. Inflow of fuel can be prevented more appropriately.

  Even if the main switch is turned off, the canister protection valve 72 is kept open for a predetermined time after the engine is stopped, so that it is possible to ensure the processing of the evaporated fuel generated in the vapor separator after the engine is stopped.

  Further, since the evaporative fuel processing apparatus is not always operated, but is operated only during engine operation, it is possible to suppress consumption of a battery (not shown).

  In the present embodiment, the canister 51 is always positioned above the vapor separator 24 even if it is tilted up. Therefore, the canister protection valve 72 does not have to be relied upon (for example, the canister protection valve Even if 72 is a malfunction or failure), it is difficult for the liquid fuel to flow into the canister 51. However, even when the canister 51 has to be disposed below the vapor separator 24 due to restrictions on the arrangement space or the like, the canister protection valve 72 is controlled to open and close based on the inclination angle φ as described above. Thus, the inflow of liquid fuel can be prevented. Therefore, from this point of view, the arrangement restriction of the canister 51 and the vapor separator 24 is alleviated.

  Note that the configurations of the outboard motor angle detection device 83 and the hull angle detection device 90 that detect the attitude of the outboard motor 1 are not limited to those illustrated. For example, for the outboard motor angle detection device 83, as described in Japanese Patent Publication No. 6-78079, the trim sensor is disposed at a position where the entire region of the trim region and the tilt region can be detected, A trim sensor may be used instead of the outboard motor angle detection device 83. By doing so, the configuration can be simplified by sharing the sensor.

  Further, the outboard motor angle detection device 83 can detect the angle of the main body 1A linearly, but is not limited to this, and may be a sensor that can detect the angle step by step, preferably as many steps as possible. For example, a configuration similar to that of the tilt limit switch may be improved, a plurality of switches that output signals at different angles may be provided, and the current angle of the main body 1A may be detected stepwise based on the output of each switch. In that case, you may comprise so that the said outboard motor angle detection apparatus may serve as a tilt limit switch.

  Although the outboard motor angle detection device 83 is an electronic control type controlled by the ECU 63, the tilt of the main body 1A is inclined from the viewpoint of simplifying the configuration as long as it is limited to preventing liquid fuel from flowing into the canister 51. It may be configured to mechanically close when a predetermined angle is reached. For example, a diaphragm type, a float type, or the like may be employed.

  Note that the outboard motor angle detection device 83 and the hull angle detection device 90 detect inclination in the front-rear direction, but are not limited thereto. For example, the horizontal inclination of the main body 1A and the rotational position of the main body 1A itself in the steering direction are detected, and the posture of the main body 1A is comprehensively determined based on a part or all of these detection signals, and according to the posture. The canister protection valve 72 may be controlled to open and close.

  Note that the hull angle detection device 90 may be eliminated from the viewpoint of simplifying the configuration. In that case, when controlling the opening and closing of the canister protection valve 72 based on the tilt angle signal θMOT from the outboard motor angle detection device 83, a margin corresponding to the above θB is provided in consideration of the tilt of the hull 70, so that the liquid fuel Inflow prevention to the canister 51 can be realized.

1 is a right side view of an outboard motor to which an evaporated fuel processing apparatus according to an embodiment of the present invention is applied. Side view of the outboard motor angle detection device provided between the clamp bracket and the swivel bracket and its peripheral portion showing the tilt-down state of the outboard motor main body (FIG. 1A), and the side surface showing the state during the tilt-up It is a figure (figure (b)). It is a side view (Drawing (a)) and composition of the hull angle detecting device (Drawing (b) and (c)) showing composition of a hull angle detecting device which detects a tilt angle of a hull. It is a right view of the engine part of an outboard motor. It is a top view which shows the inside of the front half part of an outboard motor. It is a block diagram of the evaporative fuel processing apparatus of this Embodiment.

Explanation of symbols

1 Outboard motor 24 Vapor separator 31 Intake manifold (intake device)
51 canister 63 ECU (control means)
72 Canister protection valve 74 Purge valve 76 Air vent valve 83 Outboard motor angle detection device (outboard motor attitude detection means)
90 Hull angle detection device (hull attitude detection means)

Claims (4)

A canister that introduces the evaporated fuel in the vapor separator and adsorbs the introduced evaporated fuel;
A purge valve provided between the intake device and the canister for controlling the discharge of the evaporated fuel adsorbed by the canister to the intake device;
An air vent valve for controlling the introduction of outside air into the canister;
A canister protection valve provided between the vapor separator and the canister to prevent liquid fuel from flowing from the vapor separator to the canister ;
Control means for controlling the opening and closing of the purge valve, the air vent valve and the canister protection valve,
The purge valve, the air vent valve, and the canister protection valve are all configured as electromagnetic valves that are closed when the main switch is turned off, and the control means is configured to operate the canister protection valve even when the main switch is turned off. Is controlled to be closed after being kept open for a predetermined time after the engine is stopped . Before SL has outboard posture detection means to detect the attitude of the outboard motor, before Symbol control means, the canister protection based on the attitude of the outboard motor that is detected by the outboard motor position detecting means evaporative fuel processing system for an outboard motor of claim 1 Symbol mounting, characterized in that opening and closing control of the valve. Before SL control means, when the posture of the outboard motor that is detected by the outboard motor position detecting means becomes a predetermined posture, as claimed in claim 2, characterized in that the closing control of the canister protection valve Evaporative fuel processing equipment for outboard motors. Hull attitude detection means for detecting the attitude of the hull mounted with the outboard motor, and the control means is configured to be horizontal based on a detection result of the outboard motor attitude detection means and a detection result of the hull attitude detection means. The outboard motor according to claim 3 , wherein an inclination angle of the outboard motor with respect to a state is detected, and the canister protection valve is controlled to be closed when the detected inclination angle exceeds a predetermined angle. Evaporative fuel processing device.

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