JPH05231120A - Lubricator for engine with supercharger - Google Patents

Abstract

(57) [Summary] [Purpose] It is possible to supply lubricating oil at a pressure lower than the required hydraulic pressure to the sliding parts of the engine while ensuring the required hydraulic pressure in the low engine speed range. , In the same area, reduce the sliding resistance. In an engine provided with a supercharger 31 for compressing and compressing intake air, at least sliding parts 20, 2 of the engine
First lubrication path 12 for supplying lubricating oil to
Supply oil pressure varying means 28 that is provided upstream of the lubrication passage 12 and that can set the oil pressure of the first lubrication passage 12 to a pressure lower than the supply oil pressure to the supercharger 31 in the low rotation region of the engine.
And a second lubricating path 33 that is provided independently of the first lubricating path 12 and supplies lubricating oil to the sliding portion of the supercharger 31 via the oil cooler 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubricating device for an engine with a supercharger for supplying lubricating oil to sliding parts of an engine and a sliding part of a supercharger.

[0002]

2. Description of the Related Art Conventionally, as a lubricating device for an engine provided with a supercharger as described above, for example, the actual engine 61-1644.
There are devices described in Japanese Patent No. 101 and Japanese Utility Model Laid-Open No. 61-169213.

That is to say, the former case, Shokai 61-16441
The lubricating device described in Japanese Patent Publication No. 01-101 discloses an oil discharge line of an oil pump, for example, one lubrication route for lubricating a crank bearing portion via a conduit, and an oil conduit branched from the discharge line of the oil pump described above. This is a two-system lubrication device with the other lubrication path that lubricates the turbocharger via the cooler.

However, this conventional apparatus has the following problems because it has no means for controlling the pressure of the lubricating oil in the above-mentioned one lubricating path and the other lubricating path. In other words, when the engine speed is low, you want to reduce the hydraulic pressure supplied to the engine bearings to improve fuel efficiency,
One lubrication path that supplies lubricating oil to the engine bearing part,
The pressure of the lubricating oil in the other lubricating path that supplies the lubricating oil to the turbocharger is approximately the same, and the required hydraulic pressure of this turbocharger is, for example, 2 kg / cm ² , so when the engine is running at low speeds. Even in the above, the pressure of the lubricating oil supplied to the engine bearing cannot be reduced to about 2 kg / cm ² or less.

Therefore, it is necessary to set the discharge pressure of the oil pump to be equal to or higher than the required hydraulic pressure of the turbocharger when the engine is running at a low speed, and it is impossible to reduce the hydraulic pressure of the crank bearing portion in the fuel consumption improvement region. Is large, and the temperature of the bearing is lowered by the oil pressure supplied by the lubricating oil, the oil viscosity is improved, and the sliding resistance is large.
There was a problem that the engine load increased.

In the latter lubrication device disclosed in Japanese Utility Model Laid-Open No. 61-169213, one oil path for lubricating a sliding portion on the engine body side through an oil conduit in an oil pump discharge line, and the above-mentioned lubrication device are used. This is a two-system lubrication device in which an oil conduit branched from a discharge line of an oil pump is provided with another oil path for lubricating a turbocharger via an oil cooler, and a throttle is provided downstream of the oil cooler.

According to this lubricating device, since the throttle is provided upstream of the turbocharger, the other oil path upstream of the throttle and the one oil path are set to have a higher pressure than the turbocharger required hydraulic pressure. Set and set the hydraulic pressure supplied to the turbocharger to the turbocharger required hydraulic pressure by the above-mentioned throttle to secure the required hydraulic pressure to the turbocharger at the time of high engine speed, while ensuring sufficient sliding parts on the engine body side. It has the advantage that it can be lubricated,
When the pressure of the lubricating oil supplied to the sliding parts on the engine body side is reduced at low engine speed, the hydraulic pressure supplied to the turbocharger behind the throttle will be less than the required hydraulic pressure. In the above, the hydraulic pressure supplied to the sliding portion on the engine main body side could not be lowered below the turbocharger required hydraulic pressure, and there was the same problem as described above.

[0008]

The invention according to claim 1 of the present invention secures the supercharger required hydraulic pressure in a low engine speed region, and at the same time, the supercharger required hydraulic pressure is applied to the sliding portion of the engine. It is an object of the present invention to provide a lubricating device for a supercharged engine that can supply low-pressure lubricating oil and can reduce sliding resistance in the same region.

The invention according to claim 2 of the present invention, together with the object of the invention according to claim 1, secures the supercharger required hydraulic pressure in the low engine speed low load region (that is, the fuel efficiency improving region). Provide a lubricating device for a supercharged engine that can supply lubricating oil at a pressure lower than the required hydraulic pressure to the sliding parts of the engine and reduce sliding resistance in the same region. With the goal.

According to a third aspect of the present invention, in addition to the object of the first or second aspect of the invention, in the output region of the engine, the pressure higher than the supercharger required hydraulic pressure is applied to the sliding portion of the engine. It is an object of the present invention to provide a lubrication device for an engine with a supercharger, which is capable of supplying sufficient lubricating oil to perform sufficient lubrication.

According to the invention of claim 4 of the present invention, in addition to the object of the invention of claim 1, 2 or 3, the combustion chamber wall can be efficiently lubricated and cooled particularly in the output region of the engine. An object of the present invention is to provide a lubricating device for a supercharged engine that can prevent knocking.

According to the invention of claim 5 of the present invention, in addition to the object of the invention of claim 4, a throttle is provided at a predetermined portion to prevent excessive hydraulic pressure supply to the supercharger. However, it is an object of the present invention to provide a lubricating device for an engine with a supercharger, which can increase the amount of oil supplied to the wall of the combustion chamber and improve the cooling performance.

[0013]

According to a first aspect of the present invention, in an engine having a supercharger for compressing and compressing intake air, a lubricating oil is supplied to at least a sliding portion of the engine. 1 lubrication path, and a supply oil pressure varying means that is provided upstream of the first lubrication path and that can set the oil pressure of the first lubrication path to a lower pressure than the supply oil pressure to the supercharger in a low rotation region of the engine. And a second lubrication path that is provided independently of the first lubrication path and that supplies lubricating oil to the sliding portion of the supercharger via an oil cooler, Is characterized in that

According to a second aspect of the present invention, in addition to the configuration of the first aspect of the present invention, the supply hydraulic pressure varying means is configured so that the hydraulic pressure of the first lubricating path is in a low rotation and low load region of the engine. Is a lubricator for an engine with a supercharger, which can be set to a pressure lower than the hydraulic pressure supplied to the supercharger.

According to a third aspect of the present invention, in addition to the configuration of the first or second aspect of the invention, the supply hydraulic pressure varying means is any one of a combustion chamber wall temperature and a parameter related to the temperature. According to the above, the lubrication device for an engine with a supercharger is characterized in that the hydraulic pressure in the first lubrication path is set to be higher than the hydraulic pressure supplied to the supercharger.

According to a fourth aspect of the present invention, in addition to the configuration of the first, second or third aspect of the present invention, the combustion chamber is provided between the oil cooler and the supercharger in the second lubricating path. A lubrication device for an engine with a supercharger, comprising supply control means for supplying a part of a second lubricating path with cooling oil for cooling to a combustion chamber wall in accordance with either a wall temperature or a parameter related to the wall temperature. It is characterized by

According to a fifth aspect of the present invention, in addition to the configuration of the fourth aspect of the invention, a supercharger is provided between the supply control means and the supercharger in the second lubricating path. The lubricating device for an engine with a supercharger is provided with a throttle that can ensure the required hydraulic pressure.

[0018]

According to the first aspect of the present invention, the second lubrication route is provided independently of the first lubrication route, and the supply hydraulic pressure varying means is provided upstream of the first lubrication route. Since it is provided, the lubricating oil supplied to the supercharger via the oil cooler of the second lubrication path in the low engine speed region ensures the supercharger required hydraulic pressure, while preventing the sliding parts of the engine from moving. The hydraulic pressure in the first lubrication path can be set lower than the hydraulic pressure supplied to the supercharger by the supply hydraulic pressure varying means.

As a result, the amount of end flow from the sliding portion can be reduced, and the temperature of the sliding portion can be increased to reduce the viscosity of oil.
By reducing the sliding resistance and reducing the hydraulic pressure, the driving resistance of the oil pump can be reduced, and the engine load can be reduced.

According to the second aspect of the present invention,
In addition to the effect of the invention described in claim 1, the supply hydraulic pressure varying means sets the hydraulic pressure in the first lubrication path to a lower pressure than the hydraulic pressure supplied to the supercharger in the low engine speed low load region (fuel consumption improving region) of the engine. Since the setting is made, the same effect as the above-mentioned claim 1 can be obtained in the above-mentioned fuel efficiency improvement region.

According to the invention of claim 3 of the present invention,
In addition to the effect of the invention described in claim 1 or 2, the supply hydraulic pressure varying means supplies the hydraulic pressure in the first lubrication path to the supercharger according to either the combustion chamber wall temperature or a parameter related to the temperature. Since the hydraulic pressure is set to be higher than the supply hydraulic pressure, the sliding portion of the engine can be sufficiently lubricated.

According to the invention of claim 4 of the present invention,
In addition to the effects of the invention according to claim 1, 2 or 3,
Between the oil cooler and the supercharger in the second lubrication path,
Since the supply control means for supplying a part of the lubricating oil for cooling of the second lubrication path to the combustion chamber wall in accordance with the combustion chamber wall temperature and any parameter related to the temperature is provided, the temperature of the combustion chamber wall Is above a predetermined value, the above-mentioned supply control means supplies the lubricating oil for cooling to the combustion chamber wall. As a result, there is an effect that the combustion chamber wall can be efficiently lubricated and cooled particularly in the output region of the engine, and knocking can be prevented from occurring.

According to the invention of claim 5 of the present invention,
In addition to the effect of the invention described in claim 4, since the throttle is provided, the throttle prevents excessive hydraulic pressure supply to the supercharger, thereby increasing the amount of oil supplied to the combustion chamber wall. Thus, there is an effect that the cooling property can be improved.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. The drawing shows a lubricating device for a rotary piston engine with a supercharger, and in FIG. 1, a tank (oil pan) 1
An oil strainer 2 is disposed in the oil strainer 2, and an oil pump 4 is connected to the oil strainer 2 via a suction pipe 3.

The discharge line 5 of the oil pump 4 described above is connected to one inlet port of the first valve V1 constituted by an electromagnetic three-way switching valve, and this discharge line 5 is connected.
An oil cooler 7 is connected to one branch line 6 branched from the above, and a first relief valve 9 is connected to the other branch line 8. The set pressure of the first relief valve 9 is set to, for example, about 11 kg / cm ^2, and the branch line 10 downstream of the oil cooler 7 is connected to the other inlet port of the first valve V1.

The outlet line 11 connected to the outlet port of the above-mentioned first valve V1 is connected to the inlet port of the second valve V2 constituted by the electromagnetic three-way switching valve, and the two outlet ports of this second valve V2 are connected to the two outlet ports. The first lubrication path 12 is connected. That is, the first lubrication path 12 includes a low pressure line 13 connected to one outlet port of the second valve V2, a high pressure line 14 connected to the other outlet port of the second valve V2, and both of these lines 13, 14 2 is provided, and a merging line 16 downstream of the merging point 15 is provided, and a front sliding portion 20 such as a front main bearing 18 and a rotor bearing 19 of the rotary piston engine 17 shown in FIG. It is configured to supply the lubricating oil to the rear side sliding portion 23 such as the side main bearing 21 and the rotor bearing 22.

A check valve 24 is provided in the low-pressure line 13 upstream of the above-mentioned joining point 15 in order to prevent the lubricating oil in the high-pressure line 14 from flowing back into the low-pressure line 13, while the check valve 24 is provided. An oil filter 25 is provided on the merging line 16 downstream of the point 15. Here, the oil passage 26 for supplying the lubricating oil to each of the bearings 18, 19, 21, 22 described above has an eccentric shaft 2 as shown in FIG.
It is formed within 7.

By the way, the supply oil pressure varying means 28 is provided upstream of the above-mentioned first lubricating path 12. As shown in FIG. 1, the supply hydraulic pressure varying means 28 includes the above-mentioned second valve V2.
And the second relief valve 29 connected upstream of the check valve 24 in the low pressure line 13, and the outlet line 11 described above.
And a third relief valve 30 connected to the second relief valve 30, the set pressure of the second relief valve 29 is about 1 kg / cm ² which is lower than the turbocharger required hydraulic pressure, and the set pressure of the third relief valve 30 is higher than the turbocharger required hydraulic pressure. The second valve V2 is set to 8 kg / cm ² in the fuel economy improvement region of the rotary piston engine 17 (low rotation and low load region, for example, an engine speed of 2500 rpm or less and an average effective pressure of 3 kg / cm ² or less). By selecting the low pressure line 13 which is set to 1 kg / cm ² by changing over, the hydraulic pressure of the first lubrication path 12 is set lower than the required hydraulic pressure of the turbocharger 31 (about 2 kg / cm ² ) and the rotary piston is set. Engine 17
In the output region (high rotation and high load region) of the above, by selecting the high pressure line 14 set to 8 kg / cm ² by switching the above-mentioned second valve V2, the oil pressure of the first lubrication path 12 is requested by the turbocharger 31. It is configured to set higher pressure than hydraulic pressure (about 2 kg / cm ² ).

On the other hand, at the branch point 32 on the downstream side of the oil cooler 7 described above, the second lubricating path 33 as a cooling line for constantly supplying low temperature lubricating oil to the sliding portion of the turbocharger 31 via the oil cooler 7. Is provided. The second lubrication path 33 is a path provided independently of the first lubrication path 12, and the hydraulic pressure supplied to the turbocharger 31 is supplied to the second lubrication path 33 by the turbocharger required oil pressure (about 2 kg / cm 2). A fixed throttle 34 as throttle means set in ² ) and an oil filter 35 are interposed.

Moreover, between the downstream of the oil cooler 7 and the upstream of the fixed throttle 34 in the above-mentioned second lubrication path 33, the temperature of the combustion chamber wall and the parameter related to the temperature (specifically the oil drop oil temperature) are set. Combustion chamber wall 36 according to either
A third valve V3 as a supply control means for supplying the lubricating oil for cooling is provided between the third valve V3 and the third valve V3. The third valve V3 is composed of an electromagnetic three-way switching valve. The sliding portion of the turbocharger 31 is connected via the throttle 34 and the oil filter 35, while the oil passage 37 is connected to the other outlet port of the third valve V3 described above, and the lubricating oil from the oil passage 37 is used for combustion. It is configured to cool the chamber wall 36.

The above-mentioned oil passage 37 is constructed as follows.
That is, the intermediate housing 40 is disposed between the front rotor housing 38 and the rear rotor housing 39, and the housing central portion as the insertion portion 41 of the eccentric shaft 27 is provided from the outer surface of the intermediate housing 40. The oil passage forming wall 42 is formed integrally with the oil passage forming wall 42, the oil passage 37 is formed inside the oil passage forming wall 42, and the front side combustion chamber wall 36 and the rear side combustion chamber wall 36 are formed below the oil passage 37. Two branched oil passages 43 and 44 directed to the combustion chamber wall 36 are formed. Further, an oil drop oil temperature sensor 46 is provided in the oil drop passage 45 formed in the above-mentioned intermediate housing 40.
Is installed.

FIG. 5 shows a control circuit of the lubricating device, which is a CPU
Reference numeral 50 denotes the engine speed Ne from the distributor 47, the intake negative pressure B from the boost sensor 48, the oil pan oil temperature To from the oil pan oil temperature sensor 49, and the oil drop oil temperature from the oil drop oil temperature sensor 46. Based on each signal input of Tr, the first valve V1, the second valve V2, and the third valve V1, according to the program stored in the ROM 51.
The valve V3 is driven and controlled, and the RAM 52 stores necessary data such as an oil pan set oil temperature to, an oil drop set oil temperature tr, and an engine load set value (see FIG. 6).

The switching mode of the valves V1, V2, V3 under the control of the CPU 50 is as shown in FIG. That is, when the current oil temperature To in the oil pan is lower than the set oil temperature to in the oil pan To <to, in order to supply the oil pump discharge oil to the first lubrication path 12, the first valve V1 is connected to the discharge line 5. When the current oil temperature To in the oil pan is higher than the set oil temperature to in the oil pan, the oil cooler 7 is connected to the outlet line 11.
The branch line 10 and the outlet line 11 are communicated with each other by the first valve V1 in order to supply the lubricating oil cooled in step 1 to the first lubricating path 12.

Further, both the current engine speed Ne and the intake negative pressure B and the current oil drop oil temperature Tr are within the set values, and the engine fuel consumption is improved (low load and low speed range).
Then, the outlet line 11 and the low pressure line 13 are communicated with each other by the second valve V2, and the set pressure of the first lubrication path 12 is set to be equal to the set pressure of the second relief valve 29 (about 1 kg / cm ² ). Output range of the engine (high-load high-speed range) in which any one of the current engine speed Ne and the intake negative pressure B and the current oil drop oil temperature Tr becomes equal to or higher than a set value
Alternatively, when the temperature of the combustion chamber wall is high, the outlet line 11 and the high pressure line 14 are communicated with each other by the second valve V2, and the set pressure of the first lubrication path 12 is set to the set pressure of the third relief valve 30 (about 8 kg / cm ² ). Set equal.

Furthermore, when the current oil drop oil temperature Tr is lower than the oil drop set oil temperature tr (for example, around 130 ° C. shown in FIG. 7) and Tr <tr, it is not necessary to lubricate and cool the combustion chamber wall 36. All the lubricating oil in the second lubricating path 33 is guided to the turbocharger 31 side by the third valve V3, and when the current oil drop oil temperature Tr is higher than the oil drop set oil temperature tr, the occurrence of knocking occurs when Tr> tr. Since it is necessary to lubricate and cool the combustion chamber wall 36 for the purpose of prevention, the lubricating oil in the second lubricating path 33 is diverted to the turbocharger 31 side and the combustion chamber wall 36 side by the third valve V3.

The operation of the illustrated embodiment having the above-mentioned structure will be described below. Lubricating oil at a low temperature corresponding to the required hydraulic pressure (about 2 kg / cm ² ) is always supplied to the sliding portion of the turbocharger 31, regardless of the rotational speed of the rotary piston engine 17. That is, the lubricating oil discharged from the oil pump 4 is discharged from the discharge line 5, the branch line 6,
The oil cooler 7, the branch point 32, the second lubrication path 33, the fixed throttle 34, and the oil filter 35 are supplied in this order to the sliding portion of the turbocharger 31. Here, the set pressure of the above-mentioned discharge line 5 is about 11 kg by the first relief valve 9.
Although it is set to / cm ² , the hydraulic pressure supplied to the turbocharger 31 is set to the required hydraulic pressure (about 2 kg / cm ² ) by the fixed throttle 34 provided upstream of the turbocharger 31.

On the other hand, when the rotary piston engine 17 rotates at a low speed, for example, at 2500 rpm or less shown in FIG.
Since the second valve V2 is switched to select the low pressure line 13, the line pressure of the first lubrication path 12 becomes the value set by the second relief valve 29, that is, about 1 kg / cm ² , and the front side sliding portion 20. Further, to the rear side sliding portion 23, a lubricating oil of about 1 kg / cm ² which is lower than the hydraulic pressure supplied to the turbocharger 31 is supplied through the above-mentioned joining line 16.

As a result, it is possible to reduce the amount of end flow from each of the sliding portions 20 and 23 described above, and the sliding portion 2
By increasing the temperature of 0 and 23, the viscosity of the oil can be reduced, the sliding resistance can be reduced, and the hydraulic pressure is about 1 kg / cm ²
Since the drive resistance of the oil pump 4 can be reduced by lowering it to 1, it is possible to reduce the engine load.

By the way, the rotary piston engine 17
At the time of high rotation of, for example, 2500 rpm or more shown in FIG. 8, the second valve V2 is switched to select the high pressure line 14, so the line pressure of the first lubrication path 12 is set by the third relief valve 30. The value is about 8 kg / cm ² ,
For the front side sliding portion 20 and the rear side sliding portion 23, the turbocharger 31 is connected via the above-mentioned joining line 16.
Since about 8 kg / cm ² of lubricating oil, which is higher in pressure than the oil pressure supplied to the sliding parts 20 and 23, is sufficiently lubricated.

The state of such a change in hydraulic pressure is shown in FIG.
In FIG. 8, a is the required hydraulic pressure of the turbocharger 31, b
Is the hydraulic pressure supplied to the turbocharger 31 according to the present embodiment,
C is the hydraulic pressure supplied to the turbocharger by the conventional lubrication device, d is the hydraulic pressure of the first lubrication path 12 according to the present embodiment, and e is the main gallery hydraulic pressure in the conventional lubrication device.

On the other hand, when the current oil drop oil temperature Tr from the oil drop oil temperature sensor 46 shown in FIGS. 3 and 5 exceeds the oil drop set oil temperature (for example, around 130 ° C.) shown in FIG. 7, the third valve Since V3 is switched so as to separately supply the lubricating oil in the second lubrication path 33 to both the turbocharger 31 side and the combustion chamber wall 36 side, the front side via the oil passage 37 and the branch oil passages 43, 44 described above. The low-temperature lubricating oil is supplied to the combustion chamber walls 36, 36 on the side and the rear side via the oil cooler 7. Therefore, the combustion chamber wall 36 can be efficiently lubricated and cooled particularly in the output region of the rotary piston engine 17, and knocking can be prevented.

That is, a control jet CJ for cooling the combustion chamber wall 36 is provided in the first lubrication path 12 (in the eccentric shaft 27 in FIG. 2),
Although the combustion chamber wall 36 is mainly cooled by the control jet CJ, in the transient from the fuel economy improvement region to the output region, that is, when the hydraulic pressure of the first lubrication path 12 is switched from 1 kg / cm ² to 8 kg / cm ² , Since the control jet CJ alone is insufficient for cooling, cooling is also performed from the combustion chamber wall cooling oil passage 37 of the second lubrication passage 33. From the branch oil passages 43 and 44 branched from the cooling oil passage 37, the above-mentioned combustion chamber wall 36
Is supplied with lubricating oil.

FIG. 9 shows another embodiment of the lubricating device for a rotary piston engine with a supercharger.
An electromagnetic switching type three-way switching valve is used as the second and third valves V1, V2 and V3, but in this embodiment shown in FIG. 9, the first, second and third valves CV1, CV2 and CV are used.
An electromagnetic switching type two-position three-port type directional control valve is used as reference numeral 3. Even with such a configuration, the same operation and effect as those of the previous embodiment can be obtained. Therefore, in FIG. 9, the same parts as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

In the correspondence between the configuration of the present invention and the above-described embodiment, the engine of the present invention corresponds to the rotary piston engine 17 of the embodiment. Similarly, the sliding portion of the engine is slid on the front side. Corresponding to the portion 20 and the rear sliding portion 23, the supercharger corresponds to the turbocharger 31,
The throttle corresponds to the fixed throttle 34, the combustion chamber wall temperature and parameters related to the temperature correspond to the oil drop oil temperature Tr, and the supply control means corresponds to the third valves V3, CV3 and the oil passage 37. However, the present invention is not limited to the configuration of the above-described embodiment, but may be applied to a lubricating device for a reciprocating engine with a supercharger such as an in-line multi-cylinder engine or a V-type engine. is there.

[Brief description of drawings]

FIG. 1 is a hydraulic circuit diagram showing a lubricating device for a rotary piston engine with a supercharger according to the present invention.

FIG. 2 is a sectional view of a rotary piston engine.

FIG. 3 is a cross-sectional view of an intermediate housing.

4 is a sectional view taken along the line AA of FIG.

FIG. 5 is a block diagram showing a control circuit of the lubricating device.

FIG. 6 is an explanatory diagram showing a switching state of each valve under CPU control.

FIG. 7 is a characteristic diagram showing a relationship between an oil drop oil temperature and a rotor temperature.

FIG. 8 is a characteristic diagram showing changes in hydraulic pressure with respect to engine speed.

FIG. 9 is a hydraulic circuit diagram showing another embodiment of the lubricating device for a rotary piston engine with a supercharger of the present invention.

[Explanation of symbols]

 7 ... Oil cooler 12 ... 1st lubrication path 17 ... Rotary piston engine 20 ... Front side sliding part 23 ... Rear side sliding part 28 ... Supply hydraulic pressure varying means 31 ... Turbocharger 33 ... Second lubrication path 34 ... Fixed throttle 36 ... Combustion chamber wall 37 ... Oil passage V3, CV3 ... Third valve

Claims (5)

[Claims] 1. An engine provided with a supercharger for compressing and pressurizing intake air, wherein a first lubricating path for supplying lubricating oil to at least a sliding portion of the engine and an upstream of the first lubricating path are provided. A supply hydraulic pressure varying means capable of setting the hydraulic pressure of the first lubrication route to a pressure lower than the supply hydraulic pressure to the supercharger in the low engine speed region, and the independent provision for the first lubrication route, A lubricating device for an engine with a supercharger, comprising a second lubrication path for supplying lubricating oil to the sliding portion of the supercharger via an oil cooler. 2. The supercharger according to claim 1, wherein the supply hydraulic pressure varying means is capable of setting the hydraulic pressure of the first lubrication path to be lower than the hydraulic pressure supplied to the supercharger in a low rotation and low load region of the engine. Lubricating device for engine. 3. The supply hydraulic pressure varying means is configured to be a first one in accordance with one of a combustion chamber wall temperature and a parameter related to the temperature.
The lubrication device for an engine with a supercharger according to claim 1 or 2, wherein the hydraulic pressure in the lubrication path is set to be higher than the hydraulic pressure supplied to the supercharger. 4. A part of the second lubrication path on the combustion chamber wall between the oil cooler and the supercharger in the second lubrication path, depending on the temperature of the combustion chamber wall and a parameter related to the temperature. The lubrication device for an engine with a supercharger according to claim 1, 2 or 3, further comprising a supply control means for supplying the cooling lubricating oil. 5. The engine with a supercharger according to claim 4, wherein a throttle capable of ensuring a required hydraulic pressure of the supercharger is provided between the supply control means and the supercharger in the second lubrication path. Lubricator.