engine

Abstract

The objective of this invention is to reduce the amount of pressure change inside the engine caused by the reciprocating motion of the piston. [Solution] The engine body has a first internal space for housing the crankshaft and a front section. The timing cover is attached to the front section of the engine body. The timing cover and the front section form a second internal space connected to the first internal space. The crankshaft protrudes forward from the timing cover by passing through the front section of the engine body and the timing cover in the front-rear direction. The rotating body is located in front of the timing cover and is fixed to the crankshaft. The timing cover includes a first projection located above the rotating body. The front end of the first projection is located in front of the front end of the rotating body.

Description

Technical Field

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[0001] The present invention relates to an engine.

Background Art

[0007] The second aspect is, The timing cover includes a second projection located below the rotating body, The front end of the second projection is located in front of the front end of the rotating body. This is the engine described on the first side. [Effects of the Invention]

[0008] According to the present invention, the amount of pressure change inside the engine caused by the reciprocating motion of the piston can be reduced. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a cross-sectional view of engine 10. [Figure 2] Figure 2 is a right-side view of the timing cover 22. [Figure 3] Figure 3 is a cross-sectional view of point AA in Figure 2. [Figure 4] Figure 4 is a front view of the timing cover 22. [Modes for carrying out the invention]

[0010] (Embodiment) [Structure of Engine 10] The structure of an engine 10 according to one embodiment of the present invention will be described below with reference to the drawings. Figure 1 is a cross-sectional view of the engine 10. Figure 1 is a cross-sectional view perpendicular to the left-right direction. Figure 2 is a right-side view of the timing cover 22. Figure 3 is a cross-sectional view at AA in Figure 2. Figure 4 is a front view of the timing cover 22. Hereinafter, the direction in which the central axis C0 of the crankshaft 14 extends is defined as the front-rear direction. The vertical direction is defined as the up-down direction. In this embodiment, the up-down direction coincides with the direction of movement of the piston 16a. The left-right direction is perpendicular to the front-rear direction and the up-down direction.

[0011] In this specification, X being positioned in front of Y means the following: X and Y are arranged in this order from front to back, and when viewed from behind, at least a portion of X overlaps with at least a portion of Y. In this specification, X being positioned in front of Y means the following: Define a virtual plane that includes the front end of Y and is orthogonal to the front-to-back direction. The entirety of X is positioned in front of the virtual plane. When viewed from behind, at least a portion of X may overlap with at least a portion of Y, or at least a portion of X may not overlap with at least a portion of Y. Note that while the front-to-back positional relationship has been explained, the left-to-right and up-to-down positional relationships are similar to the up-to-down positional relationship and will therefore not be explained.

[0012] In this specification, the front end of X means the point located furthest forward on X. The front end of X means the front end of X and the area surrounding the front end of X. The definitions of the rear end, left end, right end, upper end, and lower end are the same as those of the front end, so their explanation is omitted. The definitions of the rear end, left end, right end, upper end, and lower end are the same as those of the front end, so their explanation is omitted.

[0013] The engine 10 is, for example, a four-cycle single-cylinder engine. The engine 10 generates power for driving a four-wheel vehicle. However, the engine 10 may generate electric power for the generator by operating the generator to drive the vehicle. The engine 10 includes an engine body 12, a crankshaft 14, a piston 16a, a connecting rod 18a, a rotating body 20, and a timing cover 22.

[0014] The engine body 12 includes a cylinder head 12a, a cylinder block 12b, and an oil pan 12c. The cylinder head 12a, the cylinder block 12b, and the oil pan 12c are stacked in this order from top to bottom. A combustion chamber Sxa is formed in the cylinder head 12a. The combustion chamber Sxa has a conical shape. The combustion chambers Sxa are arranged in this order from the rear to the front.

[0015] The cylinder block 12b forms a cylinder Sya. The cylinder Sya has a cylindrical shape with a central axis extending in the vertical direction. Each of the cylinders Sya is connected to the combustion chamber Sxa.

[0016] The oil pan 12c forms a crank chamber SpA. The crank chamber SpA is located below the cylinder Sya. The crank chamber SpA is connected to the cylinder Sya.

[0017] Further, the oil pan 12c forms an oil storage chamber SpB. The oil storage chamber SpB is located below the crank chamber SpA. The oil storage chamber SpB is connected to the crank chamber SpA. An opening Op1 is provided at the front of the oil pan 12c.

[0018] The combustion chamber Sxa, the cylinder Sya, the crank chamber SpA, and the oil storage chamber SpB are included in the first internal space Sp1. Therefore, the engine body 12 forms a first internal space Sp1 for accommodating the crankshaft 14, the piston 16a, and the connecting rod 18a, which will be described later.

[0019] Furthermore, the engine body 12 has a front section 12f. The front section 12f is the part that forms the front of the engine body 12. The front section 12f includes the front section of the cylinder head 12a and the front section of the cylinder block 12b.

[0020] The timing cover 22 is attached to the front portion 12f of the engine body 12. Thus, the timing cover 22 and the front portion 12f form a second internal space Sp2. An opening Op1 is provided at the front of the oil pan 12c. Therefore, the second internal space Sp2 is connected to the first internal space Sp1 via the opening Op1. A timing mechanism (not shown) is located within the second internal space Sp2. The timing mechanism is a device for synchronizing the phase of the crankshaft 14 with the phase of the camshaft (not shown). The timing mechanism is, for example, a combination of a chain and multiple sprockets.

[0021] The crankshaft 14 is supported by the cylinder block 12b and the oil pan 12c. The crankshaft 14 protrudes forward from the timing cover 22 by passing through the front portion 12f of the engine body 12 and the timing cover 22 in the front-rear direction. The crankshaft 14 can rotate about the central axis C0.

[0022] The piston 16a is located within the cylinder Sya. The piston 16a has a cylindrical shape. The piston 16a can move upward and downward.

[0023] The connecting rod 18a connects the crankshaft 14 and the piston 16a. As a result, when the crankshaft 14 rotates, the piston 16a moves up and down.

[0024] The rotating body 20 is located in front of the timing cover. The rotating body 20 is fixed to the crankshaft 14. This allows the rotating body 20 to rotate together with the crankshaft around the central axis C0. The rotating body 20 is a pulley around which a belt is wound. When the rotating body 20 is rotated, the belt wound around the rotating body 20 rotates. The belt drives the auxiliary components of the engine 10. These auxiliary components include, for example, an alternator, a water pump, a compressor, etc.

[0025] Here, the timing cover 22 includes an intermediate portion 22a, a first projection 22b, and a second projection 22c. The first projection 22b, the intermediate portion 22a, and the second projection 22c are arranged in this order from top to bottom. The intermediate portion 22a is located behind the rotating body 20. As a result, the first projection 22b is located above the rotating body 20. The second projection 22c is located below the rotating body 20.

[0026] Furthermore, the intermediate portion 22a forms an intermediate space Spa. The first protrusion 22b forms a first protrusion space Spb. The second protrusion 22c forms a second protrusion space Spc. The intermediate space Spa, the first protrusion space Spb, and the second protrusion space Spc are contained within the second internal space Sp2.

[0027] The length of the first projection 22b in the front-rear direction is longer than the length of the intermediate portion 22a in the front-rear direction. As a result, the front end of the first projection 22b is located in front of the front end of the rotating body 20. Furthermore, the length of the first projection space Spb in the front-rear direction is longer than the length of the intermediate space Spa in the front-rear direction. As a result, the front end of the first projection space Spb is located in front of the front end of the rotating body 20.

[0028] Furthermore, the front end of the bottom surface Sb1 of the inner circumferential surface of the first projection 22b is located above the rear end of the bottom surface Sb1 of the inner circumferential surface of the first projection 22b. As a result, the bottom surface Sb1 is inclined.

[0029] Furthermore, a rib (not shown) is provided on the inner circumferential surface of the first protrusion 22b. This improves the rigidity of the first protrusion 22b. Also, as shown in Figures 2 and 4, a plurality of bosses 22d for fixing the timing cover 22 to the engine body 12 are provided on the outer circumferential surface of the first protrusion 22b. This improves the rigidity of the first protrusion 22b.

[0030] The length of the second protrusion 22c in the front-rear direction is longer than the length of the intermediate portion 22a in the front-rear direction. As a result, the front end of the second protrusion 22c is located in front of the front end of the rotating body 20. However, the front end of the second protrusion 22c is located behind the front end of the first protrusion 22b. Furthermore, the length of the second protrusion space Spc in the front-rear direction is longer than the length of the intermediate space Spa in the front-rear direction. As a result, the front end of the second protrusion space Spc is located in front of the front end of the rotating body 20. However, the front end of the second protrusion space Spc is located behind the front end of the first protrusion space Spb.

[0031] Furthermore, the front end of the bottom surface Sb2 of the inner circumferential surface of the second protrusion 22c is located above the rear end of the bottom surface Sb2 of the inner circumferential surface of the second protrusion 22c. As a result, the bottom surface Sb2 is inclined.

[0032] Furthermore, as shown in Figures 2 and 4, the outer circumferential surface of the second protrusion 22c is provided with a plurality of bosses 22d for fixing the timing cover 22 to the engine body 12. This improves the rigidity of the second protrusion 22c.

[0033] Furthermore, as shown in Figure 3, the width of the second protrusion 22c in the left-right direction decreases from the rear to the front.

[0034] In the engine 10 described above, oil 100 is provided in the oil storage chamber SpB and the second protruding space Spc.

[0035] [effect] According to engine 10, the amount of pressure change inside engine 10 caused by the reciprocating motion of piston 16a can be reduced. More specifically, when piston 16a reciprocates, the volume of the portion of the first internal space Sp1 located below piston 16a fluctuates. As a result, the pressure inside engine 10 changes periodically. Such pressure changes inside engine 10 can cause, for example, a decrease in sealing performance at the joint between cylinder block 12b and oil pan 12c.

[0036] Therefore, in engine 10, the timing cover 22 includes a first projection 22b. The first projection 22b is located above the rotating body 20. The front end of the first projection 22b is located in front of the front end of the rotating body 20. This increases the volume of space within the engine. This space within the engine includes a first internal space Sp1 and a second internal space Sp2. As a result, engine 10 can reduce the amount of pressure change within the engine 10 caused by the reciprocating motion of the piston 16a.

[0037] Furthermore, when the amount of pressure change inside the engine 10 caused by the reciprocating motion of the piston 16a is reduced, large waves are less likely to occur on the surface of the oil 100. As a result, the oil intake port (not shown) provided in the oil pan 12c is less likely to be exposed to the oil 100. Therefore, air is less likely to enter the oil line from the oil intake port.

[0038] Furthermore, in engine 10, the timing cover 22 includes a second projection 22c. The second projection 22c is located below the rotating body 20, and the front end of the second projection 22c is located in front of the front end of the rotating body 20. This increases the volume of space within the engine, which includes a first internal space Sp1 and a second internal space Sp2. As a result, engine 10 can reduce the amount of pressure change within the engine caused by the reciprocating motion of the piston 16a.

[0039] Furthermore, in the engine 10, the timing cover 22 includes a second projection 22c. The second projection 22c is located below the rotating body 20. The front end of the second projection 22c is located in front of the front end of the rotating body 20. This increases the volume of space that can accommodate the oil 100. As a result, the oil 100 is less likely to overheat, and the possibility of the oil 100 becoming too hot is reduced. Consequently, the degradation of the oil 100 is reduced.

[0040] Furthermore, in the engine 10, the timing cover 22 includes a second projection 22c. The second projection 22c is located below the rotating body 20. The front end of the second projection 22c is located in front of the front end of the rotating body 20. This increases the surface area of ​​the oil 100. As a result, large waves are less likely to form on the surface of the oil 100. Therefore, air is less likely to enter the oil line from the oil intake.

[0041] In this case, when the car is going around a corner, the engine 10 may tilt. If large waves are generated on the surface of the oil 100 in such a case, there is a high possibility that the oil intake port (not shown) provided in the oil pan 12c will be exposed to the oil 100. However, in the engine 10, large waves are unlikely to be generated on the surface of the oil 100, so air is unlikely to enter the oil line from the oil intake port.

[0042] Furthermore, the space above the rotating body 20 tends to become dead space. Therefore, in the engine 10, the first protrusion 22b is located above the rotating body 20. This promotes the effective use of space within the engine compartment.

[0043] Furthermore, the space below the rotating body 20 tends to become dead space. Therefore, in the engine 10, the second protrusion 22c is located below the rotating body 20. This promotes the effective use of space within the engine compartment.

[0044] Furthermore, the front end of the bottom surface Sb1 of the inner circumferential surface of the first protrusion 22b is located above the rear end of the bottom surface Sb1 of the inner circumferential surface of the first protrusion 22b. As a result, the bottom surface Sb1 is inclined. Therefore, the oil 100 falls into the first protrusion space Spb along the bottom surface Sb1. Consequently, the oil 100 flows into the oil pan 12c.

[0045] Furthermore, the front end of the bottom surface Sb2 of the inner circumferential surface of the second protrusion 22c is located above the rear end of the bottom surface Sb2 of the inner circumferential surface of the second protrusion 22c. As a result, the bottom surface Sb2 is inclined. Consequently, the oil 100 flows into the oil pan 12c.

[0046] (Other embodiments) The engine according to the present invention is not limited to engine 10, but can be modified within the scope of its gist.

[0047] The timing mechanism may be a combination of multiple gears, or a combination of multiple gears and a belt.

[0048] The engine 10 may have one cylinder or multiple cylinders. However, if the number of cylinders is small, the pressure fluctuations within the engine 10 will be large. Therefore, it is preferable that the number of cylinders in the engine 10 be small, such as two. [Explanation of Symbols]

[0049] 10: Engine 12: Engine body 12a: Cylinder head 12b: Cylinder block 12c: Oil pan 12f: Front part 14: Crankshaft 16a: Piston 18a: Connecting rod 20: Solid of revolution 22: Timing cover 22a: Middle part 22b: First protrusion 22c: Second protrusion 100: Oil C0: Center axis line Op1: Opening Sb1, S1b: Bottom surface Sp1: 1st internal space Sp2: 2nd internal space SpA: Crank chamber SpB: Oil containment chamber Spa: Intermediate space Spb: 1st protruding space Spc: 2nd protruding space Sxa: Combustion chamber Sya: Cylinder

Claims

1. An engine consists of an engine body, a crankshaft, a timing cover, and a rotating body. The direction in which the central axis of the crankshaft extends is defined as the front-to-back direction. The engine body has a first internal space for housing the crankshaft and a front section. The timing cover is attached to the front portion of the engine body. The timing cover and the front portion form a second internal space connected to the first internal space. The crankshaft extends forward from the timing cover by penetrating the front portion of the engine body and the timing cover in the front-rear direction. The rotating body is located in front of the timing cover and is fixed to the crankshaft. The timing cover includes a first projection located above the rotating body, The front end of the first projection is located in front of the front end of the rotating body. engine.

2. The timing cover includes a second projection located below the rotating body, The front end of the second projection is located in front of the front end of the rotating body. The engine according to claim 1.

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