JPS6327576B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention consists of a synthetic resin outer ring divided into two transversely, an elastic inner ring having a lip seal portion on the inner diameter surface, and a synthetic resin intermediate ring divided into two transversely. This relates to a synthetic resin bearing with a flat surface. In particular, it is suitable as a bearing for supporting the steering shaft of an automobile, where there is concern about the intrusion of muddy water and dust, and where the bearing is subject to vibration. Conventionally, rolling bearings such as ball bearings, needle bearings, or cylindrical bearings have been used as bearings for this type of application. Intrusion, corrosion, and fretting corrosion may occur, impeding smooth operation. In order to solve these problems, the applicant first filed a patent application dated December 28, 1979.
No. 170520 discloses a bearing consisting of a synthetic resin inner ring and a synthetic resin outer ring, with sliding surfaces for the inner and outer rings, in which the inner ring is provided with an enlarged diameter at the portion where the inner hole of the inner ring opens on both end faces of the inner ring. The outer ring has an annular step and an annular groove provided in the inner hole surface, the outer ring has an annular lip that fits and slides into contact with the annular step of the inner ring, and side walls that slide into both end surfaces of the inner ring. The inner ring has a peripheral wall portion that slides in contact with the outer circumferential surface of the inner ring, and is fitted to hold the inner ring, and a rubber ring such as an O-ring is fitted into an annular groove provided in the inner hole surface of the inner ring. We proposed a synthetic resin bearing. In the above conventional technology, by fitting an O-ring to the inner hole surface of the inner ring, even if there is slight dimensional variation in the diameter of the shaft inserted into the inner hole of the inner ring, this can be absorbed and accommodated. This has resulted in effective dustproofing and vibration absorbing properties in the area. However, there is a limit to the ability to absorb and adapt to dimensional variations in shaft diameter due to elastic deformation of the O-ring. In reality, there is considerable variation in shaft diameter dimensions. For example, if the variation in shaft diameter dimensions is large on the negative side, a large gap will be created between the shaft and the O-ring, resulting in poor dust-proofing and vibration-absorbing properties. In addition, if the dimensional variation in the shaft diameter is large on the positive side, the shaft cannot be inserted, and the O-ring cannot sufficiently absorb the dimensional variation. A new problem has emerged that it cannot be done. The technical problem of the present invention is to improve the dustproof and waterproof properties of the bearing as well as the smooth operation of the bearing, and also to provide a bearing that can accommodate slight variations in the design dimensions of the mating shaft and displacement due to loads, and has followability. Furthermore, the purpose is to prevent muddy water and dust from entering from the outside and vibration, and to obtain a silencing effect that completely shuts out noise from the engine room. The structure of the present invention, that is, the technical means for solving the above technical problem is as follows. Consisting of an elastic inner ring, a synthetic resin intermediate ring divided into two transversely, and a synthetic resin outer ring divided into two transversely, the inner ring integrally has a lip seal portion on its inner diameter surface,
The intermediate ring has an annular side wall portion with a narrowed inner diameter at its end, and the inner ring is clamped and fitted thereto, and the outer ring has an annular lip portion that slides into contact with the inner peripheral surface of the annular side wall portion of the intermediate ring;
It has a side wall part that slides on the end surface of the annular side wall part of the intermediate ring, and a peripheral wall part that slides on the outer circumferential surface of the intermediate ring to hold the intermediate ring, and is elastically mounted at an engaging part formed on the joint surface. It further consists of an elastic inner ring, a synthetic resin intermediate ring divided into two transverse parts, and a synthetic resin outer ring divided into two transverse parts, and the inner ring integrally has a lip seal part on its inner diameter surface. The outer diameter surface has an annular side wall portion narrowing in the axial direction at equal intervals in the circumferential direction and an inner peripheral wall portion, and the peripheral wall portion has concave grooves extending in the axial direction at equal intervals in the circumferential direction. The inner ring is clamped and fitted by engaging the inner ring protrusion in the groove, and the outer ring has an annular lip part that slides on the inner peripheral surface of the annular side wall of the intermediate ring, and an annular side wall of the intermediate ring. A synthetic resin bearing that has a side wall portion that slides on an end face and a peripheral wall portion that slides on the outer circumferential surface of an intermediate wheel, holds the intermediate wheel, and has an elastic device at an engaging portion formed on the joint surface thereof. It is. The lip seal portion of the elastic inner ring is formed on the inner diameter surface of the inner ring in the shape of a truncated cone tapering in the axial direction with the inner diameter surface as the base, and the lip seal portion is given a degree of freedom of deformation in the radial direction. It is being Further, the method of joining the synthetic resin outer ring, which is divided into two transversely, is carried out by elastic attachment at an engaging portion formed on the joint surface. That is, the engaging portion formed on the joint surface extends beyond the outer circumferential surface of the outer ring by extending over the notch holes formed in the joint surface at equal intervals in the circumferential direction along the axial direction of the joint surface. The notch hole and the engaging protrusion are alternately formed at equal intervals in the circumferential direction, and protrude beyond the joining surface and have an engaging stepped portion at the tip thereof. The engagement tongue fits into the notch hole, and the distal end of the engagement step engages with the engagement protrusion for elastic attachment. Here, the material constituting the inner ring having an integral lip seal portion on its inner diameter surface is an elastic synthetic resin material, such as a polyester-ether copolymer (trade name Hytrel manufactured by Dupont Co., Ltd. or Pelprene manufactured by Toyobo Co., Ltd.). ), polyurethane resin, or rubber elastic bodies such as synthetic rubber and natural rubber are used. In addition, the synthetic resin that makes up the outer ring and intermediate ring, which are combined to form the sliding surface, has wear resistance, impact resistance,
It is necessary to have excellent mechanical properties such as creep resistance, and it is especially desirable for the intermediate ring to have self-lubricating properties. For example, polyamide resin, polyester resin such as polybutylene terephthalate (PBT), high molecular weight Polyolefin resins such as polyethylene or polypropylene,
In addition, filler filled tetrafluoroethylene resin is used successfully, as well as polycarbonate resin,
Polyphenylene oxide resins, polyphenylene sulfide resins, etc. may also be used. The outer ring uses the same synthetic resin as that used for the intermediate ring, but it has a particularly good combination of friction characteristics with the synthetic resin used for the intermediate ring, and is relatively rigid. Preferably, it is a synthetic resin material. Examples of desirable combinations are shown in the table below.

【table】

[Table] By adopting the above-mentioned technical means, the following functions and effects can be achieved. A frusto-conical lip seal portion, which is formed integrally with the inner diameter surface of the inner ring made of an elastic body and tapers in the axial direction from the inner diameter surface as a base, is given a large degree of freedom of deformation in the radial direction. Therefore, even if there is a large dimensional variation in the diameter of the shaft inserted there, the variation will be absorbed and accommodated, resulting in even better dustproof properties in that part, and the ripple reel itself has flexibility. Therefore, it is possible to follow the displacement relative to the load well. In addition, the annular lip of the outer ring makes sliding contact with the inner peripheral surface of the annular side wall of the intermediate ring, creating a labyrinth effect and acting as a seal to protect the inside of the bearing and prevent dust from entering the sliding surface. to prevent Furthermore, since the outer ring and the intermediate ring, which are divided into two transversely, are of the same shape, the manufacturing and assembly operations thereof are facilitated. Examples considered to be the most preferable will be described below in order to more specifically explain the technical means of the present invention. FIG. 1 is a plan view showing an embodiment of the bearing of the present invention;
FIG. 2 is a sectional view taken along the line A--A in FIG. 1. 1 is an inner ring made of an elastic body, 2 is a synthetic resin outer ring divided into two parts transversely, 3 is an engaging portion for elastic attachment formed on the joint surface of the outer ring 2 at equal intervals in the circumferential direction, and 4 is an outer ring made of elastic material. It is a synthetic resin intermediate wheel that is divided into two parts transversely. 3 is a plan view showing the inside of the inner ring 1, and FIG. 4 is a sectional view taken along the line B--B in FIG. Reference numeral 5 denotes a thin lip seal portion formed integrally with the inner ring 1 on the inner diameter surface thereof. The lip seal portion 5 is formed into a truncated conical shape tapering in the axial direction with the inner diameter surface of the inner ring as its base, and the lip seal portion 5 is given a large degree of freedom of deformation in the radial direction. Reference numeral 6 denotes an annular groove formed on one side of the base of the lip seal portion 5. The groove 6 provides flexibility to the lip seal portion 5 itself and facilitates displacement of the lip seal portion 5 under load. It is something. Reference numeral 7 denotes protrusions formed on the outer circumferential surface of the inner ring 1 at equal intervals in the circumferential direction along the axial direction thereof. 8 are both end surfaces of the inner ring. FIG. 5 is a plan view showing the inside of the synthetic resin intermediate ring 4 divided into two transversely, and FIG. 6 is a sectional view taken along the line C--C in FIG. 9 is an annular side wall formed at one end of the intermediate ring 4 by narrowing the inner diameter of the intermediate ring 4; 10 is an inner circumferential wall; and 11 is in sliding contact with an outer ring circumferential wall, which will be described later, to form a sliding surface. This is the outer circumferential surface of the structure. Reference numeral 12 denotes grooves formed in the inner circumferential wall portion 10 of the intermediate ring 4 at equal intervals in the circumferential direction along the axial direction thereof. A protrusion 7 formed on the outer peripheral surface of the inner ring fits into the groove 12, and both end surfaces 8 of the inner ring 1 abut against the annular side wall 9 of the intermediate ring 4. 1
are combined by sandwiching the outer circumferential surface and both end surfaces 8 of the
The intermediate ring 4 rotates together with the inner ring 1. Fig. 7 is a plan view showing the inside of the synthetic resin outer ring 2 which is divided into two transversely before joining, and Fig. 8 is Fig. 7 D-D.
FIG. 13 is an annular lip portion formed on the inner hole side of the outer ring 2, 14 is a side wall portion, 15 is a peripheral wall portion, and 16 is a joint surface. Reference numeral 17 indicates notch holes formed in the joint surface 16 of the outer ring 2 at equal intervals in the circumferential direction along the axial direction thereof, and reference numeral 18 indicates the joint surface 16 extending over the notch holes 17.
This is an engaging projecting piece formed on the outer circumferential surface of the side. Reference numeral 19 denotes engagement tongue portions formed alternately with the notch holes 17 and the engagement protrusions 18 at equal intervals in the circumferential direction of the joint surface 16; It is formed to protrude more than the other end, and an engagement step 20 is formed at the tip thereof. Reference numeral 21 denotes notches formed on both sides of the engaging tongue portion 19, and the notches 21 facilitate elastic deformation of the tongue portion 19. The notch hole 17 and the engaging protrusion 18 are combined with the engaging tongue portion 19 and the engaging stepped portion 20 to form the outer ring 2.
The engaging portion 3 is formed on the joint surface 16 of the. That is, the engaging tongue portion 19 formed on one joint surface 16 of the outer ring 2 having the same shape is fitted into the notch hole 17 formed on the joint surface 16 of the other outer ring 2 to be combined, By engaging the distal end engagement stepped portion 20 of the tongue portion 19 with the engagement projection portion 18 of the notch hole 17, the engagement portion 3 is formed there. In the outer ring 2 thus formed, the annular lip portion 13 formed on the inner hole side is in sliding contact with the inner circumferential surface of the annular side wall portion 9 of the intermediate ring 4, and the side wall portion 14 is in sliding contact with the inner peripheral surface of the annular side wall portion 9 of the intermediate ring 4. The peripheral wall portion 15 is assembled so as to be in sliding contact with the end surface of the intermediate ring 9 and the peripheral wall portion 15 is in sliding contact with the outer peripheral surface of the intermediate ring 4 . The annular lip portion 13 of the outer ring 2 makes sliding contact with the inner peripheral surface of the annular side wall portion 9 of the intermediate ring 4, creating a labyrinth effect there and serving as a seal, protecting the inside of the bearing and preventing dust from sliding. Prevent it from entering the surface. As mentioned above, the synthetic resin bearings obtained in this way can be used in locations subject to dust intrusion and vibration, such as bearings that support steering shafts of automobiles, especially bearings that are installed in steering joint dust covers. Optimal. FIG. 9 is an exploded view of the steering shaft part of an automobile in which the bearing of the present invention is effectively used.
2 is a steering column tube; 23 is a steering shaft inserted and held in the tube;
A steering joint dust cover 24 is inserted through the steering shaft 23 and attached to the lower end of the steering column tube 22. FIG. 10 is an enlarged perspective view of the cover 24.
is an insertion hole of the shaft 23, and 26 is an annular groove into which the bearing of the present invention is mounted. One engagement protrusion 18 provided on the outer ring of the bearing of the present invention and another engagement protrusion 1 opposing each other in the radial direction
8 is larger than the diameter of the annular groove 26 provided in the insertion hole 24, and when the bearing is installed in the groove 26, the diameter of the groove 26 is larger than the diameter of the annular groove 26 provided in the insertion hole 24. is enlarged by the engaging protrusions 18, 18, . This ensures that the bearing is installed securely.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an embodiment of the bearing of the present invention;
Figure 2 is a sectional view taken along the line A-A in Figure 1, Figure 3 is a plan view of the inner ring, Figure 4 is a sectional view taken along the line B-B in Figure 3, and Figure 5 is a plan view of the intermediate ring. Figure 6 shows C-C in Figure 5.
Line sectional view, Figure 7 is a plan view of the outer ring, Figure 8 is the 7th
FIG. 9 is an exploded view of the steering shaft portion of the automobile, and FIG. 10 is an enlarged perspective view of the steering joint dust cover. 1: Inner ring, 2: Synthetic resin outer ring, 3: Engagement part,
4: Synthetic resin intermediate ring, 5: Lip seal part.

Claims (1)

[Claims] 1. Consisting of an elastic inner ring, a synthetic resin intermediate ring divided into two transverse parts, and a synthetic resin outer ring divided into two transverse parts,
The inner ring integrally has a lip seal portion on its inner diameter surface, the intermediate ring has an annular side wall portion with a narrowed inner diameter at its end, and the inner ring is sandwiched and fitted therein. It has an annular lip portion that slides on the circumferential surface, a side wall portion that slides on the end surface of the annular side wall portion of the intermediate ring, and a peripheral wall portion that slides on the outer circumferential surface of the intermediate ring to hold the intermediate ring, and the joint surface thereof. A synthetic resin bearing characterized in that it is elastically attached at an engaging portion formed in the bearing. 2 Consists of an elastic inner ring, a synthetic resin intermediate ring divided into two transverse parts, and a synthetic resin outer ring divided into two transverse parts,
The inner ring integrally has a lip seal portion on its inner diameter surface, and has protrusions extending along its axial direction at equal intervals in the circumferential direction on its outer diameter surface, and the intermediate ring has an annular shape with a narrowed inner diameter at its end. It has a side wall portion and an inner circumferential wall portion, and the circumferential wall portion has concave grooves extending along the axial direction at equal intervals in the circumferential direction, and the inner ring protrusion portion is engaged with the concave grooves, and the inner ring protrusion portion is engaged with the grooves. The outer ring has an annular lip that slides into contact with the inner peripheral surface of the annular side wall of the intermediate ring, and
It has a side wall part that slides on the end surface of the annular side wall part of the intermediate ring, and a peripheral wall part that slides on the outer circumferential surface of the intermediate ring to hold the intermediate ring, and is elastically mounted at an engaging part formed on the joint surface. A synthetic resin bearing characterized by: 3. The lip seal portion of the elastic inner ring is formed on the inner diameter surface of the inner ring in the shape of a truncated cone tapering in the axial direction with the inner diameter surface as the base. Synthetic resin bearings as described in section. 4. The engaging part formed on the joint surface of the synthetic resin outer ring divided into two transversely has cut holes formed in the joint surface at equal intervals in the circumferential direction along the axial direction. Engagement protrusions are formed to straddle and protrude from the outer circumferential surface of the outer ring, and the notch holes and engagement protrusions are alternately formed at equal intervals in the circumferential direction, and protrude from the joint surface and are arranged at equal intervals in the circumferential direction. The engaging tongue part has an engaging stepped part at the tip, and the engaging tongue part fits into the notch hole, and the engaging tongue part at the leading end is engaged with the engaging protrusion part. A synthetic resin bearing according to any one of claims 1 to 3, characterized in that it is elastically mounted.