JP7524817B2 - Cover structure for internal combustion engine - Google Patents

Description

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

A solenoid valve is known that supplies control oil to a valve timing control device that adjusts the relative rotational phase of a camshaft with respect to a crankshaft (see Patent Document 1).

This solenoid valve has a spool valve body that supplies and discharges oil to the valve timing control device, and the spool valve body is operated by a solenoid.

The spool valve body is located in the center of the valve timing control device so that it rotates integrally with the camshaft, and the solenoid is fixed to the chain cover so that it faces the spool valve body in the central axial direction of the valve timing control device.

JP 2018-3694 A

However, in the solenoid valve described in Patent Document 1, a drain hole is provided at the axial end of the spool valve body to drain oil from the spool valve body.

The spool valve body rotates together with the camshaft, so the oil discharged from the drain hole is scattered inside the cover member as it rotates due to centrifugal force. This makes it difficult to quickly return the oil to the oil pan.

The present invention was made in response to the above-mentioned problems, and aims to provide a cover structure for an internal combustion engine that can quickly return oil discharged from a spool valve that rotates integrally with the camshaft to the oil pan.

The present invention provides a valve timing adjustment device that is fixed to an end of a camshaft that is rotatably provided on an engine body, and to which the power of the crankshaft is transmitted via a transmission member; a cover member that is fixed to the end of the engine body so as to cover the transmission member and the valve timing adjustment device; and a hydraulic control valve that operates the valve timing adjustment device with oil and adjusts the relative rotation phase of the camshaft with respect to the crankshaft, the hydraulic control valve being installed on the central axis of rotation of the valve timing adjustment device so as to rotate integrally with the camshaft, a spool valve that supplies oil to the valve timing adjustment device, and a hydraulic control valve that faces the spool valve in the direction of the central axis of rotation of the valve timing adjustment device. A cover structure for an internal combustion engine has a solenoid that operates the spool valve and is attached to the cover member, the spool valve has a discharge part that discharges oil from the spool valve into the inside of the cover member, and the discharge part is provided at the end of the solenoid side in the direction of the central axis of the rotation of the valve timing adjustment device, the cover member has an oil receiving part installed below the solenoid to capture the oil discharged from the drain hole, the oil receiving part protrudes from the inner wall surface of the cover member that faces the engine body in the direction of the central axis of the rotation of the valve timing adjustment device toward the discharge part, and extends in an arc along the outer periphery of the solenoid.

In this way, according to the present invention, the oil discharged from the spool valve that rotates integrally with the camshaft can be quickly returned to the oil pan.

FIG. 1 is a front view of an internal combustion engine according to an embodiment of the present invention. FIG. 2 is a diagram showing the internal structure of a chain cover for an internal combustion engine according to one embodiment of the present invention. FIG. 3 is a top view of the internal combustion engine according to one embodiment of the present invention, showing a state in which the cylinder head cover has been removed. 4 is a cross-sectional view taken along the line IV-IV in FIG. FIG. 5 is an upper inside side view of a chain cover for an internal combustion engine according to one embodiment of the present invention. FIG. 6 is a top perspective view of a chain cover for an internal combustion engine according to one embodiment of the present invention.

An internal combustion engine according to one embodiment of the present invention includes a valve timing adjustment device fixed to an end of a camshaft rotatably provided on an engine body, to which the power of the crankshaft is transmitted via a transmission member, a cover member fixed to the end of the engine body so as to cover the transmission member and the valve timing adjustment device, and a hydraulic control valve that operates the valve timing adjustment device with oil and adjusts the relative rotation phase of the camshaft with respect to the crankshaft, the hydraulic control valve being installed on the rotation center axis of the valve timing adjustment device so as to rotate integrally with the camshaft, a spool valve that supplies oil to the valve timing adjustment device, and a cover member fixed to the end of the engine body so as to cover the transmission member and the valve timing adjustment device. A cover structure for an internal combustion engine has a solenoid that operates the spool valve and is attached to the cover member so as to face the spool valve in the axial direction, the spool valve has a discharge part that discharges oil from the spool valve into the inside of the cover member, and the discharge part is provided at the end on the solenoid side in the direction of the central axis of the rotation of the valve timing adjustment device, and the cover member has an oil receiving part installed below the solenoid to capture oil discharged from the drain hole, and the oil receiving part protrudes from the inner wall surface of the cover member that faces the engine body in the direction of the central axis of the rotation of the valve timing adjustment device toward the discharge part side and extends in an arc along the outer periphery of the solenoid.

As a result, the cover structure for an internal combustion engine according to one embodiment of the present invention can quickly return oil discharged from the spool valve, which rotates integrally with the camshaft, to the oil pan.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a cover structure for an internal combustion engine according to the present invention will be described with reference to the drawings.
1 to 6 are diagrams showing a cover structure for an internal combustion engine according to one embodiment of the present invention. In Fig. 1 to Fig. 6, the up, down, front, rear, left and right directions are defined as follows.

The direction along the crankshaft is the front-to-rear direction of the engine, with the side where the timing chain is located being the front and the opposite side being the rear. The direction along the central axis of the cylinder is the up-down direction of the engine, with the cylinder head side being the top and the opposite side being the bottom. The direction that intersects with the crankshaft and the central axis of the cylinder is the left-to-right direction of the engine, with the left side of the cylinder central axis when looking at the crankshaft from the rear being the left and the right side of the cylinder central axis being the right.

First, the configuration will be described.
1, an engine 1 includes an engine body 2. The engine body 2 includes a cylinder block 3, a cylinder head 4, a cylinder head cover 5, and an oil pan 6. The engine 1 of this embodiment constitutes an internal combustion engine.

The cylinder block 3 has multiple cylinders (not shown), which are arranged in a line in the front-to-rear direction of the engine 1.

Each cylinder contains a piston (not shown), which is connected to the crankshaft 7 via a connecting rod (not shown). The piston reciprocates within the cylinder, causing the crankshaft 7 to rotate via the connecting rod. The cylinder head 4 is formed with a number of intake ports and a number of exhaust ports (not shown).

The intake ports are connected to the cylinders and introduce intake air into the cylinders. The exhaust manifold is connected to multiple cylinders through exhaust ports, and collects exhaust gases discharged from the multiple cylinders and discharges them from the exhaust port to a catalytic converter (not shown).

As shown in FIG. 3, the intake camshaft 11 and the exhaust camshaft 12 are rotatably supported in the cylinder head 4. The intake camshaft 11 and the exhaust camshaft 12 are installed side by side in the left-right direction of the engine 1 with their rotational center axes 11a and 12a extending parallel to the front-rear direction of the engine 1.

The intake camshaft 11 has multiple intake cams 11A (two shown), which are arranged side by side in the direction of the rotational center axis 11a of the intake camshaft 11.

For example, two intake cams 11A are provided for each cylinder. An intake valve (not shown) is provided in the intake port, and the intake cam 11A operates the intake valve to open and close the intake port, thereby connecting or blocking the cylinder and the intake port.

The exhaust camshaft 12 is equipped with multiple exhaust cams 12A (two in the figure), and the exhaust cams 12A are arranged side by side in the direction of the rotation center axis 12a of the exhaust camshaft 12. Hereinafter, the direction of the rotation center axes 11a, 12a will be referred to as the rotation center axis direction.

For example, two exhaust cams 12A are provided for each cylinder. An exhaust valve (not shown) is provided in the exhaust port, and the exhaust cam 12A operates the exhaust valve to open and close the exhaust port, connecting or blocking the cylinder and the exhaust port.

The intake valve timing adjustment device 15 is attached to the front end (end) of the intake camshaft 11 in the direction of the central axis of rotation. The intake valve timing adjustment device 15 has an intake housing member 23, and an intake sprocket 23S is provided on the outer periphery of the intake housing member 23.

An exhaust valve timing adjustment device 16 is attached to the front end (end) of the exhaust camshaft 12 in the direction of the central axis of rotation. The exhaust valve timing adjustment device 16 has an exhaust housing member 24, and an exhaust sprocket 24S is provided on the outer periphery of the exhaust housing member 24.

The length of the intake side housing member 23 in the direction of the central axis of rotation of the intake camshaft 11 and the exhaust camshaft 12 is longer than the length of the exhaust side housing member 24.

As shown in Figures 1 and 2, a crank sprocket 7S is provided at the front end of the crankshaft 7. A timing chain 8 is wound around the crank sprocket 7S, the intake sprocket 23S, and the exhaust sprocket 24S. In this embodiment, the timing chain 8 constitutes a transmission member.

The power of the crankshaft 7 is transmitted to the intake camshaft 11 and the exhaust camshaft 12 via the timing chain 8. As a result, the intake camshaft 11 rotates and the intake cam 11A opens and closes the intake valve, and the exhaust camshaft 12 rotates and the exhaust cam 12A opens and closes the exhaust valve.

The intake valve timing adjustment device 15 adjusts the relative rotational phase of the intake camshaft 11 with respect to the crankshaft 7, and adjusts the opening and closing timing (valve timing) of the intake valves.

The exhaust valve timing adjustment device 16 adjusts the relative rotational phase of the exhaust camshaft 12 with respect to the crankshaft 7 to adjust the opening and closing timing (valve timing) of the exhaust valve. In this embodiment, the intake camshaft 11 constitutes a camshaft, and the intake valve timing adjustment device 15 constitutes a valve timing control device.

As shown in Figures 1 and 2, the cylinder block 3 is provided with an oil pump 35. The oil pump 35 is driven by the crankshaft 7 to supply oil stored in the oil pan 6 to each part of the engine 1.

A chain cover 20 is attached to the front end (end) of the cylinder block 3 and the front end (end) of the cylinder head 4.

The chain cover 20 is formed so that the vertical direction of the chain cover 20 is longer than the horizontal direction of the chain cover 20, so that the longitudinal direction is along the vertical direction of the engine 1 and the transverse direction is along the horizontal direction of the engine 1. As shown in Figures 1 to 3, the chain cover 20 has a vertical wall 20A, a left side wall 20B, and a right side wall 20C.

The vertical wall 20A faces the front ends of the cylinder block 3 and the cylinder head 4 in the direction of the central rotation axis of the intake camshaft 11 and the exhaust camshaft 12.

The left side wall 20B and the right side wall 20C protrude from the right and left ends of the chain cover 20 in the short direction (left-right direction of the chain cover 20) toward the engine body 2, and their protruding tips are fastened to the front end of the cylinder block 3 and the front end of the cylinder head 4 by multiple bolts 33A (see Figure 1). In this way, the chain cover 20 is fixed to the engine body 2.

As shown in Figures 3 and 4, the chain cover 20 houses the timing chain 8, the intake valve timing adjustment device 15, and the exhaust valve timing adjustment device 16. In Figures 3 and 4, the timing chain 8 is shown by phantom lines.

That is, the timing chain 8, the intake valve timing adjustment device 15, and the exhaust valve timing adjustment device 16 are installed in a space 30 surrounded by the cylinder block 3, the cylinder head 4, and the chain cover 20. In this embodiment, the chain cover 20 constitutes a cover member.

The power of the crankshaft 7 is transmitted to the intake side housing member 23 of the intake side valve timing adjustment device 15 via the timing chain 8.

As shown in FIG. 4, the intake side housing member 23 houses the intake side vane rotor 23B, which rotates integrally with the intake camshaft 11. The intake side vane rotor 23B divides the inside of the intake side housing member 23 into multiple advance chambers and multiple retard chambers (not shown).

The intake side valve timing adjustment device 15 is provided with an intake side spool valve 25. The intake side spool valve 25 is installed on the rotation center axis 15a of the intake side valve timing adjustment device 15 so as to rotate integrally with the intake camshaft 11, and is freely movable in the direction of the rotation center axis 15a of the intake side valve timing adjustment device 15 (hereinafter referred to as the rotation center axis direction).

Specifically, the intake side spool valve 25 is installed inside the intake side housing member 23. A hole 11b is provided at the front end of the intake camshaft 11, and the intake side spool valve 25 is accommodated in the hole 11b and the intake side housing member 23 so that it can move freely in the direction of the central axis of rotation of the intake side valve timing adjustment device 15.

An intake side solenoid 31 is provided on the chain cover 20, and the intake side solenoid 31 is attached to the chain cover 20 so as to face the intake side spool valve 25 in the direction of the central axis of rotation of the intake side valve timing adjustment device 15.

The intake side solenoid 31 operates the intake side spool valve 25 so that the intake side spool valve 25 moves in the direction of the central axis of rotation of the intake side valve timing adjustment device 15.

When the intake solenoid 31 moves to the advance chamber position in the direction of the central axis of rotation of the intake valve timing adjustment device 15, oil is supplied from the oil pump 35 to the advance chamber.

When oil is supplied to the advance chamber, the intake vane rotor 23B rotates relative to the intake housing member 23, adjusting the relative rotation phase of the intake camshaft 11 to the crankshaft 7 to the advance side, and adjusting the opening and closing timing of the intake valve to the advance side.

When the intake solenoid 31 moves to the retard position in the direction of the central axis of rotation of the intake valve timing adjustment device 15, oil is supplied from the oil pump 35 to the retard chamber.

When oil is supplied to the retard chamber, the intake vane rotor 23B rotates relative to the intake housing member 23, adjusting the relative rotational phase of the intake camshaft 11 to the crankshaft 7 to a retarded angle, and adjusting the opening and closing timing of the exhaust valve to the retarded side.

In this way, the intake side spool valve 25 and the intake side solenoid 31 of this embodiment operate the intake side valve timing adjustment device 15 with oil, and adjust the relative rotation phase of the intake camshaft 11 with respect to the crankshaft 7. The intake side spool valve 25 and the intake side solenoid 31 of this embodiment constitute a hydraulic control valve.

As shown in Figures 3 and 4, the intake spool valve 25 has a drain hole 25a. The drain hole 25a is provided at the front end 25f on the intake solenoid 31 side in the direction of the central axis of rotation of the intake valve timing adjustment device 15.

When oil is supplied to the advance chamber, the drain hole 25a drains the oil in the retard chamber from the intake spool valve 25 to the inside of the chain cover 20, and when oil is supplied to the retard chamber, the drain hole 25 drains the oil in the advance chamber from the intake spool valve 25 to the inside of the chain cover 20. In this embodiment, the drain hole 25a constitutes the discharge section.

As shown in FIG. 3, the power of the crankshaft 7 is transmitted to the exhaust side housing member 24 of the exhaust side valve timing adjustment device 16 via a timing chain 8.

The exhaust side housing member 24 houses an exhaust side vane rotor (not shown), which rotates integrally with the exhaust camshaft 12. The exhaust side vane rotor divides the interior of the exhaust side housing member 24 into multiple advance chambers and multiple retard chambers (not shown).

As shown in FIG. 3, the exhaust valve timing adjustment device 16 is provided with an exhaust spool valve 26. The exhaust spool valve 26 is installed on the central axis of the exhaust valve timing adjustment device 16 so as to rotate integrally with the exhaust camshaft 12, and is freely movable in the direction of the central axis of rotation.

The exhaust spool valve 26 is operated by the exhaust solenoid 32, and similar to the intake valve timing adjustment device 15, by supplying oil to either the advance or retard chamber, thereby adjusting the relative rotational phase of the exhaust camshaft 12 to the crankshaft 7 to the advance or retard side, and adjusting the opening and closing timing of the exhaust valve to the advance or retard side.

The exhaust spool valve 26 is provided with a drain hole (not shown). The drain hole is provided at the front end (end) on the exhaust solenoid 32 side in the direction of the central axis of rotation of the exhaust valve timing adjustment device 16.

When oil is supplied to the advance chamber, the drain hole drains the oil in the retard chamber from the exhaust spool valve 26 to the inside of the chain cover 20, and when oil is supplied to the retard chamber, the drain hole drains the oil in the advance chamber from the exhaust spool valve 26 to the inside of the chain cover 20.

As shown in Figures 5 and 6, the vertical wall 20A of the chain cover 20 has an intake side through hole 20a and an exhaust side through hole 20b.

The intake side solenoid 31 is inserted into the intake side through hole 20a, and the intake side solenoid 31 is fixed to the vertical wall 20A of the chain cover 20 by a bolt (not shown).

The exhaust side solenoid 32 is inserted into the exhaust side through hole 20b, and the exhaust side solenoid 32 is fixed to the vertical wall 20A of the chain cover 20 by a bolt (not shown).

As shown in Figures 5 and 6, the chain cover 20 is provided with ribs 20c, 20d, and 20e. Rib 20c is provided below the intake solenoid 31. Rib 20c extends in an arc along the outer periphery of the intake solenoid 31, with the center of rib 20c in the left-right direction being located at the lowest point.

As shown in Figures 3 and 4, the rib 20c protrudes from the inner wall surface 20f of the vertical wall 20A of the chain cover 20, which faces the engine body 2 in the direction of the central axis of rotation of the intake side valve timing adjustment device 15, toward the drain hole 25a of the intake side spool valve 25.

The tip 20p of the rib 20c in the protruding direction protrudes from the inner wall surface 20f of the vertical wall 20A toward the drain hole 25a beyond the rear end (end) 31a of the intake solenoid 31 in the direction of the central axis of rotation of the intake valve timing adjustment device 15.

As shown in Figures 5 and 6, the rib 20d is provided below the exhaust side through hole 20b, i.e., below the exhaust side solenoid 32, and extends in an arc along the outer periphery of the exhaust side through hole 20b (exhaust side solenoid 32). The center of the rib 20d in the left-right direction is located at the lowest point.

The rib 20d protrudes from the inner wall surface 20f of the vertical wall 20A of the chain cover 20, which faces the engine body 2 in the direction of the rotation axis of the exhaust valve timing adjustment device 16, toward the drain hole side of the exhaust spool valve 26.

Rib 20e is provided below rib 20c. As shown in FIG. 4, rib 20e protrudes from the inner wall surface 20f of the vertical wall 20A of the chain cover 20 toward the drain hole 25a beyond rib 20c.

As shown in Figures 1 and 2, the timing chain 8 has a slack side 8a to which tension is applied by a chain tensioner (not shown), and the slack side 8a is installed between the crank sprocket 7S and the intake sprocket 23S.

As shown in FIG. 2, the rib 20e curves downward from the left end 20i to the right end 20k, and the right end 20k is positioned so that it does not overlap with the slack side 8a of the timing chain 8 in the vertical direction (the longitudinal direction of the chain cover 20). In this embodiment, the rib 20c constitutes a rib and a first oil receiving portion, and the rib 20e constitutes a second oil receiving portion.

As shown in Figures 2, 5, and 6, the chain cover 20 is provided with a vertical rib 20g. The vertical rib 20g is provided on the opposite side of the right side wall 20C with respect to the intake side through hole 20a in the short direction of the chain cover 20.

The vertical rib 20g is located at the center of the short side of the chain cover 20 (the center of the left-right direction of the chain cover 20) and extends in the vertical direction, protruding from the inner wall surface 20f of the chain cover 20 toward the engine body 2.

Specifically, the vertical rib 20g extends from directly above the oil pump 35 to between the intake side through hole 20a and the exhaust side through hole 20b in the center of the short side of the vertical wall 20A.

As shown in Figures 5 and 6, the left ends 20h and 20i of the ribs 20c and 20e are connected to the vertical rib 20g, and the right ends 20j and 20k of the ribs 20c and 20e are connected to the right side wall 20C.

That is, both short sides of the ribs 20c and 20e are connected to the vertical rib 20g and the right side wall 20C. In this embodiment, the intake side through hole 20a constitutes a through hole, and the right side wall 20C constitutes the side wall of the cover member.

Next, the effect of the cover structure of the engine 1 according to this embodiment will be described.
The cover structure for the engine 1 in this embodiment includes an intake side valve timing controller 15 which is fixed to the front end of the intake camshaft 11 which is rotatably mounted on the cylinder head 4 and to which the power of the crankshaft 7 is transmitted via a timing chain 8, and a chain cover 20 which is fixed to the front ends of the cylinder block 3 and the cylinder head 4 so as to cover the timing chain 8, the intake side valve timing controller 15, and the exhaust side valve timing controller 16.

The engine 1 also has a hydraulic control valve that uses oil to operate the intake valve timing adjustment device 15 and adjust the relative rotational phase of the intake camshaft 11 with respect to the crankshaft 7.

The hydraulic control valve is installed on the central axis of the intake side valve timing adjustment device 15 so as to rotate integrally with the intake camshaft 11, and has an intake side spool valve 25 that supplies oil to the intake side valve timing adjustment device 15, and an intake side solenoid 31 that is attached to the chain cover 20 so as to face the intake side spool valve 25 in the direction of the central axis of the intake side valve timing adjustment device 15 and operates the intake side spool valve 25.

The intake side spool valve 25 has a drain hole 25a that drains oil from the intake side spool valve 25 to the inside of the chain cover 20, and the drain hole 25a is provided at the front end 25f on the intake side solenoid 31 side in the direction of the central axis of rotation of the intake side valve timing adjustment device 15.

When the intake camshaft 11 rotates in the clockwise direction W in Figure 6, the intake camshaft 11 rotates together with the intake spool valve 25, and the oil discharged from the drain hole 25a is scattered radially by centrifugal force while rotating around the central axis of rotation of the intake valve timing adjustment device 15.

According to the cover structure of the engine 1 of this embodiment, the chain cover 20 is installed below the intake solenoid 31 and has a rib 20c that captures the oil discharged from the intake spool valve 25.

The rib 20c protrudes from the inner wall surface 20f of the chain cover 20, which faces the engine body 2 in the direction of the central axis of rotation of the intake side valve timing adjustment device 15, toward the drain hole 25a, and extends in an arc along the outer periphery of the intake side solenoid 31.

As a result, oil O1 (see FIG. 6) splashing from the drain hole 25a is captured by the rib 20c, and the captured oil O1 is collected in the left-right center of the lowest of the ribs 20c (see O2 in FIG. 6), and then allowed to drop downward from the left-right center of the rib 20c and return to the oil pan 6.

As a result, the oil discharged from the intake side spool valve 25, which rotates integrally with the intake camshaft 11, can be quickly returned to the oil pan 6.

In addition, in the exhaust valve timing adjustment device 16, the oil scattering from the drain hole of the exhaust spool valve 26 is captured by the rib 20d, and the captured oil is collected in the left-right center of the lowest of the ribs 20d, and then allowed to drop downward from the left-right center of the rib 20d and return to the oil pan 6.

As a result, the oil discharged from the exhaust spool valve 26, which rotates integrally with the exhaust camshaft 12, can be quickly returned to the oil pan 6.

In addition, according to the cover structure of the engine 1 of this embodiment, the tip 20p of the rib 20c in the protruding direction protrudes toward the drain hole 25a beyond the rear end 31a of the intake solenoid 31 in the direction of the central axis of rotation of the intake valve timing adjustment device 15.

This allows the rib 20c to more easily capture and collect oil that splashes out from the drain hole 25a. This allows the oil discharged from the intake spool valve 25, which rotates integrally with the intake camshaft 11, to be returned to the oil pan 6 more quickly.

In addition, according to the cover structure of the engine 1 of this embodiment, the chain cover 20 has a rib 20e below the rib 20c. The rib 20e protrudes from the inner wall surface 20f of the chain cover 20 toward the drain hole 25a beyond the rib 20c.

This allows oil O2 falling from rib 20c to be captured by rib 20e as shown by oil O3 in Figure 6.

The rib 20e curves downward from the left end 20i to the right end 20k, and the right end 20k is positioned so that it does not overlap with the slack side 8a of the timing chain 8 in the vertical direction.

In other words, the rib 20e guides the oil O3 captured by the rib 20e to a position that does not overlap with the slack side 8a of the timing chain 8 in the vertical direction of the engine 1 and allows it to fall from the rib 20e, thereby preventing the oil O3 from colliding with the timing chain 8 even if the timing chain 8 vibrates (see Figure 2).

This allows the oil discharged from the intake spool valve 25, which rotates integrally with the intake camshaft 11, to be returned to the oil pan 6 more quickly.

In addition, according to the engine 1 of this embodiment, the chain cover 20 has a vertical wall 20A that faces the front end of the engine body 2 in the direction of the central axis of rotation of the intake side valve timing adjustment device 15, and a right side wall 20C that protrudes from the right end of the short side of the chain cover 20 toward the engine body 2 and has a tip end in the protruding direction that is fastened to the engine body 2.

The chain cover 20 also has an intake side through hole 20a formed in the vertical wall 20A, into which the intake side solenoid 31 is inserted, and a vertical rib 20g that is provided on the opposite side of the right side wall 20C from the intake side through hole 20a in the short direction of the chain cover 20 and that protrudes from the inner wall surface 20f of the chain cover 20 toward the engine body 2 and extends in the vertical direction.

In addition, both sides of ribs 20c and 20e are connected to right side wall 20C and vertical rib 20g.

As a result, the vertical gaps on both sides of the ribs 20c and 20e in the left-right direction can be blocked by the right side wall 20C of the chain cover 20 and the vertical rib 20g. This prevents oil splashing from the drain hole 25a from leaking out of the gap, and allows the oil to be collected and returned to the oil pan 6 more quickly.

In addition, in the cover structure of the engine 1 in this embodiment, the first oil receiving portion and the second oil receiving portion are composed of the intake side ribs 20c and 20e, but the first oil receiving portion may be composed of the rib 20d, and the rib 20e may be provided below the rib 20d to serve as the second oil receiving portion.

Although an embodiment of the present invention has been disclosed, it is apparent that modifications may be made by one of ordinary skill in the art without departing from the scope of the present invention. All such modifications and equivalents are intended to be encompassed by the following claims.

1...Engine (internal combustion engine), 2...Engine body, 7...Crankshaft, 8...Timing chain (transmission member), 15...Intake side valve timing adjustment device (valve timing adjustment device), 15a...Rotation center axis (rotation center axis of valve timing adjustment device), 20...Chain cover (cover member), 20A...Vertical wall, 20a...Intake side through hole (through hole), 20C...Right side wall (side wall of cover member), 20c...Rib (oil receiving part, first oil receiving part), 20e...Rib (second oil receiving part), 20f...Inner wall surface (inner wall surface of cover member), 20g...Vertical rib, 20p...Tip (tip in the protruding direction of the oil receiving part), 25...Intake side spool valve (hydraulic control valve), 25a...Drain hole (discharge part), 25f...Front end (end on the solenoid side in the direction of the rotation center axis of the valve timing adjustment device), 31...Intake side solenoid (hydraulic control valve)

Claims (4)

a valve timing adjusting device fixed to an end of a camshaft rotatably provided on an engine body, to which power of a crankshaft is transmitted via a transmission member;
a cover member fixed to an end portion of the engine body so as to cover the transmission member and the valve timing adjusting device;
a hydraulic control valve that operates the valve timing adjusting device with oil and adjusts the relative rotation phase of the camshaft with respect to the crankshaft,
the hydraulic control valve is provided on a rotational axis of the valve timing adjusting device so as to rotate integrally with the camshaft, and includes a spool valve that supplies oil to the valve timing adjusting device, and a solenoid that is attached to the cover member so as to face the spool valve in the direction of the rotational axis of the valve timing adjusting device, and operates the spool valve,
the spool valve has a discharge portion that discharges oil from the spool valve to an inside of the cover member,
a cover structure for an internal combustion engine, the exhaust portion being provided at an end portion of the valve timing control device on the solenoid side in a direction of a rotation central axis,
the cover member has an oil receiving portion disposed below the solenoid so as to capture the oil discharged from the discharge portion,
a valve timing adjusting device that adjusts the oil pressure in the valve timing adjusting device to a pressure required for the valve timing adjusting device to be in a pressure range from 0.5 to 1.0 MPa, and the valve timing adjusting device is configured to adjust ... The cover structure for an internal combustion engine according to claim 1, characterized in that the tip of the oil receiving portion in the protruding direction protrudes toward the discharge portion further than the end of the solenoid in the direction of the central axis of rotation of the valve timing adjustment device. When the oil receiving portion is a first oil receiving portion,
the cover member has a second oil receiving portion below the first oil receiving portion,
the second oil receiving portion protrudes from an inner wall surface of the cover member toward the discharge portion further than the first oil receiving portion,
3. The cover structure for an internal combustion engine according to claim 1, wherein the second oil receiving portion captures oil falling from the first oil receiving portion, guides the oil to a position in the vertical direction where it does not overlap with the transmission member, and allows the oil to fall from the second oil receiving portion. The cover member is
a vertical wall that faces an end of the engine body and an end of the valve timing adjusting device in a direction of a rotational axis of the valve timing adjusting device;
a side wall that protrudes from a short-side end of the cover member toward the engine body and has a tip end in the protruding direction that is fastened to the engine body; a through hole that is formed in the vertical wall and into which the solenoid is inserted;
a vertical rib provided on the opposite side of the side wall with respect to the through hole in the short direction of the cover member, the vertical rib protruding from the inner wall surface of the cover member toward the engine body and extending in the up-down direction,
4. The cover structure for an internal combustion engine according to claim 3, wherein both short side portions of the cover member of the first oil receiving portion and the second oil receiving portion are connected to the side wall and the vertical rib.

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