JP3312404B2 - Starting device for fuel injection type two-stroke engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a starter for a fuel injection type two-stroke engine, and more particularly to a starter for selecting an appropriate one of a recoil type starter and an electric type starter. The present invention relates to a fuel injection type two-stroke engine starting device that controls the amount of fuel injected by an injector so as to meet the above-mentioned conditions, thereby improving the startability.

[0002]

2. Description of the Related Art A two-stroke engine is an engine in which a piston moves in two strokes by one rotation of a crankshaft. The two-stroke engine is distinguished from a four-stroke engine. Outboard motor,
And it is mounted on snowmobiles called snowmobiles.

[0003] As a starting device of the fuel injection type two-stroke engine, there is one disclosed in Japanese Patent Application Laid-Open No. 3-172552. The two-cycle engine start-time injection amount control device disclosed in this publication is configured to consider a correction coefficient value according to a cranking time so that the fuel injection amount does not become rich at the time of restart. To improve startability.

[0004]

By the way, in a conventional fuel injection type two-stroke engine starting device, the fuel injection amount at the time of starting is set to match the recoil type starter.

[0005] As a result, if the cranking time is long during the starting operation by the electric starter, the air-fuel ratio becomes rich, there is a possibility that the starting cannot be performed, and there is a disadvantage that the usability is poor.

Further, when the battery voltage is low at the time of starting operation by the electric starter, the cranking torque is low, and there is a disadvantage that an appropriate air-fuel ratio becomes rich before reaching the combustion chamber of the engine.

[0007] Furthermore, when the temperature is extremely low or when the battery voltage is low, there is no one having a function of selecting which of the recoil type starter or the electric type starter is better and informing the driver of the starter. There is no control of the fuel injection amount from the injector to meet the above, and improvement has been desired.

[0008]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a fuel injection type two-stroke engine provided with an injector for injecting fuel and provided with a recoil starter and an electric starter in order to eliminate the above-mentioned disadvantages.
A cooling water temperature sensor for detecting a cooling water temperature is provided, and at the time of starting the engine, a detection signal from the cooling water temperature sensor and a battery voltage signal of a battery are inputted, and one of the recoil starter and the electric starter is input. A control unit is provided to select and notify an appropriate starter and to control the fuel injection amount of the injector so as to match the selected starter.

[0009]

According to the invention as described above, when the engine is started, the detection signal from the cooling water temperature sensor and the battery voltage signal of the battery are input to the control unit, and the control unit controls the recoil starter and the electric starter. In addition to selecting an appropriate starter and notifying the starter, the fuel injection amount of the injector is controlled so as to match the selected starter, thereby improving the startability.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

1 to 7 show an embodiment of the present invention. 2 (a) and 2 (b), reference numeral 2 denotes a snowmobile,
Is a steering ski, 6 is a hood, 8 is an engine, 10 is a windshield, 12 is a steering wheel, 14 is a seat, 1
6 is a track.

The snowmobile 2 is configured to reduce the snow contact pressure by increasing the weight, to increase the output per unit weight, to run through fresh snow and deep snow, and to be small and lightweight. In addition, a two-cycle engine 8 that is easy to start in cold weather is mounted.

The snowmobile 2 is, as shown in FIG.
An intake passage 20 communicating with the combustion chamber 18 of the engine 8 is provided, and the intake passage 20 is formed in a throttle body 24 that connects an air box 22 on the upstream side.

Further, an intake air temperature sensor 26 for detecting an intake air temperature is provided in the air box 22, and a throttle valve 28 is provided in the throttle body 24.
A throttle position sensor 30 for detecting the throttle opening of the throttle valve 28 is provided.

A plurality of injectors 32 are provided above the throttle body 24 to inject fuel into each cylinder (not shown). A fuel tank 36 is connected to the injectors 32 via a fuel supply passage 34. In addition, the fuel return passage 38 is also connected.

In the middle of the fuel supply passage 34,
A fuel pump 40 for feeding the fuel under pressure is provided, and the position of the fuel pump 40 may be a broken line in FIG.

In the fuel return passage 38, an excess fuel pressure is applied to the fuel tank 36 to adjust the fuel injection pressure to a predetermined value.
A pressure regulator 42 which escapes to the side is provided.

The snowmobile 2 is provided with a control unit 44. The control unit 44 includes a crankshaft 46 of the engine 8.
Angle sensor 5 for detecting a crank position and an engine speed by a flywheel magneto 48 attached to the
0, a cylinder discriminating sensor 52 for discriminating a cylinder coming to the next top dead center (TDC), and the throttle position sensor 3
0 and a water pump 54 disposed on the engine 8
For example, various sensors such as a cooling water temperature sensor 58 provided at a portion of the water bypass passage 56 to detect a cooling water temperature, an atmospheric pressure sensor 60 built in the control unit 44 and detecting the atmospheric pressure, and the intake air temperature sensor 26 are provided. In addition to being connected, a battery 62 and an ignition switch 64 for supplying an operation power supply and detecting a power supply voltage are connected.

When the engine 8 is started, the control unit 44 receives the detection signal from the cooling water temperature sensor 56 and the battery voltage signal of the battery 62, and receives signals from the two starters, a recoil starter and an electric starter. It is configured to select and notify one of the appropriate starters and to control the fuel injection amount of the injector 32 so as to match the selected starter.

As shown in FIG. 3, the control unit 44 includes:
A CDI unit 66, an AC regulator 68, a headlamp 70, and a warning lamp 72 are connected to each other.

Reference numeral 74 denotes an ignition coil, 76
Is an ignition plug, 78 is an EFI relay for an ignition OFF circuit,
80 is a DC RR, 82 is a dropping register, 84
Is a fuel pump relay, 86 is an EFI relay, 88 is a fuseable link, and 90 is a charge lamp.

Next, the function of the control unit 44 will be described with reference to FIG.

When a detection signal is input from the crank angle sensor 50 and the cylinder discrimination sensor 52 to the control unit 44, the CDI pulse crank position and the engine speed are calculated (100) from the detection signal, and the cylinder discrimination pulse is calculated. The cylinder discrimination setting (102) is performed by.

From the calculation of the CDI pulse crank position and the engine speed (100), the total injection amount is set (1).
04), and drive setting (106) of the injectors 32 is performed by the total injection amount setting processing (104) and the cylinder determination setting processing (102).
To output a drive signal to the controller.

The throttle position sensor 3
The basic fuel injection amount is set (110) based on the detection signal from 0, the CDI pulse crank position, the calculation of the engine speed (100), and the basic fuel injection amount map (108), and the engine speed is set (112). Later, it is communicated to the setting processing (104) of the total injection amount.

The cooling water temperature sensor 58 and the atmospheric pressure sensor 6
0, and an increase correction coefficient in each sensor is set (114) according to each detection signal of the intake air temperature sensor 26.
Only the detection signal from the cooling water temperature sensor 58 is output to the setting of the engine driving method (116), and is output to the alarm lamp 72.

The correction fuel injection amount is calculated (118) based on the output signal from the increase correction coefficient setting process (114) and the output signal from the basic fuel injection amount setting process (110) in each sensor.

When the detection signal of the power supply voltage of the battery 62 is input, the voltage correction of the injector 32 is increased (120), and the correction fuel injection amount is calculated (11).
8) and the output signal from the voltage correction increase processing (120). 1> NO. NO. Calculation of fuel injection amount (TiLN) (122) and NO. 2 Calculation of fuel injection amount (TE) (124).

After performing the battery voltage determination setting (126), the detection signal of the power supply voltage of the battery 62 is output to the engine driving method setting (116) described later.

Further, when a detection signal is input from the ignition switch 64, the engine-driven recoil starter (128) and the electric, that is, electric starter (130) are selected, and the recoil starter (128) is selected. NO. 1 Calculation of fuel injection amount (Ti
LN) (122) and NO. 2 Calculation of fuel injection amount (T
E) NO. From (124). 1 or NO. 2 The fuel injection amount is compared (132) and output to the above-mentioned setting of the engine speed (112).

After the selection of the electric starter (128), NO. Calculation of one corrected fuel injection amount (134) is performed,
This is output to the above-mentioned setting of the engine speed (112).

When the engine 8 is started, the control unit 44 receives the detection signal from the cooling water temperature sensor 56 and the battery voltage signal of the battery 62, and receives signals from the two starters, a recoil starter and an electric starter. When one of the appropriate starters is selected and the alarm lamp 72 is notified, the selected starter, for example, when the electric starter is selected, the electric starter is smaller than the fuel injection amount of the recoil starter. The fuel injection amount is controlled to match.

Next, the operation will be described with reference to the flowchart for starting control of the two-cycle engine shown in FIG.

When the fuel injection control program is started, it is determined (200) whether or not the engine is started, that is, whether or not the ignition switch 64 is started.
00) is YES, the ignition switch 64
It is determined which of the specification of the recoil starter and electric, that is, the electric starter, based on the presence or absence of the output signal of the turn position signal to the control unit 44 (202).

If the above determination (200) is NO, the normal total injection amount (Ti) control (204) is calculated, and the process proceeds to return (RETURN) (222).

Further, in the determination (202), when it is determined that the recoil starter is appropriate, the starting injection amount (TiLTNK) is obtained from the map shown in FIG. (20
6).

Then, a rotation correction coefficient (KLN) is obtained from the map shown in FIG. 5B based on the detection signal of the engine speed (208), and a time correction is performed from the map shown in FIG. A coefficient (KLT) is determined (210).

Further, the fuel injection amount at the time of starting by the recoil starter is calculated based on the formula TiLN1 = TiLNTK × KLN × KLT TiLN1: starting injection pulse width TiLTNK: starting basic injection amount, starting basic pulse width Control is performed (212).

If the electric starter is judged to be appropriate in the above judgment (202), the starting injection amount (TiLTNK) is obtained from the map shown in FIG. (214).

Then, a rotation correction coefficient (KLN1) is obtained (216) from the map of FIG. 5D based on the detection signal of the engine speed (216), and time correction is performed from the map of FIG. Coefficient (KLT)
(218).

Further, the fuel injection amount at the time of starting by the electric starter is calculated based on the following equation: TiLN2 = TiLNTK × KLN1 × KLT TiLN2: Starting injection pulse width TiLTNK: Starting basic injection amount, Starting basic pulse width Control is performed (220).

At this time, the fuel injection amount at the start by the electric starter is calculated to be smaller than the fuel injection amount at the start by the recoil starter.

After calculating and controlling the fuel injection amount at the time of starting by the recoil starter (212), and calculating and controlling the fuel injection amount at the time of starting by the electric starter (22).
After (0), the process proceeds to RETURN (222).

Referring to FIG. 6, after setting (300) of the total injection amount at start (TiLN), NO.
Calculation of one fuel injection amount (302) and setting of a correction coefficient (60)
4) is performed, and output to drive the injector 32 (306).

The rotation fluctuation between the recoil starter and the electric starter will be described with reference to FIGS. 7A and 7B. In the recoil starter, when the number of times of drawing is one, the rotation fluctuation is as shown in FIG. The state shown in (a) is reached, and the control of the fuel injection amount during that period ends.

An optimum air-fuel ratio (A / F) that reaches the fuel chamber 18 until the engine is completely detonated by this repetition is ensured, and an appropriate fuel injection amount is set with the minimum number of pulls. I have.

Further, in the electric starter, the rotational fluctuation is in a state as shown in FIG.
It is clear that the air-fuel ratio becomes rich with the same amount of fuel injection as the recoil starter, and it is a good measure to set and control the amount of fuel injection to be small.

Next, the notification operation by the alarm lamp 72 will be described.

In FIG. 4, the battery voltage determination setting (1
After performing 26), the motor is driven by the electric starter, and it is determined whether or not the engine speed is such that an optimum air-fuel ratio reaching the combustion chamber 18 is obtained. Then, it is determined whether or not the electric starter is possible based on the detection signal from the cooling water temperature sensor 58. If it is impossible to determine both the engine speed and the cooling water temperature, the alarm lamp 72 uses the recoil type. Notify the driver that the starter is properly used.

Thus, when the engine 8 is started, the detection signal from the cooling water temperature sensor 58 and the battery 6
The control unit 44 which inputs the battery voltage signal of No. 2 can select either the recoil type starter or the electric type starter, and notify the starter by using the alarm lamp 72. A defect can be avoided reliably, and startability can be improved, which is practically advantageous.

When the starting operation is performed by a proper starter notified by the alarm lamp 72, the control unit 44 controls the fuel injection amount of the injector 32 so as to match the selected starter. In addition, the air-fuel ratio is not enriched, the starting failure due to the air-fuel ratio enrichment can be reliably avoided, the usability can be improved, and the emission of unburned gas can be reduced. It can be improved and is economically advantageous.

[0052]

As described above in detail, according to the present invention, in a fuel injection type two-cycle engine provided with a recoil type starter and an electric type starter, a cooling water temperature sensor for detecting a cooling water temperature is provided to start the engine. In this case, the detection signal from the cooling water temperature sensor and the battery voltage signal of the battery are input, and the appropriate starter of either the recoil type starter or the electric type starter is selected and notified, and in order to match the selected starter. Since the control unit that controls the fuel injection amount of the injector is provided, the starting operation can be reliably performed, the starting failure can be reliably avoided, the startability can be improved, and the selected starter can be improved. The air-fuel ratio is not enriched by the control unit that controls the fuel injection amount to match, And obtained reliably avoid the dynamic defect and give improved usability, yet be obtained by improving the fuel economy, economically advantageous.

[Brief description of the drawings]

FIG. 1 is a flowchart for starting control of a two-stroke engine according to an embodiment of the present invention.

FIG. 2A is a right side view of a snowmobile in a partially cut-away state. (B) It is a right view of a snowmobile.

FIG. 3 is a schematic view of a starting device of a two-cycle engine.

FIG. 4 is a block diagram illustrating an operation of a control unit.

FIG. 5 (a) is a diagram showing a relationship between a starting basic injection amount (TiLTNK) and a cooling water temperature (Tw). (B) Rotation correction coefficient (KLN) and engine speed (N)
FIG. (C) is a diagram illustrating a relationship between a time correction coefficient (KLT) and a cranking time (T). (D) is a diagram showing the relationship between the rotation correction coefficient (KLN1) and the engine speed (N).

FIG. 6 is a flowchart showing the setting of a starting total injection amount.

FIG. 7A is a diagram showing rotation fluctuation in a recoil starter. FIG. 3B is a diagram illustrating rotation fluctuation in the electric starter.

[Explanation of symbols]

 Reference Signs List 2 snowmobile 4 steering ski 6 hood 8 engine 10 windshield 12 handle 14 seat 16 truck 20 intake passage 24 throttle body 26 intake temperature sensor 28 throttle valve 30 throttle position sensor 32 injector 36 fuel tank 40 fuel pump 44 control unit 50 crank Angle sensor 52 Cylinder discrimination sensor 54 Water pump 58 Cooling water temperature sensor 60 Atmospheric pressure sensor 62 Battery 64 Ignition switch 72 Warning lamp for notification

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F02N 11/08 F02N 11/00 F02N 3/02 F02D 41/06 330

Claims (1)

(57) [Claims] 1. A fuel injection type two-stroke engine provided with an injector for injecting fuel and having a recoil starter and an electric starter, a cooling water temperature sensor for detecting a cooling water temperature is provided. Receives a detection signal from a cooling water temperature sensor and a battery voltage signal of a battery, selects and notifies an appropriate one of the recoil starter and the electric starter, and notifies the injector to match the selected starter. A starting device for a fuel injection type two-stroke engine, comprising a control unit for controlling a fuel injection amount of the fuel injection type.