WO2021152880A1

WO2021152880A1 - Bearing metal for engine

Info

Publication number: WO2021152880A1
Application number: PCT/JP2020/024674
Authority: WO
Inventors: 伸朗佐藤; 剛門脇
Original assignee: 三菱重工エンジン＆ターボチャージャ株式会社
Priority date: 2020-01-31
Filing date: 2020-06-23
Publication date: 2021-08-05
Also published as: JP2021124124A; JP7471097B2

Abstract

This bearing metal is for supporting a shaft, such as a piston pin, that is installed in a through hole formed in, for example, a small end portion of a connecting rod such that the connecting rod can pivot about the shaft. The bearing metal comprises a body that is installed on an internal circumferential surface of the through hole and a sliding surface that is formed on an inner circumference of the body and configured to be slidable with respect to the shaft. A flexible support section is formed in at least a portion of the interior of the body, the flexible support section having a lower rigidity than surrounding portions and supporting both end portions of the sliding surface in an elastically deformable manner.

Description

Bearing metal for engine

The present disclosure relates to bearing metals for engines, and in particular, bearing metals that support piston pins, crank pins, crank journals, etc. provided in engines.

The engine body (engine frame) has a through hole in which the crankshaft is installed. A bearing metal (plain bearing) is installed on the inner peripheral surface of the through hole, and the crank journal (main journal) constituting the crankshaft is slidably supported by the bearing metal installed in the through hole. .. On the other hand, through holes for installing bearing metal are also formed on the inner peripheral surfaces of the small end and the large end of the connecting rod (connecting rod). The large end of the connecting rod is connected to the crankshaft by installing the crankpins constituting the crankshaft in the through holes of the large end via the bearing metal. Further, the small end portion of the connecting rod is attached to the piston by a piston pin via a bearing metal installed on the inner peripheral surface of the through hole of the small end portion. The various shafts of the engine, such as the crank journal, crank pin, and piston pin described above, have relatively low bending rigidity in the recent trend of weight reduction and high output of the engine. For this reason, it becomes easy to bend due to the load acting when the engine is driven, so that there is a region at the end of the bearing metal where the oil film pressure becomes locally high or the oil film thickness becomes thin locally. One-sided contact is likely to occur. Then, this one-sided contact causes wear and seizure of the bearing, and hinders further weight reduction and high output of the engine.

For example, Patent Document 1 discloses that crowning is formed at axial ends (both ends) of a sliding surface (sliding contact surface) of a bearing metal (sliding bearing) that pivotally supports a crankshaft. Further, Patent Document 2 discloses that the sliding surface on which the small end and the piston pin slide is coated with a fluororesin as an elastic lubricant to prevent the piston from tilting in the cylinder. .. Patent Document 3 discloses that the amount of lubricating oil is increased and seizure at a small end portion is prevented by providing a plurality of recesses in a specific region of the inner peripheral surface of the pin hole. Patent Document 4 discloses that by forming a three-dimensional network structure (lattice structure) on the wall surface of a small end portion, heat dissipation is improved and oil is retained by increasing the surface area. In addition, Patent Document 5 discloses a part having the above-mentioned lattice structure.

International Publication No. 2008/072548 Japanese Unexamined Patent Publication No. 2007-40137 JP-A-2018-9634 JP-A-2018-168895 Japanese Unexamined Patent Publication No. 2015-93461

For example, as in Patent Document 1, in order to prevent one-sided contact of the shaft that may occur at the end of the bearing metal (bearing) when supporting various shafts such as a crank journal, a crank pin, and a piston pin. , It is conceivable to crank or taper the ends (both ends) of the bearing metal. However, since the area of the parallel portion (the portion other than the processed portion) in the bearing metal is reduced by the processed area, the bearing surface pressure may increase, which may contribute to fatigue failure of the bearing metal. In addition, when the amount of deformation on the shaft side is not constant, such as in the case of an engine operated with various loads, in the method of performing processing such as crowning in advance, the above-mentioned one-sided contact is made according to the loads of various engines. It is difficult to prevent properly.

It is also conceivable to make the lower side of the bearing metal (member for forming the through hole) a thin-walled structure or a notched structure to make it a flexible structure, but due to restrictions on stress concentration in the thin-walled part and the notched part, the target softness It may be difficult to achieve the structure. Alternatively, it is also conceivable to make the back surface (main body portion) of the sliding surface of the bearing metal with respect to the shaft a notched structure to form a flexible structure. However, the stable installation caused by the decrease in the effective area of the sliding surface due to the notch bending back when the bearing metal is fitted into the through hole, and the decrease in the contact area between the bearing metal and the member forming the through hole. There are concerns about a decrease in degree and the occurrence of fretting on the contact surface due to this decrease in stability.

In view of the above circumstances, at least one embodiment of the present invention provides a bearing metal capable of preventing one-sided contact at an end when supporting a shaft such as a piston pin, a crank pin, or a crank journal. The purpose.

The engine bearing metal according to at least one embodiment of the present invention is
A bearing metal for swingably supporting the connecting rod with respect to a shaft which is a piston pin installed in a through hole formed at a small end of the connecting rod.
The main body installed on the inner peripheral surface of the through hole and
A sliding surface formed on the inner peripheral side of the main body portion and configured to be slidable with respect to the shaft is provided.
At least a part of the inside of the main body is formed with a flexible support portion that elastically deformably supports both end sides of the sliding surface by having a rigidity lower than that of the surrounding portion.

The engine bearing metal according to at least one embodiment of the present invention is
A bearing metal for rotatably supporting a shaft, which is a crank pin of a crankshaft installed in a through hole formed at the large end of a connecting rod.
The main body installed on the inner peripheral surface of the through hole and
A sliding surface formed on the inner peripheral side of the main body portion and configured to be slidable with respect to the shaft is provided.
At least a part of the inside of the main body is formed with a flexible support portion that elastically deformably supports both end sides of the sliding surface by having a rigidity lower than that of the surrounding portion.

The engine bearing metal according to at least one embodiment of the present invention is
It is a bearing metal for rotatably supporting the shaft, which is the crank journal of the crankshaft installed in the through hole formed in the engine body.
The main body installed on the inner peripheral surface of the through hole and
A sliding surface formed on the inner peripheral side of the main body portion and configured to be slidable with respect to the shaft is provided.
A flexible support portion is formed in at least a part of the inside of the main body portion to elastically and deformably support at least one end side of the sliding surface by having a rigidity lower than that of the surrounding portion. ..

According to at least one embodiment of the present invention, there is provided a bearing metal capable of preventing one-sided contact at an end when supporting a shaft such as a piston pin, a crank pin, or a crank journal.

It is a figure which shows typically the front view of the connecting rod which concerns on one Embodiment of this invention. It is a figure which shows typically the cross section in the side view of the connecting rod which concerns on one Embodiment of this invention, and corresponds to the AA cross section of FIG. It is a figure which shows typically the crankshaft of the state which is supported by the engine body which concerns on one Embodiment of this invention. It is a figure which shows typically the cross section of the small end part which concerns on one Embodiment of this invention. It is a figure which shows typically the cross section of the small end part which concerns on another Embodiment of this invention. It is a figure which shows typically the cross section of the small end part which concerns on another embodiment of this invention. It is a figure which shows typically the front view of the small end part which concerns on one Embodiment of this invention. It is a figure which shows typically the front view of the small end part which concerns on another Embodiment of this invention.

Hereinafter, some embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described as embodiments or shown in the drawings are not intended to limit the scope of the present invention to this, and are merely explanatory examples. do not have.

For example, expressions that represent relative or absolute arrangements such as "in a certain direction", "along a certain direction", "parallel", "orthogonal", "center", "concentric" or "coaxial" are exact. Not only does it represent such an arrangement, but it also represents a state of relative displacement with tolerances or angles and distances to the extent that the same function can be obtained.

For example, expressions such as "same", "equal", and "homogeneous" that indicate that things are in the same state not only represent exactly the same state, but also have tolerances or differences to the extent that the same function can be obtained. It shall also represent the existing state.

For example, an expression representing a shape such as a quadrangular shape or a cylindrical shape not only represents a shape such as a quadrangular shape or a cylindrical shape in a geometrically strict sense, but also an uneven portion or chamfering within a range in which the same effect can be obtained. The shape including the part and the like shall also be represented.

On the other hand, the expressions "equipped", "equipped", "equipped", "included", or "have" one component are not exclusive expressions that exclude the existence of other components.

FIG. 1 is a diagram schematically showing a front view of the connecting rod 5 according to the embodiment of the present invention. FIG. 2 is a diagram schematically showing a cross section of a connecting rod 5 according to an embodiment of the present invention, and corresponds to the AA cross section of FIG. FIG. 3 is a diagram schematically showing a crankshaft 9 in a state of being supported by the engine body E according to the embodiment of the present invention. 4 to 6 are diagrams schematically showing a cross section of a small end portion 7 according to an embodiment of the present invention according to an embodiment of the present invention, respectively. 7 to 8 are views schematically showing a front view of the small end portion 7 according to the embodiment of the present invention.

In the following, the axial direction of the connecting rod 5 (extending direction of the connecting rod 5s) is referred to as the rod axial direction Ds, and among the directions orthogonal to the rod axial direction Ds (radial direction), the extending direction of the following center line CL Is called the center line direction Dr. Further, a straight line (hereinafter, center line CL) passing through the cross-sectional center of the through hole T (FIGS. 4 to 6 are the piston pin hole 7t of the small end portion 7) as shown in FIGS. 4 to 6 and the center line CL. The case where the cross section of the connecting rod 5 including the straight line extending in the rod axial direction Ds and intersecting with the connecting rod 5 is visually recognized is referred to as a side cross-sectional view. Further, the case where the center line CL as shown in FIGS. 7 to 8 is visually recognized as a point is referred to as a front view. When the bearing metal 1 is installed in the through hole T, the center line CL of the through hole T coincides with the center line CL of the bearing metal 1.

The connecting rod (hereinafter referred to as the connecting rod 5) is a component for converting the reciprocating motion of the piston (not shown) included in the engine (internal combustion engine) into the rotational motion of the crankshaft 9. As shown in FIGS. 1 to 2, the connecting rod 5 has a large end portion 6, a small end portion 7, and a connecting rod 5s that connects the large end portion 6 and the small end portion 7. Then, the crankshaft 9 (see FIG. 3) is connected to the large end portion 6, and the piston pin 71 (see FIGS. 4 to 6) is connected to the small end portion 7, whereby the piston (not shown) and the crankshaft. 9 is connected by a connecting rod 5.

More specifically, as shown in FIG. 3, the crankshaft 9 has a crankpin 91 connected to a large end 6 of a connecting rod 5 and a crank journal 92 supported by an engine body E (engine frame) such as a cylinder block. And have. On the other hand, the engine body E is formed with a through hole T (main shaft hole Et) for attaching the crank journal 92. A sliding surface 3 is formed by installing (fitting) a bearing metal 1 (main bearing 1 m) on the inner peripheral surface of the spindle hole Et, and a crank journal 92 and a main bearing 1 m are installed. The crankshaft 9 is supported by the engine body E by being inserted into the spindle hole Et.

Then, as shown in FIGS. 1 to 2, a through hole T (crank pin hole 6t) for attaching the crank pin 91 is formed at the large end portion 6. A bearing metal 1 (crank pin bearing 1c) is installed (fitted) on the inner peripheral surface of the crank pin hole 6t, and a sliding surface 3 with respect to the crank pin 91 is formed. Then, the crank pin 91 is inserted into the crank pin hole 6t in which the crank pin bearing 1c is installed, so that the large end portion 6 and the crank pin 91 are slidably connected.

Similarly, as shown in FIGS. 1 to 2 and 4 to 8, a through hole T (piston pin hole 7t) for attaching the piston pin 71 is formed in the small end portion 7. A bearing metal 1 (piston pin bearing 1p) is installed (fitted) on the inner peripheral surface of the piston pin hole 7t, and a sliding surface 3 with respect to the piston pin 71 is formed. Then, the piston pin 71 connected (fixed) to the piston (not shown) is inserted into the piston pin hole 7t in which the piston pin bearing 1p is installed, so that the small end portion 7 and the piston (not shown) are connected to each other. It is slidably connected.

Here, the bearing metal 1 serving as the piston pin bearing 1p, the crank pin bearing 1c, the main bearing 1 m and the like described above includes the crank pin hole 6t (see FIG. 1) and the piston pin hole 7t (FIGS. 1 to 2). (See FIGS. 4 to 8), a main body 2 installed on the inner peripheral surface of various through holes T such as a spindle hole Et (see FIG. 3), and a piston formed on the inner peripheral side of the main body 2. It includes a sliding surface 3 that is slidable with respect to a shaft S such as a pin 71, a crank pin 91 (rotary shaft), or a crank journal 92 (rotary shaft).

Explaining the embodiments shown in FIGS. 1 to 8, various through holes T have a tubular shape having a perfect circular cross-sectional shape. Further, the engine is a multi-cylinder engine, and the crankshaft 9 has a plurality of crank pins 91 and a plurality of crank journals 92. It is also a V-type engine, and two connecting rods 5 connected to pistons (not shown) in each cylinder of each V-type bank are connected to each crank pin 91.

In the embodiments shown in FIGS. 1 to 8, the small end portion 7 and the connecting rod 5s are integrally manufactured (modeled), and the connecting rod 5s and the large end portion 6 are fastened with a bolt 5b. However, at least two of the large end portion 6, the small end portion 7, and the connecting rod 5s may be integrally manufactured.

In the bearing metal 1 having the above-described configuration, at least a part of the inside of the main body portion 2 has a rigidity lower than that of the peripheral portion, so that at least one end portion (center line direction Dr) of the sliding surface 3 is formed. A flexible support portion 4 is formed to elastically and deformably support the side (end portion) of the bearing.
Specifically, as shown in FIGS. 4 to 6, for the piston pin bearing 1p, the flexible support portions 4 may be formed on both end sides of the main body portion 2. Although not shown, the flexible support portions 4 may be formed on both end sides of the main body portion 2 in the crank pin bearing 1c as well. On the other hand, as shown in FIG. 3, for the main bearing 1 m, the flexible support portion 4 may be formed on at least one end side of the main body portion 2. That is, the flexible support portion 4 is provided on the portion of the main body portion 2 that supports the one-sided contact region of the shaft S on the sliding surface 3 of the bearing metal 1.

When the flexible support portion 4 is provided in a portion where one-sided contact of the shaft S is likely to occur in this way, the flexible support portion 4 is elastic in the direction of one-sided contact received by bending the shaft S, depending on the size of the one-sided contact. change. For example, in the side sectional view of the small end portion 7 shown in FIGS. 4 to 6, as shown in the drawing, both ends of the piston pin 71 are on the large end portion 6 side (below the paper surface) in the rod axial direction Ds like a chain line. When it is bent toward, the piston pin bearing 1p is deformed so that the illustrated cross-sectional area of the flexible support portion 4 is smaller than that when it is not bent. Then, when the piston pin 71 is no longer bent and the piston pin 71 returns to the linear state, the illustrated cross-sectional area of the flexible support portion 4 returns to the original size before bending. Although not shown, the crank pin bearing 1c (see FIG. 2) has the same bending method of the crank pin 91 and the deformation of the flexible support portion 4 as described above. As shown by the chain line in FIG. 3, the main bearing 1 m is elastically deformed as the crank journal 92 (chain line) bends.

Further, the sliding surface 3 is also elastically deformed due to the elastic deformation of the flexible support portion 4 described above. As a result, it is possible to suppress the occurrence of a region where the oil film pressure on the bearing metal 1 (sliding surface 3) is locally increased or the oil film thickness is locally thin due to one-sided contact of the shaft S. ..

In this way, the flexible support portion 4 is formed at the end portion of the bearing metal 1, and at this end portion, the flexible support portion 4 is at least one side or the other side of the rod axial direction Ds with respect to the center line CL described above. It may be provided on one side.
Specifically, with respect to the piston pin bearing 1p, as shown in FIG. 1, at least in the axial direction of the connecting rod 5 toward the large end side (lower side in FIG. 1) with respect to the center line CL of the piston pin hole 7t. It may be provided. Regarding the crank pin bearing 1c, as shown in FIG. 1, the large end side direction (lower side in FIG. 1) and the small end side direction (lower side in FIG. 1) in the axial direction of the connecting rod 5 from the center line CL of the piston pin hole 7t ( It may be provided in both directions (upper side of FIG. 1). As shown in FIG. 3, the main bearing 1 m may be provided at least on the lower side (lower side of FIG. 3) of the engine main body E than the center line CL of the main shaft hole Et. These positions are positions in which a large one-sided contact of the shaft S is likely to occur due to the combustion load of the fuel in the engine and the inertial force of the piston or connecting rod in some embodiments.

Further, as shown in FIGS. 1 and 7 to 8, in the front view, the flexible support portion 4 extends along the inner peripheral surface (circumferential direction of the bearing metal 1) of the sliding surface 3 of the bearing metal 1. It may be provided so as to do so. In the present embodiment, in the front view of the flexible support portion 4, the portion having the highest bearing load acting on the bearing metal 1 is located near the center of the flexible support portion 4, and from there to the inner peripheral surface of the sliding surface 3. It is provided so as to extend to the left and right along it. This makes it possible to provide the flexible support portion 4 so as to cover the portion of the various shafts S having a large one-sided contact.

On the other hand, the rigidity of the flexible support portion 4 is the rigidity per unit volume. The smaller the rigidity, the larger the amount of deformation for the same load, and conversely, the larger the rigidity, the smaller the amount of deformation for the same load. In the embodiment shown in FIGS. 1 to 8, the flexible support portion 4 is configured to elastically and deformably support the sliding surface 3 of the bearing metal 1 by having a lattice (porous) structure. This lattice structure is a grid-like (mesh-like) structure, and a cavity portion is formed between the portions (connecting portions) connecting the lattice points. Then, the rigidity of the flexible support portion 4 can be arbitrarily adjusted by the volume ratio (roughness) of the hollow portion, and the rigidity of the flexible support portion 4 differs depending on this adjustment. Therefore, by providing the lattice structure at an appropriate portion of the main body 2, the end side of the sliding surface 3 of the bearing metal 1 is elastic according to the size of one side of the shaft S (the size of the bearing load). It can be made possible to bend in a targeted manner.

The flexible support portion 4 may be integrally molded with the main body portion 2 by a three-dimensional modeling device such as a 3D printer. The portion of the main body 2 other than the soft support portion 4 is shaped so as to have a structure different from that of the soft support portion 4, and is shaped to have higher rigidity than the soft support portion 4. For example, the flexible support portion 4 is shaped so as to have a lattice structure, and the portion of the main body portion 2 other than the flexible support portion 4 is formed by simply laminating uniform layers of modeling materials in order, which is more than the lattice structure. It is shaped so that it has high rigidity.

However, the present invention is not limited to the present embodiment. In the embodiments shown in FIGS. 1 to 8, the flexible support portion 4 is provided on the inner side of the outer peripheral surface of the main body portion 2, but in some other embodiments, the flexible support portion 4 is the main body portion 2. It may extend to the outer peripheral surface of. Further, in some other embodiments, the flexible support portion 4 may be provided in a straight line in a front view. Further, the flexible support portion 4 may have a hollow portion, and its structure is not limited to the lattice structure. For example, in some other embodiments, the flexible support portion 4 may have a thin wall structure or a notched structure. Further, the rigidity of the flexible support portion 4 may be adjusted by forming the flexible support portion 4 into a thin-walled structure or a notched structure and then installing or fitting another member having low rigidity.

Further, since the one-sided contact of the shaft S acting on various bearing metals 1 (sliding surface 3) can change depending on the operating conditions of the engine, the rotation direction and configuration of the crankshaft 9, etc., the flexible support in the main body 2 The position of the portion 4 may be provided at an arbitrary position on the end side of the bearing metal 1. For example, in the embodiment shown in FIG. 3, the flexible support portion 4 of the main bearing 1 m is provided only on the lower side where the one-sided contact of the shaft S with respect to the bearing metal 1 is larger, but it may be provided on the upper side. For example, the chain line showing the crank journal 92 is shown in FIG. 3 in a case where the lower left of the paper is tilted downward and the upper right is upward, but the lower left is upward and the upper right is downward. In some cases, it may bend in the opposite direction. As described above, the bending method of the axis S is not limited to the bending shown in FIGS. 4 to 6.

According to the above configuration, the main body 2 of the bearing metal 1 is formed with a flexible support 4 for elastically deformably supporting both end sides of the sliding surface 3. When the shaft S (piston pin 71, crank pin 91 or crank journal 92) is bent by the flexible support portion 4, the end side of the sliding surface 3 of the bearing metal 1 can also be bent in the bending direction of the shaft S. , It is possible to prevent one side of the shaft S from hitting the end of the bearing metal 1. Therefore, it is possible to prevent wear and seizure of the bearing metal 1, and it is possible to further reduce the weight and increase the output of the engine.

Next, the position where the above-mentioned flexible support portion 4 is provided will be described in more detail with reference to FIGS. 4 to 8. The small end portion 7 will be described as an example, but the same applies to the flexible support portion 4 of the crank pin bearing 1c and the flexible support portion 4 of the main bearing 1 m. Further, in the following, the position of the center of the bearing metal 1 in the direction of the center line is referred to as the bearing metal center C. The bearing metal center C is the position of the center of the bearing metal 1 in the side sectional view shown in FIGS. 2 and 4 to 6, and is a line connecting the center lines CL of the large end portion 6 and the small end portion 7. It is also the position where The central position of the flexible support portion 4 in front view is called the front central position Cb.

In some embodiments, as shown in FIGS. 4 to 8, the flexible support portion 4 is formed on the end side of the bearing metal center C in the main body portion 2. In the embodiment shown in FIGS. 4 to 8, for example, as shown in FIG. 4, in the side sectional view, the flexible support portion 4 is directed from the end of the main body portion 2 toward the bearing metal center C side in the center line direction Dr. Along the way, it is provided up to a predetermined distance (depth width W). More specifically, if the distance between the end of the main body 2 and the center C of the bearing metal along the center line direction Dr is Wa, W <Wa.

This depth width W may be determined according to the assumed degree of bending of the axis S. Further, it may be determined in consideration of the rigidity of the shaft S and the rigidity of the member for forming the through hole T (small end portion 7 in FIGS. 4 to 6) that supports the main body portion 2. Further, the depth width W may be the same or different at a position along the circumferential direction of the connecting rod 5s. The depth width W may be made different along the above-mentioned circumferential direction, for example, the depth width W may be made smaller toward the end side of the sliding surface 3 in the front view. By changing the depth width W in the circumferential direction, it is possible to adjust the rigidity of the flexible support portion 4.

According to the above configuration, the flexible support portion 4 is provided only on the end side of the center of the bearing metal 1. As a result, it is possible to appropriately prevent one-sided contact of the shaft S while maintaining the rigidity of the bearing metal 1 appropriately.

Next, some embodiments relating to the above-mentioned flexible support portion 4 will be described.
In some embodiments, as shown in FIGS. 4 to 8 (the same applies to FIGS. 1 and 3), at the end of the flexible support portion 4 (the end on the center C side of the bearing metal, the end in the circumferential direction). May be provided with Earl R. In the embodiment shown in FIGS. 4 to 6, in the side sectional view, a radius R is attached to the end portion of the flexible support portion 4 on the center C side of the bearing metal. In other words, in the side sectional view, the length (height width H) along the rod axial direction Ds at the end of the flexible support portion 4 on the bearing metal center C side is continuous toward the bearing metal center C side. It has been shortened by changing it to. In the embodiment shown in FIGS. 7 to 8, R-Rs are provided at both ends of the flexible support portion 4 in the front view.
According to the above configuration, stress concentration at the end portion of the flexible support portion 4 can be suppressed.

Further, in some embodiments, as shown in FIGS. 4 to 6, the rigidity of the bearing metal 1 is not the same along the center line direction Dr in the portion where the flexible support portion 4 is present, but changes. It may be configured to have at least a portion. As a result, the amount of deformation of the flexible support portion 4 when the engine is driven can be made larger on the end side of the bearing metal 1 than on the center side of the bearing metal. The moving surface 3 can be easily bent.

Specifically, in some embodiments, as shown in FIGS. 4 to 5, an arbitrary portion of the flexible support portion 4 in the side sectional view is referred to as a first portion Pa, and is more than the first portion Pa. When the portion located on the end side of the bearing metal 1 in the center line direction Dr is referred to as the second portion Pb (the same applies hereinafter), the rigidity of the second portion Pb is lower than the rigidity of the first portion Pa. That is, the rigidity of the flexible support portion 4 is adjusted along the center line direction Dr, and the rigidity of the flexible support portion 4 is adjusted from the small region of the shaft S to the one-sided size (bearing load size) of the shaft S. The rigidity of each part of the flexible support portion 4 is reduced toward the region. As a result, the flexible support portion 4 is made so that the portion on the end side of the bearing metal 1 in the center line direction Dr is relatively more easily elastically deformed than the portion on the center C side of the bearing metal. Is possible.

For example, when the flexible support portion 4 is formed with a lattice structure, the magnitude of rigidity can be changed by changing the density of the cavity formed by the lattice structure. At this time, if the density of the cavity in the direction of the height width H of the flexible support portion 4 (rod axial direction Ds) is the same, for example, the longer the height width H of the flexible support portion 4, the softer the flexible support in the main body portion 2. Since the proportion of the portion 4 is increased and the rigidity of the portion (main body portion 2) is reduced, the sliding surface 3 of the bearing metal 1 is easily elastically deformed with respect to the same load.

More specifically, the size of the unit lattice may be changed while the structure of the unit lattice forming the lattice structure is the same for the first portion Pa and the second portion Pb. In other words, when comparing the lengths of the corresponding connecting portions of the unit cell, the second portion Pb is longer than the first portion Pa. In this way, if the lattice size of the second portion Pb is made larger than the lattice size of the first portion Pa, the volume occupied by the cavity formed inside the lattice structure is the volume occupied by the second portion Pb per unit volume. Is larger than the first portion Pa, and the cavity portion of the second portion Pb can be provided more sparsely than the cavity portion of the first portion. Alternatively, the structure of the unit cell of the second portion Pb may have a larger cavity than the structure of the unit cell of the first portion Pa. The larger the volume of the cavity (the sparser the cavity), the smaller the rigidity of that portion.

In the embodiment shown in FIG. 4, the density of the cavity is changed from the center C side of the bearing metal toward the end side of the bearing metal 1 along the center line direction Dr, and the soft support portion is formed. The length (height width H) in the rod axial direction Ds in No. 4 is substantially the same along the center line direction Dr except for the end portion with the radius R.

On the other hand, in the embodiment shown in FIG. 5, similarly, the density of the cavity is changed from the center C side of the bearing metal toward the end side of the bearing metal 1 along the center line direction Dr. At the same time, the height width H of the flexible support portion 4 increases toward the center C side of the bearing metal along the center line direction Dr. As shown in FIG. 5, the desired rigidity can be set (secured) by simultaneously adjusting the density of the cavity portion in the flexible support portion 4 and the height width H (thickness). In particular, by making the height width H of the flexible support portion 4 larger at the end portion on the bearing metal center C side as shown in FIG. 5, the end portion of the flexible support portion 4 on the bearing metal center side as described above is formed. When the radius R is provided in the bearing, it is possible to set the rigidity of the flexible support portion 4 in the center line direction Dr while ensuring the size as a target.

In some other embodiments, as shown in FIG. 6, the rigidity of the second portion Pb is equal to the rigidity of the first portion Pa. In the embodiment shown in FIG. 6, the flexible support portion 4 has a lattice structure, but the unit lattice forming the first portion Pa and the second portion Pb has the same structure, so that the first portion Pa and the first portion Pa and the second portion Pb have the same structure. The rigidity of the second portion Pb may be equal.

Here, in order to increase the amount of elastic deformation of the flexible support portion 4 with respect to the same load at each position along the center line direction Dr from the small region to the large region of the shaft S. It is necessary to adjust the height width H of the flexible support portion 4 along the center line direction Dr. In the present embodiment, since the rigidity of the first portion Pa and the second portion Pb are equal, the longer the height width H of the flexible support portion 4, the elastically deforms the sliding surface 3 of the bearing metal 1 with respect to the same load. It will be easier. Therefore, in the embodiment shown in FIG. 6, the height width Hb at the position of the second portion Pb is longer than the height width Ha at the position of the first portion Pa (Hb> Ha).

According to the above configuration, the bearing metal 1 is configured so that its rigidity is not the same along the center line direction Dr in the portion where the flexible support portion 4 is present, but has at least a portion that changes. There is. As a result, the amount of deformation of the flexible support portion 4 when the engine is driven can be appropriately set along the center line direction Dr according to the size of one side of the shaft S.
However, the present invention is not limited to this embodiment, and in some other embodiments, the rigidity of the flexible support portion 4 may be the same at an arbitrary rigidity value in almost all parts.

Further, in some embodiments, as shown in FIGS. 7 to 8, the rigidity of the bearing metal 1 is not the same along the circumferential direction of the bearing metal 1 in the portion where the flexible support portion 4 is present. It may be configured to have at least a portion that changes. As a result, the amount of deformation of the flexible support portion 4 when the engine is driven is located on the center (front center position Cb) side of the flexible support portion 4 in front view, and is located on both end sides. It can be made larger than the portion with respect to the same load, and the portion located on the center side makes it possible for the sliding surface 3 to bend more easily.

Here, when visually recognized from the front, for example, in the case of the piston pin bearing 1p, the one-sided contact of the shaft S acting on the bearing metal 1 from the shaft S (piston pin 71) is from the center line CL to the longitudinal direction of the connecting rod 5. The vicinity of the portion of the bearing metal 1 through which the line drawn along (rod axial direction Ds) passes (the front center position Cb of the flexible support portion 4 in FIGS. 7 to 8) is the largest, and from there to both sides of the sliding surface 3. It gets smaller as you go. Although not shown, in the crank pin bearing 1c and the main bearing 1 m, the position of one side of the shaft S is different from that of the piston pin bearing 1p, but it becomes smaller from the largest portion toward both sides in the circumferential direction. Therefore, as shown in FIGS. 1 to 8, the flexible support portion 4 is provided so that the front center position Cb of the flexible support portion 4 overlaps the portion where the one-side contact of the various bearing metals 1 is highest, and then the piece of the shaft S. By increasing the rigidity of the end portion of the flexible support portion 4, which is a small hit portion, to the rigidity of the front center position Cb, which is a large portion, the rigidity is brought closer to the rigidity when the flexible support portion 4 is not provided. ..

Specifically, in some embodiments, as shown in FIG. 7, an arbitrary portion of the flexible support portion 4 in front view is referred to as a third portion Pc, and the sliding surface 3 has a sliding surface 3 rather than the third portion Pc. When the portion located on the end side is referred to as the fourth portion Pd (the same applies hereinafter), the rigidity of the fourth portion Pd is higher than the rigidity of the third portion Pc. For example, the magnitude of the rigidity may be changed by changing the density of the cavity formed by the lattice structure. As a result, the flexible support portion 4 is more likely to be elastically deformed on the inner side. Thereby, the rigidity of the flexible support portion 4 in the above-mentioned front view can be appropriately set.

In the embodiment shown in FIG. 7, the front center position Cb of the flexible support portion 4 is aligned with the portion where the load acting on the bearing metal 1 is highest in the front view (for example, FIG. 7), and the above rigidity relationship is satisfied. The flexible support portion 4 is configured. As a result, as shown in FIG. 7, even if the thickness of the flexible support portion 4 (height width H described above) is the same, the flexible support portion 4 is located on the front center position Cb side of the flexible support portion 4 in the bearing metal 1. The part can be made easier to bend. As a result, the larger the one-sided contact of the shaft S with the bearing metal 1, the easier it is for the bearing metal 1 to bend in accordance with the one-sided contact of the shaft S.

In some other embodiments, as shown in FIG. 8, the rigidity of the fourth portion Pd is equal to the rigidity of the third portion Pc. In this case, the longer the height and width H of the flexible support portion 4, the more easily the bearing metal 1 is elastically deformed with respect to the same load. Therefore, as shown in FIG. 8, the height width H at the position of the fourth portion Pd is longer than the height width H at the position of the third portion Pc. Further, in the embodiment shown in FIG. 8, the flexible support portion 4 has a lattice structure, but the unit lattice forming the third portion Pc and the fourth portion Pd has the same structure, so that the third portion The rigidity of Pc and the fourth portion Pd may be equal. Thereby, the rigidity of the flexible support portion 4 in the above-mentioned front view can be appropriately set.

In the embodiment shown in FIG. 8, the portion where the load acting on the bearing metal 1 is highest at the front center position Cb of the flexible support portion 4 extending along the circumferential direction of the bearing metal 1 in the front view (for example, FIG. 8). The flexible support portion 4 is configured so as to satisfy the above-mentioned rigidity relationship. As a result, as shown in FIG. 8, the thickness of the flexible support portion 4 (height width H described above) is positioned closer to the front center position Cb side than the portion located on the end portion side (fourth portion Pd). By making the portion (third portion Pc) larger, the portion (third portion Pc) located on the front center position Cb side of the flexible support portion 4 in the bearing metal 1 can be bent more easily. As a result, the larger the one-sided contact of the shaft S with the bearing metal 1, the easier it is for the bearing metal 1 to bend in accordance with the one-sided contact of the shaft S.

According to the above configuration, the bearing metal 1 has a portion in which the rigidity thereof is not the same along the circumferential direction of the bearing metal 1 in the portion where the flexible support portion 4 exists, but at least a part thereof changes. As a result, the amount of deformation of the flexible support portion 4 when the engine is driven can be appropriately set along the center line direction Dr according to the size of one side of the shaft S.

The present invention is not limited to the above-described embodiment, and includes a modified form of the above-described embodiment and a combination of these embodiments as appropriate.
(Additional note)

(1) The engine bearing metal (1) according to at least one embodiment of the present invention is
A bearing metal (1) for swingably supporting a shaft (S), which is a piston pin (71) installed in a through hole (T) formed in a small end (7) of a connecting rod (5). There,
The main body (2) installed on the inner peripheral surface of the through hole (T) and
A sliding surface (3) formed on the inner peripheral side of the main body (2) and configured to be slidable with respect to the shaft (S) is provided.
A flexible support portion that elastically deformably supports both end sides of the sliding surface (3) by having at least a part of the inside of the main body portion (2) having a rigidity lower than that of the surrounding portion. (4) is formed.

According to the configuration of the above (1), the main body portion (2) of the bearing metal (1) installed in the through hole (T) formed in the small end portion (7) of the connecting rod (5) has its structure. A flexible support portion (4) for elastically deformably supporting both end sides of the sliding surface (3) (bearing metal (1)) is formed. As a result, when the piston pin (71) (shaft (S)) slidably supported by the bearing metal (1) is bent, the sliding surface (1) of the bearing metal (1) is bent in the bending direction of the piston pin (71). Since the end side of 3) can also be bent, it is possible to prevent the piston pin (71) from hitting the end of the bearing metal (1). Therefore, it is possible to prevent wear and seizure of the bearing metal (1), and it is possible to further reduce the weight and increase the output of the engine.

(2) In some embodiments, in the configuration of (1) above,
The flexible support portion (4) is provided in the direction toward the large end portion (6) in the axial direction of the connecting rod (5) with respect to the center line passing through the center of the cross section of the through hole (T).

According to the configuration of (2) above, the flexible support portion (4) is a piston pin (2) in the main body portion (2) of the bearing metal (1) installed in the through hole (T) of the small end portion (7). It is provided in a portion where one-sided contact is likely to occur, such as a portion where one-sided contact is large in 71). The one-sided contact of the shaft is larger on the connecting rod (5s) side in the through hole (T) of the small end portion (7) than on the opposite side. As a result, it is possible to prevent the piston pin (71) from hitting one end of the bearing metal (1).

(3) The engine bearing metal (1) according to at least one embodiment of the present invention is
A bearing for rotatably supporting a shaft (S) which is a crank pin (91) of a crankshaft (9) installed in a through hole (T) formed in a large end (6) of a connecting rod (5). Metal (1)
The main body (2) installed on the inner peripheral surface of the through hole (T) and
A sliding surface (3) formed on the inner peripheral side of the main body (2) and configured to be slidable with respect to the shaft (S) is provided.
A flexible support portion that elastically deformably supports both end sides of the sliding surface (3) by having at least a part of the inside of the main body portion (2) having a rigidity lower than that of the surrounding portion. (4) is formed.

According to the configuration of (3) above, the main body portion (2) of the bearing metal (1) installed in the through hole (T) formed in the large end portion (6) of the connecting rod (5) has its structure. A flexible support portion (4) for elastically deformably supporting both end sides of the sliding surface (3) is formed. As a result, when the crank pin (91) (shaft (S)) slidably supported by the bearing metal (1) is bent, the sliding surface (1) of the bearing metal (1) is bent in the bending direction of the crank pin (91). Since the end side of 3) can also be bent, it is possible to prevent the crank pin (91) from hitting the end of the bearing metal (1). Therefore, it is possible to prevent wear and seizure of the bearing metal (1), and it is possible to further reduce the weight and increase the output of the engine.

(4) In some embodiments, in the configuration of (3) above,
The flexible support portion (4) is closer to the large end portion (6) side and the small end portion (7) side in the axial direction of the connecting rod (5) than the center line passing through the center of the cross section of the through hole (T). It is provided in both directions.

According to the configuration of (4) above, the flexible support portion (4) is a crank pin (2) in the main body portion (2) of the bearing metal (1) installed in the through hole (T) of the large end portion (6). It is provided in a portion where one-sided contact is likely to occur, such as a portion where one-sided contact is large in 91). This makes it possible to prevent the crank pin (91) from hitting one end of the bearing metal (1).

(5) The engine bearing metal (1) according to at least one embodiment of the present invention is
A bearing metal (1) for rotatably supporting a shaft (S) which is a crank journal of a crankshaft (9) installed in a through hole (T) formed in an engine body.
The main body (2) installed on the inner peripheral surface of the through hole (T) and
A sliding surface (3) formed on the inner peripheral side of the main body (2) and configured to be slidable with respect to the shaft (S) is provided.
A flexible support that elastically deformably supports at least one end side of the sliding surface (3) by having at least a part of the inside of the main body portion (2) having a rigidity lower than that of the surrounding portion. The part (4) is formed.

According to the configuration of (5) above, the bearing metal installed in the through hole (T) formed in the engine body (engine frame) such as the cylinder block through which the crank journal constituting the crankshaft (9) is inserted. A flexible support portion (4) for elastically deformably supporting both end sides of the sliding surface (3) is formed on the main body portion (2) of the (1). As a result, when the crank journal (shaft (S)) slidably supported by the bearing metal (1) is bent, the sliding surface (3) of the bearing metal (1) is bent in the bending direction of the crank journal (92). Since the end side can also be bent, it is possible to prevent the crank journal (92) from hitting the end of the bearing metal (1). Therefore, it is possible to prevent wear and seizure of the bearing metal (1), and it is possible to further reduce the weight and increase the output of the engine.

(6) In some embodiments, in the configuration of (5) above,
The flexible support portion (4) is provided below the engine main body with respect to the center line passing through the center of the cross section of the through hole (T).

According to the configuration of (6) above, the flexible support portion (4) is a piece of the crank journal (92) in the main body portion (2) of the bearing metal (1) installed in the through hole (T) of the engine main body. It is provided in a part where one-sided contact is likely to occur, such as a part where the hit is large. This makes it possible to prevent the crank pin (91) from hitting one end of the bearing metal (1).

(7) In some embodiments, in the configurations (1) to (6) above,
The flexible support portion (4) is formed on the end side of the main body portion (2) with respect to the center.

According to the configuration of (7) above, the flexible support portion (4) is provided only on the end side of the center of the bearing metal (1). As a result, it is possible to appropriately prevent one-sided contact of the shaft (S) while maintaining the rigidity of the bearing metal (1) appropriately.

(8) In some embodiments, in the configuration of (7) above,
The flexible support portions (4) are arranged on a first portion aligned with each other along a center line passing through the center of the cross section of the bearing metal (1), and on the end side of the sliding surface (3) with respect to the first portion. Including the second part located
The rigidity of the second portion is lower than the rigidity of the first portion.

According to the configuration of (8) above, the rigidity of the flexible support portion (4) is toward the portion located at the end of the bearing metal (1) along the extending direction of the center line of the bearing metal (1). Is smaller than the central part. As a result, even if the thickness (height width) of the flexible support portion (4) along the extending direction of the center line is the same, the bearing metal (1) is placed closer to the end side. It can be configured to be easy to bend. Therefore, it is possible to more appropriately prevent one-sided contact of the shaft (S) with the end portion of the bearing metal (1).

(9) In some embodiments, in the configuration of (7) above,
The flexible support portions (4) are arranged on a first portion aligned with each other along a center line passing through the center of the cross section of the bearing metal (1), and on the end side of the sliding surface (3) with respect to the first portion. Including the second part located
The rigidity of the second portion is equal to the rigidity of the first portion.

According to the configuration of (9) above, the rigidity of the flexible support portion (4) is set to be equal along the extending direction of the center line of the bearing metal (1). As a result, by changing the thickness (height width) of the flexible support portion (4), the sliding surface (3) of the bearing metal (1) becomes an end in the extending direction of the center line. The part closer to the part can be bent more easily. Therefore, it is possible to more appropriately prevent the shaft (S) from hitting the end of the bearing metal (1).

(10) In some embodiments, in the configurations (8) to (9) above,
The amount of deformation of the bearing metal (1) when the engine is driven is configured to increase toward the end side of the sliding surface (3) along the center line.

According to the configuration of the above (10), in the bearing metal (1), the portion on the outer side in the radial direction of the connecting rod (5) in the side sectional view can be easily bent, and the end of the bearing metal (1) can be easily bent. It is possible to more appropriately prevent one-sided contact of the shaft (S) with the portion.

(11) In some embodiments, in the configurations (1) to (10) above,
The flexible support portion (4) extends along the sliding surface (3) in a front view (for example, FIGS. 7 to 8) visually recognized along a center line passing through the center of the cross section of the through hole (T). It is provided to be present.
According to the configuration of (11) above, the flexible support portion (4) can be provided so as to cover the portion of the shaft (S) having a large one-sided contact.

(12) In some embodiments, in the configuration of (11) above,
The flexible support portion (4) has a third portion (Pc) and a third portion (Pc) in a front view (for example, FIG. 7) in which the bearing metal (1) is visually recognized along the extending direction of the center line. Including the fourth part (Pd) located on the end side of Pc),
The rigidity of the fourth portion (Pd) is higher than the rigidity of the third portion (Pc).

According to the configuration of the above (12), in the above front view (for example, FIG. 7), the rigidity of the flexible support portion (4) is higher in the end side portion (Pd) than in this portion (Pd). Is also higher than the part (Pc) located on the central side. The load acting on the bearing metal (1) due to one-sided contact decreases from the portion having the largest one-sided contact toward both sides of the bearing metal (1) in the circumferential direction. As a result, even if the thickness of the flexible support portion (4) (the above height width (H)) is the same, the central portion of the flexible support portion (4) in the bearing metal (1) is positioned. The more you bend, the easier it is to bend. Therefore, for example, in the front view (for example, FIG. 7), the center (front center position) of the flexible support portion (4) extending along the circumferential direction of the bearing metal (1) is set to the axis (S) with respect to the bearing metal (1). If the flexible support portion (4) is configured so as to satisfy the above-mentioned rigidity relationship while adjusting to the portion having the largest one-sided contact with the bearing metal (1), the larger the one-sided contact of the shaft (S) with the bearing metal (1), the larger the portion. , The bearing metal (1) can be easily bent according to the one-sided contact of the shaft (S).

(13) In some embodiments, in the configuration of (11) above,
The flexible support portion (4) has a third portion (Pc) and a sliding surface (3) rather than the third portion (Pc) in a front view (for example, FIG. 8) visually recognized along the center line. Including the fourth part (Pd) located on the end side of
The rigidity of the fourth portion (Pd) is equal to the rigidity of the third portion (Pc).

According to the configuration of the above (13), in the above front view (for example, FIG. 8), the rigidity of the flexible support portion (4) is centered on the end side portion (Pd) and this portion (Pd). It is equal to the part (Pc) located on the side. As described above, the one-sided contact of the shaft (S) with respect to the bearing metal (1) becomes smaller from the portion where the one-sided contact of the shaft (S) is the largest toward both sides of the bearing metal (1) in the circumferential direction. Therefore, for example, in the front view (for example, FIG. 8), the center (front center position) of the flexible support portion (4) extending along the circumferential direction of the bearing metal (1) is set to the axis (S) with respect to the bearing metal (1). If the flexible support portion (4) is configured so as to satisfy the above-mentioned rigidity relationship while adjusting to the portion having the largest one-sided contact of), the thickness of the flexible support portion (4) (the above-mentioned height width (H)). ) Is made larger at the portion (Pc) located on the center side than at the end side portion (Pd), so that the portion where the shaft (S) with the bearing metal (1) has a larger one-sided contact with the bearing metal (1) becomes larger. The bearing metal (1) can be easily bent according to the one-sided contact of the shaft (S).

(14) In some embodiments, in the configurations (1) to (13) above,
The flexible support portion (4) has a hollow portion.
According to the configuration of the above (14), the rigidity of the flexible support portion (4) can be changed to a desired size by changing the density of the cavity portion in the flexible support portion (4).

(15) In some embodiments, in the configuration of (14) above,
The flexible support portion (4) has a porous structure.
According to the configuration of (15) above, the flexible support portion (4) has a porous structure (porous structure) such as a lattice structure. The flexible support portion (4) can be appropriately provided by the lattice structure formed by using a three-dimensional modeling device such as a 3D printer.

(16) In some embodiments, in the configurations (1) to (15) above,
The flexible support portion (4) is elastically deformed in the direction of the load received by bending the shaft (S).
According to the configuration of (16) above, the flexible support portion (4) is elastically deformed in the direction of one-sided contact received from the bent shaft (S). As a result, the end side of the bearing metal (1) can be bent, so that it is possible to prevent the shaft (S) from hitting the end of the bearing metal (1).

1 Bearing metal 1c Crank pin bearing 1m Main bearing 1p Piston pin bearing 2 Main body 3 Sliding surface 4 Flexible support 5 Connecting rod 5b Bolt 6 Large end 6t Crank pin hole (through hole)
7 Small end 71 Piston pin (shaft)
7t piston pin hole (through hole)
9 Crankshaft 91 Crank pin (shaft)
92 Crank journal (axis)
94 Aperture T Through hole Et Main shaft hole (through hole)
S-axis CL bearing metal, center line of through hole Ds rod axial direction Dr center line direction (extending direction of center line)
C Bearing metal center Cb Front center position (center in front view of flexible support)
R Height and width of the soft support part attached to the end of the soft support part W Depth width of the soft support part Wa Distance from the end to the center of the bearing metal Pa First part of the soft support part Pb Soft support part 2nd part Pc 3rd part of flexible support Pd 4th part of flexible support

Claims

A bearing metal for swingably supporting the connecting rod with respect to a shaft which is a piston pin installed in a through hole formed at a small end of the connecting rod.
The main body installed on the inner peripheral surface of the through hole and
A sliding surface formed on the inner peripheral side of the main body portion and configured to be slidable with respect to the shaft is provided.
An engine in which at least a part of the inside of the main body has a flexible support portion that elastically deformably supports both end sides of the sliding surface by having a rigidity lower than that of the surrounding portion. For bearing metal.
The engine bearing metal according to claim 1, wherein the flexible support portion is provided in the direction toward the large end portion in the axial direction of the connecting rod with respect to the center line passing through the cross-sectional center of the through hole.
A bearing metal for rotatably supporting a shaft, which is a crank pin of a crankshaft installed in a through hole formed at the large end of a connecting rod.
The main body installed on the inner peripheral surface of the through hole and
A sliding surface formed on the inner peripheral side of the main body portion and configured to be slidable with respect to the shaft is provided.
An engine in which at least a part of the inside of the main body has a flexible support portion that elastically deformably supports both end sides of the sliding surface by having a rigidity lower than that of the surrounding portion. For bearing metal.
The third aspect of the present invention, wherein the flexible support portion is provided in both the large end side direction and the small end side direction in the axial direction of the connecting rod with respect to the center line passing through the cross-sectional center of the through hole. Bearing metal for engines.
It is a bearing metal for rotatably supporting the shaft, which is the crank journal of the crankshaft installed in the through hole formed in the engine body.
The main body installed on the inner peripheral surface of the through hole and
A sliding surface formed on the inner peripheral side of the main body portion and configured to be slidable with respect to the shaft is provided.
A flexible support portion is formed in at least a part of the inside of the main body portion to elastically and deformably support at least one end side of the sliding surface by having a rigidity lower than that of the surrounding portion. Bearing metal for engines.
The engine bearing metal according to claim 5, wherein the flexible support portion is provided below the center line passing through the center of the cross section of the through hole.
The engine bearing metal according to any one of claims 1 to 6, wherein the flexible support portion is formed on the end side of the main body portion with respect to the center.
The flexible support includes a first portion aligned with each other along a center line passing through the center of the cross section of the bearing metal, and a second portion located closer to the end of the sliding surface than the first portion.
The engine bearing metal according to claim 7, wherein the rigidity of the second portion is lower than the rigidity of the first portion.
The flexible support includes a first portion aligned with each other along a center line passing through the center of the cross section of the bearing metal, and a second portion located closer to the end of the sliding surface than the first portion.
The engine bearing metal according to claim 7, wherein the rigidity of the second portion is equal to the rigidity of the first portion.
The engine bearing metal according to claim 8 or 9, wherein the amount of deformation of the bearing metal when the engine is driven increases toward the end side of the sliding surface along the center line.
Any one of claims 1 to 10 provided so that the flexible support portion extends along the sliding surface in a front view viewed along a center line passing through the center of the cross section of the through hole. Bearing metal for engines as described in the section.
The flexible support portion includes a third portion and a fourth portion located on the end side of the third portion in a front view in which the bearing metal is visually recognized along the extending direction of the center line.
The engine bearing metal according to claim 11, wherein the rigidity of the fourth portion is higher than the rigidity of the third portion.
The flexible support portion includes a third portion and a fourth portion located closer to the end portion of the sliding surface than the third portion in a front view viewed along the center line.
The engine bearing metal according to claim 11, wherein the rigidity of the fourth portion is equal to the rigidity of the third portion.
The engine bearing metal according to any one of claims 1 to 13, wherein the flexible support portion has a hollow portion.
The engine bearing metal according to claim 14, wherein the flexible support portion has a porous structure.
The engine bearing metal according to any one of claims 1 to 15, wherein the flexible support portion is elastically deformed in the direction of a load received by bending the shaft.