JP2707442B2 - Outboard motor - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crankshaft of an engine body which is placed upright, a flywheel magnet is arranged at the upper end of the crankshaft, and synchronized with the rotation speed of the engine. Outboard motor including an ignition signal generating mechanism for generating an ignition signal by performing the control, a throttle valve opening mechanism, a control device for correlatively controlling the ignition timing and the throttle valve opening, and an operating member for operating the control device It is about. 2. Description of the Related Art An outboard motor usually does not have a clutch mechanism. However, as disclosed in Japanese Patent Application Laid-Open No. 61-89978, an ignition timing control device is used when the engine is rotating at a low speed, that is, the throttle valve opening. In some cases, the angle is retarded when the value is small, and is advanced when the opening of the throttle valve is large at high speed rotation. In this device: After the start, the frame base for changing the ignition timing to the advanced side is rotated in conjunction with the opening of the throttle valve for controlling the air-fuel mixture. When the throttle valve is fully closed, the flamagbase is rotated in the opposite direction to change the ignition timing to the retard side while maintaining the correlation between the throttle valve opening and the ignition timing when the throttle valve is opened. . 2. As a result, the combustion from low to high speed is completed before the exhaust port opens, and attempts have been made to reduce the adverse effects of ignition and ignition during the compression stroke, thereby improving the output or reducing the fuel consumption. I have. [0003] As described above, the outboard motor usually does not have a clutch mechanism, so that when the throttle is fully decelerated and the throttle is fully closed, an excessive load is applied to the drive shaft. In addition, the flywheel follows the rapid movement of the throttle due to its inertia force and the engine speed does not drop, so when it is fully closed, it tends to be delayed from the regular advance angle, and backfire occurs and it is easy to stall. There is. The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to secure an appropriate relationship between the throttle and the advance angle at the time of full closing of sudden deceleration. It is an object of the present invention to provide a highly reliable outboard motor that reduces the load applied to the drive shaft when the throttle is fully closed and has a small engine stall. [0005] In order to achieve the above object, an outboard motor according to the present invention has a crankshaft of an engine main body set up, and a flywheel magnet disposed at an upper end of the crankshaft. An ignition signal generating mechanism for generating an ignition signal in synchronization with the rotation speed of the engine, a throttle valve opening mechanism, a first control device for correlating the ignition timing and the throttle valve opening, and a control device. In an outboard motor having an operating member to be operated, an ignition timing at the time of rapid deceleration is provided between the ignition signal generating mechanism and the throttle valve opening mechanism in a portion close to the first control device on one side of the engine body. A second control device is provided which changes the correlation between the throttle valve opening degrees in comparison with that at the time of slow deceleration to make it correspond to the engine speed. Embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a side view of an outboard engine to which the present invention is applied, partially cut away, FIG. 2 is a cross-sectional view of a control link taken along the line II-II of FIG. 1, and FIG. FIG. 4 is an electric circuit diagram showing the ignition device, FIG. 5 is a diagram showing ignition advance characteristics, and FIG. 6 is a detailed sectional view of the intake system. The outboard motor engine 10 includes an engine body 11
And upper and lower intake manifolds 12, upper and lower carburetors 13, and intake boxes 14. As shown in FIG.
A venturi portion 16 is formed in the intake passage 15 of
A main nozzle 20 is provided. Venturi part 1
6 is a choke valve 21 on the upstream side and a throttle valve 2 on the downstream side.
2 are provided. 23 is a float chamber, 24 is an idle port as a low-speed fuel supply port, and 25 is a bypass port. Reference numeral 26 denotes a lead valve arranged in the middle of the intake passage 30 to enable compression of the crank chamber. As shown in FIG. 1, the throttle valve 22 is provided with a rotating roller 31. A flywheel 33 is fixed to the upper end of the vertically placed crankshaft 32, and a flamag base 35 rotatable along a guide plate 34 attached to the engine body 11 is provided inside the flywheel 33. Are located. A pulsar coil 40 is fixed to the plate 36 fixed to the frame base 35. On the other hand, the charge coil 41
Is attached to the engine body 11. The coils 40 and 41 are generated by rotation of the magnets 42 and 43 to which the flywheel 33 is fixed. On one side of the engine body 11, a mechanical control device 44 as a first control device for correlating the throttle valve opening and the ignition timing is mounted. The mechanical control device 44 mainly includes a first control lever 46 to which a throttle wire 45 is attached, and a second control lever 51 connected to the lever 46 by a first torsional spring 50. , Second on this lever 51
Connected by a torsion spring 52,
Base lever for rotating the base 35 through the link 53
54. Reference numeral 55 denotes a dashpot as a second control device. Reference numeral 56 denotes a collar, 60 denotes a mounting bolt, 61 denotes a bush, and 62 denotes a washer. And
The first torsional spring 50 has a higher spring constant than the second torsional spring 52. The springs 50 and 52 are compressed so that the levers do not fall down when they rotate. When the throttle grip, which is an operating member (not shown), is turned to the fully open side, the first control lever 46 rotates rightward in the figure via the throttle wire 45.
By this rotation, the accelerator cam 65 rotates around the bolt 66 via the ball joint 63 and the rod 64 fixed to the first control lever 46. As a result, the cam surface 65a of the accelerator cam 65 presses the roller 31, and the throttle valve 22 rotates clockwise to increase the opening.
Reference numeral 70 denotes a rod connecting the throttle valves 22 of the upper and lower carburetors 13. Meanwhile, at the same time, the first control spring 50 causes the second control lever 51 and the second control lever 51 to operate.
The lever 51 is pushed by the protrusion 51 a of the control lever 51, and rotates clockwise until the base rotating lever 54 contacts the stopper 71. At the same time, the rod 53 causes the flammag base 35 to rotate counterclockwise as viewed from above the flywheel 33. On the other hand, the crankshaft 32 is rotating clockwise. That is, the timing at which the pulsar coil 40 is energized is advanced, and the ignition timing is advanced. In a state where the ignition advance amount is regulated by the stopper 71, the first control lever 46 can rotate rightward by bending the first torsional spring 50, and the throttle valve 22 is fully opened. Becomes At this time, the rotation of the first control lever 46 is rotated by the lever 4.
6 is regulated by the contact between the protrusion 46 a provided on the base 6 and the stopper 72. When the first control lever 46 is rotated leftward in the figure by the throttle wire 45, the cam accelerator 65 is also rotated leftward, and the throttle valve 22 is rotated to the closing side by a spring (not shown). The projection 46a and the second control
When the throttle valve 22 is fully opened, the projection 51b provided on the lever lever 51 is separated by the action of the stopper 71. However, as the first control lever 46 rotates counterclockwise, the first torsional spring 50 is twisted. The first control lever 46 and the second control lever 51 rotate counterclockwise as a unit. At this time, the projection 51a and the base rotating lever 5
Reference numeral 4 is kept in contact by the weak elastic force of the second torsional spring 52 and the electromagnetic force generated by clockwise rotation when viewed from above the flywheel 33. That is, the base rotation lever 54 also rotates counterclockwise to retard. While the throttle valve opening is decreasing, there is an opening at which the rate of fuel supply from the main nozzle is smaller than the rate of fuel from the low-speed fuel supply port. When the levers 46, 50, 54 rotate to the left until the opening degree is reached, the base rotation lever 54 contacts the push rod 73 of the dashpot 55. Dashpot 55 is a base
The rotation lever 54 acts to slow down the rotation speed. That is, the faster the deceleration speed, the slower the retard speed. The rotation of the first control lever 46 stops at the fully closed position while the protrusion 51a contacts the stopper 74. On the other hand, the rotation of the base rotation lever 54 stops at the maximum retard position by contacting the stopper 75. A dashpot 55 as a second control device
3 is shown in FIG. 80 is an orifice, 81 is a body to which a one-way valve 82 is attached, 83 is a filter, 84
Is a cap having an air communication port (not shown), and 85 is a body caulked together with a diaphragm 86 to a body 81.
It is. Reference numeral 90 denotes a stay welded to the body 85, and 91 denotes a guide caulked by the stay 90, and 92 denotes a push housed in the guide 91 and holding the push rod 73 slidably. 93 and 94 are diaphragm 8
6 and two rods for connecting the push rod 73
It is. The spring 95 draws air from both the orifice 80 and the one-way valve 82 into the diaphragm chamber 96 and causes the push rod 73 to protrude. However, the spring 95
Are set smaller than the spring load of the first torsional spring 50. 97 is a mounting bolt, 10
Reference numeral 0 denotes a spring receiver, 101 denotes a circlip, and 102 denotes a rubber boot. 103 is an atmosphere communication hole, and 104 is a one-way valve passage. The ignition device is mainly composed of the pulsar coil 40, the charge coil 41, and the mechanical control device 44 described above.
, An ignition control device 105, an ignition coil 106, and an ignition plug 110 arranged on a side surface of the engine body 11. The ignition control device 105 controls the CDI as shown in FIG.
After the voltage generated by the charge coil 41 is rectified by the diode 111 and charging of the ignition capacitor 112 is started, the SCR 113 receives the ignition timing signal generated by the pulser coil 40 (ignition timing detection unit). The gay
At the same time, the electric charge stored in the capacitor 112 is rapidly released through the primary side of the ignition coil 106, thereby generating a high voltage on the secondary side and sparking the spark plug 110. generate. The mechanical control device 44
By changing the position of the pulsar coil 40 around the crankshaft, a desired ignition timing characteristic is given. As shown in FIG. 5, the relationship between the throttle opening and the ignition timing is as shown at 114 during acceleration or slow deceleration. Sudden deceleration in which the speed of deceleration is fast, that is, an ignition timing characteristic of 115 when the closing speed of the throttle valve 22 is fast, and 116 when the speed is even faster is given. This is because the speed of the air amount passing through the orifice 80 does not follow even if the push rod 73 moves fast. The point 120 in the figure is the stopper 71 and the base rotating lever.
Reference numeral 122 denotes the ignition timing when the abutment occurs, 122 denotes the ignition timing when the fully opened stopper 72 operates, and 123 denotes the ignition timing when the fully closed stopper 75 operates. The point 121 is that the mounting hole 90a of the dashpot 55 to the engine body 11 is a long hole,
By moving the dashpot 55 left and right with
It can be moved left and right in FIG. FIG. 7 shows an adjusting screw 1 that can change the opening area of the orifice 80 in order to make this characteristic variable.
24 shows a dashpot provided with 24. This allows adjustment for each engine and increases versatility. FIG. 8 is a circuit diagram showing an ignition timing control device at the time of sudden deceleration electrically configured as a second embodiment. In this embodiment, the mechanical control device 44 is removed, and the ignition timing is set electrically. That is, the pulsar coil 40 is fixed to the engine body 11. That is, while the signal of the fixed crankshaft angle is picked up from the pulsar coil 40, the signal of the rotation speed sensing circuit of 130 is received, and the ignition timing control circuit of 131 and the adjustment circuit 132 increase the higher the engine speed. S
The gate of CR113 is turned on. Conversely, the gate of the SCR 113 is made conductive at a later time as the engine speed is lower. The ignition timing control circuit 131 also senses the speed of deceleration, and thereby controls the speed of retard as shown in FIG. The one shown by the two-dot chain line shows the third embodiment in which the throttle valve sensor is attached to the throttle valve shaft, and the deceleration is sensed by the change in the throttle valve opening. FIG. 9 is a diagram showing ignition advance characteristics as another example in the second and third embodiments. In this,
As the degree of rapid deceleration increases, the advanced ignition timing is held. As a result, the delay before shifting to the steady state is delayed. FIG. 10 is a diagram showing still another example and ignition advance characteristics. In this case, at the time of sudden deceleration, the angle is temporarily advanced instead. In any of the above-described embodiments, when the engine speed is decelerated to decrease the engine speed, and when the rapid deceleration is detected, the ignition timing and the throttle valve are controlled by the dashpot 55 or the ignition timing control circuit 131 as the second control device. Reduce the flywheel speed to the normal engine speed when the throttle valve is fully closed by fully closing the throttle valve, assuming that the correlation between the opening degrees is changed compared to that at the time of slow deceleration and corresponding to the engine speed. be able to. Therefore, when the throttle is fully closed, an appropriate relationship between the throttle and the advance angle can be secured, and when the throttle is fully closed, the load applied to the drive shaft can be reduced and engine stall can be avoided. According to the present invention, the correlation between the ignition timing at the time of rapid deceleration and the throttle valve opening is changed as compared with that at the time of slow deceleration to correspond to the engine speed.
By the time the throttle valve is fully closed, the speed of the flywheel can be reduced to the normal engine speed when the throttle is fully closed. In this case, the outboard motor can reduce the load on the drive shaft and avoid engine stall. In addition, since the second control device is disposed at a position close to the first control device, the operation transmission from the first control device to the second control device is simplified, and a highly reliable outboard Machine.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view showing an engine for an outboard motor to which the present invention is applied, partially cut away. FIG. 2 is a control diagram taken along the line II-II in FIG.
It is sectional drawing of lulink. FIG. 3 is a sectional view of the ignition timing control device at the time of rapid deceleration. FIG. 4 is an electric circuit diagram showing an ignition device. FIG. 5 is a diagram showing ignition advance characteristics. FIG. 6 is a detailed sectional view of an intake system. FIG. 7 is a partial sectional view of a dashpot according to another embodiment. FIG. 8 is a circuit diagram showing an ignition timing control device at the time of rapid deceleration according to the second embodiment and the third embodiment. FIG. 9 is a diagram showing ignition advance characteristics as another example. FIG. 10 is a diagram showing ignition advance characteristics as still another example. [Description of Signs] 22 Throttle valve 32 Crankshaft 33 Flywheel 35 Flamage base 40 Pulser coil 42, 43 Flywheel magnet 44 Mechanical control device (first control device) 46 First control lever 50 No. 1 torsional spring 51 2nd control lever 52 2nd torsional spring 54 base rotation lever 55 dashpot (second control device) 65 accelerator cam 105 ignition control device 106 ignition coil 110 ignition plug 130 Revolution speed sensing circuit 131 Ignition timing control circuit 132 Adjustment circuit 133 Throttle opening sensor

Claims (1)

(57) [Claims] A crankshaft of the engine body is set up, a flywheel magnet is arranged at the upper end of the crankshaft, and an ignition signal generating mechanism for generating an ignition signal in synchronization with the rotation speed of the engine; a throttle valve opening mechanism; In an outboard motor including a first control device that performs correlation control of an ignition timing and a throttle valve opening degree, and an operating member that operates the control device, an engine is provided between the ignition signal generation mechanism and the throttle valve opening mechanism. In a portion close to the first control device on one side of the main body, the correlation between the ignition timing and the throttle valve opening at the time of rapid deceleration is changed as compared with that at the time of slow deceleration, so as to correspond to the engine speed. An outboard motor, comprising: a control device.