JP4002557B2 - Engine with fuel injection device - Google Patents

Description

The present invention relates to an engine having a fuel injection device is disposed in an intake passage connecting the intake port and the air cleaner of the engine.

  Conventionally, a fuel injection engine with a mechanical governor in which a fuel injection device is incorporated in an engine with a mechanical governor in the fuel injection engine has been created. This has the advantage that an optimal engine operating state that cannot be obtained with a carburetor engine with a mechanical governor can be obtained while effectively suppressing the cost increase by making the governor mechanical. For example, an engine disclosed in Patent Document 1 is known.

As described above, in the means for combining the mechanical governor and the fuel injection device, the engine speed at idling is set to the lowest possible value in order to reduce noise and fuel consumption. This is because the fuel injection control can be performed, so that it is possible to meet an appropriate A / F (theoretical air fuel consumption) even at an extremely low speed range as compared with an engine of a carburetor specification.
JP-A-11-93750

  However, immediately after starting at a low temperature such as in winter, the idle rotation is lowered as much as possible, so that the influence of mechanical loss and engine oil viscosity cannot be ignored, and an unexpected rotation drop may occur. There is a concern that such a large rotation drop may cause inconveniences such as unstable idle rotation and unstable response such as stalling the engine or not being able to catch up with the increase in speed.

  The conventional mechanical governor has a recovery function when the throttle valve is fully closed in the extremely low speed range controlled by the fuel injection device and the engine speed falls below the prescribed idle speed due to the above-mentioned factors. There is a face that cannot catch up, and it is necessary to take some measures.

An object of the present invention is to provide a stable idling state and acceleration with good response by preventing unexpected rotation drop in an idling state so as to be suitable for a fuel injection engine equipped with a mechanical governor. Thus, an engine including a fuel injection device that improves engine startability at a low temperature is provided.

The configuration of claim 1 is an engine including a fuel injection device (21) interposed in an intake path (Q) of the engine (E) as shown in FIG.
As shown in FIG. 1, a fuel injector (21) includes an intake passage communicating the intake path and the air cleaner side of the intake passage of the intake port side and (22) ejecting body (10A) is formed (10), A throttle valve (42) that can open and close the intake passage (10A), and a fuel injection means (15) that injects downstream of the throttle passage (42) in the intake passage (10A) in the intake flow direction. Consisting of
As shown in FIG. 7A, a bypass path (45) for short-circuiting the upstream side and the downstream side in the intake flow direction with respect to the throttle valve (42) in the intake path (10A) is provided. 45) is equipped with a switching valve (46) that can be opened and closed ,
The direction of the cylinder center axis (5) is the vertical direction, the installation direction of the crankshaft (30) is the front-rear direction, and the width direction of the cylinder head (20) is the horizontal direction,
As shown in FIG. 4, an intake distribution case (24) constituting an intake path on the intake port side is attached to a lateral surface of the cylinder head (20), and intake air is distributed to a plurality of cylinders by the intake distribution case (24). In this way, a mounting seat (25) that is inclined horizontally is provided at the rear portion of the intake distribution case (24), and the fuel injection device (21) is mounted on the mounting seat (25), and is inclined horizontally from the rear portion of the intake distribution case (24). The fuel injection device (21)
As shown in FIG. 1, a butterfly type is formed at the central portion in the width direction of the oblique intake air passage (10 </ b> A) in the injection body (10) when viewed from directly above the injection body (10) of the fuel injection device (21). The valve shaft (42b) of the throttle valve (42) is arranged, and as shown in FIG. 7 (a), the valve shaft (42b) of the throttle valve (42) is directed in the vertical direction so that the fuel injection device (21) In providing the fuel injection means (15) and the outlet (45c) of the bypass passage (45) in the injection body (10),
As shown in FIG. 1, when the injection body (10) of the fuel injection device (21) is viewed from directly above, it is downstream of the valve shaft (42b) of the throttle valve (42) in the same manner as this valve shaft (42b). The fuel injection means (15) is arranged at the center in the width direction of the intake passage (10A), and as shown in FIG. 7 (a), the outlet (45c) of the bypass passage (45) is directly below the fuel injection means (15). ).

According to a second aspect of the present invention , in the engine including the fuel injection device according to the first aspect, the bypass passage (45) is formed in the injection body (10) with a perforation, and the switching valve (46) includes: A valve body that can be switched and moved between an action position that closes across the bypass path (45) by protruding movement and a non-action position that retreats and opens from the bypass path (45) when retracted. 46a) and a solenoid (46B) supported by the injection body (10) and capable of extending and retracting the valve body (46a).

According to a third aspect of the present invention , in the engine equipped with the fuel injection device according to the first or second aspect, the switching valve (46) is detected by a temperature detecting means (29) for detecting the temperature of the engine (E). The switching valve (46) and the temperature detection means (so as to open the bypass passage (45) when the temperature is lower than a predetermined temperature and close the bypass passage (45) when the temperature exceeds the predetermined temperature). 29) is equipped with a control means (48) for linking with (29).

According to a fourth aspect of the present invention , in the engine including the fuel injection device according to any one of the first to third aspects, the engine (E) is equipped with a mechanical governor (12), and the mechanical governor ( 12), the throttle valve (42) is opened and closed.

According to the first aspect of the present invention, if the switching valve is operated to open the bypass passage, the intake air amount can be increased regardless of the opening degree of the throttle valve. Therefore, if the bypass path is opened when the engine is in an idling state at a low temperature start, the engine speed can be forcibly increased. Therefore, the cause of the rotation drop due to the increase in mechanical loss due to the low temperature and the increase in engine oil viscosity is covered ( In addition, the idling rotation state is stabilized, the response is improved even when the vehicle is accelerated in a state where sufficient warm-up operation is not performed, and the risk of unexpected engine stall is also eliminated.

As a result, an idle-up mechanism has been added that prevents unexpected rotation drops in the idle rotation state, provides a stable idle operation state even at low temperature start, and improves engine acceleration at low temperatures. Therefore, the engine provided with the fuel injection device that can control the operation of the engine with high accuracy can be provided as one having more excellent overall performance.

According to the configuration of the second aspect, since the bypass passage is formed in the injection body itself and the switching valve is also supported by the injection body, high functionality is achieved with an idle-up mechanism, and the whole is compact. An engine including a fuel injection device that can be configured as described above can be provided.

According to the configuration of claim 3, the control means automatically controls the engine so that the bypass path is opened when the engine temperature is lower than the predetermined temperature, that is, when the engine temperature is low, and closed when the engine temperature exceeds the predetermined temperature. The Therefore, the effect of the configuration of claim 1 is an engine including a convenient fuel injection device that can be obtained automatically without performing a special operation.

According to the configuration of the fourth aspect, the engine speed, which is a disadvantage of the engine with a mechanical governor frequently used in agricultural machinery and industrial machines, is improved in stability at an extremely low speed, and is suitable for an engine with a mechanical governor at a low cost. An engine including a fuel injection device can be provided.

Hereinafter, a case where an engine having an embodiment of a fuel injection device according to the present invention is applied to a vertical three-cylinder fuel injection gasoline engine will be described with reference to the drawings. 2, the direction of the cylinder center axis 5 is the vertical direction, the head cover 6 side is up, the cylinder block 7 side is down, the crankshaft 30 is installed in the front-rear direction, the cooling fan 50 side is front, and the flywheel 16 side is Later, it is defined that the width direction of the cylinder head 20 is the horizontal direction.

As shown in FIG. 1, the engine E has the cylinder head 20 assembled to the upper part of the cylinder block 7, the head cover 6 is assembled to the upper part of the cylinder head 20 as shown in FIG. The flywheel 16 is assembled to the rear part of the cylinder block 7. As shown in FIGS. 1 and 2, this engine comprises a fuel injection device 21 as a fuel metering device 1, which is the fuel injection system 21 to control metering in mechanical governor 12. The fuel injection device 21 injects fuel (gasoline) into the intake passage, and can be mixed with air and supplied to the intake ports 3a to 3c.

The arrangement and schematic configuration of the fuel injection device 21 are as follows.
As shown in FIG. 1, an intake distribution case 24 serving as an intake distribution means 4 is attached to the lateral surface of the cylinder head 20. This intake distribution case 24 is for distributing intake air to a plurality of cylinders, and is not a structure in which a branch pipe is branched from a parent pipe like an intake manifold, but a box facing an intake port opening of a cylinder head 20. It has a mold structure. An oblique lateral mounting seat 25 is provided at the rear portion of the intake distribution case 24, the fuel injection device 21 is attached to the mounting seat 25, and the fuel injection device 21 protrudes obliquely laterally from the rear portion of the intake distribution case 24. The fuel injection device 21 includes a throttle input arm 17.

The configuration of the mechanical governor 12 is as follows.
As shown in FIG. 2, the governor lever 14 of the mechanical governor 12 is disposed in front of the intake distribution case 24. That is, the governor lever 14 is disposed on the side of the gear case 23. Further, a governing lever 18 and a governor spring 19 of the mechanical governor 12 are arranged in front of the fuel injection device 21, and the governing lever 18 is attached to a lateral wall of the intake distribution case 24. The upper limit of the high speed setting of the governing lever 18 is limited by the high speed limiting bolt 26, and the lower limit of the low speed setting is limited by the low speed limiting bolt 27.

The governor lever 14 is linked to the governing lever 18 via a governor spring 19 in an interlocking manner. The governor lever 14 receives a governor force from a governor weight in the gear case 23. The governor lever 14 swings due to an unbalanced force between the governor force and the spring force of the governor spring 19. As shown in FIG. 1 , the governor lever 14 and the throttle input arm 17 of the fuel injection device 21 are interlocked and connected by an output rod 13 as viewed from above. As a result, the throttle valve 42 provided in the fuel injection device 21 to open and close the intake pipe (intake path) 22 is operated by the mechanical governor 12, and the fuel injection operation is performed according to the throttle opening. A fuel injection control device A for performing

As shown in FIGS. 1 to 3, the intake ports 3 a to 3 c of the first to third cylinders (cylinders) Cy <b> 1 to Cy (see FIG. 5) are connected to each other on the head lateral surface 2 of the cylinder head 20 of the engine E. A box-shaped intake distribution case 24 is attached and fixed to the head lateral surface 2 in a state of opening in parallel and covering these intake ports 3a to 3c. As shown in FIG. 4, the side surface 24a on the cylinder head 2 side of the box-shaped intake distribution case 24 is largely open, and the intake air diversion chamber 8 which is a single space in the intake distribution case 24 is opened from the open side surface 24a. The intake ports 3a to 3c communicate with each other. A thick mounting seat 25 for mounting the fuel injection device 21 is formed obliquely laterally outward in a plan view on the wall of the rear end side of the intake distribution case 24 that is largely biased toward the first cylinder. Yes. The attachment seat 25 is formed with a perforation for the intake inlet 9.

As shown in FIG. 1, the fuel injection device 21 is formed in the injection body 10 with an injection body 10 having one end bolted to an attachment seat 25 of an intake distribution case 24 via an insulator (spacer) 49. and a fuel injection means 15 for injecting the fuel or the like into the intake passage 10A. A mounting seat for the fuel injection means 15 is formed on the upper surface of the injection body 10 formed of a square block, and an input arm 17 of a throttle valve 42 mounted on the injection body 10 is pivotally supported. . The injection body 10 has the same mounting dimensions and shape as the carburetor in the case of the carburetor specification, and the fuel injection device 21 and the carburetor are configured to be interchangeable with each other. The other end of the injection body 10 and the intake pipe 22 extending from the air cleaner 11 are connected in communication via a reduction block 43. A reduction hose 44 of blow-by gas extending from the head cover 6 is connected to the reduction block 43.

More specifically, as shown in FIG. 7, the fuel injection device 21 includes an injection body 10 having an intake passage 10 </ b> A that connects the intake passage on the intake port side and the intake passage on the air cleaner side, and an intake passage 10 </ b> A. The throttle valve 42 can be opened and closed, and the fuel injection means 15 that injects the throttle valve 42 disposed in the intake passage 10A downstream of the valve body 42a in the intake flow direction. The injection body 10 is formed with a bypass passage 45 that short-circuits the upstream side and the downstream side in the intake flow direction with respect to the throttle valve 42 in the intake passage 10A, and a switching valve 46 that can switch the bypass passage 45 intermittently. The idle-up mechanism I is configured by an ECU 28, a water temperature sensor 29, and the like which will be described later.
The arrangement of each element of the fuel injection device 21 is as follows.
As shown in FIG. 1, when the injection body 10 of the fuel injection device 21 is viewed from directly above, the valve shaft 42 b of the butterfly throttle valve 42 is provided at the center in the width direction of the obliquely lateral intake passage 10 </ b> A in the injection body 10. As shown in FIG. 7A, the valve shaft 42b of the throttle valve 42 is directed in the vertical direction, and the fuel injection means 15 and the outlet 45c of the bypass passage 45 are provided in the injection body 10 of the fuel injection device 21. As shown in FIG. 1, when viewed from directly above the injection body 10 of the fuel injection device 21, the center of the intake passage 10A in the width direction is located downstream of the valve shaft 42b of the throttle valve 42 in the same manner as the valve shaft 42b. The fuel injection means 15 is disposed in the section, and the outlet 45c of the bypass passage 45 is disposed directly below the fuel injection means 15 as shown in FIG.

As shown in FIG. 7 (a), the bypass passage 45 includes a lateral path 45a that opens in the vicinity of the intake passage 10A on the end face 10a on the reduction block 43 side, and an intake passage 10A that communicates with the lateral path 45a. It is formed in a curved path composed of a vertical path 45b communicating with the outside, and a switching valve 46 is provided in a state of plugging the outside of the vertical path 45b. The longitudinal path 45 b is formed with a tapered taper path portion 47 that communicates portions having different diameters, and the taper path portion 47 is controlled to be opened and closed by the switching valve 46.

  As shown in FIGS. 7A and 8, the switching valve 46 includes a piston rod 46A having a truncated conical valve body 46a at the tip thereof and a solenoid 46B for extending and retracting the piston rod 46A. The injection body 10 is equipped with a plug. If the piston rod 46A is extended, the valve body 46a closes the taper path portion 47 (see the phantom line in FIG. 8), the bypass path 45 is cut off, and if the piston rod 46A is shortened, the valve body 46a is tapered. Retreating from the path portion 47, the bypass path 45 is opened. In other words, the non-acting position h in which the valve body 46a is protruded and shut off across the bypass path 45 and the operating position s in which the valve body 46a is retracted and retracted from the bypass path 45 to open are switchable. A solenoid 46B is provided in the injection body 10. Further, the switching valve 46 may be configured to be a power saving type in which the piston rod 46A is urged to return to the non-operating position where the piston rod 46A is extended by a spring or the like, and the piston rod 46A is driven to be shortened against the urging force only when energized. good.

With this configuration, as shown in FIG. 4, the fuel and intake air from the fuel injection device 21 flow from the intake inlet 9 in a state where the fuel and intake air are directed to substantially the center position between the first intake port 3 a and the second intake port 3 b. The gas is discharged into the chamber 8 and thereafter supplied to the intake ports 3a to 3c, and the mixed gas of the injected fuel and the intake air is divided into three types of routes r1 to r3 by the intake ports 3a to 3c. The intake distribution case 24 has an intake branch chamber 8 that is an internal space formed as a single space, and is smaller in size than a structure in which an independent intake path is formed for each of the intake ports 3a to 3c. In addition, there is an advantage that the structure is simplified. As shown in FIGS. 1 and 2, reference numeral 11 a denotes a suction portion of the air cleaner 11.

As shown in FIGS. 5 and 6, the fuel injection control device A includes a signal circuit a and a control circuit b related to an ECU (an example of control means) 28, and a fuel circuit c. The signal circuit a includes a water temperature sensor 29 provided in the cooling water passage 7a of the cylinder block 7, a non-contact type crank sensor (an example of a rotational speed detection means) 31 that detects the rotational speed of the crankshaft 30 per unit time, An intake air temperature sensor 32 that detects the internal temperature of the air cleaner 11 and an intake air pressure sensor 33 that detects the internal pressure of the intake pipe 22 that connects the air cleaner 11 and the fuel injection device 21 are connected to the ECU 28. Yes.

The control circuit b is configured by connecting an ECU 28 with a fuel pump 35, a fuel injection unit 15 , and an ignition coil 37 that applies a high voltage to the spark plug 36. The fuel circuit c is configured by providing a fuel hose 38 for supplying the fuel in the fuel tank 34 to the fuel injection means 15 by the fuel pump 35. The fuel pump 35 is configured as an electromagnetic drive type in which a pressure regulator (pressure regulator) 35a and a filter 35b are integrally provided.

The ECU 28 stores an injection amount control map created for each of the first to third cylinders Cy1 to Cy3, and each cylinder Cy1 to Cy3 has a dedicated injection amount control for each cylinder. It is controlled so that the amount of fuel according to the map is injected. As a control input, the intake pressure and the engine speed, that is, the crank sensor 31 and the intake pressure sensor 33 are used to control the fuel injection amount. More specifically, a fuel injection amount map for each of the first to third cylinders Cy1 to Cy3 using the intake pressure and the engine speed as gains is created in advance and stored in the ECU 28. Control for driving the fuel injection means 15 is performed so that the fuel injection amount is adjusted and set based on detection information from the intake pressure sensor 33.

That is, the storage means 39 for storing the characteristic condition of the fuel injection amount created for each of the plurality of cylinders Cy1 to Cy3, and the cylinder detection means for detecting which cylinder of the plurality of cylinders Cy1 to Cy3 should be supplied with fuel. 40, and the ECU 28, when a cylinder to be supplied with fuel is detected, the cylinder detecting means 40 and the storage means so that the fuel injection operation is performed based on the characteristic condition prepared for the detected cylinder. 39 and the fuel injection means 15 are linked. The characteristic condition stored in the storage means 39 provided in the ECU 28 is map data based on a combination of the intake pressure and the engine speed per unit time. This map data is created for each of the cylinders Cy1 to Cy3. It is remembered. When detection information of both the intake pressure sensor 33 and the crank sensor 31 is output, data closest to the detection information in the map data is selected, and the fuel injection means 15 is based on the selected data. The ECU 28 functions so as to actuate.

Next, the idle-up mechanism I that operates at a low temperature will be described. The switching operation of the switching valve 46 provided in the fuel injection device 21 is controlled by idle control means 48 provided in the ECU 28. That is, when the detected temperature of the water temperature sensor (an example of temperature detecting means) 29 is a low temperature equal to or lower than the predetermined temperature, the water temperature sensor 29 is shortened to open the bypass 45 (see FIG. 8), and the detected temperature of the water temperature sensor 29 exceeds the predetermined temperature. The idling control means 48 links the water temperature sensor 29 and the switching valve 46 so that the bypass path 45 is shut off (see the phantom line in FIG. 8).

When the intake air amount increases, the detection value of the intake pressure sensor 33 increases, and as a result, the fuel injection amount by the fuel injection means 15 also increases, and the engine speed (idle speed) increases accordingly. For example, the switching valve 46 can be configured to be variable so that the passage cross-sectional area of the bypass passage 45 can be variably adjusted so that the idle up amount (rotation speed) can be variably adjusted.

In the idle operation state immediately after the engine is started, as shown in FIG. 7B, the throttle valve 42 is in a fully closed state in which the throttle valve body 42a is inscribed in the intake passage 10A, and the fuel injection device 21 is provided. As a result, the engine idles at a lower rotational speed than in the case of the carburetor specification. However, in cold environments such as cold areas in winter, the viscosity of the engine oil is higher, which increases mechanical loss, so it is difficult to stabilize idling immediately after starting by rotating and dropping. When the acceleration operation such as suddenly moving the governor lever in the state and increasing the rotation speed, the response is dull for a relatively long time, such as misfiring and stalling without following the sudden increase in intake gas. May appear.

However, by the addition of the idle-up mechanism I described above, when a predetermined temperature below the low temperature, since control for increasing than the set value the idle speed by opening the bypass passage 45 by an idle control means 48 is performed, the engine Even if there is an increase in the viscosity of the oil and an accompanying increase in mechanical loss, stable idling can be performed at a somewhat higher rotational speed. In addition, if the rapid acceleration operation is performed in this state, since the idling is higher, the response can be improved such that the engine speed can be rapidly increased without stalling as in the prior art.

  The cylinder detecting means 40 is configured as follows. As shown in FIG. 5, the rotor 41 mounted on the crankshaft 30 so as to rotate integrally is formed with a plurality of sensing projections on the outer periphery, for example, 120 degrees centering on the axis of the crankshaft 30. First to third protrusions t1 to t3 are formed at intervals, and only the third protrusion t3 is set to have a long circumference. The first protrusion t1 takes the ignition timing of the first cylinder Cy1 by the sensing operation of the crank sensor 31 that detects a change in magnetic force accompanying the passage of the first protrusion t1, and similarly, the second and third protrusions t2, 3 are respectively This is for taking the ignition timing of the second and third cylinders Cy2 and Cy3.

  That is, as shown in FIG. 5, when the rotor 41 rotates in the direction of arrow A, when the rotor 41 rotates about 240 degrees from the passage of the first protrusion t1, the second protrusion t2 is encountered by the crank sensor 31, and The third protrusion t3 is encountered when rotated about 240 degrees. Since the length of the third protrusion t3 is long, the reaction time with the crank sensor 31 becomes long, whereby the ECU 28 can recognize that the third protrusion t3 has been detected, and the passage detection of the third protrusion t3. Thus, it is possible to recognize that the crankshaft 30 has made one revolution, and it is also possible to recognize the engine speed per unit time by measuring the time until the next passage detection.

  Furthermore, the first protrusion t1 and the second protrusion t2 are made the same by storing the reaction order of the crank sensor 31 with the first and second protrusions t1 and t2 after passing through the third protrusion t3. In addition, the first and second protrusions t1 and t2 can be individually detected. Therefore, the cylinder 41 is constituted by the rotor 41 having these three protrusions t1 to t3 and the crank sensor 31.

  As another configuration of the cylinder detection means 40, the three protrusions t1 to t3 are all formed with different circumferential lengths, or the circumferential length is the same and the axial length is changed, or different metal materials are provided. For example, various devices on the rotor 41 side can be considered. Further, a structure in which the crank sensor 31 is used as a camshaft sensor that operates in cooperation with a camshaft transmitted by reducing the rotation of the crankshaft to ½ is also possible.

Further, among the first to third cylinders Cy1 to Cy3, the injection amount increases in the order of the first cylinder Cy1 closest to the fuel injection device 21, the second cylinder Cy2 closest to the next, and the third cylinder Cy3 furthest away. In other words, the injection amount is set to increase as the distance from the fuel injection device 21 of the intake ports 3a to 3c increases. As a result, the same amount of fuel is supplied to any of the cylinders Cy1 to Cy3, and control is performed so as to obtain the same combustion state as much as possible. The difference in the injection amount may be stored in the storage device 39 so as to obtain an optimum condition by performing an operation test of the engine E in advance and to be added to the map data. In addition, you may add the process which makes an injection timing earlier for the cylinder farther from the fuel-injection apparatus 21 to the process which changes this injection quantity.

Incidentally, the water temperature sensor 29 is an input information source for idling up at a low temperature, and is a sensor that can be used as a means for detecting an overheating state such as overheating after warming up. Also, if the environmental temperature varies depending on the season such as summer and winter and the place of use (lowland, highland ), the air density varies accordingly, and the mixing ratio with the fuel also changes. An intake air temperature sensor 32 is provided.

  As described above, in the engine E with the mechanical governor 12 provided with the fuel injection device 21 with the idle-up mechanism I according to the present invention, i. Enables extremely low idle speed, ii. No variation in idle rotation even when the engine is cold, iii. The effect that the acceleration performance immediately after the low temperature start is stabilized can be obtained.

Top view of fuel injection engine Side view showing the top of the engine of FIG. Top view of intake distribution case Schematic showing the progress of intake air in the intake distribution case Control system diagram showing the configuration of the fuel injection control device Block diagram showing details of control by ECU (A) is a longitudinal sectional view showing the structure of the fuel injection device (b) is a plan view of the main part showing the attitude of the throttle valve body when fully closed Enlarged view showing the switching valve for the bypass

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Injection body 10A Intake passage 12 Mechanical governor 15 Fuel injection means 22 Air cleaner side intake path 24 Intake port side intake path 29 Temperature detection means 42 Throttle valve 45 Bypass path 46 Switching valve 46a Valve body 46B Solenoid 48 Control means A Fuel injection Control device E Engine Q Air intake path

Claims (4)

An engine including a fuel injection device (21) interposed in an intake path (Q) of the engine (E),
Fuel injection system (21) includes an intake passage communicating the intake path and the air cleaner side of the intake passage of the intake port side and (22) ejecting body (10A) is formed (10), said intake passage (10A) A throttle valve (42) that can be opened and closed, and fuel injection means (15) that injects downstream of the throttle valve (42) in the intake passage (10A) in the intake flow direction.
A bypass passage (45) for short-circuiting the upstream side and the downstream side in the intake flow direction with respect to the throttle valve (42) in the intake passage (10A) is provided, and the bypass passage (45) is a switching valve that can be switched open and closed ( 46) it is equipped,
The direction of the cylinder center axis (5) is the vertical direction, the installation direction of the crankshaft (30) is the front-rear direction, and the width direction of the cylinder head (20) is the horizontal direction,
An intake distribution case (24) constituting an intake path on the intake port side is attached to a lateral surface of the cylinder head (20), and intake air is distributed to a plurality of cylinders by the intake distribution case (24). 24) An oblique lateral mounting seat (25) is provided at the rear portion, and a fuel injection device (21) is attached to the mounting seat (25), and the fuel injection device (21) obliquely lateral from the rear portion of the intake distribution case (24). Project
When the injection body (10) of the fuel injection device (21) is viewed from directly above, the valve of the butterfly throttle valve (42) is disposed at the center in the width direction of the obliquely-inspired intake passage (10A) in the injection body (10). A shaft (42b) is arranged, and the valve shaft (42b) of the throttle valve (42) is directed in the vertical direction so that the fuel injection means (15) and the bypass passage (45 ) Outlet (45c)
When the injection body (10) of the fuel injection device (21) is viewed from directly above, downstream of the valve shaft (42b) of the throttle valve (42), similarly to the valve shaft (42b), the intake passage (10A) An engine equipped with a fuel injection device, characterized in that a fuel injection means (15) is arranged at the center in the width direction, and an outlet (45c) of a bypass passage (45) is arranged directly below the fuel injection means (15). . An engine comprising the fuel injection device according to claim 1,
The bypass passage (45) is perforated in the injection body (10), and the switching valve (46) is projected and moved to close across the bypass passage (45), and retracted. The valve body (46a) that can be switched to a non-operating position that retreats and opens from the bypass path (45) by being moved, and the valve body (46a) that is supported by the injection body (10) is expanded and contracted. An engine provided with a fuel injection device, characterized by comprising a solenoid (46B) that is movable . An engine comprising the fuel injection device according to claim 1 or 2,
The switching valve (46) opens the bypass passage (45) when the detected temperature of the temperature detecting means (29) for detecting the temperature of the engine (E) is equal to or lower than a predetermined temperature, and exceeds the predetermined temperature. The fuel injection system is characterized by being equipped with control means (48) for linking the switching valve (46) and the temperature detection means (29) so as to close the bypass passage (45). Engine with equipment. In the engine provided with the fuel injection device according to any one of claims 1 to 3,
Wherein and engine mechanical governor (E) (12) is equipped, the said throttle valve by a mechanical governor (12) (42) is configured in a state of being opened and closed, fuel injection device according to claim With an engine .

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