JP2015145630A - internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent heat damage from an exhaust system member from being inflicted on a cam angle sensor provided on one side of a cylinder head.SOLUTION: An assembly unit 6b of an exhaust manifold 6 is suspended via a stay 14 and the stay 14 is fixed to a cooling water inlet portion 12a of a cooling water distribution device 12 provided on one side 2c of a cylinder head 2. A cam angle sensor 21 is disposed on the stay 14 and a shield member 23 is fixed to an auxiliary piece 26 provided on the stay 14. Even if heat of the exhaust manifold 6 or the like heats the shield member 23, the heat is released to the cooling water inlet portion 12a via the stay 14 and absorbed by the cooling water. Owing to this, it is possible to prevent the shield member 23 from being heated and prevent heat damage from being inflicted on the cam angle sensor 21.

Description

  The present invention relates to an internal combustion engine in which a sensor and a cooling water distributor are arranged at one end of a cylinder head.

  A cylinder head of an internal combustion engine is generally provided with a cam angle sensor that detects a rotation angle (rotation phase) of a cam shaft. As an example, Patent Document 1 describes that a cam angle sensor is arranged on one end face of a cylinder head facing a direction of a crank axis.

JP 2001-73826 A

  An exhaust manifold is fixed to the cylinder head, and the exhaust manifold is fixed to one side surface of the cylinder head that faces in a direction orthogonal to the crank axis. The exhaust manifold is connected to a member such as an exhaust pipe or a catalyst case. Depending on the structure of the internal combustion engine, a cam angle sensor may be located above or near the heat of the exhaust manifold or the exhaust pipe (especially radiant heat). For example, the cam angle sensor provided at one end of the cylinder head may be exposed to heat from the exhaust manifold or the like.

  In this regard, it can be said that a shielding member that protects the cam angle sensor from heat such as the exhaust manifold may be attached to the cylinder head. However, since the cylinder head becomes hot, the heat is transferred to the shielding member and the shielding member becomes hot. If it becomes, there exists a possibility that a shielding member may become a heat source and a cam angle sensor may receive heat damage. In particular, when receiving heat from the catalyst case, since the amount of heat is large, the temperature rise of the shielding member may become remarkable.

  The present invention is made in view of such a current situation, and aims to prevent or remarkably suppress thermal damage to the sensor.

  According to the present invention, an exhaust system member is connected to one side surface of the outer surface of the cylinder head that is long in the direction of the crank axis, and the coolant distribution is provided to one end portion of the cylinder head that faces in the direction of the crank axis. In a configuration in which the device and the cam angle sensor or other sensor are arranged, a shielding member that protects the sensor from the heat of the exhaust system member is directly or indirectly through the cooling water distributor. Is attached. The sensor is a concept including a harness (cable).

  The invention of the present application also includes the configurations of claims 2 and 3. In the invention of claim 2, in claim 1, the shielding member is attached to a cooling water outflow portion of the cooling water distributor. On the other hand, according to a third aspect of the present invention, in the first aspect, the shielding member is attached to a cooling water inflow portion of the cooling water distributor.

  According to the present invention, even if the shielding member receives heat by the exhaust system member, the heat can be released from the cooling water distributor to the cooling water. For this reason, it can prevent that a shielding member heats up and a sensor receives a heat damage.

  If the configuration of claim 2 is adopted, heat can be transferred to the cooling water flowing out from the cooling water distribution device, so that heat can be transferred to the cooling water that circulates during the warm-up operation, contributing to early warm-up, and thus improving fuel efficiency. Can contribute. In the case of an internal combustion engine for a vehicle, the cooling water that has passed through the cylinder head or the like goes from the outflow portion of the cooling water distributor to the heater for heating the vehicle interior. Since the temperature can be increased, there is an advantage that the performance of the heater can be improved.

  On the other hand, when the cooling water is cooled by the radiator or absorbed by the heater, the cooled cooling water flows into the cooling water inflow portion of the cooling water distributor, so that the cooling performance of the shielding member is improved and the sensor is improved. The heat damage prevention function is further ensured.

1 is a partial side view of an internal combustion engine according to an embodiment. (A) is a partial front view of the internal combustion engine in a state where the shielding member is separated, and (B) is a perspective view of the shielding member. (A) is the fragmentary front view of the principal part, (B) is BB sectional drawing of (A).

  Next, an embodiment of the present invention will be described with reference to the drawings. The present embodiment is applied to an internal combustion engine for a vehicle, and the internal combustion engine includes a cylinder block 1 as a core of the engine body and a cylinder head 2 fixed to the top surface of the cylinder block 1. The cylinder head cover 3 is fixed to the surface. As shown in FIG. 2, the internal combustion engine of the present embodiment has a slant shape that is greatly inclined so that the axis 4 of the cylinder bore approaches the horizontal.

  Accordingly, in the cylinder head 2, the two side surfaces 2a and 2b facing the direction orthogonal to the cylinder bore axis 4 and the crank axis direction (or cylinder row direction) 5 are directed downward and upward, and directed downward. An exhaust manifold 6 is fixed to one side surface 2a, and an intake manifold (not shown) is fixed to the other side surface 2b facing upward.

  As shown in FIG. 1, the internal combustion engine of this embodiment has three cylinders, and three exhaust holes 7 are arranged in the crankshaft direction 5 on one side surface 2 a of the cylinder head 2. Therefore, the exhaust manifold 6 has three branch pipes 6a and one collecting pipe 6b, and the exhaust pipe 8 is connected to the collecting pipe 6b by the first and second flanges 9 and 10. The first flange plate 9 is welded to the collecting portion 6b of the exhaust manifold 6, and the second flange plate 10 is welded to the exhaust pipe 8, both of which are fixed by bolts (not shown). Most of the exhaust manifold 6 is covered with an insulator 11.

  The collective portion 6b of the exhaust manifold 6 is pulled out to one side in the crank axis direction 5, and therefore the collective portion 6b is located on one side of the cylinder head 2 in the crank axis direction 5. The one end (one end face) 2c is located.

  A cooling water distribution device 12 is provided at one end 2 c of the cylinder head 2, and a cooling water inflow portion 12 a of the cooling water distribution device 12 projects in the crank axis direction 5. The cooling water distributor 12 also enters the cylinder head 2. The first flange plate 9 fixed to the collecting portion 6 b of the exhaust manifold 6 is fixed to the cooling water inflow portion 12 a via the stay 13.

  That is, the upper end portion of the stay 13 is fixed to the outer end surface of the cooling water inflow portion 12 a with the bolt 15, and the lower end portion of the stay 13 is fixed to the first flange plate 9 with the bolt 17. Since the outer end surface of the cooling water inflow portion 12a is further away from the cylinder head 2 in the crank axis direction 5 than the first flange plate 9, the stay 13 is bent in a side view. A heater return pipe 19 is connected to the cooling water inflow portion 12 a of the cooling water distributor 12.

  Rotation of the camshaft that drives the intake valve and the exhaust valve is located at a portion of the one end portion 2c of the cylinder head 2 that is slightly closer to the cylinder head cover 3 side and the other side surface 2b than the coolant distributor 12 in front view. A cam angle sensor 21 for detecting the phase (rotation angle) is arranged. Of course, a harness 22 is connected to the cam angle sensor 21.

  The cam angle sensor 21 is located approximately on the collective portion 6 b of the exhaust manifold 6. For this reason, the cam angle sensor 21 receives heat 31 from the collective portion 6 b of the exhaust manifold 6. Therefore, a shielding member 23 made of a metal plate that guards heat from the collective portion 6b of the exhaust manifold 6 is provided below the cam angle sensor 21.

  The shielding member 23 includes a shielding portion 24 that is positioned below the cam angle sensor 21 and spreads in a substantially horizontal shape, and a bracket portion 25 that is disposed in the vicinity of the one side portion 2c of the cylinder head 2. Yes. Therefore, it has a substantially L-shaped form.

  The bracket portion 25 is configured to extend toward the upper portion of the stay 14, and the stay 14 is provided with a laterally facing piece 14a facing outward from the bracket portion 25, and an auxiliary plate 26 is welded to the upper surface of the laterally facing piece 14a. ing. It is also possible to provide the auxiliary piece 26 integrally with the stay 14.

  The bracket portion 25 overlaps the auxiliary piece 26 from below. A positioning groove 28 that opens outward is formed at the front end of the bracket portion 25, and the positioning groove 28 is fitted into the lateral piece 14 a of the stay 14, and further, a nut 29 is formed on the inner surface of the bracket portion 25. And the auxiliary piece 26 is fixed to the nut with a bolt 30. For this reason, the shielding member 23 is fixed to the auxiliary piece 26 in a state where the shielding member 23 is positioned so as not to rotate around the axis of the nut 29. The shield part 24 faces the cylinder head 2 from the bracket part 25.

  In the above configuration, since the shielding member 23 is disposed between the cam angle sensor 21 (and its harness 22) and the exhaust manifold 6 and the exhaust pipe 8, the heat 31 from the exhaust manifold 6 and the exhaust pipe 8 is It is blocked by the shielding part 24 of the shielding member 23. The shielding member 23 receives the heat 31 and rises in temperature. However, since the heat of the shielding member 23 escapes to the cooling water inflow portion 12a of the cooling water distributor 12 through the stay 14, the shielding member 23 increases in temperature. Thus, it can be prevented that the cam angle sensor 21 becomes a heat source.

  That is, the shielding member 23 is cooled by the cooling water via the stay 14, and therefore, it is possible to prevent the shielding member 23 from being heated to a high sound that causes thermal damage to the cam angle sensor 21. As a result, the protective function of the cam angle sensor 21 can be fully exerted, and a situation such as malfunction or malfunction of the cam angle sensor 21 can be prevented.

  The shielding member 23 can also be positioned by being fixed to the auxiliary piece 26 with two bolts 30. However, when the method of fitting the engaging groove 28 into the lateral piece 14a as in the embodiment is adopted, There is an advantage that positioning can be performed reliably while the bolt 30 is fastened. Of course, other positioning means may be employed.

  The upper shielding member 23 may be fixed to the location of the cooling water inflow portion of the cooling water distributor 12, or the bracket portion 25 of the shielding member 23 is formed in a bifurcated manner, and these are connected to the cooling water outflow portion and the cooling water. You may fix to both an inflow part. Also in this case, it may be fixed directly, or may be fixed via another member such as a stay.

  It is also possible to close the gap between the shielding member 23 and the cylinder head 2 with a heat insulating material such as glass wool. In the shielding member, another sensor different from the cam angle sensor may be protected, or the cam angle sensor and the other sensor may be protected.

  The present invention can actually be embodied in an internal combustion engine. Therefore, it can be used industrially.

1 Cylinder block 2 Cylinder head 4 Cylinder bore axis 5 Crank axis direction (cylinder row axis)
6 Exhaust Manifold 8 Exhaust Pipe 9 First Flange Plate 12 Cooling Water Distributor 12a Cooling Water Outflow Portion 14 Stay 14a Lateral Piece 21 Sensor Angle Sensor 22 as an Example of Sensor 22 Sensor Harness 23 Shielding Member 24 Shielding Portion 26 Auxiliary Piece 25 Bracket Part 28 Engaging groove 29 Nut 30 Bolt

Claims (3)

An exhaust system member is connected to one side of the outer surface of the cylinder head that is long in the direction of the crank axis, and a cooling water distributor and a cam angle sensor or other sensor Is a configuration in which
A shielding member for protecting the sensor from the heat of the exhaust system member is attached to the cooling water distributor directly or indirectly through another member;
Internal combustion engine. The shielding member is attached to a cooling water outflow portion of the cooling water distributor.
The internal combustion engine according to claim 1. The shielding member is attached to a cooling water inflow portion of the cooling water distributor.
The internal combustion engine according to claim 1.

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