JPH0322519Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a supercharged engine equipped with a pressure wave supercharger, and particularly relates to countermeasures when the pressure wave supercharger locks up.

(Prior Art) A pressure wave supercharger has been known as one of the superchargers for supercharging intake air to an engine (see Japanese Patent Publication No. 1153/1983). This pressure wave supercharger includes a rotor that is rotatably supported within a case and has a number of partition walls arranged radially to form a number of small chambers, and an air intake inlet formed in the case at one end of the rotor. and an intake outlet, and an exhaust inlet and an exhaust outlet formed in the case on the other end side of the rotor, and as the rotor rotates, the intake air drawn into the small chamber of the rotor from the intake inlet is On the other hand, the exhaust air is caused to flow into the small chamber from the exhaust inlet, and the intake air is compressed and accelerated by the pressure difference between the two and then discharged from the intake outlet.In other words, by transmitting the pressure wave energy of the exhaust air to the intake air, While supplying air, exhaust gas remaining in the small chamber is discharged from the exhaust outlet, and scavenging is repeated by introducing intake air into the small chamber from the intake inlet.

(Problem to be solved by the invention) However, in an engine equipped with a pressure wave supercharger as described above, when the pressure wave supercharger becomes locked due to intrusion of foreign matter, its rotation stops and In addition to causing damage, due to the above-mentioned stop, the exhaust gas in the exhaust passage flows into the intake passage through the inside of the pressure wave supercharger due to the pressure difference with the intake passage.
A problem arises in that the engine also stops and the vehicle cannot be driven.

The present invention was devised in view of this point, and when the pressure wave supercharger is locked as described above, even if the rotation stops, the exhaust air is prevented from flowing into the intake passage while allowing intake and exhaust. By doing so, the purpose is to at least maintain engine operation and ensure running performance.

(Means for Solving the Problem) In order to achieve the above object, the solution of the present invention is to provide an intake passage upstream of the intake inlet in a supercharged engine equipped with a pressure wave supercharger as described above. and an intake passage downstream of the exhaust discharge port, bypassing the pressure wave supercharger, and connecting the exhaust passage upstream of the exhaust inlet and the exhaust passage downstream of the exhaust discharge port, bypassing the pressure wave supercharger. an exhaust bypass passage that communicates with the intake passage, an intake bypass valve and an exhaust bypass valve that open and close the intake bypass passage and the exhaust bypass passage, respectively, and a pressure wave supercharger that blocks communication between the intake passage and the exhaust passage. A shutoff valve should be provided. In addition, in order to detect when the pressure wave supercharger is locked, a rotation speed detection means is provided for detecting a signal related to the rotation speed of the rotor, and upon receiving the signal from the detection means, the lock state of the rotor is detected. The present invention is configured to include a control means that opens the intake bypass valve and the exhaust bypass valve and closes the cutoff valve when the intake bypass valve and the exhaust bypass valve are detected.

(Function) With the above configuration, in the present invention, when the pressure wave supercharger is locked, the rotation of its rotor stops, so when the pressure wave supercharger is locked, the lock is detected, and the control means opens the intake bypass valve and the exhaust bypass valve. At the same time, the intake bypass passage and the exhaust bypass passage are opened, and the cutoff valve is closed to cut off communication between the intake passage and the exhaust passage through the pressure wave supercharger. As a result, the intake air is drawn into the engine via the intake bypass passage, and the exhaust gas is discharged via the exhaust bypass passage, allowing the engine to intake and exhaust air. It is prevented from flowing into the intake passage through the wave supercharger, thus maintaining engine operation.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

In the figure, 1 is a four-cylinder engine, 2 is an upstream end that opens to the atmosphere, and a downstream end that opens to each cylinder of the engine 1 via branch passages 2a to 2d.
An intake passage 3 that supplies intake air to each cylinder of the engine 1 has an upstream end that opens to each cylinder of the engine 1 via branch passages 3a to 3d, and a downstream end that opens to the atmosphere to discharge exhaust gas from each cylinder of the engine 1. This is the exhaust passage.

4 is disposed across the intake passage 2 and exhaust passage 3, and is driven by the engine 1 to a belt transmission mechanism 5.
This is a pressure wave supercharger that is rotationally driven through the As is well known, the pressure wave supercharger 4 has a rotor rotatably supported within a case, and a large number of partition walls are arranged radially around the outer circumference of the rotor, and the partition walls allow the rotor to A large number of small chambers are formed in the circumferential direction on the outer periphery. An intake inlet 6 and an intake outlet 7 are formed in the case at one end of the rotor. The passages 2 are connected to the downstream side of the pressure wave supercharger 4, respectively. Also,
An exhaust inlet 8 and an exhaust outlet 9 are formed in the case at the other end of the rotor, and communicate with the upstream and downstream sides of the pressure wave supercharger 4 of the exhaust passage 3, respectively. However, as the rotor rotates,
When high-pressure exhaust gas flows into a small chamber in which low-pressure intake air is confined through the exhaust inlet port 8, a pressure wave (compression shock wave) is generated by the pressure difference and propagates inside the small chamber, and the pressure wave energy of the exhaust gas is transferred to the intake air. By being transmitted, the intake air is compressed and accelerated to the intake air outlet 7.
The exhaust gas flowing into the small chamber is then discharged from the exhaust discharge port 9, and the intake air is introduced into the small chamber from the intake inlet port 6 to scavenge the exhaust gas. It is designed to repeat.

Further, 10 is a pressure wave supercharger 4 in the intake passage 2.
This is an air-cooled intercooler installed downstream, and cools the high-temperature intake air supercharged from the pressure wave supercharger 4 by heat exchange with outside air (travel wind). In addition, 11 is a pressure wave supercharger 4 in the intake passage 2.
A coarse first air cleaner is provided upstream, and the air intake inlet 6 of the pressure wave supercharger 4 is communicated with the atmosphere via the first air cleaner 11. A second air cleaner 12 is provided in the intake passage 2 downstream of the pressure wave supercharger 4 and upstream of the intercooler 10, and is finer than the first air cleaner 11. is communicated with the engine 1 via the second air cleaner 12. Furthermore, 13 is an exhaust passage 3
An exhaust surge tank 14 is provided at a meeting point of each of the branch passages 3a to 3d, and a silencer 14 is provided downstream of the pressure wave supercharger 4 in the exhaust passage 3.
Thus, the intake air drawn into the intake passage 2 from the atmosphere is filtered by the coarse first air cleaner 11,
For example, 60 to avoid damaging the pressure wave supercharger 4.
After removing dust of ~80μ or more, the air is sucked into the pressure wave supercharger 4 through the intake air inlet 6, and the pressure wave energy of the exhaust gas is transmitted to the intake air (intake air) in the pressure wave supercharger 4 to reduce the intake air. is pressurized and discharged from the intake/discharge port 7. Next, this pressurized intake air is filtered by a fine-mesh second air cleaner 12, so as not to impede engine performance, for example.
After removing even dust particles of 20 microns or less, the intercooler 10 cools the air to an appropriate temperature and inhales it into each cylinder of the engine 1. After that, the exhaust gas discharged from each cylinder of the engine 1 is suppressed and alleviated in the exhaust pulsation of each cylinder in the exhaust surge tank 13, and then the exhaust gas inlet 8
The air flows into the pressure wave supercharger 4, transmits pressure wave energy to the intake air in the pressure wave supercharger 4, and then flows out from the exhaust outlet 9. After reducing the exhaust noise with the silencer 14, it enters the atmosphere. I'm trying to release it.

As a feature of the present invention, the above-mentioned intake passage 2
, upstream of the pressure wave supercharger 4 (intake inlet 6), downstream of the first air cleaner 11, and pressure wave supercharger 4.
(Intake discharge port 7) downstream and upstream of the second air cleaner 12 are communicated with each other by an intake bypass passage 15 so as to bypass the pressure wave supercharger 4. 1
An intake bypass valve 16 that opens and closes the intake valve 5 is provided. In addition, in the exhaust passage 3, the pressure wave supercharger 4 (exhaust inlet 8) upstream and exhaust surge tank 13 downstream and the pressure wave supercharger 4 (exhaust discharge port 9) downstream and silencer 14 upstream are They are communicated via an exhaust bypass passage 17 so as to bypass the feeder 4, and an exhaust bypass valve 18 for opening and closing the exhaust bypass passage 17 is disposed in the middle of the exhaust bypass passage 17. Further, an exhaust bypass is provided downstream of the upstream end opening of the exhaust bypass passage 17 of the exhaust passage 3 upstream of the pressure wave supercharger 4 (exhaust inlet 8), and downstream of the pressure wave supercharger 4 (exhaust discharge port 9). High-pressure side and low-pressure side cutoff valves 19 and 20 are provided at two locations upstream of the downstream end opening of the passage 17, respectively, for blocking communication between the intake passage 2 and the exhaust passage 3 via the pressure wave supercharger 4. It is arranged.

In addition, 21 is a rotation speed detection means for detecting the rotation speed of the rotor of the pressure wave supercharger 4 or a signal related thereto, and the signal of the rotation speed detection means 21 is inputted to the control means 22. , the control means 22 controls the intake bypass valve 16, the exhaust bypass valve 18, the high pressure side and low pressure side cutoff valves 19,
20 are controlled to open and close, respectively.

That is, the control means 22 is shown in detail in FIG. In the figure, 23 is a first diaphragm device that opens and closes the intake bypass valve 16;
4 is a second diaphragm device that opens and closes the exhaust bypass valve 18; 25 and 26 are third and fourth diaphragm devices that open and close the high-pressure side and low-pressure side cutoff valves 19 and 20. The first diaphragm device 23 includes a diaphragm 23 that supports the intake bypass valve 16 via a link mechanism 23a.
b, a negative pressure chamber 23c and an atmospheric chamber 23d partitioned by the diaphragm 23b, and the negative pressure chamber 2
3c, and a spring 23e that biases the diaphragm 23b in the direction of closing the intake bypass valve 16. When negative pressure is introduced into the negative pressure chamber 23c, the diaphragm 23b is biased by the biasing force of the spring 23e. The air intake bypass valve 16 is biased against the air pressure, thereby opening the intake bypass valve 16. Further, the second diaphragm device 24 includes a diaphragm 24b that supports the exhaust bypass valve 18 via a link mechanism 24a, and a negative pressure chamber 24c and a supercharging pressure chamber 2 that are partitioned by the diaphragm 24b.
4d, and a spring 24c that is compressed in the negative pressure chamber 24c and biases the diaphragm 24b in the direction in which the exhaust bypass valve 18 is closed.When negative pressure is introduced into the negative pressure chamber 24c, the diaphragm 24c 24b is biased against the biasing force of spring 24e to open exhaust bypass valve 18. Although not shown in the above-mentioned supercharging pressure chamber 24d, there is a pressure wave supercharger 4 (intake/discharge port 7).
The pressure (supercharging pressure) in the downstream intake passage 2 is introduced via the supercharging pressure introduction passage 27. Furthermore, the third
Both the fourth diaphragm devices 25 and 26 connect the cutoff valves 19 and 20 to the link mechanisms 25a and 26.
Diaphragms 25b, 26b supported via a
and negative pressure chambers 25c, 26c and atmospheric chamber 25 partitioned by the diaphragms 25b, 26b.
d, 26d, and the diaphragms 25b, 26b compressed in the negative pressure chambers 25c, 26c are connected to the cutoff valve 1.
A spring 25 that biases 9 and 20 in the opening direction.
e, 26e, and the negative pressure chambers 25c,
When negative pressure is introduced into 26c, the diaphragms 25b, 26b are biased against the biasing forces of springs 25e, 26e, and the shutoff valves 19, 20 are closed. Negative pressure chambers 23c to 26c of each of the diaphragm devices 23 to 26
is connected to the vacuum pump 33 via the first to fourth negative pressure introduction passages 28 to 31 and a collective negative pressure introduction passage 32 where these passages are gathered, and the part of the collective negative pressure introduction passage 32 is opened to the atmosphere. The passage 34 is branched, and at this branch part, the negative pressure chambers 23c to 26c are opened to the atmosphere when the OFF operation is normally performed, and the negative pressure chambers 23c to 26c are opened to the atmosphere when the OFF operation is performed.
A three-way valve 3 that communicates ~26c with the vacuum pump 33
5 is interposed. The three-way valve 35 includes a control unit 36 comprising a CPU that receives the signal from the rotation speed detection means 21 and outputs a lock signal (ON signal) when the rotation speed of the rotor is below a set value (approximately zero). is connected to the control unit 36, and an indicator lamp 37 that lights up upon receiving a lock signal from the control unit 36 is further connected to the control unit 36. However,
Under normal conditions, the control unit 36
The three-way valve 35 is in the OFF state due to the OFF signal, and the negative pressure chambers 23c of each diaphragm device 23 to 26 are
26c is open to the atmosphere, the diaphragm devices 23 to 26 are not operated, the intake bypass valve 16 and the exhaust bypass valve 18 are closed, and the high-pressure side and low-pressure side cutoff valves 19 and 20 are open.
On the other hand, when the rotation of the rotor of the pressure wave supercharger 4 is locked, the three-way valve 35 is turned ON by the lock signal (ON signal) from the control unit 36.
By operating and introducing negative pressure from the vacuum pump 33 into the negative pressure chambers 23c to 26c of each diaphragm device 23 to 26, each diaphragm device 23
26 are configured to operate to open the intake bypass valve 16 and the exhaust bypass valve 18 and close the high-pressure side and low-pressure side cutoff valves 19 and 20. When the rotor is locked, the ON signal is continuously output, and the bypass valves 16 and 18 are kept open and the cutoff valves 19 and 20 are kept closed, but when the engine is stopped, the output of this ON signal is reset. Although it is in the OFF state, an ON signal is output immediately when the engine is restarted. For this reason, unless the locking condition of the rotor is repaired,
Bypass valves 16 and 18 are closed when the engine is running;
Shutoff valves 19 and 20 do not open. The second diaphragm device 24 also includes a supercharging pressure chamber 24.
When the supercharging pressure introduced into d exceeds the set value, the diaphragm 24b similarly biases against the biasing force of the spring 24e and opens the exhaust bypass valve 18, thereby removing the exhaust gas upstream of the pressure wave supercharger 4. Bypass flowing downstream of the pressure wave supercharger 4 via the exhaust bypass passage 17 without flowing into the pressure wave supercharger 4,
This reduces the supercharging pressure and holds it at the maximum set supercharging pressure value, thereby providing a wastegate valve function that prevents damage to the engine 1 due to an abnormal increase in the supercharging pressure.

Therefore, in the embodiment described above, when the pressure wave supercharger 4 is locked and the rotation of the rotor is stopped due to the intrusion of foreign matter, the control means 22 opens the intake bypass valve 16 and the exhaust bypass valve 18, and the high pressure side and the low pressure side are opened. By closing the side shutoff valves 19 and 20, intake air passes through the intake bypass passage 15, bypasses the pressure wave supercharger 4, and is taken into the engine 1, and exhaust air from the engine 1 passes through the exhaust bypass passage 17. The air is discharged bypassing the pressure wave supercharger 4, and the intake and exhaust of the engine 1 is ensured.
Moreover, the attempt of exhaust gas to flow into the intake passage 2 via the pressure wave supercharger 4 due to the pressure difference between the exhaust passage 3 and the intake passage 2 is prevented by the shutoff of the above-mentioned shutoff valves 19 and 20. Therefore, the operation of the engine 1 is maintained well, and running performance can be ensured even when the pressure wave supercharger 4 is locked.

Further, in the above embodiment, the cutoff valves 19 and 20 for blocking communication between the intake passage 2 and the exhaust passage 3 via the pressure wave supercharger 4 are provided on the exhaust passage 3 side from the pressure wave supercharger 4. This has the advantage that when the pressure wave supercharger 4 is locked, even if the pressure wave supercharger 4 is damaged, exhaust gas can be prevented from leaking from the damaged location.

In the above embodiment, the cutoff valves 19 and 20 are provided on the exhaust passage 3 side from the pressure wave supercharger 4, but they may be provided on the intake passage 2 side. However, in order to prevent exhaust gas from leaking from a damaged part of the pressure wave supercharger 4, it is preferable to provide it on the exhaust passage 3 side as described above.

Further, in the above embodiment, the high pressure side and low pressure side shutoff valves 19 and 20 are each provided with separate diaphragm devices 2.
5 and 26, but it goes without saying that the opening and closing operations may be performed in conjunction with one diaphragm device.

(Effects of the Invention) As explained above, according to the pressure wave supercharged engine of the present invention, when the pressure wave supercharger is locked, the intake bypass passage for intake air and the exhaust bypass passage for exhaust air flow through the intake bypass passage. Since the exhaust gas is prevented from flowing into the intake passage through the pressure wave supercharger, engine operation can be maintained and at least driving performance can be ensured. can.

[Brief explanation of the drawing]

FIG. 1 is an overall schematic diagram showing an embodiment of the present invention, and FIG. 2 is a detailed diagram of the main part of FIG. 1. 1... Engine, 2... Intake passage, 3... Exhaust passage, 4... Pressure wave supercharger, 6... Intake inlet,
7... Intake discharge port, 8... Exhaust inlet port, 9... Exhaust discharge port, 15... Intake bypass passage, 16...
Intake bypass valve, 17...Exhaust bypass passage, 1
8...Exhaust bypass valve, 19,20...Shutoff valve,
21... Rotation speed detection means, 22... Control means.

Claims (1)

[Scope of utility model registration request] A rotor that is rotatably supported within a case and has a number of radially arranged partition walls forming a number of small chambers, an intake inlet and an intake outlet formed in the case at one end of the rotor, and the rotor. A pressure wave supercharger has an exhaust inlet and an exhaust outlet formed in the case at the other end, and supercharges the intake by transmitting the pressure wave energy of the exhaust to the intake as the rotor rotates. In the supercharged engine, an intake bypass passage connects an intake passage upstream of the intake inlet and an intake passage downstream of the intake discharge port, bypassing the supercharger, and opening and closing the intake bypass passage. an intake bypass valve; an exhaust bypass passage that connects an exhaust passage upstream of the exhaust inlet and an exhaust passage downstream of the exhaust discharge port by bypassing the supercharger; and an exhaust bypass valve that opens and closes the exhaust bypass passage. , a shutoff valve that cuts off communication between the intake passage and the exhaust passage through the supercharger, a rotation speed detection means for detecting a signal related to the rotation speed of the rotor, and a signal from the rotation speed detection means. 1. A supercharged engine, comprising control means that opens the intake bypass valve and the exhaust bypass valve and closes the cutoff valve when a locked state of the rotor is detected.