JP4265178B2 - V-type internal combustion engine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a V-type internal combustion engine.
[0002]
[Prior art]
2. Description of the Related Art An in-line internal combustion engine in which a crankshaft center is offset from a center line of a cylinder bore (offset crank mechanism) has been conventionally known. (See Patent Document 1)
[0003]
[Patent Document 1]
JP-A-11-236832 (first to fourth pages, FIGS. 1 and 3)
[0004]
[Problems to be solved by the invention]
By the way, the present inventor has found that mounting of a V-type internal combustion engine on a vehicle can be improved by applying an offset crank mechanism to the V-type internal combustion engine. However, the conventional offset crank mechanism is applied to an in-line internal combustion engine, and no attempt has been made to apply the offset crank mechanism to a V-type internal combustion engine.
[0005]
[Means for Solving the Problems]
The present invention relates to a V-type internal combustion engine in which the cylinder bore center of at least one of the left and right banks is offset by a predetermined amount with respect to the crankshaft center. By offsetting in the direction opposite to the rotation direction, the space on the side of the crankshaft in the crankcase is expanded in the width direction of the cylinder block, and an oil pump is disposed in the space on the side of the expanded crankshaft. Above the shaft, an oil return means for receiving the return oil from the cylinder head side and guiding the return oil to the space side of the extended crankshaft is provided .
[0006]
According to the present invention, since the return oil from the cylinder head side is guided to the space side on the right side of the expanded crankshaft, it can be avoided that the return oil from the cylinder head side directly hits the crankshaft. Further, it is possible to prevent the return oil from being struck by the crankshaft from the cylinder head side, and it is possible to reduce friction when the crankshaft rotates.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
[0008]
FIG. 1 shows a comparative example of a V-type internal combustion engine according to the present invention. As shown in the figure, this V-type internal combustion engine includes a cylinder block 1 having a bank angle of, for example, 90 °, an oil pan 2 fixed to the lower portion of the cylinder block 1, and a left and right fixed to the upper portion of the cylinder block 1. The bank is generally composed of a pair of cylinder heads 9 and 9.
[0009]
A crankshaft 4 is disposed in a crankcase 3 defined by the cylinder block 1 and the oil pan 2. The crankshaft 4 rotates counterclockwise in FIG.
[0010]
In the cylinder block 1, the cylinder bore center lines P1 and P2 of the cylinders in both the left and right banks are offset by a predetermined amount with respect to the center of the crankshaft 4, that is, the crank main shaft center 4a. It is formed as follows.
[0011]
More specifically, the cylinder bore center line P1 is offset by a predetermined amount in a direction opposite to the rotation direction of the crankshaft 4 with respect to a straight line R1 passing through the crank main shaft center 4a and parallel to the cylinder bore center line P1. The cylinder bore center line P2 is offset by a predetermined amount in a direction opposite to the rotation direction of the crankshaft 4 with respect to a straight line R2 passing through the crank main shaft center 4a and parallel to the cylinder bore center line P2. Then, by offsetting the cylinder bore center lines P1 and P2 of the cylinders of the left and right banks with respect to the center of the crankshaft 4 in the direction opposite to the rotation direction of the crankshaft 4, the heights of the left and right banks are different. As a result, a step h occurs between the left and right banks, and the position of the crankshaft 4 in the crankcase 3 moves relatively to the left side in FIG. 1, while keeping the width of the crankcase 3 substantially constant, A space on the right side of the crankshaft 4 in the crankcase 3 is expanded in the width direction of the cylinder block 1.
[0012]
An oil pump 5 is disposed in the space on the right side of the expanded crankshaft 4. That is, the oil pump 5 is disposed in the crankcase 3 in a state offset from the crank spindle center 4a.
[0013]
The oil pan 2 constituting the lower part of the crankcase 3 is formed with a deep bottom portion 6 in which oil is stored and a shallow bottom portion 7 that is shallower than the deep bottom portion 6. The deep bottom portion 6 is located below the space on the right side of the expanded crankshaft 4. That is, in the oil pan 2, the oil in the oil pan 2 is mainly stored in the deep bottom portion 6, and the crank locus Q does not interfere with the oil level in the oil pan 2 by offsetting the deep bottom portion 6 from the crankshaft 4. It is formed as follows.
[0014]
Further, the bottom surface of the shallow bottom portion 7 is formed so as to be gradually inclined toward the deep bottom portion 6.
[0015]
The oil in the crankcase 3 stored in the deep bottom portion 6 is pumped up to the oil pump 5 via an oil strainer 8 disposed on the right side of the expanded crankshaft 4.
[0016]
The oil strainer 8 is roughly constituted by a head portion 8a disposed in the deep bottom portion 6 and an introduction passage portion 8b for introducing oil sucked and filtered by the head portion 8a into the oil pump 5.
[0017]
In the V-type internal combustion engine having the above-described configuration, the cylinder bore center lines P1 and P2 of the cylinders in both the left and right banks are offset with respect to the center of the crankshaft 4 in the direction opposite to the rotation direction of the crankshaft 4, thereby Therefore, when the hood line (hood line) covering the engine room of the vehicle is inclined, the inclined hood line can be efficiently used and mounted on the vehicle. That is, by using the step h between the left and right banks, the V-type internal combustion engine can be mounted on the vehicle according to the layout of the vehicle body.
[0018]
Further, the cylinder bore center lines P1 and P2 of the cylinders in both the left and right banks are offset from the center of the crankshaft 4 in the direction opposite to the rotation direction of the crankshaft 4, thereby expanding the cylinder block 1 without increasing its weight. A space on the right side of the crankshaft 4 can be secured.
[0019]
The deep bottom portion 6 of the oil pan 2 is positioned below the space on the right side of the expanded crankshaft 4 and the oil strainer 8 is disposed on the space side of the expanded crankshaft 4 on the right side. The oil can be stored only in the deep bottom portion 6 of the No. 2, so that the oil level of the crankshaft 4 can be prevented and the deep bottom portion 6 of the oil pan 2 can be made relatively shallow. That is, the overall height of the V-type internal combustion engine can be reduced as a whole.
[0020]
In addition, since the deep bottom portion 6 of the oil pan 2 can be made relatively shallow, the amount of circulating oil can be reduced.
[0021]
Further, since the deep bottom portion 6 of the oil pan 2 and the oil pump 5 are located on the right side of the extended crankshaft 4, the head portion 8 a of the oil strainer 8 can be brought close to the oil pump 5. In addition, the introduction passage 8b of the oil strainer 8 can be shortened, and the structure of the oil strainer 8 can be simplified as a whole.
[0022]
Since the crankshaft 4 and the deep bottom portion 6 of the oil pan 2 are offset, the baffle plate that has been conventionally required can be eliminated.
[0023]
In particular, since the deep bottom portion 6 of the oil pan 2 is located below the space on the right side of the expanded crankshaft 4 and oil is stored in the deep bottom portion 6, as shown in FIGS. In accordance with the vehicle hood line, the V-type internal combustion engine having the above configuration can be tilted and mounted on the vehicle. In other words, even when the V-type internal combustion engine having the above-described configuration is mounted on the vehicle at an angle, oil does not flow from the deep bottom portion 6 to the shallow bottom portion 7, so that oil hitting by the crankshaft 4 can be reliably prevented. it can.
[0024]
Since the oil pump 5 can be disposed in the space on the right side of the expanded crankshaft 4, the degree of freedom in the auxiliary machine layout is increased, and the V-type internal combustion engine having the above-described configuration is generally mounted on the vehicle. Can be improved.
[0025]
In addition, the V-type internal combustion engine having the above-described configuration can be mounted on the vehicle so that the step h between the left and right banks is eliminated.
[0026]
FIG. 2 shows a state in which the V-type internal combustion engine having the above-described configuration is mounted on an FR vehicle so that the crankshaft 4 is vertically placed along the vehicle front-rear direction and further tilted in the rotation direction of the crankshaft 4. As shown in FIG. 2, when the V-type internal combustion engine having the above configuration is mounted on a vehicle, the right bank in FIG. 2 is lifted relatively higher than the left bank in FIG. The minimum ground clearance, that is, the distance from the vehicle ground contact surface of the deep bottom portion 6 can be secured.
[0027]
FIG. 3 shows a state in which the V-type internal combustion engine having the above-described configuration is mounted on an FF vehicle so that the crankshaft 4 is placed sideways along the left-right direction of the vehicle and tilted in the direction opposite to the rotation direction of the crankshaft 4. Yes. As shown in FIG. 3, if the V-type internal combustion engine having the above configuration is mounted on a vehicle, the vehicle hood line can be further inclined, and the degree of freedom of design of the vehicle body can be secured.
[0028]
Further, when the V-type internal combustion engine having the above configuration is mounted horizontally on the FF vehicle, as shown in FIG. 3, the space on the right side of the expanded crankshaft 4 is located on the vehicle front side with respect to the crankshaft 4. Such mounting improves layout performance. In other words, when the V-type internal combustion engine having the above-described configuration is mounted in an engine room in which the vehicle hood line is inclined, the space on the right side of the expanded crankshaft 4 is on the inclined side of the vehicle hood line (FIG. 3). If it is mounted horizontally so that the bank on the lower side of the head (the bank on the right side in FIG. 3) is the inclined side of the vehicle hood line, the layout is good.
[0029]
Here, as a driving method of the oil pump 5 in the V-type internal combustion engine having the above-described configuration, a method of rotating the crankshaft 4 as shown in FIG. 4 and a rotation speed of the crankshaft 4 as shown in FIG. There is a method of rotationally driving with an external drive source 10 (oil pump driving means) such as an electric motor or a hydraulic motor whose rotational speed does not depend.
[0030]
When the oil pump 5 is rotationally driven by the external drive source 10 (see FIG. 5), the rotational speed of the oil pump 5 can always be set to the optimal rotational speed, and the V-type internal combustion is achieved by optimizing the oil circulation amount. There is an advantage that the friction of each engine can be reduced.
[0031]
Further, when the oil pump 5 is rotationally driven by the crankshaft 4 (see FIG. 4), the oil pump 5 is not located on the axis of the crankshaft 4, so that the power between the crankshaft 4 and the oil pump 5 is By disposing a clutch or the like in the transmission path, the oil pump 5 can be driven without being synchronized with the rotation speed of the crankshaft 4.
[0032]
Next, a description will be given real施例of the present invention. Real施例This is the V-type internal combustion engine of the comparative example described above, as shown in FIGS. 6 and 7, receives the return oil from the cylinder head side, and extended crankshaft 4 right side of the space side An oil return plate 20 is disposed above the crankshaft 4 as oil return means for guiding the return oil.
[0033]
More specifically, the oil return plate 20 has a substantially plate shape elongated along the longitudinal direction of the cylinder, and has a number of notches 21 corresponding to the number of cylinders so as not to interfere with the connecting rods (not shown) of each cylinder. .., 21 are formed, and are arranged in a state of being inclined to the space side on the right side of the expanded crankshaft 4, that is, to the right side in FIG. 7.
[0034]
In such an embodiment of the present invention, the return oil from the cylinder head side is guided by the oil return plate 20 to the space side on the right side of the expanded crankshaft 4, so that the crankshaft 4 is moved from the cylinder head side to the crankshaft 4. Of the return oil from the cylinder head can be prevented, and the oil hitting of the return oil from the cylinder head side by the crankshaft 4 can be prevented, and the friction when the crankshaft 4 rotates can be further reduced. .
[0035]
Also, oil mist in the crankcase 3 is reduced by preventing the crankshaft 4 from hitting the return oil from the cylinder head side. That is, since the amount of circulating oil can be further reduced, the depth of the deep bottom portion 6 of the oil pan 2 can be made shallower, and the overall height of the V-type internal combustion engine can be made smaller overall.
[0036]
In the above you施例, relative to the crank shaft 4 center, although offsetting left and right cylinder bore center P1, P2 of the cylinders of both banks in a direction opposite to the rotation direction of the crankshaft 4, the right bank Only the cylinder bore center P2 of the cylinder may be offset in the direction opposite to the rotation direction of the crankshaft 4.
[0037]
Further, when only the cylinder bore center of the cylinder of one bank is offset from the center of the crankshaft, it is advantageous when performing cylinder deactivation. In other words, cylinder deactivation is usually performed when the engine is under low load. At this time, if cylinder deactivation is performed with the cylinder bore center offset from the crankshaft center, piston friction with respect to the cylinder increases. Because it will end up.
[0038]
Further, V-type internal combustion engine in the above you施例, it is also possible to vertically mounted with respect to the vehicle.
[0039]
The technical idea of the present invention that can be grasped from the above embodiments will be listed together with the effects thereof.
[0040]
(1) In the V-type internal combustion engine, the center of the cylinder bore in at least one of the left and right banks is offset by a predetermined amount with respect to the center of the crankshaft. This makes it possible to improve the mountability of the V-type internal combustion engine on the vehicle by utilizing the fact that the heights of the left and right banks are different from each other and efficiently using the vehicle body shape.
[0041]
(2) In the V-type internal combustion engine, the cylinder bore centers of the cylinders of the left and right banks are offset by a predetermined amount with respect to the center of the crankshaft. This makes it possible to improve the mountability of the V-type internal combustion engine on the vehicle by utilizing the fact that the heights of the left and right banks are different from each other and efficiently using the vehicle body shape.
[0042]
(3) In the configuration described in (1) and (2) above, by offsetting the cylinder bore center in the direction opposite to the crankshaft rotation direction with respect to the crankshaft center, the space beside the crankshaft in the crankcase is The oil pump is extended in the width direction of the cylinder block, and an oil pump is disposed in the space beside the extended crankshaft. Thereby, the space beside the crankshaft can be expanded without increasing the width of the crankcase in the width direction of the cylinder block. In addition, since the oil pump can be disposed in the space beside the extended crankcase, the degree of freedom in the layout of the auxiliary equipment is increased, and the mountability to the vehicle can be improved.
[0043]
(4) In the configuration described in (3) above, the oil pan that forms the lower part of the crankcase has a deep bottom portion that stores oil and a shallow bottom portion that is relatively shallow with respect to the deep bottom portion. A deep bottom portion is located below the space on the side of the expanded crankshaft. Thereby, it is possible to prevent the oil level in the oil pan from being hit by the crankshaft.
[0044]
(5) In the configuration described in (3) or (4) above, the oil pump is driven to rotate by a crankshaft. As a result, the oil pump is not located on the center axis of the crankshaft, so the oil pump is driven without synchronizing with the rotation speed of the crankshaft by arranging a clutch or the like in the power transmission path between the crankshaft and the oil pump. It becomes possible.
[0045]
(6) In the configuration described in the above (3) or (4), the oil pump is rotationally driven by an oil pump driving means whose rotational speed does not depend on the rotational speed of the crankshaft. As a result, the rotation speed of the oil pump 5 can be set to the optimum rotation speed, and the friction of each friction part of the V-type internal combustion engine can be reduced by optimizing the oil circulation amount.
[0046]
(7) In the configuration according to any one of (4) to (6), the oil stored in the lower part of the crankcase is oil via an oil strainer disposed on the space side of the extended crankshaft. Pumped up by a pump. As a result, an oil reservoir (deep bottom) can be set only on the space side of the extended crankshaft, and oil level hit by the crankshaft can be prevented.
[0047]
(8) In the configuration according to any one of (3) to (7), the return oil from the cylinder head side is received above the crankshaft and returned to the space side of the extended crankshaft. An oil return means for guiding the oil is provided. Accordingly, it is possible to prevent the return oil from being struck by the crankshaft from the cylinder head side, and it is possible to reduce friction when the crankshaft rotates.
[0048]
(9) In the configuration described in any one of (1) to (8) above, the V-type internal combustion engine is mounted on the vehicle in a state where the V-type internal combustion engine is inclined at a predetermined angle so that the heights of the left and right banks are substantially coincident. Thereby, the mounting property to a vehicle can be improved.
[0049]
(10) In the configuration according to any one of (1) to (8), the V-type internal combustion engine is vertically mounted on the vehicle in a state where the V-type internal combustion engine is inclined at a predetermined angle so that the heights of both the left and right banks are substantially matched. . Thereby, the mounting property to a vehicle can be improved.
[0050]
(11) In the configuration described in any one of (3) to (8) above, the V-type internal combustion engine is mounted horizontally with respect to the vehicle so that the space beside the expanded crankshaft is on the vehicle front side. . Thereby, the mounting property to a vehicle can be improved.
[Brief description of the drawings]
FIG. 1 is a configuration explanatory diagram of a comparative example of a V-type internal combustion engine according to the present invention.
FIG. 2 is an explanatory diagram showing a comparative example of a V-type internal combustion engine according to the present invention that is placed horizontally while being inclined in the crankshaft rotation direction.
FIG. 3 is an explanatory diagram showing a comparative example of the V-type internal combustion engine according to the present invention, in which the V-type internal combustion engine is placed horizontally and inclined in the direction opposite to the crankshaft rotation direction.
FIG. 4 is an explanatory diagram showing an example in which an oil pump is rotationally driven by a crankshaft in a comparative example of a V-type internal combustion engine according to the present invention.
FIG. 5 is an explanatory diagram showing an example in which an oil pump is rotationally driven by an external drive source in a comparative example of a V-type internal combustion engine according to the present invention.
Explanatory view showing a V-type internal combustion institution in accordance with the present invention; FIG.
Explanatory view showing a V-type internal combustion institution in accordance with the present invention; FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Cylinder block 2 ... Oil pan 3 ... Crankcase 4 ... Crankshaft 5 ... Oil pump 6 ... Deep bottom part 7 ... Shallow bottom part 8 ... Oil strainer 9 ... Cylinder head 10 ... External drive source

Claims (8)

In the V-type internal combustion engine in which the center of the cylinder bore of at least one of the left and right banks is offset by a predetermined amount with respect to the crankshaft center,
By offsetting the cylinder bore center with respect to the crankshaft center in the direction opposite to the crankshaft rotation direction, the space beside the crankshaft in the crankcase is expanded in the width direction of the cylinder block. An oil pump is installed in the space ,
V-type internal combustion engine characterized in that oil return means for receiving return oil from the cylinder head side and guiding the return oil to the space side of the extended crankshaft is provided above the crankshaft. . The oil pan constituting the lower part of the crankcase is formed with a deep bottom portion in which oil is stored and a shallow bottom portion that is relatively shallow with respect to the deep bottom portion,
2. The V-type internal combustion engine according to claim 1, wherein a deep bottom portion is located below the space beside the expanded crankshaft.   The V-type internal combustion engine according to claim 1 or 2, wherein the oil pump is rotationally driven by a crankshaft.   3. The V-type internal combustion engine according to claim 1, wherein the oil pump is driven to rotate by an oil pump driving means whose rotation speed does not depend on the rotation speed of the crankshaft. 4.   The oil stored in the lower part of the crankcase is pumped up to an oil pump via an oil strainer disposed on the space side of the extended crankshaft. The V-type internal combustion engine described. The V-type internal combustion engine according to any one of claims 1 to 5 , wherein the V-type internal combustion engine is mounted on a vehicle in a state where it is inclined at a predetermined angle so that the heights of the left and right banks substantially coincide. The V-type internal combustion engine according to any one of claims 1 to 5 , wherein the V-type internal combustion engine is vertically mounted on a vehicle in a state where it is inclined at a predetermined angle so that the heights of both the left and right banks substantially coincide. The V-type internal combustion engine according to any one of claims 1 to 7 , wherein the V-type internal combustion engine is mounted horizontally with respect to the vehicle so that the space beside the extended crankshaft is on the vehicle front side.

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