JP6883011B2 - Internal combustion engine for automobiles - Google Patents

Description

The present invention relates to an internal combustion engine mounted on an automobile.

In automobile foot brakes, the stepping force is increased by a brake booster that uses the intake negative pressure, but in recent years, due to the spread of superchargers, etc., the negative pressure of the brake booster cannot be covered by the intake negative pressure alone. In some cases, an electric vacuum pump is installed as an auxiliary vacuum source for the brake booster. As an example, Patent Document 1 discloses that a vacuum pump is attached to a vehicle body frame.

Japanese Unexamined Patent Publication No. 2014-227153

Since the vacuum pump is not an indispensable component of the internal combustion engine, its arrangement location can be arbitrarily set. However, in the configuration of Patent Document 1, when the vacuum pump is driven, its vibration is transmitted to the inside of the vehicle via the vehicle body frame. There is a concern that it may cause discomfort to the occupants.

In particular, since the vacuum pump of the type in which the piston reciprocates has a large vibration, there is a strong concern that the vibration will spread to the inside of the vehicle. Further, in a small vehicle such as a light vehicle, it is difficult to use a large amount of anti-vibration material in order to secure as much space as possible in the vehicle, so it can be said that the problem of vibration due to the drive of the vacuum pump is likely to appear strongly.

Further, in Patent Document 1, since it is necessary to manufacture a special bracket or to process a tap hole in the vehicle body frame, there is a possibility that the cost for mounting increases.

The present invention has been made to improve such a situation.

The invention of the present application specifies a typical example in each claim. Of these, the invention of claim 1 is
"Is disposed in an engine room provided in a front portion of a vehicle body, the front surface of the cylinder block and the cylinder head, a configuration in which a front cover covering a timing chain is overlaid fixed,
The front cover is provided with upper and lower auxiliary boss portions protruding from the overlapping portion with the cylinder block or the cylinder head, and a vacuum pump having a piston that reciprocates in substantially the vertical direction is fixed to the upper and lower auxiliary boss portions. Is there "
It is configured as.
The "upper and lower" specified in claim 1 does not mean only two upper and lower places, but means a plurality of upper and lower places.

The invention of claim 2 is claimed in claim 1.
"The vacuum pump that assists the brake booster is fixed to the rear surface of the upper and lower auxiliary boss portions on the side that overlaps with the cylinder block or the cylinder head."
It is configured as.
The invention of claim 3 embodies claim 2.
"A seal applied to the overlapping surface of the front cover and the cylinder block or the cylinder head at a portion of the rear surface of the auxiliary boss portion of the front cover that is closer to the cylinder block or the cylinder head than the overlapping surface with the vacuum pump. It forms a groove through which the agent can flow. "
It is configured as.

The invention of claim 4 is in any of claims 1 to 3.
"Main boss portions for fixing the front cover to the cylinder block or the cylinder head are arranged on both upper and lower sides of the auxiliary boss portion, and the auxiliary boss portion and the main boss portion are connected by ribs."
It is configured as.

Since an internal combustion engine for an automobile is supported by a vehicle body frame via anti-vibration rubber, even if vibration is generated by driving the vacuum pump, the vibration peculiar to the vacuum pump is not transmitted to the inside of the vehicle. Further, even if vibration is generated by driving the vacuum pump, the vibration of the vacuum pump is usually absorbed by the vibration of the internal combustion engine because the internal combustion engine itself vibrates more than the vacuum pump. In addition, since the front cover has a sturdy structure, the vacuum pump can be firmly fixed, so that the generation of vibration itself can be suppressed.

As a result, the vibration caused by the drive of the vacuum pump is not transmitted to the inside of the vehicle, and it is possible to prevent the occupant from feeling uncomfortable.

Further, there is an advantage that the dead space existing in the peripheral portion of the front cover can be effectively used. In particular, when the vacuum pump is attached to the rear surface of the front cover as in claim 2 , the vacuum pump can be arranged at a position where it does not interfere with the auxiliary drive belt, which is particularly advantageous in terms of effective use of space.

Now, in Patent Document 1, although secure the vacuum pump to the body of the side frame, this is the center of gravity of the car from portrait centerline supposed to shift slightly to the left and right outside, just the stability during cornering However, it may be lowered.

On the other hand, when the vacuum pump is fixed to the rear surface of the front cover as in claim 2 , the vacuum pump is moved to the vertically long center line of the automobile regardless of whether the internal combustion engine is installed horizontally or vertically. Therefore, it is possible to prevent a decrease in stability during turning. If the internal combustion engine is a transverse type, fixing the vacuum pump to the rear surface of the front cover is particularly beneficial because the vacuum pump is closer to the vertical centerline of the vehicle.

A liquid sealant is applied to the overlapping surface of the front cover, the cylinder block, and the cylinder head, but the sealing agent may squeeze out of the overlapping surface after fixing. The vacuum pump is retrofitted after the front cover is fixed to the cylinder block and the cylinder head, but if the sealant is flowing through the auxiliary boss portion, the vacuum pump may be improperly attached.

On the other hand, when the configuration of claim 3 is adopted, even if the sealing agent protrudes to the outside of the polymerization surface, it is possible to prevent the protruding sealing agent from flowing into the concave groove and reaching the auxiliary boss portion, so that the vacuum pump can be used. Can be fixed in an accurate posture without tilt. Further, since the front cover is thin at the concave groove portion, it is possible to absorb the vibration caused by the drive of the vacuum pump at the concave groove portion.

In the invention of claim 1 , the vacuum pump generates vibration in the vertical direction when the piston reciprocates in the substantially vertical direction, but since the auxiliary boss portion is arranged up and down, the vacuum pump is touched as much as possible. It can be firmly fixed in the suppressed state. Therefore, Ru can contribute greatly to the suppression of vibration.

The side portion of the front cover is fixed to the cylinder block and the cylinder head with a large number of bolts. Therefore, a large number of main boss portions for fixing to the cylinder block and the cylinder head are formed on the side portion of the front cover.

Then, although Meinbosu portion has a robust construction to be strongly pressed by bolts, as in claim 4, when connecting the auxiliary boss and Meinbosu section ribs, the site where the vibration of the vacuum pump is spread Since the rigidity is significantly increased, the installation of the vacuum pump can be further strengthened.

Further, in claim 4, since the ribs are located outside the cylinder block and the cylinder head, the area of the portion extending above and below the auxiliary boss portion increases, and the vibration of the vacuum pump can be significantly absorbed. As a result, it is possible to suppress the spread of vibration to the overlapping portion between the front cover and the cylinder block or the cylinder head, and prevent distortion of the sealing surface between the front cover and the cylinder block or the cylinder head.

It is a side view which looked at the embodiment from the side of the intake side. It is a rear view of the front cover as seen from the II-II viewing direction of FIG. It is a separation side view which looked at the front cover and a vacuum pump from the side of the intake side. It is a perspective view seen from the side of the intake side. It is a perspective view seen from the front side. It is a perspective view seen from the front side with the vacuum pump omitted. It is a perspective view seen from the side of the intake side with the vacuum pump omitted.

Next, an embodiment of the present invention will be described with reference to the drawings. The internal combustion engine is arranged in an engine room provided at the front of the automobile, but in the present embodiment, the internal combustion engine is a transverse engine arranged so that the crankshaft is in a long position in the left-right direction of the vehicle body. Is. Further, the relationship between intake and exhaust is front exhaust and rear intake in which the exhaust side surface is located on the front side in the traveling direction with reference to the forward direction of the automobile.

On the other hand, in an internal combustion engine, it is common to refer to the crank axis direction as the front-rear direction in order to specify the direction, the side on which the timing chain is arranged is called the front, and the side on which the mission is arranged is called the back. The cover that covers the timing chain is called the front cover.

This general usage is also used for the direction of the internal combustion engine in this embodiment, but as described above, since the internal combustion engine of the embodiment is placed horizontally, the front-rear direction of the automobile and the front-rear direction of the internal combustion engine are 90. ° It is different. The front-back direction is clearly shown in FIG. The left-right direction is a direction orthogonal to the crank axis and the cylinder bore axis.

(1). Overview The internal combustion engine of the present embodiment has the same basic aspects as before, and as shown in FIG. 1, the cylinder block 1 and the cylinder head 2 fixed to the upper surface thereof, and the cylinder block 1 and the cylinder. It is provided with a front cover 3 fixed to the front surface of the head 2. An oil pan 4 is fixed to the lower surface of the cylinder block 1, while a head cover (not shown) is fixed to the upper surface of the cylinder head 2. The lower portion of the front cover 3 is also fixed to the front surface of the oil pan 4. The main part of the engine body is composed of the cylinder block 1, the cylinder head 2, the front cover 3, and the head cover.

The cylinder head 2 of the present embodiment has a laminated system of the upper member 2a and the lower member 2b, and the intake manifold 5 is fixed to the intake side surface of the lower member 2b. The upper surface of the cylinder head 2 is indicated by reference numeral 6, the boundary line between the upper and lower members 2a and 2b constituting the cylinder head 2 is indicated by reference numeral 7, and the boundary line between the cylinder block 1 and the cylinder head 2 is indicated by reference numeral 8.

As can be understood from the form of the intake manifold 5, the internal combustion engine of the present embodiment has four cylinders. The member indicated by reference numeral 9 in the upper right portion of FIG. 1 is a bracket for supporting the EGR valve, and the member indicated by reference numeral 10 in the lower right portion of FIG. 1 is an oil filter.

As shown in FIG. 2, a window hole 11 for attaching a VVB device for an intake valve is opened in a portion of the upper portion of the front cover 3 closer to the intake side surface. Although not dared to explain, the front cover 3 has a shallow shell-like shape that opens toward the cylinder block 1 and the cylinder head 2. Therefore, the cylinder block 1 and the left and right longitudinal sides of the front cover 3 are provided with the cylinder block 1 and the front cover 3. Front and rear side walls 12a and 12b that overlap with the cylinder head 2 are formed, and main boss portions 13 for fixing the side walls 12a and 12b with bolts are formed on the side walls 12a and 12b.

(2). Vacuum pump Next, the mounting structure of the vacuum pump 15 will be described with reference to other figures. As shown in FIG. 1, the vacuum pump 15 is arranged on the rear side and the front side of the cylinder block 1. As can be easily understood from FIGS. 4 and 5, the vacuum pump 15 has a drum portion 16 in a substantially horizontal posture and a cylinder portion 17 projecting substantially upward from the drum portion 16. While the electric motor and the crank mechanism portion are built in, the cylinder portion 17 has a built-in piston that reciprocates by the crank mechanism. Although not shown, the cylinder portion 17 and the brake booster are connected by a hose (pipeline).

As is clearly shown in FIG. 1, the drum portion 16 has a posture in which its axis extends long in the same front-rear direction as the crank axis direction, and is arranged so as to straddle both the cylinder block 1 and the front cover 3. ..

Then, for example, as shown by the alternate long and short dash line in FIG. 2, the upper and lower bracket portions 18 are projected from the portion of the drum portion 16 closer to the cylinder portion 17, while being clearly shown in FIGS. 2, 6 and 7. The upper and lower auxiliary boss portions 19 are projected forward on the portion of the front side wall 12a of the front cover 3 that overlaps with the cylinder block 1, and the bracket portion 18 is overlapped on the rear surface of the auxiliary boss portion 19, and both are attached to the auxiliary boss. It is fastened with a bolt 20 inserted through the portion 19. Therefore, the bracket portion 18 is provided with a tap hole into which the bolt 20 is screwed.

As shown in FIGS. 2, 6 and 7, main boss portions 13 are arranged on both upper and lower sides of the auxiliary boss portion 19, and the auxiliary boss portion 19 and the upper and lower main boss portions 13 are ribs 21 having a substantially triangular shape. It is connected as one through. Therefore, on the front cover 3, two upper and lower overhanging portions 22 having a triangular (or chevron-shaped) front view with the auxiliary boss portion 19 at the apex are projected outside the cylinder block 1.

Then, as clearly shown in FIGS. 2 and 7, the auxiliary boss portion 19 and the front side wall 12a are separated from each other in the portion between the cylinder block 1 and the auxiliary boss portion 19 in the overhanging portion 22 so as to be vertically elongated. The concave groove 23 is formed. The depth of the groove 23 is several mm.

(3). Summary In the above configuration, the vacuum pump 15 is attached to the front cover 3 that constitutes the engine body. Therefore, even if vibration is generated by driving the vacuum pump 15, the vibration is transmitted through the vehicle body frame. It does not spread inside the car. Therefore, the vibration caused by the drive of the vacuum pump 15 does not give a sense of discomfort to the occupants (since the vibration of the internal combustion engine is larger than the vibration of the vacuum pump 15 in the first place, the vibration of the vacuum pump 15 is the internal combustion engine. It can be said that it is absorbed by the vibration of the vehicle and does not spread to the inside of the automobile as an independent vibration.)

Further, since the front side of the intake manifold 5 is a kind of dead space, the vacuum pump 15 can be arranged by effectively utilizing the dead space. Therefore, it can contribute to the effective use of the space in the engine room. An auxiliary drive belt is arranged on the front surface of the front cover 3, but since there is a certain distance between the auxiliary drive belt and the front surface of the front cover 3, a vacuum is used as in the present embodiment. If a part of the pump 15 is arranged so as to straddle the front cover 3 in the rear view, there is an advantage that the vacuum pump 15 can effectively use the space without interfering with the intake manifold 4 and the auxiliary drive belt.

When assembling the internal combustion engine, a liquid sealant is applied to the overlapping surfaces of the side walls 12a and 12b of the front cover 3 and the cylinder block 1 and the cylinder head 2, and the front cover 3 is attached to the cylinder block 1 and the cylinder block 1 with the main bolt 24. When fastened to the cylinder head 2, a part of the applied seal may protrude to the outside. Therefore, if the protruding sealant reaches the auxiliary boss portion 19, the adhesion between the bracket portion 18 of the vacuum pump 15 and the auxiliary boss portion 19 is hindered, and there is a concern that the mounting may be defective.

On the other hand, when the vertically elongated concave groove 23 is formed between the front side wall 12a and the auxiliary boss portion 19 as in the present embodiment, even if the sealing agent protrudes to the outside of the front side wall 12a, the protruding seal. agent because never reach the auxiliary boss 19 stopped by a recessed groove 23, it is possible to mount the vacuum pump 15 accurately.

Although it is possible to project the weir plate as a method of stopping the protruding sealant, it is not realistic to provide the weir plate because the end face of the front cover 3 is finished by milling. Further, forming the concave groove 23 is advantageous in terms of fuel consumption because the weight increase of the front cover 3 can be suppressed.

As shown in FIG. 2, in the vacuum pump 15, the cylinder portion 17 is in a substantially vertically long posture. Therefore, the built-in piston reciprocates substantially in the vertical direction. Then, a reciprocating load that attempts to swing the vacuum pump 15 in the vertical direction acts on the vacuum pump 15, and this load is a moment that attempts to rotate the vacuum pump 15 in the vertical direction around the auxiliary boss portion 19. become. Therefore, if the auxiliary boss portions 19 for fixing the vacuum pump 15 are arranged side by side, there is a concern that a large moment acts on the mounting portion and the mounting strength decreases during use. ..

On the other hand, in the present embodiment, since the two auxiliary boss portions 19 are arranged in the vertical direction, a large moment does not act on the auxiliary boss portion 19 and the bracket portion 18, so that the bolt 20 and the bracket A large load is not applied to the unit 18. Therefore, the problem of strength reduction does not occur.

Further, in the present embodiment, since the auxiliary boss portion 19 and the main boss portion 13 are connected by the rib 21, a triangular (mountain-shaped) overhanging portion 22 is formed at the apex of the auxiliary boss portion 19, so that the vacuum pump 15 The rigidity of the part where is fixed is significantly higher. In this respect as well, the mounting strength of the vacuum pump 15 can be improved.

Further, even if the vacuum pump 15 vibrates, the stress due to the vibration is dispersed in the overhanging portion 22, so that the stress generated in the overhanging portion 22 can be remarkably reduced. Therefore, it is possible to prevent that distortion occurs in the sealing surface between the front wall 12a and the cylinder block 1 of the front cover 3. The ribs 21 can be provided only above or below the auxiliary boss portion 19, but if they are provided up and down as in the present embodiment, the rigidity of the overhanging portion 22 becomes remarkably high, which is preferable. is there.

When the vacuum pump 15 is arranged on the intake side of the engine body as in the present embodiment, it is possible to prevent adverse effects due to heat and contribute to ensuring safety. Further, since the vacuum pump 15 is located behind the front surface of the intake manifold 5, the intake manifold 5 acts as a cover in the event of a collision, and it is possible to prevent the vacuum pump 15 from being impacted. In this respect as well, safety can be ensured.

Although the embodiments of the present invention have been described above, the present invention can be embodied in various ways other than the illustrated embodiments.

The invention of the present application can be embodied in an internal combustion engine for automobiles. Therefore, it can be used industrially.

1 Cylinder block 2 Cylinder head 3 Front cover 5 Intake manifold 12a, 12b Side wall of front cover 13 Main boss part 15 Vacuum pump 16 Drum part 17 Cylinder part 18 Bracket part 19 Auxiliary boss part 20 Bolt for fastening vacuum pump 21 Rib 22 Overhang 23 concave groove 24 main bolt

Claims (4)

It is arranged in the engine room provided at the front of the vehicle body, and has a configuration in which a front cover covering the timing chain is overlapped and fixed on the front of the cylinder block and the cylinder head.
The front cover is provided with upper and lower auxiliary boss portions protruding from the overlapping portion with the cylinder block or the cylinder head, and a vacuum pump having a piston that reciprocates in substantially the vertical direction is fixed to the upper and lower auxiliary boss portions. Yes,
Internal combustion engine for automobiles. The vacuum pump that assists the brake booster is fixed to the rear surface of the upper and lower auxiliary boss portions on the side that overlaps with the cylinder block or the cylinder head.
The internal combustion engine for automobiles according to claim 1. A sealant applied to the overlapping surface of the front cover and the cylinder block or the cylinder head at a portion of the rear surface of the auxiliary boss portion of the front cover that is closer to the cylinder block or the cylinder head than the overlapping surface with the vacuum pump. Forming a groove through which
The internal combustion engine for automobiles according to claim 2. Main boss portions for fixing the front cover to the cylinder block or the cylinder head are arranged on both upper and lower sides of the auxiliary boss portion, and the auxiliary boss portion and the main boss portion are connected by ribs.
The internal combustion engine for an automobile according to any one of claims 1 to 3.

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