JPS5851201A - Lubricant oil supply device in rotary piston engine with supercharger - Google Patents

Abstract

PURPOSE:To provide a proper lubrication by a method wherein a plurality of passages for supplying lubricant oil to the operating chamber of an engine are arranged for each of the cylinders, while the lubricant oil is supplied from a passage when a supercharging pressure is less than a desired value and in turn lubricant oil is supplied from all the passages when the supercharging pressure is higher than the desired value. CONSTITUTION:Rotary piston engine 1 is provided with a supercharger 11 comprising a turbine 12 arranged in an exhaust passage 9, a blower 13 arranged in the intake passage 8 and a shaft 14 connecting these component elements. With the above arrangement, the first lubricant oil passage 21 opened to an intake manihold of the intake passage 8 and the second lubricant oil passage 22 directly opened to the operating chamber 5 of the engine 1 are arranged, and the passage 22 is provided with a control valve 23 which is opened when a supercharging pressure is higher than the desired value. When the supercharger 11 is in a non-loaded condition or in a low supercharging condition, the lubricant oil in the oil pan 25 is fed only from the passage 21 to the intake passage 8 and the operating chamber 5, and when the supercharging pressure is higher than the desired value, the lubricant oil is supplied from both passages 21, 22 to the operating chamber 5.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lubricating oil supply device for a turbocharged rotary piston engine.

Generally, in a rotary piston engine, in order to lubricate the parts such as apex seals installed on the rotor that come in sliding contact with the inner surface of the casing, a lubricating oil passage is opened into the intake passage or directly into the working chamber of the engine. ．． It supplies lubricating oil to the working chamber of the engine. Conventional lubricating oil supply devices for rotary piston engines of this type often include a single intake passage per cylinder. By the way, in a rotary piston engine equipped with a supercharger to improve engine combustibility through intake supercharging, the higher the supercharging (1:), the more lubricating oil is required, but conventional lubricating oil According to the supply bag@, there was no proper control of the lubricant Ni supply amount according to the boost pressure.For this reason, it was not necessary at low boost.
If lubricating oil is supplied to the engine, a large amount of lubricating oil will be consumed and it will be uneconomical.''Secondly, the spark plug will get stained with lubricating oil and cause a misfire, and if there is a shortage of lubricating oil during high supercharging. There were problems such as impairing the sealing performance between the apex seal and the inner surface of the casing, and causing wear and damage to the apex seal and the like.

In addition, recently, as seen in Japanese Unexamined Patent Publication No. 56-003, when the apex seal vibrates due to poor lubrication at the sliding contact area between the apex seal of the rotor and the inner surface of the casing, the vibration is detected and A lubricating oil supply device has been developed that includes a control means for increasing the amount of lubricating oil supplied based on the amount of lubricating oil supplied. However, this control means adjusts the lubricant supply amount only after a lubricant supply shortage actually occurs, which delays response and does not prevent adverse effects such as apex seal wear. There wasn't.

In view of these circumstances, the present invention provides a rotary piston engine with a supercharger, by providing a plurality of lubricating oil passages per cylinder and appropriately controlling the lubricating oil supply by these passages according to the supercharging pressure. It is possible to prevent the above-mentioned problems such as misfire due to plug wetting during low supercharging and wear of the apex seal due to lack of lubrication during high supercharging.Embodiments of the present invention will be described below with reference to the drawings. .

Reference numeral 1 denotes a casing of a rotary piston engine, which is composed of a rotor housing 2 having a trochoidal inner peripheral surface and a side housing 6. The casing 1 is provided with a substantially king-shaped rotor 4 that rotates planetarily, and a working chamber 5 is defined between the inner surface of the casing 1 and the rotor 4. ” - At the top of the rotor 4 there is an apex seal 6.
. . . are equipped with Kohli seals (not shown) on both sides, and these slide into contact with the inner surface of the rotor housing 2 and the inner surface of the side housing 6 (C), thereby sealing the working chamber 4 . Airtightness is maintained.Furthermore, spark plugs 7 are installed at predetermined positions in the rotor housing 2. 8 is one intake passage, and 9 is an exhaust passage, each having 11 predetermined positions. It opens into the casing 1 at.] - Outside air is introduced into the intake passage 8 through an air creaser 10, and fuel is supplied from a fuel supply device (not shown).

In addition, 11 is a supercharger, and the illustrated example shows a turbo supercharger.
The turbine 12 provided in the exhaust passage 9 and the intake passage 8
A blower 16 provided therein and a shaft 14 that interlocks and connects these allow the blower 13 to rotate as the turbine 12 is rotated by the exhaust gas flow, thereby performing intake supercharging.

Note that 15 is a variable pressure chamber connected to the blower 1 through a communication path 16.
A diaphragm device 17 communicates with the intake passage 8 downstream from 3, a bypass passage 17 is attached to the exhaust passage 9 bypassing the turbine 12, and 18 is operated by the diaphragm device 15 to open and close the bypass passage 17. These are bypass control valves that reduce the required boost pressure by letting some of the exhaust gas escape into the bypass passage and suppressing the turbocharger driving force when the boost pressure reaches the highest limit of the required range. This is to control the temperature so that it does not rise above this level.

In such a rotary piston engine with a supercharger, the present invention provides a lubricating oil passage for supplying lubricating oil into the working chamber through a plurality of passages per cylinder, and when the supercharging pressure is below a predetermined value, one lubricating oil passage is provided. The control mechanism is provided for supplying lubricating oil from one lubricating oil passage and from all lubricating oil passages when the boost pressure is higher than a predetermined value. In particular, in this embodiment, a first lubricating oil passage 21 that opens into the intake manifold of the intake passage 8 and a second lubricating oil passage 22 that opens directly into the working chamber 5 of the engine are provided. A control valve 23 is provided that opens when the boost pressure is at a predetermined level -■-. The first lubricating oil passage 21 is connected to an oil pump 25 via a metering oil pump 24. The second lubricating oil passage 22 is connected to a branch passage 26 branched from the first lubricating oil passage 21 via the control valve 23 .

The control valve 26 closes the second lubricating oil passage 22 and communicates the second branch passage 26 with the return passage 27;
The second lubricating oil passage 22 can be opened and opened so as to communicate with the branch passage 26.

As a means for operating the control valve 26 according to the boost pressure, in the illustrated example, the control valve 23 is provided with a pressure chamber 28 for pushing the valve, and the pressure chamber 28 is connected to the boost pressure introduction passage 29.
It is communicated with the intake passage 8 downstream of the blower 16 of the supercharger 11 via. When the supercharging pressure introduced from the intake passage 8 into the pressure chamber 28 reaches a predetermined value or higher, the control valve 26 is pushed by the pressure to open the second lubricating oil path 22. It is configured as follows.

The amount of lubricating oil supplied from the first lubricating oil passage 21 and the second lubricating oil passage 22 and the predetermined supercharging pressure for switching and operating the control valve 26 are set in advance to meet the requirements.

The operation of this lubricating oil supply device will be explained below.

First, when the engine speed is low and the supercharger 11 is in a non-supercharging or low supercharging state, the control valve 26 closes the second lubricating oil passage 22.

At this time, the lubricating oil is sent into the intake passage 8 only from the first lubricating oil passage 21, and together with the air-fuel mixture, the lubricating oil is fed into the working chamber 5 of the engine.
sent to. As a result, at low speeds and low supercharging that do not require a large amount of lubricant, the lubricant supply amount is suppressed to the necessary limit, and the 33 engine rotational speed is increased to prevent wetting of the spark plug 7 by lubricant. When the boost pressure reaches a predetermined value -J-, the control valve 23 is activated to open the second lubricating oil passage 22, and both the first and second warm oil passages 2 are opened.
Lubricating oil is supplied to the working chamber 5 of the engine from 1.22. This increases the amount of lubricating oil supplied and maintains good lubricity even during high supercharging.

In other words, at high speeds and high supercharging, wetting of the plug 7 due to lubricating oil is not a problem, but a large amount of lubricating oil is required at the sliding contact area between the apex seal 6, etc. and the inner surface of the casing 1. , such requirements can be satisfied by increasing the amount of lubricating oil supplied as described above.

In particular, as in the illustrated embodiment, the first lubricating oil passage 21, which is open even during low supercharging, is opened to the 1 m intake path 8, and the second lubricating oil passage 22, which is open only during high supercharging, is connected to the working chamber of the engine. 5
If it is opened to 1], even better supercharging pressure control conditions can be obtained. That is, in general, direct lubrication in which the lubricating oil passage is opened directly into the working chamber of the engine provides good lubrication efficiency for the inner circumferential surface of the rotor housing 2, but on the other hand, the plug tends to get wet, and the lubricating oil Inhale the aisle 1
Manifold oil supply that opens into the air manifold reduces wetting of the plug, but there is a tendency for the lubricating oil to mix with the air-fuel mixture and burn, resulting in poor lubrication efficiency.

Therefore, as in this example, manifold lubrication is used to supply lubricating oil during low turbocharging, where plug wetting is a problem, and direct lubrication is used to supply the increased amount of lubricating oil at high turbocharging, where lubricity is a problem. If this is done, along with the adjustment of the lubricant supply amount, suitable lubrication conditions can be obtained depending on the boost pressure.

Note that six or more lubricating oil passages may be provided per cylinder and these passages may be controlled according to the boost pressure, but normally the first lubricating oil passage. It is sufficient to control the lubricating oil supply amount using the second passages '21 and 23. Further, each lubricating oil passage may be opened to the intake passage or to the working chamber of the engine, but as mentioned above, it is preferable that each lubricating oil passage 21 and 22 are connected to the intake passage and the working chamber of the engine. Leave each one open.

In addition, in a supercharged engine, supercharging pressure has a proportional relationship with back pressure, engine speed, engine load, etc., so instead of directly operating the control valve 23 with supercharging pressure, The opening of the lubricating oil passage may be controlled indirectly in accordance with the boost pressure by a mechanical or electrical control means using control signals such as the back pressure of the engine, the engine speed, and the engine load.

As explained above, according to the device of the present invention, a rotary piston engine with a supercharger has a plurality of lubricating oil passages per cylinder and a control mechanism that controls these passages according to the boost pressure, so that no overflow can be achieved. During high or low supercharging, the lubricating oil supply amount can be suppressed to the extent that the plug does not get wet, and during high supercharging, the lubricating oil supply amount can be increased to the extent that no adverse effects due to lack of lubrication occur. It is possible to provide a good supply of lubricating oil that is suitable for the corresponding operating conditions.

[Brief explanation of drawings]

The figure is a schematic diagram showing an embodiment of the tree invention device. 1.-Rotary piston engine casing, 4.
- Rotor, 5 Working chamber, 11... Supercharger, 21... First lubricating oil passage, 22... Second? lAi i'i')
Oil passage, 23...=10- control valve. Patent applicant: Toyo Kogyo Co., Ltd. “f, ff1A +TfJi”:
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Claims (1)

[Claims] t In a supercharged rotary piston engine, 1
A plurality of lubricating oil passages are provided for each cylinder to supply lubricating oil into the working chamber, and when the boost pressure is below a certain level, some of the lubricating oil passages are used, and when the boost pressure is above a certain level, all the lubricating oil passages are used. A lubricating oil supply device for a rotary piston engine with a supercharger, which is equipped with a control mechanism that supplies lubricating oil from a rotary piston engine. 2. In claim 1, the lubricating oil passage is constituted by a first lubricating oil passage that opens to the intake passage and a second lubricating oil passage that opens to the working chamber of the engine, and the second lubricating oil passage includes: A lubricating oil supply device for a rotary piston engine with a supercharger, characterized in that it is provided with a valve that opens when supercharging pressure is higher than a predetermined value.