CN210768968U

CN210768968U - Cover structure of internal combustion engine

Info

Publication number: CN210768968U
Application number: CN201921130225.3U
Authority: CN
Inventors: 小杉裕太郎; 和田壮大郎
Original assignee: Suzuki Motor Corp
Current assignee: Suzuki Motor Corp
Priority date: 2018-07-20
Filing date: 2019-07-18
Publication date: 2020-06-16
Anticipated expiration: 2029-07-18
Also published as: DE102019210463A1; FR3084108A1; JP7107054B2; JP2020012452A; FR3084108B1

Abstract

Provided is a cover structure for an internal combustion engine, which can reduce vibration of a hydraulic control valve mounted on a cover member and can improve the reliability of the hydraulic control valve. The engine (5) has a chain cover (18) attached to an end of an engine body (7), and the chain cover (18) is provided with: an oil passage section (24) that bulges out from the connecting wall (19) toward the engine body (7), extends in the vertical direction of the chain cover (18), and has an oil passage (24 a); and an oil passage portion (25) that bulges out from the connecting wall (19) toward the engine body (7), is connected to the side walls (19A, 19B) and the upper end of the oil passage portion (24), and has an oil passage (25 a). The cylinder section (27) has a wall section (27A) connected to a wall section (25A) of the oil passage section (25), and the cylinder section (27) extends along the oil passage section (25).

Description

Cover structure of internal combustion engine

Technical Field

The present invention relates to a cover structure for an internal combustion engine mounted on a vehicle.

Background

As an internal combustion engine mounted on a vehicle, an internal combustion engine is known that includes a covering member (chain cover) covering a timing chain and an oil control valve mounted on the covering member and supplying oil for operating a variable valve timing device (see patent document 1).

In this internal combustion engine, an engine mount bracket portion is provided at an upper portion of the cover member, and the internal combustion engine is supported by the vehicle body via the engine mount bracket portion. The oil control valve is provided adjacent to the engine mount bracket portion at a height position substantially equal to that of the engine mount bracket, and an oil passage communicating with the oil control valve is formed inside the cover member.

Documents of the prior art

Patent document

Patent document 1: japanese unexamined patent application publication No. 2005-320974

SUMMERY OF THE UTILITY MODEL

Problem to be solved by utility model

In such a conventional internal combustion engine, since the oil control valve is provided adjacent to the engine mount bracket portion at a height position substantially equal to the height position of the engine mount bracket portion, there is a possibility that the oil control valve vibrates due to vibration transmitted from the internal combustion engine to the vehicle body.

However, in patent document 1, since an installation structure of the oil control valve suitable for reducing vibration of the oil control valve is not considered, there is still room for improvement.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a cover structure of an internal combustion engine capable of reducing vibration of a hydraulic control valve attached to a cover member and improving reliability of the hydraulic control valve.

Means for solving the problems

The utility model discloses a cover structure of internal-combustion engine of 1 st constitution possesses: an engine main body having a crankshaft, a camshaft, and a variable valve mechanism that changes a relative rotational phase of the camshaft with respect to the crankshaft; a cover member having a pair of side walls fixed to end portions of the engine main body, a connecting wall provided between the pair of side walls and covering the end portions of the engine main body and connecting the pair of side walls, and a mounting fitting portion provided on an upper portion of the connecting wall and adapted to fit a mounting member provided on a vehicle body side; and a hydraulic control valve having a valve portion for supplying oil for operating the variable valve mechanism, wherein the cover member includes: a cylinder portion that bulges from the connecting wall to a side opposite to the engine body, is provided below the mount mounting portion, and is inserted into the valve portion; a 1 st cylinder portion that bulges out from the connecting wall toward the engine main body and extends in the vertical direction of the cover member; a 2 nd cylindrical portion that bulges out from the connecting wall toward the engine main body and is connected to the pair of side walls and an upper end of the 1 st cylindrical portion; and an inlet oil passage that supplies oil to the hydraulic cylinder section, the inlet oil passage including: a 1 st oil passage formed inside the 1 st cylinder part; and a 2 nd oil passage formed inside the 2 nd cylindrical portion and communicating with the 1 st oil passage and the cylinder portion, the cylinder portion having a wall portion connected to a wall portion of the 2 nd cylindrical portion and extending along the 2 nd cylindrical portion.

The cover structure of the internal combustion engine according to claim 2 is the cover structure of the internal combustion engine according to claim 1, wherein the cover member has a boss portion having one end connected to the cylinder portion and the other end connected to the engine main body, and the boss portion has an outlet oil passage for supplying oil from the hydraulic control valve to the variable valve mechanism and is connected to the 2 nd cylindrical portion.

A cover structure of an internal combustion engine according to claim 3 is the cover structure of the internal combustion engine according to claim 2, wherein a 3 rd cylindrical portion is provided on the connecting wall, the 3 rd cylindrical portion has a discharge oil path for discharging oil from the cylinder portion to a space between the cover member and the engine main body, and the 3 rd cylindrical portion is connected to the 2 nd cylindrical portion on a side opposite to the boss portion.

The cover structure of the internal combustion engine according to claim 4 of the present invention is the cover structure of the internal combustion engine according to any one of the configurations 1 to 3, wherein the cylinder portion is connected to the 2 nd cylindrical portion by a plate-shaped rib having the same thickness as the diameter of the 2 nd cylindrical portion.

Effect of the utility model

Thus, according to the present invention, the vibration of the hydraulic control valve attached to the cover member can be reduced, and the reliability of the hydraulic control valve can be improved.

Drawings

Fig. 1 is a front view of a powertrain of an embodiment of the present invention.

Fig. 2 is a perspective view of a chain cover according to an embodiment of the present invention.

Fig. 3 is an outside view (right side view) of the chain cover according to the embodiment of the present invention.

Fig. 4 is an inside view (left side view) of the chain cover according to the embodiment of the present invention.

Fig. 5 is a plan view of a chain cover according to an embodiment of the present invention.

Fig. 6 is a front view of a chain cover according to an embodiment of the present invention.

Fig. 7 is an enlarged view of an inner upper portion of the chain cover according to the embodiment of the present invention.

Fig. 8 is a sectional view taken along line VIII-VIII of fig. 7.

Fig. 9 is a view in section from direction IX-IX of fig. 7.

Fig. 10 is a cross-sectional view taken along the X-X direction of fig. 7.

Fig. 11 is a cross-sectional view taken in the direction XI-XI of fig. 7.

Description of the reference numerals

2L: left side member (vehicle body); 2R: a right side member (vehicle body); 3R: a right vibration-proof mounting part (mounting member); 5: an engine (internal combustion engine); 7: an engine main body; 10: an exhaust camshaft (camshaft); 11a, 12 a: a right end portion (end portion of the engine main body); 15: a crankshaft; 18: a chain cover (cover member); 19: a connecting wall; 19A, 19B: a side wall; 19E: ribs (plate-shaped ribs); 19 g: an oil passage (inlet oil passage); 22: a mounting member mounting section; 24: an oil passage portion (1 st cylinder portion); 24 a: an oil passage (1 st oil passage, inlet oil passage); 25: an oil passage portion (2 nd cylindrical portion); 25A: a wall portion (wall portion of the 2 nd cylindrical portion); 25 a: an oil passage (2 nd oil passage, inlet oil passage); 27: a hydraulic cylinder section; 27A: a wall portion (wall portion of the cylinder portion); 28: a hydraulic control valve; 28A: a spool (valve section); 30: a boss portion; 30c, 30 d: an outlet oil path; 35A, 35B: a tube part (3 rd tube part); 35a, 35 b: a discharge oil path; 53: an exhaust-side variable valve mechanism (variable valve mechanism); 54: a space (a space between the cover member and the engine main body).

Detailed Description

The utility model discloses an embodiment's cover structure of internal-combustion engine possesses: an engine main body having a crankshaft, a camshaft, and a variable valve mechanism that changes a relative rotational phase of the camshaft with respect to the crankshaft; a cover member having a pair of side walls fixed to an end portion of the engine main body, a connecting wall provided between the pair of side walls and covering the end portion of the engine main body, the pair of side walls being connected, and a mounting piece attachment portion provided on an upper portion of the connecting wall for attaching a mounting member provided on a vehicle body side; and a hydraulic control valve having a valve portion and supplying oil for operating the variable valve mechanism, wherein the cover member includes: a cylinder portion bulging from the connecting wall to a side opposite to the engine body and provided below the mount fitting portion for inserting the valve portion; a 1 st cylinder portion that bulges out from the connecting wall toward the engine body and extends in the vertical direction of the cover member; a 2 nd cylindrical portion bulging from the connecting wall toward the engine body and connected to the pair of side walls and an upper end of the 1 st cylindrical portion; and an inlet oil path that supplies oil to the hydraulic cylinder portion, the inlet oil path including: a 1 st oil path formed inside the 1 st cylinder part; and a 2 nd oil passage formed inside the 2 nd cylindrical portion and communicating with the 1 st oil passage and the cylinder portion, the cylinder portion having a wall portion connected to a wall portion of the 2 nd cylindrical portion and extending along the 2 nd cylindrical portion.

This reduces vibration of the hydraulic control valve attached to the cover member, and improves reliability of the hydraulic control valve.

[ examples ]

Hereinafter, an embodiment of a cover structure of an internal combustion engine according to the present invention will be described with reference to the drawings.

Fig. 1 to 11 are diagrams showing a cover structure of an internal combustion engine according to an embodiment of the present invention. In fig. 1 to 11, regarding the up-down, front-back, and left-right directions, when the direction in which the vehicle travels is defined as front and the direction in which the vehicle retreats is defined as rear, the width direction of the vehicle is the left-right direction, and the height direction of the vehicle is the up-down direction.

First, the configuration is explained.

In fig. 1, a vehicle 1 includes a left side member 2L and a right side member 2R. The left side member 2L and the right side member 2R are separated in the width direction of the vehicle 1 (hereinafter referred to as the vehicle width direction) and extend in the front-rear direction. The left longeron 2L and the right longeron 2R of this embodiment constitute the utility model discloses an automobile body.

Left and right vibration-proof mounting members 3L and 3R are provided on the left and right side members 2L and 2R, respectively. The left and right vibration-proof mounting members 3L and 3R are joined to the power train 4, and the power train 4 is elastically supported to the left and right side members 2L and 2R by the left and right vibration-proof mounting members 3L and 3R.

The power train 4 includes an engine 5 and a transmission 6 as internal combustion engines, and the engine 5 and the transmission 6 are arranged inside the left side member 2L and the right side member 2R in the vehicle width direction. The engine 5 converts thermal energy into mechanical energy, and the transmission 6 changes the rotational speed of the engine 5 and outputs the changed rotational speed.

The engine 5 includes an engine body 7, and the engine body 7 includes a cylinder block 11, a cylinder head 12, a head cover 13, and an oil pan 14.

A chain cover 18 (see fig. 2 and 3) is attached to the

right end portions

11a and 12a of the cylinder block 11 and the cylinder head 12 and the right end portion, not shown, of the cylinder head cover 13, the chain cover 18 covers the timing chain 8 from the right, and the timing chain 8 is provided to the

right end portions

11a and 12a of the cylinder block 11 and the cylinder head 12 and the right end portion of the cylinder head cover 13.

The chain cover 18 of the present embodiment constitutes a cover member of the present invention, and the

right end portions

11a and 12a of the vehicle width direction of the cylinder block 11 and the cylinder head 12 and the right end portion of the cylinder head cover 13 constitute end portions of the engine main body of the present invention. Hereinafter, the

right end portions

11a and 12a of the cylinder block 11 and the cylinder head 12 in the vehicle width direction and the right end portion of the head cover 13 are referred to as the right end portion of the engine body 7.

The cylinder block 11 is provided with a plurality of cylinders, not shown. The cylinder houses a piston, not shown, which reciprocates in the vertical direction relative to the cylinder. The pistons are coupled to a crankshaft 15 (see fig. 3) by a connecting rod (not shown), and the reciprocating motion of the pistons is converted into rotational motion of the crankshaft 15 by the connecting rod.

In fig. 1, the rotation center axis of the crankshaft 15 is indicated by a broken line. The crankshaft 15 extends in the vehicle width direction, and the engine 5 is a horizontal engine.

The cylinder head 12 is provided with: a plurality of air inlets not shown; a plurality of intake valves, not shown, that open and close the intake ports; a plurality of air outlets not shown; and a plurality of exhaust valves 10V (indicated by broken lines in fig. 1) that open and close the exhaust ports. The intake port introduces air into the cylinder, and the exhaust port exhausts exhaust gas burned in the cylinder from the cylinder.

The exhaust valve 10V and the intake valve are provided in 2 numbers respectively with respect to 1 cylinder, and the engine 5 of the present embodiment is constituted by a 4-cylinder engine, for example. Further, the number of cylinders is not limited to 4 cylinders.

A valve chamber, not shown, is formed between the cylinder head 12 and the cylinder head cover 13, and the intake camshaft 9 and the exhaust camshaft 10 shown in fig. 4 are housed in the valve chamber.

In fig. 4, a crank sprocket 15A is provided at an end portion of the crankshaft 15, and an intake cam sprocket 9A and an exhaust cam sprocket 10A are provided at end portions of the intake camshaft 9 and the exhaust camshaft 10, respectively.

A timing chain 8 is wound around the crank sprocket 15A, the intake cam sprocket 9A, and the exhaust cam sprocket 10A, and the crankshaft 15, the intake camshaft 9, and the exhaust camshaft 10 are coupled by the timing chain 8. Thereby, the power of the crankshaft 15 is transmitted to the intake camshaft 9 and the exhaust camshaft 10 through the timing chain 8.

The intake camshaft 9 is provided on the rear side with respect to the exhaust camshaft 10, and an intake variable valve mechanism 51 is provided at an end portion of the intake camshaft 9. In fig. 2 and 3, an electric actuator 52 is attached to the chain cover 18.

The intake variable valve mechanism 51 is driven by the electric actuator 52, and thereby changes the relative rotational phase of the intake camshaft 9 with respect to the crankshaft 15 to the retard side and the advance side, and changes the opening/closing timing of the intake valve to the advance side and the retard side.

In fig. 4, an exhaust variable valve mechanism 53 is provided at an end portion of the exhaust camshaft 10, and the exhaust variable valve mechanism 53 includes an advance chamber and a retard chamber, not shown, into which oil is introduced.

When oil is introduced into the advance chamber, the exhaust variable valve mechanism 53 changes the relative rotational phase of the exhaust camshaft 10 with respect to the crankshaft 15 to the advance side, and changes the opening/closing timing of the exhaust valve 10V to the advance side. When oil is introduced into the retard chamber, the exhaust variable valve mechanism 53 changes the relative rotational phase of the exhaust camshaft 10 with respect to the crankshaft 15 to the retard side, and changes the opening/closing timing of the exhaust valve 10V to the retard side. The exhaust camshaft 10 of the present embodiment constitutes the camshaft of the present invention, and the exhaust side variable valve mechanism 53 constitutes the exhaust valve mechanism of the present invention.

The oil pan 14 stores oil for lubricating the crankshaft 15, the pistons, and the like, or for operating the exhaust variable valve mechanism 53.

As shown in fig. 4 and 7, the chain cover 18 has a connecting wall 19 and

side walls

19A and 19B. As shown in fig. 5,

flange portions

19A, 19B are formed at the tips of the

side walls

19A, 19B, i.e., on the engine body 7 side, and the

flange portions

19A, 19B are fastened to the right end portion of the engine body 7 by bolts 20A. The

side walls

19A and 19B of the present embodiment include

flange portions

19A and 19B.

The connecting wall 19 is provided between the

side walls

19A, 19B, covers the right end portion of the engine body 7, and connects the

side walls

19A, 19B.

In fig. 2 and 3, a mounting piece fitting portion 22 is provided on an upper portion of a surface 19f of the connecting wall 19. In fig. 1, the mount fitting portion 22 bulges out to the right anti-vibration mounting member 3R from the surface 19f of the connecting wall 19, and the arm portion 3B of the right anti-vibration mounting member 3R is fitted to the upper surface of the mount fitting portion 22.

The right vibration-proof mounting member 3R has: a mounting member body 3A that houses an elastic body such as rubber, not shown, and is attached to the right side member 2R; and an arm portion 3B extending from the mounting member main body 3A to the mount fitting portion 22, fixed to the mount fitting portion 22 by a bolt 20B.

The engine 5 is elastically supported by the right side member 2R via the right vibration-proof mounting member 3R in a state suspended by the right vibration-proof mounting member 3R. The right anti-vibration mounting member 3R of the present embodiment constitutes a mounting member of the present invention.

In fig. 3 and 4, an oil pump section 23 is provided at a lower portion of the chain cover 18. The oil pump section 23 has: a bulging portion 33 bulging from the surface 19f of the connecting wall 19 to the right vibration-proof mounting member 3R side; and a pump housing 23A fitted to the back surface 19r of the connecting wall 19 so as to match the bulge portion 33.

The oil pump section 23 includes an oil pump 23B (indicated by a broken line in fig. 4) housed in the bulging section 33 and the pump housing 23A and rotatable. A suction port and a discharge port, not shown, are formed between the pump casing 23A and the connecting wall 19.

The oil pump 23A includes: an inner rotor, not shown, which is attached to the crankshaft 15 and is rotationally driven by the crankshaft 15; and an outer rotor, not shown, disposed radially outward so as to surround the inner rotor.

The oil pump 23A is a trochoid oil pump, for example, and internal teeth formed on the outer rotor and external teeth formed on the inner rotor are in contact with each other, so that a working chamber, not shown, that stores oil is formed between the external teeth and the internal teeth.

In the oil pump 23A, the power of the crankshaft 15 is transmitted to the inner rotor, whereby the inner rotor and the outer rotor rotate in one direction. At this time, the volume of the working chamber is increased and decreased continuously, whereby the oil stored in the oil pan 14 is sucked from the suction port and the sucked oil is discharged from the discharge port.

In fig. 4,

oil passage portions

24 and 25 are integrally formed in the chain cover 18. The oil passage portion 24 is formed in a cylindrical shape so as to bulge outward from the front surface 19f of the connecting wall 19 toward the right vibration isolating mounting member 3R (see fig. 3) and bulge inward toward the engine main body 7 from the rear surface 19R of the connecting wall 19.

An oil passage 24a (see fig. 8) is formed in the oil passage portion 24, and oil discharged from a discharge port of the oil pump portion 23 is introduced into the oil passage 24 a. The oil passage portion 24 extends upward from the oil pump portion 23 side, and is coupled to a lower portion of the mount fitting portion 22.

As shown in fig. 3, the oil passage portion 24 is adjacent to the side wall 19B and extends along the side wall 19B, being offset to the front side in the front-rear direction from the oil pump portion 23.

In fig. 4, the oil passage portion 25 is formed in a cylindrical shape bulging inward from the back surface 19r of the connecting wall 19. The oil passage portion 25 is coupled to an upper end of the oil passage portion 24. The oil passage portion 25 extends in the width direction of the connecting wall 19 from the upper end of the oil passage portion 24 toward the

side walls

19A, 19B, and is connected to the

side walls

19A, 19B.

The oil passage portion 25 extends in the width direction of the chain cover 18 from the end portion on the attachment fitting portion 22 side along the lower portion of the attachment fitting portion 22.

Thus, the oil passage portion 25 is connected to the upper end of the oil passage portion 25, the side wall 19A, and the side wall 19B.

In fig. 4 and 9, an oil passage 25a is formed inside the oil passage portion 25, and the oil passage 25a communicates with the oil passage 24 a. The oil passage portion 24 of the present embodiment constitutes the 1 st cylinder portion of the present invention, and the oil passage portion 25 constitutes the 2 nd cylinder portion of the present invention. The oil passage 24a constitutes a 1 st oil passage of the present invention, and the oil passage 25a constitutes a 2 nd oil passage of the present invention.

In fig. 2 and 3, a cylinder portion 27 is provided above the connecting wall 19. The cylinder portion 27 bulges out from the surface 19f of the connecting wall 19 toward the right anti-vibration mounting member 3R opposite to the engine body 7.

The cylinder portion 27 is provided on the lower side of the mount fitting portion 22, and is coupled to the mount fitting portion 22. A hydraulic control valve 28 is inserted into the hydraulic cylinder section 27.

As shown in fig. 9, the hydraulic control valve 28 includes: a spool valve 28A inserted into the cylinder section 27; and a control unit 28B such as an electromagnetic solenoid that projects outward from the cylinder unit 27 and drives the spool valve 28A.

The cylinder portion 27 has a wall portion 27A connected to the wall portion 25A of the oil passage portion 25, and the cylinder portion 27 extends in the front-rear direction along the oil passage portion 25. In other words, the cylinder portion 27 and the oil passage portion 25 are adjacent to each other at the same height position in the vehicle width direction by the

wall portions

27A, 25A.

An oil passage 19g is formed in the connecting wall 19. The oil passage 19g communicates between the oil passage 25a and the cylinder section 27, and the oil flowing through the oil passage 25a is introduced into the cylinder section 27 through the oil passage 19 g. The oil passage 19g and the

oil passages

24a and 25a of the present embodiment constitute an inlet oil passage of the present invention.

In fig. 3, a bulge 29 is provided on a surface 19f of the connecting wall 19. The bulging portion 29 bulges to the right vibration damping mounting member 3R from the surface 19f of the connecting wall 19 (see fig. 1), and is coupled to the lower portion of the cylinder portion 27. The bulging portion 29 extends in the width direction of the chain cover 18 and connects the oil passage portion 24 and the flange portion 19 a.

In fig. 4 and 7, a boss portion 30 is provided on a back surface 19r of the connecting wall 19. In fig. 10, one end of the boss portion 30 is joined to the cylinder portion 27, and the other end is joined to the cylinder head 12. In fig. 10, the cylinder head 12 to which the other end of the boss portion 30 is joined is shown by a broken line.

A through hole 30a through which a bolt 20C (see fig. 5) is inserted is formed in an upper portion of the boss portion 30, and the boss portion 30 is fastened to the cylinder head 12 by the bolt 20C. The lower portion of the boss portion 30 is joined to the oil passage portion 25, and the front side surface of the boss portion 30 is joined to the peripheral portion of the mount fitting portion 22.

In fig. 7 and 9, a lubricating oil passage 30b is provided in the boss portion 30. The lubricating oil passage 30b communicates with the oil passage 25a, and the oil flowing through the oil passage 25a is introduced from the lubricating oil passage 30b into an oil passage, not shown, formed in the engine body 7. The oil introduced from the lubricating oil passage 30b into the oil passage of the engine body 7 is supplied to the lubricating portion of the engine body 7.

The boss portion 30 is provided with

outlet oil passages

30c, 30d, and the

outlet oil passages

30c, 30d are provided between the through hole 30a and the lubricating oil passage 30b in the vertical direction. The outlet oil passage 30c communicates with the cylinder section 27, and the oil supplied from the oil passage 25a to the cylinder section 27 through the oil passage 19g is supplied from the outlet oil passage 30c to the advance chamber of the exhaust side variable valve mechanism 53.

The outlet oil passage 30d communicates with the cylinder section 27, and the oil supplied from the oil passage 25a to the cylinder section 27 through the oil passage 19g is supplied from the outlet oil passage 30d to the retard chamber of the exhaust side variable valve mechanism 53.

When the spool 28A is driven by the control portion 28B, the hydraulic control valve 28 supplies the oil supplied to the cylinder portion 27 through the

oil passages

24a, 25a to the advance chamber or the retard chamber of the exhaust variable valve mechanism 53 through the outlet oil passage 30c or the outlet oil passage 30 d. That is, the hydraulic control valve 28 switches the supply path of the oil between a path flowing from the cylinder section 27 to the advance chamber and a path flowing from the cylinder section 27 to the retard chamber.

In fig. 7, the connecting wall 19 is provided with

drain oil passages

35a and 35b, and the

drain oil passages

35a and 35b return oil returned from the advance chamber or the retard chamber of the exhaust variable valve mechanism 53 to the cylinder section 27 from the cylinder section 27 to a space 54 (see fig. 10) between the chain cover 18 and the engine main body 7. The oil returned to the space 54 is stored to the oil pan 14.

The

discharge oil passages

35A, 35B are formed in

cylindrical portions

35A, 35B provided in the connecting wall 19. In fig. 10, the tube portion 35A is a portion formed in a tubular shape by the cylinder portion 27 and the connecting wall 19, and although not shown, the tube portion 35B is also formed in a tubular shape by the cylinder portion 27 and the connecting wall 19. The

tubular portions

35A and 35B of the present embodiment constitute the 3 rd tubular portion of the present invention.

As shown in fig. 7, the

cylindrical portions

35A, 35B are connected to the oil passage portion 25 on the side opposite to the boss portion 30. That is, the boss portion 30 is provided above the oil passage portion 25, and the

tube portions

35A and 35B are provided below the oil passage portion 25. Thus, the oil passage portion 25 is sandwiched between the boss portion 30 and the

tubular portions

35A, 35B in the vertical direction.

In fig. 11, a plate-shaped rib 19E is provided on the connecting wall 19, and the rib 19E has the same thickness as the diameter (the diameter in the vertical direction) of the oil passage portion 25. The cylinder section 27 is linked to the 2 nd oil passage section 25 by a rib 19E.

In fig. 9, a sensor boss portion 31 is provided on the chain cover 18. The sensor 32 is fitted to the sensor boss portion 31, and the sensor boss portion 31 supports the sensor 32. The sensor 32 detects a state of the oil flowing in the

oil passages

24a, 25a, such as an oil temperature of the oil, an oil pressure, or an oil temperature and a pressure of the oil.

As described above, according to the cover structure of the engine 5 of the present embodiment, the chain cover 18 has the cylinder portion 27, and the cylinder portion 27 is bulged from the connecting wall 19 to the side opposite to the engine main body 7, and is provided on the lower side of the attachment fitting portion 22, into which the spool valve 28A is inserted.

The chain cover 18 further includes: an oil passage portion 24 that bulges out from the connecting wall 19 toward the engine body 7 and extends in the vertical direction of the chain cover 18; and an oil passage portion 25 that bulges out from the connecting wall 19 toward the engine body 7 and is connected to the upper ends of the

side walls

19A, 19B and the oil passage portion 24.

The oil passage 24a is formed inside the oil passage portion 24, and the oil passage 25a is formed inside the oil passage portion 25.

This can increase the rigidity of the connecting wall 19 around the oil passage portion 25 including the oil passage portion 25 by the oil passage portion 25, and suppress vibration of the connecting wall 19 around the oil passage portion 25 including the oil passage portion 25.

The cylinder portion 27 has a wall portion 27A connected to the wall portion 25A of the oil passage portion 25, and the cylinder portion 27 extends along the oil passage portion 25.

Thus, by connecting the cylinder section 27 to the highly rigid oil passage section 25, the rigidity of the cylinder section 27 can be increased, and vibration of the cylinder section 27 can be suppressed. As a result, vibration of the hydraulic control valve 28 attached to the chain cover 18 can be reduced, and the reliability of the hydraulic control valve 28 can be improved.

In addition, according to the cover structure of the present embodiment, the chain cover 18 has the boss portion 30 having one end joined to the cylinder portion 27 and the other end joined to the engine main body 7. The boss portion 30 has

outlet oil passages

30c, 30d that supply oil from the hydraulic control valve 28 to the exhaust side variable valve mechanism 53, and is connected to the oil passage portion 25.

Thus, the rigidity of the cylinder portion 27 can be further improved by connecting the cylinder portion 27 to the oil passage portion 25 and the boss portion 30, respectively, which have high rigidity. Therefore, the vibration of the cylinder portion 27 can be suppressed more effectively. As a result, the vibration of the hydraulic control valve 28 attached to the chain cover 18 can be reduced more effectively, and the reliability of the hydraulic control valve 28 can be further improved.

Further, according to the cover structure of the present embodiment, the connecting wall 19 is provided with the

cylinder portions

35A, 35B, and the

cylinder portions

35A, 35B have the

discharge oil passages

35A, 35B that discharge oil from the cylinder portion 27 to the space 54 between the chain cover 18 and the engine main body 7.

The

cylindrical portions

35A and 35B are connected to the oil passage portion 25 on the side opposite to the boss portion 30.

This allows the oil passage portion 25 to be connected to the highly rigid

cylindrical portions

35A and 35B, and the rigidity of the oil passage portion 25 can be further improved. Further, since the cylinder section 27 can be connected to the oil passage section 25 having a further higher rigidity, the rigidity of the cylinder section 27 can be further improved.

Therefore, the vibration of the cylinder portion 27 can be suppressed more effectively. As a result, the vibration of the hydraulic control valve 28 attached to the chain cover 18 can be reduced more effectively, and the reliability of the hydraulic control valve 28 can be further improved.

In addition, according to the cover structure of the present embodiment, the cylinder portion 27 is linked to the oil passage portion 25 by the plate-shaped rib 19E having the same thickness as the diameter of the oil passage portion 25.

Thus, the rib 19E having high rigidity is connected to the oil passage portion 25, whereby the rigidity of the oil passage portion 25 can be further improved. Further, since the cylinder section 27 can be connected to the oil passage section 25 having a further higher rigidity, the rigidity of the cylinder section 27 can be further improved.

The cover member of the present embodiment is constituted by the chain cover 18, but the cover member covering the end of the engine main body 7 is not limited to the chain cover 18.

Although embodiments of the present invention have been disclosed, it will be apparent to those skilled in the art that modifications can be made without departing from the scope of the invention. All such modifications and equivalents are intended to be included in the claims.

Claims

1. A cover structure for an internal combustion engine, comprising: an engine main body having a crankshaft, a camshaft, and a variable valve mechanism that changes a relative rotational phase of the camshaft with respect to the crankshaft; a cover member having a pair of side walls fixed to end portions of the engine main body, a connecting wall provided between the pair of side walls and covering the end portions of the engine main body and connecting the pair of side walls, and a mounting fitting portion provided on an upper portion of the connecting wall and adapted to fit a mounting member provided on a vehicle body side; and a hydraulic control valve having a valve portion for supplying oil for operating the variable valve mechanism, wherein the cover structure of the internal combustion engine,

the cover member includes: a cylinder portion that bulges from the connecting wall to a side opposite to the engine body, is provided below the mount mounting portion, and is inserted into the valve portion; a 1 st cylinder portion that bulges out from the connecting wall toward the engine main body and extends in the vertical direction of the cover member; a 2 nd cylindrical portion that bulges out from the connecting wall toward the engine main body and is connected to the pair of side walls and an upper end of the 1 st cylindrical portion; and an inlet oil passage for supplying oil to the hydraulic cylinder section,

the inlet oil passage includes: a 1 st oil passage formed inside the 1 st cylinder part; and a 2 nd oil passage formed inside the 2 nd cylinder portion and communicating with the 1 st oil passage and the cylinder portion,

the cylinder portion has a wall portion connected to a wall portion of the 2 nd cylindrical portion, and extends along the 2 nd cylindrical portion.

2. The cover structure of an internal combustion engine according to claim 1,

the cover member has a boss portion having one end connected to the cylinder portion and the other end connected to the engine main body,

the boss portion has an outlet oil passage for supplying oil from the hydraulic control valve to the variable valve mechanism, and is connected to the 2 nd cylindrical portion.

3. The cover structure of the internal combustion engine according to claim 2,

a 3 rd cylindrical portion having a drain oil passage for draining oil from the cylinder portion to a space between the cover member and the engine main body is provided in the connecting wall,

the 3 rd cylindrical portion is coupled to the 2 nd cylindrical portion on a side opposite to the boss portion.

4. The cover structure of the internal combustion engine according to any one of claims 1 to 3,

the cylinder portion is connected to the 2 nd cylindrical portion by a plate-shaped rib having the same thickness as the diameter of the 2 nd cylindrical portion.