JP3089047B2 - Stiffener for engine / mission coupling reinforcement - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stiffener for reinforcing an engine / transmission coupling.

[0002]

2. Description of the Related Art A transmission having a flywheel and a torque converter is connected to a rear portion of an engine body. However, since the engine body and the transmission have a large mass, when the engine body and the transmission are relatively displaced, the engine body and the transmission are displaced. There is a danger that a large stress will be generated in the connecting portion of the engine and the connecting portion between the engine body and the transmission will be damaged. Therefore, it is necessary to strongly reinforce the connection between the engine body and the transmission. Also, a flywheel or a rotor of a torque converter having a large mass is attached to a crankshaft protruding from the rear part of the engine body. Therefore, among the bearings supporting the crankshaft, the rearmost bearing located at the rearmost part of the engine is a flywheel. The crankshaft portion carrying the wheel or the rotor is cantilevered. As a result, the portion of the crankshaft supported by the rearmost bearing is subjected to repeated bending loads, so that the rearmost bearing vibrates violently, and thus the rearmost bearing among the bearings generates the largest vibration noise. Therefore, in order to reduce the noise generated from the engine, it is necessary to cope with the vibration noise emitted from the rearmost bearing through the rear oil pan.

Therefore, in order to strongly reinforce the connection between the engine body and the transmission and to cut off noise emitted from the rear oil pan to the outside as much as possible, a substantially U-shaped cross-sectional shape is provided so as to cover the rear oil pan. The main body part extends in the longitudinal direction of the engine body and an end wall portion formed at one longitudinal end of the main body part, and corresponds to the upper end parts of the main body parts located on both sides of the rear oil pan, respectively. 2. Description of the Related Art A stiffener for reinforcing an engine / transmission coupling, which is fixed on a side wall surface of an engine body and has an end wall portion fixed to a transmission, is known (see Japanese Utility Model Publication No. Sho 62-29639).

[0004]

In this stiffener, the noise generated from the rear oil pan is blocked by the main body part by covering the rear oil pan with a space, so that the noise does not leak to the outside. Is intended. However, if the rear oil pan is covered by the main body part with a space in between, a large volume of space is created between the rear oil pan and the bottom of the inner wall surface of the main body part, so that noise emitted from the rear oil pan, that is, a pressure wave, is generated. The reflection between the rear oil pan and the bottom of the inner wall surface of the main body portion is repeated and overlapped with each other. As a result, the pressure wave is amplified, and the amplified pressure wave is transmitted from the opening end of the main body portion opposite to the end wall portion. Loud noise is emitted to the outside. Therefore, when such a stiffener is attached, the space between the engine body and the transmission can be strongly reinforced, but there is a problem that a larger noise is generated than when no stiffener is attached.

[0005]

According to the present invention, there is provided a body portion having a substantially U-shaped cross-sectional shape and extending in a longitudinal direction of an engine body so as to cover a rear oil pan. And an end wall portion formed at one end in the longitudinal direction of the main body portion. The upper end portions of the main body portions located on both sides of the rear oil pan are fixed on the corresponding side wall surfaces of the engine main body. An opening is formed on the bottom wall of the body below the rearmost bearing, which is the rearmost part of the engine, in the stiffener for reinforcing the engine and transmission coupling with the end wall fixed to the transmission. At the same time, a cylindrical rib extending from the periphery of the opening toward the rearmost bearing is formed in the main body.

Further, according to the present invention, in order to solve the above problems, a main body portion having a substantially U-shaped cross-sectional shape and extending in the longitudinal direction of the engine main body so as to cover the rear oil pan, End wall portions formed at one end in the longitudinal direction, the upper end portions of the body portions located on both sides of the rear oil pan are fixed on the corresponding side wall surfaces of the engine body, and the end wall portions are fixed. in fixed engine transmission coupling reinforcing stiffener to the transmission, the inner wall surface bottom portion of the body portion to form a plurality of ribs extending upwardly toward the rear oil pan on the inner wall surface bottom of the body portion facing the rear oil pan And between the rear oil pan
Ribs plurality of the inner space of the body portion formed
It is divided into a plurality of chambers by.

[0007]

According to the first aspect of the present invention, most of the vibration noise generated from the rearmost bearing passes through the cylindrical rib without being transmitted to the main body around the cylindrical rib and is emitted to the outside from the opening. You. According to the second aspect of the present invention, the vibration noise, that is, the pressure wave generated from the rearmost bearing and other parts is dispersed and transmitted to each small chamber. The pressure waves are attenuated by these peripheral walls because the small chambers are surrounded by peripheral walls that are close to each other. Further, even if the pressure waves are superimposed on each other in the small chambers, the pressure waves are not greatly amplified because the space volume is small. Therefore, the vibration noise emitted to the outside is reduced.

[0008]

Referring to FIGS. 6 to 8, 1 is an engine body, 2 is a transaxle integrally incorporating a transmission including a flywheel or a torque converter and a differential gear mechanism, 3 is a drive shaft, Numeral 4 indicates wheels. Transaxle 2 is transaxle 2
The transaxle 2 is fixed below the rear end of the engine body 1 via an end plate 5 that covers the end of the engine body 1. An oil pan 6 is attached to a lower end of the engine body 1. The rear lower end of the engine body 1 and the end of the transaxle 2 are connected to each other via a stiffener 7.

Referring to FIGS. 1 to 5, a stiffener 7 is shown.
Is a main body portion 8 having a substantially U-shaped cross-sectional shape so as to cover the rear portion of the oil pan 6 and extending in the longitudinal direction of the engine main body 1, and an end wall formed at one longitudinal end of the main body portion 8. And a portion 9. The main body portion 8 has upper wall surfaces 10 and 11 extending parallel to each other on both side edges thereof, and the bottom wall 12 of the main body portion 8 has a downwardly convex curved cross-sectional shape. The end wall portion 9 extends upward from the bottom wall 12 to substantially the same height as the upper wall surfaces 10 and 11 of the main body portion 8, and the upper wall surface 13 of the end wall portion 9 is substantially the same as the upper wall surfaces 10 and 11. It extends substantially horizontally between the ends of the upper wall surfaces 10 and 11 at a height. Therefore, one end of the internal space formed in the main body portion 8 is closed by the end wall portion 9. On the other hand, there is no end wall at the longitudinal end 14 of the body part 8 opposite the end wall part 9 and therefore the body part 8
The other end 14 of the internal space formed therein is open to the outside. As can be seen from FIG. 5, the bottom wall 12 is the end wall portion 9
, And gradually increases toward the longitudinal end portion 14 of the main body portion 8, so that the depth of the bottom of the inner wall surface of the main body portion 8 gradually decreases as the distance from the end wall portion 9 increases.

A pair of arms 15 and 16 extending upward from the upper wall surfaces 10 and 11 are integrally formed at the ends of the upper wall surfaces 10 and 11 opposite to the end wall portion 9. Bolt holes 17 and 18 are formed in 16 respectively. The arm 15 is fixed to one side wall surface of the engine body 1 by a bolt inserted into the bolt hole 17, and the arm 16 is fixed to the other side wall surface of the engine body 1 by a bolt inserted into the bolt hole 18. Thereby, the stiffener 7 is fixed to the engine body 1. On the other hand, the end wall portion 9 has a peripheral flange portion 19 protruding outward from the outer peripheral wall surface of the main body portion 8, and a plurality of bolt holes 20 are formed in the peripheral flange portion 19. The peripheral flange portion 19 is fixed to the end face of the transaxle 2 via the end plate 5 by a bolt inserted into the bolt hole 20, whereby the stiffener 7 is fixed to the transaxle 2. Therefore, the engine body 1 and the transaxle 2 are firmly connected by the stiffener 7, and the connecting portion between the engine body 1 and the transaxle 2 is strongly reinforced by the stiffener 7.

A pair of lateral ribs 2 extending laterally of the stiffener 7 are spaced apart from each other on the bottom of the inner wall surface of the main body portion 8.
1, 22 are integrally formed. These horizontal ribs 21 and 22 extend vertically to the vicinity of the oil pan 6 as can be seen from FIG. Further, a pair of vertical ribs 23, 24 extending from the horizontal rib 21 to the end wall portion 9 in the longitudinal direction of the stiffener 7 are formed integrally on the bottom of the inner wall surface of the main body portion 8 at intervals. These vertical ribs 23, 24 have the same height as the horizontal ribs 21, 22. In the embodiment shown in FIGS. 1 to 5, the internal space of the stiffener 7 is divided into four small chambers 25, 26, 27, 28 by these horizontal ribs 21, 22 and vertical ribs 23, 24. An opening 29 having substantially the same cross-sectional area as the small chamber 27 is formed on the bottom wall 12 below the small chamber 27 located at the center of the end wall portion 9 among the small chambers 25, 26, 27, 28. Therefore, the small chamber 27 is open to the outside through the opening 29. The bottom of the remaining small chambers 25, 26, 28 is the bottom wall 1.
2 closed.

In FIG. 5, a chain line 31 indicates a rearmost bearing located at the rearmost portion of the engine body 1 among the bearings for supporting the crankshaft 30, and this rearmost bearing 3
An opening 29 is formed directly below the opening 1. The periphery of the small chamber 27 formed by the opening 29 is a horizontal rib 21 and a pair of vertical ribs 2.
3, 24 and the end wall portion 9, but the end wall portion 9 can be regarded as a rib extending upward from the bottom wall 12, so that the rear end bearing is formed in the main body portion 8 from the periphery of the opening 29. That is, a cylindrical rib extending toward 31 is formed.

As described above, the rearmost bearing 31 generates a large vibration noise, and this large vibration noise is emitted to the outside of the oil pan 6 through the rear portion of the oil pan 6. However, since a cylindrical rib extending from the peripheral edge of the opening 29 toward the rearmost bearing 31 is formed in the main body portion 8, most of the vibration noise generated in the rearmost bearing 31 passes through the cylindrical rib. It is discharged through the opening 29 to the outside. That is, the vibration noise generated in the rearmost bearing 31, that is, the pressure wave is amplified inside the stiffener 7, and the large noise is not emitted to the outside from the longitudinal end 14 of the main body portion 8, so that the noise is emitted to the outside. It is possible to suppress the generated vibration noise.

On the other hand, some of the vibration noise generated in the rearmost bearing 31 and the vibration noise generated in the other part are dispersed and transmitted to the other small chambers 25, 26, 28 through the rear part of the oil pan 6. You. However, each small room 25,26,2
8 is horizontal ribs 21 and 22 and vertical ribs 23 and 24 which are close to each other.
And so on, the vibration noise, that is, the pressure wave, is attenuated by these peripheral walls. Further, even if the pressure waves are superimposed on each other in the small chambers 25, 26, 28, the pressure waves are not increased so much because the space volumes of the small chambers 25, 26, 28 are small. Therefore, the longitudinal end 14 of the body part 8
The vibration noise emitted from the main body 8 is reduced, and the vibration noise emitted to the outside can be reduced as compared with the case where the internal space of the main body 8 is not divided into the small chambers 25, 26, 28.

When a cylindrical rib extending from the periphery of the opening 29 toward the rearmost bearing 31 is formed in the main body 8, the internal space of the main body 8 is not particularly divided into a plurality of small chambers. Although the vibration noise emitted to the outside can be reduced, the vibration noise emitted to the outside can be further reduced by dividing the internal space of the main body portion 8 into a plurality of small chambers indicated by reference numerals 25, 26 and 28. can do. On the other hand, the body part 8
If the interior is divided into a plurality of small chambers, the vibration noise emitted to the outside can be reduced by itself, so that when the inside of the main body 8 is divided into a plurality of small chambers, the opening 29 is not particularly required. Vibration noise emitted to the outside can be reduced. However, as described above, if the opening 29 is formed, the vibration noise emitted to the outside can be further reduced.

[0016]

According to the present invention, it is possible to reduce the vibration noise emitted to the outside via the stiffener while strongly reinforcing the connection between the engine body and the transmission.

[Brief description of the drawings]

FIG. 1 is a perspective view of a stiffener.

FIG. 2 is a plan view of a stiffener.

FIG. 3 is a side view of the stiffener taken along arrow III in FIG. 2;

FIG. 4 is a cross-sectional view of the stiffener taken along line IV-IV in FIG. 2;

FIG. 5 is a side view of a stiffener.

FIG. 6 is a diagram showing the entire drive system.

FIG. 7 is a side view of an engine body and a transaxle.

FIG. 8 is a perspective view of an engine body and a transaxle showing a state where a stiffener is removed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Engine body 2 ... Transaxle 6 ... Oil pan 7 ... Stiffener 8 ... Body part 9 ... End wall part 12 ... Bottom wall 21,22 ... Horizontal rib 23,24 ... Vertical rib 25,26,27,28 ... Small chamber 29 ... opening 30 ... crankshaft 31 ... rearmost bearing

Claims (2)

(57) [Claims] 1. A main body portion having a substantially U-shaped cross-section and extending in a longitudinal direction of an engine main body so as to cover a rear oil pan, and an end wall formed at one longitudinal end of the main body portion. In the stiffener for reinforcing the engine and transmission coupling, the upper end portions of the main body portions located on both sides of the rear oil pan are fixed on the corresponding side wall surfaces of the engine body and the end wall portions are fixed to the transmission. An opening is formed on the bottom wall surface of the main body portion below the rearmost bearing located at the rearmost portion of the engine among the bearings supporting the crankshaft of the engine, and extends from the periphery of the opening toward the rearmost bearing. A stiffener for reinforcing engine and transmission coupling with cylindrical ribs formed in the main body. 2. A main body portion having a substantially U-shaped cross-section so as to cover the rear oil pan and extending in the longitudinal direction of the engine main body, and an end wall formed at one longitudinal end of the main body portion. And an engine / transmission coupling stiffener in which the upper end portions of the body portions located on both sides of the rear oil pan are fixed on the corresponding side wall surfaces of the engine body and the end wall portions are fixed to the transmission. A plurality of ribs extending upward toward the rear oil pan are formed on the bottom surface of the inner wall surface of the main body portion facing the rear oil pan, and
The internal space of the body portion is formed between the section oil pan
Engine divided into multiple compartments by multiple ribs
Stiffener for reinforcement of mission connection.