JPH05231456A - Sliding bush - Google Patents

Abstract

PURPOSE:To provide a sliding bush heightened in axial rigidity and strength while being reduced in circumferential sliding resistance. CONSTITUTION:This sliding bush is formed of a cylindrical outer cylinder fitting 2 having a ring-shaped first protruding part 20 with its inner diameter protruding radially inward; an inner cylinder fitting 4 having a ring-shaped recessed part 44 and a pair of ring-shaped second protruding parts 46 protruding radially outward; a sliding member 6 made of resin; and a lubricating layer 62 disposed between the sliding member 6 and inner cylinder fitting 4. The outer diameter of the second protruding part 46 is larger than the inner diameter of the first protruding part 20, and both are overlapped in the radial direction. The inner cylinder fitting 4 is formed of a first split body 41 inserted from one end 2e of the outer cylinder fitting 2 at the molding time, and a second split body 42 inserted from the other end 2f.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sliding bush in which an inner member is slidable in a circumferential direction and a twisting torque is reduced. This sliding bush can be used as, for example, a vehicle suspension bush.

[0002]

2. Description of the Related Art As a sliding bush, for example, a vehicle suspension bush, as shown in FIG.
And an inner tubular metal fitting 102 having a ring-shaped protruding portion 101 which is arranged substantially coaxially in the outer tubular metal fitting 100, and an inner tubular metal fitting 10
2 and the sliding member 103 arranged between the outer tubular metal fitting 100
It is known that it is composed of and. The sliding member 103 is made of a resin material. A minute clearance is formed in the boundary region between the sliding member 103 and the inner tubular metal member 102, whereby the sliding resistance of the inner tubular metal member 102 in the circumferential direction is reduced.

By the way, in order to manufacture the above-mentioned sliding bush, an outer cylindrical metal fitting 100 having an inner peripheral surface coated with an adhesive is used.
The inner tubular metal fitting 102 is arranged in the outer tubular metal fitting 100, and in that state, a resin is loaded into the space between the inner tubular metal fitting 102 and the outer tubular metal fitting 100 to form the sliding member 103, and then the ring shape is formed. The stopper metal fitting 105 is press-fitted into the outer cylindrical metal fitting 100 and locked to the shaft end of the sliding member 103.

Therefore, when a large load is applied in the axial direction, the stopper fitting 105 is deformed or comes off in the axial direction, causing rattling. Therefore, the sliding bush shown in FIG.
There was a limit to the improvement of axial rigidity and strength. Therefore, there is a problem that the sliding bush shown in FIG. 9 cannot be applied when an excessive load acts in the axial direction.

A sliding bush shown in FIG. 10 is also known. Similarly to the sliding bush shown in FIG. 9, this sliding bush is filled with resin between the inner tubular metal member 202 and the outer tubular metal member 200 to form the sliding member 203, and thereafter, the ring-shaped stopper metallic member 205. Is inserted into the outer tubular metal fitting 200, the shaft end of the outer tubular metal fitting 200 is caulked to form a caulked portion 210, and the sliding member 203 is locked by the stopper metal fitting 205 fixed by the caulking portion 210. Are known. In this case, although the caulking portion 210 improves the rigidity and strength in the axial direction, there is a limit to that and there is a problem that a caulking step is required.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and it is possible to increase the rigidity and strength in the axial direction while reducing the sliding resistance in the circumferential direction without caulking the outer metal fitting. It is to provide a sliding bush.

[0007]

A sliding bush according to the present invention comprises a tubular outer member having a ring-shaped first projecting portion having a predetermined inner diameter projecting radially inward in a central region in the axial direction, A ring-shaped recess that is arranged substantially coaxially inside the outer member and faces the first protruding portion, and an outer diameter larger than the inner diameter of the first protruding portion that is formed so as to project radially outward at both axial ends of the recess. An inner member having a pair of ring-shaped second protrusions having
And a sliding member made of a resin material and disposed between the inner member and the outer member to allow the inner member to rotate in its circumferential direction, the inner member being divided in series in the axial direction, and First split with two protrusions and second of the other
It is characterized in that it is composed of a second divided body having a protruding portion.

The outer diameter of the second protrusion of the inner member is set larger than the inner diameter of the first protrusion of the outer member. Therefore, the first protrusion and the second protrusion overlap in the radial direction. The overlap amount can be appropriately set according to the type of sliding bush. The resin that constitutes the sliding member may be a thermosetting resin or a thermoplastic resin, for example, a nylon resin, a phenol resin, or the like, and may include a reinforcing fiber such as glass fiber, carbon fiber, or aramid fiber.

Further, if a lubricating layer formed of fluorine fiber is integrally formed with the resin on the inside of the resin forming the sliding member, that is, the surface on which the sliding movement is performed, the sliding property can be further improved.

[0010]

In the sliding bush of the present invention, when an input is applied in the circumferential direction, the inner member slides relative to the sliding member, so the sliding resistance in the circumferential direction is small. On the other hand, when an axial load is applied, the first protrusion of the outer member and the second protrusion of the inner member overlap each other, so that the rigidity and strength in the axial direction are large.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the sliding bush of the present invention is shown in FIGS.
This will be described with reference to FIG. FIG. 1 shows a sectional view of the sliding bush 1, and FIG. 2 shows a usage state of the sliding bush 1. FIG. 3 shows a cross section of the outer tubular metal member 2 as an outer member. As shown in FIG. 3, a first projecting portion 20 projecting radially inward is formed in a ring shape in the central region of the outer tubular metal fitting 2 in the axial direction. The first protrusion 20 has a ring-shaped same-diameter surface 22 and a same-diameter surface 22.
And a ring-shaped first inclined surface 23 continuously provided at the axial end of the. Here, the inner diameter of the same diameter surface 22 of the first protruding portion 20 is indicated by D3, and the inner diameter of the same diameter surface 24 of the shaft end of the outer tubular fitting 2 is indicated by D1. Further, an injection hole 27 is formed in the middle portion of the outer tubular metal fitting 2.

FIG. 4 shows a cross section of the inner cylindrical metal member 4 as an inner member. The inner tubular member 4 is formed of a first divided body 41 and a second divided body 42 which are divided in the axial direction. The first divided body 41 is made of steel and has a cylindrical shape with a central hole 43. A concave portion 44 is formed on the outer peripheral surface of the first divided body 41.
A recessed portion forming surface 45 having the same diameter is formed to partition the. On the end side of the recess forming surface 45, a second protruding portion 46 that protrudes radially outward is formed in a ring shape. Second protrusion 46
Is formed of a second inclined surface 47 that is continuous with the recess forming surface 45 and a protruding surface 48 of the same diameter. Here, in FIG. 4, the outer diameter of the recess forming surface 45 of the inner tubular member 4 is indicated by D4, and the outer diameter of the protruding surface 48 of the second protruding portion 46 is indicated by D2. Here, the dimensional relationship is set to D1>D2>D3> D4. As can be understood from FIG. 4, the second divided body 42
Also has the same shape as the first divided body 41.

As shown in FIG. 1, the sliding member 6 is an outer cylinder fitting 2
It is arranged between the inner tubular metal member 4 and the outer tubular metal member 2 in a state of being adhered to. The sliding member 6 is made of nylon resin containing glass fibers and formed into a tubular shape. Sliding member 6 and inner tube fitting 4
A lubricating layer 62 made of a sliding cloth is interposed between and. The sliding cloth is usually made of a low friction material such as fluororesin-based polytetrafluoroethylene (PTFE).
Approximately 10000 denier yarn 20-inch
It is formed by weaving at a density of about 200, and preferably, resin impregnation can be adopted.

The sliding bush 1 of this embodiment is manufactured as follows. First, an adhesive is applied to the inner peripheral surface of the outer tubular fitting 2. In this state, the cylindrical body 63 in which the adhesive that is the rolling cloth that constitutes the lubricating layer 62 is applied is inserted into the outer cylindrical metal fitting 2 as shown in FIG. After that, as shown in FIG. 5, the first divided body 41 is inserted into the outer tubular metal fitting 2 from the end 2e side by the arrow X.
While being inserted in one direction, the second divided body 42 is inserted into the outer tubular metal fitting 2 from the other end 2f side in the arrow X2 direction, and the shaft end surfaces 52 of the first divided body 41 and the second divided body 42 are brought into contact with each other. Let
As a result, the cylindrical structure 65 having the ring-shaped space 64 shown in FIG. 5 is obtained. In this state, as shown in FIG.
The first projecting portion 20 and the second projecting portion 46 of the inner tubular member 4 overlap each other by (E × 2) in the radial direction. Here, (E × 2) = (D2-D3)> 0.

Further, as shown in FIG. 6, this tubular structure 65
Is placed in a predetermined portion of the cavity 68 of the injection mold 67. In this state, the runner 69 of the injection mold 67 and the injection hole 27 of the outer tubular fitting 2 communicate with each other. In this state, the resin containing glass fiber is loaded into the space 64 of the tubular structure 65 from the runner 69 of the injection molding die 67 through the injection hole 27 of the outer tubular fitting 2 at a predetermined injection molding pressure to solidify the resin. The sliding member 6 is formed, and thus the sliding bush 1 is formed. Then, the separation die 67a is removed, and the sliding bush 1 is taken out from the molding die 67. Here, as described above, since the adhesive is applied to the inner peripheral surface of the outer tubular metal fitting 2, the resin that becomes the sliding member 6 is bonded to the inner peripheral surface of the outer tubular metal fitting 2 in the thickness direction. Since it contracts, a minute clearance is formed between the sliding member 6 and the inner tubular member 4. Predetermined heat treatment (150 ° C x 10
60 minutes) may be performed.

After that, a ring-shaped dust seal 29 is inserted and attached to the shaft end side of the outer tubular member 2. In the completed sliding bush shown in FIG. 1, the first protruding portion 20 of the outer tubular metal fitting 2 faces the recess 44 of the inner tubular metal fitting 4. Further, as understood from the above description, the first projecting portion 20 of the outer tubular metal fitting 2 and the second projecting portion 46 of the inner tubular metal fitting 4 overlap in the radial direction. Therefore, the first inclined surface 23 of the first protruding portion 20.
The second inclined surface 47 of the second protruding portion 46 faces each other via the sliding member 6.

The sliding bush 1 of this embodiment can be used in the state shown in FIG. 1, but may be used in the following state. That is, the sliding bush 1 shown in FIG.
A cylindrical metal fitting having an inner diameter larger than the outer diameter of the outer tubular metal fitting 2 is used, and both are arranged substantially coaxially at a predetermined portion of the cavity of the vulcanization mold, and a rubber is provided between the outer tubular metal fitting 2 and the cylindrical metal fitting. It is also possible to load the material and vulcanize it, whereby a tubular rubber elastic body is formed between the outer tubular fitting 2 and the cylindrical fitting.

(Mode of Use) When using the sliding bush 1 described above, as shown in FIG. 2, the sliding bush 1 is inserted into the bush mounting hole A1 of one of the vehicle body and the arm A, and Also, the sliding bush 1 is arranged between the mounting portions B1 on the other side B of the arms, and further, the bolts C1 that have passed through the bolt insertion holes B2 of the mounting portions B1 are inserted into the central hole 43 of the inner tubular fitting 4. Screw with nut C2.

In this state, the first tubular member constituting the inner tubular metal member 4 is formed.
The shaft end faces 51 of the divided body 41 and the second divided body 42 are attached to the mounting portion B.
1 and is restricted in the axial direction by the mounting portion B1. (Effect) In the sliding bush 1 of this embodiment, when a rotational input in the circumferential direction is applied, the sliding member 6 or the lubricating layer 6
2. Since the inner tubular member 4 can slide in the circumferential direction through the minute clearance, the sliding resistance in the circumferential direction is small as in the conventional case. On the other hand, as described above, the first projecting portion 20 of the outer tubular metal fitting 2 and the second projecting portion 46 of the inner tubular metal fitting 4 are radially (E × 2).
Probably overlapping. Therefore, when a load is applied in the axial direction, the first inclined surface 2 of the first protruding portion 20 of the outer tubular fitting 1
Since 3 and the second inclined surface 47 of the second protruding portion 46 of the inner tubular member 4 can be displaced so as to be close to each other in the axial direction, rigidity and strength in the axial direction can be increased.

Further, in this embodiment, the outer diameter D2 of the second projecting portion 46 of the inner tubular metal fitting 4 is set to be larger than the inner diameter D3 of the first projecting portion 20 of the outer tubular metal fitting 2, and both of them are set in the radial direction. The overlapping structure is the characteristic structure. In such an overlap structure, if the inner tubular metal fitting 4 is of an integral type and the shaft end surface 52 of the first divided body 41 and the shaft end surface 52 of the second divided body 42 are integrally connected, the first protrusion is formed. Part 2
0 and the second protrusion 46 interfere with each other, and the inner tubular metal fitting 4 cannot be inserted into the outer tubular metal fitting 2. In this regard, in this embodiment, the first divided body 41 and the second divided body 42 are separate bodies, and therefore, FIG.
As shown in FIG. 2, the first divided body 41 can be inserted into the outer tubular metal fitting 2 from the one end 2e side in the arrow X1 direction, and the second divided body 4 can be inserted.
Since 2 can be inserted into the outer tubular metal member 2 from the other end 2f side in the arrow X2 direction, the above-mentioned overlap structure can be easily achieved.

(Other Embodiments) FIG. 7 shows a sliding bush 8 according to a second embodiment of the present invention. In this example, a tubular structure 66 including the inner tubular metal member 4, the sliding member 6, the lubricating layer 62, and the outer tubular metal member 2 and the cylindrical metal member 7 having an inner diameter larger than the outer diameter of the outer tubular metal member 2 are used. .. Then, the cylindrical structure 66 and the cylindrical metal fitting 7 are arranged substantially coaxially in a predetermined portion of a cavity of a vulcanization mold (not shown), and a rubber material is loaded between the outer cylindrical metal fitting 2 and the cylindrical metal fitting 7. Then, the rubber elastic body 70 which is vulcanized and has a substantially uniform thickness is formed between the outer cylindrical metal fitting 2 and the cylindrical metal fitting 7. The rubber elastic body 70 improves the vibration damping effect.

Further, as in the third embodiment shown in FIG. 8, the shaft end surface 52 and the second end surface 52 of the first divided body 41 constituting the inner tubular metal member 4 are arranged.
It is also possible to form a concave locking portion 53 and a convex locking portion 54 on the shaft end surface 52 of the split body 42 and fit them together. In this case, the first divided body 41 and the second divided body 42 are surely prevented from being displaced in the direction perpendicular to the axis, and the first divided body 41 and the second divided body 42 are prevented.
The unity of the divided body 42 is enhanced. In addition, the concave locking portion 5
3. When the convex locking portions 54 are formed on the shaft end surface 52 at phases of 180 degrees, the first divided body 41 and the second divided body 4 are formed.
Can be shared with 2.

[0023]

In the sliding bush according to the present invention, the inner member can be displaced in the circumferential direction when a load is applied in the circumferential direction, so that the sliding resistance in the circumferential direction is small as in the conventional case. On the other hand, since the outer diameter of the second protruding portion of the inner member is set to be larger than the inner diameter of the first protruding portion of the outer member, the first protruding portion of the outer member and the second protruding portion of the inner member are set as described above. And overlap in the radial direction. Therefore, when a load is applied in the axial direction, the first protrusion of the outer member and the second protrusion of the inner member can be displaced so as to be close to each other in the axial direction. Therefore, the rigidity and strength in the axial direction can be increased.

In the sliding bush according to the present invention, since the first divided body and the second divided body are separate from each other, the first divided body can be inserted into the outer member from one end side and the second divided body can be inserted.
Since the split body can be inserted into the outer member from the other end side, the above-described overlap structure can be easily achieved.

[Brief description of drawings]

FIG. 1 is a sectional view of a sliding bush of the present invention.

FIG. 2 is a sectional view showing a state where the sliding bush of the present invention is used.

FIG. 3 is a sectional view of an outer cylinder fitting of the sliding bush of the present invention.

FIG. 4 is a cross-sectional view of an inner tubular metal member of the sliding bush of the present invention.

FIG. 5 is a cross-sectional view of the sliding bush of the present invention with an inner tubular metal fitting inserted into an outer tubular metal fitting.

FIG. 6 is a cross-sectional view of a state in which a resin forming the sliding member of the sliding bush of the present invention is loaded.

FIG. 7 is a sectional view of a sliding bush according to a second embodiment of the present invention.

FIG. 8 is a sectional view of a sliding bush according to a third embodiment of the present invention.

FIG. 9 is a cross-sectional view of a conventional sliding bush.

FIG. 10 is a cross-sectional view of another conventional sliding bush.

[Explanation of symbols]

In the figure, 2 is an outer tubular metal fitting, 20 is a first protruding portion, 4 is an inner tubular metal fitting, 41 is a first divided body, 42 is a second divided body, 44 is a concave portion, 46 is a second protruding portion, and 6 is a slide. The moving member 67 is an injection mold.

Claims (1)

[Claims] 1. A tubular outer member having a ring-shaped first projecting portion having a predetermined inner diameter and projecting radially inward in a central region in the axial direction, and arranged substantially coaxially in the outer member. A ring-shaped recess facing the first protrusion, and a pair of ring-shaped recesses formed at both axial ends of the recess to project radially outward and having an outer diameter larger than the inner diameter of the first protrusion. 2 an inner member having two protrusions, and a sliding member made of a resin material and disposed between the inner member and the outer member to allow the inner member to rotate in its circumferential direction. A sliding bush characterized in that the member is divided in series in the axial direction and is composed of a first divided body having one second protruding portion and a second divided body having the other second protruding portion.