JPH06221223A - Oil pan structure of engine - Google Patents

Abstract

PURPOSE:To suppress sufficiently PPB of lateral bending mode and longitudinal bending mode by improving the structure of an oil pan which is installed on the bottom surface part of the engine main body, and provided with a fastening flange fastened to a transmission together with a fastening part for the transmission of an engine main body. CONSTITUTION:An oil pan structure is provied with a space part 4 formed on the center part bottom surface of the side bottom part a flange 2 for fastening an oil pan A to be used for arranging a starter (a) an expansion part 5 provided on the both side parts of the side bottom part of the fastening flange 2 and expanding downward from a center part so as to enclose the both sides of the space part 4 and an opening part 6 provided on the center part of the fastening flange 2 for opening the space part 4 toward a transmission C. The transmission C side end part of the expansion part 5 is connected integratedly to the fastening flange 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine oil pan structure for an automobile, and more particularly to a measure for improving the joint rigidity between an engine body and a transmission.

[0002]

2. Description of the Related Art An F engine with its engine placed horizontally on the front side
In a power train of an F-structured automobile, as shown in FIG. 6, an output shaft (not shown) of a differential gear d or a transmission b.
Since such heavy objects are laterally offset from the center line of the engine, as shown by the phantom line in the figure, lateral bending using the joint portion c between the engine body a and the transmission b as a node. There is a drawback that PPB (power plant bending) of the mode is likely to occur. Therefore, when PPB occurs, the bending vibration having the joint portion c as a node is likely to resonate with the frequency component of the fundamental order during engine operation, which causes noise such as muffled noise in the vehicle. For this purpose, in order to improve the rigidity of the coupling portion c, a fastening portion of the engine body a to the transmission b and a transmission b of an oil pan (not shown) attached to the lower surface portion of the engine body a are provided. The fastening flanges to be fastened are both substantially semicircular, and the engine body a and the oil pan are in the shape of a cone block and fastened to the transmission b.

By the way, in practice, since the starter must be arranged on the circumference of the ring gear attached to the flywheel or the drive plate, the starter is installed at the fastening portion of the engine body a, for example, on the air supply side. Since a recess for installing the starter is formed in the above, only the exhaust side where the starter is not installed is formed in a cone block shape, and the above cone block structure is not complete. Absent.

Therefore, in the prior art, for example, the actual Kaihei 2-46 is used.
As disclosed in Japanese Patent No. 048, the fastening portion of the engine main body is reinforced and integrated with the starter housing in the starter installation recess.

[0005]

However, in the above-mentioned conventional example, since the installation position of the starter remains laterally offset from the engine center line, the situation in which the starter promotes the PPB in the lateral bending mode does not occur. There is a problem that it is not solved yet.

Also, regarding the fastening portion of the engine body,
Even though it is reinforced, it is difficult to obtain uniform rigidity, and therefore it must be said that it is insufficient to suppress PPB.

The present invention has been made in view of the above points, and an object thereof is to improve the structure of the oil pan so that the starter can be arranged right below the center line of the engine. And to make it possible to sufficiently suppress PPB in the longitudinal bending mode.

[0008]

In order to achieve the above object, in the present invention, an opening is provided at the center of the fastening flange of the oil pan, and the starter rotatably drives the ring gear through this opening.

Specifically, according to the first aspect of the invention, there is provided an oil pan which is attached to a lower surface of an engine body and has a fastening flange for fastening to the transmission together with a fastening portion for the transmission of the engine body. It is a premise.

Then, a space is formed on the lower surface of the central portion of the bottom portion of the oil pan on the side of the fastening flange. Swelling portions that swell downward from the central portion are provided on both sides of the bottom portion so as to surround both sides of the space portion. An opening for opening the space toward the transmission is provided at the center of the fastening flange of the oil pan. Then, the transmission side end of the bulge is integrally connected to the fastening flange.

According to a second aspect of the present invention, in the above-mentioned first aspect, the starter is arranged in a space, and the starter arranged in the space passes through an opening to flywheel or drive. Engage with the ring gear attached to the plate.

[0012] In the invention of claim 3, the above-mentioned claim 1 or 2
In the invention described above, the fastening flange is formed in a substantially semicircular shape, and is formed into a cone block shape together with the substantially semicircular fastening portion of the engine body so as to be fastened to the transmission.

According to a fourth aspect of the present invention, in the above-mentioned first to third aspects, the starter is attached to the fastening flange, and the attachment rigidity of the starter causes the starter to function as a dynamic damper for a longitudinal bending mode of power plant bending. To do.

According to a fifth aspect of the present invention, in the above first to fourth aspects, the bulging portion of the oil pan is communicated with the oil sump portion via the communication portion. Then, a check valve that allows only the outflow of oil from the bulge portion side to the oil sump portion side is arranged in this communication portion.

[0015]

With the above construction, in the invention of claim 1, a space in which the bulging portion bulging downward from the central portion of the fastening flange side bottom portion of the oil pan is formed in the lower central portion of the bottom portion of the oil pan. Since the transmission side end of the bulging portion is integrally connected to the fastening flange, the bulging portion is effective for ensuring vertical bending rigidity and torsional strength of the power plant. Form ribs with a box-shaped cross section.

According to the second aspect of the invention, the starter is installed in the space, and through the opening located at the center of the fastening flange of the oil pan, between the engine side fastening section and the transmission side fastening section, Engages a ring gear mounted on the flywheel or drive plate. In this state, since the starter is located right below the engine center line, it is possible to avoid the situation where the starter promotes the PPB in the lateral bending mode. Further, by changing the installation position of the starter, the conventional starter installation recess is not required in the fastening portion of the engine body, and the rigidity can be easily made uniform.

According to the third aspect of the present invention, the fastening flange has a substantially semicircular shape and is fastened in a cone block shape to the transmission together with the substantially semicircular fastening portion of the engine body. At this time, since a conventional starter mounting recess is not required in the fastening portion of the engine body, the shape of the fastening portion of the engine body with respect to the transmission can be a substantially complete cone block structure on both sides. The joint rigidity between the two can be improved.

According to the fourth aspect of the invention, the starter functions as a dynamic damper for the PPB longitudinal bending mode due to its mounting rigidity in the state of being attached to the fastening flange, so that the PPB in the longitudinal bending mode is effectively suppressed. be able to.

In the fifth aspect of the invention, the oil dropped from the engine body into the bulging portion of the oil pan returns to the oil sump portion from the bulging portion through the communicating portion. At this time, in the communicating portion, the check valve only allows the oil to flow from the bulging portion side to the oil reservoir portion side, and prevents the reverse flow from the oil reservoir portion to the bulge portion. This prevents the oil level on the swelling part side from becoming higher than the oil sump part, so that the swelling part swells even when the vehicle is in an operating state where the oil level on the swelling part side tends to fluctuate up and down. There will be no situation where the oil level on the part side becomes too high and the operation of the engine body is hindered.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 5 show an oil pan A according to this embodiment, the oil pan A is opened upward, and a mounting flange 1 for mounting on a lower surface portion of an engine body B is provided at the opening edge. It is set around. Further, a flange 2 for fastening with the automatic transmission C is formed in a substantially semicircular shape at the right end portion of FIG. 1, as shown in FIG. 3, and the fastening flange 2 is provided from both side walls and the bottom wall of the oil pan A. A reinforcing wall 3 having a cone block shape is extended to the peripheral edge of the.

A central portion of the bottom portion of the oil pan A on the fastening flange 2 side is bulged upward, and a space portion 4 for installing the starter a is formed on the lower surface of the central portion. . Further, the fastening flange 2 of the oil pan A
Both side portions of the side bottom portion are bulged downward from the central portion, whereby bulging portions 5 are formed so as to surround both sides of the space portion 4. The ends on both sides of the bulging portion 5 on the transmission C side are integrally connected to the fastening flange 2. On the other hand, a substantially rectangular opening 6 that opens the space 4 toward the transmission C is provided at the center of the fastening flange 2 of the oil pan A. Around the opening 6 of the fastening flange 2, there are three bolt holes 7 for mounting and fixing the starter a to the fastening flange 2.
It is provided in the place.

Inside the oil pan A, a partition wall 9 for partitioning the bulging portion 5 side from the oil sump portion 8 is provided. The bulging portions 5 are communicated with the oil sump portion 8 through the communicating holes 10 as communicating portions provided on both sides of the partition wall 9, and the communicating holes 10 are connected to the oil bulging portion 5 from the bulging portion 5 side. A check valve 11 is provided which allows only oil to flow to the side of the sump 8.
The check valve 11 is made of, for example, rubber having flexibility and oil resistance, has a strip shape, and can be closely attached to the surface of the partition wall 9 on the oil sump portion 8 side so as to close the communication hole 10.
It is sandwiched between the upper end portion and the partition wall 9.

According to this embodiment, the starter a is installed in the space portion 4 located on the lower surface of the central portion of the bottom portion of the oil pan A on the side of the fastening flange 2 and located in the central portion of the fastening flange 2 of the oil pan A. A ring gear attached to a flywheel (not shown) or a drive plate (not shown) is engaged between the engine-side fastening portion and the transmission C-side fastening portion through the opening 6. In this state, the starter a is located directly below the center line of the engine, so that the situation in which the starter a promotes PPB in the lateral bending mode can be avoided. Also, by changing the installation position of the starter a,
In the fastening portion of the engine body B, the conventional starter installation recess is not required, and the rigidity can be easily made uniform. On the other hand, a bulging portion 5 bulging downward from the center of the bottom portion of the oil pan A on the fastening flange 2 side surrounds the space portion 4 from both sides, and a transmission on both side walls of the bulging portion 5 Since the C-side end portion is integrally connected to the fastening flange 2, the bulging portion 5 forms a rib having a box-shaped cross section that is effective for ensuring bending rigidity and torsional strength of the power plant. In this way, the starter a is prevented from promoting the generation of PPB, and the coupling rigidity between the engine body B and the transmission C is improved, so that the PPB
The natural frequency at the time of occurrence can be deviated from the frequency component of the fundamental order during engine operation, which can reduce vibrations and vehicle interior noise.

Further, the fastening flange 2 has a substantially semicircular shape, and is fastened to the transmission C in a cone block shape together with a substantially semicircular fastening portion of the engine body B.
At this time, since the conventional starter installation recess is not required in the fastening portion of the engine body B, the shape of the fastening portion of the engine body B with respect to the transmission C has a substantially complete cone block structure on both the air supply side and the exhaust side. Therefore, the coupling rigidity between the engine and the transmission C can be improved.

Further, when the starter a is attached to the fastening flange 2, the starter a has a PPB due to its attachment rigidity.
Since it functions as a dynamic damper for the vertical bending mode, the PPB in the vertical bending mode can be effectively suppressed.

On the other hand, the oil that has fallen from the engine body B into the bulging portion 5 of the oil pan A passes through the communication hole 10 and returns from the bulging portion 5 to the oil sump portion 8. At this time, in the communication hole 10, the oil is allowed only to flow from the swelling portion 5 side to the oil sump portion 8 side by the check valve 11, and the backflow from the oil sump portion 8 to the swelling portion 5 is prevented. It This prevents the oil level on the bulging part 5 side from becoming higher than the oil sump part 8, so that the oil level on the bulging part 5 side is likely to fluctuate up and down, even in an operating state of the vehicle. It does not occur that the operation of the engine body B is hindered by the fact that the oil level on the side of the bulging portion 5 becomes too high to resist the rotational movement of rotating parts such as the crankshaft.

The opening 6 can also be used as a service hole for connecting the torque converter of the automatic transmission C and the drive plate, for example. In other words, even if the nut or the like is accidentally dropped during the installation work of the torque converter, the service hole is provided at the bottom of the engine, so that the nut and the like are prevented from getting between the engine and the transmission C. can do.

[0028]

As described above, according to the invention of claim 1, the bulging portion surrounds the space portion on both sides of the space portion of the oil pan, and the transmission side end portion of the bulging portion is oiled. By integrally connecting to the fastening flange of the pan, the vertical rigidity of the fastening flange in the oil pan can be secured by the bulging portion, and PPB in the vertical bending mode can be effectively suppressed.

According to the second aspect of the invention, since the starter is arranged in the space, the starter can be arranged directly below the engine body, so that the starter promotes PPB in the lateral bending mode. It is possible to avoid such a situation and to easily make the rigidity uniform in the fastening portion of the engine body.
PB can be suppressed sufficiently. As a result, in combination with the effect of the invention of claim 1, it becomes possible to shift the natural frequency when the PPB is generated from the frequency component of the fundamental order during engine operation, which results in vibration and vehicle interior noise. Can be reduced.

According to the third aspect of the present invention, the shape of the fastening portion between the engine body and the oil pan for the transmission can be made into a substantially complete cone block structure, and the coupling rigidity between the engine and the transmission can be improved. Can be improved.

According to the invention of claim 4, the starter is made of PP.
Since it can function as a dynamic damper for the vertical bending mode of B, PPB in the vertical bending mode can be effectively suppressed.

According to the invention of claim 5, the oil surface on the bulging portion side is higher than the oil reservoir portion by allowing only the outflow of oil from the bulging portion side to the oil reservoir portion side. Therefore, even if the oil level on the bulge side easily fluctuates up and down, avoid the situation that the oil level on the bulge side becomes too high and interferes with the operation of the engine body. You can

[Brief description of drawings]

FIG. 1 is a cross-sectional view taken along the line II of FIG. 2 showing an oil pan according to an embodiment of the present invention.

FIG. 2 is a plan view of an oil pan.

FIG. 3 is a front view of an oil pan.

4 is a sectional view taken along line IV-IV in FIG.

FIG. 5 is a left side view of the oil pan.

FIG. 6 is a plan view showing a PPB in a lateral bending mode in a conventional example.

[Explanation of symbols]

 2 Fastening flange 3 Reinforcing wall 4 Space 5 Swelling 6 Opening 8 Oil sump 10 Communication hole (communication) 11 Check valve A Oil pan B Engine body C Automatic transmission (transmission) a Starter

Claims (5)

[Claims] 1. A structure of an oil pan that is attached to a lower surface of an engine body, and has a fastening flange that is fastened to the transmission together with a fastening portion of the engine body for the transmission, the fastening of the oil pan. A space formed on the lower surface of the central portion of the flange side bottom portion and both sides of the fastening flange side bottom portion of the oil pan, and expand downward from the center portion so as to surround both sides of the space portion. Protruding bulge and provided in the center of the fastening flange of the oil pan,
An oil pan structure for an engine, comprising: an opening that opens the space toward the transmission, and a transmission-side end of the bulging portion that is integrally connected to a fastening flange. 2. The oil pan structure for an engine according to claim 1, wherein the starter is arranged in a space, and the starter arranged in the space passes through an opening to a flywheel or a drive plate. An oil pan structure for an engine, wherein the oil pan structure is configured to engage with a ring gear attached to the engine. 3. The engine oil pan structure according to claim 1 or 2, wherein the fastening flange has a substantially semicircular shape, and has a cone block shape together with the substantially semicircular fastening portion of the engine body. An oil pan structure for an engine, which is configured to be fastened to a transmission. 4. The engine oil pan structure according to claim 1, 2, or 3, wherein the starter is mounted on a fastening flange, and the mounting rigidity thereof makes it possible to provide a dynamic damper for a longitudinal bending mode of power plant bending. The oil pan structure of the engine, which is configured to function as. 5. The oil pan structure for an engine according to claim 1, 2, 3 or 4, wherein the bulging portion of the oil pan communicates with the oil sump portion through a communicating portion, and the communicating portion has a bulging portion. An oil pan structure for an engine, comprising a check valve for allowing only oil to flow from an outlet side to an oil sump side.