JP6409809B2 - Engine oil supply device - Google Patents

Description

  The present invention relates to an engine oil supply apparatus.

  As a hydraulic drive variable valve mechanism for an engine, for example, a mechanism for converting a cam driving force into hydraulic pressure and driving an intake valve and an exhaust valve by hydraulic pressure as described in Patent Document 1 is known. . According to this mechanism, the valve timing and the valve lift amount can be changed by appropriately relieving the hydraulic pressure generated with the rotation of the cam.

  In such a hydraulically driven variable valve mechanism, when bubbles are mixed into oil for generating hydraulic pressure, the valve lift amount and valve timing are shifted, and the desired valve opening / closing characteristics cannot be obtained. Normally, oil is supplied to the valve mechanism from an oil pan attached to the lower part of the cylinder block. The main factor for mixing bubbles in the oil is that the oil collides with the counterweight rotating on the crankshaft in the middle of dropping from each part of the engine to the oil pan. When oil collides with the counterweight and is bounced up, air is caught in the oil and bubbles are mixed.

  Regarding the problem of air bubbles mixed in oil, Patent Document 2 describes that a buffer plate for temporarily receiving oil falling from each part of the engine is provided in the crankcase. The bubbles are separated from the oil by the buffer plate, and the oil from which the bubbles are separated is dropped little by little from the return hole provided in the buffer plate to the oil pan.

JP 2009-121481 A JP 2010-019098 A

  However, in order for air bubbles to escape from the oil, it is necessary for the oil to stay on the buffer plate for a certain period of time. Oil that falls near the return hole of the buffer plate has a short residence time on the buffer plate and Falls into the oil pan without leaving. That is, just because the buffer plate is provided, the bubbles do not completely escape from the oil falling on the oil pan.

  An object of the present invention is to take measures against the problem that oil mixed with bubbles is supplied to a hydraulically driven variable valve mechanism that drives an intake valve or an exhaust valve.

  In order to solve the above problems, the present invention is provided with an oil reservoir for supplying oil to the hydraulically driven variable valve mechanism separately from a reservoir that receives oil falling from each part of the engine. .

The engine oil supply device disclosed herein is
An intake valve configured to be able to open and close the intake port provided in the cylinder;
An exhaust valve configured to open and close an exhaust port provided in the cylinder;
A hydraulically driven variable valve mechanism configured to be operable to open and close at least one of the intake valve and the exhaust valve;
An oil supply device for an engine equipped with
A first oil pump for supplying oil to a first oil demanding part of the engine;
A second oil pump for supplying oil to a second oil requesting unit including the hydraulically driven variable valve mechanism other than the first oil requesting unit;
A first oil that is provided as an oil supply source for the first oil pump, is attached to a lower part of a cylinder block of the engine, and receives falling oil that falls through a crankcase in which a crankshaft is disposed. A reservoir,
A second oil storage section that is partitioned from the first oil storage section by a wall and provided so that the falling oil does not directly enter as an oil supply source for the second oil pump;
A return oil path for returning the oil supplied to the second oil request unit to the second oil storage unit so that the falling oil is not mixed;
The wall that divides the first oil reservoir and the second oil reservoir is provided at a position lower than the minimum oil level in the first oil reservoir , and the oil is supplied from the first oil reservoir to the second oil reservoir. In order to be supplied to the oil reservoir, the first oil reservoir and the communication portion that communicates with the second oil reservoir are provided.

  According to this oil supply device, the oil that has fallen through the crankcase and mixed with bubbles by stirring by the crankshaft enters the first oil reservoir, but the return oil path to the second oil reservoir Since the oil that has passed through is prevented from being agitated by the crankshaft, the oil containing such bubbles does not enter the second oil reservoir. In addition, the return oil path returns oil from the second oil requesting section to the second oil storing section separately from the falling oil, so that it is possible to prevent oil mixed with bubbles from entering the second oil storing section. Accordingly, it is possible to avoid the supply of oil mixed with bubbles to the hydraulically driven variable valve mechanism by driving the second oil pump, which is advantageous in opening and closing the intake valve and the exhaust valve with the desired opening / closing characteristics. It is possible to suppress a decrease in fuel consumption performance of the engine.

In addition, a communication portion that connects the first oil storage portion and the second oil storage portion to a portion that is lower than the minimum oil level height in the first oil storage portion in the wall that divides the first oil storage portion and the second oil storage portion. Therefore, even if a part of the oil comes out from the oil supply system on the second oil storage part side, the oil is supplied from the first oil storage part to the second oil storage part through the communication part. This compensates for the decrease in oil in the second oil reservoir. Further, the second oil reservoir communicates with a relatively low part of the first oil reservoir, and the oil in the part of the first oil reservoir has a small amount of air bubbles. (2) The problem of air bubbles in the oil reservoir can be avoided in the oil replenishment to the oil reservoir.

  In a preferred embodiment, the first oil reservoir and the second oil reservoir are provided in an oil pan attached to the lower part of the cylinder block of the engine. For example, the first oil storage part may be configured by an oil pan, and the second oil storage part may be provided in the oil pan.

  According to this, it becomes easy for the oil of the 1st oil storage part of an oil pan to suppress by the 2nd oil storage part that it is flowing and deviating at the time of the ramp running of a vehicle, or turning. Therefore, it is advantageous to avoid the oil suction port related to the first oil pump from being exposed from the oil in the first oil reservoir. In addition, since the oil drain hole of the second oil storage part can be brought close to the oil drain hole of the first oil storage part, it is advantageous for improving the maintainability.

  In a preferred embodiment, an oil pan formed by integrally forming the first oil storage part and the second oil storage part is attached to the lower part of the cylinder block of the engine. According to this, the wall which partitions the said oil storage part in an oil pan will be made, and it will become advantageous to the rigidity improvement of an oil pan. Therefore, it is advantageous for preventing the oil pan from resonating with respect to engine vibration, and thus for suppressing noise. In addition, as compared with the case where both oil reservoirs are assembled separately and assembled to the engine, the number of assembling steps is reduced, which is advantageous for cost reduction.

  In a preferred embodiment, the second oil reservoir is integrally formed with the engine cylinder block. According to this, the second oil reservoir becomes a reinforcing element for the cylinder block, which is advantageous for reducing vibration and noise of the engine body.

According to the present invention, a first oil pump that supplies oil to a first oil request portion of an engine, a second oil pump that supplies oil to a second oil request portion including a hydraulically driven variable valve mechanism, and an engine Separately from the first oil reservoir for the first oil pump that receives the fallen oil and the first oil reservoir, the second oil reservoir for the second oil pump provided so that the fall oil does not enter directly And a return oil passage for returning oil from the second oil requesting section to the second oil storing section, and a first oil storing section in a wall that divides the first oil storing section and the second oil storing section. the first oil reservoir and the second oil reservoir provided in the lower portion than the minimum oil level height because have a communication portion for communicating the oil containing air bubbles in the hydraulic-driven variable valve mechanism is supplied in Further, by supplying the oil from the first oil reservoir through the communicating portion to the second oil reservoir, the decrease in the oil in the second oil reservoir is compensated. This is advantageous in opening and closing the intake and exhaust valves with the desired opening and closing characteristics.

The front view of an engine. The figure which shows the structure of a hydraulic drive type variable valve mechanism. The figure which shows the structure of an oil supply apparatus. The top view of an oil pan. VV sectional view taken on the line of FIG. The perspective view of the oil pan cut | disconnected by the VI-VI line of FIG. Sectional drawing of the oil pan which concerns on another embodiment. The front view of the engine which concerns on another embodiment.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The following description of the preferred embodiments is merely exemplary in nature and is not intended to limit the invention, its application, or its use.

  An engine 1 according to the embodiment shown in FIG. 1 is a multi-cylinder engine mounted on a vehicle, and a cylinder block 3 provided with a plurality of cylinders 2 (only one cylinder is shown in FIG. Two cylinders are provided in series), and a cylinder head 4 and an oil pan 5 which is attached to the lower portion of the cylinder block 3 and stores oil. A piston 8 connected to the crankshaft 7 via a connecting rod 6 is fitted into each cylinder 2 so as to be able to reciprocate. A counterweight 9 is provided on the crankshaft 7. An engine combustion chamber 10 is defined by the cylinder 2, the cylinder head 4 and the piston 8.

  The cylinder head 4 is provided with an intake port 11 and an exhaust port 12 that open to the combustion chamber 10. The intake port 11 and the exhaust port 12 are provided with an intake valve 13 and an exhaust valve 14 that open and close the intake and exhaust ports on the combustion chamber 10 side. The intake valve 13 and the exhaust valve 14 are urged by a return spring (reference numeral 19 in FIG. 2) in a direction to close the opening. When the intake valve 13 and the exhaust valve 14 each enter the combustion chamber 10 against the urging force of the return spring, the opening is opened. An intake passage 16 and an exhaust passage 17 each having a throttle valve 15 are connected to each of the intake port 11 and the exhaust port 12. A downstream side of the intake passage 16 from the throttle valve 15 and the cylinder head space are connected by a blow-by gas passage 18.

  The cylinder head 4 is provided with a hydraulically driven variable valve opening / closing mechanism 40 as a hydraulically driven variable valve mechanism for opening / closing the intake valve 13 and the exhaust valve 14 of each cylinder 2.

<Regarding the hydraulically driven variable valve opening / closing mechanism 40>
As shown in FIG. 2, the hydraulically driven variable valve opening / closing mechanism 40 transmits the power of the cam 44 that is rotationally driven by the crankshaft 7 to the intake valve 13 or the exhaust valve 14 (hereinafter, “ The intake valve 13 or the like "is transmitted to the intake valve 13 or the like. For this purpose, the valve opening / closing mechanism 40 includes an oil supply passage 41, an oil storage chamber 42, a hydraulic control valve 43, a first transmission chamber 45, and a second transmission chamber 46. According to the valve opening / closing mechanism 40, continuous fine control of the opening / closing timing and the lift amount of the intake valve 13 and the like is possible by adjusting the hydraulic pressure.

  The oil supply passage 41 includes oil passages 41a, 41b, and 41c branched in three directions. A hydraulic control valve 43 is provided at the intersection of the oil passages 41a to 41c. The oil passage 41 a is connected to the oil storage chamber 42. The oil passage 41b is connected to a second transmission chamber 46 for transmitting hydraulic pressure to the intake valve 13 and the like. The oil passage 41c is connected to the first transmission chamber 45 for generating hydraulic pressure.

  The oil storage chamber 42 stores oil to be supplied to the main body (the first and second transmission chambers 45 and 46 and the oil passages 41b and 41c) of the valve opening / closing mechanism 40. The replenishment oil is supplied to the oil storage chamber 42 through a second oil supply passage 33 described later provided with a check valve 50.

  The first transmission chamber 45 is formed in a cylinder shape, and a piston 47 is inserted therein. A rod 47 a coupled to the piston 47 is in contact with the rocker arm 49. As the cam 44 rotates, the piston 47 is pushed through the rocker arm 49 and the rod 47a. As a result, hydraulic pressure for transmitting the driving force by the cam 44 to the intake valve 13 or the like is generated in the first transmission chamber 45.

  The second transmission chamber 46 is formed in a cylinder shape, and a piston 52 is inserted therein. A stem such as an intake valve 13 is coupled to the piston 52. The hydraulic pressure generated in the first transmission chamber 45 is transmitted to the second transmission chamber 46 through the oil passage 41c, the hydraulic control valve 43, and the oil passage 41b. The piston 52 is pushed by this hydraulic pressure, and the intake valve 13 and the like are lifted.

  The hydraulic control valve 43 is electrically connected to a control unit 100 described later. The hydraulic control valve 43 operates according to a control signal from the control unit 100 in a closed state where the oil path 41a and the oil path 41b are blocked and an open state where the oil path 41a and the oil path 41b are communicated. To do.

  When the hydraulic control valve 43 is closed, the power transmitted from the cam 44 to the first transmission chamber 45 is hydraulically transmitted to the second transmission chamber 46 through the oil passages 41b and 41c, and the intake valve 13 and the like are opened and closed. To do. When the hydraulic control valve 43 is opened, the oil in the second transmission chamber 46 is relieved to the oil storage chamber 42 through the oil passages 41a and 41b, so that the hydraulic pressure is not transmitted from the first transmission chamber 45 to the second transmission chamber 46. . Therefore, the intake valve 13 or the like is in a state where the opening of the intake port 11 or the like is closed by the return spring.

  Here, in the valve opening / closing mechanism 40, for example, between the cylinder constituting the first transmission chamber 45 and the rod 47a of the piston 47, between the cylinder constituting the second transmission chamber 46 and the rod of the piston 52, etc. There is a gap. Therefore, oil leaks from the gap not only during operation of the engine 1 but also when the engine 1 is stopped. Thus, when the operating oil between the first transmission chamber 45 and the second transmission chamber 46 of the valve opening / closing mechanism 40 decreases, the desired valve opening / closing characteristics cannot be obtained.

  In view of this, the oil storage chamber 42 is provided in the valve opening / closing mechanism 40, and oil is supplied from the oil storage chamber 42 to the main body of the valve opening / closing mechanism 40 by the gravity supply method as operating oil. The oil storage chamber 42 is a cylinder head that is positioned higher than the main body of the valve opening / closing mechanism 40 when the engine 1 is disposed in the vehicle in order to reliably supply oil to the main body of the valve opening / closing mechanism 40. 4 is provided. An air / oil drain hole 48 is provided in the upper part of the oil reservoir chamber 42 for draining excess oil generated by opening the air or the hydraulic control valve 43. An oil passage 51 is connected to the air / oil drain hole 48. The downstream end of the oil passage 51 opens into the cylinder head space above the cam 44 and the rocker arm 49 so that surplus oil can be supplied to the cam 44 and the rocker arm 49 as lubricating oil.

  Oil mist generated in the cylinder head space is introduced into the intake passage 16 by the blow-by gas passage 18 shown in FIG.

<About oil supply device>
Next, an oil supply device for the engine 1 provided with the hydraulically driven variable valve opening / closing mechanism 40 will be described.

  As shown in FIG. 3, the oil supply device includes a first oil pump 21 that supplies oil to the first oil request unit 20 </ b> A of the engine 1 and a second oil that supplies oil to the second oil request unit 20 </ b> B of the engine 1. And a pump 22. The first oil pump 21 is a positive displacement variable displacement mechanical oil pump that is driven by the crankshaft 7, and supplies oil to the first oil request unit 20 </ b> A through the first oil supply passage 26. The second oil pump 22 is an electric oil pump that is driven by electric power supplied from the battery of the vehicle, and supplies oil to the second oil request unit 20 </ b> B through the second oil supply passage 33. The first oil supply passage 26 and the second oil supply passage 33, that is, the first oil pump 21 and the second oil pump 22 are provided in parallel.

  The first oil requesting unit 20A is an engine lubrication requesting unit, a cooling requesting unit, and / or a hydraulic device, and is supplied with oil through a head gallery, an oil jet passage, a main gallery, and the like. For example, the oil sent to the head gallery is supplied to a cam journal or the like, and then received by the upper deck of the cylinder head 4 and returned to the second oil reservoir 23. The oil sent to the oil jet passage is ejected from the oil jet to the piston sliding portion and falls to the oil pan 5. The lubricating oil sent to the main gallery of the cylinder block 3 is supplied to the connecting rod bearing or the like from the journal of the crankshaft 7 and the oil hole in the shaft, and falls to the oil pan 5.

  The second oil request unit 20B is an oil request unit including the valve opening / closing mechanism 40 other than the first oil request unit 20A, and the oil supplied to the second oil request unit 20B is supplied to the first oil supply unit 20A. The oil is received at a place different from the oil, for example, a region provided by partitioning the inside of the upper deck of the cylinder head 4, and returned to the second oil reservoir 24 through the return oil passage 37. In the present embodiment, the oil discharged from the second oil pump 22 is specifically supplied to the oil storage chamber 42 of the valve opening / closing mechanism 40.

  The oil pan 5 includes a first oil reservoir 23 that is an oil supply source of the first oil pump 21 and an oil supply source dedicated to the second oil pump 22, in other words, an oil supply source dedicated to the valve opening / closing mechanism 40. A second oil reservoir 24 is provided. An oil strainer 25 of the first oil pump 21 is provided in the first oil reservoir 23. The first oil pump 21, the oil filter 27, and the oil cooler 28 are provided in this order from the upstream side to the downstream side in the first oil supply passage 26 extending from the oil strainer 25 to the first oil requesting portion 20A. . In addition, since the oil cooler 28 is provided as appropriate, it does not necessarily have to be provided.

  The first oil supply passage 26 is provided with a linear solenoid pressure control valve 29 that controls the discharge pressure of the first oil pump 21 and a first hydraulic sensor 30 that detects the oil pressure downstream of the oil cooler 28. ing. The pressure control valve 29 controls the discharge pressure of the first oil pump 21 so that the pressure of the oil supplied to the first oil requesting unit 20A becomes an optimum pressure according to the operating state of the engine 1. . The operation of the pressure control valve 29 is controlled by the control unit 100 based on the engine operating state and the detected pressure of the first hydraulic pressure sensor 30.

  An oil strainer 32 of the second oil pump 22 is provided in the second oil reservoir 24. The second oil pump 22, the oil filter 34, and the oil cooler 35 are provided in this order from the upstream side to the downstream side in the second oil supply passage 33 extending from the oil strainer 32 to the oil storage chamber 42 of the valve opening / closing mechanism 40. It has been. Note that the oil cooler 35 is also provided as appropriate as the oil cooler 28, and is not necessarily provided. Here, the second oil supply passage 33 branches on the downstream side thereof and is connected to the oil storage chamber 42 of the valve opening / closing mechanism 40 of each of the intake valve 13 and the exhaust valve 14 of each cylinder 2. The second oil supply passage 33 is provided with a second oil pressure sensor 36 that detects the oil pressure downstream of the oil cooler 35 and upstream of the valve opening / closing mechanism 40. The operation of the second oil pump 22 is controlled by the control unit 100 so as to achieve the desired discharge pressure based on the pressure detected by the second hydraulic sensor 36.

  In addition, the oil supply device returns oil passage 37 that returns oil leaking from the second oil requesting unit 20B (valve opening / closing mechanism 40) to the second oil storage unit 24 separately from the oil that falls through the crankcase 60. It has. The oil leaking from the valve opening / closing mechanism 40 is received by an oil sump partitioned from the region of the upper deck of the cylinder head 4 that receives the oil supplied to the first oil supply unit 20A. The return oil passage 37 extends from the oil reservoir to the second oil reservoir 24 through an oil drain hole dedicated to the oil reservoir that penetrates the cylinder head 4 and the cylinder block 3. That is, the return oil passage 37 is configured by a dedicated passage extending from the cylinder head 3 toward the second oil reservoir 24 so that the bubble-containing oil that collides with the counterweight 9 and scatters does not enter the return oil. .

  It should be noted that it is not necessary to directly connect the return oil passage 37 to the second oil reservoir 24 because it is sufficient that the bubble-containing oil does not enter the return oil.

  The first oil supply passage 26 and the second oil supply passage 33 are connected by an auxiliary oil passage 38 on the downstream side of the respective oil coolers 26 and 35. The auxiliary oil passage 38 allows the inflow of oil from the first oil supply passage 26 to the second oil supply passage 33 using the pressure difference between the oil passages, while the first oil supply from the second oil supply passage 33 is allowed. A check valve 39 for preventing the oil from flowing into the passage 26 is provided. When the oil pressure in the first oil supply passage 26 is higher than the oil pressure in the second oil supply passage 33, the check valve 39 is opened, and oil flows from the first oil supply passage 26 into the second oil supply passage 33. Even when the oil pressure in the second oil supply passage 33 is higher than the oil pressure in the first oil supply passage 26, the check valve 39 prevents the oil from flowing from the second oil supply passage 33 into the first oil supply passage 26. . The second oil demanding part 20B (valve opening / closing mechanism 40) has a required oil pressure higher than that of the first oil demanding part 20A. Normally, the auxiliary oil path 38 is not in a communicating state, and the auxiliary oil path 38 is not in communication. Supplies oil to the second oil requesting unit 20B using the first oil pump 21 when the second oil pump 22 cannot be driven when the second oil pump 22 fails or is extremely cold. Use for.

[About both the first and second oil reservoirs 23, 24]
As shown in FIG. 4, the first oil reservoir 23 and the second oil reservoir 24 are provided in the oil pan 5 in a partitioned manner. The second oil pump 22 is attached to the oil pan 5. The first oil reservoir 23 receives oil that drops from each part of the engine 1 (first oil request part 20A) through the crankcase 60 shown in FIG. As shown in FIGS. 5 and 6, the second oil reservoir 24 is provided with a lid 24 a so that the falling oil does not enter directly. In FIG. 4, 55 is an oil discharge hole from the second oil pump 22, and 56 and 57 are oil return holes for the second oil reservoir 24.

  As shown in FIG. 5, the oil pan 5 of the present embodiment is formed by integrally molding the first oil reservoir 23 and the main body (the portion excluding the lid 24a) of the second oil reservoir 24 by aluminum die casting. Is. That is, the partition wall 5 b that partitions the first oil reservoir 23 and the second oil reservoir 24 rises from the bottom wall 5 a of the oil pan 5. A 3D printer can also be adopted for the integral molding. Although the oil pan 5 made of aluminum alloy is used in the present embodiment, it may be made of resin for weight reduction and oil heat retention performance improvement.

  An oil drain hole 58 for the first oil reservoir 23 is provided in the lower part of the peripheral wall 5 c of the oil pan 5. The second oil reservoir 24 has an extension 24b having a small volume extending from the lower part of the partition wall 5b toward the oil drain hole 58 for the first oil reservoir 23, and the first oil reservoir 24 is provided at the tip of the extension 24b. An oil drain hole 59 for the second oil storage part 24 opposite to the oil drain hole 58 for the part 23 is provided. A common drain bolt 61 is fitted into both the oil drain holes 58 and 59.

  As shown in FIG. 6, a communication hole 62 is provided in the lower part of the partition wall 5 b as a communication part that communicates the first oil storage part 23 and the second oil storage part 24. The communication hole 62 is provided at a position lower than the minimum oil level of the first oil reservoir 23, that is, the oil level of the first oil reservoir 23 when the engine is stopped.

<About the control unit 100>
The control unit 100 is a control device based on a microcomputer, and inputs signals from various sensors or detection means for detecting the operating state of the engine 1, the remaining battery level, the amount of oil stored in the oil storage chamber 42, and the like. A signal input unit, a calculation unit that performs calculation processing related to control, a signal output unit that outputs a control signal to devices to be controlled (hydraulic control valve 43, oil pumps 21, 22, etc.), and a program necessary for control And a storage unit for storing data (such as a hydraulic control map).

  Here, the control unit 100 outputs a control signal so as to always operate with respect to the second oil pump 22 during operation of the engine 1, and operates the valve opening / closing mechanism 40 when the engine 1 is stopped. Therefore, in principle, the operation of the second oil pump 22 is stopped. Even if the operation of the second oil pump 22 is stopped, the engine 1 is started because oil is supplied from the oil storage chamber 42 to the main body of the valve opening / closing mechanism 40 in accordance with oil leakage in the main body. When this happens, the valve opening / closing mechanism 40 operates normally.

  However, if the engine 1 is stopped for a long period of time, as a result of the above replenishment, there is a possibility that the oil in the oil storage chamber 42 runs out and the main body of the valve opening / closing mechanism 40 becomes in an oil shortage state. The oil supply passage 33 may also be in a state where oil has been removed. In that case, even if the second oil pump 22 is activated when the engine 1 is started, the valve opening / closing mechanism 40 is not immediately filled with oil, and it takes time until it normally operates. That is, the startability of the engine is deteriorated.

  Therefore, in the present embodiment, the control unit 100 drives the second oil pump 22 assuming that the oil storage amount in the oil storage chamber 42 has decreased to a predetermined value or less when the engine 1 has been stopped for a predetermined time. Thus, oil is supplied to the oil storage chamber 42.

<Advantages of this embodiment>
Oil mixed with bubbles falls into the first oil reservoir 23 of the oil pan 5 by colliding with the counterweight 9 and splashing, but the oil mixed with the bubbles is covered with a lid 24a of the second oil reservoir 24. Therefore, the second oil reservoir 24 does not enter. Oil that does not substantially contain bubbles returning from the valve opening / closing mechanism 40 side through the return oil passage 37 enters the second oil reservoir 24, and bubbles near the bottom of the first oil reservoir 23 are substantially Oil that has not been mixed in only enters through the communication hole 62.

  Accordingly, it is possible to avoid the supply of oil mixed with bubbles to the valve opening / closing mechanism 40 side by driving the second oil pump 22. This is advantageous in opening and closing the intake valve 13 and the exhaust valve 14 with the desired opening / closing characteristics. Therefore, according to the engine operating state, CI combustion (compressed self-ignition combustion in which the air-fuel mixture is combusted by self-ignition) and SI combustion (spark ignition combustion in which the air-fuel mixture is ignited by the spark plug and combusted) are switched. In the engine, the internal EGR control by the opening / closing control of the intake valve 13 and the exhaust valve 14 can be performed precisely, and the engine CI combustion region can be easily expanded.

  Since the first oil storage part 23 and the second oil storage part 24 are provided in the oil pan 5, the second oil storage part indicates that the oil in the first oil storage part 23 flows when the vehicle is traveling on a slope or turning. 24 becomes a form to suppress. Therefore, in the first oil reservoir 23, it is possible to prevent the oil from being biased. Therefore, it is advantageous in avoiding that the oil strainer 25 of the first oil pump 21 is exposed from the oil in the first oil reservoir 23.

  Further, a common drain bolt 61 can be provided in both the oil reservoirs 23 and 24. Therefore, in oil exchange, oil can be extracted from both oil storage portions 23 and 24 by operating one drain bolt 61. Therefore, the oil change operation is simplified.

  Since the first oil storage portion 23 and the second oil storage portion 24 are integrally formed, the manufacturing cost can be reduced and the number of steps for assembling the main body of the engine 1 can be reduced. Further, since the partition wall 5b is provided in the oil pan 5 so as to partition the first oil storage portion 23 and the second oil storage portion 24, the rigidity of the oil pan 5 is increased, and the oil pan 5 resonates with respect to engine vibration. This is advantageous for suppressing (noise generation).

  When the second oil pump 22 fails during operation of the engine 1 or when the second oil pump 22 cannot be operated, the oil discharged from the first oil pump 21 is supplemented from the first oil supply passage 26. The valve 38 is supplied to the valve opening / closing mechanism 44 through the passage 38. Accordingly, it is possible to avoid a malfunction of the valve opening / closing mechanism 44.

<Other embodiments>
In the above embodiment, the drain bolt 61 common to both the oil reservoirs 23 and 24 is provided. However, an oil drain hole is provided close to each of the oil reservoirs 23 and 24, and a separate drain is provided for each oil drain hole. Bolts may be provided. Even in this case, since the oil drain holes of both the oil reservoirs 23 and 24 are close to each other, the oil change operation is easy.

  In the above-described embodiment, both the oil reservoirs 23 and 24 are communicated by the communication hole 62 provided in the partition wall 5b. However, as shown in FIG. 7, the bottom wall 24c of the second oil reservoir 24 is connected to the first oil reservoir. The oil pan 5 may be separated from the bottom surface of the oil pan 5 and a plurality of minute holes 24d as communication portions may be provided in the bottom wall 24c. As a result, by utilizing the suction force of the second oil pump 22, it is possible to introduce oil into the second oil reservoir 24 from the minute holes 24 d, in which almost no air bubbles present at the bottom of the first oil reservoir 23 are mixed. it can.

  In the above embodiment, the oil pan 5 having the first oil reservoir 23 and the second oil reservoir 24 are integrally formed. However, as shown in FIG. 8, the second oil reservoir 24 is separated from the oil pan 5. It may be a body. FIG. 8 shows an example in which the cylinder block 3 and the second oil reservoir 24 are integrally formed. According to this example, the wall surface rigidity of the cylinder block 3 is increased by the walls constituting the second oil reservoir 24, which is advantageous in reducing engine vibration.

  In the above embodiment, the oil in which the bubbles of the first oil reservoir 23 are mixed is supplied to the cam journal. However, in that case, the oil in which the bubbles are mixed from the cam journal is supplied by the return oil passage 37. There is a possibility of returning to the second oil reservoir 24. Therefore, the second oil supply passage 33 may be branched and the lubricating oil may be supplied to the cam journal by the second oil pump 22. According to this, since the oil without air bubbles is supplied to the cam journal, it is possible to reliably avoid the air bubbles from being mixed into the oil returning to the second oil reservoir 24 by the return oil passage 37. it can.

  In the above embodiment, a mechanical oil pump driven by the crankshaft 7 is employed as the first oil pump 21, but an electric oil pump may be employed.

DESCRIPTION OF SYMBOLS 1 Engine 3 Cylinder block 5 Oil pan 7 Crankshaft 20A 1st oil request | requirement part 20B 2nd oil request | requirement part 21 1st oil pump 22 2nd oil pump 23 1st oil storage part 24 2nd oil storage part 24d Minute hole (communication Part)
37 Return oil passage 40 Hydraulic drive variable valve opening / closing mechanism (hydraulic drive variable valve mechanism)
60 Crankcase 62 Communication hole (Communication part)

Claims (4)

An intake valve configured to be able to open and close the intake port provided in the cylinder;
An exhaust valve configured to open and close an exhaust port provided in the cylinder;
A hydraulically driven variable valve mechanism configured to be operable to open and close at least one of the intake valve and the exhaust valve;
An oil supply device for an engine equipped with
A first oil pump for supplying oil to a first oil demanding part of the engine;
A second oil pump for supplying oil to a second oil requesting unit including the hydraulically driven variable valve mechanism other than the first oil requesting unit;
A first oil that is provided as an oil supply source for the first oil pump, is attached to a lower part of a cylinder block of the engine, and receives falling oil that falls through a crankcase in which a crankshaft is disposed. A reservoir,
A second oil storage section that is partitioned from the first oil storage section by a wall and provided so that the falling oil does not directly enter as an oil supply source for the second oil pump;
A return oil path for returning the oil supplied to the second oil request unit to the second oil storage unit so that the falling oil is not mixed;
The wall that divides the first oil reservoir and the second oil reservoir is provided at a position lower than the minimum oil level in the first oil reservoir , and the oil is supplied from the first oil reservoir to the second oil reservoir. An engine oil supply apparatus comprising: a communication portion that communicates the first oil storage portion with the second oil storage portion so as to be supplied to the oil storage portion . In claim 1,
The engine oil supply device, wherein the first oil storage part and the second oil storage part are provided in an oil pan attached to a lower part of a cylinder block of the engine. In claim 1,
An oil supply apparatus for an engine, wherein an oil pan formed by integrally forming the first oil reservoir and the second oil reservoir is attached to a lower portion of the cylinder block of the engine. In claim 1,
The engine oil supply device, wherein the second oil reservoir is formed integrally with a cylinder block of the engine.