JPH0736114Y2 - Cylinder block reinforcement member structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION << Industrial Application Field >> The present invention relates to a reinforcing member structure for a cylinder block applied to a vehicle engine or the like.

<< Prior Art >> As is well known, a crankshaft of a vehicle engine or the like has a half-split main bearing integrally formed with a cylinder block, and a half split tightened and fixed to the main bearing portion. It is rotatably supported between the bearing cap and the bearing. And for a multi-cylinder engine,
The bearing cap is arranged as a plurality of individual parts.

Here, the bearing cap is subjected to vibration (vertical vibration) in the cylinder axis direction due to the explosive force when the engine is driven, etc., and the maximum explosive force is deviated from the upper fulcrum. Vibration (horizontal vibration), tilting vibration of the crankshaft in the axial direction (front-back vibration), etc. due to bending of the crankshaft. For this reason,
In order to suppress such vibration of the bearing cap, generally, a reinforcing member is provided between the cylinder block and the oil pan, and the reinforcing member supports the bearing cap from below in the axial direction of the cylinder.

As the reinforcing member, there is one described in Japanese Utility Model Laid-Open No. 59-34049. The proposed reinforcing member has a plate-like shape, and its peripheral edge portion is sandwiched between the lower end of the skirt portion of the cylinder block and the oil pan. A bearing cap fastening boss that is positioned directly below each of the bearing caps and supports the bearing caps from below is integrally projected upward in the widthwise central portion of the plate-shaped reinforcing member. Has been formed.

<Problems to be Solved by the Invention> However, in the above-mentioned conventional reinforcing member structure for a cylinder block, the bearing cap fastening boss on the upper surface side and the oil pan fastening bolt hole on the lower surface side close to the boss are fastened. They were placed close to each other on a plane, and the rigidity of the same part was high. Therefore, there is a problem that vibration of the bearing cap portion is easily transmitted to the oil pan via the reinforcing member, and the oil pan emits relatively high frequency noise due to the vibration of the bearing cap portion. And, this was particularly remarkable in a diesel engine or the like having a large explosion load.

The present invention has been made in view of such circumstances, and provides a reinforcing member structure for a cylinder block that can suppress vibrations transmitted from the bearing cap to the oil pan via the reinforcing member, thereby reducing noise. The purpose is to do.

<Means for Solving the Problems> In order to achieve the above object, the present invention is a dish-shaped reinforcing member provided between a cylinder block and an oil pan, and has a bearing cap fastening boss on the upper surface side thereof. In a reinforcing member structure of a cylinder block in which a flange with an oil pan fastening bolt hole is formed on the lower surface side thereof, the bearing cap is included in the oil pan fastening bolt hole of the flange. Those that are arranged close to the fastening boss and adjacent to each other in the direction orthogonal to the crankshaft are located apart from the bearing cap fastening boss on the outer side in the direction orthogonal to the axis of the crankshaft and at the same time. The vertical thickness of the flange portion between the oil pan fastening bolt holes that is located in this direction is greater than the thickness of the other portions of the flange portion. Form a thin portion that is even thinner.

<Operation> According to the present invention, among the bolt holes of the flange for oil pan fastening formed on the lower surface of the reinforcing member, those having a planar arrangement adjacent to the bearing cap fastening boss and adjacent to each other in the direction orthogonal to the crankshaft are provided. , The bearing cap fastening boss is located on the plane so as to be spaced outward in the direction orthogonal to the axis of the crankshaft, so that the vibration transmissibility between the reinforcing member and the oil pan is enhanced, and the rigidity is increased by tightening them. However, since it is arranged away from the bearing cap, the amount of vibration transmitted from the bearing cap to the oil pan is reduced.

Further, in the flange between the separated oil pan fastening bolt holes, that is, in the flange portion located at the lower portion of the bearing cap, the thickness in the vertical direction is set to be thinner than the thickness of other portions of the flange. Since the thin portion is formed, the rigidity of that portion is reduced, and the vibration damping effect in that portion is increased accordingly, so that the noise generation amount due to the oil pan vibration is reduced as much as possible.

<Example> An example of a reinforcing member structure for a cylinder block according to the present invention will be described below with reference to the drawings.

FIG. 1 is a longitudinal sectional structure of this embodiment, FIG. 2 is a plane structure,
FIG. 3 shows an enlarged cross-sectional structure of the main part.

This embodiment is an in-line 4-cylinder engine, and the cylinder block 1 of the engine has four cylinders 2a, 2b,
2c and 2d are formed. At the lower end of the cylinder block 1, half-shaped crank bearings 3, 4, 5, 6 and 7 are integrally formed between the cylinders 2a to 2d and at both ends. Half-divided bearing caps 8a, 8b, 8c, 8d, 8e are fastened and fixed to the crank bearing portions 3 to 7 from below, thereby forming a crank bearing for supporting the crankshaft 20. The bearing caps 8a to 8e are boss portions 10a, 10b, 11a, 11b, 12a, 12b, 13a, 13b, 14 of the reinforcing member 9 of the cylinder block arranged on the lower end side of the cylinder block 1.
It is also supported from below by a and 14b, and these bosses 10a-
14b penetrates through them and each bearing cap 8a-8e
The fixing bolts 15, 16, 17, 18, and 19 that are screwed into the are inserted.

The reinforcing member 9 has a substantially square shape in a planer shape and has a dish shape. The cylinder block 1 and each of the front and rear covers 2 thereof.
It has a size that covers the lower surface of 1,22. The upper edge of the reinforcing member 9 has the cylinder block 1 and the covers 21 and 22.
And a flange portion 23 for engaging and fixing in a sealed state. In addition, a substantially semicircular flange-shaped coupling portion 25 having a mating surface 24 with the end surface of the rotary member housing portion of the transmission case (not shown) is formed at the rear end portion. The connecting portion 25 is connected to the bottom wall 26 by a connecting wall 27 extending obliquely downward from the bottom wall 26 of the reinforcing member 9.

The bottom wall 26 of the reinforcing member 9 is a flat horizontal surface from the front side to the positions of the boss portions 13a, 13b corresponding to the fourth bearing cap 8d, and the fourth bearing cap 8d
The bosses 13a, 13b corresponding to the above are formed to have an inclined surface slightly upward toward the rear side. The boss portions 13a, 13b corresponding to the fourth bearing cap 8d are formed so as to project not only on the upper surface side of the bottom wall 26 but also on the lower surface side thereof, and a connecting rib for connecting the lower surface side protruding portions 13c, 13d. 29 is formed on the lower surface side of the bottom wall 26. The connecting rib 29 has bosses 13a, 13
The lower surface side protrusions 13c and 13d of b are connected to each other, and further extend laterally to form the respective lower surface side protrusions 13c and 13d and the rear side lower surface side ribs 30.
It connects a and 30b. Ribs on the rear bottom surface side 30
a and 30b are the pair of tightening bosses 28a and 28b at the rear end.
Extends in parallel to the rear end portion of the flange 31 which serves as an oil pan mating surface in the crankshaft direction. The flange 31 is provided on the lower surface of the horizontal bottom wall 26 located on the front side by the boss portions 13a and 13b corresponding to the fourth bearing cap 3d so as to overlap the flange portion 23.

Further, the bottom wall 26 inside the flange 31 as the oil pan mating surface has a plurality of oil return openings 36, 37, 38, 39, 40, 41 for each part partitioned by the connecting ribs 32, 33, 34. , 42,4
Three are provided.

In this, the bearing cap fastening bosses 13a, 13b in the oil pan fastening bolt hole 44 of the flange 31 are used.
Which are arranged in a plane adjacent to the crankshaft 20 in the direction orthogonal to the axis of the crankshaft 20 are sufficiently arranged outwardly in the direction orthogonal to the axis of the crankshaft 20 on the plane more than the bearing cap fastening bosses 13a, 13b. It is arranged in a separated manner. The oil pan fastening bolt hole 44a is a bag-shaped screw hole into which the fastening bolt is directly screwed.

Further, in the flange 31 portion between the oil pan fastening bolt holes 44a, 44a, the thin wall portion 31a, 31a whose vertical thickness t1 is set smaller than the wall thickness t2 of the other portion of the flange 31. ,
31a is formed. The thin portion 31a has a recessed shape with an upper surface recessed.

Further, the oil return openings 36, 37, in the oil pan 46,
38,39,40,41,42,43 Corresponding parts include baffle plate 45
Is provided.

According to the present embodiment configured as described above, the bolt holes 44 of the oil pan fastening flange 31 formed on the lower surface of the reinforcing member 9 are arranged in a plane close to the bearing cap fastening bosses 13a, 13b. Since the components 44a, 44a are arranged sufficiently apart from the bearing cap fastening bosses 13a, 13b outward in the direction orthogonal to the axis of the crankshaft 20 on the plane, vibration of the reinforcing member 9 and the oil pan 46 occurs. The high rigidity portion by tightening the bolts, which increases the transmissibility, is arranged apart from the bearing cap 8d, and the amount of vibration transmission transmitted from the bearing cap 8b to the oil pan 46 via the reinforcing member 9 is reduced.

In addition, the separated oil pan fastening bolt holes 44a, 44
The flange 31 between a, that is, the flange 31 located below the bearing cap, has a thin wall portion in which the vertical wall thickness is set smaller than the wall thickness of other portions of the flange 31.
Since the portion 31a is formed, the rigidity of the same portion is reduced, and the vibration damping effect in that portion is increased accordingly, so that the amount of noise generated by the vibration of the oil pan 46 is reduced.

In addition, the thin portion 31a of the flange 31 has its upper surface on the other bottom wall 26a.
Since the recessed shape is recessed from the upper surface, when the oil flowing down from the cylinder block side flows back to the oil pan 46 through the reinforcing member 9, the thin-walled portion 31 of the flange 31 is used.
After passing through the concave portion of “a”, it temporarily becomes a staying state, an air bleeding action is performed here, and it is possible to obtain the advantage that air inclusion in the oil in the oil pan 46 can be prevented as much as possible.

Further, the oil return openings 36, 37, in the oil pan 46,
Since the baffle plates 45 are provided at the portions corresponding to 38, 39, 40, 41, 42, 43, the oil level in the oil pan 46 is suppressed from being disturbed by the baffle plates 45, and the oil level can be stabilized. The baffle plate 45 is provided only along the inner peripheral surface of the oil pan 46 at the peripheral portion thereof, and the central portion side is in an open state, so that the oil cooling effect is not hindered and the oil temperature rises. Does not occur.

<Effect of the Invention> As described in detail above, according to the present invention, among the bolt holes of the oil pan fastening flange formed on the lower surface of the reinforcing member, the crankshaft is orthogonal to the crankshaft close to the bearing cap fastening boss. Since the planar arrangement adjacent to each other in the direction is spaced apart from the bearing cap fastening boss on the plane in the direction orthogonal to the crankshaft, those bolts that enhance the vibration transmissibility between the reinforcing member and the oil pan. The part where the rigidity is increased by tightening is located away from the bearing cap, which reduces the amount of vibration transmitted from the bearing cap to the oil pan through the reinforcing member as much as possible, and tightens the separated oil pan. Form a thin-walled part in the flange between the bolt holes, the thickness of which in the vertical direction is set to be smaller than the wall thickness of other parts of the flange. Therefore, the rigidity of that portion is lowered, and the vibration damping effect in that portion is increased accordingly, so that an excellent effect that the noise generation amount due to the oil pan vibration can be reduced as much as possible is exhibited.

[Brief description of drawings]

FIG. 1 is a partial vertical sectional view showing an embodiment of the present invention, FIG. 2 is a plan view, and FIG. 3 is a partially enlarged sectional view. 1 …… Cylinder block 8a ～ 8e …… Bearing cap 9 …… Reinforcement member 13a, 13b …… Bearing cap fastening boss 20 …… Crankshaft 31 …… Flange 31a …… Thin wall 46 …… Oil pan 44a …… Oil Pan fastening bolt holes

Claims (1)

[Scope of utility model registration request] 1. A dish-shaped reinforcing member provided between a cylinder block and an oil pan, wherein a bearing cap fastening boss is integrally projectingly formed on an upper surface side thereof, and an oil pan is formed on a lower surface side thereof. In a reinforcing member structure of a cylinder block in which a flange with a fastening bolt hole is formed, among the oil pan fastening bolt holes of the flange, arranged adjacent to the bearing cap fastening boss and adjacent to each other in the direction orthogonal to the crankshaft. Is placed on the plane more outwardly than the bearing cap fastening boss outward in the direction orthogonal to the axis of the crankshaft, and at the flange portion between the spaced oil pan fastening bolt holes. A thin cylinder portion having a vertical thickness smaller than that of the other portion of the flange portion. The reinforcing member structure of the click.