JP2007321700A - Engine lubricating device and engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an engine lubricating device enabling miniaturization of an oil pump and an engine equipped with such an engine lubricating device. <P>SOLUTION: The engine 1 equipped with the engine lubricating device has a cylinder head 3 assembled on an upper side of a cylinder block 2, and an upper side oil pan 7 is arranged in the cylinder head 3. A supply hole 7a having a reed valve 7b installed therein is bored on the upper side oil pan 7. The reed valve 7b is opened by gas pressure of blow-by gas rising into the cylinder head 3 during engine operation, and lubricating oil is supplied to lubrication sections such as a crankshaft 4 and a camshaft 6 positioned in a lower side of the upper side oil pan 7. Dripping lubricating oil is stored in a lower side oil pan 5, is pumped up by an oil pump 12 and is collected to the upper side oil pan 7 again. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an engine lubrication device mounted on an engine that uses fuel such as light oil as lubricating oil.

  Conventionally, a light oil lubricated diesel engine in which a reservoir for separating bubbles is disposed between a fuel tank and a diesel engine, and a lubricating fuel circulation circuit and a combustion fuel circulation circuit are configured between the reservoir and the engine. Is disclosed (Patent Document 1). In such a light oil lubricated diesel engine, light oil as a fuel is also used as a lubricant for each part of the engine and circulates through each part of the engine. For this reason, the oil only for lubrication is unnecessary, and the effort of oil replacement can be saved.

  FIG. 3 is an explanatory diagram showing a schematic configuration mainly of a fuel supply portion of the fuel lubricated diesel engine 100 described in Patent Document 1. As shown in FIG. The fuel lubricated diesel engine 100 includes a fuel tank 101, a reservoir tank 102, and an oil pan 103. The fuel tank 101 and the reservoir tank 102 communicate with each other through an oil passage 106 including a cementer (oil separator) 104 and a supply pump (oil feed pump) 105.

  The fuel-lubricated diesel engine 100 includes a lubrication-system fuel circulation circuit 108 that supplies fuel as lubricant to each part 107 of the engine that requires supply of lubricant. The lubrication system fuel supply circuit 108 is provided with a cooler 112, a filter 109, and a lubrication pump 110. By driving the lubrication pump 110, fuel is sucked up from the reservoir tank 102 and supplied to each part 107 of the engine. ing. The fuel after being supplied to each part 107 of the engine flows down into the oil pan 103, is sucked up by the scavenge pump 111, and is returned to the reservoir tank 102 again.

  The fuel-lubricated diesel engine 100 also has a combustion system fuel circulation circuit 113 that supplies fuel to an injection system 114 that injects fuel into the cylinder. The combustion system fuel circulation circuit 113 is provided with a cooler 112, a filter 115, and an injection pump 116 that are common to the lubrication system fuel circulation circuit 108. By driving the injection pump 116, fuel is stored in the reservoir tank 102. The water is sucked up and supplied to the injection system 114. Of the fuel supplied to the injection system 114, the fuel that has not been used for combustion is returned to the reservoir tank 102 again.

Japanese Utility Model Publication No. 60-194112

  As described above, in the fuel-lubricated diesel engine 100 described in Patent Document 1, the lubricating oil is supplied to each part 107 of the engine using the lubrication pump 110. Here, the oil passage stretched in the engine and leading to each part 107 of the engine is narrow, long, or opened in the middle, so that it is pumped at a pressure considering the pressure loss between them. Yes. For this reason, the lubrication pump 110 needs to have a certain size. Such a structure of the lubrication system adopts substantially the same configuration in a general engine in which lubricating oil is separately prepared in addition to fuel.

  Therefore, an object of the present invention is to provide an engine lubrication device capable of reducing the size of an oil pump and an engine equipped with such an engine lubrication device.

In order to achieve the above object, an engine lubrication device of the present invention is an engine lubrication device that uses fuel as lubricating oil, and is disposed above a lubrication site in a cylinder head, and supplies the lubricating oil dropwise. An upper oil pan having a hole, lubricating oil supply means for supplying lubricating oil to the upper oil pan, and lubricating oil recovery means for recovering dripped lubricating oil to the oil pan. (Claim 1). The engine lubricating device of the present invention is mounted on an engine of a type that uses fuel as lubricating oil. Here, light oil is assumed as a fuel used for such an engine. Light oil is less viscous than general engine oil. For this reason, it can be dripped smoothly from the supply hole provided in the upper oil pan. The dropped lubricating oil is supplied to a lubrication site such as around the camshaft in the cylinder head.
The lubrication site includes each part in the engine that requires supply of lubricating oil.

  The upper oil pan in such an engine lubricating device can be arranged in a cylinder head cover (claim 2).

  Further, the lubricating oil supply means in such an engine lubricating device may be configured as a supply pump that supplies fuel from a fuel tank to an engine injection system (claim 3). For example, an upper oil pan is disposed between the fuel tank and the supply pump, and the fuel in the fuel tank, that is, lubricating oil is sucked up and supplied into the upper oil pan by driving the supply pump. it can. In the case of such a configuration, the fuel in the upper oil pan is supplied to the injection system disposed downstream of the supply pump.

  The supply hole in such an engine lubrication apparatus may be configured to include a differential pressure valve that opens by the gas pressure of blow-by gas. For example, if the supply hole is not closed when the engine is stopped, the lubricating oil in the upper oil pan flows down, and the supply of the lubricating oil to the lubrication site is delayed when the engine is restarted. In view of this, it is possible to employ a configuration including a differential pressure valve that can prevent the lubricating oil from flowing down from the supply hole when the engine is stopped. As such a differential pressure valve, for example, a reed valve that can be pushed open by blow-by gas generated during engine operation can be employed.

  The lubricating oil recovery means in such an engine lubricating device may include a lower oil pan attached to the lower part of the engine and an oil pump that sucks lubricating oil from the lower oil pan to the upper oil pan. (Claim 5). Here, the oil pump can be very small as compared with a conventional lubrication pump. This is because the conventional lubricating pump has to pump the lubricating oil at a certain pressure in order to supply the lubricating oil to the oil passage stretched in the engine. This is because it is only necessary to pump the lubricating oil from the oil pan to the upper oil pan. In addition, although there is an oil pan attached to the lower part of the conventional engine, the lower oil pan in the present invention only has to function as a tray for the lubricating oil dripping from the upper side. Therefore, it may be shallower than a conventional general oil pan.

  Thus, when setting it as the structure provided with the oil pump, the said oil pump can be set as the structure connected to the piston oil jet (Claim 6). Some conventional engines are provided with a piston oil jet that injects lubricating oil on the back side of the piston or the like. This is because the oil pump supplies the lubricating oil to the piston oil jet.

  When the oil pump is provided as described above, the oil pump is connected to a piston oil jet, and the oil pump is rotated in the reverse direction so that the lubricating oil in the upper oil pan is supplied to the piston. It can be set as the structure supplied to an oil jet (Claim 7). As described above, the oil pump serves to pump the lubricating oil from the lower oil pan to the upper oil pan. When the rotation direction during such a function is a forward rotation, the oil pump can be rotated in the reverse direction to supply the lubricating oil in the upper oil pan to the piston oil jet. For example, it is assumed that the amount of lubricating oil in the lower oil pan is small when the engine is started. In such a state, appropriate lubricating oil can be supplied from the piston oil jet to the periphery of the piston. There is a risk of not. In addition, it takes time for the lubricating oil dripping from the upper oil pan to reach the periphery of the piston. Accordingly, even when the amount of lubricating oil in the lower oil pan is insufficient, it is possible to ensure appropriate lubricating performance around the piston by supplying the lubricating oil from the upper oil pan.

  As described above, the engine lubricating device of the present invention lubricates each part mainly by dripping the lubricating oil in the upper oil pan downward. The periphery of the crankshaft is also intended to ensure lubrication performance by the dripping of the lubricating oil dripping from above or the lubricating oil that is scraped up by itself. For this reason, it is desirable that the engine equipped with the engine lubrication device of the present invention has a configuration in which the bearing at the lubrication site is a rolling bearing in order to obtain more appropriate lubrication characteristics.

  According to the present invention, since the lubricating oil is dropped and supplied from the upper oil pan disposed above the lubrication site in the cylinder head to the lubrication site, the lubrication site is not provided with a high-pressure lubrication pump. Lubrication performance can be ensured.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic diagram showing a schematic configuration of an engine 1 equipped with an engine lubricating device of the present invention. The engine 1 is a four-cylinder engine that employs a type that uses light oil as a fuel as a lubricating oil.
FIG. 1 mainly shows the arrangement of each component and the connection relationship between each component, and the scale of each component is different from the actual one.

  In the engine 1, a cylinder head 3 is assembled on the upper side of the cylinder block 2. A crankshaft 4 is disposed in the cylinder block 2. A lower oil pan 5 is provided at the lower part of the cylinder block 2. A camshaft 6 is disposed in the cylinder head 3, and an upper oil pan 7 is disposed above the camshaft 6. Here, each of the crankshaft 4 and the camshaft 6 corresponds to a lubrication site in the present invention. In addition to these locations, the lubrication sites include locations that require supply of lubricating oil. Thus, the upper oil pan 7 is disposed above the lubrication site in the engine 1. Roller bearings such as ball bearings are employed as bearings in these lubrication sites.

  The upper oil pan 7 is provided with an oil supply hole 7a for dripping the lubricating oil. Reed valves 7b, which are differential pressure valves that are opened by the gas pressure of the blow-by gas, are mounted in the oil supply holes 7a. The reed valve 7 b is mounted on the inner side of the upper oil pan 7 so as not to be opened due to the weight of the lubricating oil stored in the upper oil pan 7.

  A fuel tank 8 is connected to the upper oil pan 7. The upper oil pan 7 is connected to the injection system 10 via a supply pump 9. The supply pump 9 sucks up the fuel in the fuel tank 8 and supplies it to the injector at a high pressure. By arranging the upper oil pan 7 between the supply pump 9 and the fuel tank 8, the fuel tank The fuel in 8 can be supplied into the upper oil pan 7 as lubricating oil. The injection system 10 includes a common rail, an injector, etc., not shown. Such a supply pump 9 corresponds to the lubricating oil supply means in the present invention.

  A strainer 11 is disposed in the lower oil pan 5, and the strainer 11 is connected to an oil pump 12. One end of a pumping pipe 13 that pumps the lubricating oil in the lower oil pan 5 to the upper oil pan 7 is connected to the oil pump 12. The other end of the pumping pipe 13 is connected to the upper oil pan 7. The oil pump 12 is an electric pump and is connected to an ECU (Electronic control unit) 14. The oil pump 12 can rotate forward and backward in accordance with a command from the ECU 14. Further, the strainer 11 is mounted with an on-off valve 15 having an electromagnetic actuator between the strainer 11 and the oil pump 12. This on-off valve 15 is also connected to the ECU 14. The oil pump 12 is connected to a piston oil jet 17 that injects lubricating oil toward the piston 16 incorporated in the cylinder block 2. The lower oil pan 5, the oil pump 12, and the piston oil jet 17 are included in the lubricating oil recovery means in the present invention.

  Next, the operation of the engine lubrication apparatus configured as described above will be described. FIG. 2 is an enlarged view of the periphery of the upper oil pan 7, (a) shows a state where the engine 1 is stopped, and (b) shows a state where the engine 1 is operating. When the engine 1 is stopped, the reed valve 7b closes the supply hole 7a. For this reason, the lubricating oil in the upper oil pan 7 is held in the upper oil pan 7. That is, dripping of the lubricating oil in the upper oil pan 7 through the supply hole 7a is limited. As a result, the amount of lubricating oil in the lower oil pan 5 does not increase. Here, the lower oil pan 5 is a tray for dripping lubricating oil, and does not have a capacity for storing a large amount of lubricating oil. For this reason, it is assumed that the lubricating oil injected from the piston oil jet 17 immediately after the engine is started is not stored in the lower oil pan 5. In order to cope with such a situation, the ECU 14 that has received the start signal of the engine 1 issues a command to the oil pump 12 to perform reverse rotation. In addition, the ECU 14 issues a command to close the on-off valve 15 at the same time. Thereby, lubrication can be supplied to the piston oil jet 17 from the upper oil pan 7 in which a large amount of lubricating oil is stored, and good lubrication characteristics around the piston 16 can be ensured immediately after the engine 1 is started. . When such control is performed, good lubricating characteristics around the piston 16 can be ensured without waiting until the lubricating oil dripping from the supply hole 7a reaches the periphery of the piston 16. Note that the bearing of the crankshaft 4 is lubricated by the splash of the lubricating oil in the lower oil pan 5 when the crankshaft 4 rotates, so the on-off valve 15 is opened and the lower oil pan is opened. It is also possible to perform control to increase the amount of lubricating oil in 5 to easily cause splashing.

  When the engine 1 is started, blow-by gas is generated, and the generated blow-by gas also rises into the cylinder head 3 as indicated by an arrow 18. Then, the reed valve 7b opens the supply hole 7a as shown in FIG. When the supply hole 7a is opened, the lubricating oil in the upper oil pan 7 starts dripping. The dropped lubricating oil is supplied to the lubricating parts such as the camshaft 6 and the crankshaft 4 and is used for lubricating each part. Here, since the lubricating oil is light oil, the viscosity is low even when cold, and the oil is smoothly dropped from the supply hole 7a and supplied to the lubrication site. Further, the lubricating oil is merely dropped and is not supplied with pressure, but since the bearing at the lubrication site is a rolling bearing, good lubricating characteristics can be ensured.

  The lubricating oil in the upper oil pan 7 is also used as fuel. Since the upper oil pan 7 is connected to the supply pump 9, it is also consumed as fuel. Therefore, although the lubricating oil in the upper oil pan 7 is gradually consumed, the fuel (lubricating oil) in the fuel tank 8 is replenished into the upper oil pan 7 by the suction action of the supply pump 9.

  In addition, after starting the engine, the ECU 14 issues a command to the oil pump 12 to perform normal rotation and issues a valve opening command to the on-off valve 15. Thereby, the lubricating oil dripped from the upper oil pan 7 and stored in the lower oil pan 5 can be recovered again in the upper oil pan 7.

  As described above, the oil pump 12 in the present invention only needs to pump up the lubricating oil from the lower oil pan 5 to the upper oil pan 7. That is, it is not necessary to pump the lubricating oil so as to reach the oil passages stretched around each part of the engine as in the conventional lubricating pump. For this reason, the oil pump 12 is smaller than the conventional lubrication pump. By employing the small oil pump 12, the friction during operation can be reduced.

  The above-described embodiments are merely examples for carrying out the present invention, and the present invention is not limited thereto. Various modifications of these embodiments are within the scope of the present invention. It is apparent from the above description that various other embodiments are possible within the scope.

It is a mimetic diagram showing a schematic structure of an engine carrying an engine lubrication device. It is an enlarged view around the upper oil pan, (a) shows a state where the engine is stopped, (b) shows a state where the engine is operating. It is explanatory drawing which showed schematic structure of the fuel supply part mainly of the conventional fuel lubrication type diesel engine.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine 2 Cylinder block 3 Cylinder head 4 Crankshaft 5 Lower oil pan 6 Cam shaft 7 Upper oil pan 7a Supply hole 7b Reed valve 8 Fuel tank 9 Supply pump 10 Injection system 11 Strainer 12 Oil pump 13 Pumping pipe 14 ECU
15 On-off valve 16 Piston 17 Piston oil jet

Claims (8)

An engine lubrication device that uses fuel as lubricating oil,
An upper oil pan disposed above the lubrication part in the cylinder head and provided with a supply hole for dripping the lubricating oil;
Lubricating oil supply means for supplying lubricating oil to the upper oil pan;
Lubricating oil recovery means for recovering the dropped lubricating oil in the oil pan;
An engine lubrication device comprising: The engine lubricating device according to claim 1, wherein
The engine lubrication device, wherein the upper oil pan is disposed in a cylinder head cover. The engine lubrication device according to claim 1 or 2,
The engine lubricating device according to claim 1, wherein the lubricating oil supply means is a supply pump that supplies fuel from a fuel tank to an engine injection system. The engine lubrication device according to any one of claims 1 to 3,
The engine lubrication device according to claim 1, wherein the supply hole includes a differential pressure valve that is opened by a gas pressure of blow-by gas. The engine lubrication device according to any one of claims 1 to 4,
The lubricating oil recovery means includes a lower oil pan attached to the lower part of the engine,
An engine lubrication device comprising an oil pump for sucking lubricating oil from the lower oil pan to the upper oil pan. The engine lubrication device according to any one of claims 1 to 4,
The lubricating oil recovery means includes a lower oil pan attached to the lower part of the engine,
An oil pump for sucking up lubricating oil from the lower oil pan to the upper oil pan;
An engine lubrication device, wherein the oil pump is connected to a piston oil jet. The engine lubrication device according to any one of claims 1 to 4,
The lubricating oil recovery means includes a lower oil pan attached to the lower part of the engine,
An oil pump for sucking up lubricating oil from the lower oil pan to the upper oil pan;
The oil pump is connected to a piston oil jet and reversely rotates the oil pump to supply the lubricating oil in the upper oil pan to the piston oil jet. The engine lubrication device according to any one of claims 1 to 7 is mounted,
An engine characterized in that the bearing at the lubrication part is a rolling bearing.

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