JPH0541233Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an air intake tube for a vehicle that connects an outlet of an air cleaner case and an inlet of a compressor housing of a turbocharger.

(Prior Art) Conventionally, according to Japanese Patent Publication No. 60-56890, an air cleaner joint part that fits into the outlet of the air cleaner case and an air cleaner joint part that fits into the intake port of the compressor housing of the turbocharger are provided at both ends of the tube body. An air intake tube having a section is known, and in this case, the tube is formed in a straight shape with the air cleaner joint section and the compressor joint section having the same diameter, and the tube has an air intake tube at approximately the middle in the axial direction of the outer circumference of the tube. A connection port for the air hose for introducing fresh air is installed in the blow-by gas recirculation system of the engine.

(Problem to be solved by the invention) By the way, if the air flow velocity at the suction port of the compressor housing is slow, the air tends to separate from the low pressure area on the back side of the compressor blades, causing surging. Furthermore, when the flow velocity of air at the suction port exceeds the speed of sound, a choke phenomenon occurs. Therefore, it is desirable that the suction port of the compressor housing be formed as small in diameter as possible within a range where the air flow velocity does not exceed the sonic velocity.

However, if the thickness of the air intake tube is set to match the intake port of the compressor housing, the flow rate of the air inside the tube will increase, and a large negative pressure will be applied to the connection port of the air hose for introducing fresh air due to the ejector action. This may adversely affect the blow-by gas recirculation effect of the engine. That is, at low speeds, fresh air is prevented from flowing into the engine, and at high speeds, when blowby gas is exhausted from the connection port of the air hose for introducing fresh air, excessive blowby gas is sucked out.
Oil consumption will increase.

It is also possible to open a connection port for a relief air hose in the air intake tube to release air from the compressor outlet side and return excess air to the compressor intake port. In this case, however, the air blowing sound tends to leak to the outside through the air cleaner case, so the problem is how to prevent this.

The present invention was devised in view of these problems, and its purpose is to suppress the generation of negative pressure at the connection port of the air hose for introducing fresh air, and to reduce the amount of air blowing noise from the outside through the air cleaner case. An object of the present invention is to provide an air intake tube that can prevent leakage.

(Means for solving the problem) In order to achieve the above object, in the invention of claim 1,
In an air intake tube that has an air cleaner joint part that fits into the outlet of the air cleaner case and a compressor joint part that fits into the suction port of the compressor housing of the turbocharger at both ends of the tube body, the tube body has a bellows shape. The tube is formed so that the diameter gradually increases on the air cleaner joint side, and a connection port for an air hose for introducing fresh air to the blow-by gas recirculation system of the engine is provided near the air cleaner joint on the outer periphery of the tube body. At the same time, a connection port for a relief air hose for releasing air from the outlet side of the compressor was opened near the compressor joint on the outer periphery of the tube body.

In addition, the invention of claim 2 provides for a pressure chamber of a diaphragm type actuator that controls an exhaust gas flow rate control vane incorporated in a turbine housing to be quickly brought to atmospheric pressure at a portion near the compressor joint on the outer periphery of the tube body. In addition, an air hose connection port was opened to open the pressure chamber of the actuator to the atmosphere.

(Function) Since the air cleaner joint side of the tube body is formed with a large diameter, the air flow velocity in this part is slow, and a large negative pressure acts on the connection port opened near the air cleaner joint part of the tube body. In addition, by making the air cleaner joint side of the tube body larger in diameter, the intake resistance from the air cleaner case is reduced.

In addition, since the relief air hose connection port is formed on the compressor joint side of the tube body, the distance between the connection port and the air cleaner case can be increased, and since the tube body is formed into a bellows shape, it is possible to create a long distance between the connection port and the air cleaner case. The air blowing sound is diffusely reflected on the inner wall surface of the tube and is attenuated to some extent before reaching the air cleaner case, so that leakage of the air blowing sound to the outside via the air intake tube and the air cleaner case is suppressed.

In addition, the flow rate of air at the compressor joint of the tube body is high, and a large negative pressure is applied to the connection port established near the air cleaner joint of the tube body, which prevents air from escaping from the pressure chamber of the actuator. Get better.

(Example) One tube body is shown in the drawing, and the outlet 2a of the air cleaner case 2 is provided at both ends of the tube body 1.
The compressor joint part 1 fits into the air cleaner joint part 1a that fits into the air cleaner joint part 1a and the compressor joint part 1 which fits into the suction port 4a of the compressor housing 4 of the turbocharger 3.
The tube body 1 is formed in a bellows shape and has a diameter gradually increasing on the side of the air cleaner joint portion 1a. Then, a connection port 7 for an air hose 6 for introducing fresh air provided in the blow-by gas recirculation system of the engine 5 is opened near the air cleaner joint 1a on the outer periphery of the tube body 1, and a connection port 7 for an air hose 6 for introducing fresh air is provided in the blow-by gas recirculation system of the engine 5. A connection port 9 for a relief air hose 8 for releasing air from the outlet side of the compressor is provided near the joint portion 1b, and the tube body 1
The turbine housing 1 of the turbocharger 3 is located near the compressor joint portion 1b on the outer periphery.
A connection port 1 of an air hose 13 that opens the pressure chamber 12a of the diaphragm type actuator 12 that controls the exhaust gas flow rate control vane 11 incorporated in the exhaust gas flow rate control vane 1 to the atmosphere.
4 was opened.

As clearly shown in FIG. 5, the end of the relief air hose 8 is a diaphragm type relief valve formed by biasing a valve body 15b attached to a diaphragm 15a toward the closing side (downward in FIG. 5) with a spring 15c. 1
One pressure chamber 15e defined by the diaphragm 15a is connected to the downstream portion of the throttle valve 18 of the intake passage 17 of the engine 5 via the air passage 16, and the other pressure chamber 15e is connected to the outlet 15d of the engine 5. 1
5f to the portion of the intake passage 17 near the outlet of the compressor through the air passage 19, and the pressure difference between the pressure on the downstream side of the throttle valve 18 in the intake passage 17 and the pressure on the upstream side is greater than or equal to a set value. The valve body 15b is made to be able to move toward the opening side.

The actuator 12 is constructed by urging a diaphragm 12c attached with an actuating rod 12b connected to the exhaust gas flow rate control vane 11 toward the high speed side (to the right in FIG. 5) by a spring 12d, so that the pressure chamber of the actuator 12 12a is connected to a portion of the intake passage 17 near the compressor outlet via an air hose 20 having a regulator valve 19 interposed therebetween, and a first electromagnetic on-off valve is connected to a portion of the air hose 20 downstream of the regulator valve 19. 21 was opened, and the air hose 13 with a throttle 22 was branched from the downstream part of the valve 21 of the air hose 20. Furthermore, the diaphragm 1 of the actuator 12
The pressure chamber 12e on the opposite side of the pressure chamber 12a awakened in step 2c is communicated via an air hose 23 to the downstream side of the throttle valve 18 of the intake passage 17, and a check valve 24 and a second solenoid valve 2 are connected to the air hose 23.
5 were interposed in series.

The first solenoid valve 21 and the second solenoid valve 25
An electronic control circuit 26 is provided, and the control circuit 26 has a pressure signal P ₂ on the upstream side of the throttle valve 18 in the intake passage 17, a pressure signal P B on the downstream side of the throttle valve 18 in the intake passage 17, and a pressure signal P _B on the downstream side of the throttle valve 18 in the intake passage 17. Atmospheric pressure signal P _A ,
Intercooler downstream intake air temperature signal T _A , engine speed signal Ne, throttle valve opening signal θ _th , engine cooling water temperature signal T _W , vehicle speed signal V, and ignition switch signal IG are input, respectively, and these signals are used to control both. The opening degree of the exhaust gas flow rate control vane 11 is controlled by operating the valves 21 and 25.

That is, when θ _th is less than a predetermined set value, Ne
Determine the basic duty value from and θ _th , and further
This basic duty value is corrected and output using P _A , T _A , and T _W , and when θ _th is larger than the set value, Ne
Determine the target boost pressure from T _A , correct this target boost pressure using P _A and T _W , and perform proportional and integral calculations according to the deviation between the corrected target boost pressure and the actual boost pressure. output the corrected duty value, and use this output to
The duty of the electromagnetic valve 21 is controlled, and the opening degree of the exhaust gas flow rate control vane 11 is controlled so that the optimum supercharging pressure suitable for the operating condition of the engine 1 is obtained.

In addition, when low V, low Ne, low PB, low θ _th and low Δθ _th , in a 60 km/h cruising state where supercharging is not required, in 10 mode, or during slow acceleration, the electronic control circuit 26 opens the valve. A signal is output to the second solenoid valve 25.
The valve is opened and the intake negative pressure on the downstream side of the throttle valve 18 is applied to the pressure chamber 12e of the actuator 12 to increase the opening degree of the exhaust gas flow rate control vane 11 and prevent the vane 11 from becoming an exhaust resistance. I made it possible.

As explained in the above operation section, since the air cleaner joint part 1a side of the tube body 1 is formed to have a large diameter, the air flow velocity in this part becomes slow, and the part near the air cleaner joint part 1a of the tube body 1 A large negative pressure does not act on the connection port 7 opened in the tube body 1, and by making the diameter of the air cleaner joint portion 1a side of the tube body 1 large, the intake resistance from the air cleaner case 12 is reduced.

Also, when the differential pressure between the pressure downstream and upstream of the throttle valve 18 in the intake passage 17 increases, such as when the accelerator is suddenly released during high-speed operation,
This increase in differential pressure opens the relief valve 15, and the air on the outlet side of the compressor is released into the tube body 1 from the connection port 9 via the air hose 8, and at this time, air blowing noise is generated. However, since the connection port 9 is formed near the compressor joint portion 1b of the tube body 1, the distance between the connection port 9 and the air cleaner case 2 can be long, and the tube body 1 is shaped like a bellows. Therefore, the air blowing sound is diffusely reflected on the tube inner wall surface and is attenuated to some extent before reaching the air cleaner case 2, and as a result, leakage of the air blowing sound to the outside via the tube body 1 and the air cleaner case 2 is suppressed. .

Further, by closing the solenoid valve 21, the communication between the pressure chamber 12a of the actuator 12 and the intake passage 17 is cut off, and the air trapped in the pressure chamber 12a is released from the connection port 14 into the tube body, and the exhaust gas flow rate control vane is released. 11 is actuated to the high speed side by the urging force of the spring 12d via the actuating rod 12b. In this case, the flow velocity of the air in the compressor joint 1b of the tube body 1 is high, and a large negative pressure is applied to the connection port 14 opened in the vicinity of the compressor joint 1b of the tube body 1. Therefore, the actuator Air escape from the 12 pressure chambers 12a is improved.

(Effects of the invention) Since the invention is configured as described above, it has the following effects.

According to the invention of claim 1, suction resistance can be reduced while suppressing the occurrence of compressor surging, fresh air can be supplied without impairing the blow-by gas reflux action, and furthermore, the blowing sound of air released from the relief valve can be reduced. leakage to the outside can be suppressed.

Further, according to the invention of claim 2, in addition to the above-mentioned effects, it is possible to improve the ability of air to escape from the pressure chamber of the actuator, improve the responsiveness of the exhaust gas flow rate control vane, and ultimately reduce the time lag of the turbocharger. have

[Brief explanation of the drawing]

Fig. 1 is a front view showing an example of the air intake tube of the present invention, Fig. 2 is a partially cutaway plan view, Fig. 3 is a side view cut away along the line, and Fig. 4 shows the air intake tube equipped with the air intake tube. A plan view of the engine shown in FIG. 5 is an explanatory diagram. 1...Tube body, 1a...Air cleaner joint part, 1b...Compressor joint part, 2...Air cleaner case, 2a...Air cleaner case outlet, 3...Turbo charger,
4... Compressor housing, 4a... Compressor housing inlet, 5... Engine, 6
...Air hose for introducing fresh air, 7, 9, 14...
Connection port, 8...Relief air hose, 10...
... Turbine housing, 11 ... Exhaust gas flow rate control vane, 12 ... Actuator, 12a ... Pressure chamber of actuator, 13 ... Air hose.

Claims (1)

[Claims for Utility Model Registration] 1. An air intake having, at both ends of the tube body, an air cleaner joint part that fits into the outlet of the air cleaner case and a compressor joint part that fits into the intake port of the compressor housing of the turbocharger. In the tube, the tube body is formed in a bellows shape and the diameter gradually increases on the air cleaner joint side,
A connection port for an air hose for introducing fresh air installed in the blow-by gas recirculation system of the engine is provided near the air cleaner joint on the outer periphery of the tube body, and a connection port for an air hose for introducing fresh air is provided on the outer periphery of the tube body near the compressor joint. An air intake tube for a vehicle, characterized in that it has a connection port for a relief air hose that releases air from the outlet side of a compressor. 2. An air hose connection port for opening the pressure chamber of the diaphragm-type actuator that controls the exhaust gas flow velocity control vane incorporated in the turbine housing of the turbocharger to the atmosphere is provided near the compressor joint on the outer periphery of the tube body. The air intake tube for a vehicle according to claim 1.