JPS6231649Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a gasoline engine, and particularly to an intake control mechanism for facilitating the starting of a gasoline engine.

As a conventional gasoline engine, for example, the 1970 nine
“Internal Combustion Engine Design/Structure Drawing Collection” (Sankaido) published in March
The one listed on page 38 of the book is known. To explain the structure of this gasoline engine, 1 is a cylinder block in which a cylinder hole 2 is formed, and the cylinder hole 2 is connected to the cylinder block 1.
It is closed by a cylinder head 3 fixed to the upper end of the cylinder. A piston 4 is slidably housed in the cylinder hole 2, and the piston 4 is connected to a crankshaft 6 via a connecting rod 5. A flywheel 7 is connected to the crankshaft 6, and a ring gear 8 is attached to the outer periphery of the flywheel 7.
is fixed. A starter motor 9 with a predetermined output is fixed to the cylinder block 1, and the starter motor 9 is connected to a battery (not shown) via a starter switch. The starter motor 9 has a pinion gear 10 that can mesh with the ring gear 8, and the pinion gear 10 meshes with the ring gear 8 when the starter switch is turned on.

The aforementioned cylinder hole 2 communicates with the carburetor 11 via an intake passage provided with an intake port and a throttle valve (not shown).

In such a conventional gasoline engine, the starter motor 9 is driven at the time of startup, and its rotation is converted into sliding motion of the piston 4 via the ring gear 8, flywheel 7, crankshaft 6, and connecting rod 5. Due to this sliding movement of the piston 4, the air-fuel mixture drawn into the cylinder hole 2 from the carburetor 11 through the intake passage and the intake port is compressed and ignited, and the gasoline engine is started.

Generally, in such a conventional gasoline engine, even when the throttle valve is in the idling position, the descending speed of the piston 4 at the time of starting is slow, so a large amount of air-fuel mixture is sucked in and a large force is required to compress it. I needed it. As a result, in conventional internal combustion engines, the predetermined output of the starter motor 9 must be set to a large value in order to apply a large force to the piston 4, which consumes a large amount of battery power and Since the weight of the starter motor 9 also increases, there are problems in that the starting performance of a vehicle equipped with such a gasoline engine deteriorates, and at the same time, the fuel consumption rate also deteriorates. In particular, when a gasoline engine is equipped with a flywheel device for starting the engine as disclosed in Japanese Patent Application Laid-Open No. 49-51428, the mass of the flywheel must also increase the output of the starter motor 9. The problem arises that it must be made larger for the same reason.

This invention was made by focusing on these problems, and includes a throttle means in the intake passage near the intake port of a gasoline engine, a means for determining the engine operating state, and a means for determining the engine operating state, and the throttle means is only activated when the engine is cranking. It is an object of the present invention to solve the above-mentioned problems by providing a control means for switching the throttle means to the open position when the throttle position is in operation.

This invention will be explained below based on the drawings.

FIG. 2 is a diagram showing the first embodiment of this invention. First, the configuration will be explained. 14 is a cylinder hole 1.
5, the upper end of the cylinder hole 15 is closed by a cylinder head 16. Cylinder hole 15
A piston 17 is slidably housed in the housing, and the piston 17 is connected to a crankshaft (not shown) via a connecting rod 18. Similar to conventional gasoline engines, a flywheel and a starter motor of a predetermined capacity are connected or connectable to this crankshaft, but a description thereof will be omitted for the sake of brevity. The cylinder head 16 is formed with an intake port 19 and an exhaust port 20 that open into the cylinder hole 15, and these intake ports 19 and exhaust ports 20 are connected to an intake valve 21.
It can be opened and closed by an exhaust valve 22. The intake port 19 communicates with the air cleaner 25 via an intake passage 24 formed in the intake manifold 23, and is connected to the intake passage 2 on the downstream side of the air cleaner 25.
4 is provided with a known carburetor 26 and a throttle valve 27. A throttle valve 28 as a throttle means is provided for each cylinder in the intake passage 24 between the throttle valve 27 and the intake valve 21 of each cylinder hole 15, as close as possible to the intake valve 21. These throttle valves 28 are connected to each intake port 20 (preferably the intake valve 21).
It is desirable that the throttle valve 28 be provided in the intake passage 24 as close as possible to the throttle valve 28, and a notch 29 is provided in a portion of the throttle valve 28, as shown in FIG. Each throttle valve 28 is connected by a shaft 30 as shown in detail in FIG. An actuator 33 is connected to this shaft 30 via a link 31 and a rod 32, and this actuator 33 is connected to a cylinder 35 in which a port 34 is formed, and a cylinder 35 in which a port 34 is formed, as shown in detail in FIG. Piston 36 slidably housed
and a spring 37 that urges the piston 36 toward the port 34 side. Actuator 33
The port 34 communicates with an engine oil pump (not shown), and the piston 36 slides against the spring 37 when pressure oil is supplied from the oil pump, and the throttle valve 28 controls the flow of the air-fuel mixture. Switches to the nearly parallel fully open position. On the other hand, when the supply of pressure oil from the oil pump is stopped, the spring 3
7 moves the piston 36 toward the port 34, and the throttle valve 28 switches to the throttle position where it closes the intake passage 24, leaving a slight gap. Since this switching is performed based on the generation of oil pressure by the oil pump, in this embodiment, the oil pump has the function of determining the engine operating state. The aforementioned shaft 30 is connected to one end of a spring 38 as shown in FIG. 6, and the other end of the spring 38 is connected to a case 39 fixed to the intake manifold 23.
is connected to. The aforementioned shaft 30, link 31, rod 32, actuator 33, spring 3
8, the case 39, and the oil pump (not shown) constitute a control means 40 as a whole.

Next, the effect will be explained. When cranking to start a stopped gasoline engine, first turn on the starter switch to drive the starter motor. As a result, the piston 17 descends within the cylinder hole 15 and sucks the air-fuel mixture into the cylinder hole 15. At this time, the engine oil pump is not generating pressure oil, so the throttle valve 28 is in the throttle position. Therefore, even if the downward speed of the piston 17 is small, the amount of air-fuel mixture sucked into the cylinder hole 15 is smaller than in the past. Therefore, piston 1
7 rises and compresses the air-fuel mixture, and a starter motor with a small predetermined output can be used, so the power consumption of the battery can be reduced. At this time, since the throttle valve 28 is provided as close as possible to the intake valve 21, the amount of air-fuel mixture sucked into the cylinder hole 15 can be suppressed to a small volume, and the force required for compression can be made as small as possible. It can be done. Furthermore, since the weight of the starter motor is reduced, it is possible to improve the starting performance of a vehicle equipped with such a gasoline engine, and at the same time, to improve the fuel consumption rate. Furthermore, even when an engine starting flywheel as disclosed in Japanese Patent Laid-open No. 49-51428 is attached to a gasoline engine, the mass of the flywheel can be reduced and the fuel efficiency of the vehicle can be improved. Next, when the engine is in operation, the pressure oil supplied from the oil pump presses the piston 36 against the spring 37, so the throttle valve 28 is switched to the fully open position, and the throttle valve 28 is switched to the fully open position, similar to a conventional gasoline engine. The speed can be changed by a valve 27.

FIG. 7 shows a second embodiment of this invention, and the configuration will be explained first. 42 is an intake manifold of the gasoline engine, and an intake passage 43 within the intake manifold 42 communicates with the intake port of each cylinder hole. An intake pipe 44 is fixed to the intake manifold 43, and an intake passage 45 formed in the intake pipe 44 communicates the intake passage 43 with the atmosphere. A butterfly valve 46 is rotatably supported in the intake pipe 44, and the butterfly valve 46 is intended to reduce the blowback noise to the intake pipe 44 that is generated when the exhaust brake is activated, and also serves as a throttle means in the present invention. It also plays the role of The butterfly valve 46 is connected to an actuator 49 via a rod 47 and a link 48, and the actuator 49 communicates with an outlet port 51 of an electromagnetic switching valve 50. This electromagnetic switching valve 50 has an outlet port 51
In addition, an inlet port 52 and an atmospheric port 53 are formed which communicate with a negative pressure source, for example, a brake bath pump (not shown), and an electromagnetic switching valve 50
A spool 55 in which a passage 54 is formed is slidably housed in the spool 55 . The spool 55 is always urged toward the inlet port 52 by a spring 56, and when the solenoid 57 is energized, the spool 55 moves from the first position where the outlet port 51 and the atmosphere port 53 communicate with each other. to the second position communicating with. The solenoid 57 is connected to the battery 5 via a relay 58 having normally open contacts.
9 and the solenoid 6 of the relay 58.
0 is connected to the battery 59 via a switch 61. The switch 61 is turned ON or OFF by the signal from the comparator 62, and the comparator 62 compares the voltage signal from the engine rotation speed sensor 63 with the reference voltage signal from the reference voltage signal generator 64. It outputs a signal that turns on the switch 61 only when the voltage signal is greater than the reference voltage signal. Note that the voltage value of the reference voltage signal matches the value of the voltage signal output from the sensor 63 when the engine speed is, for example, 300 rpm. The aforementioned rod 47, link 48, actuator 49, switching valve 50, relay 58 and switch 61 constitute a control means 65 as a whole. Further, in this embodiment, the rotation speed sensor 63, the reference voltage signal generator 64, and the comparator 62 have a function as a driving state determining means.

Next, the effect will be explained. When the gasoline engine is stopped, the voltage signal from the rotational speed sensor 63 is "0", so the switch 61 is turned off and the contacts of the relay 58 are opened. As a result, solenoid 57 is demagnetized and spool 55 is in a first position communicating atmospheric port 53 and outlet port 51. Therefore, the actuator 49 maintains the butterfly valve 46 in a position where the valve 46 closes the intake passage 45 with a small gap remaining. When starting in this condition, the amount of air sucked into the cylinder hole decreases, as in the case of the gasoline engine described above, so less force is required to compress the air, and the starter motor outputs less than before. A small one is fine. Therefore, not only the power consumption of the starter motor is reduced, but also the weight of the starter motor is reduced, which improves the startability of a vehicle equipped with such a gasoline engine, and at the same time improves the fuel consumption rate.
Further, even when a flywheel device for engine starting is attached, the flywheel can be made to have a small mass. However, if this continues, the amount of intake air will decrease, making it difficult for the compression temperature to rise, and it is conceivable that starting performance will deteriorate. Therefore, when the rotational speed increases, the amount of intake air is increased. Therefore, when the engine speed becomes relatively large and sufficient for starting, the voltage value of the voltage signal output from the engine speed sensor 63 becomes higher than the voltage value of the reference voltage signal, and the signal from the comparator 62 causes the switch to be activated. 61 is turned on. As a result, the contacts of the relay 58 are closed, and the solenoid 57 of the electromagnetic switching valve 50 is closed.
is excited. Therefore, the inlet port 52 and the outlet port 51 communicate with each other, and the actuator 49 switches the butterfly valve 46 to a position where the valve 46 is substantially parallel to the flow of air in the intake passage 45. Therefore, a large amount of air can be sucked in, the compression temperature increases, and starting becomes possible.

Note that, instead of the butterfly valve 46, a throttle valve may be provided for each intake port, and an ignition mechanism may be provided to compensate for a decrease in compression temperature due to a decrease in the amount of intake air.

As explained above, according to this invention, a gasoline engine is provided with a cylinder hole, an intake port opening into the cylinder hole, and an intake passage communicating with the intake port. In addition, since the starter motor is provided with a means for determining the engine operating state and a control means for switching the throttle means to the throttle position only when the engine is cranking and to the open position when the engine is running, the starter motor can be made smaller. In addition, even if a flywheel device for engine starting is installed, the flywheel can be made smaller, reducing the power consumption of the starter motor and improving the starting performance of the vehicle, thereby improving the fuel consumption rate. can get.

[Brief explanation of the drawing]

Figure 1 is a front partial sectional view showing a conventional gasoline engine, Figure 2 is a sectional view showing the first embodiment of this invention, Figure 3 is an enlarged view of the throttle valve in Figure 2, and Figure 4. is a plan view of the intake manifold shown in FIG. 1, FIG. 5 is a sectional view of the actuator shown in FIG. 4,
FIG. 6 is a front view showing the spring fixed to the rod shown in FIG. 4, and FIG. 7 is a perspective view showing a second embodiment of this invention. 15...Cylinder hole, 19...Intake port, 2
4, 43, 45... Intake passage, 28, 46......
Throttle means (throttle valve, butterfly valve), 40, 65
...Control means, {62...Comparator, 63...Rotation speed sensor, 64...Reference voltage signal generator,} (Operating state determination means).

Claims (1)

[Scope of utility model registration request] In a gasoline engine having a cylinder hole, an intake port communicating with the cylinder hole, and an intake passage communicating with the intake port, a throttle means is provided in the intake passage near the intake port, and a means for determining an engine operating state; 1. A gasoline engine, comprising control means for switching the throttle means to a throttle position only when the engine is cranking, and for switching the throttle means to an open position when the engine is running.