JPH11324697A - Engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To compactly lay out auxiliary machines around an engine main body by arranging an oil sump part formed of an oil pan in a low position of the engine main body and by minimizing the space occupied by the oil pan as small as possible in the engine mounted on a car body with its main body laid down and the whole height set as low as possible. SOLUTION: In a state where an engine main body 1 is laid down with the axial direction of a cylinder 31 set to the approximately horizontal direction, the cylinder head 2 of the engine main body 1, a cylinder block 3, and an oil pan 4 are connected together along the axial direction of the cylinder, and the oil pan 4 is offset downward from the central axis X of the cylinder so that an oil sump part 40 for temporally storing lubricant oil is projected downward.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of an engine mounted on a vehicle body with an engine body laid down so that an axial direction of a cylinder approaches a horizontal direction as much as possible.

[0002]

2. Description of the Related Art In order to mount an engine on a vehicle body with the overall height being as low as possible, the axial direction of a cylinder is substantially horizontal (including a case where the cylinder is slightly inclined with respect to the horizontal direction). (Horizontal engine) in which the engine body is mounted on the vehicle body with the engine body laid down, the oil sump for temporarily storing lubricating oil is located at a low position in the engine body. Is connected to the lower side of the cylinder block to form an oil pan.In such a horizontal engine, in order to keep the height of the entire engine including each auxiliary equipment low, It has been practiced to separate each accessory from the periphery of the engine body and drive each accessory in conjunction with an accessory belt via a drive shaft dedicated to the accessory.

[0003]

However, in the conventional horizontal engine as described above, a cylinder block is provided as in an engine in which the axial direction of the cylinder is vertical and an engine in which the axial direction of the cylinder is oblique. By connecting the oil pan to the cylinder block so as to cover the entire lower side of the cylinder block, instead of connecting the oil pan along the cylinder axis so as to close the lower end opening of the oil pan, Occupies a large space, which makes it difficult to lay out compact accessories around the engine body in a compact manner.

Therefore, in order to keep the height of the entire engine including the accessories at a low level, the accessories are separated from the periphery of the engine body, and each of the accessories is driven through a dedicated drive shaft or the like. In this case, it is necessary to adopt a structure in which the accessories are driven in conjunction with the accessory belts. In addition to the troublesome handling of the parts, special parts such as a drive shaft dedicated to the auxiliary equipment are required, which leads to an increase in the number of parts.

An object of the present invention is to solve the above-mentioned problems. More specifically, the present invention relates to an engine which is mounted on a vehicle body with the engine body being laid down so that the overall height is as low as possible. The oil reservoir formed by the oil pan is arranged at a low position in the engine body, and the space occupied by the oil pan is minimized.
An object of the present invention is to make it possible to lay out compact accessories around the engine body.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, according to the present invention, an engine body is arranged so that an axial direction of a cylinder is substantially horizontal. In the laid-down state, the cylinder head of the engine body, the cylinder block and the oil pan are connected along the axial direction of the cylinder, and the oil pan is biased downward from the center axis of the cylinder. An oil reservoir for storing the oil in the oil tank is projected downward.

In the engine described in the first aspect, as described in the second aspect, the cylinder block and the oil pan are connected by a joining surface in a direction substantially orthogonal to the axial direction of the cylinder. It is characterized by having.

Further, in the engine described in the first aspect, as described in the third aspect, the oil pan below the cylinder block caused by projecting the oil pan deviated downward from the center axis of the cylinder. In space,
A part of accessories installed around the engine body is arranged.

Further, in the engine described in claim 1, as described in claim 4, each of the accessories installed around the engine body includes a bell housing for accommodating a clutch. It is characterized in that it is arranged so as to substantially fit within the height range.

Further, in the engine described in the first aspect, as described in the fifth aspect, the crankshaft is offset below the center axis of the cylinder. .

Further, in the engine described in claim 1, as described in claim 6, the intake port of the intake port and the exhaust port of the exhaust port formed in the cylinder head are connected to the combustion chamber. It is characterized in that it is opened on the opposite end face of the cylinder head or on the lower face of the cylinder head.

Further, in the engine described in the first aspect, as described in the seventh aspect, the intake valve and the exhaust valve of each cylinder have the same axis as the axis of each valve and the axis of the cylinder. As described above, they are arranged side by side on a horizontal line.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the engine of the present invention will be described below with reference to the drawings.

An embodiment of the engine according to the present invention will be described.
FIG. 1 shows the structure of the engine body, and FIG.
3 shows the engine as viewed from the front end face side of the cylinder head along the line AA in FIG. 1, and FIG. 3 shows an arrangement state of auxiliary machines with respect to the engine body shown in FIG.

As shown in FIG. 1, the engine of this embodiment is installed with the engine body 1 lying down so that the axial direction of the cylinder (the central axis X of the cylinder) is substantially horizontal. In a horizontal four-cylinder engine, a cylinder head 2, a cylinder block 3, and an oil pan 4, which constitute an engine body 1, are integrally connected along a cylinder axis direction. (Hereinafter, the present embodiment will be described with the axial direction of the cylinder being the front-rear direction, the cylinder head 2 being the front, and the oil pan 4 being the rear.)

The cylinder head 2 of the engine body 1 is provided with one intake port 5 and one exhaust port 6 for each cylinder, and an intake valve 7 for opening and closing an opening of the intake port 5 on the combustion chamber side. One cam for driving each of the intake / exhaust valves of each cylinder with respect to an exhaust valve (not shown because it overlaps with the intake valve 7) that opens and closes the combustion chamber side opening of the exhaust port 6 The shaft 9 is arranged in a cam chamber 13 covered with a head cover 12 in a state where the shaft 9 is rotatably held by a bearing portion 10 integrally formed with the cylinder head 2 and a cam cap 11.

Intake port (upstream end) of intake port 5 of each cylinder
Is the front end face 2a of the cylinder head 2 outside the cam chamber 13.
The intake pipe 14 connected to the intake port of the intake port 5 is connected to the front end surface 2a of the cylinder head 2 so as to partially cover the head cover 12, and is provided on the upper surface side of the cylinder head 2. Each injector 15 for injecting fuel into each intake port 5 is installed by the formed injector mounting portion 16.

In this embodiment, an exhaust port (downstream end) of the exhaust port 6 of each cylinder is opened on the lower surface side of the cylinder head 2, and an exhaust pipe 17 connected to the exhaust port of the exhaust port 6. Is disposed below the cylinder head 2. As for the exhaust port 6 and the exhaust pipe 17 of each cylinder, as shown in FIG. 4, the exhaust port of the exhaust port 6 is opened to the front end face 2a of the cylinder head 2 and the exhaust pipe 17 is moved from the front side to the exhaust port 6. May be connected to the exhaust port.

The cylinder head 2 shown in FIG.
As shown in FIG. 3, a bolt hole 2 for connecting the head cover is formed in a portion of the front end surface 2a which is to be a joining surface with the head cover 12.
1 is formed, the front end face 2a is not covered with the head cover 12, the intake port of the intake port 5 of each cylinder is opened, and the ignition plug insertion hole 22 of each cylinder is opened. And a bolt hole 23 for connecting the intake pipe.

In the cam chamber 13 of the cylinder head 2, a retainer mounting portion 24 for the valve of each cylinder is formed at the center in the up-down direction and in a horizontal line along the cylinder arrangement direction. A blow-by gas passage 26 is opened at the upper end of the cam chamber 13, an oil drop hole 27 is opened at the lower end of the cam chamber 13, and a head bolt for connecting the cylinder head 2 to the cylinder block 3 is provided. The head bolt through hole 28 for letting through
It is formed so as to be located at substantially the same interval over the entire cylinder head 2.

In this embodiment, as shown in FIG. 1, the retainer mounting portion 24 of the valve formed in the cylinder head 2 has the valve stem insertion hole 25 in the front-rear direction (axial direction of the cylinder). The combustion chamber side (combustion chamber ceiling) 2b of the cylinder head 2 does not have a concave surface like the combustion chamber ceiling of a normal engine, and has a planar shape. Has become. (A concave surface is formed on the upper surface side of the piston 32.)

As shown in FIG. 1, the cylinder block 3 of the engine body 1 has a cylinder portion 3 for forming a cylinder 31 for slidably storing a piston 32.
a, a crankcase part 3b for forming a crank chamber 35 for accommodating the crankshaft 34, and a crankshaft 34.
And a bell housing portion 3c for accommodating a clutch (not shown) connected to the end of the crankcase portion 3c. In the present embodiment, the lower portion of the rear end of the crankcase portion 3b is an oil pan. 4, and extends downward as a downwardly projecting portion 3d for constituting an oil reservoir 40 for lubricating oil.

In the cylinder block 3, a connecting rod 33 and a crank pin 34a are attached to a partition 32e between the cylinders formed integrally with the crankcase 3b.
A crankshaft 34 connected via a crank arm 36 (and a crank arm) is rotatably mounted by a crank cap 36. In the present embodiment, the crankshaft 34 is located below the center axis X of the cylinder 31. Have been offset to be.

The cylinder block 3 is provided with a blow-by gas oil separator 38 above the cylinder portion 3a so as to communicate with a blow-by gas passage 37 formed in the cylinder block 3. The lower side of the portion 3b communicates with an oil passage (not shown) in the cylinder block 3,
An oil filter 42 for filtering lubricating oil is attached.

The oil pan 4 of the engine body 1 has a shape deviated downward with respect to the central axis X of the cylinder 31. The oil pan 4 covers the open end of the crankcase portion 3b of the cylinder block 3 to thereby reduce the crank angle. A chamber 35 is defined, and a downwardly projecting portion 3d of the cylinder block 3 constitutes an oil reservoir 40 for lubricating oil. A direction substantially orthogonal to the axial direction of the cylinder (the central axis X of the cylinder). Are connected to the cylinder block 3 by the joining surface of the cylinder block 3.

The lower part of the oil pan 4 and the cylinder block 3
The lubricating oil reservoir 40 formed by the downwardly projecting portion 3d of the oil pan 4 projects downward from the crank chamber 35 so that the lower end of the bell housing portion 3c and the lower end of the oil pan 4 are located at substantially the same position. The oil reservoir 40 is provided with a strainer 41 connected to the suction side of an oil pump (not shown).

FIG. 3 shows an arrangement state of each auxiliary machine with respect to the engine body 1 as described above. In this embodiment,
Water pump 43, alternator 44 and air conditioner 4
5 is driven by the rotation of an accessory driving pulley 48 fixed to the crankshaft 34 via an accessory belt 47 whose tension is adjusted by a tensioner 46 and a pulley of each accessory. , Are installed around the engine body 1.

In this embodiment, as shown in FIGS. 2 and 3, the oil filter 42 and the water filter are provided in a space below the cylinder block 3 generated by projecting the oil reservoir 40 of the lubricating oil downward. Pumps 43 are arranged respectively, and the alternator 44 and the air conditioner 45 are also provided.
The bell housing 3c of the engine body 1 is disposed so as to be substantially within the height range of the bell housing 3c.

According to the engine of the present embodiment having the above-described configuration, the engine body 1 is laid down so that the axial direction of the cylinder (the central axis X of the cylinder) is substantially horizontal, so that the height of the entire engine is increased. The oil reservoir 40 formed by the oil pan 4 (and the downwardly protruding portion 3d of the cylinder block 3) may be disposed at a low position of the engine body 1 when the oil pan 4 is mounted on the vehicle body in a state as low as possible. In addition, the space occupied by the oil pan 4 (oil reservoir 40) can be kept relatively small, and auxiliary equipment can be compactly installed around the engine body 1 as in a normal upright type engine. be able to.

Further, in the engine of the present embodiment, the cylinder block 3 and the oil pan 4 are connected by a joint surface in a direction substantially perpendicular to the axial direction of the cylinder, so that end processing of the cylinder block 3 is troublesome. It doesn't matter.

In the engine of the present embodiment, the crankshaft 34 is offset below the central axis X of the cylinder, so that the height of the engine body 1 in the lying state is lowered by the offset. can do.

In the four-stroke engine, the crankshaft is slightly offset from the center line of the cylinder in order to reduce the inclination angle of the connecting rod when the piston descends and reduce the side pressure of the piston acting on the cylinder wall. Although it has been conventionally performed, offsetting the crankshaft 34 below the central axis X of the cylinder 31 particularly in a horizontal engine produces the above-described specific effects.

In the engine according to the present embodiment, the oil filter 42 and the water pump 43 are provided in the space below the cylinder block 3 that is generated by biasing the oil pan 4 downward to project the oil reservoir 40 downward. Is arranged, the layout of the auxiliary equipment with respect to the engine main body can be made compact, and the alternator 44 and the air conditioner 45 are also substantially fitted within the height range of the bell housing 3c of the engine main body 1. By arranging the engine, the whole engine including the auxiliary equipment can be made compact and the mountability when the engine is mounted in a horizontal state can be improved.

Further, in the engine of the present embodiment, the intake port of the intake port 5 and the exhaust port of the exhaust port 6 formed in the cylinder head 2 are connected to the cylinder head end face 2 a opposite to the combustion chamber and the cylinder head 2. With the opening on the lower surface, it is possible to prevent the intake pipe 14 and the exhaust pipe 16 from being piped above the laid engine main body 1, thereby preventing the entire engine from becoming bulky in the vertical direction. The mountability when mounted in a horizontal state can be improved, and the injector 15 for fuel injection can be easily attached.

In the engine of this embodiment, the cylinder head 2 is formed by forming the retainer mounting portion 24 of the valve and the stem insertion hole 25 in the front-rear direction (axial direction of the cylinder). The diagonal machining at the time can be reduced, and the intake and exhaust valves of each cylinder are all arranged in a horizontal line.
By setting the axis of each valve in the front-rear direction (the direction of the axis of the cylinder), the vertical width of the cylinder head 2 when the engine body 1 is laid down can be made compact.

Further, in the engine of the present embodiment, since the combustion chamber ceiling 2b of the cylinder head 2 has a planar shape, the processing surface can be reduced, the processing cost can be reduced, and the combustion chamber side wall can be reduced. And the amount of intake air can be increased.

Although the embodiment of the engine of the present invention has been described above, the present invention is not limited to the specific structure as shown in the above embodiment. The installation angle may be set at an inclination angle having a slight angle from the horizontal direction according to the difference of the engine mounting location in the vehicle body. In the above embodiment, the oil pan 4 and the cylinder block Although the oil reservoir 40 is formed by the lower protruding portion 3d of the oil pan 3, the oil reservoir 40 can be formed only by the oil pan 4, and it is needless to say that the design can be changed as appropriate. Nor.

[0038]

According to the engine of the present invention as described above, the engine body is laid so that the axial direction of the cylinder is substantially horizontal, and the engine is mounted on the vehicle body with the height of the entire engine as low as possible. In such a case, the oil sump formed by the oil pan can be arranged at a low position of the engine body, and the space occupied by the oil sump formed by the oil pan can be relatively small, Auxiliary equipment can be compactly arranged around the engine body.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an internal structure of an engine main body according to an embodiment of the engine of the present invention.

FIG. 2 is a front view showing the engine as viewed from the front end surface side of the cylinder head along the line AA in FIG. 1;

FIG. 3 is an explanatory view showing an arrangement state of auxiliary machines with respect to the engine main body shown in FIG. 1;

FIG. 4 is a sectional view showing another example of the cylinder head and the intake / exhaust pipe of the engine body shown in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Engine main body 2 Cylinder head 3 Cylinder block 3c Bell housing 4 Oil pan 5 Intake port 6 Exhaust port 7 Intake valve 31 Cylinder 34 Crankshaft 40 Oil reservoir 42 Oil filter (auxiliary equipment) 43 Water pump (auxiliary equipment) 44 Alternator ( Auxiliary equipment) 45 Air conditioner (Auxiliary equipment) X Center axis of cylinder

Claims (7)

[Claims] 1. A cylinder head, a cylinder block, and an oil pan of an engine main body are connected along an axial direction of a cylinder in a state where the engine main body is laid so that an axial direction of the cylinder is substantially horizontal. Because the pan is deviated downward from the center axis of the cylinder,
An engine characterized in that an oil reservoir for temporarily storing lubricating oil is projected downward. 2. The engine according to claim 1, wherein the cylinder block and the oil pan are connected by a joint surface in a direction substantially perpendicular to the axial direction of the cylinder. 3. A part of auxiliary equipment installed around the engine body is arranged in a space below the cylinder block caused by projecting the oil pan so as to be deviated downward from the center axis of the cylinder. The engine according to claim 1, wherein: 4. The apparatus according to claim 1, wherein each of the accessories installed around the engine main body is disposed so as to substantially fit within a height range of a bell housing for housing the clutch. The engine described in. 5. The system according to claim 1, wherein the crankshaft is offset below the center axis of the cylinder.
The engine described in. 6. The cylinder head, wherein an intake port of an intake port and an exhaust port of an exhaust port formed in the cylinder head are opened on an end face of the cylinder head opposite to the combustion chamber or on a lower face of the cylinder head. Item 10. The engine according to Item 1. 7. The system according to claim 1, wherein the intake valve and the exhaust valve of each cylinder are arranged side by side so that the axis of each valve and the axis of the cylinder are in the same direction. The described engine.