JPH0128244Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a lubricating oil supply device for a rotary piston engine equipped with a catalyst device for purifying exhaust gas in the exhaust passage, and is particularly suitable for use during engine deceleration operation or reduced cylinder operation. The present invention relates to measures against poisoning of the catalyst device by lubricating oil in a rotary piston engine in which the supply of fuel is cut off during specific operations such as at certain times of the day.

(Prior art) Generally, in rotary piston engines,
In order to lubricate the rotor that rotates planetarily within the casing and the inner wall surface of the casing, there is a system that supplies lubricating oil to the working chamber, separate from the main lubrication system that circulates through the engine body. The amount of lubricating oil supplied to the working chamber is normally set to the sum of the amount of oil required for lubrication within the casing and the amount of oil burned within the working chamber.

By the way, conventionally, as a lubricating oil supply device for such a rotary piston engine, for example,
As shown in Publication No. 56-6003, a metering oil pump is provided with a first lubricant supply passage that opens into the intake passage and a second lubricant supply passage that opens directly from the rotor housing to the working chamber. A so-called two-path oil supply system is known in which lubricating oil from the engine is supplied to the working chamber via the intake passage or directly by a first or second lubricating oil supply passage.

In the oil supply path of the first lubricating oil supply passage that opens into the intake passage, the lubricating oil mixes with the intake air flowing through the intake passage, is sufficiently diffused, and then flows into the intake working chamber, so that the lubricating oil spreads over the entire intake working chamber. The lubricant is distributed almost uniformly and evenly lubricates the rotor and the inner wall surface of the casing. On the other hand, in the oil supply path through the second lubricating oil supply passage that opens directly from the rotor housing to the working chamber, lubricating oil is unevenly distributed on the inner circumferential surface of the rotor housing in the working chamber, and the inner circumference of the rotor housing requires strict lubricity. It intensively lubricates the surface and apex seal, and they complement each other.

On the other hand, recently, in rotary piston engines, in order to improve fuel efficiency and emission performance, the supply of fuel to the working chambers has been cut off during specific operations such as when the engine is decelerating or when the cylinders are being reduced. ing.

However, when the fuel supply is cut like this,
Since fuel is not supplied within the working chamber, an excess amount of lubricating oil is supplied to the working chamber corresponding to the amount burned within the working chamber as described above. In that case, as described above, in the oil supply path using the second lubricating oil supply passage that opens directly into the working chamber, the lubricating oil is unevenly distributed on the inner circumferential surface of the rotor housing in the intake working chamber, and the temperature of the inner circumferential surface of the rotor housing is Since the amount of lubricating oil is relatively low, the above-mentioned extra amount of lubricating oil is discharged as it is without being burned while containing organic phosphorus, and it adheres to the catalyst of the exhaust purification catalyst device installed in the exhaust passage, and the catalyst There is a problem that it is poisoned and deteriorates. On the other hand, in the oil supply line with the first lubricant supply passage that opens into the intake passage, the lubricant is distributed almost uniformly throughout the intake working chamber, and the rotor, etc. is maintained at a relatively high temperature even when the fuel supply is cut. Therefore, most of the excess lubricating oil is burned, and the presence or absence of phosphorus contained in the lubricating oil becomes mineralized and becomes a state containing a large amount of inorganic phosphorus. Therefore, even if it is discharged into the exhaust passage, it is not exposed to the catalyst as described above. There isn't much of a poison problem.

(Purpose of the invention) In view of the above, the purpose of the invention is to supply lubricating oil to the working chamber only through the oil supply system path, which is the first lubricating oil supply passage that opens into the intake passage when the fuel supply is cut. Another object of the present invention is to suppress or reduce poisoning of a catalyst in a catalyst device disposed in an exhaust passage, prevent deterioration of the catalyst, and improve its durability.

(Structure of the invention) In order to achieve the above object, the technical solution of the invention is to provide a catalyst device for exhaust purification in the exhaust passage of the engine, and to supply lubricating oil from the metering oil pump to the intake passage. The lubricating oil is supplied to the working chamber through at least one of the first lubricating oil supply passage that opens into the working chamber and the second lubricating oil supply passage that opens into the working chamber, and also to the working chamber during specific operations such as engine deceleration or reduced cylinder operation. The rotary piston engine is configured to cut off the fuel supply, and is provided with a control device that controls the lubricating oil to be supplied only from the first lubricating oil supply passage when the fuel supply is cut off.

As a result, when the fuel supply is cut, the lubricating oil is supplied to the intake passage only from the first lubricating oil supply passage under the control of the control device, mixed with the intake air flowing through the intake passage and sufficiently diffused, and then The lubricating oil is distributed almost uniformly throughout the intake working chamber, and the excess lubricating oil from the fuel supply cut is combusted by the heat of the rotor, which is maintained at a relatively high temperature. It was designed to let you do so.

(Effect of the invention) Therefore, according to the invention, in a rotary piston engine in which the supply of fuel to the working chamber is cut during specific operations such as engine deceleration or reduced cylinder operation, the fuel supply is cut. At the time, the lubricating oil from the metering oil pump was supplied to the working chamber through the intake passage, so the excess lubricating oil from the fuel supply cut was almost completely burned and discharged into the exhaust passage while still containing organic phosphorus. Therefore, poisoning of the catalyst of the catalyst device in the exhaust passage can be suppressed or reduced, and deterioration of the catalyst can be prevented and its durability can be improved.

(Example) Hereinafter, an example as a specific example of the technical means of the present invention will be described based on the drawings.

In FIG. 1, 1 is a multi-arc inner peripheral surface 2a.
A casing 4 is a polygonal rotor that is supported by an eccentric shaft 5 and rotates planetarily within the casing 1, and is composed of a rotor housing 2 having a rotor housing 2 and side housings 3, 3 disposed at both ends of the rotor housing 2. As the rotor 4 rotates, the inside of the casing 1 is divided into three working chambers 6, 6, 6,
It is configured to sequentially perform compression, explosion, expansion, and exhaust strokes. In addition, 7 is an apex seal attached to each top of the rotor 4, and 8 is the rotor 4.
9 is the side seal attached to the side of the rotor 4.
Corner seals attached to both sides of each top, 10
and 11 are leading side and trailing side spark plugs, respectively.

Further, the upstream end of 12 is open to the atmosphere via the air cleaner 13, and the downstream end is open to the side housing 3.
This is an intake passage that opens into the working chamber 6 and supplies intake air to the working chamber 6 through an intake port 14 provided in the intake passage. Throttle valves 16 for controlling the amount of intake air are arranged downstream of the air flow meters 15, respectively. Further, a fuel injection valve 17 for injecting fuel is arranged in the vicinity of the intake port 14 of the intake passage 12. Note that 18 is an exhaust port provided in the rotor housing 2, 19 is an intake passage connected to the exhaust port 18, and 20 is a catalyst device for exhaust purification that is interposed in the exhaust passage 19.

On the other hand, 21 is a metering oil pump that measures and pressure-feeds lubricating oil according to the engine speed and load, and the metering oil pump 21 has first and second lubricating oil supply passages 22 and 23. The first lubricating oil supply passage 22 is connected to the intake passage 1.
The lubricating oil injected from the first oil supply nozzle 24 is supplied to the working chamber 6 through the intake passage 12. Therefore, it mainly contributes to the lubrication of the inner circumferential surface 2a of the rotor housing 2 and the side seal 8. The second lubricating oil supply passage 23 opens directly into the working chamber 6 via a second lubricating nozzle 25 provided in the rotor housing 2, and the lubricating oil injected from the second lubricating nozzle 25 is supplied to the working chamber 6. It is designed to mainly contribute to the lubrication of the apex seal 7 and the inner circumferential surface 2a of the rotor housing. Furthermore, since the second oil supply nozzle 25 opens directly into the working chamber 6, the lubricating oil may be scattered due to the influence of the pressure inside the working chamber 6. Therefore, the apex seal 7 may not open during normal operation of the engine. When passing directly under the second refueling nozzle 25, the front and rear working chambers 6, which are partitioned by the apex seal 7,
It is preferable to provide the pressure at a position where the pressures of the two pressures are approximately equal.

Reference numeral 26 denotes an on-off valve which is interposed in the middle of the second lubricating oil supply passage 23 and controls opening and closing of the second lubricating oil supply passage 23 . Further, 27 is an engine load sensor that detects the engine load condition based on the opening degree of the throttle valve 16, and 28 is an engine rotation speed sensor that detects the engine rotation speed based on the ignition pulse.The outputs of both sensors 27 and 28 are is input to a control circuit 29, and the fuel injection valve 17 and the on-off valve 26 are connected to the control circuit 29 to control the operation of each.

That is, as shown in FIG. 2, the control circuit 29 includes an engine load detection circuit 30 that receives an output from the engine load sensor 27 and issues an engine load signal, and an engine load detection circuit 30 that receives an output from the engine speed sensor 28 and detects the engine speed. An engine rotation speed detection circuit 31 that emits a number signal, and receives an engine load signal from the engine load detection circuit 30 and an engine rotation speed signal from the engine rotation speed detection circuit 31 during engine deceleration operation, reduced cylinder operation, etc. , a fuel cut zone determination circuit 3 that determines the operating range in which fuel supply should be cut and outputs a fuel cut signal;
2, a fuel injector drive circuit 33 that receives a fuel cut signal from the fuel cut zone determination circuit 32 and stops the operation of the fuel injection valve 17; The on-off valve drive circuit 34 closes the on-off valve 26, and cuts off the supply of fuel by the fuel injection valve 17 during a specific operation such as deceleration operation or cylinder reduction operation, and also closes the on-off valve 26 to close the on-off valve 26. A control device 35 is configured to close the lubricating oil supply passage 23 and supply lubricating oil only from the first lubricating oil supply passage 22.

Next, the operation of the above embodiment will be described. During normal operation of the engine, the fuel injection valve 17 is in a normal operating state due to the inoperation of the control circuit 29, and the air flow meter 14 is connected to the fuel injection valve 17.
An amount of fuel corresponding to the output (amount of intake air) is injected into the intake passage 12 and supplied to the working chamber 6, ensuring good fuel quality in the working chamber 6. In addition, the on-off valve 26 is in an open state due to the inoperation of the control circuit 29, and the second lubricating oil supply passage 23 is open, and the metering oil pump 21 is used to adjust the speed according to the engine speed and load. The measured lubricant is the first
The gas is injected from the first and second oil supply nozzles 24 and 25 via the second lubricant supply passages 22 and 23 and is supplied to the working chamber 6 through the intake passage 12 or directly, thereby causing the gas mounted on the rotor 4 to Seal members (apex seal 7, side seal 8
etc.) and the inner wall surface of the casing 1, and a portion of the lubrication is consumed by the fuel.

On the other hand, during specific operations such as engine deceleration or cylinder operation, the control circuit 29 operates to stop the fuel injection valve 17 and cut off the fuel supply, and the on-off valve 26 closes. The second lubricating oil supply passage 23 is then closed. As a result, the lubricating oil from the metering oil pump 21 is supplied only from the first lubricating oil supply passage 22. At this time, the lubricating oil injected into the intake passage 12 from the first oil supply nozzle 24 mixes with the intake air flowing through the intake passage 12 and is sufficiently diffused before being sucked into the intake working chamber 6. It is distributed almost uniformly throughout 6. Therefore, the excess amount of lubricating oil that is not being combusted by the fuel supply cut is almost combusted by the heat of the rotor, etc., which is maintained at a relatively high temperature even during the fuel supply cut, and Most of the organic phosphorus contained in the lubricating oil is also mineralized. As a result, even if the catalyst is discharged into the exhaust passage 19, it is possible to suppress or reduce poisoning of the catalyst of the catalyst device 20, thereby preventing deterioration of the catalyst and improving its durability.

It should be noted that the present invention is not limited to the above-mentioned embodiments, but also includes various other modifications. For example, in the above embodiment, the first and second lubricating oil supply passages 22 and 23 are provided, and lubricating oil is supplied from both lubricating oil supply passages 22 and 23 during normal operation of the engine, and when the fuel supply is cut, the lubricating oil is supplied from the first and second lubricating oil supply passages 22 and 23. The lubricating oil supply passage 23 is closed and lubricating oil is supplied only from the first lubricating oil supply passage 22, but instead, during normal operation, lubricating oil is supplied only from the second lubricating oil supply passage 23, and when fuel supply is cut, lubricating oil is supplied from the second lubricating oil supply passage 23. Switching control may be performed so that the lubricating oil is supplied only from one lubricating oil supply passage 22. Furthermore, when the fuel supply is cut, the lubricating oil from the second lubricating oil supply passage 23 may be merged into the first lubricating oil supply passage 22 so that the lubricating oil is supplied only from the first lubricating oil supply passage 22. In short,
Metering oil pump 21 when fuel supply is cut
The lubricating oil from the first lubricating oil supply passage 22 , that is, the lubricating oil supply passage 22 opening into the intake passage 12 may be supplied to the working chamber 6 via the intake passage 12 .

[Brief explanation of drawings]

The drawings illustrate an embodiment of the present invention, with FIG. 1 being a general schematic diagram and FIG. 2 being a block diagram of a control circuit. 1...Casing, 2...Rotor housing,
6... Working chamber, 12... Intake passage, 17... Fuel injection valve, 19... Exhaust passage, 20... Catalyst device,
21...Metering oil pump, 22...1st
Lubricating oil supply passage, 22... second lubricating oil supply passage,
26...Opening/closing valve, 27...Engine load sensor,
28... Engine rotation speed sensor, 29... Control circuit, 35... Control device.

Claims (1)

[Scope of utility model registration request] A catalyst device for exhaust purification is provided in the exhaust passage of the engine, and lubricating oil from the metering oil pump is supplied to at least one of the first lubricating oil supply passage opening into the intake passage and the second lubricating oil supply passage opening opening into the working chamber. While supplying the working chamber through one side,
In a rotary piston engine that cuts off the supply of fuel to the working chamber during a specific operation of the engine, a control device is provided that controls the supply of lubricating oil only from the first lubricating oil supply passage when the fuel supply is cut off. A lubricating oil supply device for a rotary piston engine, characterized in that: