JPS60237165A - Firing timing controller for engine - Google Patents

Abstract

PURPOSE:To adjust the setting position of firing timing detecting section around a crank shaft under low speed rotation by providing a temperature sensitive operating member for varying the condition with correspondance to the engine temperature variation. CONSTITUTION:A low speed side stopper 48 will limit the rotation of supporting base 15 and a pulser coil 16 around a crank shaft 11 to the lag angle side. Consequently, under low speed rotation where the engine is cooled, a temperature sensitive member 50 is at the contracted position of a drive rod 52 to bring a cam 53 into lowering position while to stop the low speed side stopper 48 at the position departed by the distance L1 from said rod 52 and to set a pulser coil 16 to the lead angle side thus to adjust the firing timing to further lead angle position. While under low speed rotation after warming of engine, said cam 53 will lift to bring the stopper 48 at the position separated by the distance L2 from said rod 52 (separated by the distance DELTAL to the lag angle side from aforementioned position) to set the pulser coil 16 at the lag angle detecting side thus to adjust the firing timing further to the lag angle side.

Description

[Detailed description of the invention] [Technical field] The present invention relates to an ignition timing control device for an engine.

[Background technology] In engines such as outboard motors, if the ignition timing is on the retarded side during low-speed operation such as idling or trolling under cold conditions, irregular combustion will occur and the driving feeling will be impaired, causing the engine to deteriorate. This may lead to suspension. In addition, during low-speed operations such as fitting and trolling after warming up, in order to improve the driving feeling, it is necessary to set the ignition timing to the retarded side to increase the intake ratio and improve combustion conditions. .

Conventionally, a device has been proposed that makes it possible to electrically perform desired ignition timing control according to changes in engine temperature. It is possible to control the timing at an appropriate time.

However, the above electrically controlled ignition timing control device has disadvantages in that it requires a power source and has a complicated structure.

[Object of the Invention] The present invention has a simple structure that automatically and reliably adjusts the ignition timing to the advanced side during low-speed operation in a cold state of the engine, and automatically adjusts the ignition timing to the advance side during low-speed operation after warming up. The purpose is to reliably adjust the angle to the retard side. [Structure of the Invention] One aspect of the present invention is that an ignition timing detection section is disposed around the crankshaft of an engine body, and an operating section for operating the detection section is disposed integrally with the crankshaft. An ignition timing control device for an engine, comprising a temperature-sensitive actuator whose state changes depending on a change in engine temperature, and a set position of the detection section around the crankshaft during low-speed operation can be adjusted by changing the state of the temperature-sensitive actuator, When the engine is running at low speed in a cold state, the detection section is set to the advance angle detection side, and when the engine is running at low speed after warming up, the detection section is set to the retard angle detection side.

[Detailed description of the invention] Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a side view showing a first embodiment in which the present invention is applied to an outboard motor engine, and FIG. 2 is a sectional view showing the main parts of the engine.

In P+, lO is an engine body, and a crankshaft 11 protrudes from the upper part of the engine body 10. The crankshaft 11 is arranged vertically, and the piston (not shown) moves horizontally. At the top of the engine body 10, two annular parts 12 and 13 are provided so as to double surround the crankshaft 11.
An oil seal 14 is installed between the inner annular portion 12 and the crankshaft 11. Reference numeral 15 denotes a support base, which supports a pulsar coil 16 serving as an ignition timing detection section for detecting ignition timing. The support stand 15 has an inner diameter slightly larger than the outer diameter of the inner annular portion 12 and an outer diameter slightly smaller than the inner diameter of the outer annular portion 13,
A part of the arm portion 17 projects in the radial direction. Further, the support stand 15 is formed with a plurality of leg portions that protrude upward. The support base 15 has an annular groove formed on its outer periphery, and a protrusion in the inner diameter direction of an annular adhesive retainer 8 having a T-shaped cross section is slidably engaged in the annular groove. The step part on the outer diameter side of the T-shaped cross section of this retainer 18 is engaged with the inner peripheral side edge part of the outer annular part 13, and the retainer 18 is attached to the engine body by a stopper 19 bent in a crank shape. It is fixed at 10. Therefore, this support stand 15
is rotatable relative to the engine body 10.

Next, magneto will be explained. A rotor 20 is formed into a substantially bowl-like shape with an open bottom, and a boss portion 21 at the center thereof is fixed to the crankshaft 11. That is, the boss part 2
The inner surface of crankshaft 11 and the protruding portion of crankshaft 11 are tapered, and both are key-coupled by a half-moon key 22 and firmly coupled by a nut 23 screwed onto the end of crankshaft 11. Permanent magnets 24 are fixed to the inner surface of the rotor 20 in the radial direction. Reference numeral 25 denotes a power generation coil, and a plurality of coils are arranged in a ring shape so as to correspond to the inner surface of the permanent magnet 24. These power generation coils 25 are fixed to a plurality of legs 26 protruding from the engine main body 10'.

27A and 27B are permanent magnets fixed to the outer peripheral surface of the boss portion 21 of the rotor 20. The pulsar coil 16
is fixed to the inner surface of the annular holder 28. Each of the permanent magnets 27A and 27B is an operating part that operates the pulsar coil 16, and each faces the pulsar coil 16 once during one rotation of the crankshaft 11, so that an electric pulsar is induced in the pulsar coil 16. The holder 28 is fixed to a leg 15A projecting from the support base 15. Therefore, the pulsar coil 16 rotates around the crank @11 together with the support base 15. This pulser coil 16 is
The ignition timing is detected from the rotation angle of the crankshaft 11, and by changing the position of this pulsar coil 16, the ignition timing can be changed.

As described above, the magneto is composed of the power generation coil 25 provided inside the rotor 20, the pulsar coil 16, and the permanent magnets 24, 27A, 27B, etc. facing these.

Next, the throttle operation mechanism 29 will be explained. Throttle operating lever 3 forming throttle operating mechanism 29
0 is rotatably attached to the engine body 10 by a port 31. One end of a throttle wire 32 is connected to the throttle operation lever 30 . On the other hand, each throttle valve 33 of each upper, middle, and lower carburetor 33A, 33B, 33C is connected to a lever 34A, 34B, 34C.
, are connected to each other by a link 35, and can be interlocked to have the same opening degree. 36 is a cam plate, and this cam plate 36 is rotatably supported by a port 37;
Its upper end is connected to the throttle operating lever 3 by a link 38.
Connected to 0. Above/<-34C is lower carburetor 3
It rotates together with the throttle valve 33 of 3C,
A cam follower 39 that abuts against the cam plate 36 is provided on this 8-34C. As a result, when the throttle operating lever 30 is rotated counterclockwise in FIG. 1 by the throttle wire 32, the cam plate 36 is rotated clockwise via the link 38, and the lever 34C is also rotated clockwise. Therefore, the throttle valve 33 of the lower carburetor 33C opens, and the links 35, levers 34A, 34
The throttle valves 33 of the respective carburetors 33A and 33B are also opened in conjunction with each other via B.

Next, the ignition advance angle operation mechanism 40 will be explained. An advance angle operation lever 42 forming the ignition advance operation mechanism 40 is rotatably attached to the engine main body IO coaxially with the throttle operation lever 30 by a port 31. Here, when the advance angle is operated /< -41, the rotation return correction in the counterclockwise direction is applied to the throttle operation lever 30 in FIG. 1 by a return spring (not shown), and the throttle operation lever 30 is Rotation in the counterclockwise direction in FIG. 1 is restricted by a formed stopper 7 (not shown). The advance angle control lever 41 is connected via a link 42 to an intermediate lever 44 that is rotatably supported by the engine body 10 by a port 43. The arm portion 17 of the support base 15 is connected to the tip of the intermediate lever 44 via a link 45. That is, when the throttle operating lever 30 rotates counterclockwise during the throttle opening operation, the advance operating lever 41 rotates together with the throttle operating lever 30, allowing the ignition timing to be advanced.

Here, the support stand 1 holding the above-mentioned pulser coil 16
As shown in FIG. 3, a low-speed side engaging portion 46 and a full-load side retaining portion 47 are provided at two positions in the circumferential direction on the outer circumferential portion of 5 to protrude radially outward. The low-speed side engagement portion 46 engages the low-speed side stopper 4, which will be described in detail later, during low-speed operation of the engine.
8 to restrict the rotation of the support base 15 in the retard direction, thereby making it possible to restrict the maximum advance angle of the ignition timing. Also,
The full load side engagement part 47 is connected to a full load side stopper 49 fixed to the engine main body lO during full load operation of the engine.
to restrict the rotation of the support base 15 in the advance direction,
The maximum advance angle of ignition timing can be regulated.

Therefore, in a portion of the engine body 10 that can effectively transmit temperature changes, for example, a portion close to the exhaust passage,
A temperature-sensitive actuating body 50 containing wax or the like is provided. The temperature-sensitive actuator 50 includes a drive rod 52 that is slidably supported by a support portion 51 formed in the engine body 10, expands when the temperature of the engine body 10 increases, and contracts when the temperature of the engine body 10 decreases. In addition, a cam 53 is provided at the tip of the drive rod 52. On the other hand, a driven rod 55 holding the low-speed stopper 48 is slidably supported by a support portion 54 formed in the engine body IO.

A cam follower 56 is provided at the end of the driven rod 55 opposite to the low speed stopper 48.
The cam follower 56 engages in a cam groove 57 carved in the cam 53.

That is, in this first embodiment, the temperature sensitive actuating body 50
a cam groove 57 of the cam 53 that moves up and down depending on the state change;
By engaging the driven port/end 55 with the cam follower 56,
By moving the low speed stopper 48, it is possible to restrict the rotation of the support base 15 and the pulsar coil 16 in the retard side direction around the crankshaft 11. As a result, when the engine is running at low speed in a cold state, as shown in Figure 2,
The drive rod 52 of the temperature-sensitive actuator 50 is in the retracted position, the cam 53 is placed in the lowered position, the low-speed side stopper 48 is stopped at a distance 11LI from the drive rod 52, and the low-speed side retaining portion of the support base 15 is closed. 46 and ia (1111) The pulsar coil 16 is set to the advanced angle detection side by the collision with the stopper 48, and the ignition timing during this low-speed operation can be adjusted to the advanced angle side.On the other hand, after the engine warms up, During low-speed operation, as shown in FIG. The pulser coil 16 is set to the retard detection side by the collision between the low speed side retaining part 46 of the support base 15 and the low speed side stopper 48. The ignition timing during operation can be adjusted to a more retarded side.

The cam groove 57 provided in the cam 53 has a certain degree of curved portion on each of the cold engine side and the warm-up side, so that the driven rod 55 is provided with a certain degree of curved portion on each of the cold engine side and the warm engine side.
It is necessary to maintain the low-speed side stopper 48 in a stable state at each of the set position on the advance angle detection side and the set position on the retard angle detection side without moving it. In addition, the cam groove 5 of the cam 53
By appropriately selecting the shape of the groove in the intermediate portion between the cold side and the warm-up side in step 7, the ignition timing can be appropriately set in the temperature state of the engine body or in the transition period from the cold state to the warm-up state. is possible.

Next, the operation of the first embodiment will be explained.

During low-speed operation in a cold engine state, the engine body 10 is in a low-temperature state, so the low-speed side stopper 48 remains at a distance L1 from the drive rod 52 before engine cranking, and the pulsar coil 1
6 is set on the advance angle detection side. This allows the engine's ignition timing to be adjusted more advanced, which stabilizes the combustion state and improves driving feeling.

On the other hand, during low-speed operation after warming up the engine, the engine body 1
0 changes to a high temperature state, the temperature sensitive actuator 50 expands, the low speed side stopper 48 moves to a position a distance L2 from the drive rod 52, and the pulser coil 16 is set to the retard detection side. As a result, the ignition timing of the engine is adjusted to be more retarded, the combustion state is stabilized, and the driving feeling can be improved.

That is, according to the first embodiment, with a simple structure, the ignition timing is automatically and reliably adjusted to the advanced side during low-speed operation when the engine is cold, and the ignition timing is adjusted to the advanced side during low-speed operation after warming up. To automatically and reliably adjust to the retard side.

FIG. 5 is a side view showing the main parts of the second embodiment of the present invention, and FIG.
The figure is a sectional view taken along the line Vl--Vl in FIG. 5.

In this second embodiment, the link 42 of the first embodiment is formed by a temperature-sensitive link 60 made of a shape memory alloy. , 61 are fixed to the engine body 10 and in contact with the temperature-sensitive link 60, and are connected to the engine body lO
This is a heat transfer body made of a steel plate that can transmit temperature changes to the temperature-sensitive link 60.

That is, the temperature-sensitive link 60 expands and contracts due to temperature changes in the engine body 10, and the support base 1 during low-speed operation.
5 and the pulsar coil 16 around the crankshaft 11 can be adjusted. When the engine is running at low speed under a cold state, the temperature-sensing link 60 contracts as shown in FIG. Adjustable to the side. On the other hand, during low-speed operation after warming up the engine, the temperature-sensitive link 60 is extended and the pulsar coil 16 is set to the retard detection side, making it possible to adjust the ignition timing to a more retarded side during this low-speed operation.

Therefore, also in the case of the second embodiment, the ignition timing is automatically and reliably adjusted to the advance side during low-speed operation in a cold state of the engine, and the ignition timing is adjusted to the advanced side during low-speed operation after warm-up due to the simple structure. can be automatically and reliably adjusted to the retarded side.

In each of the above embodiments, the present invention is applied to an engine equipped with an ignition advance control device $40 that allows the pulsar coil 16 to be moved by moving the support stand 15. However, in the present invention, the Flamag base is fixed to the crankshaft, and the basic ignition timing is controlled by the relative position of the pulsar coil integrated into the Flamag base and the magnet fixed to the flywheel rotating around the crankshaft. In an ignition timing control device that can electrically control ignition timing based on the engine rotational speed that is determined and electrically detected, a temperature-sensitive actuator whose state changes depending on engine temperature changes the flag, base, or pulser coil. The ignition timing may be controlled by rotating the ignition timing.

Furthermore, in each of the above embodiments, a case has been described in which the pulser coil is used as the detection part and the magnet is used as the actuation part. However, in the present invention, the ignition timing control device uses a point fixed to the Flamag base as the detection part, a cam that rotates integrally with the crankshaft as the actuation part, and can determine the ignition timing by opening and closing the points by the cam. is also applicable, and in that case, the set position of the flame mag base or point around the crankshaft during low-speed operation will be adjusted depending on the state change of the temperature-sensitive operating body.

[Effects of the Invention] As described above, the present invention has a detection section for one ignition timing arranged around the crankshaft of the engine body, and an operating section for operating the detection section arranged so as to be integrated with the crankshaft. An ignition timing control device for an engine comprising a temperature-sensitive actuator whose state changes with changes in engine temperature, and adjusts the set position of the detection section around the crankshaft during low-speed operation according to changes in the state of the temperature-sensor actuator. When the engine is running at low speed when the engine is cold, the detection section is set to the advance angle detection side, and when the engine is running at low speed after warming up, the detection section is set to the retardation detection side. . Therefore, with a simple structure, the ignition timing is automatically and reliably adjusted to the advanced side during low-speed operation when the engine is cold, and the ignition timing is automatically and reliably adjusted to the advanced side when the engine is running at low speeds after warming up. It becomes possible to automatically and reliably adjust the ignition timing to the retarded side at the time of rotation.

[Brief explanation of drawings]

Fig. 1 is a side view showing an outboard engine to which the first embodiment of the present invention is applied, Fig. 2 is a sectional view showing the main parts of the engine, and Fig. 3 is ignition timing control of the engine. FIG. 4 is a side view showing the setting state of the low-speed stopper by the temperature-sensitive actuating body of the same engine, and FIG. 5 is a schematic view of the engine to which the second embodiment of the present invention is applied. FIG. 6 is a sectional view taken along the line vr-vr in FIG. 5. 10... Engine body, 11... Crankshaft, 15
...Support stand, 16...Pulsa coil, 27A, 27
B...Permanent magnet, 46...Low speed side engaging portion, 48...
・Low speed side stopper, 50...Temperature-sensitive actuating body, 6o...
Temperature-sensitive link. Agent Patent Attorney Osamu Shiokawa

Claims (1)

[Claims] (1) An ignition timing control device for an engine in which an ignition timing detection section is disposed around the crankshaft of the engine body, and an operating section for operating the detection section is disposed integrally with the crankshaft, Equipped with a temperature-sensitive actuator whose state changes according to engine temperature changes, the setting position of the detection section around the crankshaft during low-speed operation can be adjusted by changing the state of the temperature-sensitive actuator, and when the engine is running at low speeds when the engine is cold. An ignition timing control device for an engine, characterized in that the detecting section is sometimes set to the advance angle detecting side, and the detecting section is set to the retarded angle detecting side when the engine is running at low speed after warming up.