JP2021139386A5 - - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing mounting structure for mounting a bearing that supports a rotating shaft of a valve plate provided through an exhaust passage of an automobile, for example , and a manufacturing method thereof .

2. Description of the Related Art Conventionally, as a mounting structure for a bearing that supports a rotating shaft of a valve plate that penetrates an exhaust passage of an automobile, there is a mounting structure for a bearing that supports the rotating shaft of a valve plate in an exhaust valve of Patent Document 1. In this mounting structure, the rotating shaft of the valve body is provided so as to pass through the tubular body forming the exhaust passage, and bearings are installed near both ends so as to support the rotating shaft. Each bearing is housed in a bottomed cylindrical bearing case, and supports a rotating shaft that is inserted through an insertion hole formed in the bottom of the bearing case on the tubular body side. The opposite side of each bearing case to the tubular body is closed with a cap.

Each bearing case is positioned by engaging the engaging portion protruding around the insertion hole of the bottom with the shaft insertion hole of the tubular body, and is fixed to the tubular body by welding the outer periphery of the bottom. By fixing the bearing case, the bearings supporting the vicinity of both ends of the rotating shaft are fixed at fixed positions (see Fig. 3, column 4, lines 3-12 of Patent Document 1).

U.S. Pat. No. 10167785

By the way, when forming the bearing mounting structure of Patent Document 1, normally, a bottomed cylindrical bearing case having an insertion hole in the bottom is formed by cutting, and the bearing is press-fitted into the formed bearing case. A cap is welded to the open top to close. Then, the insertion hole in the bottom portion of the bearing case is positioned so as to correspond to the shaft insertion hole in the tubular body, and the outer periphery of the bottom portion of the bearing case is welded to the tubular body.

However, if the outer circumference of the cylindrical bottom portion of the bearing case, in which the bearing is housed in advance, is welded to the tubular body, the high heat generated by the welding will damage the bearing, leading to damage to the bearing, deterioration of the lubricant in the bearing, and longevity of the bearing. Degradation may occur. Therefore, there is a demand for a structure that can reduce the damage of the welding heat to the bearing.

The present invention has been proposed in view of the above-mentioned problems, and provides a bearing mounting method that can greatly reduce the damage of welding heat to bearings, and reliably prevent damage to bearings, deterioration of lubricants in bearings, and shortening of bearing life. It is an object of the present invention to provide a structure and a method of manufacturing the same .

A bearing mounting structure according to the present invention is a bearing mounting structure for mounting a bearing that supports a rotating shaft that is inserted through a housing, and includes a substantially cylindrical base portion and a base portion extending outward from one end in the axial direction of the base portion. The bearing is housed in a bearing case having a brim formed in the rim, the bearing case is arranged with the brim along the housing, and the bearing case is welded to the housing by the brim. It is characterized by
According to this, by welding the bearing case to the housing at the flange, the distance from the welding point to the bearing is increased, and the amount of heat conducted to the bearing inside the bearing case during welding is reduced as much as possible. , the welding heat damage to the bearing can be greatly reduced. Therefore, it is possible to reliably prevent damage to the bearing, deterioration of the lubricant in the bearing, and shortening of the life of the bearing.

In the bearing mounting structure of the present invention, the housing is a substantially cylindrical tubular body, the flange portion is curved so as to follow the outer peripheral surface of the tubular body, and the bearing case is attached to the tubular body by the flange portion. It is characterized by being welded to the body.
According to this, by forming the collar portion of the bearing case so as to follow the outer peripheral surface of the tubular body, it is possible to attach the bearing case and the bearing housed therein to the outer peripheral surface of the curved tubular body. Also, the damage of welding heat to the bearing can be greatly reduced, and the bearing case can be attached to the outer peripheral surface of the curved tubular body in a stable state with high strength. In addition, when the tubular body is a flow path for exhaust gas, etc., the bearing case can be attached without protruding into the tubular body, in other words, into the flow path and narrowing the cross section of the flow path. can be maintained without decreasing

The bearing mounting structure of the present invention is characterized in that the flange portion is formed so as to be bent from one axial end portion of the base portion.
According to this, the bearing case can be bent and formed by press working or the like, and the bearing case can be obtained without cutting, which is expensive to process, and the product provided with the bearing case and the bearing mounting structure. It is possible to reduce the manufacturing cost of and efficiently manufacture. In particular, when forming a bearing case with a curved flange that follows the outer circumference of the pipe by cutting, the processing cost is considerably high and the processing time is considerably long. can be obtained at low cost and with high manufacturing efficiency.

The bearing mounting structure of the present invention comprises: the first bearing supporting one end side of the rotating shaft in the axial direction; the first bearing case housing the first bearing; The second bearing that supports the end portion side and the second bearing case that accommodates the second bearing case are provided, and one of the first bearing case and the second bearing case is located on one side of the base portion in the axial direction. It is characterized by being an integrally formed member formed with a closed top located on the end side.
According to this, by forming the bearing case as an integrally formed member formed by closing the top located at one end in the axial direction of the base, it is not necessary to attach the cap later to close the top, Cost reduction can be achieved by reducing the number of parts, and the manufacturing process can be made more efficient by eliminating the step of attaching the cap later.

A bearing mounting structure according to the present invention is a bearing mounting structure for mounting a first bearing and a second bearing that support a rotating shaft inserted through a housing, the bearing mounting structure comprising: a substantially cylindrical first base; A first bearing case having a first flange formed so as to expand outward from one axial end of the base, supporting one axial end of the rotating shaft. A substantially cylindrical second base having a bearing therein, a second flange formed to extend outward from one end in the axial direction of the second base, and the second base. A second bearing case, which is an integrally formed member having no welding portion and having a closing portion that closes the top portion located on the opposite end side of the second flange portion in the axial direction, is provided with a second bearing case in the axial direction of the rotating shaft. A second bearing for supporting the other end of the bearing is provided inside, and the first bearing case is arranged so that the first flange extends along the housing. A first bearing case is welded to the housing, and the second bearing case is arranged such that the second flange portion is aligned with the housing, and the second flange portion joins the first bearing case. A bearing case is welded to the housing. Further, in the bearing mounting structure of the present invention, the peripheral edge of the first flange is continuously welded to the housing in the circumferential direction at a position separated by 3 mm or more from the root of the first flange, and the second flange is welded to the housing. The peripheral edge of the second flange is continuously welded to the housing in the circumferential direction at a position separated by 3 mm or more from the base of the flange.

A method of manufacturing the bearing mounting structure of the present invention is a method of manufacturing the bearing mounting structure of the present invention, wherein the first flange portion of the first bearing case in which the first bearing is housed is attached to the housing. and welding the second flange of the second bearing case in which the second bearing is housed to the housing. In the method of manufacturing the bearing mounting structure of the present invention, the second bearing case is formed by pressing and deforming a metal material by press working before welding the second bearing case.

INDUSTRIAL APPLICABILITY The bearing mounting structure of the present invention can greatly reduce welding heat damage to bearings, and can reliably prevent damage to bearings, deterioration of lubricants in bearings, and shortening of bearing life.

FIG. 2 is a perspective explanatory view of a closed state of an exhaust valve provided with a bearing mounting structure according to an embodiment of the present invention; FIG. 4 is a transverse explanatory diagram of an open state of an exhaust valve provided with the bearing mounting structure of the embodiment; 3(a) and 3(b) are enlarged views around the bearing and bearing case in FIG. 2; FIG. (a) is a perspective view of the bearing case in the bearing mounting structure of the embodiment as viewed from the flange side, (b) is a perspective view showing a state in which the bearing is installed in the bearing case of (a), and (c) is The perspective view which looked the bearing case of the same figure (a) from the closed part side. FIG. 4 is a longitudinal explanatory view of the open state of the exhaust valve provided with the bearing mounting structure of the embodiment, viewed from the bottom side. FIG. 4 is a longitudinal explanatory view of the closed state of the exhaust valve provided with the bearing mounting structure of the embodiment, viewed from the bottom side. FIG. 4 is a partial cross-sectional explanatory view for explaining a closed state of an exhaust valve provided with the bearing mounting structure of the embodiment;

[Exhaust valve provided with bearing mounting structure of embodiment]
An exhaust valve 1 having a bearing mounting structure according to an embodiment of the present invention is installed in an exhaust passage of an automobile through which exhaust gas flows, and adjusts the amount of exhaust gas flowing and the exhaust sound by opening and closing the valve. As shown in FIGS. 1 to 3 and 4 to 7, the exhaust valve 1 is arranged in a substantially cylindrical tubular body 2 corresponding to a housing in a direction orthogonal to the axial direction of the tubular body 2, a rotating shaft 3 penetrating through the peripheral wall 21 so as to pass through substantially the center of the tubular body 2; It has a stopper 5 fixed to.

The tubular body 2 corresponding to the housing in this embodiment connects the upstream pipe 11 and the downstream pipe 12 of the exhaust that constitute the exhaust passage. 11, a downstream pipe 12 is fixed on the other end side. The method of fixing the upstream pipe 11 and the downstream pipe 12 for the exhaust gas to the pipe body 2 is appropriate. It is fixed by butt welding, or the upstream pipe 11 is fitted to one end side of the tubular body 2 in the pipe axial direction, and the downstream pipe 12 is fitted to the other end side, and fixed by fillet welding or penetration welding. Alternatively, the upstream pipe 11 and the downstream pipe 12 are fitted to one end side of the pipe body 2 in the pipe axial direction and the downstream pipe 12 are fitted to the other end side of the pipe body 2, respectively, and fixed by fillet welding or penetration welding. is possible.

Rotating shaft insertion holes 22 and 23 are formed in the peripheral wall 21 of the tubular body 2 at positions facing each other in the radial direction. It is arranged in the tubular body 2 so that the end thereof is inserted into the rotary shaft insertion hole 23 .

A substantially hat-shaped bearing case 61 with an open top is provided outside the rotating shaft insertion hole 22 . As shown in FIG. 3A, the bearing case 61 includes a substantially cylindrical base portion 612 with an open top and a flange portion 611 extending outward from one axial end of the base portion 612. have The bearing case 61 is an integrally formed member that is integrally formed by pressing and deforming a metal material by press working or the like. It is formed by The collar portion 611 is curved to follow the outer peripheral surface of the tubular body 2 , is formed to be recessed in an arc when viewed in the axial direction of the tubular body 2 , and is arcuate in a direction perpendicular to the axial direction of the tubular body 2 . is formed so as to swell toward the tubular body 2.

A collar portion 611 formed by deforming into a shape following the outer peripheral surface of the peripheral wall 21 of the tubular body 2 is arranged along the outer peripheral surface of the peripheral wall 21 of the tubular body 2 corresponding to the housing. A flange 611 is welded and fixed to the peripheral wall 21 of the tubular body 2 at a distant outer position, and in the illustrated example, the peripheral edge of the flange 611 is fixed to the peripheral wall 21 of the tubular body 2 at a weld W1. The bearing case 61 is fixed to the tubular body 2 corresponding to the housing by fixing the flange portion 611 at the welded portion W1. The welded portion W1 can also be formed inside the peripheral edge of the flange portion 611, and is continuous in the circumferential direction of the flange portion 611 from the viewpoint of suppressing thermal deformation after welding the bearing case 61 and the tubular body 2. Also, the distance between the base of the collar portion 611 and the welded portion W1 is determined from the viewpoint of ensuring stable fixation of the bearing case 61 and the tubular body 2 and reducing the thermal effect on the bearing 71. Therefore, it is preferably 3 mm or more.

A bearing 71 for supporting the rotating shaft 3 is press-fitted into the bearing case 61 , and the bearing 71 is attached to the tubular body 2 corresponding to the housing via the bearing case 61 . The bearing 71 supports one axial end of the rotating shaft 3 protruding from the rotating shaft insertion hole 22 to the outside of the tubular body 2 .

A substantially hat-shaped bearing case 62 with a closed top is provided outside the rotating shaft insertion hole 23 . As shown in FIGS. 3(b) and 4, the bearing case 62 has a substantially cylindrical base portion 622 with an open top, and a base portion 622 extending outward from one axial end of the base portion 622. It has a collar portion 621 and a closing portion 623 that closes the top portion located on the end portion side opposite to the collar portion 621 in the axial direction of the base portion 622 . The bearing case 62 is an integrally formed member that is integrally formed by pressing and deforming a metal material by press working or the like. It is formed by The flange portion 621 is curved to follow the outer peripheral surface of the tubular body 2 , is formed to be recessed in an arc when viewed in the axial direction of the tubular body 2 , and is arcuate in a direction orthogonal to the axial direction of the tubular body 2 . is formed so as to swell toward the tubular body 2.

The collar portion 621 formed by deforming into a shape following the outer peripheral surface of the peripheral wall 21 of the tubular body 2 is arranged along the outer peripheral surface of the peripheral wall 21 of the tubular body 2 corresponding to the housing. A flange 621 is welded and fixed to the peripheral wall 21 of the tubular body 2 at a distant outer position, and in the illustrated example, the peripheral edge of the flange 621 is fixed to the peripheral wall 21 of the tubular body 2 at a weld W2. The bearing case 62 is fixed to the tubular body 2 corresponding to the housing by fixing the flange 621 at the welded portion W2. The welded portion W2 can also be formed inside the peripheral edge of the flange portion 621, and is continuous in the circumferential direction of the flange portion 621 from the viewpoint of suppressing thermal deformation after welding the bearing case 62 and the tubular body 2. Also, the distance between the base of the collar portion 621 and the welded portion W2 is determined from the viewpoint of ensuring stable fixation between the bearing case 62 and the tubular body 2 and reducing the thermal effect on the bearing 72. Therefore, it is preferably 3 mm or more.

A bearing 72 for supporting the rotating shaft 3 is press-fitted into the bearing case 62 , and the bearing 72 is attached to the tubular body 2 corresponding to the housing via the bearing case 62 . The bearing 72 supports the other end side in the axial direction of the rotating shaft 3 protruding from the rotating shaft insertion hole 23 to the outside of the tubular body 2 .

One axial end of the rotating shaft 3 protrudes outside the bearing 71 and is connected to the drive transmission portion 81 of the actuator 8 . The rotary shaft 3 is driven by the actuator 8 to rotate via a drive transmission portion 81 , and according to the rotation of the rotary shaft 3 , the valve plate opens and closes the exhaust flow path in the tubular body 2 . 4 rotates.

In the illustrated example, the valve plate 4 is formed in a substantially circular shape when viewed from the front. It has a stepped plate shape. The substantially semicircular first flat plate portion 41 and the substantially semicircular second flat plate portion 42 are arranged to extend substantially parallel to each other, and the first flat plate portion 41 is closer to the axis of the rotation shaft 3 than the second flat plate portion 42 is. It is formed long in a direction orthogonal to the direction and has a large area. A curved plate portion 43 provided between the first flat plate portion 41 and the second flat plate portion 42 is arranged substantially along the outer peripheral surface of the rotating shaft 3 and fixed to the rotating shaft 3 by welding or the like.

As shown in FIGS. 2 to 6, the stopper 5 is a substantially C-shaped integrally formed member having a base portion 51 formed with an insertion hole 511 into which the rotating shaft 3 is inserted. A substantially arc-shaped first contact portion 52 is formed on one downstream side, and a substantially arc-shaped second contact portion 53 is formed on the other upstream and downstream sides of the base portion 51 . The substantially arc-shaped first contact portion 52 extends along the inner peripheral surface 24 of the tubular body 2 , and the substantially arc-shaped second contact portion 53 extends along the inner peripheral surface 24 of the tubular body 2 . It extends in the tubular body 2 so as to extend in the opposite direction to the first contact portion 52 in the peripheral direction of the tubular body. The stopper 5 is fixed to the peripheral wall 21 of the tubular body 2 by welding such as penetration welding.

The first contact portion 52 and the second contact portion 53 of the stopper 5 are formed at positions where the valve plate 4 contacts when the rotating valve plate 4 is in a position to close the exhaust flow path of the tubular body 2. The contact surface 521 of the first contact portion 52 to the valve plate 4 and the contact surface 531 of the second contact portion 53 to the valve plate 4 close the exhaust passage of the tubular body 2. It abuts on the valve plate 4 at the position where the valve plate 4 is positioned to restrict the rotation of the valve plate 4 . FIG. 5 shows the contact between the valve plate 4, which is positioned to close the exhaust flow path of the tubular body 2, and the contact surface 521 of the first contact portion 52 and the contact surface 531 of the second contact portion 53. shows the contact area R by .

The distance L in the axial direction of the tubular body 2 between the contact surface 521 of the first contact portion 52 of the stopper 5 to the valve plate 4 and the contact surface 531 of the second contact portion 53 to the valve plate 4 is , and formed so as to be larger than the shaft diameter of the rotary shaft 3 , and the tip of the substantially arc-shaped first contact portion 52 and the tip of the substantially arc-shaped second contact portion 53 are aligned with the rotation shaft insertion hole 23 . It is arranged so as not to contact or interfere with the portion near the other end in the axial direction of the rotating shaft 3 located nearby (see FIGS. 3 and 2).

In the exhaust valve 1 of the present embodiment, the driving of the actuator 8 is controlled by the control device (not shown), and the rotation shaft 3 and the valve plate 4 are rotated to switch between the open state and the closed state. In the exhaust valve 1 in the open state, the direction in which the surfaces of the first flat plate portion 41 and the second flat plate portion 42 of the valve plate 4 extend follows the exhaust flow path in the pipe body 2 and the pipe axial direction (Fig. 2, see Figure 5). In the exhaust valve 1 in the closed state, the first flat plate portion 41 and the second flat plate portion 42 of the valve plate 4 are arranged so as to close the exhaust flow path in the tubular body 2 , and the first flat plate portion 41 is located at the first flat plate portion of the stopper 5 . The contact surface 521 of the contact portion 52 abuts, the second flat plate portion 42 contacts the abutment surface 531 of the second contact portion 53 of the stopper 5 , and the downstream pipe 12 is closed so that the exhaust gas does not flow. (see Figures 1, 6 and 7).

According to the bearing mounting structure of the present embodiment, by welding the bearing cases 61 and 62 to the tubular body 2 corresponding to the housing with the flanges 611 and 621, the distance from the welding points to the bearings 71 and 72 is increased, The amount of heat conducted to the bearings 71 and 72 inside the bearing cases 61 and 62 during welding can be reduced as much as possible, and welding heat damage to the bearings 71 and 72 can be greatly reduced. Therefore, breakage of the bearings 71 and 72, deterioration of the lubricant in the bearings 71 and 72, and reduction in the service life of the bearings 71 and 72 can be reliably prevented.

Moreover, by forming the flanges 611 and 621 of the bearing cases 61 and 62 in a curved manner so as to follow the outer peripheral surface of the peripheral wall 21 of the tubular body 2 , the bearing cases 61 and 62 are formed on the outer peripheral surface of the curved tubular body 2 . Also, when the bearings 71 and 72 are installed therein, the welding heat damage to the bearings 71 and 72 can be greatly reduced, and the bearing cases 61 and 62 are attached to the outer peripheral surface of the tubular body 2 having a curved surface. can be mounted stably and with high strength. In addition, when the tubular body 2 is an exhaust flow path, the bearing cases 61 and 62 can be installed without narrowing the cross section of the flow path by protruding into the tubular body 2, in other words, into the flow path. The flow channel performance of the body 2 can be maintained without deteriorating.

Further, by deforming and forming the flanges 611 and 621 so as to bend from one end in the axial direction of the bases 612 and 622, the bearing cases 61 and 62 can be formed by bending by press working or the like. It is possible to obtain the bearing cases 61 and 62 without performing cutting work with high processing costs, reduce the manufacturing cost of the product provided with the bearing cases 61 and 62 and the bearing mounting structure, and efficiently can be manufactured to In particular, when forming the bearing cases 61 and 62 having a shape in which the flanges 611 and 621 are curved so as to follow the outer peripheral surface of the tubular body 2 by cutting, the processing cost is considerably high and the processing time is considerably long. The bearing cases 61 and 62 having such shapes can be obtained at a very low cost and with high manufacturing efficiency.

In addition, by forming one bearing case 62 as an integrally formed member formed by closing a top portion located on one end side of the base portion 622 in the axial direction with a closing portion 623, a cap is added later to close the top portion. It is possible to reduce the number of parts and reduce the cost, and eliminate the post-attaching process of the cap, thereby improving the efficiency of the manufacturing process.

[Scope of invention disclosed in this specification]
In addition to each invention and embodiment listed as an invention, the invention disclosed in this specification is specified by changing these partial contents to other contents disclosed in this specification within the applicable range, Alternatively, what is specified by adding other contents disclosed in this specification to these contents, or what is specified by deleting these partial contents to the extent that partial effects can be obtained and making them a broader concept contain. The invention disclosed in this specification also includes the following modifications and additional content.

In the above embodiment, an example in which the bearing mounting structure of the present invention is attached to the exhaust valve 1 has been described, but the bearing mounting structure of the present invention is suitable within the scope of the present invention, and can be applied to products other than exhaust valves. It also includes those that are provided. Further, in the above embodiment, the tubular body 2 having a cylindrical outer peripheral surface is used as a preferred example of the housing, but the housing in the bearing mounting structure of the present invention may have a curved surface other than the tubular body 2. or have a planar surface.

INDUSTRIAL APPLICABILITY The present invention can be used, for example, as a bearing mounting structure for mounting a bearing that supports a rotating shaft of a valve plate provided through an exhaust passage of an automobile.

DESCRIPTION OF SYMBOLS 1... Exhaust valve 2... Pipe body 21... Peripheral wall 22, 23... Rotating shaft insertion hole 24... Inner peripheral surface 3... Rotating shaft 4... Valve plate 41... First flat plate part 42... Second flat plate part 43... Curved plate part 5 Stopper 51 Base 511 Insertion hole 52 First contact portion 521 Contact surface 53 Second contact portion 531 Contact surface 61, 62 Bearing case 611, 621 Flange 612, 622 Base 623... Closed part 71, 72... Bearing 8... Actuator 81... Drive transmission part 11... Upstream pipe 12... Downstream pipe W1, W2... Welded part R... Contact surface between valve plate and first contact part and second contact contact area due to contact with the contact surface of the part L ... distance in the tube axial direction between the contact surface of the first contact part and the contact surface of the second contact part

Claims (4)

A bearing mounting structure for mounting a first bearing and a second bearing that support a rotating shaft inserted through a housing,
A first bearing case having a substantially cylindrical first base portion and a first flange portion formed to expand outward from one axial end portion of the first base portion ; A first bearing that supports one end side in the axial direction is installed,
a substantially cylindrical second base; a second collar formed to extend outward from one end in the axial direction of the second base; A second bearing case, which is an integrally formed member having no welding portion and having a closing portion that closes the top portion located on the opposite end side to the flange portion of the rotating shaft, is provided with the other end portion in the axial direction of the rotating shaft. a second bearing supporting the side is incorporated;
The first bearing case is arranged so that the first flange portion is aligned with the housing, and the first bearing case is welded to the housing by the first flange portion ,
The second bearing case is arranged so that the second flange portion is aligned with the housing, and the first bearing case is welded to the housing by the second flange portion. bearing mounting structure. The peripheral edge of the first flange is continuously welded to the housing in the circumferential direction at a position separated by 3 mm or more from the base of the first flange,
2. The bearing mounting structure according to claim 1, wherein the peripheral edge of said second flange is continuously welded to said housing in the circumferential direction at a position separated by 3 mm or more from the base of said second flange. . A method for manufacturing a bearing mounting structure according to claim 1 or 2,
The first flange portion of the first bearing case in which the first bearing is housed is welded to the housing, and the second bearing case of the second bearing case in which the second bearing is housed is welded to the housing. A method of manufacturing a bearing mounting structure, comprising a step of welding a collar portion to the housing. 4. The method of manufacturing a bearing mounting structure according to claim 3, wherein the second bearing case is formed by pressing and deforming a metal material by press working before welding the second bearing case.