JP5199928B2 - Internal combustion engine with engine cover - Google Patents

Description

  The present invention provides an engine that covers a space between first and second intake devices connected to first and second banks, a first intake chamber provided in the first intake device, and a second intake chamber provided in the second intake device. An internal combustion engine provided with a cover.

  In an internal combustion engine including first and second intake devices respectively connected to first and second banks, the first intake chamber of the first intake device and the second intake chamber of the second intake device are separated from each other. It is known to have an engine cover that, when placed, covers between the first and second intake chambers. (For example, see Patent Document 1)

Japanese Utility Model Publication No. 3-59419

When the first and second intake chambers of the first and second intake devices connected to the first and second banks are spaced apart from each other, the first and second intake devices for the first and second banks are provided. Due to the variation in the assembly accuracy and the variation in the assembly accuracy of the plurality of devices constituting the first and second intake devices, the positions of the two intake chambers may vary. For this reason, in an internal combustion engine in which an engine cover disposed between the first and second intake chambers so as to cover the space between the first and second intake chambers is fixed to the two intake chambers, the positions of the first and second intake chambers vary. For this reason, it takes time to fix the engine cover, and a fixing structure that can absorb variations in both intake chambers is required as the engine cover fixing structure. May be invited.
In addition, the first and second intake chambers are variable cylinder internal combustion engines in which the cylinders in the first bank of the first and second banks are in an operating state, while the cylinders in the second bank are operated in a cylinder-free state. In the case where it is provided, the heat generation amount in the first bank and the second bank is different at the time of partial cylinder operation in which the second bank (resting bank) is in the cylinder resting state, which is caused by the difference in heat transfer amount due to heat conduction of combustion heat. Thus, the first and second intake chambers are displaced by the difference in thermal expansion between the first and second banks and the difference in thermal expansion between the first and second intake devices.
Further, when the circulation of intake air in the second intake device connected to the second bank in the cylinder deactivation state is interrupted during partial cylinder operation, the first intake chamber connected to the first bank is While the cooling effect by the intake air flowing through the first intake chamber is maintained at a relatively low temperature, the intake air does not flow in the second intake chamber connected to the second bank. Due to heat dissipation from one bank and the like, the temperature becomes higher than that of the first intake chamber, so that the first and second intake chambers are displaced by thermal expansion corresponding to the respective temperatures.
As described above, when both intake chambers are displaced due to thermal expansion of each intake device including each bank and each intake chamber caused by combustion heat during operation of the internal combustion engine, the displacement is not applied to the engine cover fixed to both intake chambers. The engine cover may be deformed or the durability of the engine cover may be reduced. Therefore, in order to reduce this stress, the engine cover fixing structure needs to be able to absorb the displacement due to thermal expansion, which also increases the number of parts and the cost.

  This invention is made | formed in view of such a situation, and the invention of Claims 1-5 improves the assembly | attachment property of the engine cover arrange | positioned between the 1st, 2nd intake chamber, and The purpose is to reduce the cost by simplifying the engine cover fixing structure. The invention according to claim 2 further improves the durability of the engine cover by suppressing the generation of stress in the engine cover due to the displacement of the intake chamber caused by the thermal expansion of the bank or the intake device. For this purpose, the invention described in claims 3 and 4 further aims to improve the durability of the engine cover by lowering the thermal influence on the engine cover. The purpose is to improve the durability of the engine cover by reducing the vibration of the cover.

The invention according to claim 1 is the first bank (B1) and the second bank (B2), the first intake chamber (21) of the first intake device (N1) connected to the first bank (B1), and The second intake chamber (31) of the second intake device (N2) connected to the second bank (B2), the first intake chamber (21) and the second intake chamber ( 31) and an engine cover (50) disposed between the engine cover (50), the engine cover (50) being one of the first intake chamber (21) and the second intake chamber (31). The internal combustion engine is fixed only to one intake chamber (21 or 31).
The invention according to claim 2 is the internal combustion engine according to claim 1, wherein the first cylinder (2a) of the first bank (B1) and the second cylinder (3a) of the second bank (B2) are put into operation. Cylinder deactivation means (45) for switching the operation mode between a first operation mode to be performed and a second operation mode in which the first cylinder (2a) is in an operating state and the second cylinder (3a) is in a cylinder deactivation state. Is provided.
According to a third aspect of the present invention, in the internal combustion engine according to the second aspect, the cylinder deactivation means (45) interrupts the flow of intake air in the second intake device (N2) when in the cylinder deactivation state. An intake flow blocking mechanism is provided, and the one intake chamber (21 or 31) is the first intake chamber (21).
According to a fourth aspect of the present invention, in the internal combustion engine according to the third aspect, the intake flow blocking mechanism includes an intake valve (14b) and an exhaust valve (14) provided in the second bank (B2) in the rest state. 15b) is a valve pause mechanism (46) that keeps the valve closed.
According to a fifth aspect of the present invention, in the internal combustion engine according to the second aspect, the one intake chamber (21 or 31) is the second intake chamber (31).

According to the first aspect of the present invention, the engine cover disposed so as to cover the space between the first and second intake chambers spaced apart from each other is provided only in one of the first and second intake chambers. Because it is fixed, due to variations in the assembly accuracy of the first and second air intake devices with respect to the first and second banks, and variations in the assembly accuracy of a plurality of devices constituting the first and second air intake devices Even when the positions of the first and second intake chambers vary, the engine cover can be fixed to one intake chamber without being restricted by the position of the other intake chamber in the first and second intake chambers. As a result, the assembly of the engine cover is facilitated and its assemblability is improved, and the fixing structure to the intake chamber is simplified, thereby reducing the cost.
According to the second aspect of the present invention, during the partial cylinder operation in which the second bank is in the cylinder deactivation state, the heat generated in the first and second banks is caused by the difference in the amount of heat generated in the first bank and the second bank. Even if the first and second intake chambers are displaced due to expansion differences or thermal expansion differences between the first and second intake devices, the engine cover is fixed to only one of the first and second intake chambers. Therefore, the displacement of the engine cover due to the displacement is suppressed, and the durability of the engine cover is improved.
According to the third aspect of the present invention, the second intake device in which the flow of the intake air is blocked is the first intake device that is in the operating state as compared with the first intake device that is cooled by the flowing intake air and is relatively cool. The engine cover is fixed only to the first intake chamber, which is relatively low in temperature, due to heat dissipation from the bank, so the heat effect on the engine cover can be reduced and its durability is improved. it can.
According to a fourth aspect of the invention, in the internal combustion engine in which the flow of the intake air in the second intake device is interrupted by a valve deactivation mechanism that keeps the intake valve and the exhaust valve in a closed state. The same effect is produced.
According to the fifth aspect of the present invention, in the second bank that is in the cylinder deactivation state during the partial cylinder operation of the internal combustion engine, the vibration caused by the combustion is reduced as compared with when it is in the operation state. Since the vibration of the engine can be reduced, the durability of the engine cover can be improved.

1 is a schematic view of a main part of an internal combustion engine to which the present invention is applied, and a part of an intake chamber and an engine cover are cross-sectional views taken along the line II of FIG. 2, and a part of the internal combustion engine is schematically shown Has been. FIG. 2 is a perspective view of an intake cover and an engine cover of the intake chamber of FIG. 1. FIG. 2 is a top plan view of an intake cover and an engine cover of the intake chamber of FIG. 1. FIG. 4 is a side view of a second intake cover of the intake chamber as viewed in the direction of arrow IV in FIG. 1. It is a side view of the engine cover in the arrow V direction of FIG.

Hereinafter, embodiments of the present invention will be described with reference to FIGS.
Referring to FIG. 1, an internal combustion engine E to which the present invention is applied is a V-type internal combustion engine as a multi-cylinder internal combustion engine mounted on a vehicle, and in an engine room formed by a vehicle body cover at the front portion of the vehicle. Placed in.
The internal combustion engine E includes an engine body Ea including a pair of banks, a first bank B1 and a second bank B2, and a combustion chamber connected to the pair of banks B1 and B2 and provided in each of the banks B1 and B2. First and second intake devices N1 and N2 for guiding intake air to 6a and 6b, an engine cover 50 for covering the upper ends of the first and second intake devices N1 and N2 from above in the engine room, and an engine body Ea A crankshaft (not shown in the figure, hereinafter simply referred to as “crankshaft”) and a control device 40 are supported.

The engine body Ea is arranged so as to constitute a pair of cylinder portions 2 and 3 and has a plurality of cylinders 2a and 3a integrally formed by integral molding, and a first cylinder block 1 in the cylinder block 1 , A pair of cylinder heads 4a and 4b respectively coupled to the upper ends of the second cylinder parts 2 and 3, and a pair of head covers 5a and 5b respectively coupled to the upper ends of the pair of cylinder heads 4a and 4b. And an oil pan (not shown) coupled to the lower end of the cylinder block 11.
The lower part of the cylinder block 1 and the oil pan constitute a crankcase forming a crank chamber in which a crankshaft as an output shaft of the internal combustion engine E is disposed, and the crankshaft having a rotation center line is connected to the crankshaft via a main bearing. The crankcase is rotatably supported.

In the embodiment, when the rotation center line of the crankshaft is included in the horizontal plane, the vertical direction is viewed from the axis direction A1 (see FIGS. 3 to 5) which is a direction parallel to the rotation center line. It is assumed that the bisector of the angle formed by the cylinder axes L1 and L2 of the cylinders 2a and 3a of both banks B1 and B2 extends, and in the illustrated example, substantially coincides with the vertical direction. Further, when a plane including the rotation center line and parallel to the vertical direction is defined as the central plane H1, the direction orthogonal to the central plane H1 is defined as the orthogonal direction A2, and the plan view means viewing from the vertical direction. .
In addition, in the specification, the expression “almost” includes the case where there is no modifier “almost” and does not exactly match the case where there is no modifier “almost”, but “almost”. This means a range in which there is no significant difference in action and effect compared to the case where there is no modifier.

Each cylinder part 2 and 3 is comprised by one cylinder, or is comprised by the cylinder row | line | column which consists of a some cylinder. Accordingly, the first bank B1 has one or more first cylinders 2a, and the second bank B2 has one or more second cylinders 3a. In the cylinder rows of the banks B1 and B2, the plurality of cylinders 2a and 3a are arranged in a cylinder arrangement direction parallel to the axial direction A1.
In this embodiment, both cylinder parts 2 and 3 have the same number of cylinders 2a and 3a, respectively. Each of the pair of banks B1 and B2 includes the cylinder portions 2 and 3, cylinder heads 4a and 4b, and head covers 5a and 5b.
Further, in a state where the internal combustion engine E is mounted on the vehicle, the rotation center line L is parallel to the vehicle front-rear direction, and in a pair of banks B1 and B2 forming a V shape when viewed from the axial direction A1, The first bank B1 is a right bank, and the second bank B2 is a left bank.

The internal combustion engine E circulates both the intake devices N1 and N2 in addition to the first and second intake devices N1 and N2 connected to the cylinder heads 4a and 4b of both banks B1 and B2, respectively. A plurality of fuel injection valves 7a and 7b serving as an air-fuel mixture forming device that supplies fuel mixed with the intake air sucked into 6b to form an air-fuel mixture, and a first and a second connected to both cylinder heads 4a and 4b, respectively. Second exhaust devices 8a and 8b are provided.
The intake devices N1 and N2 form intake passages P1 and P2 for introducing outside air to the combustion chambers 6a and 6b provided in the corresponding banks B1 and B2, and the exhaust devices 8a and 8b are located in the combustion chambers 6a and 6b. An exhaust passage is formed that guides the combustion gas as exhaust gas to the outside of the internal combustion engine E.

In each of the banks B1 and B2, pistons 10a and 10b that are fitted in the cylinders 2a and 3a so as to be able to reciprocate are provided, and a combustion chamber formed by the cylinders 2a and 3a, the cylinder heads 4a and 4b, and the pistons 10a and 10b. 6a and 6b are provided for each of the cylinders 2a and 3a, and the cylinder heads 4a and 4b further include intake ports 11a and 11b for introducing intake air flowing through the intake devices N1 and N2 to the combustion chambers 6a and 6b, and an exhaust device. In order to ignite an air-fuel mixture of exhaust ports 12a and 12b for introducing exhaust gas from the combustion chambers 6a and 6b to 8a and 8b, and intake air guided by the intake devices N1 and N2 and fuel from the fuel injection valves 7a and 7b. The intake ports 11a, 11b and the exhaust ports 12a, 12b are respectively driven by spark plugs 13a, 13b facing the combustion chambers 6a, 6b and valve gears 16a, 16b having cam shafts. It closes the intake valves 14a, 14b and exhaust valves 15a, and a 15b, each cylinder 2a, are provided corresponding to 3a.
The pistons 10a and 10b are driven by the pressure of the combustion gas generated by the combustion of the air-fuel mixture in the combustion chambers 6a and 6b to reciprocate, and rotate the crankshaft via the connecting rod.

Each intake device N1, N2 connected to the cylinder heads 4a, 4b in the bank space S1 formed between the banks B1, B2 in the orthogonal direction A2 has an air cleaner and takes in outside air as intake air. 20, 30, intake chambers 21, 31 connected to the downstream ends of the air intake devices 20, 30, and throttle valves 22 a, 32 a for controlling the intake air amount that is the flow rate of the intake air, and the intake chamber 21, Throttle devices 22, 32 connected to the downstream end of 31 and intake connection devices 23, 33 connected to the throttle devices 22, 32 at the upstream end and connected to the cylinder heads 4a, 4b at the downstream end.
The intake passages P1 and P2 are formed by the intake chambers 21 and 31, the throttle devices 22 and 32, and the intake connection devices 23 and 33, and are independent passages.
In the air intake devices 20 and 30, some components such as the air cleaner may be shared by both the air intake devices N1 and N2.

The throttle devices 22 and 32 are arranged in the axial direction A1 (see FIG. 3), and a plurality of throttle bodies 22b and 32b each having throttle valves 22a and 32a are integrated. The intake air connection devices 23 and 33 are formed by integrating a plurality of injector bases 23b and 33b corresponding to the throttle bodies 22b and 32b. Throttle bodies 22b and 32b and injector bases 23b and 33b are made of light metal.
At least the same number of fuel injection valves 7a and 7b as the throttle bodies 22b and 32b are mounted on the injector bases 23b and 33b, respectively. However, as another example, they may be mounted on the cylinder heads 4a and 4b.
As another example, when the throttle devices 22 and 32 are constituted by only one throttle body having one throttle valve for each of the banks B1 and B2, the intake air connection devices 23 and 33 are constituted by intake manifolds.

The control device 40 includes an operating state detecting unit 42 that detects an operating state including the engine operating state of the internal combustion engine E and the traveling state of the vehicle, and the fuel injection valve 7a based on the operating state detected by the operating state detecting unit 42. 7b, electric motors 43a and 43b as actuators for opening and closing the throttle valves 22a and 32a, and a controller 41 for controlling the ignition devices 44a and 44b for controlling the ignition timing of the spark plugs 13a and 13b.
The operating state detection means 42 includes a rotation speed detection means 42a that detects the engine rotation speed, an air amount detection means 42b that is provided in the intake devices N1 and N2, and detects the intake air amount that is the flow rate of the intake air, and a throttle valve It comprises an accelerator operation amount detection means 42c for determining the opening degree of 22a, 32a and other detection means 42d.

  The internal combustion engine E is controlled by the control unit 41 of the control device 40 so that a part of the cylinders 3a, 3a of the internal combustion engine E is in an operating state in which combustion in the combustion chamber 6b is performed. , And cylinder resting means 45 for switching to a cylinder resting state in which combustion in the combustion chamber 6b is not performed. The cylinders 2a constituting the first bank B1 are service cylinders C1 that are always in operation during the operation of the internal combustion engine E, and the cylinders 3a constituting the second bank B2 are operated by the cylinder deactivation means 45. In addition, the cylinder C2 can be deactivated to be switched to a cylinder resting state.

The cylinder deactivation means 45 includes a fuel injection valve 7b, an ignition device 44b, and a valve deactivation mechanism 46. The valve deactivation mechanism 46 suspends the opening / closing operation of the intake valve 14b and the exhaust valve 15b corresponding to the deactivatable cylinder C2 and keeps the valve closed (that is, the intake valve 14b and the exhaust valve 15b are respectively in the valve deactivation state). ) Is a mechanism known per se, and constitutes a part of the valve gear 16b provided in the second bank B2.
The intake valve 14b and the exhaust valve 15b corresponding to the restable cylinder C2 are opened / closed in synchronism with the rotation of the crankshaft at a predetermined opening / closing timing by the camshaft of the valve gear 16b when the valve resting mechanism 46 is not operated. When the valve pause mechanism 46 is operated, the valve is paused without being opened and closed by the cam shaft.

  For this reason, in the cylinder C2 which can be stopped in the operating state, the fuel is supplied and ignited by the fuel injection valve 7b and the ignition device 44b by the control device 40, and the valve suspension mechanism 46 is inactivated, so that the service cylinder C12a , 3a is combusted, and in the resting cylinder C2 in the resting cylinder state, the control device 40 stops the fuel supply and ignition by the fuel injection valve 7b and the ignition device 44b and the valve resting mechanism 46 is operated. In this state, the intake valve 14b and the exhaust valve 15b are in a valve pause state, so that combustion is not performed.

The operation mode of the internal combustion engine E is such that all cylinders 2a in the first bank B1 and all cylinders 3a in the second bank B2 are in an operating state by the cylinder deactivation means 45 controlled by the control device 40 according to the operation state. A first operation mode that is an all-cylinder operation, and a second partial operation that is a partial cylinder operation in which all cylinders 2a in the first bank B1 are in an operating state and all cylinders 3a in a second bank B2 are in an inactive state. The operation mode is switched according to the operation state.
For example, the internal combustion engine E is operated in the first operation mode in a first operation region including an output-oriented operation region such as an acceleration operation region of the internal combustion engine E (including when the vehicle starts) and a high load operation region, The internal combustion engine E is operated in the second operation mode in a second operation region including a fuel efficiency-oriented operation region such as a low-load operation region (including when the vehicle is driven at a constant speed).
Thus, the internal combustion engine E is a variable cylinder internal combustion engine in which the number of operating cylinders 2a and 3a is controlled according to the operating state.

  Further, when the valve deactivation mechanism 46 is operated, the intake air flow in the intake passage P2 (and hence the intake chamber 31) of the second intake device N2 is blocked in order to keep the intake valve 14b and the exhaust valve 15b closed. Therefore, the valve pause mechanism 46 shuts off the intake air flow so that the intake air does not flow into the combustion chamber 6b by interrupting the intake air flow in the intake passage P2 when the second bank B2 is in the idle state. It is also a mechanism.

1 to 3, intake chambers 21 and 31 and an engine cover 50 for improving the design of the internal combustion engine E constitute an upper end portion of the internal combustion engine E mounted on a vehicle, and the engine It is exposed upward in the room.
The intake chambers 21 and 31 form intake expansion chambers P1a and P2a that are part of the intake passages P1 and P2. The intake expansion chambers P1a and P2a are intake air collection chambers in which throttle passages P1b and P2b (part of the intake passages P1 and P2) formed by the throttle bodies 22b and 32b are opened, and the intake passage P1. , P2 is a passage portion having the largest passage area.

Each of the intake chambers 21, 31 includes an intake case 26, 27 that is a main body formed of a synthetic resin, and an intake cover 60, 70 that is formed of a light metal as a metal and is detachably coupled to the intake case 26, 27. Is provided. Further, the engine cover 50 that is disposed across the intake covers 60, 70 in the orthogonal direction A2 and covers at least a part of each intake cover 60, 70 is formed of synthetic resin.
Therefore, the intake cases 26 and 27 and the engine cover 50 are formed of a forming material having a thermal conductivity smaller than that of the forming materials of the intake covers 60 and 70, the throttle bodies 22b and 32b, and the intake connecting devices 23 and 33. ing. In another example, the intake covers 60 and 70 may be made of synthetic resin.

The intake covers 60 and 70 are fastened to the opening edges 26a and 27a of the intake cases 26 and 27 by bolts 95 (see FIG. 1) as connecting means at the connecting portions 62 and 72 of the annular peripheral portions 61 and 71. To be fixed. The annular opening edges 26a and 27a form opening ports 26c and 27c (see FIG. 1) that open upward and are closed by the intake covers 60 and 70.
In each of the intake covers 60 and 70 having a substantially rectangular shape whose longitudinal direction is substantially parallel to the axial direction A1 in plan view, the plurality of coupling portions 62 and 72 are spaced along the peripheral edge portions 61 and 71. Provided. The plurality of coupling portions 62; 72 are provided at first and second side edge portions 61a, 61b; 71a, 71b along the axial direction A1 at the peripheral edge portions 61; 71, respectively, at intervals in the axial direction A1. Are arranged one by one. The first side edges 61a and 71a are covered by the engine cover 50 from above and are side edges near the center plane H1 in the orthogonal direction A2, and the second side edges 61b and 71b are covered by the engine cover 50 from above. It is not covered and is an edge on the side opposite to the first side edges 61a and 71a in the orthogonal direction A2.
On the upper surface of each intake cover 60, 70, recesses 63, 73 that accommodate later-described projecting portions 52, 53 that are a part of the engine cover 50 are provided to be recessed toward the intake expansion chambers P 1 a, P 2 a.

The two intake chambers 21 and 31 are separated in the orthogonal direction A2, and a gap S2 in the orthogonal direction A2 is formed between the two intake chambers 21 and 31, and the gap S2 is at a position intersecting the central plane H1. .
The engine cover 50 covers substantially the entire air gap S2 and the portions near the air gap S2 (or the central plane H1) of the air intake covers 60 and 70 in the orthogonal direction A2 from above, the air intake devices N1, N2, Further, in the internal combustion engine E, only the second intake cover 70 which is one of the first and second intake covers 60 and 70 is fixed, and the first intake cover 60 which is the other intake cover is fixed to the first intake cover 60 which is the other intake cover. Is not fixed.

The engine cover 50 has a predetermined number of clips 91 to 93 as one or more, preferably a plurality of clips 91 to 93 (refer to FIGS. 1 and 3 to 5). Is detachable.
In the intake chambers 21 and 31, since the intake covers 60 and 70 covered with the engine cover 50 are separate members from the intake cases 26 and 27, only the intake covers 60 and 70 are changed to intake covers of other shapes. Thus, the volume of the intake expansion chambers P1a and P2a involved in engine performance can be easily changed, and even when the engine cover 50 is changed, it is easy to change only the intake covers 60 and 70, and Can be handled at low cost.

1 to 4, the second intake cover 70 is provided at an interval in the axial direction A1 at the first side edge 71a facing the first intake cover 60 or the central plane H1 in the orthogonal direction A2. Further, it has three fixing portions 81 to 83 equal to the predetermined number. The fixing portions 81 to 83 include two end fixing portions 81 and 83 located at both ends in the axial direction A1, and one or more, here, intermediate positions between the both end fixing portions 81 and 83 in the axial direction A1. One intermediate fixing portion 82 is included.
The fixing portions 81 to 83 that are located above the coupling portions 72 (see FIG. 4) and are integrally formed with the intake cover 70 are protruding portions that protrude in the orthogonal direction A2 from the side edge portion 71a. Retaining holes 81a to 83a each having a through hole in which the clips 91 to 93 are inserted and retained are provided. The holding holes 81a to 83a that define the fixing positions of the clips 91 to 93 in each of the fixing portions 81 to 83 are at positions that intersect the center plane H1 or the fixing position plane H2 that is a plane parallel to the center plane H1. In the illustrated example, the center plane H1 and the fixed position plane H2 coincide.

Referring to FIGS. 1 to 3 and 5, the engine cover 50 formed substantially symmetrically with the fixed position plane H2 as a symmetry plane extends in the axial direction A1 and intersects the fixed position plane H2. And first and second projecting portions 52 and 53 projecting from the main body 51 in the orthogonal direction A2, and a contact portion 54 that contacts the top surfaces of the first and second intake covers 60 and 70 in a float state. .
The main body 51 includes clips 91 and 93 that are locked and fixed to the predetermined number of fixing portions 81 and 83, respectively, and one strip extending along the axial direction A1 at a position that intersects the fixing position plane H2. Reinforcing ribs 59 are provided. The contact portion 54 is provided at the distal end side portions 52b and 53b, which are portions near the distal end portions 52a and 53a that are located in the direction away from the fixed position plane H2 in each of the projecting portions 52 and 53.
The clips 91 to 93, the contact portion 54, and the rib 59 are provided on the lower surface (or the back surface) that is the surface on the side where the two intake covers 60 and 70 are positioned in the vertical direction. The clip 91 is provided integrally with the main body 51, the clip 93 is provided integrally with the rib 59, and the clip 92 is a separate member from the engine cover 50 (in FIG. It is indicated by a dotted line.) The clip 92 passes through the main body 51 and is fixed to the fixing portion 82.

Therefore, the engine cover 50 is fixed to the second intake cover 70 by the fixing portions 81 to 83 and supported in the float state at the contact portion 54, while being fixed to the first intake cover 60. Without being supported in a float state.
Here, the contact portion 54 is in contact with the float state when the relative displacement between the intake covers 60 and 70 and the engine cover 50 occurs, the contact portion 54 is restrained by the intake covers 60 and 70. It means that it can move on each intake cover 60, 70 while maintaining the contact state with each intake cover 60, 70. Further, the engine cover 50 being supported by the intake covers 60, 70 in the float state means that the engine cover 50 is in contact with the intake covers 60, 70 in the float state, so that the engine cover 50 is in contact with the intake covers 60, 70. It means that it is supported by.

  The contact portion 54 includes a first contact portion 55 that contacts the first intake cover 60 and a second contact portion 56 that contacts the second intake cover 70. Each of the first and second contact portions 55 and 56 disposed substantially symmetrically with respect to the fixed position plane H2 includes one or more, here, one elongated first contact body 57 and one or more, here, a plurality of contacts. The second contact body 58. The first contact body 57 provided in the main body 51 is disposed in a state of being elongated in a direction inclined with respect to the fixed position plane H2 in a plan view. The second contact body 58 is provided on the tip side portions 52b and 53b of the first and second overhang portions 52 and 53. All the second contact bodies 58 are arranged on a straight line substantially parallel to the fixed position plane H2 in plan view. Here, the second contact body 58 provided on the tip side portion 52b of the first overhang portion 52 constitutes the first contact body group 58a, and the second contact body 58 provided on the tip side portion 53b of the second overhang portion 53 is provided. The contact body 58 constitutes a second contact body group 58b.

Each of the contact bodies 57 and 58 is formed of an elastic material having rubber-like elasticity, for example, a buffer material made of rubber, and is fixed to the intake covers 60 and 70 by a fixing means such as an adhesive. Therefore, in the contact part 54, the contact part with the intake covers 60 and 70 is configured by a buffer part that buffers contact with the intake covers 60 and 70 due to vibration.
All the contact bodies 57, 58 have an axial line between the both end fixing portions 81, 82 in the axial direction A1, and therefore within the axial direction range (or longitudinal range) defined by the both end fixing portions 81, 82. It arrange | positions at intervals in the direction A1, and is arrange | positioned on both sides of the space | gap S2 in orthogonal direction A2 by planar view.

  Therefore, even if relative displacement occurs between the first intake cover 60 and the second intake cover 70 due to thermal expansion or vibration, the first intake cover 60 is float-supported without being fixed to the first intake cover 60. The engine cover 50 has a first intake air with respect to the first intake cover 60 except that the downward movement is restrained by contact with the first and second intake covers 60, 70 at the contact portion 54. The second intake cover 70 can be moved freely with almost no restraint by the cover 60, and is fixed to the second intake cover 60 with fixing portions 81 to 83, whereby the second intake cover Displaces almost integrally with 70.

  The second intake cover 70 has a pair of side edge portions 71a and 71b with a fixed portion 81 at a side edge portion 71a near the first intake cover 60 and near the central plane H1 (or fixed position plane H2) in the orthogonal direction A2. The engine cover 50 having a shape substantially symmetrical with respect to the fixed position plane H2 is fixed to the fixing portions 81 to 83 at a position intersecting with the fixed position plane H2, The second contact portions 55 and 56 are provided at positions that are substantially plane symmetric with respect to the fixed position plane H2, and the intake covers 60 and 70 are floated at positions where the engine cover 50 is substantially plane symmetric with respect to the fixed position plane H2. The engine cover 50 fixed only to the second intake cover 70 can be stably supported by the pair of intake covers 60, 70.

  Further, the tip side portions 52b and 53b of the first and second projecting portions 52 and 53 of the engine cover 50 are accommodated in recesses 63 and 73 provided on the upper surfaces of the first and second intake covers 60 and 70, respectively. Since the contact portions 55 and 56 are provided on the tip end portions 52b and 53b, the contact portions 55 and 56 are protruded downward from the lower surfaces of the tip end portions 52b and 53b. , 56 can be compactly arranged in the vertical direction with respect to both intake covers 60, 70.

Next, operations and effects of the embodiment configured as described above will be described.
In the internal combustion engine E including the first and second banks B1 and B2, the first and second intake chambers 21 of the first and second intake devices N1 and N2 connected to the first and second banks B1 and B2, respectively. The engine cover 50 is arranged so as to be spaced apart from each other and covers the gap S2 formed between the first and second intake chambers 21 and 31 from above. 2 The engine cover 50 is disposed across the intake covers 60, 70 and is fixed to the second intake chamber 31, which is one of the first intake chamber 21 and the second intake chamber 31, by the intake cover 70. As a result, variations in assembly accuracy of the first and second intake devices N1 and N2 with respect to the first and second banks B1 and B2 and a plurality of devices (for example, the first and second intake devices N1 and N2) Throttle devices 22, 23 and intake air connection devices 23, 33 Even when the positions of the first and second intake chambers 21 and 31 vary due to the variation in assembly accuracy, the first intake air that is the other intake chamber in the first and second intake chambers 21 and 31. The engine cover 50 can be fixed to one intake chamber 31 without being restricted by the position of the chamber 21. As a result, the assembly of the engine cover 50 is facilitated and its assemblability is improved, and the fixing structure with respect to the intake chamber 31 is simplified, and the cost can be reduced.

  The internal combustion engine E operates the first cylinder 2a in the first bank B1 and the second cylinder 3a in the second bank B2 in the operating state, and sets the first cylinder 2a in the operating state and the second cylinder 3a. By providing the cylinder deactivation means 45 for switching the operation mode to the second operation mode to be in the cylinder deactivation state, the first bank B1 and the second bank B2 in the partial cylinder operation in which the second bank B2 is in the cylinder deactivation state. The first and second intake chambers 21 are caused by the difference in thermal expansion between the first and second banks B1 and B2 and the difference in thermal expansion between the first and second intake devices N1 and N2 due to the difference in the heat generation amount of the first and second banks B1 and B2. , 31, even if a displacement occurs, the engine cover 50 is fixed only to the second intake chamber 31, which is one of the first and second intake chambers 21, 31, so that the engine cover 50 is stressed by the displacement. It is Therefore, the durability of the engine cover 50 is improved.

  Since the engine cover 50 is fixed only to the second intake chamber 31, the second bank B <b> 2 that is in a cylinder deactivation state during the partial cylinder operation of the internal combustion engine E is caused by combustion as compared with when it is in an operation state. Since the vibration is reduced, the vibration of the engine cover 50 can be reduced correspondingly, so that the durability of the engine cover 50 can be improved.

Hereinafter, an embodiment in which a part of the configuration of the above-described embodiment is changed will be described with respect to the changed configuration.
In the embodiment, the fixing portion is provided in the first intake cover 60 instead of being provided in the second intake cover 70 in the same form as the embodiment, and the engine cover 50 is provided in the first and second intake chambers 21. , 31 may be fixed only to the first intake chamber 21 as one of the intake chambers.
In this case, the internal combustion engine E has, as the cylinder deactivation means 45, a valve deactivation mechanism 46 serving as an intake flow block mechanism that blocks the flow of intake air in the second intake device N2 when the second bank B2 is in the non-cylinder state. In addition, since the engine cover 50 is fixed only to the first intake chamber 21, the second intake device N2 having the second intake chamber 31 where the intake air flow is blocked is cooled by the flowing intake air. Compared to the first intake device N1 having the first intake chamber 21 having a relatively low temperature, the engine cover 50 is heated to a higher temperature due to heat radiation from the first bank B1 in the operating state, whereas the engine cover 50 has a relatively low first temperature. Since it is fixed only to the intake chamber 21, the thermal influence on the engine cover 50 can be reduced, and its durability can be improved.

The first and second intake chambers may be configured only by the intake case without providing the intake cover. In this case, the engine cover 50 is fixed to the intake case.
The intake air flow blocking mechanism may be an intake air control mechanism including an intake air shielding valve that can close the intake port 11b of the cylinder head 4b of the second intake passage P2 or the second bank B2 formed by the second intake device N2. . In the intake control mechanism, the intake shielding valve is controlled by the control device 40 to close the intake passage P2 or the intake port 11b when the cylinder 3a of the second bank B2 is in the closed state, and the second intake device N2 When the second bank B2 is in an operating state, the intake passage P2 or the intake port 11b is opened to allow the intake air to flow into the combustion chamber 6b. The throttle valve 32a may also serve as the intake shielding valve.
The internal combustion engine may be of a horizontally opposed type including a pair of banks B1 and B2 or a pair of engine blocks opposed in the horizontal direction.
The contact portion 54 may be provided on the engine cover 50 by integral molding, or may be provided on each of the intake covers 60 and 70.
The intake chamber may be connected to the downstream end of the throttle device.
The internal combustion engine is a variable cylinder internal combustion engine having a restable cylinder, but may be an internal combustion engine not having a restable cylinder. In this case, the engine cover 50 may be the first and second intake covers. Only fixed to either 60 or 70.

2a, 3a ... cylinder, 21, 31 ... intake chamber, 26, 27 ... intake case, 45 ... cylinder stop means, 46 ... valve stop mechanism, 50 ... engine cover, 60, 70 ... intake cover, 81-83 ... fixed part ,
E ... Internal combustion engine, B1, B2 ... Bank, N1, N2 ... Intake device, S2 ... Air gap.

Claims (5)

A first bank and a second bank;
A first intake chamber of a first intake device connected to the first bank and a second intake chamber of a second intake device connected to the second bank;
An internal combustion engine comprising: an engine cover disposed between the first intake chamber and the second chamber that are spaced apart from each other;
The internal combustion engine, wherein the engine cover is fixed only to one of the first intake chamber and the second intake chamber. The internal combustion engine of claim 1,
A first operation mode in which the first cylinder of the first bank and the second cylinder of the second bank are in an operating state; and a second mode in which the first cylinder is in an operating state and the second cylinder is in a closed cylinder state. An internal combustion engine comprising: a cylinder deactivation means for switching between operation modes. The internal combustion engine according to claim 2,
The cylinder pause means includes an intake air flow blocking mechanism that blocks the flow of intake air in the second intake device when the cylinder is in the idle state.
The internal combustion engine, wherein the one intake chamber is the first intake chamber. The internal combustion engine according to claim 3,
The internal combustion engine, wherein the intake flow blocking mechanism is a valve pause mechanism that keeps an intake valve and an exhaust valve provided in the second bank in a closed state in the pause state. The internal combustion engine according to claim 2,
The internal combustion engine, wherein the one intake chamber is the second intake chamber.

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