JP6444326B2 - Joining structure of shaft and bearing member - Google Patents

Description

  The present invention relates to a joining structure between a shaft side and a bearing member side having a hole (hole) and a joining method in a technology for joining objects.

  As a background art in this technical field, a technique described in Japanese Patent Application Laid-Open No. 2014-92318 (Patent Document 1) is known. Patent Document 1 discloses a glow plug having a housing and an outer cylinder as joining objects. The glow plug includes a heater that generates heat when energized, a cylindrical shape having a cylindrical hole that penetrates in the axial direction along the axis of the glow plug, an outer cylinder that holds the heater in the cylindrical hole, and the axial direction. And a housing formed by press-fitting the outer cylinder into the inner side of the shaft hole from the front end side thereof, and holding the heater via the outer cylinder. At least one of the outer peripheral pressure contact surface of the outer cylinder and the inner peripheral pressure contact surface of the shaft hole has a recess forming region in which a recess for holding a lubricant that reduces friction during press-fitting is formed in the axial direction, A recess non-formation region that is in close contact with the pressure contact surface.

JP 2014-92318 A

  The glow plug of Patent Document 1 has a joint structure in which the housing serves as a bearing portion (bearing member), the outer cylinder serves as a shaft portion inserted into the bearing portion, and the shaft portion and the bearing portion are joined by press-fitting.

  In the above joint structure, the lubricant held in the recessed portion forming region protrudes to a portion other than the pressure contact surface (contact surface) at the time of press-fitting, or the lubricant held in the recessed portion forming region is supplied deeply into the bearing portion. There was not enough consideration for this.

  An object of the present invention is to provide a joint structure between a shaft portion and a bearing portion that can suppress the protrusion of the lubricant to a portion other than the pressure contact surface and can supply the lubricant deep into the bearing portion.

In order to achieve the above object, the joint structure of the shaft and the bearing member of the present invention is
In a joint structure of a shaft and a bearing member, which includes a shaft and a bearing member having a hole, and joins the shaft and the bearing member by press-fitting the shaft into the hole.
The shaft is disposed on at least one of the outer peripheral surface of the shaft and the inner peripheral surface of the hole at a position spaced in the press-fitting direction of the shaft when the shaft is press-fitted into the hole. A first groove provided on the side of the inlet opening for press-fitting, and a second groove provided on the side away from the inlet opening with respect to the first groove,
The area of the cross section perpendicular to the extending direction of the first groove and the area of the cross section perpendicular to the extending direction of the second groove were set to different sizes.

  According to the present invention, it is possible to provide a joint structure between a shaft portion and a bearing portion that can prevent the lubricant from protruding to a portion other than the pressure contact surface and supply the lubricant to the innermost portion of the bearing portion. it can. Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments.

FIG. 3 is an external perspective view (when unfolded) showing the joint structure between the shaft portion and the bearing portion according to the first embodiment. The external appearance perspective view which shows the joining structure of the axial part which concerns on Example 1, and a bearing part (after assembly | attachment). Sectional drawing which shows the joining structure of the axial part which concerns on Example 1, and a bearing part (at the time of expansion | deployment). Sectional drawing which shows the joining structure of the axial part which concerns on Example 1, and a bearing part (in the middle of an assembly | attachment). Sectional drawing which shows the joining structure of the axial part which concerns on Example 1, and a bearing part (after assembly | attachment). The enlarged view of the groove part in the joining structure of the axial part which concerns on Example 1, and a bearing part. The figure explaining the lubricant application state in the junction structure of the shaft part and bearing part concerning Example 1 (figure showing the state where slot 12 is located near opening 6). The figure explaining the lubricant application state in the junction structure of the shaft part and bearing part concerning Example 1 (the figure showing the state where the lubricant is applied from groove 11 and groove 12). The figure explaining the lubricant application state in the junction structure of the shaft part and bearing part concerning Example 1 (after press-fitting). The external appearance perspective view which shows the joining structure of the axial part which concerns on Example 2, and a bearing part (at the time of expansion | deployment). The external appearance perspective view which shows the joining structure of the axial part which concerns on Example 2, and a bearing part (after assembly | attachment). Sectional drawing which shows the joining structure of the axial part which concerns on Example 2, and a bearing part (at the time of expansion | deployment). Sectional drawing which shows the junction structure of the axial part which concerns on Example 2, and a bearing part (in the middle of an assembly | attachment). Sectional drawing which shows the junction structure of the axial part which concerns on Example 2, and a bearing part (after assembly | attachment). The enlarged view of the groove part in the joining structure of the axial part which concerns on Example 2, and a bearing part. The figure explaining the lubricant application state in the joining structure of the shaft part and bearing part which concerns on Example 2 (The figure which shows the state in which the insertion direction front-end | tip 31 of the shaft part 19 is located in the vicinity of the groove | channel 30). The figure explaining the lubricant application state in the junction structure of the shaft part and bearing part concerning Example 2 (the figure showing the state where the lubricant is applied from groove 29 and groove 30). The figure explaining the lubricant application state in the junction structure of the shaft part and bearing part concerning Example 2 (after press-fitting). The external appearance perspective view which shows the joining structure of the axial part which concerns on Example 3, and a bearing part (at the time of expansion | deployment). The external appearance perspective view which shows the joining structure of the axial part which concerns on Example 3, and a bearing part (after assembly | attachment). Sectional drawing which shows the joining structure of the axial part which concerns on Example 3, and a bearing part (at the time of expansion | deployment). Sectional drawing which shows the joining structure of the axial part which concerns on Example 3, and a bearing part (in the middle of an assembly | attachment). Sectional drawing which shows the joining structure of the axial part and bearing part which concern on Example 3 (after assembly | attachment). The enlarged view of the groove part in the joining structure of the axial part which concerns on Example 3, and a bearing part. The figure explaining the lubricant application state in the junction structure of the shaft part and bearing part concerning Example 3 (state immediately after shaft part 37 was inserted in hole 38 of a bearing part, and shaft side groove 42 passed bearing side groove 44 Figure showing). The figure explaining the lubricant application state in the joint structure of the shaft part and the bearing part according to Example 3 (the shaft side groove 42 in the shaft part 37 in the middle of press-fitting and the bearing side groove 44 in the hole 38 to the center contact part 52 The figure which shows that the lubricants 50 and 51 are supplied). The figure explaining the lubricant application state in the junction structure of the shaft part and bearing part concerning Example 3 (after press-fitting). The external appearance perspective view which shows the joining structure of the axial part which concerns on Example 4, and a bearing part (at the time of expansion | deployment). The external appearance perspective view which shows the joining structure of the axial part which concerns on Example 4, and a bearing part (after assembly | attachment). Sectional drawing which shows the junction structure of the axial part which concerns on Example 4, and a bearing part (at the time of expansion | deployment). Sectional drawing which shows the junction structure of the axial part which concerns on Example 4, and a bearing part (in the middle of an assembly | attachment). Sectional drawing which shows the junction structure of the axial part which concerns on Example 4, and a bearing part (after assembly | attachment). The enlarged view of the groove part in the joining structure of the axial part which concerns on Example 4, and a bearing part. The figure explaining the lubricant application state in the joint structure of the shaft part and the bearing part according to Example 4 (a state immediately after the shaft part 53 is inserted into the hole 54 of the bearing part and the shaft side groove 58 passes through the bearing side groove 60. Figure showing). The figure explaining the lubricant application state in the junction structure of the shaft part and bearing part concerning Example 4 (the shaft side groove 58 in the shaft part 53 in the middle of press-fitting, and the bearing side groove 60 in the hole 54, to the center contact part 62 The figure which shows that the lubricants 50 and 51 are supplied). The figure explaining the lubricant application state in the junction structure of the shaft part and bearing part concerning Example 3 (after press-fitting).

  Embodiments according to the present invention will be described below with reference to the drawings. The vertical direction used in the following description is based on the vertical direction in the drawings to be referred to, and the vertical direction when the shaft portion and the bearing portion are assembled and the joint structure between the shaft portion and the bearing portion are products. It has nothing to do with the vertical direction when mounted on.

  FIG. 1 is an external perspective view (when unfolded) showing a joint structure between a shaft portion and a bearing portion according to the first embodiment.

  The shaft (shaft portion) 1 has a cylindrical or columnar shape and is made of a martensitic stainless steel material. The shaft 1 is attached to, for example, a relief valve that is a part used in a high-pressure fuel pump, and is used as a stopper for fixing a spring. The bearing member (bearing portion) 3 has a cylindrical shape and is made of an austenitic stainless steel material. The bearing member 3 includes a hole (hole) 2 for press-fitting the shaft 1, and an inner wall (inner peripheral surface) 2 b of the hole 2 constitutes a bearing surface. The hole 2 is formed from the end face 3 a of the bearing member 3 in the insertion direction of the shaft 1 (in the direction of the central axis 1 a of the shaft 1) 7. The groove 10 (10a, 10b) is formed on the outer peripheral surface 1b of the shaft 1. The shape and the like of the groove 10 will be described in detail later. The opening 6 is formed as an opening surface of the hole 2 in the end surface 3 a of the bearing member 3, and serves as an inlet for inserting the shaft 1 into the hole 2.

  FIG. 2 is an external perspective view (after assembly) showing a joint structure between the shaft portion and the bearing portion according to the first embodiment.

  The contact surface (contact portion or contact region) 5 is a region where the outer peripheral surface 1 b of the shaft 1 and the inner wall 2 b of the hole 2 are in contact with each other. The direction 7 is parallel to the central axis 1a of the shaft 1 and the central axis 2a of the hole 2, and is parallel to the insertion direction of the shaft 1. The direction 7 is a direction away from the opening 6 and along the contact surface 5 (a direction parallel to the contact surface 5). The shaft 1 is inserted into the hole 2 from the opening 6 along the direction 7.

  FIG. 3 is a cross-sectional view (when unfolded) illustrating the joint structure between the shaft portion and the bearing portion according to the first embodiment. FIG. 4 is a cross-sectional view (in the middle of assembly) illustrating the joint structure between the shaft portion and the bearing portion according to the first embodiment. FIG. 5 is a cross-sectional view (after assembling) illustrating a joint structure between the shaft portion and the bearing portion according to the first embodiment.

  In this embodiment, the hole 2 is formed in a bottomed cylindrical shape, and the innermost part of the hole 2 (inner wall 2b) is closed by the bottom (bottom surface) 2c. A chamfered portion 2 d is formed in the opening 6 of the hole 2. The present embodiment relates to the joint structure between the shaft 1 and the bearing member 3, and the contact area between the outer peripheral surface 1b of the shaft 1 and the inner wall 2b of the hole 2 is important. A description will be given with the opening 6 as the starting end of the inner wall 2b where the contact with the inner wall 2b begins. That is, the opening 6 is located on the back side of the hole 2 with respect to the chamfered portion 2d.

  A chamfered portion 1d is formed at a corner where the tip surface 1c and the outer peripheral surface 1b intersect at the end of the shaft 1 in the insertion direction. In addition, about the dimension of the length direction of the axis | shaft 1, it is not necessarily restricted to the length shown in figure, Various length can be taken.

  In this embodiment, as shown in FIG. 5, after the shaft 1 is assembled to the bearing member 3, the tip surface 1 c of the shaft 1 is in contact with the bottom surface 2 c of the hole 2. The joint structure of the shaft 1 and the bearing member 3 in the present embodiment can also be employed in a configuration in which the tip surface 1c of the shaft 1 does not contact the bottom surface 2c of the hole 2.

  In this embodiment, the hole (hole) 2 may be either a hole (hole) penetrating the bearing member or a hollow hole (hole) having a bottom surface. The same applies to the following embodiments.

  FIG. 6 is an enlarged view of the groove portion in the joint structure between the shaft portion and the bearing portion according to the first embodiment.

  In this embodiment, the groove 10 (10a, 10b) is formed on the outer peripheral surface 1b of the shaft 1. On the outer peripheral surface 1b of the shaft 1, a groove 10b is formed on the lower side (the tip 1c side of the shaft 1), and a groove 10a is formed on the upper side (the base end 1e side of the shaft 1). That is, after assembling the shaft 1 to the bearing member 3, the groove 10 b is located on the back side of the hole 2 and the groove 10 a is located on the opening 6 side of the hole 2 when viewed from the opening 6 side.

  In the present embodiment, the cross-sectional shape perpendicular to the longitudinal direction (extending direction) of the groove 10 is a triangular shape. The width W and depth D of the groove 10b are defined as shown in FIG. The width and depth of the groove 10a are also defined in the same manner as the width W and depth D of the groove 10b. The width W and depth D of the grooves 10a and 10b will be described later.

  The cross-sectional shape of the groove is not limited to a triangular shape, but may be a semicircle, a semi-ellipse, a part of a circle connected to a taper, a rectangle, a triangle, or other shapes.

  FIG. 7 is a view for explaining a lubricant application state in the joint structure between the shaft portion and the bearing portion according to the first embodiment (a view showing a state where the groove 12 is positioned in the vicinity of the opening 6). In FIG. 7, the amount (distribution) of the lubricant 15 on the contact surface 5 is schematically shown.

  As the groove 10 b is inserted and moved inside the hole 2, the lubricant 15 held in the groove 10 b is applied to the outer peripheral surface 1 b of the shaft 1 and the inner wall 2 b of the hole 2 and spreads to the contact surface 5. When the shaft 1 is displaced relative to the bearing member 3 (the inner peripheral surface 2b of the hole 2) and is inserted (press-fitted) toward the inner side of the hole 2, the lubricant 15 is moved along the direction 7. It is pushed down toward the back side of the hole 2. In the initial contact portion 13 of the bearing member 3 that contacts the shaft 1 in the initial stage when the shaft 1 is inserted into the hole 2, the lubricant 15 is removed as the shaft 1 is inserted into the inner side of the hole 2. 2, the amount of the lubricant 15 is reduced.

  Therefore, the groove 10a is formed on the base end 1e side of the shaft 1 with respect to the groove 10b formed in the vicinity of the distal end portion 1c of the shaft 1, and the lubricant 18 is held in the groove 10a. The groove 10a and the groove 10b are spaced apart in the direction along the central axis 1a of the shaft 1, and the groove 10b is located on the tip 1c side of the shaft 1 with respect to the groove 10a. As a result, when the lubricant 15 in the initial contact portion 13 is reduced to the point immediately before it disappears, the lubricant 18 is newly supplied from the groove 10a to the initial contact portion 13, and seizure between the shaft 1 and the bearing member 3 can be prevented. .

  The width W of the groove 10b is set to such an extent that the surface pressure does not decrease, and the depth D of the groove 10b is set to such an extent that the strength required for the shaft does not decrease. The relationship between the width W and the depth D is set so that the lubricant 15 does not protrude.

  Note that the lubricant 15 and the lubricant 18 may be made of the same material or different materials.

  FIG. 8 is a view for explaining the state of application of the lubricant in the joint structure between the shaft portion and the bearing portion according to the first embodiment (a view showing a state in which the lubricant is applied from the grooves 11 and 12). In FIG. 8, the amounts (distribution) of the lubricants 15 and 18 on the contact surface 5 are schematically shown.

  In this embodiment, the width W and the depth D of the groove 10a are smaller than the width W and the depth D of the groove 10b. Alternatively, either the width W or the depth D of the groove 10a is made smaller than the groove 10b. That is, the volume (cross-sectional area) of the groove 10a is made smaller than the volume (cross-sectional area) of the groove 10b. Thereby, the amount of the lubricant 15 that can be held by the groove 10a is smaller than the amount of the lubricant 18 that can be held by the groove 10b. The width W and the depth D of the groove 10a may be dimensions that can hold the lubricant 18 in such an amount that no seizure occurs on the contact surface 5 from the groove 10a to the other end (base end portion) 1e of the shaft.

  FIG. 9 is a diagram (after press-fitting) illustrating the state of lubricant application in the joint structure between the shaft portion and the bearing portion according to the first embodiment.

  In the present embodiment, the lubricant 15 supplied from the groove 10 b to the initial contact portion 13 is pushed down toward the back side of the hole 2 and lubricated from the groove 10 a to the initial contact portion 13 before depletion from the initial contact portion 13. Agent 18 is supplied. Thereby, the lubricant 18 is applied to at least the contact surface 5 on the opening 6 side from the groove 10b, and the lubricants 15 and 18 are applied to the contact surface 5 in the whole direction along the central axes 1a and 2a. A state is realized.

  In the present embodiment, the grooves 10a and 10b are spaced apart in the direction along the central axis 1a of the shaft 1 so that the amount of the lubricants 15 and 18 held in the grooves 10a and 10b can be reduced. Can be reduced. As a result, the protrusion of the lubricants 15 and 18 when the grooves 10a and 10b are inserted (press-fitted) into the holes 2 can be reduced.

  In particular, the lubricant 15 that protrudes from the groove 10b toward the front end surface 1c of the shaft 1 is accumulated between the front end surface 1c and the bottom surface 2c of the hole 2 until the front end surface 1c of the shaft 1 contacts the bottom surface 2c of the hole 2. This is a factor that hinders insertion (press-fit) of the shaft 1 into the bearing member 3. Therefore, in the joint structure between the shaft 1 and the bearing member 3 as in this embodiment, the protrusion of the lubricants 15 and 18 can be reduced, and a good joint structure can be realized.

  Further, in this embodiment, the grooves 10a and 10b are formed on the shaft 1 side, and the grooves 10a and 10b can be easily processed as compared with the case where the grooves 10a and 10b are formed on the bearing member 3 side. it can. In particular, when the inner diameter (diameter) of the hole 2 of the bearing member 3 is small, it is difficult to process the grooves 10a and 10b.

  Further, in this embodiment, the groove 10 is formed on the shaft 1 side, so that the amount of lubricant that protrudes toward the back side of the hole 2 when the shaft 1 is press-fitted can be reduced.

  The present embodiment includes a shaft 19 and a bearing member 21 that forms a hole 20 for press-fitting the shaft 19. In a contact surface (contact portion or contact region) 23 which is a region where the inner peripheral surface 20b of the hole 20 of the bearing member 21 and the outer peripheral surface 19b of the shaft 19 are in contact with each other along the direction 25 away from the opening 24 of the hole 20, The shaft structure has a groove 28 (28a, 28b) in which at least one of the width W and the depth D is reduced. In this embodiment, the groove 28 (28a, 28b) is formed in the bearing member 21.

  FIG. 10 is an external perspective view (when unfolded) showing the joint structure between the shaft portion and the bearing portion according to the second embodiment.

  The shaft (shaft portion) 19 has a cylindrical or columnar shape and is made of a martensitic stainless steel material. The shaft 19 is attached to, for example, a relief valve that is a part used in a high-pressure fuel pump, and is used as a stopper for fixing a spring. The bearing member (bearing portion) 21 has a cylindrical shape and is made of an austenitic stainless steel material. The bearing member 3 includes a hole (hole) 20 for press-fitting the shaft 19, and an inner wall (inner peripheral surface) 20 b of the hole 20 constitutes a bearing surface. The hole 20 is formed from the end surface 21 a of the bearing member 21 in the insertion direction of the shaft 19 (in the direction of the central axis 19 a of the shaft 19) 25. The grooves 28 (28a, 28b) are formed in the inner peripheral surface 20b of the hole 20. The shape and the like of the groove 28 will be described in detail later. The opening 24 is formed in the end surface 21 a of the bearing member 21 as an opening surface of the hole 20, and serves as an inlet for inserting the shaft 19 into the hole 20.

  FIG. 11 is an external perspective view (after assembly) showing a joint structure between the shaft portion and the bearing portion according to the second embodiment.

  The contact surface (contact portion or contact region) 23 is a region where the inner peripheral surface 22 of the hole 20 and the outer peripheral surface 19 b of the shaft 19 are in contact with each other. The direction 25 is parallel to the central axis 19 a of the shaft 19 and the central axis 20 a of the hole 20, and parallel to the insertion direction of the shaft 19. The direction 25 is a direction away from the opening 24 and along the contact surface 23 (a direction parallel to the contact surface 23). The shaft 19 is inserted into the hole 20 from the opening 24 along the direction 25.

  FIG. 12 is a cross-sectional view (when unfolded) showing the joint structure between the shaft portion and the bearing portion according to the second embodiment. FIG. 13 is a cross-sectional view (during assembly) illustrating a joint structure between the shaft portion and the bearing portion according to the second embodiment. FIG. 14 is a cross-sectional view (after assembly) showing a joint structure between the shaft portion and the bearing portion according to the second embodiment.

  In this embodiment, the hole 20 is formed in a bottomed cylindrical shape, and the innermost part of the hole 20 (inner wall 20b) is closed by the bottom (bottom surface) 20c. A chamfered portion 20 d is formed in the opening 24 of the hole 20. The present embodiment relates to the joint structure between the shaft 19 and the bearing member 21, and the contact area between the outer peripheral surface 19b of the shaft 19 and the inner wall 20b of the hole 20 is important. A description will be given using the opening 24 as the starting end of the inner wall 20b where the contact with the inner wall 20b begins. That is, the opening 24 is positioned on the back side of the hole 20 with respect to the chamfered portion 20d.

  A chamfered portion 19d is formed at a corner portion where the distal end surface 19c and the outer peripheral surface 19b intersect at the end of the shaft 19 on the distal end side in the insertion direction. In addition, about the dimension of the length direction of the axis | shaft 19, it is not necessarily restricted to the length shown in figure, Various length can be taken.

  In the present embodiment, as shown in FIG. 14, the end surface 19 c of the shaft 19 is in contact with the bottom surface 20 c of the hole 20 after the shaft 19 is assembled to the bearing member 21. The joint structure of the shaft 19 and the bearing member 21 in the present embodiment can also be employed in a configuration in which the tip end surface 19c of the shaft 19 does not contact the bottom surface 20c of the hole 20.

  FIG. 15 is an enlarged view of a groove portion in the joint structure between the shaft portion and the bearing portion according to the second embodiment.

  In this embodiment, the groove 28 (28a, 28b) is formed on the inner peripheral surface 20b of the hole 20. On the inner peripheral surface 22 of the hole 20, a groove 28b is formed on the lower side (the back side of the hole 20, that is, the side far from the opening 24), and a groove 28a is formed on the upper side (the inlet side of the hole 20, that is, the side close to the opening 24). ing.

  In the present embodiment, the cross-sectional shape perpendicular to the longitudinal direction (extending direction) of the groove 28 is a triangular shape. The width W and depth D of the groove 28a are defined as shown in FIG. The width and depth of the groove 28b are also defined in the same manner as the width W and depth D of the groove 28a. The width W and depth D of the grooves 28a and 28b will be described later.

  The cross-sectional shape of the groove is not limited to a triangular shape, but may be a semicircle, a semi-ellipse, a part of a circle connected to a taper, a rectangle, a triangle, or other shapes.

  FIG. 16 is a diagram for explaining a lubricant application state in the joint structure between the shaft portion and the bearing portion according to the second embodiment (a diagram showing a state in which the distal end 31 in the insertion direction of the shaft portion 19 is located in the vicinity of the groove 30). is there. In FIG. 16, the amount (distribution) of the lubricant 32 on the contact surface 23 is schematically shown.

  When the tip end portion of the shaft 19 is inserted and moved inside the hole 20, the lubricant 32 held in the groove 28a is applied to the inner peripheral surface 20b of the hole 20 and the outer wall (outer peripheral surface) 19b of the shaft 19, It spreads to the contact surface 23. When the shaft 19 is relatively displaced with respect to the bearing member 21 (the inner peripheral surface 20b of the hole 20) and is inserted (press-fitted) toward the inner side of the hole 20, the lubricant 32 extends along the direction 25. It is pushed down toward the back side of the hole 20. In the initial contact portion 34 of the shaft 19 that contacts the inner peripheral surface 20b of the hole 20 at the initial stage when the shaft 19 is inserted into the hole 20, the lubricant 32 is not replenished. The amount of lubricant 32 decreases as it is inserted into

  Therefore, a groove 28b is formed on the back side of the hole 20 with respect to the groove 28a formed in the vicinity of the opening 24 of the hole 20, and the lubricant 35 is held in the groove 28b. When the amount of the lubricant 32 in the initial contact portion 34 decreases to the point immediately before it runs out, the lubricant 35 is replenished to the initial contact portion 34 from the groove 28b. The groove 28a and the groove 28b are spaced apart from each other in the direction along the central axis 20a of the hole 20, and the groove 28b is located on the back side of the hole 20 with respect to the groove 28a. By newly supplying the lubricant 35 to the initial contact portion 34 from the groove 28b, seizure between the hole 20 and the shaft 19 can be prevented.

  The width W of the groove 28a is set to such an extent that the surface pressure does not decrease, and the depth D of the groove 28b is set to such an extent that the strength required for the shaft does not decrease. The relationship between the width W and the depth D is set so that the lubricant 32 does not protrude.

  Note that the lubricant 32 and the lubricant 35 may be made of the same material or different materials.

  FIG. 17 is a diagram for explaining a lubricant application state in the joint structure between the shaft portion and the bearing portion according to the second embodiment (a diagram showing a state in which the lubricant is applied from the groove 29 and the groove 30). In FIG. 17, the amounts (distribution) of the lubricants 32 and 35 on the contact surface 23 are schematically shown.

  In this embodiment, the width W and depth D of the groove 28b are smaller than the width W and depth D of the groove 28a. Alternatively, either the width W or the depth D of the groove 28b is made smaller than the groove 28a. That is, the volume (cross-sectional area) of the groove 28b is made smaller than the volume (cross-sectional area) of the groove 28a. Accordingly, the amount of the lubricant 35 that can be held by the groove 28b is smaller than the amount of the lubricant 32 that can be held by the groove 28a. The width W and the depth D of the groove 28b are dimensions that can hold the lubricant 35 in such an amount that no seizure occurs on the contact surface 23 from the groove 28b to the position where the tip 19c of the shaft 19 reaches after the press-fitting. And it is sufficient.

  FIG. 18 is a diagram (after press-fitting) illustrating the state of lubricant application in the joint structure between the shaft portion and the bearing portion according to the second embodiment.

  In the present embodiment, the lubricant 32 supplied from the groove 28 a to the initial contact portion 34 is pushed down toward the back side of the hole 20 and lubricated from the groove 28 b to the initial contact portion 34 before depletion from the initial contact portion 34. Agent 35 is supplied. Thereby, the lubricant 35 is applied to at least the contact surface 23 on the back side from the groove 28b, and the lubricants 32 and 35 are applied to the contact surface 23 over the entire direction along the central axes 1a and 2a. Is realized.

  In the present embodiment, the grooves 28a and 28b are spaced apart in the direction along the central axis 19a of the shaft 19, so that the amount of the lubricants 32 and 35 held in the grooves 28a and 28b can be reduced. Can be reduced. As a result, the protrusion of the lubricants 32 and 35 when the grooves 28a and 28b are inserted (press-fitted) into the holes 20 can be reduced.

  In particular, the lubricants 32 and 35 that protrude from the groove 28 toward the front end surface 19 c of the shaft 19 accumulate between the front end surface 19 c and the bottom surface 20 c of the hole 20, and the front end surface 19 c of the shaft 19 contacts the bottom surface 20 c of the hole 20. This is a factor that obstructs the insertion (press-fit) of the shaft 19 into the bearing member 21 until it comes into contact. Therefore, in the joint structure between the shaft 19 and the bearing member 21 as in this embodiment, the protrusion of the lubricants 32 and 35 can be reduced, and a good joint structure can be realized.

  Further, in this embodiment, the grooves 28a and 28b are formed on the bearing member 21 side. For example, when the shaft 19 has a small diameter and the grooves 28a and 28b are formed, the shaft strength cannot be maintained. It is.

  In this embodiment, the groove 28 is formed on the bearing member 21 side, so that the amount of the lubricant 32 protruding from the groove 28a on the opening 24 side to the opening 24 side when the shaft 19 is press-fitted can be reduced. .

  The present embodiment includes a shaft 37 and a bearing member 39 that forms a hole 38 for press-fitting the shaft 37. A shaft side groove 42b is formed on the contact surface 41 with the bearing member 39 on the outer peripheral surface 37b of the shaft 37, and a contact surface 41 with the outer peripheral surface 37b of the shaft 37 is formed on the inner peripheral surface 38b of the hole 38 of the bearing member 39. The bearing side groove 42a is formed in the shaft. The shaft side groove 42b disposed in the direction 46 farther from the opening 45 of the hole 38 than the bearing side groove 42a is formed to have a width W and / or a depth D larger than that of the bearing side groove 42a.

  FIG. 19 is an external perspective view (when unfolded) showing the joint structure between the shaft portion and the bearing portion according to the third embodiment.

  The shaft (shaft portion) 37 has a cylindrical or columnar shape and is made of a martensitic stainless steel material. The shaft 37 is attached to, for example, a relief valve that is a part used in a high-pressure fuel pump, and is used as a stopper for fixing a spring. The bearing member (bearing portion) 39 has a cylindrical shape and is made of an austenitic stainless steel material. The bearing member 39 includes a hole (hole) 38 for press-fitting the shaft 37, and an inner wall (inner peripheral surface) 38 b of the hole 38 constitutes a bearing surface. The hole 38 is formed in the insertion direction of the shaft 37 (in the direction of the central axis 37 a of the shaft 37) 46 from the end surface 39 a of the bearing member 39. The shaft side groove 42 b is formed on the outer peripheral surface 37 b of the shaft 37. Further, the bearing side groove 42 a is formed in the inner peripheral surface 38 b of the hole 38. The shape and the like of the groove 42 (42a, 42b) will be described in detail later. The opening 45 is formed in the end surface 39 a of the bearing member 39 as an opening surface of the hole 38, and serves as an inlet for inserting the shaft 37 into the hole 38.

  FIG. 20 is an external perspective view (after assembly) showing a joint structure between the shaft portion and the bearing portion according to the third embodiment.

  The contact surface (contact portion or contact region) 41 is a region where the inner peripheral surface 38 b of the hole 38 contacts the outer peripheral surface 37 b of the shaft 37. The direction 46 is parallel to the central axis 37 a of the shaft 37 and the central axis 38 a of the hole 38, and is parallel to the insertion direction of the shaft 37. The direction 46 is a direction away from the opening 45 and along the contact surface 41 (a direction parallel to the contact surface 41). The shaft 37 is inserted into the hole 20 from the opening 45 along the direction 46.

  FIG. 21 is a cross-sectional view (when unfolded) illustrating the joint structure between the shaft portion and the bearing portion according to the third embodiment. FIG. 22 is a cross-sectional view (during assembly) illustrating a joint structure between a shaft portion and a bearing portion according to the third embodiment. FIG. 23 is a cross-sectional view (after assembling) illustrating the joint structure between the shaft portion and the bearing portion according to the third embodiment.

  In this embodiment, the hole 38 is formed in a bottomed cylindrical shape, and the innermost part of the hole 38 (inner wall 38b) is closed by a bottom (bottom surface) 38c. A chamfered portion 38 d is formed in the opening 45 of the hole 38. The present embodiment relates to the joint structure between the shaft 37 and the bearing member 39, and the contact area between the outer peripheral surface 37b of the shaft 37 and the inner wall 38b of the hole 38 is important. A description will be given with the opening 45 as the starting end of the inner wall 38b where the contact with the inner wall 38b begins. That is, the opening 45 is located on the back side of the hole 38 with respect to the chamfered portion 38d.

  A chamfered portion 37d is formed at the end of the shaft 37 on the distal end side in the insertion direction at the corner where the distal end surface 37c and the outer peripheral surface 37b intersect. In addition, about the dimension of the length direction of the axis | shaft 37, it is not necessarily restricted to the illustrated length, Various length can be taken.

  In this embodiment, as shown in FIG. 23, after the shaft 37 is assembled to the bearing member 39, the tip surface 37 c of the shaft 37 is in contact with the bottom surface 38 c of the hole 38. The joint structure of the shaft 37 and the bearing member 39 in the present embodiment can also be adopted in a configuration in which the tip surface 37c of the shaft 37 does not contact the bottom surface 38c of the hole 38.

  FIG. 24 is an enlarged view of the groove portion in the joint structure between the shaft portion and the bearing portion according to the third embodiment.

  In the present embodiment, the shaft side groove 42 b is formed on the outer peripheral surface 37 b of the shaft 37. The bearing side groove 42 a is formed on the inner peripheral surface 38 b of the hole 38. The shaft side groove 42 b is formed near the tip of the shaft 37, and the bearing side groove 42 a is formed near the opening 45 of the hole 38. As a result, in a state where the shaft 37 is assembled to the bearing member 39, the shaft-side groove 42b is located on the back side of the hole 38 with respect to the bearing-side groove 42a, and the bearing-side groove 42a is an opening 45 of the hole 38 with respect to the shaft-side groove 42b. Located on the side.

  In the present embodiment, the cross-sectional shape perpendicular to the longitudinal direction (extending direction) of the shaft side groove 42b and the bearing side groove 42a is a triangular shape. The width W and the depth D of the shaft side groove 42b are defined as shown in FIG. The width and depth of the bearing side groove 42a are also defined in the same manner as the width W and depth D of the shaft side groove 42b. The width W and depth D of the shaft side groove 42b and the bearing side groove 42a will be described later.

  The cross-sectional shape of the groove is not limited to a triangular shape, but may be a semicircle, a semi-ellipse, a part of a circle connected to a taper, a rectangle, a triangle, or other shapes.

  FIG. 25 is a diagram for explaining the state of lubricant application in the joint structure between the shaft portion and the bearing portion according to the third embodiment (the shaft portion 37 is inserted into the hole 38 of the bearing portion, and the shaft-side groove 42 passes through the bearing-side groove 44. FIG. In FIG. 25, the amounts (distribution) of the lubricants 49 and 50 on the contact surface 41 are schematically shown.

  When the tip 37c of the shaft 37 is inserted into the hole 38 and moves, the lubricant 50 held in the groove 42a and the lubricant 49 held in the groove 42b spread on the contact surface 41. As the shaft 37 is displaced relative to the bearing member 39 (the inner peripheral surface 38b of the hole 38) and is inserted (press-fitted) toward the inner side of the hole 38, the lubricants 49 and 50 are moved in the direction 46. Along the inner side of the hole 38, it is pushed down.

  In the case of only the shaft side groove 42 b, the lubricant 49 supplied from the shaft side groove 42 b is pushed down to the back side of the hole 38 with the movement of the shaft 37 on the opening 45 side from the central portion 51 in the direction 46 of the contact surface 41. As a result, the amount of the lubricant 49 becomes insufficient. Therefore, a bearing-side groove 42a is provided in the vicinity of the opening 45 of the inner peripheral surface 38b of the hole 38, and the lubricant 50 extends from the central portion 51 in the direction 46 of the contact surface 41 to the opening 45 side until press-fitting from the bearing-side groove 42a is completed. Supply. Thereby, the seizure between the shaft 37 and the hole 38 can be prevented.

  The width W of the bearing side groove 42a and the shaft side groove 42b is set to such an extent that the surface pressure does not decrease, and the depth D of the shaft side groove 42b is set to such an extent that the strength required for the shaft does not decrease. Further, the relationship between the width W and the depth D in the shaft side groove 42b is set so that the lubricant 49 does not protrude.

  Note that the lubricant 49 and the lubricant 50 may be made of the same material or different materials.

  FIG. 26 is a diagram for explaining the state of lubricant application in the joint structure between the shaft portion and the bearing portion according to the third embodiment (the shaft side groove 42 in the shaft portion 37 and the bearing side groove 44 in the hole 38 are It is a figure which shows that the lubricants 50 and 51 are supplied to the contact part 52). In FIG. 26, the amounts (distribution) of the lubricants 49 and 50 on the contact surface 41 are schematically shown.

  In the present embodiment, the width W and the depth D of the bearing side groove 42a are made smaller than the width W and the depth D of the shaft side groove 42b. Alternatively, either the width W or the depth D of the bearing side groove 42a is made smaller than the shaft side groove 42b. That is, the volume (cross-sectional area) of the bearing-side groove 42a is made smaller than the volume (cross-sectional area) of the shaft-side groove 42b. Accordingly, the amount of the lubricant 50 that can be held by the bearing side groove 42a is smaller than the amount of the lubricant 49 that can be held by the shaft side groove 42b. The width W and the depth D of the bearing-side groove 42a may be set so that the center contact portion 51 between the shaft-side groove 42b and the shaft-side groove 42a can hold the lubricant 50 to the extent that seizure does not occur until the press-fit is completed. .

  On the other hand, the shaft-side groove 42 b can hold a larger amount of the lubricant 49 than the bearing-side groove 42 a, and can supply the lubricant 49 to the back side of the hole 38.

  FIG. 27 is a diagram (after press-fitting) illustrating a lubricant application state in the joint structure between the shaft portion and the bearing portion according to the third embodiment.

  In the present embodiment, the lubricant 49 supplied from the central portion 51 of the contact surface 41 to the opening 45 side by the shaft side groove 42b is pushed down toward the back side of the hole 38 and is not depleted. 50 is supplied. As a result, the lubricant 50 is applied at least from the bearing-side groove 42a to the contact surface 41 on the opening 45 side from the central portion 51, and the lubricant 49 is applied to the contact surface 41 in the entire direction along the central axes 1a and 2a. , 50 is applied.

  Further, in the present embodiment, the bearing side groove 42a and the shaft side groove 42b are spaced apart in the direction along the central axis 37a of the shaft 37, so that the lubricants 50, 49 held in the grooves 42a, 42b can be obtained. The amount can be reduced. As a result, the protrusion of the lubricants 49 and 50 when the grooves 42a and 42b are inserted (press-fitted) into the holes 38 can be reduced.

  In particular, the lubricants 49 and 50 that protrude from the groove 42 toward the front end surface 37 c of the shaft 37 accumulate between the front end surface 37 c and the bottom surface 38 c of the hole 38, and the front end surface 37 c of the shaft 37 contacts the bottom surface 38 c of the hole 38. This is a factor that obstructs the insertion (press-fit) of the shaft 37 into the bearing member 39 until it comes into contact. Therefore, in the joint structure between the shaft 37 and the bearing member 39 as in this embodiment, the protrusion of the lubricants 49 and 50 can be reduced, and a good joint structure can be realized.

  In the present embodiment, the shaft-side groove 42b is formed on the shaft 37 side, and the bearing-side groove 42a is formed on the bearing member 39 side, whereby the two grooves 42a and 42b are divided into two members. This embodiment is advantageous when the press-fit length is short and it is difficult to form the two grooves 42a and 42b in either the shaft 37 or the bearing member 39.

  In the present embodiment, the amount of the lubricant 50 held by the bearing side groove 42a is made smaller than the amount of the lubricant 50 held by the shaft side groove 42b. For this reason, it is advantageous when it is desired to reduce the amount of lubricant protruding to the back side (tip surface 37 c side) of the hole 38 rather than the amount of lubricant protruding from the opening 45.

  The present embodiment includes a shaft 53 and a bearing member 55 that forms a hole 54 for press-fitting the shaft 53. A shaft-side groove 58b is formed in the contact surface 57 with the bearing member 55 on the outer peripheral surface 53b of the shaft 53, and the inner peripheral surface 54b of the hole 54 in the bearing member 55 is formed on the contact surface 57 with the outer peripheral surface 53b of the shaft 53. A bearing side groove 58a is formed. The shaft-side groove 58b disposed in the direction 62 away from the opening 61 of the hole 54 than the bearing-side groove 58a is formed so that the width W and / or the depth D is smaller than the bearing-side groove 58a.

  FIG. 28 is an external perspective view (when unfolded) showing the joint structure between the shaft portion and the bearing portion according to the fourth embodiment.

  The shaft (shaft portion) 53 has a cylindrical or columnar shape and is made of a martensitic stainless steel material. The shaft 53 is attached to, for example, a relief valve that is a part used in a high-pressure fuel pump, and is used as a stopper for fixing a spring. The bearing member (bearing portion) 55 has a cylindrical shape and is made of an austenitic stainless steel material. The bearing member 55 includes a hole (hole) 54 for press-fitting the shaft 53, and an inner wall (inner peripheral surface) 54 b of the hole 54 constitutes a bearing surface. The hole 54 is formed from the end surface 55 a of the bearing member 55 in the insertion direction of the shaft 53 (in the direction of the central axis 53 a of the shaft 53) 62. The shaft side groove 58 b is formed on the outer peripheral surface 53 b of the shaft 53. Further, the bearing side groove 58 a is formed in the inner peripheral surface 54 b of the hole 54. The shape and the like of the groove 58 (58a, 58b) will be described in detail later. The opening 61 is formed in the end surface 55 a of the bearing member 55 as an opening surface of the hole 54, and serves as an inlet for inserting the shaft 53 into the hole 54.

  FIG. 29 is an external perspective view (after assembly) showing a joint structure between a shaft portion and a bearing portion according to the fourth embodiment.

  The contact surface (contact portion or contact region) 57 is a region where the inner peripheral surface 54 b of the hole 54 and the outer peripheral surface 53 b of the shaft 53 are in contact with each other. The direction 62 is parallel to the central axis 53 a of the shaft 53 and the central axis 54 a of the hole 54, and is parallel to the insertion direction of the shaft 53. The direction 62 is a direction away from the opening 61 and along the contact surface 57 (a direction parallel to the contact surface 57). The shaft 53 is inserted into the hole 54 from the opening 61 along the direction 62.

  FIG. 30 is a cross-sectional view (when unfolded) illustrating the joint structure between the shaft portion and the bearing portion according to the fourth embodiment. FIG. 31 is a cross-sectional view (in the middle of assembly) illustrating the joint structure between the shaft portion and the bearing portion according to the fourth embodiment. FIG. 32 is a cross-sectional view (after assembly) showing the joint structure between the shaft portion and the bearing portion according to the fourth embodiment.

  In this embodiment, the hole 54 is formed in a bottomed cylindrical shape, and the innermost part of the hole 54 (inner wall 54b) is closed by a bottom part (bottom face) 54c. A chamfered portion 54 d is formed in the opening 61 of the hole 54. The present embodiment relates to the joint structure between the shaft 53 and the bearing member 55, and the contact area between the outer peripheral surface 53b of the shaft 53 and the inner wall 54b of the hole 54 is important. A description will be given with the opening 61 being the starting end of the inner wall 54b where the contact with the inner wall 54b begins. That is, the opening 61 is located on the back side of the hole 54 with respect to the chamfered portion 54d.

  A chamfered portion 53d is formed at the end of the shaft 53 on the distal end side in the insertion direction at a corner where the distal end surface 53c and the outer peripheral surface 53b intersect. In addition, about the dimension of the length direction of the axis | shaft 53, it is not necessarily restricted to the length shown in figure, Various length can be taken.

  In this embodiment, as shown in FIG. 32, after the shaft 53 is assembled to the bearing member 55, the tip surface 53 c of the shaft 53 is in contact with the bottom surface 54 c of the hole 54. The joint structure between the shaft 53 and the bearing member 55 in this embodiment can be employed even in a configuration in which the tip surface 53 c of the shaft 53 does not contact the bottom surface 54 c of the hole 54.

  FIG. 33 is an enlarged view of the groove portion in the joint structure between the shaft portion and the bearing portion according to the fourth embodiment.

  In the present embodiment, the shaft-side groove 58 b is formed on the outer peripheral surface 53 c of the shaft 53. The bearing side groove 58 a is formed on the inner peripheral surface 54 b of the hole 54. The shaft side groove 58 b is formed in the vicinity of the tip of the shaft 53, and the bearing side groove 58 a is formed in the vicinity of the opening 61 of the hole 54. As a result, in a state where the shaft 53 is assembled to the bearing member 55, the shaft-side groove 58b is located on the back side of the hole 54 with respect to the bearing-side groove 58a, and the bearing-side groove 58a is an opening 61 of the hole 54 with respect to the shaft-side groove 58b. Located on the side.

  In this embodiment, the cross-sectional shape perpendicular to the longitudinal direction (extending direction) of the shaft side groove 58b and the bearing side groove 58a is a triangle. The width W and the depth D of the bearing side groove 42a are defined as shown in FIG. The width and depth of the shaft side groove 58b are also defined in the same manner as the width W and depth D of the bearing side groove 42a. The width W and depth D of the shaft side groove 58b and the bearing side groove 58a will be described later.

  The cross-sectional shape of the groove may be a semicircle, a semi-ellipse, a part of a circle connected to a taper, a rectangle, a triangle, or other shapes.

  FIG. 34 is a diagram for explaining a lubricant application state in the joint structure between the shaft portion and the bearing portion according to the fourth embodiment (the shaft portion 53 is inserted into the hole 54 of the bearing portion, and the shaft-side groove 58 passes through the bearing-side groove 60. FIG. In FIG. 34, the amounts (distribution) of the lubricants 65 and 66 on the contact surface 57 are schematically shown.

  When the tip 53c of the shaft 53 is inserted and moved inside the hole 54, the lubricant 66 held in the groove 58a and the lubricant 65 held in the groove 58b spread on the contact surface 57. When the shaft 53 is displaced relative to the bearing member 55 (the inner peripheral surface 54 b of the hole 54) and is inserted (press-fitted) toward the inner side of the hole 54, the lubricants 65 and 66 are moved in the direction 46. Along the inner side of the hole 54, it is pushed down.

  In the case of only the shaft-side groove 58 b, the lubricant 65 supplied from the shaft-side groove 58 b is pushed down to the back side of the hole 54 with the movement of the shaft 53 on the opening 61 side from the central portion 67 in the direction 62 of the contact surface 57. As a result, the amount of the lubricant 65 becomes insufficient. Therefore, a bearing-side groove 58a is provided in the vicinity of the opening 61 of the inner peripheral surface 54b of the hole 54, and the lubricant 66 is provided from the center portion 67 in the direction 62 of the contact surface 57 to the opening 61 side until press-fitting from the bearing-side groove 58a is completed. Supply. Thereby, the seizure between the shaft 53 and the hole 54 can be prevented.

  The width W of the bearing side groove 58a and the shaft side groove 58b is set to such an extent that the surface pressure does not decrease, and the depth D of the shaft side groove 42b is set to such an extent that the strength required for the shaft does not decrease. Further, the relationship between the width W and the depth D in the bearing side groove 58a is set so that the lubricant 66 does not protrude.

  Note that the lubricant 65 and the lubricant 66 may be the same material lubricant or different material lubricants.

  FIG. 35 is a diagram for explaining the state of lubricant application in the joint structure between the shaft portion and the bearing portion according to the fourth embodiment (the shaft side groove 58 in the shaft portion 53 and the bearing side groove 60 in the hole 54 are It is a figure which shows that the lubricants 50 and 51 are supplied to the contact part 62). In FIG. 26, the amounts (distribution) of the lubricants 65 and 66 on the contact surface 57 are schematically shown.

  In the present embodiment, the width W and the depth D of the shaft side groove 58b are made smaller than the width W and the depth D of the bearing side groove 58a. Alternatively, either the width W or the depth D of the shaft side groove 58b is made smaller than the bearing side groove 58a. That is, the volume (cross-sectional area) of the shaft-side groove 58b is made smaller than the volume (cross-sectional area) of the bearing-side groove 58a. Thereby, the amount of the lubricant 65 that can be held by the shaft side groove 58b is smaller than the amount of the lubricant 66 that can be held by the bearing side groove 58a. The width W and the depth D of the bearing-side groove 58a may be set so that the center contact portion 67 between the shaft-side groove 58b and the bearing-side groove 58a can maintain the lubricant 66 that does not cause seizure until the press-fitting is completed. .

  The bearing side groove 58a can hold a larger amount of the lubricant 49 than the shaft side groove 58b, and the lubricant 66 can be stably supplied even when the length of the center contact portion 67 is large.

  FIG. 36 is a diagram (after press-fitting) illustrating a lubricant application state in the joint structure between the shaft portion and the bearing portion according to the third embodiment.

  In the present embodiment, the lubricant 65 supplied from the central portion 67 of the contact surface 57 to the opening 61 side by the shaft side groove 58b is pushed down toward the back side of the hole 54 and is not depleted from the bearing side groove 58a. 66 is supplied. Thereby, the lubricant 66 is applied at least from the bearing-side groove 58a to the contact surface 57 on the opening 61 side from the central portion 67, and the lubricant 65 is applied to the contact surface 67 in the whole direction along the central axes 53a and 54a. , 66 is applied.

  In the present embodiment, the bearing-side groove 58a and the shaft-side groove 58b are spaced apart in the direction along the central axis 53a of the shaft 53, so that the lubricants 65, 66 held in the grooves 58a, 58b are retained. The amount can be reduced. As a result, the protrusion of the lubricants 65 and 66 when the grooves 58a and 58b are inserted (press-fitted) into the holes 53 can be reduced.

  In particular, the lubricants 65 and 66 that protrude from the groove 58 toward the front end surface 53 c of the shaft 53 accumulate between the front end surface 53 c and the bottom surface 54 c of the hole 54, and the front end surface 53 c of the shaft 53 contacts the bottom surface 54 c of the hole 54. This is a factor that obstructs the insertion (press-fit) of the shaft 53 into the bearing member 55 until it comes into contact. Therefore, in the joint structure between the shaft 53 and the bearing member 55 as in this embodiment, the protrusion of the lubricants 65 and 66 can be reduced, and a good joint structure can be realized.

  In the present embodiment, the shaft-side groove 58b is formed on the shaft 53 side, and the bearing-side groove 58a is formed on the bearing member 55 side, so that the two grooves 58a and 58b are divided into two members. This embodiment is advantageous when the press-fit length is short and it is difficult to form the two grooves 58a and 58b in either the shaft 53 or the bearing member 55.

  In the present embodiment, the amount of the lubricant 50 held by the shaft side groove 58b is smaller than the amount of the lubricant 50 held by the bearing side groove 58a. For this reason, it is advantageous when the amount of lubricant protruding from the opening 61 is desired to be smaller than the amount of lubricant protruding to the back side of the hole 54 (on the front end surface 53c side).

Examples 1 to 4 have the following configuration.
Shafts 1, 29, 37, 53 and bearing members 3, 21, 39, 55 having holes 2, 20, 38, 54; In the joint structure with the bearing member,
In a state where the shaft is press-fitted into at least one of the outer peripheral surfaces 1b, 29b, 37b, 53b of the shaft and the inner peripheral surfaces 2b, 20b, 38b, 54b of the hole, the press-fitting directions 7, 25, 46 of the shaft The first grooves 10a, 28a, 42a, 58a provided on the side of the inlet openings 6, 24, 45, 61 for press-fitting the shafts of the holes, and the first grooves A second groove 10b, 28b, 42b, 58b provided on the side away from the inlet opening,
The area of the cross section perpendicular to the extending direction of the first groove and the area of the cross section perpendicular to the extending direction of the second groove are set to different sizes.

  As a result, an appropriate amount of lubricant can be held in the first groove and the second groove, the protrusion of the lubricant can be suppressed, and the lubricant can be supplied deep into the bearing portion (hole). .

  In addition, this invention is not limited to each above-mentioned Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

  DESCRIPTION OF SYMBOLS 1 ... Shaft, 1b ... Outer peripheral surface, 1c ... Front end surface of shaft 1, 1e ... Base end of shaft 1, 2 ... Hole, 2b ... Inner wall of hole 2, 3 ... Bearing member, 5 ... Shaft 1 and bearing member 3 6 ... opening, 7 ... direction away from opening 6, 10a, 10b ... groove, 13 ... initial contact portion, 15 ... lubricant, 18 ... lubricant, 19 ... shaft, 19b ... outer wall, 19c ... shaft 19 20 ... hole 20b ... inner peripheral surface of hole 20, 20c ... bottom surface of hole 20, 21 ... bearing member, 23 ... contact surface between shaft 19 and bearing member 21, 24 ... opening, 25 ... opening 24 28a, 28b ... groove, 32 ... lubricant, 34 ... initial contact part, 35 ... lubricant, 37 ... shaft, 37b ... outer peripheral surface of shaft 37, 38 ... hole, 38b ... inner peripheral surface of hole 38 39 ... Bearing member, 41 ... Contact surface between shaft 37 and bearing member 39, 42a ... Bearing side groove, 42b ... Shaft side groove, 45 ... Mouth, 46 ... direction away from opening 45, 49 ... lubricant, 50 ... lubricant, 51 ... central portion of contact surface, 53 ... shaft, 53b ... outer peripheral surface of shaft 53, 54 ... hole, 54b ... inner periphery of hole 54 55, bearing member, 57 ... contact surface between shaft 53 and bearing member 55, 58a ... bearing side groove, 58b ... shaft side groove, 61 ... opening, 62 ... direction away from opening 61, 65 ... lubricant, 66 ... lubrication Agent, 67 ... central part of contact surface.

Claims (5)

In a joint structure of a shaft and a bearing member, which includes a shaft and a bearing member having a hole, and joins the shaft and the bearing member by press-fitting the shaft into the hole.
The shaft is disposed on at least one of the outer peripheral surface of the shaft and the inner peripheral surface of the hole at a position spaced in the press-fitting direction of the shaft when the shaft is press-fitted into the hole. A first groove provided on the side of the inlet opening for press-fitting, and a second groove provided on the side away from the inlet opening with respect to the first groove,
A shaft and a bearing member characterized in that an area of a cross section perpendicular to the extending direction of the first groove and an area of a cross section perpendicular to the extending direction of the second groove have different sizes. Bonding structure. In the joint structure of the shaft and the bearing member according to claim 1,
The first groove and the second groove are provided on the outer peripheral surface of the shaft,
The joint structure of the shaft and the bearing member, wherein the area of the second groove is larger than the area of the first groove. In the joint structure of the shaft and the bearing member according to claim 1,
The first groove and the second groove are provided on an inner peripheral surface of the hole,
The joint structure of the shaft and the bearing member, wherein the area of the first groove is larger than the area of the second groove. In the joint structure of the shaft and the bearing member according to claim 1,
The first groove is provided on an inner peripheral surface of the hole;
The second groove is provided on the outer peripheral surface of the shaft,
The joint structure of the shaft and the bearing member, wherein the area of the second groove is larger than the area of the first groove. In the joint structure of the shaft and the bearing member according to claim 1,
The first groove is provided on an inner peripheral surface of the hole;
The second groove is provided on the outer peripheral surface of the shaft,
The joint structure of the shaft and the bearing member, wherein the area of the first groove is larger than the area of the second groove.

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