JPH0420988Y2 - - Google Patents

Description

[Detailed explanation of the idea] B. Purpose of the invention E-1 Industrial application fields The present invention relates to an intake system for an internal combustion engine.

A-2 Prior Art Conventionally, as an intake system for an internal combustion engine, as shown in FIG. Generally, a throttle valve 3 which is closed substantially perpendicularly is disposed so as to be opened and closed by rotation, and a throttle shaft 4 of the throttle valve 3 is provided perpendicularly to the intake flow. Also,
As shown in FIG. 6, a piston-type throttle valve that forms an intake passage 6 of the intake cylinder 5 linearly and moves back and forth in a direction perpendicular to the intake air flow flowing through the intake passage 6 to control the intake air flow rate. There is also a so-called Amal type type in which 7 is provided (for example, Japanese Utility Model Publication No. 58-56359).

A-3 Problems to be Solved by the Present Invention In the type shown in FIG. Because the throttle valve is balanced without being given any rotational moment by the negative pressure in the intake pipe, the throttle valve downstream of the throttle valve caused by the differential pressure upstream and downstream of the throttle valve 3 is The pulling force is directly transmitted to the bearing portion of the throttle shaft 4, and the throttle shaft 4 comes into pressure contact with the lower surface of the bearing, thereby increasing the frictional resistance during its rotation. This frictional resistance force becomes particularly large when the differential pressure between the upstream and downstream sides of the throttle valve 3 is large, that is, in the region where the throttle valve begins to open from the idle opening position and where the accelerator pedal begins to be depressed. There are problems with deterioration in the operability of the engine and increased pressure on the accelerator pedal. Also, in the Amal type shown in FIG. 6, the downstream wall surface of the throttle valve 7 is pushed into the cylinder chamber 8 by the differential pressure between the upstream and downstream sides of the throttle valve 7 caused by the intake air flow.
The pressure contact part increases the sliding frictional resistance of the throttle valve, and especially at the idle opening with a large differential pressure, the sliding frictional resistance becomes large, and as described above. There is a problem that the operability of the throttle valve deteriorates and the accelerator operation force becomes heavy.

Therefore, the present invention is designed to operate the valve member with a small actuation force without increasing the frictional resistance force as described above, even when the differential pressure between the upstream and downstream sides of the intake passage bordering the valve member that controls the intake air amount is large. The purpose is to solve the above-mentioned problems by enabling smooth operation.

B. Structure of the invention B-1. Means for solving the problems In order to solve the above-mentioned problems, the present invention bends the intake passage at right angles in the intake pipe 9 and connects the upstream side of the intake passage to the inlet side intake passage 10. and the downstream side is the outflow side intake passage 1
1, and a piston-type intake air amount control valve 14 is disposed in the bent portion so as to move forward and backward along the axis of the outflow-side intake passage 11, facing the bent-side opening of the outflow-side intake passage 11. A cylinder chamber that is slidably provided in the intake cylinder 9, and a pressure balance chamber 18 that communicates with the inflow side intake passage 10 is provided on the side circumference of the intake air amount control valve 14, and that slides and guides the intake air amount control valve 14. 16 and the outflow side intake passage 11 are provided, and the intake air amount control valve 14 is provided with means for moving it forward and backward by accelerator operation. Intake passage 11
The distal end surface 14c facing the outflow side intake passage 11
It is characterized by being formed into an inclined surface protruding in the direction of.

RO-2 Effect Negative pressure is generated in the outflow side intake passage 11 due to engine operation, and the pressure in the passage 11 and the intake air amount control valve 1 are
A differential pressure is generated between the pressure in the inflow side intake passage 10 on the upstream side with the boundary at 4 as the boundary. However, the pressures in the inflow side intake passage 10 and the pressure balance chamber 18 become the same pressure, and the pressure in the outflow side intake passage 11 and the cylinder chamber 16 that faces it via the intake air amount control valve 14 becomes the same pressure. This prevents the intake air amount control valve 14 from coming into pressure contact with the inner circumferential surface of the cylinder chamber 16 due to the pressure difference, increasing the sliding frictional resistance force, or being drawn toward the outflow side intake passage 11. do not have. Therefore, the operating torque of the intake air amount control valve 14 does not increase due to the differential pressure. Also,
Since the tip end surface 14c of the intake air amount control valve 14 is formed as an inclined surface projecting toward the outflow side intake passage 11, the intake air flowing from the inflow side intake passage 10 to the outflow side intake passage 11 is directed to the inclined surface. Induced inflow.

RO-3 Embodiment Next, a first embodiment of the present invention shown in FIGS. 1 and 2 will be described.

Reference numeral 9 denotes an intake cylinder, and its inflow side intake passage 10 and outflow side intake passage 11 are bent at right angles. Reference numeral 12 denotes an idle intake passage which communicates the inflow side intake passage 10 and the outflow side intake passage 11 in a bypass manner, and an adjusting screw 13 is provided in the middle of the passage 12. Reference numeral 14 denotes an intake air amount control valve formed in the shape of a bottomed piston.
The intake pipe 9 is slidably provided in the intake pipe 9 so as to move forward and backward along the axis of the passage 11 facing the opening of the passage 11, and in its most advanced state, the outflow side intake passage 1
By closing the air amount control section 15 of No. 1 and retracting from this state, the communication area between the inflow side intake passage 10 and the outflow side intake passage 11 is increased in proportion to the amount of retraction, and the intake flow rate is increased. The government is beginning to aim for this.
The rear part 14a of the intake air amount control valve 14 is always slidably in contact with the inner circumferential surface 16a of the cylinder chamber 16 formed in the intake pipe 9, so that the inflow side intake passage 10 and the cylinder chamber 16 are not directly communicated with each other. There is.

A spring 17 biases the intake air amount control valve 14 in the advancing direction. 18 is located on the same plane as the inflow side intake passage 10 and is connected to the intake air amount control valve 1.
This is a pressure balance chamber formed around 4, and is always in communication with the inflow side intake passage 10. Reference numeral 19 denotes a communication passage formed in the bottom wall 14b of the intake air amount control valve 14, which communicates the outflow side intake passage 11 and the cylinder chamber 16 so that the pressure in the cylinder chamber 16 and the outflow side intake passage 11 is always the same. I have to. The tip end surface 14c of the bottom wall 14b of the intake air amount control valve 14 is formed into a curved surface that projects in the downstream direction from the side end located on the outflow side intake passage 10 side.
20 is an accelerator wire, the tip of which is fixed to the intake air amount control valve 14. 21 is a sealing gasket.

Next, the operation of this embodiment will be explained. In the idle state, as shown in FIG.
closes the air amount control unit 15 of the outflow side intake passage 11, and the air adjusted by the adjusting screw 13 from the idle intake passage 12 flows into the outflow side intake passage 11.
supplied to In this idle state, the inside of the inflow side intake passage 10 and the pressure balance chamber 18 are at the same pressure, and the inside of the outflow side intake passage 11 and the cylinder chamber 16 are at the same pressure.
and are at the same pressure through the communication passage 19. Next, when the accelerator wire 20 is pulled from this idle state to perform an acceleration operation, the intake air amount control valve 14 retreats against the spring 17, and the communication area between the inflow-side intake passage 10 and the outflow-side intake passage 11 is reduced by the accelerator wire. It increases in proportion to the amount of pull of 20. Also, by returning the accelerator wire 20, the spring 1
The intake air amount control valve 14 moves forward due to the load 7, and the communication area decreases in proportion to the amount of return of the unsell wire 20. The amount of air is controlled by increasing or decreasing this communication area, and the operation of the engine is controlled. When the intake air amount control valve 14 moves back and forth, the pressure inside the inflow side intake passage 10 bordering on the intake air amount control valve 14 and the pressure inside the pressure balance chamber 18 on the opposite side are the same pressure; , the outflow side intake passage 11 and the cylinder chamber 16, which face each other with the intake air amount control valve 14 in between, have the same pressure in the forward and backward directions of the intake air amount control valve 14, so that the inflow side intake passage Even if a pressure difference occurs between the pressure inside the cylinder chamber 10 and the pressure inside the outflow side intake passage 11, the intake air amount control valve 14 comes into pressure contact with the inner circumferential surface of the cylinder chamber 16 due to the pressure difference, resulting in a sliding frictional resistance force. will not increase or be drawn toward the outflow side intake passage 11. Therefore, the operating torque of the intake air amount control valve 14 does not increase due to the differential pressure, and the operating torque can be reduced.

Furthermore, since the tip surface 14c of the intake air amount control valve 14 is formed into a curved surface as shown in the figure, the intake air flowing from the inflow side intake passage 10 to the outflow side intake passage 11 flows along the curved surface. So,
Resistance to the intake air flow when passing through the intake air amount control valve 14 can be reduced.

In addition, in the above embodiment, the outflow side intake passage 11
In order to communicate between the cylinder chamber 16 and the cylinder chamber 16, instead of the communication passage 19 as described above, as shown by the dotted line in the figure,
A bypass communication passage 21 may be used in which one end opens into the outflow side intake passage 11 and the other end opens into the cylinder chamber 16.

Further, the shape of the tip end surface 14c of the intake air amount control valve 14 may be formed into a linear tapered surface as shown in FIG. 3, or may be formed into a conical surface as shown in FIG. .

C. Effect of the invention As described above, according to the invention, the sliding friction force of the intake air amount control valve increases due to the differential pressure between upstream and downstream caused by the intake flow, and the closing force is applied to the intake air amount control valve. The operating torque of the intake air amount control valve is reduced compared to conventional models, and the intake air amount can be controlled smoothly with a small torque.
It has the advantage of improving its operability and making driving easier with lighter accelerator operation. Furthermore, the intake air amount control valve 14
The tip surface 1 facing the outflow side intake passage 11 in
4c is formed as an inclined surface projecting in the direction of the outflow side intake passage 11, so that resistance to the intake air flow when passing through the intake control valve 14 section is reduced, and air can be sent efficiently without disturbing the intake air flow. can be provided.

Further, by setting the inclined shape of the tip end surface 14c as desired, there is a feature that the amount of air to be supplied with respect to the stroke of the accelerator wire can be set as desired, and the flow direction can be set as desired.

[Brief explanation of drawings]

FIG. 1 is a side sectional view showing the first embodiment of the present invention;
Fig. 2 is a sectional view taken along the line A-A in Fig. 1, Figs. 3 and 4 are side sectional views showing the second and third embodiments of the present invention, and Figs. 5 and 6 are sectional views of the conventional type. It is a schematic sectional view showing two examples. 9... Intake cylinder, 10... Inflow side intake passage, 11
...Outflow side intake passage, 14...Intake amount control valve, 1
4c... Tip surface, 16... Cylinder chamber, 17...
Spring, 18... Pressure balance chamber, 19,2
1...Communication path, 20...Accelerator wire.

Claims (1)

[Scope of utility model registration request] An intake passage is bent at right angles in the intake cylinder 9, and the upstream side is an inflow side intake passage 10, the downstream side is an outflow side intake passage 11, and a piston-type intake air amount control valve 14 is installed in the bent part, and an outflow side intake passage 11 is formed downstream. It is slidably provided in the intake cylinder 9 so as to face the bent side opening of the side intake passage 11 and move forward and backward along the axis of the outflow side intake passage 11;
A pressure balance chamber 18 that communicates with the inflow side intake passage 10 is provided on the side circumference of the intake air amount control valve 14, and a cylinder chamber 16 that slides and guides the intake air amount control valve 14 and the outflow side intake passage 11 are connected to each other. A communicating path is provided, and the intake air amount control valve 14 includes:
A means for advancing and retracting this by operating the accelerator is provided, and furthermore, the tip end face 14c of the intake air amount control valve 14 facing the outflow side intake passage 11 is formed into an inclined surface projecting in the direction of the outflow side intake passage 11. Features of internal combustion engine intake system.