JP2009255770A - Outboard motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an outboard motor capable of keeping constant engine speed and facilitating steering operation by a simple constitution. <P>SOLUTION: The outboard motor 10 electrically controls the opening/closing operation of a throttle valve 53 so as to set the actual rotational speed Nr of an engine 14 for driving a propeller 18 to a target value. The outboard motor 10 comprises a constant speed setting unit 44 provided at a steering handle 41 to perform the manipulated operation, a turnable grip 42 provided at a fore end of the steering handle 41, a grip operational quantity detection unit 43 for detecting the operational quantity θ of the grip 42, and a control unit 51 which sets the target rotational speed according to the operational quantity detected by the grip operational quantity detection unit 43 and controls the opening/closing operation of the throttle valve 53 so that the actual rotational speed Nr is set to the target value. The control unit 51 performs the control of maintaining the target rotational speed immediately before receiving an electrical set signal when the electrical set signal is received from the constant speed setting unit 44. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a technique for controlling the rotational speed of an engine in an outboard motor.

In a small vessel, an outboard motor is mounted at the rear of the hull. The outboard motor includes a substantially horizontal bar-shaped steering handle. Various types of outboard motors are known (see, for example, Patent Document 1).
JP 2006-205789 A

  The outboard motor known from Patent Document 1 has a rotatable grip at the tip of a steering handle. The opening degree of the throttle valve can be adjusted by turning the grip. As a result, the rotational speed of the engine changes. The ship operator performs two operations simultaneously with one hand, while adjusting the opening degree of the throttle valve by further rotating the grip while grasping and gripping the grip. It takes skill to keep the rotational speed constant while the ship operator steers for a long time.

  For this reason, the outboard motor known from Patent Document 1 is provided with a mechanical handle adjustment mechanism so that the grip does not rotate during steering. As a result, the rotational speed of the engine can be kept constant relatively easily. However, since the grip is prevented from rotating by a mechanical configuration, the configuration is complicated and there is room for further improvement.

  It is an object of the present invention to provide a technique that can keep the rotational speed of an engine constant with a simple configuration and that can be easily operated.

  In the invention according to claim 1, in the outboard motor that electrically controls the opening and closing of the throttle valve so that the actual rotational speed of the engine that drives the propeller matches the target rotational speed, the steering handle is provided and the manual operation is performed. A possible constant speed setting unit, a rotatable grip provided at the tip of the steering handle, a grip operation amount detection unit for detecting an operation amount of the grip, and the grip operation amount detection unit detected by the grip operation amount detection unit. A control unit that sets the target rotational speed according to an operation amount and controls the opening and closing of the throttle valve so that the actual rotational speed matches the target rotational speed. When the electric setting signal is input from the constant speed setting unit, the control is performed so as to maintain the target rotational speed at the time when the input is started. And butterflies.

  According to a second aspect of the present invention, in the first aspect, the control unit is configured to perform control so that the maintained target rotation speed is maintained as it is when the input of the setting signal is completed. It is characterized by that.

  According to a third aspect of the present invention, in the second aspect, when the operation amount is changed after the input of the setting signal is completed, the control unit changes the operation amount changed from the maintained target rotational speed. It is the structure which controls so that it may change gradually to the target rotational speed according to this.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the constant speed setting unit includes a manual operation switch arranged in the vicinity of the grip.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the steering handle includes a display unit that displays the actual rotational speed and the target rotational speed. To do.

  In the invention according to claim 1, the steering handle includes a rotatable grip and a constant speed setting portion. The control unit sets a target rotation speed in accordance with the grip operation amount detected by the grip operation amount detection unit, and controls opening and closing of the throttle valve so that the actual rotation speed matches the target rotation speed. The constant speed setting unit generates an electrical setting signal in accordance with the operation of the vessel operator. When the electrical setting signal is input from the constant speed setting unit, the control unit maintains the target rotational speed when the input is started. In other words, the engine speed can be kept constant by a simple operation by simply operating the constant speed setting unit. For this reason, a ship can be maneuvered easily. Moreover, since the constant speed setting unit only generates an electrical setting signal in response to the operation of the vessel operator, a simple configuration is sufficient.

  In the invention according to claim 2, the setting signal issued from the constant speed setting unit to the control unit ends when the ship operator releases the constant speed setting unit. At this point, the control unit continues to maintain the maintained target rotation speed. For this reason, the target rotational speed does not change suddenly when the constant speed setting unit is released. Since the engine rotation speed does not change suddenly, the ship operator can operate the ship more stably.

  In the invention according to claim 3, the target rotational speed changes according to the amount of operation of the grip by turning the grip after the ship operator releases the constant speed setting unit. In this case, the control unit performs control so as to gradually change from the target rotation speed maintained until now to the target rotation speed corresponding to the changed operation amount. In this way, the target rotational speed changes only when the operator consciously turns the grip after releasing the constant speed setting unit. Moreover, the target rotational speed changes gradually. For this reason, the ship operator can perform ship operation more stably.

  In the invention according to claim 4, since the constant speed setting unit is configured by the manual operation switch arranged in the vicinity of the grip, the configuration of the constant speed setting unit can be further simplified.

  In the invention according to claim 5, since the steering handle is provided with a display unit for displaying the actual engine speed and the target engine speed, the engine speed is always easy to visually check when the operator is steering. Can be confirmed.

The best mode for carrying out the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is a side view of an outboard motor according to the present invention. FIG. 2 is a plan view of the steering handle shown in FIG. As shown in FIG. 1, the outboard motor 10 includes a mount case 11, an extension case 12, a gear case 13, an engine 14, a drive shaft 15, a gear mechanism 16, a propeller shaft 17, a propeller 18, and an outboard motor mounting mechanism 19. Become.

  The mount case 11 is a so-called engine support case in which the engine 14 is attached to the upper surface. The extension case 12 is attached to the lower part of the mount case 11. The gear case 13 is attached to the lower part of the extension case 12. The engine 14 is a vertical engine (for example, a single cylinder engine), in which the axis of the cylinder 21 is oriented horizontally (substantially horizontal) and the crankshaft 22 is oriented vertically. The drive shaft 15 is housed in the extension case 12, extends downward from the crankshaft 22, and transmits the power of the engine 14 to the propeller 18 via the gear mechanism 16 and the propeller shaft 17.

  The engine 14 is covered with a lower undercase 31 and an upper engine cover 32. The engine cover 32 has a fresh air inlet 32a at the top. Outside air is taken into the engine cover 32 from the fresh air inlet 32a. Further, the engine cover 32 houses therein a throttle valve 53 for the engine 14.

  The outboard motor mounting mechanism 19 fixes the outboard motor 10 to the hull Si, swings the outboard motor 10 left and right in plan view around the swivel shaft 19a, and swivels around the tilt shaft 19b. The outboard motor 10 including the shaft 19a can be flipped up in the clockwise direction in the figure.

  Incidentally, the undercase 31 includes a substantially horizontal bar-shaped steering handle 41 on the side of the front portion (the hull Si side). The steering handle 41 (tiller handle 41) can be set to a substantially horizontal use position indicated by a solid line and a substantially vertical storage position by swinging counterclockwise from the use position.

As shown in FIGS. 1 and 2, the steering handle 41 includes a grip 42, a grip operation amount detection unit 43, a constant speed setting unit 44, and a display unit 45.
The grip 42 is disposed at the tip of the bar-like steering handle 41 and is attached to be rotatable around the axis CL of the steering handle 41. The grip operation amount detection unit 43 detects an operation amount θ (not shown) when the grip 42 is rotated, and is disposed inside the steering handle 41. The grip operation amount detection unit 43 includes a variable resistor that generates a voltage signal proportional to the operation amount θ (operation angle θ) of the grip 42.

  The constant speed setting unit 44 is set when the operator wants to maintain the rotational speed of the engine 14 at an arbitrary constant value, and includes a manual operation switch operated by the operator. Since the constant speed setting unit 44 is configured by the manual operation switch disposed in the vicinity of the grip 42, the configuration of the constant speed setting unit 44 can be further simplified.

  This manual operation switch consists of a rocker switch, for example. This rocker switch is also called a seesaw switch or a tumbler switch. More specifically, the constant speed setting unit 44 including a rocker switch is a switch for switching the connection circuit by pressing one side of the operation knob 44a that performs a seesaw operation. The operation knob 44a is configured to switch between two positions, an OFF position OFF and an ON position ON that tilts by performing a seesaw operation from the OFF position OFF, and can be switched even if the operation force is removed after the operation. Self-holding in a different position.

  The switch signal generated by the constant speed setting unit 44 includes two signals, an off signal and an on signal. Specifically, when the operation knob 44a is positioned at the OFF position OFF, the constant speed setting unit 44 issues an OFF signal (release signal). When the operation knob 44a is at the ON position ON, the constant speed setting unit 44 issues an ON signal (setting signal). Hereinafter, the constant speed setting unit 44 is appropriately referred to as a “cruise switch 44”.

  The constant speed setting unit 44 is provided at a position different from the grip 42 in the steering handle 41. For example, the constant speed setting unit 44 is fixed to the distal end surface of the steering handle 41. For this reason, for example, the constant speed setting unit 44 can be operated by the thumb of the hand holding the grip 42.

  As shown in FIG. 1, it is preferable to arrange the constant speed setting unit 44 so that the operation knob 44a performs a seesaw operation up and down when the steering handle 41 is in a substantially horizontal use position. With this arrangement, the operation of the operation knob 44a does not change regardless of whether the operator is positioned on the left or right (front and back of the paper in FIG. 1) with respect to the steering handle 41. For this reason, the operability of the operation knob 44a is further enhanced.

The constant speed setting unit 44 may be configured to be disposed near the grip 42 in the steering handle 41. For example, the constant speed setting unit 44 may be disposed closer to the swing base 41a than the grip 42 in the steering handle 41.
Since the constant speed setting unit 44 is provided not on the outboard motor 10 itself but on the steering handle 41, the position of the constant speed setting unit 44 is closer to the operator. For this reason, it is easy for the operator to operate the constant speed setting unit 44.

The display unit 45 is disposed on the steering handle 41 closer to the swing base 41a than the grip 42 and on the upper surface of the handle.
Thus, since the grip operation amount detection unit 43, the constant speed setting unit 44, and the display unit 45 are provided not on the outboard motor 10 itself but on the steering handle 41, they are not easily covered with water.

  FIG. 3 is a schematic system diagram of the outboard motor according to the present invention. As shown in FIG. 3, the outboard motor 10 is characterized by mounting an electronic governor 50 (also referred to as an electric governor or an electronic governor). The electronic governor 50 controls the rotational speed of the engine 14 by automatically adjusting the opening of the throttle valve 53 with the electric motor 52 based on the control signal of the control unit 51. The electronic governor 50 includes a combination of a control unit 51, an electric motor 52, a throttle valve 53, a throttle opening sensor 54, and an engine rotation sensor 55. The throttle opening sensor 54 detects the opening α of the throttle valve 53. The engine rotation sensor 55 detects an actual rotation speed Nr of the engine 14.

  The control unit 51 receives signals from the grip operation amount detection unit 43, the constant speed setting unit 44, the throttle opening sensor 54, the engine rotation sensor 55, and the main switch 56, and controls the engine 14 to perform predetermined control. This is an electronic control unit controlled in a mode, and is composed of a microcomputer, for example. That is, the control unit 51 controls the ignition device 57, sets the target rotation speed Ns according to the operation amount θ (operation angle θ) of the grip 42 detected by the grip operation amount detection unit 43, and The throttle valve 53 is electrically opened and closed via the electric motor 52 so that the actual rotational speed Nr matches the target rotational speed Ns.

  FIG. 4 is a conceptual diagram illustrating a concept in which the control unit illustrated in FIG. 3 increases or decreases the target rotation speed. The conceptual diagram of FIG. 4 represents the characteristic of the target rotational speed Ns with respect to the operational amount θ, with the horizontal axis as the manipulated variable θ of the grip 42 and the vertical axis as the target rotational speed Ns of the engine. The straight line rising to the right in the figure is a target rotational speed characteristic line and shows that the target rotational speed Ns changes according to the operation amount θ.

  According to this conceptual diagram, the target rotational speed Ns is 0 which is the minimum value when the operation amount θ is 0 which is the minimum value, and the target rotational speed Ns which is 100% (maximum angle) when the operation amount θ is the maximum value. It can be seen that the maximum value is Nmax. The target rotational speed characteristic line shown in FIG. 4 can be used as a map when the control unit 51 obtains the target rotational speed Ns according to the operation amount θ.

Further, the control unit 51 shown in FIG. 3 is configured to perform the following three controls.
The first control is to control the target rotational speed Ns at the time when the input is started when an electrical setting signal (ON signal) is input from the constant speed setting unit 44.
The second control is to perform control so that the maintained target rotational speed Ns is maintained as it is when the input of the setting signal is completed.
In the third control, when the operation amount θ of the grip 42 is changed after the input of the setting signal is completed, the maintained target rotation speed Ns is changed to the target rotation speed Ns corresponding to the changed operation amount θ. It is to control to change gradually.

  The electric motor 52 (electric actuator 52) consists of a step motor, for example. The throttle valve 53 is provided in an intake passage 58 for supplying combustion air to the engine 14. The amount of combustion air can be adjusted by the throttle valve 53. The main switch 56 includes an ignition switch for turning on and off the power supply system of the engine 14 and starting the engine 14.

Furthermore, the control unit 51 issues a display command to the display unit 45 to display the above-described target rotation speed Ns and actual rotation speed Nr. 5A and 5B are diagrams illustrating the display unit illustrated in FIG.
The display unit 45 shown in FIG. 5A has a bar-code-like display pattern 45b formed by arranging a plurality of bar-like display segments 45a (including indicator lights) in a horizontal row. Ns and Nr are displayed. The display unit 45 shown in FIG. 5B is configured to display each rotational speed Ns, Nr by a display pattern 45d formed by arranging a plurality of circular display segments 45c (including display lamps) in a horizontal row. To display. These display patterns 45b and 45d are display systems in which the leftmost display segments 45a and 45c display the lowest speed in FIG.

  Further, the display unit 45 includes a control mode display unit 46. The control mode display unit 46 displays the control mode in which the throttle valve 53 is controlled by the control unit 51 shown in FIG. For example, when the control unit 51 controls the throttle valve 53 in the trolling mode (control mode for finely adjusting the rotation speed of the engine 14), the lighting is displayed. Since the ship operator can easily know the current control mode by viewing the control mode display unit 46, an erroneous operation can be prevented.

  Next, a control flow when the control unit 51 (see FIG. 3) is a microcomputer will be described based on FIG. 6 with reference to FIG. FIG. 6 is a control flowchart showing an example of throttle valve control executed by the control unit shown in FIG. When the ship operator operates the main switch 56 to the start position and starts the engine 14 by operating the ignition device 57, and then operates the main switch 56 to the on position, the control unit 51 performs the control flow of FIG. Start controlling. Then, the control part 51 complete | finishes control by switching the main switch 56 to an OFF position. This control flow is a closed-loop control flow that is repeatedly executed every predetermined time, for example, every 20 msec (milliseconds). Hereinafter, the control flow will be described.

  Now, the cruise switch 44 is in an off state. In this state, the boat operator switches the main switch 56 to the on position. When the main switch 56 is turned on, the control unit 51 first performs initial setting and then starts control (step ST01). That is, the system is reset, the first flag Fa and the second flag Fb are set to 0, and the cruise target rotational speed Nc and the reference target rotational speed NL are set to 0 values.

  Next, the target rotational speed Ns of the engine 14 is obtained (step ST02). Specifically, the operation amount θ of the grip 42 is read, and the target rotational speed Ns of the engine 14 is obtained based on the operation amount θ (step ST02). For example, it can be obtained by the map shown in FIG. Further, the target rotational speed Ns may be obtained from the operation amount θ by calculation. Note that the grip operation amount detection unit 43 detects the operation amount θ of the grip 42.

  Next, the actual rotational speed Nr of the engine 14 is read (step ST03). The actual rotation speed Nr (actual rotation speed Nr) is detected by the engine rotation sensor 55. Next, the switch signal of the cruise switch 44 is read (step ST04). Next, it is determined whether or not the switch signal of the cruise switch 44 is off (step ST05). If it is determined in step ST05 that the switch signal is OFF, it is determined whether or not the first flag Fa = 0 (step ST06).

  If the switch signal is off in step ST05 and the first flag Fa = 0 in step ST06, it is determined that the speed control mode is normal, and the normal speed control by the operator is executed. (Step ST07). That is, in step ST07, the boat operator appropriately turns the grip 42 in accordance with the boat maneuvering state, and the actual rotation with respect to the target rotational speed Ns corresponding to the operation amount θ (the speed Ns obtained in step ST02). The control unit 51 controls opening / closing of the throttle valve 53 so that the speed Nr matches. Specifically, the opening and closing of the throttle valve 53 is controlled by driving the electric motor 52 by PID control or the like. The signal of the opening α detected by the throttle opening sensor 54 is sent to the control unit 51 as a feedback signal.

Next, the actual rotational speed Nr is displayed on the display unit 45 shown in FIG. 5 (step ST08). Thereafter, the process returns to step ST02.
Thus, when a series of steps ST02 to ST08 is repeated, the control unit 51 maintains the control in the normal speed control mode.

  Thereafter, when the ship operator turns on the cruise switch 44, the switch signal of the cruise switch 44 is inverted to on. Therefore, in step ST05, it is determined that the switch signal of the cruise switch 44 has been turned on, that is, the setting signal has been input, and as a result, it is determined that the auto-cruise control mode has been entered. Then, it is determined whether or not the first flag Fa = 0 (step ST09).

  If it is determined in step ST05 that the switch signal is on and the first flag Fa = 0 in step ST09, the cruise target rotational speed Nc is changed to the current target rotational speed Ns. After setting (step ST10), the process proceeds to step ST11. Note that the current target rotational speed Ns is the value obtained in step ST02. On the other hand, if it is determined in step ST09 that the first flag Fa = 1, the process proceeds to step ST11 while maintaining the value of the original cruise target rotational speed Nc set before this time.

  Since the auto-cruise control mode has been entered, next, auto-cruise speed control is executed (step ST11). That is, in step ST11, the throttle valve 53 is controlled to open and close so that the actual rotational speed Nr matches the cruise target rotational speed Nc. Specifically, the opening and closing of the throttle valve 53 is controlled by driving the electric motor 52 by PID control or the like. As described above, when the ON switch signal (setting signal) is input from the cruise switch 44, the control unit 51 maintains the target rotational speed Ns (that is, the cruise target rotational speed Nc) when the input is started. To control.

  Next, the cruise target rotation speed Nc (the target rotation speed Ns when the input of the ON signal from the cruise switch 44 is started) and the actual rotation speed Nr are displayed on the display unit 45 shown in FIG. 5 (step ST12). For example, as shown in FIG. 5, the display unit 45 displays the target rotation speed Ns in the display segment 45Ns indicated by the hatching pattern among the plurality of display segments 45a and 45c, and the display indicated by the satin pattern. The segment 45Nr displays the actual rotational speed Nr.

As described above, since the automatic cruise control mode is entered, the first flag Fa is inverted from 0 to 1 (step ST13), and the second flag Fb is inverted from 0 to 1 (step ST14). Thereafter, the process returns to step ST02.
Thus, when a series of steps ST02 to ST05 and steps ST09 to ST14 are repeated, the control unit 51 maintains the control in the auto cruise control mode.

  Thereafter, when the operator returns the cruise switch 44 to the off state again, the switch signal of the cruise switch 44 is inverted to off. For this reason, in step ST05, it is determined that the switch signal of the cruise switch 44 has been turned off, that is, a cancel signal has been input. Next, it is determined whether or not the first flag Fa = 0 (step ST06). In step ST13, the first flag Fa has already been inverted from 0 to 1. Therefore, in step ST06, it is determined that the first flag Fa is inverted from 0 to 1, and as a result, it is determined that the initial stage for returning to the normal speed control mode is entered.

  Since the initial stage for returning to the normal speed control mode has been entered, it is next determined whether or not the second flag Fb = 1 (step ST15). In step ST14, the second flag Fb has already been inverted from 0 to 1. Therefore, in step ST15, it is determined that the second flag Fb is inverted from 0 to 1.

  If it is determined in step ST15 that the second flag Fb = 1, the value of the reference target rotational speed NL is set to the current target rotational speed Ns (step ST16). The reference target rotational speed NL is a value that serves as a reference for determining whether or not the grip 42 has been operated after the ship operator has turned off the cruise switch 44 again. In step ST16, the current target rotational speed Ns is the target rotational speed at the time when the switch signal of the cruise switch 44 is reversed from on to off when the cruise switch 44 is turned off again. It is Ns.

  Next, the second flag Fb is inverted again from 1 to 0 (step ST17), and the process proceeds to step ST18. On the other hand, if it is determined in step ST15 that the second flag Fb = 0, the process proceeds to step ST18 while maintaining the original reference target rotational speed NL.

  Next, it is determined whether or not the target rotational speed Ns matches the reference target rotational speed NL (step ST18). If it is determined in step ST18 that they match (NL = Ns), the same control as in step ST11 is executed, that is, the auto cruise speed control is maintained as it is. As described above, the control unit 51 performs control so that the maintained target rotational speed Ns is maintained as it is when the on-input from the cruise switch 44 is completed.

  Next, the cruise target rotation speed Nc (the target rotation speed Ns when the input is started from the cruise switch 44) and the actual rotation speed Nr are displayed on the display unit 45 shown in FIG. 5 (step ST20). Thereafter, the process returns to step ST02.

Thus, when a series of steps ST02 to ST06 and steps ST15 to ST20 are repeated, the control unit 51 maintains the control in the auto cruise control mode as it is in the initial stage of returning to the normal speed control mode. Keep doing.
When the boat operator turns off the cruise switch 44 (release operation), the ON signal (setting signal) issued from the cruise switch 44 to the control unit 51 ends. At this point, the control unit 51 continues to maintain the maintained target rotation speed Ns as it is. For this reason, the target rotational speed Ns does not change abruptly when the cruise switch 44 is released. Since the rotational speed Nr of the engine 14 does not change abruptly, the vessel operator can perform more stable vessel operation.

  By the way, when the operator operates the grip 42 after turning off the cruise switch 44 as described above, the operation amount θ changes, and as a result, the target rotational speed Ns changes. Therefore, in step ST18, it is determined that the target rotational speed Ns does not match the reference target rotational speed NL (NL ≠ Ns). As a result, it is determined that the normal speed control mode has been entered, and the process proceeds to step ST21. move on.

  Next, the throttle valve 53 is controlled to open and close so that the actual rotational speed Nr matches the target rotational speed Ns corresponding to the changed operation amount θ (step ST21). By the way, in step ST21, the target rotational speed Ns maintained until now is gradually changed to a new target rotational speed Ns corresponding to the changed operation amount θ.

  Here, regarding the “degree of change” that is gradually changed from the maintained target rotational speed Ns to the target rotational speed Ns corresponding to the changed operation amount θ, the change in the target rotational speed Ns per unit time Δt. It is determined by setting the amount (ΔNs / Δt, acceleration / deceleration) small. That is, the rate of change is slower than when the normal speed control mode is executed. The response of the change in the target rotational speed Ns is dull with respect to the operating speed at which the grip 42 is operated. For this reason, the control unit 51 performs control so as to gradually change the maintained target rotational speed Ns to the new target rotational speed Ns corresponding to the changed operation amount θ.

  Next, the target rotation speed Ns and the actual rotation speed Nr are displayed on the display unit 45 shown in FIG. 5 (step ST22). Next, it is determined whether or not the actual rotational speed Nr matches the target rotational speed Ns (step ST23). If it is determined in step ST23 that they do not match, the first flag Fa is left as it is, and the process returns to step ST02. Therefore, a series of steps ST02 to ST06, steps ST15 to ST18, and steps ST21 to ST23 are repeated.

As described above, when a series of steps ST02 to ST06, steps ST15 to ST18, and steps ST21 to ST23 are repeated, the control unit 51 executes control for gently returning to the normal speed control mode. .
By turning the grip 42 after the ship operator releases the cruise switch 44, the target rotational speed Ns changes according to the operation amount θ of the grip 42. In this case, the control unit 51 performs control so as to gradually change from the target rotation speed Ns maintained until now to the target rotation speed Ns corresponding to the changed operation amount θ. Thus, the target rotation speed Ns changes only when the gripper 42 consciously turns the grip switch 44 after the cruise switch 44 is released. In addition, since the target rotational speed Ns gradually changes, the ship operator can perform ship operation more stably.

  On the other hand, if it is determined in step ST23 that they match, the first flag Fa is inverted from 1 to 0 (step ST24), and then the process returns to step ST02. Thereafter, in step ST06, it is determined that the first flag Fa is inverted from 1 to 0, and the process proceeds to step ST07. As a result, the control unit 51 executes control in the normal speed control mode. That is, a series of steps ST02 to ST08 is repeated.

  Next, the operation of the electronic governor 50 described in the control flowchart of FIG. 6 will be described based on FIG. 7 with reference to FIG. FIG. 7 is an explanatory diagram of the operation of the electronic governor and each part shown in FIG. 3, and shows the action of each part in a time chart with the horizontal axis as time.

  When the cruise switch 44 is off, the target rotational speed Ns changes according to the operation amount θ of the grip 42. As a result, the actual rotational speed Nr changes so as to match the target rotational speed Ns. For example, when the operation amount θ increases from the value 0 to the value θ1 before the time elapses from the time 0 to the time point t1, the target rotation speed Ns and the actual rotation speed Nr increase from the value 0 to the value N1. Thereafter, when the operation amount θ maintains the value θ1, the target rotation speed Ns and the actual rotation speed Nr maintain the value N1.

  Thereafter, when the cruise switch 44 is turned on at time t2, the target rotational speed Ns maintains the value N1 at time t2. For this reason, the actual rotational speed Nr also maintains N1 as it is. When the cruise switch 44 is in the on state, the target rotational speed Ns does not change even if the operation amount θ of the grip 42 changes.

  Thereafter, even if the cruise switch 44 is turned off at time t3, if the operation amount θ of the grip 42 does not change, the target rotational speed Ns maintains the value N1 at the time t2. For this reason, the actual rotational speed Nr also maintains N1 as it is.

  Thereafter, from time t4 to time t5, the operation amount θ of the grip 42 changes from the value θ1 to the value θ2. On the other hand, the target rotation speed Ns gradually changes from N1 to N2 from time t4 to time t6. The time from t4 to t6 is longer than the time from t4 to t5.

  The above description is summarized as follows. The steering handle 41 includes a rotatable grip 42 and a constant speed setting unit 44 (cruise switch 44). The control unit 51 sets the target rotation speed Ns according to the operation amount θ of the grip 42 detected by the grip operation amount detection unit 43, and the actual rotation speed Nr matches the target rotation speed Ns. The throttle valve 53 is controlled to open and close. Further, the constant speed setting unit 44 issues an electrical setting signal (ON signal) in accordance with the operation of the vessel operator. When the electrical setting signal is input from the constant speed setting unit 44, the control unit 51 maintains the target rotational speed Ns at the time when the input is started. That is, the rotation speed Nr of the engine 14 can be kept constant by a simple operation that only operates the constant speed setting unit 44. For this reason, a ship can be maneuvered easily. In addition, the constant speed setting unit 44 only emits an electrical setting signal in accordance with the operation of the vessel operator, and thus a simple configuration is sufficient.

  In the present invention, the constant speed setting unit 44 is not limited to the configuration of the rocker switch, and may be, for example, a rotary switch or a push switch.

  The outboard motor 10 of the present invention is suitable for use in various types of hull Si from small to relatively large.

1 is a side view of an outboard motor according to the present invention. It is a top view of the steering handle shown in FIG. 1 is a schematic system diagram of an outboard motor according to the present invention. It is a conceptual diagram which shows the concept by which the control part shown in FIG. 3 increases / decreases a target rotational speed. It is the figure which illustrated the display part shown in FIG. It is a control flowchart which shows an example of the throttle valve control performed by the control part shown by FIG. FIG. 4 is an operation explanatory diagram of the electronic governor and each unit shown in FIG. 3.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Outboard motor, 14 ... Engine, 18 ... Propeller, 41 ... Steering handle, 42 ... Grip, 43 ... Grip operation amount detection part, 44 ... Constant speed setting part (cruise switch, manual operation switch), 45 ... Display part , 51: control unit, 52: electric motor, 53: throttle valve, Nr: actual rotational speed, Ns: target rotational speed.

Claims (5)

In an outboard motor that electrically controls the opening and closing of the throttle valve so that the actual rotational speed of the engine that drives the propeller matches the target rotational speed,
A constant speed setting unit provided on the steering wheel and capable of manual operation;
A rotatable grip provided at the tip of the steering handle;
A grip operation amount detection unit for detecting the operation amount of the grip;
A control unit that sets the target rotation speed according to the operation amount detected by the grip operation amount detection unit and controls the opening and closing of the throttle valve so that the actual rotation speed matches the target rotation speed. And
The control unit is configured to control to maintain the target rotational speed at the time when the input is started when an electrical setting signal is input from the constant speed setting unit. Machine.   2. The outboard motor according to claim 1, wherein the control unit is configured to control to maintain the maintained target rotational speed as it is when the input of the setting signal is completed. .   When the operation amount changes after the setting signal is input, the control unit gradually changes the maintained target rotation speed from the maintained target rotation speed to a target rotation speed corresponding to the changed operation amount. The outboard motor according to claim 2, wherein the outboard motor is controlled to be   The outboard motor according to any one of claims 1 to 3, wherein the constant speed setting unit includes a manual operation switch disposed in the vicinity of the grip.   The outboard motor according to any one of claims 1 to 4, wherein the steering handle includes a display unit that displays the actual rotational speed and the target rotational speed.

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