JPH08210355A - Bearing device - Google Patents

Abstract

PURPOSE: To realize the close attachment of half-split bearing devices at the intermediate position where the uniform surface of a certain degree is secured on the end face of the half-split parts in the half-split type bearing devices to be fixed to a housing. CONSTITUTION: An end face 21a1 of a first connecting rod metal half-body 21a of first and second connecting rod metal half-bodies 21a, 21b to constitute a connecting rod bearing 21 is formed of projecting semi-circular shape of the prescribed radius R. An end face 31a1 of a first main metal 31a of first and second main metal half-bodies 31a, 31b to constitute a main bearing 31 is formed of projecting semi-circular shape of the prescribed radius R.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called half type bearing device fixed to a housing.

[0002]

2. Description of the Related Art Generally, a half-split bearing is used as a bearing in an engine crankshaft or a connecting rod bearing attached to the crankshaft. The half-split bearing is used as a housing. Butt inside and tightly fixed.

FIG. 5 is a block diagram of a connecting rod attached to a conventional crankshaft. In FIG. 5, the bush 12 is press-fitted into the small end 11 a at one end of the connecting rod 11, and a piston (not shown) is attached via the piston pin 13 fitted in the bush 12.

Further, the big end 11b at the other end of the connecting rod 11 is formed in a semicircular shape, and the first bearing half body 15a constituting one of the half bearings 15 is arranged in the big end 11b. To be done. On the other hand, a bearing cap 16 as a housing is formed in a semi-circular shape, and in this bearing cap 16, a second bearing half body 15b constituting the other half of the half-divided bearing 15 is arranged. This half bearing 15 (first and second bearing halves 15
a, 15b) is a metal base (15 ₁ ) such as a steel plate on which an alloy layer (15 ₂ ) of aluminum alloy or the like is formed. The first and second bearing halves 15a, 15b are halved. The end faces (15a ₁ , 15b ₁ ) are formed in a flat shape (see FIG. 6B).

Then, the first portion is provided between the big end 11b of the connecting rod 11 and the bearing cap 15.
Bearing half 15a and second bearing half 15b
And their end faces (15a ₁ , 15b ₁ ) are butted against each other, and the big end 11 is secured by the bolt 17a and nut 17b
b and the bearing cap 15 are fastened and fixed to fix the first and second bearing halves 15a, 15
b is fixed tightly. In this case, the first and second bearing halves 15a, 15b are formed with protrusions 18a, 18b, and the big end 11b and the bearing cap 16 are recessed to fit with the protrusions 18a, 18b. 19a and 19b (19a is not shown in the figure) are formed to position the first and second bearing halves 15a and 15b.

The first and second bearing halves 15
As another method for positioning a and 15b, for example, the method described in Japanese Utility Model Laid-Open No. 12717/1985 is known. When this is applied to FIG. 5, the connecting rod 11 and the bearing cap 16 are formed by breaking and splitting by integral molding.
Inside the big end 11b of the and the bearing cap 1
Positioning pin members are respectively implanted in the inside of 6, while
The first and second bearing halves 15a and 15b are each formed with a small hole to be fitted with the positioning pin member, whereby the connecting rod and the bearing cap are positioned on the rough surface to be broken, and the pin member and the small hole are formed. Thus, the first and second bearing halves 15a, 15b are accurately and surely positioned. In this case, the first and second
The half-divided end faces of the bearing halves 15a and 15b are formed in a flat shape and abutted against each other as described above.

By the way, in order to closely fix the half bearing 15 to the housing composed of the big end 11b and the bearing cap 16, for example, the second bearing half 15b is used as a housing (bearing cap 1).
It is performed to be longer than the inner circumferential length of 6).

Therefore, FIG. 6 shows an explanatory view of fixing the half bearing of FIG. As shown in FIGS. 6 (A) and 6 (B), the second bearing half body 15 b is formed longer than the inner circumference of the bearing cap 16 and is fitted into the bearing cap 16. One end is projected from the bearing cap surface by a predetermined length. This protruding portion d is what is called a crash height, and corresponds to the "interference" in the cylindrical bearing.

By providing this crush height, the housing (big end 11b and bearing cap 1
When fastened in 6), the length portion of the crush height is elastically deformed to form a interference. That is,
In general, the interference of a half-divided type bearing cannot be measured directly, so it is managed by a crush height as a substitute.

[0010]

However, the end surfaces of the first and second bearing halves 15a and 15b described above are formed in a flat shape, and at the time of fastening, the end surfaces should be in close contact with each other. In some cases, due to uneven processing tolerances and variations in the amount of compression at the ends, non-uniform deformation is caused by local stress, and surface contact does not occur, but contact occurs at the ends in the thickness direction.

That is, when the first bearing half body 15a indicated by the broken line in FIG. 6B comes into contact with the inner peripheral end a of the second bearing half body 15b, the alloy layer 15 _{2 on} the bearing sliding surface is separated. , And when it comes into contact with the outer peripheral edge b, the bearing 15
However, there is a problem that it may float from the housing (the big end 11b and the bearing cap 16) or cause poor adhesion. This is not limited to the bearing 15 of the connecting rod 11, but there is a similar problem with a half-shaped main bearing of the crankshaft.

Therefore, the present invention has been made in view of the above problems, and provides a bearing device in which an end surface of a half-divided portion is formed in a protruding arc shape so as to be in close contact at an intermediate position where a uniform surface is secured to some extent. The purpose is to provide.

[0013]

In order to solve the above-mentioned problems, in the present invention, bearing halves divided into halves are butted and tightly fixed to a housing. In a bearing device in which a bearing half has a crash height protruding from the housing to which it is fitted, at least one end face of the bearing half to be butted is formed in a protruding arc shape.

[0014]

As described above, in the present invention, at least one end surface of the bearing half body is formed in the shape of a projecting arc, and they are butted and fixed to the housing. As a result, it is possible to prevent the occurrence of non-uniform deformation by contacting at the intermediate position where a uniform surface is secured to some extent without abutting at the end of the end surface when closely fixing.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a block diagram of an embodiment of the present invention.
FIG. 1 (A) shows a connecting rod bearing 21 as a bearing device that is interposed when a connecting rod is attached to a crankshaft, which will be described later, and is a half-divided type. That is, in the connecting rod bearing 21, the first connecting rod metal half body 21a, which is a bearing half body, and the second connecting rod metal half body 21b are divided into end faces 21a ₁ and 21b ₁ (see FIG. 1C). It is formed by butting, and one end face (21
a ₁ , 21b ₁ ) are formed in a protruding arc shape (see FIG. 1).
(C) will be described).

The first and second connecting rod metal halves 21a and 21b are integrally formed with the protrusions 22a and 22b, respectively, and as shown in FIG. The housing 23 (see FIG. 1C) composed of the end and the bearing cap is positioned by being fitted into a recess formed in the inner peripheral surface of the housing 23.

This connecting rod bearing 21 has an alloy layer 21 ₂ formed on the inner peripheral surface of a metal base 21 ₁ , and for that purpose conditions such as non-seizure resistance, corrosion resistance, and fatigue resistance are required. Generally, white metal, kelmet metal, aluminum metal, etc. are used.

By the way, the white metal is obtained by sticking steel as the metal base 21 ₁ of the back metal and sticking platinum alloy such as tin, lead, antimony and zinc as the alloy layer 21 _{2 on the} surface thereof. Kelmet metal is made of steel with a metal backing 21 ₁ and an alloy layer 21 of copper and lead alloy on its surface.
_It is attached as ₂ . In addition, aluminum metal is obtained by welding a steel plate as a metal base 21 ₁ of a back metal and welding an alloy of aluminum and tin as an alloy layer 21 _{2 on the} surface thereof.

Further, FIG. 1B shows a main bearing 31 as a bearing device attached to a main shaft of a crankshaft, which will be described later, and is of a half-divided type which is divided in half like the connecting rod bearing 21. Is. Also in this main bearing 31, the end surfaces (31a ₁ , 31b) obtained by dividing the first main metal half body 31a and the second main metal half body 31b, which are bearing half bodies, are divided.
₁ ) butted at one end face (31a ₁ )
Are formed in a protruding arc shape.

In this case, an oil groove 32 is formed on the inner peripheral surface of the second main metal half body 31, and a hole 33 for supplying oil is formed on the oil groove 32. The first and second main metal halves 31a and 31b are integrally formed with protrusions 34a and 34b, respectively, and a housing 36 (FIG. 1C) is a crankcase in which a crankshaft (not shown) is installed. , (See FIG. 4) to be positioned by fitting into a recess formed on the inner peripheral surface.

The main bearing 31 is made of the same material as the connecting rod bearing 21 and has a metal base 3 formed therein.
The alloy layer 31 ₂ is formed on 1 ₁ . By the way, the main bearing 31 is attached to the main shaft of the crankshaft as described above, and at that time, crank washers 35a and 35b are arranged on both sides in the axial direction to prevent looseness in the thrust direction ( 2 and 3). These crank washers 35a, 35b
Is also divided into halves and is composed of washer halves 34a ₁ , 35a ₂ , 35b ₁ , 35b ₂ .

Therefore, as shown in FIG. 1C, when the first connecting rod metal half body 21a (first main metal half body 31a) is fitted to the inner peripheral surface of the housing 23 (36). In addition, one end portion is formed longer than the inner circumference of the housing 23 (36) so as to have a crush height for protruding a predetermined length D from the upper surface of the housing 23 (36), and the end surface 21a ₁ ( 31a ₁ ) is formed in an R-shaped arcuate shape in the thickness direction as described above.
In this case, the end face of the other end of the first connecting rod metal half body 21a (first main metal half body 31a) is formed in a flat shape (a similar arc shape may be used), and the housing 23
It shall be located on the upper surface of (36).

On the other hand, the first connecting rod metal half 21a
An end surface of the second connecting rod metal half body 21b (first main metal half body 31b) that is abutted with the (first main metal half body 31a) is formed in a flat shape as shown by a broken line. End faces 21a ₁ (31a ₁ ), 21b
_{When 1} (31b ₁ ) is abutted, it is abutted at an intermediate position in the thickness direction where a uniform surface is secured to some extent. That is, the end faces 21a ₁ (31a ₁ ) and 21b ₁ (3
It is possible to make a stable contact without hitting the end of 1b ₁ ).

By the way, the end face 21a ₁ (31
The curvatures of R of a ₁ ), 21b ₁ (31b ₁ ) are constant in the axial direction, but in view of the case where poor adhesion may occur in the axial direction, the convex arcuate R in the axial direction is also used. It may be formed into a spherical shape as a whole so that more stable adhesion can be obtained.

Next, FIG. 2 shows a block diagram of a crankshaft in which the bearing of FIG. 1 is used. Also, FIG.
2 shows a partial sectional view of FIG. 2 and 3,
Crankshaft 41 is intended for an automobile engine 4 cylinders, a crankcase crank journal 42 in (see FIG. 4) as a rotation shaft supported by interposing the main bearing 31 (42 ₁ to 42 _5), each crank journal 42 (42 ₁ to 42 ₅₎ the crank arm between 43
eccentric shaft crank pin 44 (4
4 _{1 to} 444 ₄ ). Crank arms 43a, 4
Balance weights 45a, 4 are provided on the opposite side of 3b, respectively.
5b is integrally formed.

[0026] Then, one end portion (right side in the figure) is a boss 46 for mounting the flywheel on the outer side of the crank journal 42 ₅ is formed. Further, (left side in the figure) and the other end portion on the outside of the crank journal 42 ₁ of the mounting portion 4 for mounting the pulley (not shown) which mounted a timing belt for driving the camshaft
7 and a mounting portion 48 for mounting a clamp pulley on which a belt for driving an auxiliary machine such as a fan is mounted.

Further, each crank pin 44 (44 _{1 to} 44)
The connecting rod bearing 21 (first and second connecting rod metal halves 21a, 21b) described above is attached to ₄ ), and the connecting rod bearing 21 is provided with a big end 49a at one end of the connecting rod 49 and a bearing cap (not shown). (Refer to FIG. 5) to fasten and closely fix. A small end 49b is formed at the other end of the connecting rod 49, the bush 50 is press-fitted into the small end 49b, and the piston 52 is attached via the piston pin 51.

Although FIG. 2 shows a case where the connecting rod 49 is attached only to the crank pin 44 ₄ , the connecting rods 21 are similarly interposed between the other crank pins 44 _{1 to} 44 ₃ to connect the connecting rod 49. 49 is attached.

Further, each crank journal 42 (42 ₂
To 42 ₄ The), above the main bearings 31 (first and second main metal half 31a, 31b) are mounted respectively on axially opposite sides with the crank washer 35a of the main bearing 31, 35b (washer half Body 35
a ₁ , 35a ₂ , 35b ₁ , 35b ₂ ) are attached respectively.

The crank washers 35a, 35b
May be provided only on both axial sides of the main bearing 31 of the central main journal 42 ₃ . Here, FIG. 4 shows an explanatory view of mounting the main bearing of FIG. 4, an arm-shaped support portions 36 ₁ to 36 ₃ is formed in the crankcase 36 as the housing, the support portion 36 _{1-36 3} each first main metal half constituting the main bearing 31 on 31a is located. In this case, each of the first main metal halves 31a has a structure shown in FIG.
As shown in FIG.

Then, each first main metal half body 31a
The second main metal halves 31b are butted against each other, and the bearing caps 53 are fastened to the crankcase 36 with bolts 54, respectively,
The main bearing 31 is closely fixed.

As shown in FIG. 1C, when the half-divided connecting rod bearing 21 and the half-divided main bearing 31 are tightly fixed to each other by fastening the bearing caps in this manner. Since it is formed into a protruding arc shape with a predetermined R, it can be adhered at an intermediate position where a certain uniform surface on the end face is secured, peeling of the alloy layer and housings 23, 36 of the bearings. Therefore, it is possible to prevent the occurrence of floating from the above and poor adhesion.

In the above embodiment, the housing 23
First connecting rod metal half 21 located at (36)
a and the case where the end faces 21a ₁ and 31a ₁ of the crash height portion of the first main metal half body 31a are formed in a protruding arc shape are shown, but the end faces on the opposite side or the second end to be abutted
Even if the connecting rod half body 21b and the end surfaces 21b ₁ and 31b ₁ of the second main metal half body 31a are appropriately formed in a protruding arc shape, the same effect can be obtained.

[0034]

As described above, according to the present invention, by forming at least one end surface of the bearing halves that are butted and closely fixed to the housing in the shape of a projecting arc,
A certain degree of uniform surface is secured at the intermediate position of the end surface, and it is possible to prevent uneven deformation.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention.

FIG. 2 is a schematic diagram of a crankshaft in which the bearing of FIG. 1 is used.

FIG. 3 is a partial cross-sectional view of FIG.

FIG. 4 is an explanatory view of mounting the main bearing of FIG.

FIG. 5 is a configuration diagram of a connecting rod attached to a conventional crankshaft.

FIG. 6 is an explanatory view of fixing the half bearing of FIG.

[Explanation of symbols]

21 connecting rod bearing 21a first connecting rod metal body 21b second connecting rod metal body 21a _1, 21b ₁ facet 31 main bearing 31a first main metal body 31b second main metal body 35a, 35b crank washer 41 crankshaft 42 crank Journal 43a, 43b Crank arm 44 Crank pin 45a, 45b Balance weight 49 Mounting part 49a Big end 49b Small end 52 Piston 53 Bearing cap

Claims (1)

[Claims] 1. A crush height in which bearing halves divided into halves are butted against each other and closely fixed to a housing, and one of the bearing halves protrudes from the fitted housing. In the bearing device having at least one of the bearing halves, at least one end face of the bearing halves to be butted is formed in a protruding arc shape.