JP2017106490A - Bearing structure of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bearing structure of an internal combustion engine capable of easily supplying a lubricant to a sliding face of a washer.SOLUTION: A bearing structure of an internal combustion engine includes: a bearing portion 10 and a bearing cap 20 having a bearing hole 11 and a bearing hole 21 for radially supporting a crank shaft 2; and a washer 40 disposed on the bearing portion 10 and having a sliding face 41 receiving axial force of the crank shaft 2. The bearing portion 10 has a strike 12 formed by axially recessing a peripheral edge portion of the bearing hole 11 and accommodating the washer 40. The bearing cap 20 has a guide portion 22 formed by axially recessing a peripheral edge portion of the bearing hole 21 and adjacent to upstream-side and downstream-side end portions in a rotating direction of the crank shaft 2, of the strike 12.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a bearing structure for an internal combustion engine.

  Conventionally, the technology of a bearing structure for an internal combustion engine has been publicly known. For example, as described in Patent Document 1.

  Patent Document 1 discloses a plain bearing including a cylinder block, a bearing cap provided at a lower portion of the cylinder block, and a half member disposed on an inner peripheral surface of the cylinder block and the bearing cap. Yes. In the slide bearing described in Patent Document 1, a washer mounting groove is formed in the cylinder block, and a thrust washer is disposed in the washer mounting groove.

  However, the sliding bearing described in Patent Document 1 has room for improvement in terms of easy supply of lubricating oil to the sliding surface of the washer.

Japanese Patent Laying-Open No. 2015-169293

  The present invention has been made in view of the above situation, and a problem to be solved is to provide a bearing structure for an internal combustion engine that can easily supply lubricating oil to a sliding surface of a washer. is there.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

  That is, in claim 1, a support member having a support portion that supports the crankshaft from the radial direction, a washer disposed on the support member and having a sliding surface that receives an axial force of the crankshaft, The support member is formed by denting a peripheral edge portion of the support portion in the axial direction, and a first concave portion for accommodating the washer, and a peripheral edge portion of the support portion is recessed in the axial direction. And a second recess that is adjacent to at least one of the upstream end and the downstream end of the first recess in the rotational direction of the crankshaft.

  In Claim 2, the said supporting member is arrange | positioned so that the 1st member which has the 1st supporting part which supports the said crankshaft from radial direction one side, and a said 1st member may be used, The said crankshaft A second member having a second support portion that is supported from the other side in the radial direction, and the first recess is formed by denting a peripheral edge portion of the first support portion of the first member in the axial direction. And is formed such that at least an end of the crankshaft on the downstream side in the rotational direction is opened to the surface of the first member facing the second member, and the second recess is The second member is formed by denting the peripheral edge portion of the second support portion in the axial direction, and the end portion on the upstream side in the rotation direction of the crankshaft is the first member of the second member. Upstream formed to be open to the opposite surface side of Those having an opening.

  According to a third aspect of the present invention, the second recess has a downstream opening formed such that an end of the crankshaft on the downstream side in the rotation direction is opened to the surface of the second member facing the first member. It further has a part.

  In Claim 4, said 2nd recessed part is said upstream open part and said downstream open | release by denting the peripheral part of said 2nd support part of said 2nd member over the perimeter in the said axial direction. It is formed so that a part may connect.

  According to a fifth aspect of the present invention, the second recess is formed so that the radial width becomes wider toward the downstream side in the rotation direction of the crankshaft.

  According to a sixth aspect of the present invention, the upstream open portion of the second recess is formed so that the depth is equal to or greater than the depth of the first recess.

  In Claim 7, The said supporting member is arrange | positioned so that the said 1st member may be opposed to the 1st member which has a 1st support part which supports the said crankshaft from the radial direction one side, The said crankshaft A second member having a second support portion that is supported from the other side in the radial direction, and the first recess is formed by denting a peripheral edge portion of the first support portion of the first member in the axial direction. The second recess is formed by denting the peripheral edge of the first support portion of the first member in the axial direction, and the rotation direction of the crankshaft of the first recess It is formed so as to be adjacent to the upstream end.

  As effects of the present invention, the following effects can be obtained.

  According to the first aspect, the lubricating oil can be easily supplied to the sliding surface of the washer.

  According to the second aspect, it is possible to easily supply the lubricating oil to the sliding surface of the washer.

  According to the third aspect, the lubricating oil can be easily guided to the sliding surface on the upstream side in the rotation direction of the crankshaft of the washer.

  According to the fourth aspect of the present invention, it is possible to easily guide the lubricating oil supplied to the upstream opening portion to the downstream opening portion.

  According to the fifth aspect of the present invention, the lubricating oil supplied to the upstream opening portion can be easily guided to the sliding surface on the upstream side in the rotation direction of the crankshaft of the washer.

  In Claim 6, it can prevent that lubricating oil collides in the opposing surface of a 1st member and a 2nd member.

  According to the seventh aspect, the lubricating oil can be easily guided to the sliding surface on the upstream side in the rotation direction of the crankshaft of the washer.

1 is an exploded perspective view of a part of a bearing device having a bearing structure according to an embodiment of the present invention. Similarly, a cross-sectional view. (A) The front view of a bearing part. (B) Similarly, a bottom view. (A) Front view of bearing cap. (B) Similarly, a plan view. The front view of a washer. AA sectional drawing of FIG. (A) The front view of the bearing cap which concerns on another example of Fig.4 (a). (B) Similarly, a plan view. (A) The front view of the bearing cap which concerns on another example of Fig.4 (a). (B) Similarly, a plan view. (A) The front view of the bearing cap which concerns on another example of Fig.4 (a). (B) Similarly BB expanded sectional view. (B) Similarly, CC sectional drawing. (A) AA sectional drawing of FIG. 2 which concerns on 2nd embodiment. (B) Its DD sectional drawing.

  In the following, the directions indicated by arrow U, arrow D, arrow F, arrow B, arrow L and arrow R in the figure are defined as upward, downward, forward, backward, leftward and rightward, respectively. To explain.

  First, the outline | summary of a structure of the bearing apparatus 1 which concerns on one Embodiment of this invention is demonstrated using FIGS.

  A bearing device 1 according to an embodiment of the present invention is provided in an engine (internal combustion engine). The bearing device 1 mainly includes a crankshaft 2 and a bearing structure 3.

  The crankshaft 2 is connected to a connecting rod (not shown) of the engine so as to rotate clockwise in a front view. The crankshaft 2 mainly includes a crank journal 2a, a crank arm 2b, and a thrust collar 2c.

  The crank journal 2 a is a part that constitutes the rotating shaft of the crankshaft 2. The crank journal 2a is formed in a cylindrical shape. The crank journal 2a is arranged with the axial direction directed in the front-rear direction.

  The crank arm 2b is a part that connects the crank journal 2a and a crank pin (not shown). The crank arm 2b is formed in a plate shape extending in the vertical direction. The crank arm 2b is disposed at the front end and the rear end of the crank journal 2a, respectively, with the plate surface directed in the front-rear direction. In FIG. 1, the illustration of the front crank arm 2b is omitted.

  The thrust collar 2c is a portion formed in an annular plate shape. The thrust collar 2c is formed integrally with the crank journal 2a on the outer peripheral surface side of the crank journal 2a. The thrust collar 2c is disposed at the front end and the rear end of the crank journal 2a, respectively.

  The bearing structure 3 supports the crankshaft 2. The bearing structure 3 includes a bearing portion 10, a bearing cap 20, a main bearing 30 and a washer 40.

  The bearing portion 10 shown in FIGS. 1 to 3 is a portion that is formed in a lower portion of a cylinder block (not shown) and supports a crankshaft 2 described later from above. A bearing hole 11, a seat 12 and an internal oil passage 13 are formed in the bearing portion 10.

  The bearing hole 11 supports the crankshaft 2 from above. The bearing hole 11 is a part that accommodates a main bearing 30 described later. The bearing hole 11 is formed so as to penetrate the bearing portion 10 in the front-rear direction. The bearing hole 11 is formed in a semicircular shape with the lower part opened in a front view.

  The seat 12 is a concave portion formed on the radially outer side of the bearing hole 11. The seats 12 are respectively formed on the front side and the rear side of the bearing portion 10. The front seat 12 is formed so as to be recessed backward from the front surface of the bearing portion 10. The rear seat 12 is formed so as to be recessed forward from the rear surface of the bearing portion 10. The seat 12 is formed in a semi-annular shape adjacent to the peripheral edge of the bearing hole 11 in a front view (back view). The seat 12 is formed such that its axis coincides with the axis of the bearing hole 11. The receiving seat 12 is formed so that both end portions thereof are opened to the lower surface of the bearing portion 10 (a surface facing a bearing cap 20 described later).

  The internal oil passage 13 shown in FIG. 2 is for supplying lubricating oil from the engine oil pump (not shown) to the crankshaft 2 side. The internal oil passage 13 is formed so as to extend in the vertical direction inside the bearing portion 10. The lower end of the internal oil passage 13 is opened in the bearing hole 11.

  The bearing cap 20 shown in FIGS. 1, 2, and 4 is a portion disposed below the bearing portion 10. The bearing cap 20 is formed in a block shape. The bearing cap 20 is disposed so as to face the bearing portion 10. Specifically, the bearing cap 20 is disposed such that the upper surface thereof faces and abuts against the bottom surface of the bearing portion 10. Details of the configuration of the bearing cap 20 will be described later.

  The main bearing 30 shown in FIG.1 and FIG.2 supports the crankshaft 2 rotatably. The main bearing 30 is formed in a semi-cylindrical shape. The main bearings 30 are respectively disposed above and below the crank journal 2a of the crankshaft 2. The upper main bearing 30 is disposed in the bearing hole 11 with the open side facing downward. The lower main bearing 30 is disposed in a bearing hole 21 described later with the open side facing upward. Thereby, the upper main bearing 30 and the lower main bearing 30 are disposed so as to support the crank journal 2a from above and below, respectively. A lubricating oil passage 31 and a through hole 32 are formed in the upper main bearing 30. A chamfered portion 33 is formed on the upper main bearing 30 and the lower main bearing 30.

  The lubricating oil passage 31 is a groove formed on the inner peripheral surface of the upper main bearing 30. Lubricating oil passage 31 is formed to extend along the circumferential direction of upper main bearing 30.

  The through hole 32 is a hole penetrating from the lubricating oil passage 31 to the outer peripheral surface of the upper main bearing 30. The through hole 32 is formed at a substantially central portion in plan view of the upper main bearing 30. The through hole 32 extends in the vertical direction and communicates with the internal oil passage 13 formed in the bearing portion 10.

  The chamfered portion 33 is a portion cut out inside the contact surfaces of the upper main bearing 30 and the lower main bearing 30 (see FIG. 6). The chamfered portion 33 is formed as an inclined surface that connects the contact surface and the inner peripheral surface of the main bearing 30. Thus, the chamfered portion 33 forms a space having a substantially isosceles triangle shape with the apex facing outward in a front view between the crank journal 2a and the upper main bearing 30 and the lower main bearing 30. The space is formed on both the left and right sides of the crank journal 2a. Inside the space, the lubricating oil can flow along the axial direction of the crankshaft 2.

  The washer 40 shown in FIGS. 1, 2, and 5 receives a force in the axial direction of the crankshaft 2. The washer 40 is formed in a semi-annular plate shape. The washer 40 is fitted to the front receiving seat 12 and the rear receiving seat 12 so that the plate surface on one side faces the thrust collar 2 c of the crankshaft 2. The washer 40 is disposed with the open side facing downward. The washer 40 is disposed such that its axis coincides with the axis of the crankshaft 2. The washer 40 is formed such that its thickness is greater than the depth of the seat 12. The washer 40 includes a sliding surface 41, a circumferential end surface 42, a thrust relief 43, an upstream oil groove 44, and a downstream oil groove 45. In the following description, the washer 40 disposed on the front side of the bearing portion 10 will be described unless otherwise specified.

  The sliding surface 41 is a front plate surface of the washer 40 and is a surface facing the thrust collar 2c. Since the thickness of the washer 40 is larger than the depth of the receiving seat 12, the sliding surface 41 is positioned in front of the front surface of the bearing portion 10. As a result, the sliding surface 41 is formed so as to slide with the thrust collar 2 c when the crankshaft 2 rotates. The sliding surface 41 is formed so as to receive a force in the axial direction of the crankshaft 2.

  The circumferential end surface 42 is an end surface in the circumferential direction of the washer 40. The circumferential end surface 42 is formed at each of circumferential end portions on both the left and right sides of the washer 40. The circumferential end face 42 is formed to be parallel to the horizontal direction.

  The thrust relief 43 is a chamfered portion formed in a portion adjacent to the circumferential end surface 42 in a front view. The thrust relief 43 is formed on the sliding surface 41 side. The thrust relief 43 is formed so as to become thinner toward the circumferential end face 42 side in the circumferential direction of the washer 40.

  The upstream oil groove 44 guides the lubricating oil as appropriate. The upstream oil groove 44 is formed when the sliding surface 41 is recessed. The upstream oil groove 44 is formed so that one end (lower end) thereof is opened to the inner peripheral surface side of the washer 40. The upstream oil groove 44 is formed such that the other end (upper end) is open to the outer peripheral surface side of the washer 40. The upstream oil groove 44 is formed to extend in the vertical direction from the inner peripheral surface of the washer 40 to the outer peripheral surface. The upstream oil groove 44 is formed in a region of the sliding surface 41 on the upstream side in the rotation direction of the crankshaft 2 (hereinafter simply referred to as the upstream side) (region on the left side of the center of the washer 40 in front view).

  The downstream oil groove 45 guides lubricating oil as appropriate. The downstream oil groove 45 is formed when the sliding surface 41 is recessed. The downstream oil groove 45 is formed so that one end (lower end) thereof is opened to the inner peripheral surface side of the washer 40. The downstream oil groove 45 is formed such that the other end (upper end) is opened to the outer peripheral surface side of the washer 40. The downstream oil groove 45 is formed so as to extend in the vertical direction from the inner peripheral surface of the washer 40 to the outer peripheral surface. The downstream oil groove 45 is formed in a region of the sliding surface 41 on the downstream side in the rotation direction of the crankshaft 2 (hereinafter simply referred to as the downstream side) (region on the right side of the center of the washer 40 in front view).

  Next, the structure of the bearing cap 20 which concerns on one Embodiment of this invention is demonstrated using FIG.1 and FIG.4.

  The bearing cap 20 is a portion disposed below the bearing portion 10 as described above. A bearing hole 21 and a guide portion 22 are formed in the bearing cap 20.

  The bearing hole 21 supports the crankshaft 2 from below. The bearing hole 21 is a part that accommodates the main bearing 30. The bearing hole 21 is formed so as to penetrate the upper part of the bearing cap 20 in the front-rear direction. The bearing hole 21 is formed in a semicircular shape with the upper part opened in a front view.

  The guide part 22 guides lubricating oil as appropriate. The guide portions 22 are respectively formed on the front side and the rear side of the bearing cap 20. The front guide portion 22 is formed so as to be recessed rearward from the front surface of the bearing cap 20. The rear guide portion 22 is formed so as to be recessed forward from the rear surface of the bearing cap 20. The guide portion 22 is formed in a substantially semi-annular shape adjacent to the peripheral portion of the bearing hole 21 in front view (rear view) by denting the peripheral portion of the bearing cap 20 over the entire periphery. The guide portion 22 is formed so that the radial width W (distance between the circumferential surface of the bearing hole 21 and the circumferential surface of the guide portion 22 in a front view) increases toward the downstream side. The guide part 22 is formed so that the depth (distance in the axial direction) D2 is constant throughout. The depth D2 of the guide portion 22 is formed to be the same as the depth D1 of the seat 12 (see FIG. 3). The guide portion 22 includes an upstream open portion 22a and a downstream open portion 22b at both ends thereof, so that the both end portions are open to the upper surface of the bearing cap 20 (a surface facing the bearing portion 10 described later). Formed.

  The upstream opening portion 22 a is an upstream (right side) end portion of the guide portion 22. The upstream opening portion 22a is formed so as to open to the upper surface (the surface facing the bearing portion 10) of the bearing cap 20. As a result, the upstream opening 22a is formed adjacent to the downstream end of the seat 12. As described above, since the depth D2 of the guide portion 22 and the depth D1 of the receiving seat 12 are the same, the depth (D2) of the upstream opening portion 22a is the downstream end portion (upstream side) of the receiving seat 12. It is formed to be the same as the depth (D1) of the portion facing the opening 22a. The upstream open portion 22a has a right end overlapped with the circumferential end surface 42 on the downstream side (right side) of the washer 40 in the left-right direction (the same position as the left end of the circumferential end surface 42, or the circumferential direction). (It is located to the right of the left end of the end face 42) (see FIG. 6).

  The downstream open portion 22 b is an end portion on the downstream side (left side) of the guide portion 22. The downstream open portion 22b is formed so as to open to the upper surface of the bearing cap 20 (the surface facing the bearing portion 10). Thereby, the downstream open part 22b is formed to be adjacent to the upstream end of the seat 12. The downstream open portion 22 b is formed to face the left circumferential end surface 42 and the thrust relief 43 of the washer 40. The downstream opening portion 22b is formed so that the width in the left-right direction (that is, the radial width W) is larger than that of the upstream opening portion 22a. The downstream open portion 22b has a left end overlapped with the circumferential end surface 42 on the upstream side (left side) of the washer 40 in the left-right direction (positioned to the left of the right end of the circumferential end surface 42). (See FIG. 6).

  In the bearing device 1 configured as described above, an inner peripheral gap G is formed in a region surrounded by the front end portion of the main bearing 30, the inner peripheral surface of the washer 40, the crank journal 2a, and the front thrust collar 2c. Is formed (see FIGS. 2 and 5). An inner circumferential gap G is also formed in a region surrounded by the rear end portion of the main bearing 30, the inner circumferential surface of the washer 40, the crank journal 2a, and the rear thrust collar 2c.

  Next, the flow path through which the lubricating oil flows will be described with reference to FIGS. 2 and 6. In the following description, the flow path of the lubricating oil in the washer 40 disposed on the front side of the bearing portion 10 will be described unless otherwise specified.

  Lubricating oil discharged from an oil pump (not shown) of the engine flows through the internal oil passage 13 of the bearing portion 10. Next, the lubricating oil flows through the through hole 32 of the main bearing 30 and is supplied to the lubricating oil passage 31. A part of the lubricating oil supplied to the lubricating oil passage 31 flows along the lubricating oil passage 31 (along the circumferential direction of the main bearing 30), and the inner peripheral surface of the main bearing 30 (the inner peripheral surface). And between the outer peripheral surface of the crank journal 2a). In addition, another part of the lubricating oil supplied to the lubricating oil passage 31 is supplied to a crank pin (not shown) through an internal oil passage of the crankshaft 2 (not shown). In addition, another part of the lubricating oil supplied to the lubricating oil passage 31 passes through the gap between the contact surfaces of the upper and lower main bearings 30 (particularly, the space formed by the chamfered portion 33) in the front-rear direction. Flows out into the inner circumferential gap G.

  The lubricating oil that has flowed into the inner circumferential gap G from the space formed by the left chamfered portion 33 passes through the inner circumferential gap G in the rotation direction of the crankshaft 2 (clockwise direction in front view) as the crankshaft 2 rotates. Circulate along. Part of the lubricating oil flowing through the inner circumferential gap G enters the upstream oil groove 44 and is supplied to the sliding surface 41 adjacent to the downstream side of the upstream oil groove 44 via the upstream oil groove 44. Is done. The lubricating oil circulates on the sliding surface 41 along the rotation direction of the crankshaft 2. A part of the lubricating oil that has entered the upstream oil groove 44 flows to the radially outer side of the washer 40 along the upstream oil groove 44, and then the outer peripheral surface of the washer 40 as the crankshaft 2 rotates. Circulate along.

  The lubricating oil flowing through the sliding surface 41 adjacent to the downstream side of the upstream oil groove 44 flows along the rotation direction of the crankshaft 2, and most of the lubricating oil passes through the downstream oil groove 45 and remains as it is. It is supplied to the sliding surface 41 adjacent to the downstream side of the downstream oil groove 45. Further, the lubricating oil flowing along the outer peripheral surface of the washer 40 enters the downstream oil groove 45, and the sliding surface 41 adjacent to the downstream side of the downstream oil groove 45 via the downstream oil groove 45. To be supplied. The lubricating oil flows along the rotation direction of the crankshaft 2 and enters the bearing cap 20 side.

  Also, the lubricating oil that does not enter the upstream oil groove 44 and flows through the inner circumferential gap G flows through the inner circumferential gap G along the rotation direction of the crankshaft 2, and is on the right side of the bearing portion 10 and the bearing cap 20. Reach the seam (contact surface).

  Of the lubricating oil that has circulated through the inner circumferential gap G and reached the right joint, the lubricating oil that has circulated on the inner circumferential side close to the crankshaft 2 (the front surface of the upper main bearing 30) The bearing cap 20 is entered by flowing through the front surface of the lower main bearing 30 as it is.

  On the other hand, of the lubricating oil that has circulated through the inner peripheral gap G and reached the right joint portion, the outer peripheral side close to the washer 40 (the outer peripheral surface of the upper main bearing 30 in the seat 12 and the inner periphery of the washer 40). The lubricating oil that has circulated through the portion between the surface and the surface enters the bearing cap 20 side through the guide portion 22 through the upstream opening portion 22a. Thus, since the guide portion 22 is formed, the upper surface of the bearing cap 20 (the surface facing the bearing portion 10) does not protrude into the flow path of the lubricating oil. It can distribute | circulate downstream, without colliding with (contact surface).

  The lubricating oil that has entered the bearing cap 20 side is dragged by the rotation of the crankshaft 2 and flows below the crankshaft 2. Similarly, the lubricating oil that has flowed out of the space formed by the right chamfered portion 33 into the inner circumferential gap G is also dragged by the rotation of the crankshaft 2 and flows below the crankshaft 2. A part of the lubricating oil flowing under the crankshaft 2 flows through the front surface of the lower main bearing 30 as it is and reaches the left joint portion of the bearing portion 10 and the bearing cap 20. Further, the other part of the lubricating oil flowing under the crankshaft 2 flows through the guide portion 22 and reaches the downstream opening portion 22b. A part of the lubricating oil flowing through the front surface of the lower main bearing 30 also enters the guide portion 22 by being shaken radially outward by centrifugal force or gravity, and then reaches the downstream open portion 22b.

  The lubricating oil that has reached the downstream opening 22 b is supplied to the sliding surface 41 via the thrust relief 43 on the upstream side (left side) of the washer 40.

  Thus, in this embodiment, since the guide part 22 adjacent to the upstream edge part and downstream edge part of the seat 12 is formed, lubricating oil is smoothly supplied to the sliding surface 41 of the washer 40. It can be distributed. Further, since the upper surface of the bearing cap 20 (the surface facing the bearing portion 10) does not protrude into the flow path of the lubricating oil, the lubricating oil is absorbed by the bearing cap at the joint (on the right side) of the bearing portion 10 and the bearing cap 20. Colliding with the upper surface of 20 can be prevented. Therefore, since the flow of the lubricating oil can be prevented from being disturbed by the collision, the amount of the lubricating oil discharged to the outside of the sliding surface 41 of the washer 40 can be reduced.

  Further, since the downstream open portion 22b is formed so as to face the left circumferential end face 42 and the thrust relief 43 of the washer 40, the crankshaft 2 is located below the lower main bearing (through the thrust relief 43). 30) can be guided to the sliding surface 41 of the washer 40. Accordingly, the lubricating oil can be easily supplied to the sliding surface 41 of the washer 40. Further, since the upstream opening portion 22a and the downstream opening portion 22b are connected to each other in the guide portion 22, the lubricating oil that has entered the upstream opening portion 22a flows along the guide portion 22 to the downstream opening portion 22b. Can be guided to.

  Further, since the guide portion 22 is formed so that the radial width W becomes wider toward the downstream side, the lubricating oil that has circulated downstream along the guide portion 22 is guided to the radially outer side. As a result, it can be easily guided to the washer 40 side.

  Further, since the depth D2 of the upstream opening 22a is formed to be the same as the depth D1 of the downstream end of the seat 12, the lubricating oil is upstream from the downstream end of the seat 12. When entering the side opening portion 22a, it is possible to prevent the upper surface of the bearing cap 20 from colliding.

  Therefore, the lubricating oil can be easily supplied to the sliding surface 41 of the washer 40, and the amount of the lubricating oil supplied to the sliding surface 41 can be increased. Therefore, since an oil film is easily formed on the sliding surface 41, the friction coefficient can be lowered, and the washer 40 can be prevented from being seized and an increased amount of wear.

As described above, the bearing structure 3 according to the present embodiment includes the bearing portion 10 and the bearing cap 20 (support member) having the bearing hole 11 and the bearing hole 21 (support portion) that support the crankshaft 2 from the radial direction, A washer 40 disposed on the bearing portion 10 and having a sliding surface 41 for receiving an axial force of the crankshaft 2, and the bearing portion 10 has a peripheral edge portion of the bearing hole 11 in the axial direction. The bearing cap 20 is formed by denting the peripheral edge of the bearing hole 21 in the axial direction. The bearing cap 20 has a seat 12 (first recess) for receiving the washer 40. Thus, the bearing 12 has guide portions 22 (second recesses) adjacent to the upstream and downstream ends of the crankshaft 2 in the rotational direction.
With this configuration, it is possible to easily supply the lubricating oil to the sliding surface 41 of the washer 40.

The support member faces the bearing portion 10 and a bearing portion 10 (first member) having a bearing hole 11 (first support portion) that supports the crankshaft 2 from above (one side in the radial direction). And a bearing cap 20 (second member) having a bearing hole 21 (second support portion) that supports the crankshaft 2 from below (the other side in the radial direction). Is formed by denting the peripheral edge portion of the bearing hole 11 of the bearing portion 10 in the axial direction, and at least the end portion on the downstream side in the rotation direction of the crankshaft 2 is the bearing of the bearing portion 10. The guide portion 22 is formed so as to be opened to the surface facing the cap 20, and the peripheral portion of the bearing hole 21 of the bearing cap 20 is recessed in the axial direction. The crank End of the second rotating direction upstream side are those having the formed upstream opening 22a so that the is opened to a surface facing the bearing portion 10 of the bearing cap 20.
With this configuration, it is possible to easily supply the lubricating oil to the sliding surface 41 of the washer 40.

Further, the guide portion 22 includes a downstream opening portion 22b formed so that an end portion on the downstream side in the rotation direction of the crankshaft 2 is opened to a surface facing the bearing portion 10 of the bearing cap 20. In addition.
With this configuration, it is possible to easily guide the lubricating oil to the sliding surface 41 on the upstream side in the rotation direction of the crankshaft 2 of the washer 40.

In addition, the guide portion 22 is configured such that the upstream open portion 22a and the downstream open portion 22b are formed by denting the peripheral portion of the bearing hole 21 of the bearing cap 20 over the entire circumference in the axial direction. It is formed to be connected.
With this configuration, it is possible to easily guide the lubricating oil supplied to the upstream opening 22a to the downstream opening 22b.

The guide portion 22 is formed such that the radial width W increases toward the downstream side in the rotational direction of the crankshaft 2.
By being configured in this way, the lubricating oil supplied to the upstream opening 22a can be easily guided to the sliding surface 41 on the upstream side in the rotation direction of the crankshaft 2 of the washer 40.

The upstream open portion 22a of the guide portion 22 is formed such that the depth D2 is the same as the depth D1 of the seat 12.
By being configured in this manner, it is possible to prevent the lubricating oil from colliding with the facing surface between the bearing portion 10 and the bearing cap 20.

In addition, the bearing part 10 and the bearing cap 20 which concern on this embodiment are one form of the support member which concerns on this invention.
Moreover, the bearing part 10 which concerns on this embodiment is one form of the 1st member which concerns on this invention.
Moreover, the bearing cap 20 which concerns on this embodiment is one form of the 2nd member which concerns on this invention.
Moreover, the bearing hole 11 and the bearing hole 21 which concern on this embodiment are one form of the support part which concerns on this invention.
Moreover, the bearing hole 11 which concerns on this embodiment is one form of the 1st support part which concerns on this invention.
Moreover, the bearing hole 21 which concerns on this embodiment is one form of the 2nd support part which concerns on this invention.
Moreover, the seat 12 which concerns on this embodiment is one form of the 1st recessed part which concerns on this invention.
Moreover, the guide part 22 which concerns on this embodiment is one form of the 2nd recessed part which concerns on this invention.

  As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said structure, A various change is possible within the range of the invention described in the claim.

  For example, in the present embodiment, the bearing portion 10 and the bearing cap 20 are separate members, but may be integrally formed. Accordingly, the bearing hole 11 and the bearing hole 21 may be formed integrally as well. In this case, the guide part 22 should just be formed so that it may adjoin at least one of the upstream edge part of the seat 12, and a downstream edge part.

  Further, in the present embodiment, the seat 12 is formed on the bearing portion 10 and the washer 40 is disposed on the seat 12, but the present invention is not limited to this, and the bearing cap 20 The receiving seat 12 may be formed, and the washer 40 may be disposed on the receiving seat 12. Further, the seat 12 may be formed across the bearing portion 10 and the bearing cap 20, and the washer 40 is disposed across the bearing portion 10 and the bearing cap 20 along with this. Also good.

  In the present embodiment, the seat 12 is formed over the entire circumference of the peripheral edge of the bearing hole 11, but the present invention is not limited to this, and the bearing hole 11 or the bearing Part of the peripheral edge of the hole 21, part of the peripheral part of the bearing hole 11 and part of the peripheral part of the bearing hole 21, or part of the peripheral part of the peripheral part of the bearing hole 21 and part of the peripheral part of the bearing hole 11. It may be formed.

  Further, in the present embodiment, the washer 40 is formed in a semi-annular shape, but the shape of the washer 40 is not limited to this, and for example, is formed in a partial annular shape other than the semi-annular shape. May be.

  In the present embodiment, the guide portion 22 is formed on the bearing cap 20. However, the present invention is not limited to this, and the guide portion 22 is formed on the bearing portion 10. May be. Further, the guide portion 22 may be formed across the bearing portion 10 and the bearing cap 20.

  Further, in the present embodiment, the seat 12 is formed on the bearing portion 10 (the washer 40 is disposed) and the guide portion 22 is formed on the bearing cap 20, but the present invention is limited to this. Instead, the bearing portion 10 may be formed with the seat 12 and the guide portion 22, and the bearing cap 20 may be formed with the seat 12 and the guide portion 22.

  In the present embodiment, the guide portion 22 is formed so that the radial width W becomes wider toward the downstream side. However, the present invention is not limited to this, and the circumferential direction W In this case, the radial width W may be constant.

  Further, in the present embodiment, the guide portion 22 is formed so that the depth D2 of the upstream opening portion 22a is the same as the depth D1 of the downstream end portion of the receiving seat 12. The invention is not limited to this, and may be formed such that the depth D2 of the upstream opening 22a is larger than the depth D1 of the downstream end of the receiving seat 12.

  In the present embodiment, the guide portion 22 has the downstream opening portion 22b. However, the present invention is not limited to this, and as shown in FIG. 7, only the upstream opening portion 22a is provided. You may have. This can also prevent the flow of the lubricating oil from being disturbed by the collision, so that the amount of the lubricating oil discharged to the outside of the sliding surface 41 of the washer 40 can be reduced. Moreover, although the guide part 22 shall have the upstream opening part 22a, this invention is not limited to this, You may have only the downstream opening part 22b. This also makes it easy to supply the lubricating oil flowing under the crankshaft 2 (the front surface of the lower main bearing 30) to the sliding surface 41 of the washer 40.

  In the present embodiment, the guide portion 22 is formed so that the upstream side open portion 22a and the downstream side open portion 22b are connected (over the entire circumference of the peripheral portion of the bearing hole 21). The present invention is not limited to this, and the upstream opening 22a and the downstream opening 22b may be formed separately as shown in FIG. This also makes it easy to supply the lubricating oil flowing under the crankshaft 2 (the front surface of the lower main bearing 30) to the sliding surface 41 of the washer 40.

  In the present embodiment, the guide portion 22 is formed so that the depth D2 is constant in any portion, but the present invention is not limited to this, and is shown in FIG. In this way, the depth D2 can be reduced toward the downstream side. Thereby, since the depth of the downstream open part 22b becomes small, the level | step difference with the thrust relief 43 of the washer 40 becomes small. Therefore, it is possible to easily supply the lubricating oil from the downstream opening portion 22b to the sliding surface 41.

In the present embodiment, the upstream open portion 22a is formed so that the right end portion thereof overlaps with the circumferential end surface 42 on the downstream side (right side) of the washer 40 in the left-right direction. The present invention is not limited to this, and the right end portion thereof may be located on the right side of the right end portion (outer peripheral surface) of the circumferential end surface 42.
In the present embodiment, the downstream opening 22b is formed so that the left end thereof overlaps with the upstream end (left side) circumferential end surface 42 of the washer 40 in the left-right direction. The present invention is not limited to this, and the left end portion may be located on the left side of the left end portion (outer peripheral surface) of the circumferential end surface 42.

  Next, the bearing structure 4 which concerns on 2nd embodiment of this invention is demonstrated using FIG.

  The bearing structure 4 according to the second embodiment is different from the bearing structure 3 according to the first embodiment in that instead of the bearing portion 10, the bearing cap 20 and the washer 40, a bearing portion 50, a bearing cap 60 and a washer 70 are provided. It is a point to have. Therefore, below, about the structure same as the bearing structure 3 which concerns on 1st embodiment among the bearing structures 4 which concern on 2nd embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  The bearing portion 50 is a portion that is formed in a lower portion of a cylinder block (not shown) and supports the crankshaft 2 from above. A bearing hole 51, a receiving seat 52, an internal oil passage 53, and a guide portion 54 are formed in the bearing portion 50.

  The bearing hole 51 supports the crankshaft 2 from above. The bearing hole 51 is a part that accommodates the main bearing 30. The bearing hole 51 is formed so as to penetrate the bearing portion 50 in the front-rear direction. The bearing hole 51 is formed in a semicircular shape whose bottom is opened in a front view.

  The seat 52 is a concave portion formed on the outer side in the radial direction of the bearing hole 51. The receiving seats 52 are respectively formed on the front side and the rear side of the bearing portion 50 (the rear receiving seats 52 are not shown in FIG. 10). The front seat 52 is formed so as to be recessed rearward from the front surface of the bearing portion 50. The rear seat 52 is formed to be recessed forward from the rear surface of the bearing portion 50. The seat 52 is formed in a ¼ partial annular shape adjacent to the right half of the peripheral edge of the bearing hole 51 in a front view (back view). The seat 52 is formed such that its axis coincides with the axis of the bearing hole 51. The seat 52 is formed such that the downstream end is opened to the lower surface of the bearing portion 50 (a surface facing a bearing cap 60 described later).

  The internal oil passage 53 is for supplying lubricating oil from the engine oil pump (not shown) to the crankshaft 2 side. The internal oil passage 53 is formed so as to extend in the vertical direction inside the bearing portion 50. The lower end of the internal oil passage 53 is opened in the bearing hole 51.

  The guide part 54 guides lubricating oil as appropriate. The guide portions 54 are respectively formed on the front side and the rear side of the bearing portion 50 (the rear guide portion 54 is not shown in FIG. 10). The front guide portion 54 is formed so as to be recessed rearward from the front surface of the bearing portion 50. The rear guide portion 54 is formed so as to be recessed forward from the rear surface of the bearing portion 50. The guide portion 54 is formed in a substantially ¼ partial annular shape adjacent to the peripheral portion of the bearing hole 51 in a front view (rear view) by denting the left half of the peripheral portion of the bearing portion 50. The downstream end (right end) of the guide portion 54 is formed adjacent to the upstream end (left end) of the receiving seat 52. The upstream end portion (lower end portion) of the guide portion 54 is formed so as to be open to the lower surface of the bearing portion 50 (a surface facing a bearing cap 60 described later). The guide portion 54 is formed such that the width in the radial direction (distance between the circumferential surface of the bearing hole 51 and the circumferential surface of the guide portion 54 in a front view) increases toward the downstream side. The depth of the guide portion 54 is formed to be smaller than the depth of the receiving seat 52.

  The bearing cap 60 is a portion disposed below the bearing portion 50. The bearing cap 60 is formed in a block shape. The bearing cap 60 is disposed so as to face the bearing portion 50. Specifically, the bearing cap 60 is disposed such that the upper surface thereof faces and abuts against the bottom surface of the bearing portion 50. A bearing hole 61 is formed in the bearing cap 60.

  The bearing hole 61 supports the crankshaft 2 from below. The bearing hole 61 is a part that accommodates the main bearing 30. The bearing hole 61 is formed so as to penetrate the upper part of the bearing cap 60 in the front-rear direction. The bearing hole 61 is formed in a semicircular shape with the top opened in front view.

  The washer 70 receives a force in the axial direction of the crankshaft 2. The washer 70 is formed in a ¼ partial annular plate shape with a central angle being a right angle. The washer 70 is fitted into the front receiving seat 52 and the rear receiving seat 52 so that the plate surface on one side faces the thrust collar 2c of the crankshaft 2 (the rear washer 70 is shown in FIG. 10). (Not shown). The washer 70 includes a sliding surface 71 and a thrust relief 72. In the following description, the washer 70 disposed on the front side of the bearing portion 50 will be described unless otherwise specified.

  The sliding surface 71 is a front plate surface of the washer 70 and is a surface facing the thrust collar 2c. On the sliding surface 71, a land portion 71a and a tapered portion 71b are formed.

  The land portion 71 a is a flat surface formed on the downstream side in the right end portion (lower end portion) of the sliding surface 71, that is, the sliding surface 71. The thickness of the washer 70 at the portion where the land portion 71 a is formed is formed to be larger than the depth of the seat 52. For this reason, the land portion 71 a is formed so as to be positioned in front of the front surface of the bearing portion 50 and the bearing cap 60. Thereby, the land portion 71a is formed so as to slide with the thrust collar 2c when the crankshaft 2 rotates. The land portion 71 a is formed so as to receive a force in the axial direction of the crankshaft 2.

  The tapered portion 71b is an inclined surface formed adjacent to the upstream side (left side) with respect to the land portion 71a. The taper portion 71b is formed to be inclined so that the thickness becomes thinner toward the upstream side. As with the land portion 71a, the tapered portion 71b is formed so as to slide with the thrust collar 2c during the rotation of the crankshaft 2 and to receive a force in the axial direction of the crankshaft 2.

  The thrust relief 72 is a chamfered portion formed adjacent to the circumferential end surface of the washer 70 in a front view and adjacent to the upstream side (left side) with respect to the tapered portion 71b. The thrust relief 72 is formed on the sliding surface 71 side. The thrust relief 72 is formed so as to become thinner toward the upstream side.

  In the bearing structure 4 configured as described above, the lubricating oil that has flowed out of the space formed by the left chamfered portion 33 can be guided to the thrust relief 72 of the washer 70 through the guide portion 54. Thereby, the lubricating oil can be supplied to the sliding surface 71 (tapered portion 71b and land portion 71a) via the thrust relief 72.

As described above, in the second embodiment, the support member has the bearing portion 50 (first member) having the bearing hole 51 (first support portion) that supports the crankshaft 2 from above (one side in the radial direction). ) And a bearing cap 60 (second member) having a bearing hole 61 (second support portion) that is arranged to face the bearing portion 50 and supports the crankshaft 2 from below (the other side in the radial direction). The seat 52 is formed by denting the peripheral edge portion of the bearing hole 51 of the bearing portion 50 in the axial direction, and the guide portion 54 is formed of the bearing hole of the bearing portion 50. It is formed by denting the peripheral edge of 51 in the axial direction, and is formed so as to be adjacent to the upstream end of the receiving shaft 52 in the rotational direction of the crankshaft 2.
With this configuration, it is possible to easily supply the lubricating oil to the sliding surface 71 of the washer 70.

  The second embodiment of the present invention has been described above, but the present invention is not limited to the above-described configuration, and various modifications can be made within the scope of the invention described in the claims.

  For example, in the second embodiment, the receiving seat 52 and the guide portion 54 are formed on the bearing portion 50, but the receiving seat 52 and the guide portion 54 may be formed on the bearing cap 60. . That is, the bearing cap 60 according to the second embodiment may be the first member according to the present invention, and the bearing portion 50 according to the present embodiment may be the second member according to the present invention.

3, 4 Bearing structure 10, 50 Bearing part 11, 51 Bearing hole 12, 52 Seat 20, 60 Bearing cap 21, 61 Bearing hole 22, 54 Guide part 22a Upstream opening part 22b Downstream opening part 40, 70 Washer 41 71 Sliding surface

Claims (7)

A support member having a support portion for supporting the crankshaft from the radial direction;
A washer disposed on the support member and having a sliding surface for receiving an axial force of the crankshaft;
Comprising
The support member is
A first recess that is formed by denting the peripheral edge of the support portion in the axial direction and accommodates the washer;
A second recess that is formed by denting a peripheral edge of the support portion in the axial direction, and is adjacent to at least one of an upstream end or a downstream end of the first recess in the rotation direction of the crankshaft;
Having
Bearing structure for an internal combustion engine. The support member is
A first member having a first support portion for supporting the crankshaft from one radial side;
A second member that is disposed so as to face the first member and has a second support portion that supports the crankshaft from the other radial side;
Comprising
The first recess is formed by denting a peripheral edge portion of the first support portion of the first member in the axial direction, and at least an end portion on the downstream side in the rotation direction of the crankshaft is the first portion. It is formed so as to be opened on the side facing the second member of the member,
The second recess is formed by denting a peripheral edge portion of the second support portion of the second member in the axial direction, and an end portion on the upstream side in the rotation direction of the crankshaft is the second member. Having an upstream opening formed to be opened on the side facing the first member of
The internal combustion engine bearing structure according to claim 1. The second recess further includes a downstream opening portion formed such that an end portion on the downstream side in the rotation direction of the crankshaft is opened to the surface of the second member facing the first member.
The bearing structure of the internal combustion engine according to claim 2. The second concave portion is formed such that the upstream opening portion and the downstream opening portion are connected by denting the peripheral edge portion of the second support portion of the second member over the entire circumference in the axial direction. Formed,
The bearing structure of the internal combustion engine according to claim 3. The second recess is formed so that the radial width becomes wider toward the downstream side in the rotation direction of the crankshaft.
The bearing structure of the internal combustion engine according to claim 4. The upstream open portion of the second recess is formed such that the depth is equal to or greater than the depth of the first recess.
The bearing structure for an internal combustion engine according to any one of claims 2 to 5. The support member is
A first member having a first support portion for supporting the crankshaft from one radial side;
A second member that is disposed so as to face the first member and has a second support portion that supports the crankshaft from the other radial side;
Comprising
The first recess is formed by denting a peripheral edge portion of the first support portion of the first member in the axial direction,
The second recess is formed by denting a peripheral edge of the first support portion of the first member in the axial direction, and an end of the first recess on the upstream side in the rotation direction of the crankshaft Formed to be adjacent to the
The internal combustion engine bearing structure according to claim 1.

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