JPH0318659A - Starter for vehicle with fuel injection type engine - Google Patents

Abstract

PURPOSE:To improve startability without increasing battery capacity by force- feeding fuel from an human driven auxiliary fuel pump prior to engine start up, thus raising fuel pressure. CONSTITUTION:The fuel pump 54 of a motorcycle is driven by a cable 58, and a roller 54d rolls together with a rotor 54c so as to suck fuel from a suction port 54f and discharge it to an outflow port 54h. An auxiliary fuel pump 110 is of a plunger type and driven by interlocking a plunger 11 with the kick crank 112 of a kick starter. The fuel is sucked into a pressurized room 118 by the reset of the kick crank 112 and discharged onto the ouflow port 54h side of the fuel pump by stepping-in. As the specified fuel pressure can be thus obtained by the stepping-in of the kick crank at the time of engine start-up, startability can be improved without increasing battery capacity.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention provides a starting method for use in a vehicle equipped with a fuel-injected engine that pumps fuel to a fuel injection valve by a fuel pump mechanically driven by the engine. This is related to equipment. (Background of the Invention) Fuel injection engines are known in which fuel such as gasoline is injected into intake air and ignited by a spark plug. Automobiles and other vehicles equipped with this type of engine usually use an electric fuel pump to pump fuel to the fuel injection valves. On the other hand, in small vehicles such as motorcycles, the battery capacity installed in the vehicle is generally small. Therefore, it is being considered that the fuel pump can be mechanically driven by the engine itself, reducing the burden on the battery. But in this case,
When starting the engine, it is necessary to operate the starter motor or kick starter for a long time to wait for the fuel pressure in the fuel pump to rise sufficiently. This not only results in poor startability but also requires a large battery with a large capacity.

(Object of the Invention) The present invention was made in view of the above circumstances, and it is an object of the present invention to improve the startability of the engine when the fuel pump mechanically driven by the engine pumps fuel to the fuel injection valve. Another object of the present invention is to provide a starting device for a vehicle equipped with a fuel injection engine that can avoid increasing the size of the battery.

(Structure of the Invention) According to the present invention, the object is to provide a vehicle with a fuel injection type engine that pumps fuel to a fuel injection valve by a fuel pump mechanically driven by the engine, which includes an auxiliary fuel pump driven by human power. This is achieved by a starting device for a vehicle with a fuel injection type engine, characterized in that fuel can be pumped from the auxiliary fuel pump to the fuel injection valve prior to starting the engine.

(Embodiment) Fig. 1 is a conceptual diagram of an embodiment of the present invention, Fig. 2 is a side view of a motorcycle equipped with the same, and Fig. 3 is a sectional view of a fuel pump, etc. In FIG. 2, reference numeral 10 is a frame, 12 is a rear arm, 14 is a rear wheel, l6 is a front fork, 18 is a front wheel, and 20 is a front fork.
22 is a steering wheel, 22 is a fuel tank, 24 is a driver's seat, 25 is a battery, 26 is a fairing, and 28 is a rear body cover.

The rear arm 12 is connected to the lower end of the cushion unit 34 by links 30 and 32. A downward return habit is given to l2.

Reference numeral 36 is a two-stroke, two-cylinder engine with preloaded crank chamber, consisting of a front cylinder 38 and an upper cylinder 40, which form a substantially L-shape when viewed from the side.
and have ■. The crankcase 42 has each type M38, 4
0 crank chambers 44 and 46 (FIG. 1) are formed independently. 48 is a crankshaft, and this crankshaft 48
Each piston is connected to the piston by a connecting rod.

52 (52a, 52b) are exhaust pipes (Fig. 2),
The exhaust pipe 52a extends from the lower surface of the front cylinder 38 to the crankcase 4.
It passes below 2 and extends to the right of 14. In addition, the exhaust pipe 52b is connected to the rear surface of the upper cylinder 40 by the body cover 28.
It passes through the interior and extends above the port 14. 54 is a mechanically driven fuel pump attached to an engine mounting bracket (not shown), and is driven by the engine 36 via a round gear mechanism 56 provided on the left side of the crankcase 42 and a flexible cable 58. It will be done. That is, this fuel pump 54 is driven by the crankshaft 48 and a shaft that is constantly rotated by the crankshaft 48. Since the fuel pump 54 is rotatably driven by a flexible cable 58, the fuel pump 54 can be placed away from the high temperature part of the engine 36 and placed in a position where it is easily exposed to steering wind, or placed in a position where there is less engine vibration. can do.
Therefore, it is not adversely affected by engine heat or vibration. This pump 54 is composed of a roller pump as shown in FIG. In FIG. 3, the shaft 54a is driven by a cable 58 via a one-way clutch 54b. Along with the rotor 54c fixed to this shaft 54a, the roller 54
cl is transferred within the rotor housing 54e. Due to this transfer of the roller 54d, fuel is sucked in from the suction port 54f and is discharged to the outlet port 54h via the one-way valve 54g. 59 is a pressure accumulator, which connects a fuel chamber 59c defined by a free piston 59b in the cylinder 59a to the outlet 54h side of the fuel pump 54, and connects this piston 59b from the pressurizing chamber 59d side with a spring (see Fig. 1). ) or gas pressure (Figure 3). This pressure accumulator 59 is the piston 5
The movement of 9b absorbs the pulsation of fuel pressure on the side of the outlet 54h, and also generates fuel pressure while the engine is stopped to improve engine startability. 60 (60a, 60b) are shutter type throttle valves. Both throttle valves 60 are made almost symmetrically,
Each is connected to the crankcase 42 by a rubber joint 62 (62a, 62b) with a reed valve in between. Throttle body 64 of each throttle valve 60 (
64a, 64b) are fitted with valve plates 66 (66a, 64b) from above.
6b) is attached to be able to be raised and lowered, and each valve plate 66 is connected to the wires, levers 70 (70a, 70b), and links 72 (72a, 72b) by rotating a throttle grip (not shown) provided on the steering handle 20. It is lifted and lowered through. The opening degree θ of the throttle valve 60 is detected by a potentiometer 74 provided on the right throttle valve 60b. Each throttle body 64 is equipped with an electromagnetic fuel injection valve 76 (76a, 76b), which injects fuel obliquely toward the intake air flow direction from near the lower edge of the valve plate 66. These fuel injection valves 76 are of a so-called bottom-feed type, in which fuel is supplied from the side toward the injection port side of the electromagnetic coil. Fuel is fed under pressure from the fuel pump 54 to the fuel injection valves 76 on both sides. 80 (80a, 80b) is a fuel pressure regulator, which adjusts the fuel pressure fed from the fuel pump 54 to the injection valve 76 to a predetermined pressure determined by the intake negative pressure of each cylinder 38, 40. When the fuel pressure exceeds this predetermined pressure, a portion of the fuel is recirculated to the fuel tank 22. This regulator 80 includes a diaphragm 82 (82a,
82b), an intake negative pressure chamber 84 (84a, 84b) i3 defined by this diaphragm 82, and a fuel pressure chamber 86
(86a, 86b). The fuel pressure of the injection valve 76 is introduced into the fuel pressure chamber 86 . A return force toward the fuel pressure chamber 86 is applied to the diaphragm 82 by a compression spring 88 (88a, 88b). Further, the guyaflame 82 has fuel pressure adjustment nozzles 90 (90a, 9
0b) are opposed to each other, and the diaphragm 82 serves as a flapper that approaches and separates from this nozzle 90, forming a known flapper-nozzle type pressure adjustment mechanism. Therefore, when the fuel pressure increases beyond a predetermined level, the pressure in the fuel pressure chamber 86 increases, and the diaphragm 82 compresses the spring 88 and is displaced, opening the nozzle 90. Since the intake negative pressure is guided to the negative pressure chamber 84, when the intake negative pressure increases, the fuel pressure at which the nozzle 90 starts to open becomes lower. Therefore, at low load and high speed, the injection amount is reduced by shortening the opening time of the fuel injection valve 76 and lowering the fuel pressure. In this way, the tire flam 82 compresses the spring 88 and the nozzle 9
0, the fuel in the fuel pressure chamber 86 flows through this nozzle 90.
The fuel is then returned to the fuel tank 22. 92 (92a, 92
b) is a pressure detector that detects the internal pressure of the crank chambers 44, 46, and is attached to the frame 10 above the engine 36 via a rubber tamper 94 (FIG. 2). These pressure detectors 92 are communicated with the left and right outer surfaces of the crankcase 42 through vibrators 96 (96a, 96b), detect the internal pressure of the crank chambers 44, 46, and output electric signals Pa, pb corresponding to this internal pressure. ．． Note that air check valves 98 (98a, 98b) are attached to each of the pipes 96 (FIG. 1). These allow only outside air to flow into the pipe 96, and the pressure sensor 92 is connected to the crank chambers 44, 4.
Prevent the air-fuel mixture in 6 from flowing in. 100 (Fig. 1) is the rotational speed N of the crankshaft 48 and the ignition timing signal α
This is a rotation speed detector that detects the rotation speed. 104 (FIG. 2) is a control device composed of a microcomputer, and a wall 106 is installed at the rear of the fuel tank 22.
It is housed in a space defined by This control device 104 has the above-mentioned throttle opening θ, crank chamber pressure p. , pl, , rotational speed N, ignition timing signal α, and other signals are input. It may also be controlled by inputting various signals such as engine temperature T, engine acceleration/deceleration, engine brake, etc. The control device 104 determines the optimal fuel injection amount corresponding to the operating state based on these various input signals, determines the injection time for this injection amount, and controls the fuel injection valve 76.
Open the valve. Here, the control device 104 has a built-in memory, and stores characteristics of the optimum injection amount in this memory in advance.
Determine the injection amount and determine the injection time. Based on this injection time, injection is performed intermittently once or multiple times during one rotation of the crankshaft in synchronization with the rotation of the crankshaft.

Next, the auxiliary fuel pump 110 will be explained. This pump 11
0 is a known plunger type pump, which is driven by a kick crank 112 of a kick starter. That is, the plunger 114 of the pump 110 sucks fuel into the pressurizing chamber 118 via the one-way valve 116 in conjunction with the return of the kick crank 112, and sucks the fuel in the pressurizing chamber 118 in conjunction with the depression of the kick crank 112. The fuel is discharged through the one-way valve 120 to the outlet 54h of the fuel pump 54. Therefore, in this embodiment, when the kick crank 112 is depressed when starting the engine, the auxiliary fuel pump 110 sends fuel to the fuel injection valve 76 and pressure accumulator 59 to obtain a predetermined fuel pressure. On the other hand, by depressing the kick crank 112, the crankshaft 48 also rotates, making it possible to start the engine.

In addition, if it is possible to increase the injection amount automatically or with a manual switch installed on the vehicle's steering wheel, etc. at the time of starting,
Startability is further improved.

In this embodiment, the auxiliary fuel pump 110 is linked to a kick starter, but the present invention may be configured with another manual or foot-operated pump independent of the kick starter or the electric starter motor. In this case, if the engine is started while maintaining the fuel pressure raised by the auxiliary fuel pump by utilizing the elasticity of the pressure accumulator 59 and the vibrator itself, the startability will be improved more reliably. (Effects of the Invention) As described above, the present invention provides an auxiliary fuel pump that is manually driven, and pumps fuel from the auxiliary fuel pump to the fuel injection valve prior to starting the engine. The fuel pressure can be increased to enable fuel injection before the fuel pump starts pumping fuel. This improves engine startability. Additionally, since this auxiliary fuel pump is manually driven, there is no need to increase battery capacity.

[Brief explanation of drawings]

Fig. 1 is a conceptual diagram of an embodiment of the present invention, Fig. 2 is a side view of a motorcycle equipped with the same, and Fig. 3 is a sectional view of a fuel pump. 36...Engine, 54...Fuel pump, 76...Fuel injection valve, l10...Auxiliary fuel pump.

Claims (1)

[Scope of Claims] A vehicle with a fuel injection type engine in which a fuel pump mechanically driven by the engine pumps fuel to a fuel injection valve, comprising an auxiliary fuel pump driven by human power, A starting device for a vehicle with a fuel injection type engine, characterized in that fuel can be pumped from a lever auxiliary fuel pump to a fuel injection valve.