JP3399091B2 - Bearing device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The bearing device according to the present invention is used in a state of being incorporated in a strut for constituting a suspension device for supporting a front wheel of an automobile. 2. Description of the Related Art Among strut-type suspension devices for supporting the front wheels of an automobile, which are steering wheels, a strut-type suspension device includes:
A damper case constituting an oil damper is supported so as to be able to move up and down with respect to the vehicle body. The front wheel is rotatably supported by a pivot fixed to the lower end of the damper case, and the oil damper is rotatably supported by the vehicle body. Therefore, between the upper end of the rod constituting the oil damper and the vehicle body, a thrust bearing for rotatably supporting this rod while supporting a thrust load is required. In the case of an actual strut, an upper spring seat is fixed to an upper end of the rod, and a lower spring seat is fixed to an intermediate portion of the damper case. A compression spring is provided between the lower surface of the upper spring seat and the upper surface of the lower spring seat to apply downward elastic force to the oil damper. That is, the compression spring is provided between the wheel and the vehicle body, and the compression spring supports the weight of the vehicle body. The thrust bearing is provided between an upper surface of the upper spring seat and a lower surface of a mounting plate provided on the vehicle body. That is, the thrust bearing is provided around the upper end of the rod, and the thrust bearing supports a thrust load acting between the upper spring seat and the mounting plate. The thrust bearing may directly hit the lower surface of the mounting plate portion, or may hit it via a spacer called an upper support. Although the load acting between the upper spring seat and the mounting plate is almost a thrust load, the radial load also acts to a small extent. For this reason, conventionally, in addition to the thrust bearing, a radial bearing has generally been incorporated between the upper spring seat and the mounting plate portion. Conventionally, a bearing device capable of mainly supporting a thrust load and also supporting a relatively small radial load has been conventionally known, for example, from Japanese Utility Model Laid-Open Publication No. 59-24530 or U.S. Pat. No. 44667.
A bearing device described in the specification of Japanese Patent No. 51 is known. [0005] FIG. 9 shows a U.S. Pat.
51 shows a state in which the bearing device described in the specification of No. 51 is mounted on the upper surface of an upper spring seat 1 which is a mating member constituting a suspension device. This bearing device comprises a plurality of rolling elements 4 between an inner ring 2 which is a first race and an outer race 3 which is a second race, each of which is made of a hard metal such as bearing steel. Is held so that it can roll freely. The inner race 2 has an inner raceway 5 as a first raceway on a lower surface, and a first cylindrical portion 6 protruding above an inner peripheral edge (right edge in FIG. 9). Further, an inner bent portion 7 which is bent downward is formed on the outer peripheral edge portion (left edge portion in FIG. 9) of the inner ring 2. On the other hand, the outer race 3 has an outer raceway 8 as a second raceway on the upper surface. Further, an outer bent portion 9 which is bent upward is formed on an outer peripheral edge portion (left edge portion in FIG. 9) of the outer ring 3. When the bearing device is assembled, the outer bent portion 9 is located outside the inner bent portion 7 (left side in FIG. 9). In this state, the inner peripheral surface (the right side in FIG. 9) of the outer bent portion 9 and the inner bent portion 7
A small gap is interposed between the outer peripheral surface (the left surface in FIG. 9) and the outer peripheral surface (see FIG. 9). Therefore, the relative rotation between the inner ring 2 and the outer ring 3 is free. In addition, a seal ring 12 composed of a cored bar 10 and a sealing material 11 is fitted on the outer bent portion 9. With the suspension device assembled, this seal ring 12
The top edge (the upper edge in FIG. 9) of the sealing member 11 is provided on the mounting plate portion side such as the upper support, and is elastically pressed against the lower surface of a member that comes into contact with the upper surface of the inner ring 2. Then, it comes into sliding contact with the lower surface, and rainwater, muddy water, etc. (hereinafter simply referred to as “rainwater, etc.”) inside the seal ring 12.
To prevent entry. The plurality of rolling elements 4 are rotatably provided between the outer raceway 8 and the inner raceway 5 while being held by the retainer 13. When the thrust load to be supported is small, a ball may be used as the rolling element 4 instead of the illustrated roller. Further, a sleeve 14 made of a slippery synthetic resin such as polyamide resin (nylon), Duracon, polytetrafluoroethylene (PTFE), or the like is externally fitted to the first cylindrical portion 6. It is fixed. With the lower surface of the outer race 3 in contact with the upper surface of the upper spring seat 1 in order to assemble the bearing device with the suspension, the inner peripheral surface (the right surface in FIG.
The outer peripheral surface of the second cylindrical portion 15 formed on the inner peripheral edge of FIG.
On the left side of FIG. In the bearing device having such a structure, the thrust load applied according to the vehicle weight is supported by the plurality of rolling elements 4. A radial load caused by a force applied in a direction perpendicular to the axis of the strut, such as a stress caused by a centrifugal force generated at the time of turning, causes the inner peripheral surface of the sleeve 14 and the outer peripheral surface of the second cylindrical portion 15 to slide. Then, the upper spring seat 1 is supported. [0009] In the case of the conventional bearing device configured as described above, the effect of preventing rainwater or the like from entering the rolling element 4 installation portion is not always sufficient. That is, a radial minute gap 16 exists between the inner peripheral surface of the sleeve 14 and the outer peripheral surface of the second cylindrical portion 15 so that the rotation of the sleeve 14 is performed smoothly. Moreover, the upper end of the radial minute gap 16 is open upward. Therefore, when rainwater or the like is sprayed from above the upper spring sheet 1, the rainwater or the like may enter the radial minute gap 16, and may enter the rolling element 4 installation portion through the radial minute gap 16. As described above, when foreign matter such as mud contained in rainwater or the like that has entered the rolling element 4 installation portion enters the contact portion between the rolling surface of the rolling element 4 and the inner raceway 5 and the outer raceway 8, This not only increases the rotational resistance of the bearing device, but also damages these rolling surfaces and raceway surfaces. And it is not preferable because the durability of the bearing device is deteriorated. The bearing device of the present invention,
The present invention has been made in view of such circumstances, and provides a structure in which rainwater or the like hardly enters the rolling element 4 installation portion through the radial minute gap 16. [0011] The bearing device of the present invention has a first track on the lower surface, similar to the conventional bearing device described above.
An annular first orbital ring having a first cylindrical portion protruding upward at an inner peripheral edge thereof; an annular second orbital ring having a second orbital on an upper surface; and the first orbital A plurality of rolling elements rotatably provided between the first and second tracks, and a sleeve made of synthetic resin in a cylindrical shape and fixedly fitted in the first cylindrical portion. Then, the lower surface of the second race is brought into contact with the upper surface of the mating member constituting the suspension device, and the inner circumferential surface of the sleeve is formed on the outer circumferential surface of the second cylindrical portion formed on the inner circumferential edge of the mating member. Are supported on the upper surface of the counterpart member in a state where they face each other via the radial minute gap. In particular, in the bearing device of the present invention, a projecting portion projecting inward in the diameter direction is formed over the entire circumference at the upper end of the inner peripheral surface of the sleeve. Then, at the time of assembling on the upper surface of the counterpart member, the lower surface of the protruding portion and the upper edge of the second cylindrical portion oppose each other via the thrust minute gap. The operation of the bearing device of the present invention configured as described above when supporting a thrust load and a radial load is the same as that of the above-described conventional bearing device. In particular, in the case of the bearing device of the present invention, since the upper end of the radial minute gap is covered with the protruding portion, rainwater or the like splashed from above does not directly enter the radial minute gap. One end of the thrust minute gap is continuous with the upper end of the radial minute gap. However, since the other end of the thrust minute gap is opened inward in the diametrical direction, rainwater or the like hardly enters the thrust minute gap. As a result, it becomes difficult for this rainwater or the like to enter the rolling element installation portion. 1 and 2 show a first embodiment of the present invention. The feature of the present invention is that the shape of the sleeve mounted on the inner peripheral edge (right edge in FIGS. 1 and 2) of the inner race 2 as the first race is devised so that rainwater or the like Is difficult to enter. The configuration and operation of the other parts
This is the same as the conventional structure shown in FIG. Therefore, the same parts as those of the conventional structure are denoted by the same reference numerals, and the description thereof will not be repeated. First cylindrical portion 6 formed on the inner peripheral edge of inner ring 2
An eave-shaped projection 17 projecting inward in the diametric direction (to the right in FIGS. 1 and 2) is provided on the upper end of the inner peripheral surface (the right surface in FIGS. It is formed over. Then, at the time of assembling to the upper surface of the upper spring seat 1 which is a mating member, the second surface formed on the lower surface of the projecting portion 17 and the inner peripheral edge (the right edge in FIGS. The thrust minute gap 18 is connected to the upper edge of the cylindrical portion 15.
Are opposed to each other. In the case of the illustrated embodiment, the thickness T ₁₈ of the thrust minute gap _{18 is changed} to the radial minute gap 16.
Are small (T ₁₈ <T ₁₆₎ than the thickness T ₁₆ of the.
The upper surface of the sleeve 14a is formed as a mortar-shaped inclined surface 19 that becomes lower toward the inside in the diameter direction. Furthermore,
A step 20 is formed at the lower end of the sleeve 14a over the entire circumference, and a pair of corners 2
1, 21 are provided. And each of these corners 21, 2
1 is in sliding contact with the outer peripheral surface of a curved portion 22 formed at the base end of the second cylindrical portion 15. In the case of the bearing device of the present invention configured as described above, the upper end of the radial minute gap 16 is
7, rainwater or the like splashed from above does not directly enter the radial minute gap 16. At the upper end of the radial minute gap 16, a thrust minute gap 1 is provided.
Although one end of 8 is continuous, the other end of the minute thrust gap 18 is opened inward in the diameter direction, so that the rainwater or the like hardly enters the minute thrust gap 18. As a result, it becomes difficult for this rainwater or the like to enter the rolling element 4 installation portion. In particular, in the case of the illustrated embodiment, since the thickness T18 of the thrust minute gap ₁₈ is small, the thrust minute gap 18 functions as a labyrinth seal,
This effectively prevents rainwater or the like from entering the radial minute gap 16. Further, the upper surface of the sleeve 14a is
Therefore, rainwater or the like flowing down on the upper surface is efficiently discharged to the inside of the second cylindrical portion 15. Accordingly, it is possible to effectively prevent the rainwater or the like from entering between the upper surface of the inner race 2 and the lower surface of the upper support and the like, and from entering between the inner bent portion 7 and the outer bent portion 9 into the portion where the rolling element 4 is installed. Note that the upper end edge of the second cylindrical portion 15 may be formed as a mortar-shaped inclined surface, and the lower surface of the protruding portion 17 may be inclined in the same direction. Each surface is inclined in this manner, and the thrust minute gap 1 is formed.
By inclining 8 in a downward direction as it goes inward in the diametrical direction, the effect of preventing rainwater or the like from entering can be further ensured. Furthermore, even if rainwater or the like enters the radial minute gap 16 through the thrust minute gap 18, in the illustrated embodiment, the lower end of the sleeve 14a and the upper spring seat 1 are in sliding contact with each other. Therefore, the rainwater does not reach the rolling element 4 installation portion. That is, in the case of the present embodiment, the pair of corner portions 21 and 21 provided on the sleeve 14a side and the curved portion 22 formed on the upper spring seat 1 side are in sliding contact with each other. Function as contact seals, respectively, to prevent entry of rainwater or the like. or,
Even if a slight gap is formed between the pair of sliding contact portions, the pair of corner portions 21 and 21 functions as a labyrinth seal, so that the above-described prevention of entry is reliably achieved. FIG. 3 shows a second embodiment of the present invention. In the above-described first embodiment, the entire upper surface of the sleeve 14a is formed as a mortar-shaped inclined surface 19. In the case of this embodiment, only the upper surface of the protrusion 17a is formed as a mortar-shaped inclined surface. 19a. The upper surface of the main body of the sleeve 14b is a flat surface. In the case of the present embodiment, since the inclination angle of the inclined surface 19a can be increased (steep), foreign matters such as mud contained in rainwater or the like can hardly collect near the opening of the thrust minute gap 18. The configuration and operation of the other parts are the same as those of the first embodiment described above, and therefore, the same reference numerals are given to the same parts, and redundant description will be omitted. FIG. 4 shows a third embodiment of the present invention. In the case of the present embodiment, a hanging wall 23 is formed on the lower surface of the tip (right end in FIG. 4) of the protruding portion 17b.
A concave groove 24 that opens downward is formed between the outer peripheral surface of the sleeve 3 (left surface in FIG. 4) and the inner peripheral surface of the main body of the sleeve 14c. Then, the second cylindrical portion 15 is inserted into the concave groove 24. The upper surface of the sleeve 14c is a flat surface. In the case of the present embodiment, the second radial minute gap 25 is formed in a state where the upper end communicates with the inner diameter side end (the right end in FIG. 4) of the thrust minute gap 18. Moreover, the opening end of the second radial minute gap 25 faces downward. As a result, it is possible to more reliably prevent rainwater or the like from entering the radial minute gap 16. Since the configuration and operation of the other parts are the same as those of the first and second embodiments, the same reference numerals are given to the same parts, and the duplicate description will be omitted. FIG. 5 shows a fourth embodiment of the present invention. In the case of the present embodiment, a pair of steps 20, 20 are provided adjacent to the lower end of the sleeve 14d, so that the corners 21, 21 are provided at three places. And each corner 2
1 and 21 are slid on the outer peripheral surface of a curved portion 22 formed at the base end of the second cylindrical portion 15. In the case of the present embodiment, since there are three sliding contact portions, the sealing property between the lower end portion of the sleeve 14d and the curved portion 22 is improved. The configuration and operation of the other parts are the same as those of the first embodiment described above, and therefore, the same reference numerals are given to the same parts, and redundant description will be omitted. FIG. 6 shows a fifth embodiment of the present invention. In the case of the present embodiment, the apex angle of the pair of corners 21a, 21a formed so as to sandwich the step 20a is an obtuse angle,
The rigidity of each corner 21a, 21a is improved.
Since the configuration and operation of the other parts are the same as those of the first embodiment, the same reference numerals are given to the same parts, and the duplicate description will be omitted. Next, FIG. 7 shows a sixth embodiment of the present invention. In the case of the present embodiment, a curved surface 26 is formed at the lower end of the sleeve 14f, and the curved surface 26 and the curved portion 22 are brought into sliding contact with each other. In the case of the present embodiment, the sealing performance of the portion is ensured by increasing the sliding contact area. Since the configuration and operation of the other parts are the same as those of the first embodiment, the same reference numerals are given to the same parts, and the duplicate description will be omitted. FIG. 8 shows a seventh embodiment of the present invention. In the case of the present embodiment, the lower end of the sleeve 14g is extended to the lower side of the retainer 13 to form a curved surface 26a having a large area, and the curved surface 26a is brought into sliding contact with the curved portion 22. I have. In the case of the present embodiment, the sealability of this portion is ensured by making the sliding contact area larger than that of the sixth embodiment. The configuration and operation of the other parts are the same as those of the above-described sixth embodiment. Since the bearing device of the present invention is constructed and operates as described above, it is possible to reliably prevent foreign matters such as rainwater from entering the rolling element installation portion. As a result, it is possible to ensure the performance, durability and reliability of the bearing device.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a half sectional view showing a first embodiment of the present invention. FIG. 2 is an enlarged view of a portion A in FIG. FIG. 3 is a half sectional view showing the second embodiment. FIG. 4 is a half sectional view showing the third embodiment. FIG. 5 is a partial sectional view showing the fourth embodiment. FIG. 6 is a partial sectional view showing the fifth embodiment. FIG. 7 is a partial sectional view showing the sixth embodiment. FIG. 8 is a partial sectional view showing the seventh embodiment. FIG. 9 is a half sectional view showing one example of a conventional structure. DESCRIPTION OF SYMBOLS 1 Upper spring seat 2 Inner ring 3 Outer ring 4 Rolling element 5 Inner ring raceway 6 First cylindrical portion 7 Inner bent portion 8 Outer ring raceway 9 Outer bent portion 10 Core metal 11 Seal material 12 Seal ring 13 Cage 14, 14a, 14b, 14c, 14d, 14e, 14
f, 14g Sleeve 15 Second cylindrical portion 16 Radial minute gap 17, 17a, 17b Projection 18 Thrust minute gap 19, 19a Inclined surface 20, 20a Step 21, 21a Corner 22 Curved portion 23 Hanging wall 24 Groove 25 Second radial minute gap 26, 26a curved surface

──────────────────────────────────────────────────続 き Continued from the front page (56) References JP-A-55-159319 (JP, A) JP-A 58-97318 (JP, U) JP-A 62-134922 (JP, U) JP-A 59-159922 24530 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) F16C 17/00-27/08 F16C 33/00-43/08

Claims (1)

(57) [Claim 1] An annular first raceway ring having a first raceway on a lower surface and a first cylindrical portion protruding upward on an inner peripheral edge, respectively, and an upper surface. A ring-shaped second raceway having a second raceway, a plurality of rolling elements rotatably provided between the first raceway and the second raceway, and a cylindrical shape made of synthetic resin. And a sleeve fixed inside the first cylindrical portion, and the lower surface of the second race is brought into contact with the upper surface of a mating member constituting the suspension device. In a bearing device supported on the upper surface of the counterpart member, with the inner peripheral surface of the sleeve facing the outer peripheral surface of the formed second cylindrical portion with a radial minute gap therebetween, At the upper end of the inner peripheral surface, a projecting portion projecting inward in the diameter direction is formed over the entire circumference, and During assembly of the plane, the bearing device and the upper edge of the lower surface and the second cylindrical portion of the protruding portion and wherein the opposed through thrust small gap.