JPH03194122A - Composite-type supercharging device for vehicular internal combustion engine - Google Patents

Abstract

PURPOSE:To facilitate travel speed regulating control by providing a mechanical supercharger and an exhaust turbosupercharger in series, as well as providing a switching valve in an intake bypass passage bybassing the mechanical supercharger, and closing this switching valve at the time of travel speed exceeding the specified maximum set speed. CONSTITUTION:In an intake path, an exhaust turbosupercharger 5 and a mechanical supercharger 8 driven by power transmission from an internal combustion engine 1 are disposed in series. An intake passage 19 from the supercharged air exhaust port of an exhaust turbosupercharger 5 is connected to the entrance of the mechanical supercharger 8, and the exit of the mechanical supercharger 8 is connected to a throttle body 17 through a supercharging passage 21 provided with an intercooler 20. A bypass passage 22 for bypassing the mechanical supercharger 8 is provided between the intake passage 19 and supercharging passage 21, and a normally closed type switching valve 24 is interposed at the intermediate part of the bypass passage 22. This switching valve 24 is controlled to be opened when power transmission to the mechanical supercharger 8 is cut off in the high speed rotating region and closed again when the travel speed exceeds the specified maximum set travel speed.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention uses an exhaust turbo supercharger driven by exhaust gas in the internal combustion engine and a power source from the internal combustion engine to supercharge an internal combustion engine installed in a vehicle. This invention relates to a so-called composite type supercharging device that uses both a mechanical supercharger and a mechanical supercharger driven by transmission in series.

[Conventional technology]

In general, a composite supercharging system that uses both an exhaust turbo supercharger and a mechanical supercharger in series for supercharging an internal combustion engine is well known, and Japanese Patent Laid-Open No. 62
Publication No. 87618 discloses that in the intake path from the air cleaner to the internal combustion engine, and in the intake path from the air cleaner to the internal combustion engine mounted on the vehicle, power is transmitted from the internal combustion engine in the low speed rotation range below medium speed rotation. A rotationally driven mechanical supercharger and an exhaust turbo supercharger driven by exhaust gas are arranged in series, and the mechanical supercharger is installed in an intake bypass passage that bypasses the mechanical supercharger. We have proposed a composite supercharging device that is equipped with an on-off valve that closes when the machine is rotating.

Further, as another prior art, Japanese Patent Application Laid-Open No. 54-35 I-516 discloses that when an internal combustion engine equipped with an exhaust turbo supercharger is installed in a vehicle, an intake bypass that bypasses the exhaust turbo supercharger is disclosed. By providing a blow-off valve in the passage that opens when the vehicle travel speed exceeds a predetermined maximum set travel speed, the maximum travel speed of the vehicle is regulated and the exhaust turbo supercharger is bypassed. It is proposed that the maximum running speed of a vehicle be regulated and controlled by providing a wastegate valve in the exhaust bypass passage that opens when the running speed of the vehicle exceeds a predetermined maximum set running speed. .

[Problem to be solved by the invention]

However, when the maximum traveling speed regulating device in the latter prior art is applied to a vehicle internal combustion engine equipped with the composite supercharging device in the former prior art described above, the following problems arise.

That is, since the composite supercharging device does not require a blow-off valve for its exhaust turbo supercharger, in an internal combustion engine for a vehicle equipped with the composite supercharging device, the intake path of the vehicle is Providing an intake bypass passage with a speed-related blow-off valve not only increases size and weight, but also increases the number of parts and significantly increases cost.

In addition, in a composite supercharging system, a wastegate valve is required for the exhaust turbosupercharger, so while this wastegate valve has the advantage of being able to be used to regulate and control the maximum running speed, Even when the wastegate valve in the exhaust bypass passage is open, the engine continues to rotate at high speed for a while due to inertia, so the responsiveness of the regulation control of the traveling speed is low.

The present invention makes it possible to regulate and control the maximum running speed of a vehicle very simply, quickly, and reliably without causing the above-mentioned problems when the composite supercharging device is applied to an internal combustion engine for a vehicle. It is an object of the present invention to provide a composite supercharging device as described above.

[Means to solve the problem]

In order to achieve this object, the present invention provides a mechanical supercharging device that is rotatably driven by power transmission from the internal combustion engine in the low speed rotation range below medium speed rotation, in the intake path from the air cleaner to the internal combustion engine installed in the vehicle. and an exhaust turbo supercharger driven by exhaust gas are arranged in series, and an intake bypass passage that bypasses the mechanical supercharger is closed when the mechanical supercharger is driven to rotate. In the composite supercharging device comprising an on-off valve as described above, the on-off valve is configured to have a control means that closes the on-off valve when the traveling speed of the vehicle exceeds a predetermined maximum set traveling speed. The structure was designed to provide the following.

[For production]

In such a configuration, in a low speed rotation range, the mechanical supercharger is rotationally driven and the on-off valve in the intake bypass passage is closed, so that supercharging of the internal combustion engine is performed by the mechanical supercharger and the exhaust turbo. However, in high-speed rotation ranges, the power transmission to the mechanical supercharger is cut off, and the on-off valve in the intake bypass passage opens, so that supercharging of the internal combustion engine is not performed. , carried out solely by the exhaust turbocharger.

In this high-speed rotation range, when the running speed of the vehicle reaches a predetermined maximum running speed, with the power transmission to the mechanical supercharger being cut off,
By closing the on-off valve in the intake bypass passage,
Intake air to the internal combustion engine passes through the mechanical supercharger in a state where power transmission from the internal combustion engine is cut off, so that the mechanical supercharger provides resistance to the flow of intake air. The supercharging intake pressure to the internal combustion engine decreases by this amount of resistance, and the rotational speed of the internal combustion engine decreases, so that the running speed of the vehicle does not exceed the predetermined maximum set running speed. It can be regulated and controlled.

〔Effect of the invention〕

As described above, the present invention utilizes the flow resistance when intake air to the internal combustion engine passes through a mechanical supercharger whose rotation is stopped to determine the maximum running speed of a vehicle equipped with an internal combustion engine equipped with a composite supercharger. This is because it is only necessary to configure the on-off valve in the intake bypass passage, which is necessary in the composite supercharging device, to open and close according to the running speed of the vehicle. ,Upsizing,
This method does not cause an increase in weight or a significant increase in price, and since the closing operation of the on-off valve directly lowers the supercharging intake pressure to the internal combustion engine, it is possible to control the maximum running speed. The responsiveness of the system is extremely high, and the maximum travel speed can be controlled quickly and accurately.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, reference numeral 1 indicates an internal combustion engine equipped with an intake port 3 to a combustion chamber 2 and an exhaust port 4 from the combustion chamber, and reference numeral 5 indicates an exhaust turbine 6. and a blower-compressor 7 are directly connected to each other, and numeral 8 indicates a mechanical supercharger which is rotationally driven by power transmitted from the internal combustion engine 1.

On the inlet side of the exhaust turbine 6 in the exhaust turbocharger 5, there is an exhaust passage 9 from the exhaust port 4 in the internal combustion engine l, and on the outlet side of the exhaust turbine 6, there is an exhaust passage 9 for discharging exhaust gas into the atmosphere. Exhaust pipes 10 are connected to each other, and an exhaust bypass passage 11 that bypasses the exhaust turbine 6 is provided between the exhaust passage 9 and the exhaust pipe 10. A wastegate valve 13 is provided which is normally held closed by a spring 12a within the diaphragm mechanism 12. Further, an air cleaner 1 for taking in atmospheric air is provided at the inlet of the blower compressor 7 in the exhaust turbo supercharger 5.
Furthermore, the power transmission section from the internal combustion engine 1 to the mechanical supercharger 8 includes an electromagnetic clutch mechanism 15 for turning on and off the power transmission to the mechanical supercharger 8.
is provided.

A surge tank 18 having a throttle body 17 with a built-in throttle valve 16 is connected to the intake port 3 of the internal combustion engine 1, while a surge tank 18 is connected to the intake port 3 of the internal combustion engine 1.
Intake passage 19 from the discharge port of the blower compressor 7 in
is connected to the inlet of the mechanical supercharger 8, and the outlet of the mechanical supercharger 8 is connected to the throttle body 17 of the surge tank 18 via a supercharging passage 21 provided with an intercooler 20. Further, the intake passage 1
9 and the supercharging passage 21, the mechanical supercharger 8
An intake bypass passage 22 is provided to bypass the intake air, and an on-off valve 24 that is normally kept closed by a spring 23a of a diaphragm mechanism 23 is provided in the intake bypass passage 22.

On the other hand, the diaphragm mechanism 1 of the waste gate valve 13
A pressure transmission passage 25 with a throttle orifice 26 from the supercharging passage 21 is connected to the pressure chamber 12b in 2,
The waste gate valve 13 is configured to open when the pressure acting on the pressure chamber], 2b becomes higher than a predetermined supercharging intake pressure, and the pressure transmission passage 25 is connected to the air cleaner 14, etc. An atmosphere communication passage 27 with a throttle orifice 28 from the communication point is connected to the atmosphere communication passage 27, and an electromagnetic switching valve 29 for opening and closing the atmosphere communication passage 27 is provided in the atmosphere communication passage 27.

Further, in the diaphragm mechanism 23 for the on-off valve 24, a pressure transmission passage 30 from the supercharging passage 21 is connected to one pressure chamber 23c partitioned by the diaphragm 23b.
The on-off valve 24 is configured to open against the spring 23a when the supercharging intake pressure in the supercharging passage 21 increases, while the pressure transmission passage to the other pressure chamber 23d in the diaphragm mechanism 23 is connected to the 31 and a pressure transmission passage 32 from the surge tank 18 and a pressure transmission passage 33 from the supercharging passage 21, three types of first electromagnetic switching valves 34 are provided.

Furthermore, a vacuum holding tank 35 is connected to the surge tank 18 through a passage 36, and a check valve 37 is provided in the passage 36, which opens only in the direction toward the surge tank 18.
By providing a vacuum pressure lower than atmospheric pressure in the vacuum holding tank 35, a vacuum transmission passage 38 from the vacuum holding tank 35 and the first electromagnetic switching valve 3 are provided.
A second electromagnetic switching valve 39 of three types is provided between the pressure transmitting passage 33 and the pressure transmission passage 33 to the pressure transmitting passage 33 to the pressure transmitting passage 33 to the pressure transmitting passage 33 to the pressure transmitting passage 33 to the pressure transmitting passage 33 to the pressure transmitting passage 33 to the pressure transmitting passage 33 to the pressure transmitting passage 33 to the pressure transmitting passage 33 to the pressure transmitting passage 33.

Reference numeral 40 denotes a rotation sensor 41 for the internal combustion engine 1, an opening sensor 42 for the throttle valve 16, a pressure sensor 43 for the surge tank I8, and a running speed sensor 4 for the running speed of the vehicle.
4, the electromagnetic clutch mechanism 15
and a control circuit for operating the three types of electromagnetic switching valve 29 and the two types of electromagnetic switching valves 34 and 39 as described below.

In other words, this control circuit 40 operates as follows: (1) When the rotational speed of the internal combustion engine 1 is 3500 to 400;
When the operating speed is low, lower than a medium rotation speed of about 0 rpm, and the operating load is high, the electromagnetic clutch mechanism 15 is turned on, the three types of electromagnetic switching valves 29 are closed, and the first electromagnetic switching valve 34 is set to pressure. A first switching state is established in which only the transmission passages 31 and 32 communicate with each other.

(■) When the load is low and the rotational speed is in a low-speed operation range lower than the medium-speed rotational speed, the electromagnetic clutch mechanism 15
is turned OFF, and the three types of electromagnetic switching valves 29 are closed, while the first electromagnetic switching valve 34 is switched to the pressure transmission passage 31. ．． A second switching state is established in which the communication between the pressure transmission passages 31 and 32 is cut off and only the pressure transmission passages 31 and 33 are communicated with each other, and the second electromagnetic switching valve 39 is placed in a second switching state in which communication between the pressure transmission passages 33 and the vacuum transmission passage 38 is cut off. A first switching state is established in which the pressure transmission passage 33 is placed in a communicating state.

(■) When the load is high and the rotation speed is in a high speed operation range higher than the medium speed rotation speed, the electromagnetic clutch mechanism 15
OFF and switch the three-way electromagnetic switching valve 29 to open, while keeping the first electromagnetic switching valve 34 in the second switching state, and switch the second electromagnetic switching valve 39 between the pressure transmission passage 33 and the vacuum transmission passage 38. A second switching state is established in which the two terminals are in communication with each other.

(■) When operating under low load and high speed rotation, the electromagnetic clutch mechanism 15 is turned OFF and the three-way electromagnetic switching valve 29 is switched to open, while the first electromagnetic switching valve 34 is switched to the second switching state. While keeping the switch in place, the second electromagnetic switching valve 39 is set to the first switching state.

(■) In the high-speed rotation/high-load operating range in (III) above, when the running speed of the vehicle reaches a predetermined maximum set running speed, the electromagnetic clutch mechanism 15 is turned OFF, and the three electromagnetic With the switching valve 29 switched to open, the first electromagnetic switching valve 34 is set to the second switching state and the second electromagnetic switching valve 39 is set to the first switching state, or the first electromagnetic switching valve 34 is switched to the first switching state. The second electromagnetic switching valve 39 is placed in the second switching state.

It is configured as follows.

In this configuration, when the internal combustion engine rotates at low speed and is in a high load operating range, the electromagnetic clutch mechanism 15 is turned on and the mechanical supercharger 8 is rotationally driven, while the first electromagnetic switching valve 34 is In the switching state, the supercharging intake pressure in the sensor tank 18 (at this time,
- Since the throttle valve I6 is substantially fully open, the supercharging intake pressure in the tank 8 is approximately equal to the supercharging intake pressure in the supercharging passage 21, and the other pressure chamber 23b and the By eliminating the pressure difference between the supercharging intake pressure in the supercharging passage 21 and one pressure chamber 23c that is constantly acting via the pressure transmission passage 30,
Since the on-off valve 24 is closed by the spring 23a, the internal combustion engine 1 is supercharged by both the exhaust turbo supercharger 5 and the mechanical supercharger 8.

On the other hand, in this operating range, the three-way electromagnetic switching valve 29 is closed, so that the supercharging intake pressure in the supercharging passage 21 directly acts on the pressure chamber 12b in the diaphragm mechanism 12 for the waste gate valve 13. Therefore, when the supercharging intake pressure in the supercharging passage 21 exceeds the set value of the spring I2a that urges the wastegate valve 13 to close, the wastegate valve 13 opens wide and the supercharging intake pressure increases. control so that it does not rise.

Next, when the internal combustion engine 1 is operated at low speed and low load, the electromagnetic clutch mechanism 15 is turned OFF and power transmission to the mechanical supercharger 8 is cut off, while the first electromagnetic The switching valve 34 is in the second switching state, and the second electromagnetic switching valve 39 is in the second switching state.
is in the first switching state, and the supercharging passage 2 is connected to the other pressure chamber 23d in the diaphragm mechanism 23 for the on-off valve 24.
The supercharging intake pressure in 1 acts, and the other pressure chamber 2
3d and one pressure chamber 23c disappears, and the on-off valve 24 is closed by the spring 23a, so that
Since the supercharged air compressed in the exhaust turbo supercharger 5 is sent to the mechanical supercharger 8, the mechanical supercharger 8 can be rotated at an appropriate speed, while this operation Similarly to the above, the supercharging intake pressure in the supercharging passage 2
1 and is controlled only by the boost intake pressure.

Further, when the internal combustion engine 1 is in a high-speed rotation and low-load operating range, the electromagnetic clutch mechanism 15 is turned off and power transmission to the mechanical supercharger 8 is cut off, while the first electromagnetic switching valve 34 is turned off. In the second switching state, the second electromagnetic switching valve 39 becomes the first switching state, and the on-off valve 24 is closed by the spring 23a, so that the supercharged air compressed in the exhaust turbo supercharger 5 is transferred to the mechanical supercharger. Since it is sent to feeder 8, as a result,
The mechanical supercharger 8 can follow the rotation at an appropriate speed.

On the other hand, in this operating range, the three-way electromagnetic switching valve 29 opens, so that the pressure chamber 12b in the diaphragm mechanism 12 for the wastegate valve 13 is connected to the supercharging intake pressure in the supercharging passage 21 and the atmospheric pressure. When a composite pressure is applied and this composite pressure exceeds the set value of the spring 12a that urges the wastegate valve 13 to close, the wastegate valve 13 opens and exhaust gas is transferred to the exhaust bypass passage 11.
As a result, the supercharging passage 2
The supercharging intake pressure in the engine 1 can be controlled by the combined pressure so that it does not exceed a predetermined set supercharging intake pressure.

When the internal combustion engine 1 is in a high-speed rotation and high-load operating range, the electromagnetic clutch mechanism 15 is turned off and power transmission to the mechanical supercharger 8 is cut off, while the first electromagnetic switching valve 34 is turned off. In the second switching state, the second electromagnetic switching valve 39 is in the second switching state.
In the switching state, the vacuum in the vacuum holding tank 35 is transmitted to the other pressure chamber 23d in the diaphragm mechanism 23 for the on-off valve 24, and the vacuum in the vacuum holding tank 35 is transferred to the other pressure chamber 23d.
A pressure difference is created between the two pressure chambers 23c and 23c, and this pressure difference opens the on-off valve 24, so the supercharged air from the exhaust turbocharger 5 passes through the mechanical supercharger 8. Therefore, air is taken into the internal combustion engine 1 via the intake bypass passage 22, and supercharging is performed only by the exhaust turbo supercharger 5, and the following rotation of the mechanical supercharger 8 is not performed. Similarly to the above, the supercharging intake pressure at this time can also be controlled by the combined pressure so that it does not exceed a predetermined set supercharging intake pressure.

Further, when the running speed of the vehicle reaches a predetermined maximum set running speed in a high-speed rotation and high-load operating range of the internal combustion engine 1, the first electromagnetic switching valve 34 is switched to the second switching state. Then, the second electromagnetic switching valve 39 enters the first switching state, or the first electromagnetic switching valve 34 enters the first switching state and the second electromagnetic switching valve 39 enters the second switching state. The other pressure chamber 23d and one pressure chamber 2 in the diaphragm mechanism 23 for
3c is eliminated, the on-off valve 24 is closed by the spring 23a, and the supercharged air compressed in the exhaust turbo supercharger 5 is sent to the mechanical supercharger 8. , the mechanical supercharger 8 can be rotated at an appropriate speed, and the supercharging intake pressure by the exhaust turbo supercharger 5 is sufficient to cause the mechanical supercharger 8 to follow the rotation as described above. Since the rotational speed of the internal combustion engine 1 decreases by an amount corresponding to the flow resistance, the traveling speed of the vehicle can be controlled so as not to exceed a predetermined maximum set traveling speed.

Note that if a throttle orifice 45 is provided in the supercharging passage 21 from the mechanical supercharger 8, the supercharging intake to the internal combustion engine 1 will be restricted when the vehicle travel speed reaches a predetermined maximum speed. Since the atmospheric pressure can be lowered to a lower level, the maximum running speed can be controlled more effectively. Therefore, the output of the internal combustion engine I will not be reduced in the case where the traveling speed regulation control is not performed.

[Brief explanation of drawings]

The drawings are diagrams showing embodiments of the invention. 1... Internal combustion engine, 5... Exhaust turbo supercharger, 8
... Mechanical supercharger, 11 ... Exhaust bypass passage, 13 ... Waste gate valve, 14 ... Air cleaner, 15 ... Electromagnetic clutch mechanism, 16 ...
Throttle valve, 18...Surge tank, 19...
・Intake passage, 21...Supercharging passage, 22...Intake bypass passage, 24...Opening/closing valve, 23...Diaphragm mechanism, 34...First electromagnetic switching valve, 39・・・
...Second electromagnetic switching valve, 40...Control circuit, 41...
... Rotation sensor 42 ... Throttle valve opening sensor 43 ... Pressure sensor 44 ... Traveling speed sensor 9

Claims (1)

[Claims] (1) In the intake path from the air cleaner to the internal combustion engine installed in the vehicle, there is a mechanical supercharger that is driven to rotate by power transmission from the internal combustion engine in the low speed range below medium speed rotation, and a mechanical supercharger that is driven by the power transmitted from the internal combustion engine. A driven exhaust turbo supercharger is arranged in series, and an on-off valve is provided in an intake bypass passage that bypasses the mechanical supercharger and is closed when the mechanical supercharger is driven to rotate. The combined supercharging device is characterized in that the on-off valve is provided with a control means that closes the on-off valve when the traveling speed of the vehicle exceeds a predetermined maximum set traveling speed. A composite supercharging device for internal combustion engines for vehicles.