JPH0629486Y2 - Engine cylinder block reinforcement device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION << Industrial Application Field >> The present invention relates to a cylinder block reinforcing device for an engine, and in particular, a plate-shaped reinforcing member is fastened together with an oil pan to the lower edge of the cylinder block, and The present invention relates to an engine cylinder block reinforcing device in which a reinforcing member and a bearing cap are fastened together.

<< Prior Art >> A cylinder block reinforcing device for an engine of this type has been proposed in Japanese Utility Model Laid-Open No. 59-34049. In this proposal, a plate-shaped reinforcing member is provided between the lower end of the skirt portion of the cylinder block and the oil pan by sandwiching the peripheral portion between them, and the reinforcing member has a bearing portion of the crankshaft provided at the lower end of the cylinder block. Is formed immediately below the joint to form a coupling portion for coupling the bearing cap of the bearing, and the rigidity around the skirt portion of the cylinder block and the main bearing is enhanced.

<< Problems to be Solved by the Invention >> By the way, if the above-mentioned reinforcing member is to be applied to a half-skirt type engine, a flange is formed on the peripheral portion of the reinforcing member, and this flange portion is used for the cylinder block / skirt. It is necessary to secure the escape of the crankshaft portion, the bearing cap portion and the like by making the center portion be largely depressed downward in a dish shape while being sandwiched between the lower end of the portion and the oil pan.

Further, if the plate-shaped reinforcing member completely shuts off the upper crank chamber side part and the lower oil pan side part, the movement of gas in the crank chamber due to the piston reciprocating motion of each cylinder is hindered. , This increases resistance and reduces engine efficiency.Therefore, the plate-shaped reinforcing member has an upper crank chamber side portion and a lower oil pan side portion in the portion immediately below each cylinder. It is necessary to form a bottom hole for ventilation to communicate with.

Therefore, the rigidity of the plate-shaped reinforcing member itself is reduced in terms of shape, and it becomes difficult to obtain sufficient rigidity desired as a reinforcing device for the cylinder block.

Therefore, in order to secure sufficient rigidity, it is conceivable that the plate-shaped reinforcing member is further reinforced with a reinforcing member. However, after the plate-shaped reinforcing member is pressed, the productivity or after the reinforcing member is reinforced. From the standpoint of strength, the plate-shaped reinforcing member reduces the unevenness of the relief parts such as the crankshaft and bearing cap formed by recessing it in the dish shape, and the reinforcing member has a U-shaped cross section. Then, the bearing cap may be fixed directly below the bearing cap along the direction orthogonal to the crankshaft and fixed on the reinforcing plate, and the bearing cap may be brought into contact with the reinforcing member portion so that they are fastened and coupled.

However, if the plate-shaped reinforcing member is further reinforced by the reinforcing member in this manner, not only the weight of the reinforcing member is increased, but also the bolt length for fastening the bearing cap is increased and the weight thereof is increased. There is a problem that the effect of suppressing the inclination of the bearing cap is weakened because the distance between the tightening portions from the portion to the bearing cap becomes long.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a cylinder block reinforcing device for an engine, which has a large reinforcing effect and is as lightweight as possible.

<< Means for Solving the Problems >> In order to achieve the above object, the present invention has an engine cylinder block reinforcing device configured as follows.

In a cylinder block reinforcing device for an engine, wherein a reinforcing plate is provided by being fastened to a lower end of a skirt portion of a cylinder block and a bearing cap of a main bearing that axially supports a crankshaft, the reinforcing plate is provided on the bottom wall portion and the bottom wall portion. The bearing cap is formed into a substantially dish-shaped cross-sectional shape having side wall portions raised from both sides and flange portions extending laterally from upper edges of the both side wall portions and fastened to the skirt portion. In the bottom wall portion located directly below,
A reinforcing member having a U-shaped cross section that is long in the direction orthogonal to the crankshaft is provided with its open side fixed to the bottom wall, and the bearing cap is abutted and fastened to the upper wall of the reinforcing member. Is formed, and an opening for inserting a fastening bolt is formed in the bottom wall portion facing the connecting portion, and the opening is folded back from both side edges of the opening in the direction orthogonal to the crankshaft. And a bent piece whose tip is located close to the upper wall of the reinforcing member.

<Operation> According to the present invention having the above-described configuration, the bearing cap is abutted against and fastened to the upper wall of the reinforcing member having a U-shaped cross section provided on the bottom wall of the reinforcing plate. The bolt is inserted through the opening formed in the bottom wall portion of the reinforcing plate facing the connecting portion and fastens the upper wall of the reinforcing member and the bearing cap, so the distance between the tightening portions by the bolt becomes extremely short, As a result, the bearing cap is prevented from falling down as much as possible.

Further, the decrease in strength due to the formation of the opening is compensated by being reinforced by the bending piece and the reinforcing member provided on the peripheral edge of the opening.

<< Embodiment >> A preferred embodiment of a cylinder block reinforcing device for an engine according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows a reinforcing member 1 for an in-line four-cylinder engine. This reinforcing member 1 includes a reinforcing plate 2 and three reinforcing members 3
Welded in the state that this is attached to the engine
A cross section taken along the line II-II is shown in FIG. 2, and III-III in FIG.
The cross section taken along the line arrow is shown in FIG.

In FIG. 2, 4 is a cylinder block, 5 is a skirt portion of the cylinder block 4, 6 is an oil pan, 7 is a rail portion of the oil pan, and 8 is a cylinder block / skirt portion 5.
Is a bolt for fastening the reinforcing member 1 and the oil pan rail portion 7 according to the present invention together under the bolt. In addition, 9 is a crankshaft, 10 is a main bearing cap of a main bearing for attaching the crankshaft 9 to the cylinder block 4, and 11
Is a piston, and 12 is a connecting rod. Since the engine is an in-line 4-cylinder engine, there are five main bearing caps 10.

As shown in FIGS. 1 to 3, the reinforcing member 1 is mainly composed of a plate-shaped reinforcing plate 2 that is curved and formed into a substantially dish shape. The reinforcing plate 2 includes a bottom wall portion 13 and a bottom wall portion 13. Side wall portions 14 rising from both sides of the wall portion 13, and a flange portion 15 extending laterally from an upper edge of the side wall portion
And have. Both flange portions 15 are fixed to the cylinder block / skirt portion 5 together with the oil pan / rail portion 7 with bolts 8.

At both ends of the bottom wall portion 13 of the reinforcing plate 2 in the crank axis direction, wall-shaped raised portions 16 that are long in the direction orthogonal to the crank axis are formed to rise. A receiving metal fitting 18 is provided on the upper surface of the raised portion 16.
Of the individual main bearing caps 10, the caps 10 are in contact with the lower portions of the caps 10 at both ends, and are fastened to the caps 10 by bolts (not shown) that penetrate the receiving fittings 18 from the lower surface of the reinforcing plate 2. ing. That is, the upper surface of the raised portion 16 serves as a connecting portion 17 with the cap 10.

On the other hand, the three reinforcing members 3 of the reinforcing member 1 are correspondingly fastened to the three middle caps 10 of the five main bearing caps 10. That is,
The reinforcing member 3 is made of sheet metal having a U-shaped cross section and is long in the direction orthogonal to the crankshaft 9, and a flange portion 3b is formed at the open end of the side wall 3a. Each of the reinforcing members 3 is located immediately below the bearing cap 10 in the middle portion, and the flange portion 3b is welded and fixed to the upper surface of the bottom wall portion 13 of the reinforcing plate 2. Further, both end sides of the reinforcing member 3 rise from the bottom wall portion 13 of the main body plate 2 along the side wall portion 14 and reach the vicinity of the flange 15.

And also on the upper surface of the upper wall portion 3c of the reinforcing member 3,
Similar to the raised portion 16 described above, a receiving fitting 20 that is brought into contact with the lower portion of the main bearing cap 10 is provided, and a coupling portion 21 is formed therein. Then, the bolt 19 is received from the lower surface of the upper wall portion 3c of the reinforcing member 3 to the receiving fitting 2
It is adapted to be passed through 0 and fastened to the cap 10.

On the other hand, the bottom wall portion 13 of the reinforcing plate 2 faces the coupling portion 21 of the upper wall portion 3c of the reinforcing member 3 and the bolt 19
An opening 22 is formed for inserting the. In this embodiment, the opening 22 is formed in a rectangular shape that is long in the direction orthogonal to the crankshaft, but both side edges 2 facing each other in the direction orthogonal to the crankshaft.
The bent piece 23 is provided on the 2a and is folded back upward so that its tip portion is close to the upper wall portion 3c of the reinforcing member 3.

As shown in FIG. 1 and FIG. 3, the reinforcing plate 2
A relief portion 24 of the crankshaft 9 (to be exact, a large end portion of the connecting rod 12) is formed in a portion immediately below each cylinder of the piston so as to bulge further downward. A ventilation hole 25 is provided for smoothing the gas flow on the rear surface side of the piston 11 due to the reciprocating motion and preventing an increase in back pressure.

Therefore, in the cylinder block reinforcing device for an engine thus configured, the reinforcing plate 2 formed by recessing the central portion downward greatly extends from the bottom wall portion 13 to the side wall portions 14
Is reinforced by a reinforcing member 3 having a U-shaped cross section, which is arranged long along the direction orthogonal to the crankshaft, and its rigidity is enhanced.

Further, the reinforcing member 3 is located immediately below the main bearing cap 10 at each intermediate portion, and the upper wall portion 3 thereof is provided.
The coupling portion 21 formed in c is brought into contact with the cap 10 and fastened with the bolt 19. At this time, the bolt 19 is inserted through the opening 22 formed in the bottom wall portion 13 of the reinforcing plate 2 so as to face the coupling portion 21, and fastens and fixes the upper wall portion 3c and the cap 10. The distance between the fastening parts from the head part to the cap 10 is extremely short, so that the cap 10 can be prevented from falling down as much as possible, and the rigidity around the cap 10 can be improved.

Further, since the opening 22 for inserting the bolt 19 is formed in the bottom wall portion 13 of the reinforcing plate 2, there is a concern that the strength may be reduced due to this, but along the opening 22, the reinforcing member 3 is formed in the crankshaft orthogonal direction. Has a side wall 3a, and a bent piece 23 formed by being folded back upward is provided at both side edges of the opening 22 facing in the direction orthogonal to the crank axis, so that they are reinforced and sufficiently supplemented.

Further, when the reinforcing member 1 is mounted, the cylinder block 4 is turned upside down, the reinforcing member 1 is covered from above, and the bolts 8 and 19 are fastened, but the tip end of the bent piece 23 is the reinforcing member 3. Since it is close to the upper wall portion 3c of the bearing cap 10, even if the bolt 19 that is fastened to the bearing cap 10 is accidentally dropped onto the reinforcing member 3, there is a gap between the reinforcing member 3 and the side wall portion 14 of the reinforcing plate 2. There is no concern that the bolt 19 will roll down, and workability during assembly is improved.

In addition, in this embodiment, since a slight gap is formed between both side ends of the upper wall portion 3c of the reinforcing member 3 and the side wall portion 14 of the reinforcing plate 2, from this gap, lubricating oil can be provided between them. Although the mist component enters, it returns from the opening 22.

<Effect> As described in detail above, according to the engine cylinder block reinforcing device of the present invention, the bearing cap is provided on the upper wall portion of the reinforcing member having a U-shaped cross section provided on the bottom wall portion of the reinforcing plate. The bolts are brought into contact with each other and fastened to each other, but the fastening bolts are inserted through the openings formed in the bottom wall portion of the reinforcing plate to face the joint portion and fasten the upper wall portion of the reinforcing member and the bearing cap. Therefore, the distance between the tightening portions by the bolts is extremely short, and the tilting of the bearing cap is suppressed as much as possible. Further, the decrease in strength due to the formation of the opening is compensated by being reinforced by the bending piece and the reinforcing member provided on the peripheral edge of the opening.

[Brief description of drawings]

FIG. 1 is a plan view of an embodiment of a reinforcing member used in a cylinder block reinforcing device for an engine according to the present invention;
The figure is a sectional view taken along the line II-II of FIG. 1 with the reinforcing member attached to the engine, and FIG. 3 is a sectional view taken along the line III-III of FIG. 1 ... Reinforcement member, 2 ... Reinforcement plate 3 ... Reinforcement member, 3a ... Upper wall part 4 ... Cylinder block 5 ... Skirt part, 6 ... Oil pan 7 ... Rail part, 8 ... Bolt 9 ...... Crankshaft 10 ...... Main bearing cap 11 ...... Piston 12 ...... Connecting rod 13 ...... Bottom wall portion, 14 ...... Sidewall portion 15 ...... Flange portion, 19 ...... Bolt 20 ...... Receiving metal fitting, 21 ...... Coupling part 22 …… Opening, 23 …… Bending piece

Claims (1)

[Scope of utility model registration request] 1. A cylinder block reinforcing device for an engine, wherein a reinforcing plate is provided by being fastened to a lower end of a skirt portion of a cylinder block and a bearing cap of a main bearing that pivotally supports a crankshaft, wherein the reinforcing plate is a low wall portion. It is formed in a substantially dish-shaped cross-sectional shape having side wall portions raised from both sides of the bottom wall portion and flange portions extending laterally from upper edges of the both side wall portions and fastened to the skirt portion. A reinforcing member having a U-shaped cross section that is long in a direction orthogonal to the crankshaft is provided on the upper surface of the bottom wall portion located directly below the bearing cap, with its open side fixed to the bottom wall portion, A coupling portion is formed on the upper wall of the reinforcing member to abut and fasten the bearing cap, and an opening for inserting a fastening bolt is formed in the bottom wall portion facing the coupling portion. A cylinder block for an engine, characterized in that a bent piece is formed on each side edge of the opening in the direction orthogonal to the crankshaft and a tip portion of which is folded back from the opening so that a tip portion thereof is close to the upper wall of the reinforcing member. Reinforcement device.