JP6469491B2 - Bush and manufacturing method thereof - Google Patents

Description

  The present invention relates to a cylindrical bush having a groove formed on an inner peripheral surface and a technique for manufacturing the bush.

  2. Description of the Related Art Conventionally, a bushing technique in which a groove is formed on an inner peripheral surface is known. For example, as described in Patent Document 1.

  Patent Document 1 describes a cylindrical bush having an inner peripheral surface (bearing surface) that supports a shaft and a groove formed on the inner peripheral surface. The groove is formed so as not to be open in the axial direction of the bush (in the middle portion in the axial direction of the bush). The groove is intended to suppress the occurrence of seizure between the bush and the shaft by holding lubricating oil in the groove.

  However, in the bush configured as described above, the groove is not formed in the vicinity of the tip in the axial direction of the bush, and therefore it is difficult to supply the lubricating oil in the vicinity of the tip. For this reason, there is a possibility that the occurrence of image sticking cannot be sufficiently suppressed.

  On the other hand, if the groove is formed so as to open in the axial direction of the bush, the lubricating oil is discharged from the inner peripheral surface, and the lubricating oil may be insufficient on the inner peripheral surface.

Special table 2012-515303 gazette

  The present invention has been made in view of the above situation, and a problem to be solved is to provide a bushing capable of suppressing the occurrence of seizure and a method for manufacturing the same.

  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, it comprises a bush main body formed in a cylindrical shape, and a groove formed on the inner peripheral surface of the bush main body, and the groove has at least one tip in the longitudinal direction, In the cross-sectional view from the longitudinal direction or the width direction intersecting the longitudinal direction, only the wall surface of the tip portion of the groove is the bushing body. These are formed so as to form an obtuse angle with respect to the inner peripheral surface.

  According to a second aspect of the present invention, the groove is formed such that the wall surface of the tip portion has a smooth rounded shape with respect to the bottom surface of the groove in a cross-sectional view from the width direction.

  According to a third aspect of the present invention, the groove is formed such that the tip end is tapered in the depth direction of the groove.

According to a fourth aspect of the present invention, the method includes a plate material preparing step of preparing a plate material, a groove forming step of forming a groove in the plate material by pressing, and a bending step of bending the plate material on which the groove is formed into a cylindrical shape. In the groove forming step, the groove is formed such that at least one tip portion in the longitudinal direction is positioned in the middle portion of the plate material in a direction that is an axial direction of the cylindrical plate material, and the longitudinal direction or in a cross-sectional view of the width direction intersecting the longitudinal direction, of the groove, in which only the wall of the tip is formed so as to form an obtuse angle with respect to the surface of the plate where the groove is formed is there.

  According to a fifth aspect of the present invention, in the groove forming step, the groove is formed such that the wall surface of the tip portion has a smooth rounded shape with respect to the bottom surface of the groove in a cross-sectional view from the width direction. Is.

  According to a sixth aspect of the present invention, in the groove forming step, the groove is formed such that the tip end is tapered in the depth direction of the groove.

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

  In the first aspect, the occurrence of image sticking can be suppressed.

  In the second aspect, the occurrence of image sticking can be suppressed.

  In Claim 3, generation | occurrence | production of image sticking can be suppressed.

  In Claim 4, generation | occurrence | production of the crack of the board | plate material in a groove | channel formation process can be suppressed.

  In Claim 5, generation | occurrence | production of the crack of the board | plate material in a groove | channel formation process can be suppressed.

  In Claim 6, generation | occurrence | production of the crack of the board | plate material in a groove | channel formation process can be suppressed.

Sectional drawing which shows the use condition of the bush which concerns on one Embodiment of this invention, and the said bush. (A) Enlarged view of the groove. (B) The BB sectional drawing. The flowchart of the manufacturing method of the bush which concerns on one Embodiment of this invention. The perspective view which shows the board | plate material in a groove | channel formation process. The perspective view which shows the board | plate material in a board | plate material cutting process. (A) Schematic which shows a 1st bending process. (B) Schematic which shows a 2nd bending process. Schematic which shows a sizing process. Sectional drawing of the groove | channel which shows the difference with a prior art.

  In the following description, the directions indicated by the arrows C, R, and S in the figure are defined as an axial direction, a radial direction, and a circumferential direction, respectively.

  First, an outline of a state in which the bush 100 according to the first embodiment of the present invention is used will be described with reference to FIG.

  The bush 100 supports a shaft member (a shaft 2 described later in the present embodiment) so as to be smoothly rotatable. The bush 100 according to the present embodiment is provided in a transmission (for example, an automatic transmission (A / T), a continuously variable transmission (CVT), etc.) provided in an automobile. The bush 100 is attached to the housing 1 of the transmission and supports the shaft 2 to be rotatable.

  The housing 1 is a member that supports various shaft members, gears, and the like provided in the transmission. The housing 1 is formed with a bearing portion 1a through which the shaft 2 can be inserted. The bearing portion 1a is formed so as to penetrate the housing 1 along the axial direction. The bearing portion 1a is formed to have a circular cross section when viewed in the axial direction.

  The bush 100 is formed in a substantially cylindrical shape. The bush 100 is fixed to the housing 1 by being fitted into the bearing portion 1 a of the housing 1.

  The shaft 2 is a member that transmits driving force by rotating. The shaft 2 is rotatably supported by the bush 100 by being inserted into the bush 100.

  Lubricating oil is supplied to the bush 100 configured in this way through an oil passage (not shown). Specifically, when the engine of the automobile is started, the oil pump is operated by the driving force of the engine. Lubricating oil is pumped by the oil pump, and the lubricating oil is supplied to the bush 100 through the oil passage.

  A lubricating oil film (oil film) is formed between the bush 100 and the shaft 2 by the lubricating oil supplied to the bush 100. The shaft 2 is rotatably supported by the bush 100 via the oil film. Further, since the bush 100 supports the shaft 2 via the oil film, it is possible to suppress the occurrence of seizure between the bush 100 and the shaft 2.

  Next, the detailed structure of the bush 100 is demonstrated using FIG.1 and FIG.2.

  As described above, the bush 100 supports the shaft 2 in a rotatable manner. The bush 100 is formed in a cylindrical shape extending in the axial direction. The bush 100 includes a bush main body 10 and a groove 20.

  The bush main body 10 constitutes the main structure of the bush 100. The bushing body 10 is formed in a cylindrical shape extending in the axial direction. An inner peripheral surface 11 is formed on the bushing body 10.

  The inner peripheral surface 11 is a surface on the inner peripheral side of the bush main body 10 formed in a cylindrical shape. The inner peripheral surface 11 supports the shaft 2 in a rotatable manner.

  The groove 20 holds lubricating oil with the shaft 2. The groove 20 is formed in a groove shape in which the inner peripheral surface 11 of the bushing body 10 is recessed. The groove 20 is formed so that the longitudinal direction is substantially in the axial direction (the longitudinal direction is slightly inclined with respect to the axial direction). Four grooves 20 are formed in total, two on one side (side visible in FIG. 1) of the inner peripheral surface 11 of the bushing body 10 and two on the other side facing the one side. One tip side of the groove 20 in the axial direction extends to the end of the bushing body 10 in the axial direction and is opened. The other tip end side in the axial direction of the groove 20 extends to a midway portion in the axial direction of the bushing main body 10 and is not opened. The four grooves 20 are arranged so that the one end side (open side) of the four grooves 20 faces one side in the axial direction and the one that faces the other side in the axial direction are alternately arranged in the circumferential direction. A bottom surface 21 and a tip portion 22 are formed in the groove 20.

  The bottom surface 21 is a surface formed at the bottom of the groove 20. The bottom surface 21 is formed at a position recessed downward from the inner peripheral surface 11 of the bushing body 10.

  The front end portion 22 is a portion near the end portion on the non-open side in the longitudinal direction of the groove 20. The distal end portion 22 is located in the middle of the bushing body 10 in the axial direction. The distal end portion 22 is formed to be tapered in the depth direction view (diameter view) of the groove 20. Specifically, the distal end portion 22 is formed in a mountain shape whose top portion is rounded into a round shape as viewed in the depth direction of the groove 20. In the present specification, “tapering” means that the distance L2 in the longitudinal direction of the groove 20 from the point at which the width of the groove 20 begins to narrow to the apex of the tip 22 is greater than half of the width L1 of the groove 20, , L2> L1 / 2 is satisfied (see FIG. 2B). A wall surface 22 a is formed at the distal end portion 22.

  The wall surface 22 a is a side wall of the distal end portion 22. That is, the wall surface 22 a is a surface that connects the inner peripheral surface 11 and the bottom surface 21 of the bushing body 10 at the distal end portion 22. The wall surface 22a is a cross-sectional view (BB cross section shown in FIG. 2A) from the width direction intersecting the longitudinal direction of the groove 20 (direction perpendicular to the longitudinal direction of the groove 20 when viewed from the depth direction of the groove 20). In view), the bush body 10 is formed to have a round shape that swells outward in the radial direction. The wall surface 22 a is formed so as to be smoothly continuous with the bottom surface 21. That is, the wall surface 22a is such that the line drawn by the bottom surface 21 is a tangent line of the round shape at the lower end point P of the round shape drawn by the wall surface 22a (see FIG. 2B) in the cross-sectional view from the width direction. It is formed.

  The wall surface 22 a is formed so as to have a gentle gradient with respect to the inner peripheral surface 11 of the bushing body 10. Specifically, the wall surface 22a is formed such that the wall surface 22a and the inner peripheral surface 11 of the bushing body 10 form an obtuse angle α in a cross-sectional view from the width direction (see FIG. 2B). Inevitably, the wall surface 22 a is formed to have a radius that is larger than the depth of the groove 20.

  With the groove 20 configured as described above, the lubricating oil can be held in a space (in the groove 20) surrounded by the groove 20 and the shaft 2. Therefore, it is possible to suppress the shortage (depletion) of the lubricating oil on the inner peripheral surface 11 of the bushing body 10. For this reason, even when the shaft 2 rotates in a state where the lubricating oil is not sufficiently supplied to the bush 100 from an oil passage (not shown), seizure occurs between the inner peripheral surface 11 of the bush main body 10 and the shaft 2. Can be suppressed. In addition, as a case where the lubricating oil is not sufficiently supplied to the bush 100, for example, immediately after the engine is started (from when the engine is started until the lubricating oil is supplied to the bush 100), or when the engine is It is assumed that the vehicle is towed without being started.

  Further, the wall surface 22a is formed so as to have a gentle slope with respect to the inner peripheral surface 11 of the bushing main body 10, so that the wall surface 22a is a groove compared to the wall surface 22a formed perpendicular to the inner peripheral surface 11. Lubricating oil retained by 20 is easily discharged out of the groove 20 along the wall surface 22a. Therefore, lubricating oil can be supplied between the inner peripheral surface 11 of the bushing main body 10 and the shaft 2 in the vicinity of both ends in the axial direction of the bushing 100. In this way, since the lubricating oil can be supplied also to the portion where the groove 20 is not formed, between the inner peripheral surface 11 of the bushing body 10 and the shaft 2 in the vicinity of both ends in the axial direction of the bushing 100. The occurrence of seizure can be suppressed.

  That is, by forming the wall surface 22 a as described above, the lubricating oil can be appropriately supplied between the inner peripheral surface 11 and the shaft 2 while holding the lubricating oil in the groove 20. Therefore, the occurrence of seizure between the inner peripheral surface 11 of the bushing main body 10 and the shaft 2 can be suppressed in the vicinity of both end portions in the axial direction of the bushing 100, and the lubricating oil is sufficiently supplied to the bushing 100. Even when the shaft 2 rotates in a state where it is not, the occurrence of seizure between the inner peripheral surface 11 of the bushing main body 10 and the shaft 2 can be suppressed.

As described above, the bush 100 according to the present embodiment includes the bush body 10 formed in a cylindrical shape and the groove 20 formed in the inner peripheral surface 11 of the bush body 10. At least one distal end portion 22 in the longitudinal direction is formed so as to be located in the middle portion in the axial direction of the bushing main body 10, and the wall surface 22a of the distal end portion 22 in a cross-sectional view from the width direction intersecting the longitudinal direction. And the inner peripheral surface 11 of the bushing main body 10 are formed so as to form an obtuse angle α.
By comprising in this way, generation | occurrence | production of image sticking can be suppressed.

The groove 20 is formed such that the wall surface 22a of the tip 22 has a smooth rounded shape with respect to the bottom surface 21 of the groove 20 in a cross-sectional view from the width direction.
By comprising in this way, generation | occurrence | production of image sticking can be suppressed.

The groove 20 is formed such that the tip 22 is tapered in the depth direction of the groove 20.
By comprising in this way, generation | occurrence | production of image sticking can be suppressed.

  Next, a method for manufacturing the bush 100 will be described with reference to FIGS.

  The manufacturing method of the bush 100 which concerns on one Embodiment of this invention comprises a board | plate material preparation process, a groove | channel formation process, a board | plate material cutting process, a bending process, and a sizing process (refer FIG. 3).

  In the plate material preparation step, the plate material 30 to be the material of the bush 100 is prepared (step S101). As the plate member 30, an appropriate flat plate material (for example, an iron-based material) is used, and for example, a coiled steel plate appropriately cut by press working is used.

  In the groove forming step shown in FIG. 4, the groove 20 is formed by press working on the plate material 30 prepared in the plate material preparing step (step S102). The groove 20 is formed to have a groove shape in which one surface of the plate member 30 (a surface that becomes the inner peripheral surface 11 of the bushing body 10, hereinafter referred to as the inner peripheral surface 11) is recessed. The groove 20 is formed so that the longitudinal direction is substantially in the axial direction (direction to be) (the longitudinal direction is slightly inclined with respect to the axial direction). One tip side in the axial direction of the groove 20 extends to the end in the axial direction of the plate member 30 and is opened. The other tip end side in the axial direction of the groove 20 extends to a midway portion in the axial direction of the plate member 30 and is not opened. The grooves 20 are arranged so that the one end side (opening side) of the groove 20 faces one side in the axial direction and the one end side of the groove 20 faces the other side of the axial direction are alternately arranged in the circumferential direction.

  The groove 20 is formed such that the front end portion 22 is located in the middle of the plate member 30 in the axial direction. The distal end portion 22 is formed to be tapered in the depth direction view (diameter view) of the groove 20. As shown in FIG. 2B, the wall surface 22a has a gentle gradient with respect to the inner peripheral surface 11 in the cross-sectional view from the width direction intersecting the longitudinal direction of the groove 20 (inside the wall surface 22a and the bushing body 10). The peripheral surface 11 forms an obtuse angle α). The wall surface 22 a is formed so as to be smoothly continuous with the bottom surface 21.

  Here, when the groove 20 is formed by press working in the groove forming step, a portion (meat) around the groove 20 of the plate member 30 is pulled toward the groove 20 side. If the pulled amount (volume) is large, the plate 30 is cracked or chipped.

  In the present embodiment, in the groove forming step, the groove 20 is formed so that the wall surface 22a of the distal end portion 22 has a gentle slope with respect to the inner peripheral surface 11 of the bushing main body 10 (obtuse angle α) as described above. To be formed. For this reason, when the groove 20 is formed by press working, the amount of the plate material 30 crushed at the tip 22 of the groove 20 is compared with that in which the wall surface 22 a is formed perpendicular to the inner peripheral surface 11. Thus, the area becomes smaller by the area D shown in FIG. Accordingly, the amount of meat around the front end portion 22 of the plate member 30 pulled toward the groove 20 is also reduced by the area D.

  As described above, according to the groove forming step of the present embodiment, the amount of meat of the plate member 30 pulled toward the groove 20 can be reduced, so that occurrence of cracks and chipping of the plate member 30 can be suppressed. In addition, in FIG. 8, the hatching which shows a cross section is abbreviate | omitted.

  Further, in the tip portion 22 of the groove 20, the portion close to the boundary with the inner peripheral surface 11 has a radial direction when the groove 20 is formed as compared with the case where the wall surface 22 a is formed perpendicular to the inner peripheral surface 11. Small displacement. Therefore, the meat of the plate 30 around the tip 22 is not pulled greatly. For this reason, generation | occurrence | production of the crack of the board | plate material 30 and a chip | tip can be suppressed.

  Further, as described above, the front end portion 22 of the groove 20 is formed to be tapered in the depth direction view of the groove 20. For this reason, when forming the groove | channel 20 by press work, the quantity of the board | plate material 30 pulled to the groove | channel 20 side becomes small compared with what the front-end | tip part 22 was formed in semicircle shape, for example. As described above, according to the groove forming step of the present embodiment, the amount of meat of the plate member 30 pulled toward the groove 20 can be reduced, so that occurrence of cracks and chipping of the plate member 30 can be suppressed.

  In the plate material cutting step shown in FIG. 5, the plate material 30 in which the groove 20 is formed is cut by press working (step S103). The cutting of the plate material 30 is performed by pressing the mold in the radial direction. In the plate material cutting step, the plate material 30 is cut into a rectangular shape which is a material for one bush 100.

  In the bending step shown in FIG. 6, the plate 30 cut in the plate cutting step is bent into a cylindrical shape. The bending process is divided into a first bending process (step S104) shown in FIG. 6A and a second bending process (step S105) shown in FIG. 6B.

  In the first bending step shown in FIG. 6A, both end portions in the circumferential direction of the plate material 30 are pressed toward the inner peripheral surface 11 side, thereby toward the center side in the circumferential direction of the plate material 30 (FIG. 6). Bend in the direction of the arrow shown in (a). As a result, the plate member 30 is substantially U-shaped with one side opened.

  In the second bending step shown in FIG. 6B, the substantially U-shaped plate material 30 is bent into a cylindrical shape. By pressing the tip portion of the plate member 30 toward the inner peripheral surface 11 side of the plate member 30, the plate member 30 bent into a substantially U shape is further bent toward the inner peripheral surface 11 side of the plate member 30. As a result, a cylindrical bush 100 in which both end portions abut each other is obtained.

  In the sizing process shown in FIG. 7, the roundness of the outer peripheral surface of the bush 100 is improved (step S106). In the sizing process, a die 40 is used. The die 40 is formed in a cylindrical shape, and the cross section of the inner periphery thereof is processed into a highly accurate perfect circle. In this sizing process, the bush 100 is passed inside the die 40. Thereby, the bush 100 with improved roundness of the outer peripheral surface is obtained.

  If necessary, the inner peripheral surface 11 of the bush 100 is also sized to obtain a bush 100 having a desired inner diameter.

  The bush 100 can be manufactured through the above steps.

As described above, in the method for manufacturing the bush 100 according to the present embodiment, the plate material preparing step for preparing the plate material 30, the groove forming step for forming the groove 20 in the plate material 30 by pressing, and the groove 20 are formed. A bending step of bending the plate material 30 into a cylindrical shape, and in the groove forming step, the groove 20 has a direction in which at least one tip portion 22 in the longitudinal direction is an axial direction of the cylindrical plate material 30. The wall surface 22a of the tip portion 22 and the inner peripheral surface 11 of the bushing body 10 are formed in a cross-sectional view from the width direction intersecting the longitudinal direction. The obtuse angle α is formed.
By comprising in this way, generation | occurrence | production of the crack of the board | plate material 30 in a groove | channel formation process can be suppressed.

Further, in the groove forming step, the groove 20 is formed so that the wall surface 22a of the tip end portion 22 has a smooth rounded shape with respect to the bottom surface 21 of the groove 20 in a cross-sectional view from the width direction. It is what is done.
By comprising in this way, generation | occurrence | production of the crack of the board | plate material 30 in a groove | channel formation process can be suppressed.

In the groove forming step, the groove 20 is formed such that the tip 22 is tapered in the depth direction of the groove 20.
By comprising in this way, generation | occurrence | production of the crack of the board | plate material 30 in a groove | channel formation process can be suppressed.

  The 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, the bush 100 according to this embodiment is provided in a transmission of an automobile, but the present invention is not limited to this. That is, the bush according to the present invention can be used for any application.

  Further, in the present embodiment, the groove 20 is formed so as to be opened only with respect to the bushing body 10 on one tip side in the axial direction (the other tip side in the axial direction is not opened). However, the present invention is not limited to this. The groove 20 may be formed so as not to be open on both ends in the axial direction with respect to the bushing body 10 (that is, the tip 22 is formed at both ends in the longitudinal direction of the groove 20). It is.

  Further, in the present embodiment, the grooves 20 are arranged such that the opening side facing the one side in the axial direction and the groove facing the other side in the axial direction are alternately arranged in the circumferential direction. The present invention is not limited to this. The groove 20 whose open side faces one side in the axial direction and the groove 20 whose open side faces the other side in the axial direction may be arranged in an appropriate order. Further, the groove 20 may be only the groove whose open side faces one side (or the other side) in the axial direction.

  In this embodiment, four grooves 20 are formed in the bush 100. However, the number of the grooves 20 is not limited and may be appropriately formed.

  Moreover, in this embodiment, although the groove | channel 20 shall be formed in linear form, this invention is not limited to this. For example, the groove 20 may be formed in a curved shape, or may be branched so that a plurality of tip portions 22 are formed.

  In the present embodiment, the bush 100 is formed by bending the flat plate member 30 into a cylindrical shape, but the present invention is not limited to this, and can be formed by various methods.

  In the present embodiment, the plate member 30 is cut after the groove 20 is formed. However, the groove 20 can be formed after the plate member 30 is cut.

  Moreover, in this embodiment, although the sizing process is performed, the said sizing process does not necessarily have to be performed.

DESCRIPTION OF SYMBOLS 10 Bush main body 11 Inner peripheral surface 20 Groove 21 Bottom 22 Front end 22a Wall 30 Plate material 100 Bush

Claims (6)

A bush body formed in a cylindrical shape;
A groove formed on the inner peripheral surface of the bushing body;
Comprising
The groove is
At least one tip portion in the longitudinal direction is formed so as to be located in the middle portion in the axial direction of the bush body,
In the cross-sectional view from the longitudinal direction or the width direction intersecting the longitudinal direction, only the wall surface of the tip portion of the groove is formed so as to form an obtuse angle with respect to the inner peripheral surface of the bush body.
Bush. The groove is
The wall surface of the tip is formed to have a smooth rounded shape with respect to the bottom surface of the groove in a cross-sectional view from the width direction.
The bush according to claim 1. The groove is
The tip is formed to be tapered in the depth direction of the groove;
The bush according to claim 1 or claim 2. A plate material preparation step of preparing a plate material;
A groove forming step of forming grooves in the plate material by press working;
A bending step of bending the plate in which the groove is formed into a cylindrical shape;
Comprising
In the groove forming step, the groove is
At least one tip portion in the longitudinal direction is formed so as to be located in the middle of the plate material in the direction that is the axial direction of the cylindrical plate material,
In a cross-sectional view of the width direction intersecting the longitudinal direction or the longitudinal direction, wherein one of the grooves, only the wall surface of the tip portion is formed so as to form an obtuse angle with respect to the surface of the plate where the groove is formed The
Bush manufacturing method. In the groove forming step, the groove is
The wall surface of the tip is formed to have a smooth rounded shape with respect to the bottom surface of the groove in a cross-sectional view from the width direction.
The method for manufacturing a bush according to claim 4. In the groove forming step, the groove is
The tip is formed to be tapered in the depth direction of the groove;
The bushing manufacturing method according to claim 4 or 5.

Images