JP7740097B2 - Cam angle sensor mounting structure for internal combustion engine - Google Patents

Description

The present invention relates to a mounting structure for a cam angle sensor in an internal combustion engine.

In vehicle engines, cam angle sensors are known that detect the rotational positions (rotation angles) of the intake camshaft and exhaust camshaft.

A conventional engine cam angle sensor mounting structure is known in which the cam angle sensor (TDC sensor) is attached to the cylinder head cover that covers the top of the cylinder head.

With this cam angle sensor mounting structure, the cam angle sensor is attached to the front and rear top surfaces of the cylinder head cover from the outside with bolts so as not to interfere with the downward-sloping hood.

Japanese Patent Application Publication No. 10-37835

However, in conventional cam angle sensor mounting structures, the cam angle sensor is mounted on a flat portion of the cylinder head cover.

The flat portion of this cylinder head cover has a large surface area and low surface rigidity, which means that the cam angle sensor is prone to vibrating due to engine vibrations, which could reduce the detection accuracy of the intake camshaft and exhaust camshaft.

The present invention was made in light of the above-mentioned circumstances, and aims to provide a mounting structure for a cam angle sensor in an internal combustion engine that improves the rigidity around the mounting location of the cam angle sensor, suppresses vibration of the cam angle sensor, and prevents a decrease in the detection accuracy of the camshaft rotation angle.

The present invention relates to a cam angle sensor mounting structure for an internal combustion engine, which includes a cylinder head having an intake sidewall with an air intake port for drawing in intake air and an exhaust sidewall in which an exhaust gas outlet port for discharging exhaust gas is formed, a camshaft extending along the cylinder row direction and rotatably supported by the cylinder head, a cylinder head cover and an EGR housing portion attached to the cylinder head so as to cover the upper part of the cylinder head, and a cam angle sensor that detects the rotation angle of the camshaft, wherein the EGR housing portion has a first sidewall located on the exhaust sidewall side of the cylinder head, a second sidewall located on the intake sidewall side of the cylinder head, and the first sidewall. the cylinder head has a third side wall connecting the end of the first side wall in the cylinder row direction to the end of the second side wall in the cylinder row direction; a cylindrical mounting boss on which the cam angle sensor is mounted, and an upper wall connected to the upper end of the first side wall, the upper end of the second side wall, and the upper end of the third side wall; and a cylindrical EGR passage portion provided on the third side wall and having an EGR passage through which EGR gas flows, the EGR passage portion having an EGR gas inlet port provided on the first side wall for introducing EGR gas into the EGR passage and an EGR gas outlet port provided on the second side wall for discharging EGR gas from the EGR passage, and the mounting boss portion is connected to the EGR passage portion.

In this way, the present invention improves the rigidity around the mounting location of the cam angle sensor, suppressing vibration of the cam angle sensor and preventing a decrease in the detection accuracy of the camshaft rotation angle.

FIG. 1 is a left side view of an internal combustion engine according to an embodiment of the present invention. FIG. 2 is a front view of a cylinder head and a cylinder head cover of an internal combustion engine according to one embodiment of the present invention. FIG. 3 is a left side view of the cylinder head and cylinder head cover of the internal combustion engine according to one embodiment of the present invention. FIG. 4 is a plan view of an internal combustion engine according to an embodiment of the present invention, showing a state in which the cylinder head cover has been removed. FIG. 5 is a plan view of an EGR housing portion of an internal combustion engine according to one embodiment of the present invention. FIG. 6 is a plan view of an EGR housing portion of an internal combustion engine according to one embodiment of the present invention, showing a state in which the intake cam angle sensor and the exhaust cam angle sensor have been removed. FIG. 7 is a cross-sectional view taken along the line VII-VII in FIG.

The mounting structure for a cam angle sensor for an internal combustion engine according to one embodiment of the present invention is a mounting structure for a cam angle sensor for an internal combustion engine, which includes a cylinder head having an intake sidewall with an air intake port for drawing in intake air and an exhaust sidewall in which an exhaust gas outlet port for discharging exhaust gas is formed, a camshaft extending along the cylinder row direction and rotatably supported in the cylinder head, a cylinder head cover and an EGR housing portion attached to the cylinder head so as to cover the upper part of the cylinder head, and a cam angle sensor that detects the rotation angle of the camshaft, wherein the EGR housing portion has a first sidewall located on the exhaust sidewall side of the cylinder head and a second sidewall of the cylinder head. The cylinder head has a second sidewall located on the intake sidewall side, a third sidewall connecting the end of the first sidewall in the cylinder row direction to the end of the second sidewall in the cylinder row direction, a cylindrical mounting boss on which a cam angle sensor is mounted, an upper wall connected to the upper ends of the first sidewall, the second sidewall, and the third sidewall, and a cylindrical EGR passage section provided on the third sidewall side and having an EGR passage through which EGR gas flows. The EGR passage section has an EGR gas inlet port provided on the first sidewall for introducing EGR gas into the EGR passage and an EGR gas outlet port provided on the second sidewall for discharging EGR gas from the EGR passage, and the mounting boss section is connected to the EGR passage section.

As a result, the mounting structure for a cam angle sensor in an internal combustion engine according to one embodiment of the present invention improves the rigidity around the mounting location of the cam angle sensor, suppressing vibration of the cam angle sensor and preventing a decrease in the detection accuracy of the camshaft rotation angle.

The following describes a mounting structure for a cam angle sensor in an internal combustion engine according to one embodiment of the present invention, with reference to the drawings.

Figures 1 to 7 are diagrams showing the mounting structure of a cam angle sensor for an internal combustion engine according to one embodiment of the present invention. In Figures 1 to 7, the up, down, front, back, left, and right directions are based on the internal combustion engine installed in a vehicle, with the front-to-rear direction of the vehicle being the front-to-rear direction, the left-to-right direction of the vehicle (vehicle width direction) being the left-to-right direction, and the up and down direction of the vehicle (vehicle height direction) being the up and down direction.

First, the configuration will be described.
1, an engine 1 is provided in an engine compartment (not shown) of a vehicle. The engine 1 includes an engine body 2 and a chain cover 10 (see FIG. 4).

The engine body 2 has a cylinder block 3, a cylinder head 4, a cylinder head cover 5, and an oil pan 6, and a chain cover 10 is connected to the right end of the engine body 2. The engine 1 of this embodiment constitutes an internal combustion engine.

The cylinder block 3 is provided with multiple cylinders 3A (shown by phantom lines in Figure 4), and the cylinders 3A are arranged in the vehicle width direction. Hereinafter, the arrangement direction of the cylinders 3A (vehicle width direction) will be referred to as the cylinder row direction A.

Note that, although the engine 1 in this embodiment is a three-cylinder engine having three cylinders 3A, the number of cylinders is not limited to three.

Each cylinder 3A houses a piston (not shown), which is connected to the crankshaft 7 via a connecting rod (not shown) (see Figure 1). The crankshaft 7 has a central axis of rotation extending in the vehicle width direction and rotates around the central axis of rotation. The engine 1 in this embodiment is a transversely mounted engine with the crankshaft 7 extending in the vehicle width direction, and the vehicle is a front-engine, front-wheel drive (FF) vehicle.

The pistons reciprocate within the cylinders 3A, rotating the crankshaft 7 via the connecting rods. The cylinder head 4 is formed with multiple intake ports 4a (see Figure 4) and exhaust collection ports 4b (see Figure 3), both not shown.

Each intake port 4a is connected to a cylinder 3A and introduces intake air into the cylinder 3A. The exhaust collection section 4b is connected to each cylinder 3A through multiple exhaust ports (not shown).

In other words, the exhaust ports extend from each cylinder 3A to the exhaust collection section 4b, which collects the exhaust ports.

As shown by the phantom lines in Figure 2, the cylinder head 4 is provided with a cooling water passage 20, which extends from the right end to the left end of the cylinder head 4.

Cooling water is introduced into the right end of the cooling water passage 20 from a cooling water passage (not shown) formed in the cylinder block 3. The cooling water introduced into the cooling water passage 20 flows leftward along the cooling water passage 20. This allows the cylinder head 4 to be cooled by the cooling water. In this embodiment, the cooling water passage 20 constitutes the cooling water passage.

As shown in Figure 4, the cylinder head 4 has an intake side wall 4A where the intake port 4a opens, and an exhaust side wall 4B located on the opposite side (front side) of the intake side wall 4A and where the exhaust collection section 4b opens.

As shown in FIG. 3, the cylinder head 4 has a coolant discharge side wall 4C in which a coolant discharge port 4c is formed, through which coolant is discharged from the coolant passage 20. The coolant discharge side wall 4C is connected to the left end (end in the direction A of the cylinder row) of the intake side wall 4A and the left end (end in the direction A of the cylinder row) of the exhaust side wall 4B, and extends in the front-to-rear direction.

A cooling water branch unit (not shown) is connected to the cooling water outlet 4c, and the cooling water branch unit is connected to a radiator (not shown) and the cooling water inlet 13A of the EGR cooler 13 (see Figure 1) via a branch pipe (not shown).

The cooling water discharged from the cooling water outlet 4c is supplied to the radiator and the cooling water inlet 13A of the EGR cooler 13 via a cooling water branch unit and a cooling water pipe.

In this embodiment, the intake port 4a constitutes an air intake port through which intake air is drawn in, and the exhaust collection section 4b constitutes an exhaust gas outlet through which exhaust gas is discharged. That is, the cylinder head 4 has an intake side wall 4A with the intake port 4a and an exhaust side wall 4B with the exhaust collection section 4b.

As shown in Figure 1, an intake manifold 8 is attached to the intake side wall 4A. The intake manifold 8 has a surge tank 8A and three branch pipes 8B (one shown) corresponding to the number of cylinders 3A. An intake pipe (not shown) is connected to the surge tank 8A via a throttle body (not shown).

Intake air purified by an air cleaner (not shown) is introduced into the intake pipe, and the intake air is then introduced into the surge tank 8A through the throttle body.

The throttle body houses a throttle valve (not shown), which adjusts the amount of intake air introduced into the surge tank 8A.

Multiple branch pipes 8B extend from the surge tank 8A to each intake port 4a, distributing the intake air introduced into the surge tank 8A to each intake port 4a.

An exhaust purification device 9 is attached to the intake side wall 4A. Exhaust gas burned in the cylinder 3A is discharged from the cylinder 3A through the exhaust port and collected in the exhaust collection section 4b, from which it is then discharged to the exhaust purification device 9.

The exhaust purification device 9 purifies the exhaust gas emitted from the exhaust manifold 4b and releases it into the atmosphere through an exhaust pipe (not shown).

The engine 1 is equipped with an EGR (Exhaust Gas Recirculation) device 11. The EGR device 11 includes an upstream EGR pipe 12, an EGR cooler 13, an EGR valve 14, and a downstream EGR pipe 15.

The upstream end of the upstream EGR pipe 12 is connected to the exhaust purification device 9, and a portion of the exhaust gas from the exhaust purification device 9 is introduced into the upstream EGR pipe 12 as EGR gas. Here, upstream and downstream refer to the upstream and downstream directions of the flow of intake air, exhaust gas, and EGR gas.

The EGR valve 14 is located downstream of the upstream EGR pipe 12, and the upstream EGR pipe 12 is located upstream of the EGR valve 14.

The downstream end of the upstream EGR pipe 12 is connected to the upstream end of the EGR cooler 13. The EGR cooler 13 has a coolant inlet 13A that introduces coolant into the EGR cooler 13 and a coolant outlet 13B that discharges coolant from the EGR cooler 13.

The EGR cooler 13 cools the EGR gas introduced from the upstream EGR pipe 12 by exchanging heat between the EGR gas and the cooling water.

The downstream end of the EGR cooler 13 is connected to the EGR valve 14. The EGR valve 14 is attached to the EGR housing portion 25, and adjusts the flow rate of EGR gas flowing through the EGR passage portion 26, which will be described later.

The upstream end of the downstream EGR pipe 15 is connected to the EGR housing part 25, and EGR gas introduced into the EGR housing part 25 is discharged into the downstream EGR pipe 15. The downstream end of the downstream EGR pipe 15 is connected to the surge tank 8A, and EGR gas discharged into the downstream EGR pipe 15 is introduced into the surge tank 8A.

As shown in Figure 4, the cylinder head 4 is provided with an intake camshaft 16 and an exhaust camshaft 17, which extend parallel to the cylinder row direction A. The intake camshaft 16 and the exhaust camshaft 17 are provided with a plurality of intake cams 16A and exhaust cams 17A.

The intake cam 16A and exhaust cam 17A are installed at a distance in the cylinder row direction A, with one pair provided for each cylinder 3A.

The intake camshaft 16 and exhaust camshaft 17 are rotatably supported on the cylinder head 4 by cam caps 18 and 19, respectively.

Specifically, journal bearings (not shown) are provided on the top surface of the cylinder head 4, facing the cam caps 18 and 19. The intake camshaft 16 and exhaust camshaft 17 are rotatably attached to the cylinder head 4, sandwiched between the journal bearings and the cam caps 18 and 19, respectively. In this embodiment, the intake camshaft 16 and exhaust camshaft 17 form camshafts.

As shown in Figures 5 and 6, an EGR housing portion 25 is provided at the end (left end) of the cylinder head 4 in the cylinder alignment direction A. The EGR housing portion 25 is located on the opposite side of the cylinder head cover 5 from the chain cover 10. In other words, the EGR housing portion 25 is adjacent to the cylinder head cover 5 in the cylinder alignment direction A.

The cylinder head cover 5 is made of resin, and the EGR housing part 25 is made of metal such as aluminum die-cast.

The EGR housing portion 25 constitutes the first cylinder head cover, and the cylinder head cover 5 constitutes the second cylinder head cover. The EGR housing portion 25 and the cylinder head cover 5 constitute the cylinder head cover.

As shown in Figures 5 and 6, the EGR housing portion 25 has a front wall 25A, a rear wall 25B, a left side wall 25C, and an upper wall 25D.

As shown in Figure 3, the front wall 25A is located on the exhaust side wall 4B side of the cylinder head 4, and the rear wall 25B is located on the intake side wall 4A side of the cylinder head 4.

As shown in Figures 5 and 6, the left side wall 25C connects the left end of the front wall 25A (end in the direction of cylinder alignment A) to the left end of the rear wall 25B (end in the direction of cylinder alignment A), and the top wall 25D connects the top end of the front wall 25A, the top end of the rear wall 25B, and the top end of the left side wall 25C.

In this embodiment, the front wall 25A constitutes the first side wall, the rear wall 25B constitutes the second side wall, and the left side wall 25C constitutes the third side wall.

The EGR housing 25 is provided with an EGR passage 26. The EGR passage 26 is cylindrical, and has an EGR passage 26a formed therein through which EGR gas flows (see Figure 7). In this embodiment, the upstream EGR pipe 12, downstream EGR pipe 15, and EGR passage 26 constitute the EGR passage.

The EGR passage 26 has an EGR gas inlet 26b and an EGR gas outlet 26c. The EGR gas inlet 26b is provided in the front wall 25A (see Figure 2), and the EGR gas outlet 26c is provided in the rear wall 25B.

The EGR gas inlet 26b is the front (upstream) opening end of the EGR passage 26a, and the EGR gas outlet 26c is the rear (downstream) opening end of the EGR passage 26a.

In this embodiment, the EGR passage 26 extends linearly in a direction (front-to-rear direction) horizontally perpendicular to the cylinder row direction A, and is located outside (to the left of) the intake sidewall 4A in the cylinder row direction A. In other words, the EGR passage 26 is located away from the cylinder head cover 5 relative to the intake sidewall 4A in the cylinder row direction A.

The EGR passage portion 26 is not limited to extending linearly in a direction perpendicular to the horizontal direction of the cylinder rows A, but may extend at an angle relative to the direction of the cylinder rows A. Note that "horizontal" also includes a direction close to horizontal, i.e., a direction slightly inclined relative to the horizontal.

As shown in FIG. 2, a flange portion 25a is provided on the front wall 25A, and an EGR gas inlet port 26b is formed inside the flange portion 25a.

As shown in FIG. 1, the flange portion 14a of the EGR valve 14 is attached to the flange portion 25a. An EGR gas outlet (not shown) is provided inside the flange portion 14a, and the EGR gas discharged from the EGR valve 14 is introduced into the EGR passage 26a through the EGR gas inlet 26b.

As shown in Figures 5 and 6, a flange portion 25b is provided on the rear wall 25B, and an EGR gas discharge port 26c is formed inside the flange portion 25b.

As shown in FIG. 1, the flange portion 15a of the downstream EGR pipe 15 is attached to the flange portion 25b. An EGR gas inlet (not shown) is provided inside the flange portion 15a, and the EGR gas flowing through the EGR passage 26a is discharged into the downstream EGR pipe 15 through the EGR gas inlet of the flange portion 15a.

In other words, in the engine 1 of this embodiment, an EGR housing portion 25 is attached to the left end of the cylinder head 4, above the cylinder head 4, and EGR gas is introduced from the exhaust side to the intake side through an EGR passage portion 26 provided in the EGR housing portion 25.

As shown in FIG. 4, bosses 27A and 27B are provided at the front and rear ends of the left side wall 25C, and extend vertically along the left side wall 25C. Bosses 27F and 27G are provided on the front wall 25A and rear wall 25B, and extend vertically along the front wall 25A and rear wall 25B.

Bolt grooves (not shown) are provided at the upper left end of the cylinder head 4. Bolts 41A are inserted through bosses 27A, 27B, 27F, and 27G, and the bolts 41A are threaded into the bolt grooves in the cylinder head 4. This secures the EGR housing 25 to the cylinder head 4.

As shown in Figure 4, a flange portion 4F is provided at the upper end of the cylinder head 4. The flange portion 4F is provided around the periphery of the cylinder head 4, and the cylinder head 4 is open on the inside of the flange portion 4F. In other words, an opening 4h is formed at the top of the cylinder head 4.

A flange portion 10F is provided at the upper end of the chain cover 10, and the flange portion 10F is connected to the flange portion 4F.

The EGR housing portion 25 has a housing-side flange portion 25c, a front flange portion 25d, and a rear flange portion 25e.

As shown in FIG. 4, the housing-side flange portion 25c extends from the front wall 25A to the rear wall 25B, adjacent to the upper wall 25D. In other words, the housing-side flange portion 25c is connected to the right end portion of the upper wall 25D (the end portion on the chain cover 10 side).

The housing-side flange portion 25c has a curved portion 25p, which curves from the center of the extension direction of the housing-side flange portion 25c (the center in the front-to-rear direction) toward the left side wall 25C.

In this embodiment, the curved portion 25p makes the width of the front-to-rear center of the upper wall 25D in the direction of cylinder alignment A shorter than the width of the front side of the upper wall 25D in the direction of cylinder alignment A and the width of the rear side of the upper wall 25D in the direction of cylinder alignment A.

As a result, the area of the flat portion in the center of the upper wall 25D in the front-to-rear direction is smaller than the area of the front and rear sides of the upper wall 25D.

The front flange portion 25d is located at the upper end of the front wall 25A and extends from the front end of the housing flange portion 25c to the flange portion 4F, making contact with the flange portion 4F.

The rear flange portion 25e is located at the upper end of the rear wall 25B and extends from the rear end of the housing flange portion 25c to the flange portion 4F, making contact with the flange portion 4F.

As shown in Figures 2 and 3, a flange portion 5F is provided on the lower outer edge of the cylinder head cover 5, and the flange portion 5F extends along the flange portions 4F, 10F, 25c, 25d, and 25e. In other words, the flange portion 5F faces the flange portions 4F, 10F, 25c, 25d, and 25e in the vertical direction.

As shown in Figure 4, multiple bosses 4D are formed on the flange 4F, and the bosses 4D are spaced apart in the extension direction of the flange 4F.

Multiple bosses 10A are formed on the flange 10F, and the bosses 10A are spaced apart in the direction in which the flange 10F extends (see Figure 2).

Bosses 27C, 27D, and 27E are provided on the upper wall 25D of the EGR housing portion 25. Bosses 27C, 27D, and 27E protrude upward from the upper wall 25D and are connected to the housing-side flange portion 25c.

As a result, boss portions 27C, 27D, and 27E are connected to one another by housing-side flange portion 25c. In this embodiment, housing-side flange portion 25c constitutes the flange portion.

As shown in FIG. 2, the flange portion 5F of the cylinder head cover 5 has multiple boss portions 5A, which are spaced apart in the direction in which the flange portion 5F extends.

Bolts 41B and 41C are inserted through the multiple bosses 5A and 4D, and bosses 10A and 27C, 27D, and 27E, and the cylinder head cover 5 is fixed to the cylinder head 4 by bolts 41B and 41C.

In other words, the cylinder head cover 5 is fixed across the cylinder head 4, chain cover 10, and EGR housing portion 25, covering the opening 4h of the cylinder head 4.

As shown in Figure 6, mounting bosses 28A and 28B are provided on the upper wall 25D, and as shown in Figure 5, an exhaust cam angle sensor 31 and an intake cam angle sensor 32 are attached to the mounting bosses 28A and 28B, respectively.

The exhaust cam angle sensor 31 has a sensor body 31A fixed to the mounting boss portion 28A by a bolt 41D, and a connector 31B attached to the upper end of the sensor body 31A.

The intake cam angle sensor 32 has a sensor body 32A fixed to the mounting boss portion 28B by a bolt 41D, and a connector 32B attached to the upper end of the sensor body 32A. The exhaust cam angle sensor 31 and the intake cam angle sensor 32 have the same configuration and are compatible.

As shown in Figure 7, the sensor body 31A of the exhaust cam angle sensor 31 is attached to the mounting boss 28A via a seal member 29, preventing water or foreign matter from entering the EGR housing 25 between the sensor body 31A and the mounting boss 28A.

In addition, a sealing member (not shown) is interposed between the sensor body 32A of the intake cam angle sensor 32 and the mounting boss portion 28B. In this embodiment, the exhaust cam angle sensor 31 and the intake cam angle sensor 32 constitute a cam angle sensor.

As shown in Figure 4, an intake-side sensing rotor 16S and an exhaust-side sensing rotor 17S are attached to the left ends of the intake camshaft 16 and the exhaust camshaft 17, and the intake-side sensing rotor 16S and the exhaust-side sensing rotor 17S are located below the upper wall 25D of the EGR housing portion 25.

Protrusions (not shown) are formed on the outer periphery of the intake-side sensing rotor 16S and the exhaust-side sensing rotor 17S, and the protrusions are formed in a unique pattern for each cylinder 3A.

The exhaust cam angle sensor 31 and intake cam angle sensor 32 face the intake-side sensing rotor 16S and exhaust-side sensing rotor 17S in the vertical direction, and the sensor body 31A detects the protrusions on the intake-side sensing rotor 16S and exhaust-side sensing rotor 17S to detect the rotational angle (rotational phase) of the intake camshaft 16 and exhaust camshaft 17.

Connectors 31B and 32B are connected to a controller via a wire harness (not shown), and information regarding the cam angle detected by sensor bodies 31A and 32A is transmitted from connectors 31B and 32B to a controller (not shown) via the wire harness.

As shown in Figures 6 and 7, the mounting bosses 28A and 28B are connected to the EGR passage 26.

As shown in FIG. 7, the lower end portions 28a of the mounting boss portions 28A, 28B are located above the lower end portion 26d of the EGR passage portion 26 and below the upper end portion 26e of the EGR passage portion 26, and the upper end portions 28b of the mounting boss portions 28A, 28B are located above the upper end portion 26e of the EGR passage portion 26.

In other words, the upper end 26e of the EGR passage portion 26 is located higher than the lower end 28a of the mounting boss portions 28A and 28B.

Although the mounting boss portion 28B is not shown in Figure 7, the positional relationship between the mounting boss portion 28B and the EGR passage portion 26 is the same as the positional relationship between the mounting boss portion 28A and the EGR passage portion 26. The mounting boss portion 28B is located on the far side (rear side) of the mounting boss portion 28A in Figure 7. Therefore, in Figure 7, the mounting boss portion 28B located on the far side of the mounting boss portion 28A is indicated by an imaginary line.

As shown in FIG. 4, boss portion 27C is located on the EGR passage portion 26 side relative to boss portions 27D and 27E, and is connected to the EGR passage portion 26.

Boss portion 27D is provided on upper wall 25D on the front wall 25A side relative to boss portion 27C, and is located closer to the front wall 25A than mounting boss portion 28A.

Boss portion 27E is provided on upper wall 25D on the rear wall 25B side relative to boss portion 27C, and is located closer to the rear wall 25B than mounting boss portion 28B.

In this embodiment, boss portion 27C constitutes the fastening portion and the first fastening portion, boss portion 27D constitutes the fastening portion and the second fastening portion, boss portion 27E constitutes the fastening portion and the third fastening portion, and bolt 41C constitutes the fastener.

Mounting boss portion 28A is located between boss portion 27C and boss portion 27D. Specifically, mounting boss portion 28A is located between boss portion 27C and boss portion 27D so as to pass through imaginary line 42A connecting boss portion 27C and boss portion 27D. In other words, mounting boss portion 28A is sandwiched between boss portion 27C and boss portion 27D.

Mounting boss portion 28B is located between boss portion 27C and boss portion 27E. Specifically, mounting boss portion 28B is located between boss portion 27C and boss portion 27E so as to pass through imaginary line 42B connecting boss portion 27C and boss portion 27E. In other words, mounting boss portion 28B is sandwiched between boss portion 27C and boss portion 27E.

Mounting boss 28A overlaps boss 27D in the cylinder alignment direction A, and mounting boss 28B overlaps boss 27E in the cylinder alignment direction A. In other words, mounting bosses 28A, 28B, boss 27D, and boss 27E overlap in the cylinder alignment direction A.

In other words, mounting bosses 28A, 28B, boss 27D, and boss 27E are arranged side by side in a direction (front-to-rear direction) that is horizontally perpendicular to cylinder row direction A.

Next, the effects of the mounting structure of the cam angle sensor for the engine 1 according to this embodiment will be described.
In the mounting structure of the cam angle sensor for the engine 1 of this embodiment, an EGR housing portion 25 is mounted to the cylinder head 4. The EGR housing portion 25 has a front wall 25A located on the exhaust side wall 4B side of the cylinder head 4, a rear wall 25B located on the intake side wall 4A side of the cylinder head 4, and a left side wall 25C connecting the left end of the front wall 25A in the cylinder row direction A to the left end of the rear wall 25B in the cylinder row direction A.

The EGR housing portion 25 also has mounting bosses 28A and 28B to which an exhaust cam angle sensor 31 and an intake cam angle sensor 32 are attached, an upper wall 25D connected to the upper end of the front wall 25A, the upper end of the rear wall 25B, and the upper end of the left side wall 25C, and a cylindrical EGR passage portion 26 provided on the left side wall 25C and having an EGR passage 26a through which EGR gas flows.

The EGR passage section 26 is provided in the front wall 25A with an EGR gas inlet 26b that introduces EGR gas into the EGR passage 26a, and in the rear wall 25B with an EGR gas outlet 26c that discharges EGR gas from the EGR passage 26a. Mounting bosses 28A and 28B are connected to the EGR passage section 26.

In this way, by connecting the mounting bosses 28A, 28B to the highly rigid cylindrical EGR passage 26, the mounting bosses 28A, 28B can be reinforced by the EGR passage 26, increasing the rigidity of the mounting bosses 28A, 28B.

This increases the support rigidity of the exhaust cam angle sensor 31 and intake cam angle sensor 32 attached to the mounting bosses 28A and 28B, and prevents the exhaust cam angle sensor 31 and intake cam angle sensor 32 from vibrating due to vibrations of the engine 1. As a result, it is possible to prevent a decrease in the accuracy with which the exhaust cam angle sensor 31 and intake cam angle sensor 32 detect the rotation angles of the intake camshaft 16 and exhaust camshaft 17.

Furthermore, according to the mounting structure of the cam angle sensor for the engine 1 of this embodiment, the upper end 26e of the EGR passage portion 26 is located higher than the lower end 28a of the mounting boss portions 28A and 28B.

This allows the upper end 26e of the EGR passage section 26, which is formed in an arc shape, to bulge out from the upper wall 25D of the EGR housing section 25. Therefore, the upper end 26e of the EGR passage section 26 reduces the flat portion of the upper wall 25D.

This increases the surface rigidity of the upper wall 25D, preventing the upper wall 25D from vibrating due to vibrations of the engine 1. This further increases the support rigidity of the exhaust cam angle sensor 31 and the intake cam angle sensor 32, more effectively preventing the exhaust cam angle sensor 31 and the intake cam angle sensor 32 from vibrating.

As a result, it is possible to more effectively prevent a decrease in the detection accuracy of the rotation angles of the intake camshaft 16 and the exhaust camshaft 17 by the exhaust cam angle sensor 31 and the intake cam angle sensor 32.

Furthermore, according to the mounting structure for the cam angle sensor of the engine 1 of this embodiment, the EGR housing portion 25 has a housing-side flange portion 25c that contacts the flange portion 4F of the cylinder head 4, and the housing-side flange portion 25c extends from the front wall 25A to the rear wall 25B so as to be adjacent to the upper wall 25D.

In addition, the housing-side flange portion 25c has a curved portion 25p that curves toward the left side wall 25C.

This reduces the width between the curved portion 25p and the EGR passage portion 26 in the cylinder row direction A, thereby reducing the flat portion of the upper wall 25D.

This further increases the surface rigidity of the upper wall 25D, more effectively preventing the upper wall 25D from vibrating due to vibrations of the engine 1.

This further increases the support rigidity of the exhaust cam angle sensor 31 and the intake cam angle sensor 32, and more effectively suppresses vibration of the exhaust cam angle sensor 31 and the intake cam angle sensor 32.

As a result, it is possible to more effectively prevent a decrease in the detection accuracy of the rotation angles of the intake camshaft 16 and the exhaust camshaft 17 by the exhaust cam angle sensor 31 and the intake cam angle sensor 32.

Furthermore, according to the cam angle sensor mounting structure for the engine 1 of this embodiment, the EGR housing portion 25 has boss portions 27C, 27D, and 27E that are fastened to the cylinder head cover 5 by bolts 41C, and the boss portions 27C, 27D, and 27E are provided on the upper wall 25D.

In addition, mounting boss portion 28A is provided between boss portion 27C and boss portion 27D, and mounting boss portion 28B is provided between boss portion 27C and boss portion 27E.

In this embodiment, boss portions 27C, 27D, and 27E are attached to the cylinder head cover 5 by bolts 41C, which provides high rigidity. This increases the rigidity of the upper wall 25D around boss portions 27C, 27D, and 27E, making the upper wall 25D around boss portions 27C, 27D, and 27E less susceptible to vibration.

Therefore, by providing mounting boss portion 28A between boss portion 27C and boss portion 27D, which have high rigidity, and by providing mounting boss portion 28B between boss portion 27C and boss portion 27E, which have high rigidity, the rigidity of mounting boss portions 28A and 28B can be further increased.

This further increases the support rigidity of the exhaust cam angle sensor 31 and the intake cam angle sensor 32, and more effectively suppresses vibration of the exhaust cam angle sensor 31 and the intake cam angle sensor 32.

As a result, it is possible to more effectively prevent a decrease in the detection accuracy of the rotation angles of the intake camshaft 16 and the exhaust camshaft 17 by the exhaust cam angle sensor 31 and the intake cam angle sensor 32.

Furthermore, according to the mounting structure of the cam angle sensor for the engine 1 of this embodiment, mounting boss portion 28A overlaps boss portion 27D in the cylinder row direction A, and mounting boss portion 28B overlaps boss portion 27E in the cylinder row direction A.

This allows the highly rigid bosses 27D, 27D to be placed closer to the mounting bosses 28A, 28B, further increasing the rigidity of the upper wall 25D around the mounting bosses 28A, 28B.

This further increases the rigidity of the mounting bosses 28A and 28B, thereby further increasing the support rigidity of the exhaust cam angle sensor 31 and the intake cam angle sensor 32.

This more effectively prevents the exhaust cam angle sensor 31 and the intake cam angle sensor 32 from vibrating, and more effectively prevents a decrease in the accuracy with which the exhaust cam angle sensor 31 and the intake cam angle sensor 32 detect the rotation angles of the intake camshaft 16 and the exhaust camshaft 17.

Furthermore, according to the cam angle sensor mounting structure for the engine 1 of this embodiment, the boss portion 27C is connected to the EGR passage portion 26.

In addition, boss portion 27D is provided on top wall 25D on the front wall 25A side relative to boss portion 27C, and boss portion 27E is provided on top wall 25D on the rear wall 25B side relative to boss portion 27C.

In this way, by connecting the highly rigid boss portion 27C to the highly rigid EGR passage portion 26, the surface rigidity of the upper wall 25D can be further increased.

In addition, the connecting portions between the top wall 25D and the front wall 25A and the connecting portions between the top wall 25D and the rear wall 25B are bent, resulting in high rigidity. Therefore, by providing the boss portion 27D on the top wall 25D on the front wall 25A side, which has high rigidity, and the boss portion 27E on the top wall 25D on the rear wall 25B side, which has high rigidity, the surface rigidity of the top wall 25D can be further increased.

This more effectively prevents the upper wall 25D from vibrating due to engine 1 vibration. This further increases the support rigidity of the exhaust cam angle sensor 31 and the intake cam angle sensor 32, more effectively preventing the exhaust cam angle sensor 31 and the intake cam angle sensor 32 from vibrating.

As a result, it is possible to more effectively prevent a decrease in the detection accuracy of the rotation angles of the intake camshaft 16 and the exhaust camshaft 17 by the exhaust cam angle sensor 31 and the intake cam angle sensor 32.

Furthermore, according to the mounting structure for the cam angle sensor of the engine 1 of this embodiment, the boss portions 27C, 27D, and 27E are connected to the housing side flange portion 25c, so the highly rigid boss portions 27C, 27D, and 27E can reinforce the housing side flange portion 25c, thereby increasing the rigidity of the housing side flange portion 25c.

This further increases the rigidity of the boss portions 27C, 27D, and 27E and the upper wall 25D around the housing-side flange portion 25c, more effectively suppressing vibration of the upper wall 25D.

This further increases the rigidity of the mounting bosses 28A and 28B, thereby further increasing the support rigidity of the exhaust cam angle sensor 31 and the intake cam angle sensor 32.

As a result, vibration of the exhaust cam angle sensor 31 and the intake cam angle sensor 32 can be more effectively suppressed, and a decrease in the detection accuracy of the rotation angles of the intake camshaft 16 and the exhaust camshaft 17 by the exhaust cam angle sensor 31 and the intake cam angle sensor 32 can be more effectively prevented.

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

1...engine (internal combustion engine), 4...cylinder head, 4A...intake side wall, 4a...intake port (air intake port), 4B...exhaust side wall, 4b...exhaust collection section (exhaust gas exhaust port), 5...cylinder head cover, 16...intake camshaft (camshaft), 17...exhaust camshaft (camshaft), 25...EGR housing section, 25A...front wall (first side wall), 25B...rear wall (second side wall), 25C...left side wall (third side wall), 25c...housing side flange section (flange section), 25D...upper wall, 25p...curved section, 2 6...EGR passage, 26a...EGR passage, 26b...EGR gas inlet, 26c...EGR gas outlet, 26e...upper end (upper end of EGR passage), 27C...boss portion (fastening portion, first fastening portion), 27D...boss portion (fastening portion, second fastening portion), 27E...boss portion (fastening portion, third fastening portion), 28A, 28B...mounting boss portion, 28a...lower end of mounting boss portion, 31...exhaust cam angle sensor (cam angle sensor), 32...intake cam angle sensor (cam angle sensor), 41C...bolt (fastener), A...cylinder alignment

Claims (6)

a cylinder head having an intake side wall having an air intake port for drawing in intake air and an exhaust side wall having an exhaust gas exhaust port formed therein through which exhaust gas is discharged;
a camshaft extending along the cylinder row direction and rotatably supported by the cylinder head;
a cylinder head cover and an EGR housing portion attached to the cylinder head so as to cover an upper portion of the cylinder head;
a cam angle sensor for detecting a rotation angle of the camshaft,
the EGR housing portion includes a first sidewall located on the exhaust sidewall side of the cylinder head, a second sidewall located on the intake sidewall side of the cylinder head, a third sidewall connecting an end of the first sidewall in the cylinder row direction to an end of the second sidewall in the cylinder row direction, an upper wall having a cylindrical mounting boss portion on which the cam angle sensor is mounted and connected to an upper end of the first sidewall, an upper end of the second sidewall, and an upper end of the third sidewall, and a cylindrical EGR passage portion provided on the third sidewall side and having an EGR passage through which EGR gas flows,
the EGR passage portion has an EGR gas inlet port provided in the first side wall for introducing EGR gas into the EGR passage, and an EGR gas outlet port provided in the second side wall for discharging EGR gas from the EGR passage,
11. A mounting structure for a cam angle sensor of an internal combustion engine, wherein the mounting boss portion is connected to the EGR passage portion. The mounting structure for a cam angle sensor in an internal combustion engine according to claim 1, characterized in that the upper end of the EGR passage portion is located higher than the lower end of the mounting boss portion. the EGR housing portion has a plurality of fastening portions that are fastened to the cylinder head cover by fasteners,
the plurality of fastening portions are provided on the upper wall,
3. The mounting structure for a cam angle sensor of an internal combustion engine according to claim 1, wherein the mounting boss portion is provided between at least two fastening portions. At least one of the plurality of fastening portions has a first fastening portion connected to the EGR passage portion,
4. The mounting structure for a cam angle sensor of an internal combustion engine according to claim 3, wherein the plurality of fastening portions include a second fastening portion provided on the upper wall on the first side wall side relative to the first fastening portion, and a third fastening portion provided on the upper wall on the second side wall side relative to the first fastening portion. the EGR housing portion has a flange portion that contacts the cylinder head cover, the flange portion extending from the first side wall to the second side wall so as to be adjacent to the top wall,
5. The mounting structure for a cam angle sensor of an internal combustion engine according to claim 3, wherein the flange portion has a curved portion that curves toward the third side wall. The mounting structure for a cam angle sensor in an internal combustion engine as described in claim 5, wherein the multiple fastening portions are connected to the flange portion.